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ILLUSTRATED JOURNAL OF SCIENCE

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May 30, 1895 J

Nature

A WEKKI.Y

ILLUSTRATED JOURNAL OF SCIENCE

^^OLUME LI

NOVEMBER 1894 to APRIL 1895

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INDEX

AiMiAiiu-: (M. n'), Siilphiir-Kumig.itiim, a Remedy for Marsh

I'evers, 480
.\l)lie (I'ri)f. C. ), Insignificant SequeUe of Forest Fires, 158 ; the

l'(issil)iIitios of Long-Ranj^e Weather Forecasts, 212
Al'orileenshire Agricuhural Research Association, 614
Alicrv (Dr. ), the Transmission of Yellow Fever, 300
AhiK-'y (Capl. W. de W., C.B., F.R.S.), the Artificial Spectrum

'ro|). 292

AI'Murnuil Atlantic Was'es, C. E. Stromcyer, 437

Aliorigines of Australia, the. Dr. E. C. Stirling, 112

Al>s(ilutene.ss of Motions of Rotation, the Allege!, A. B.
Hasselt, F.R.S., 271 ; Prof. Oliver J. Lodge, F.R.S., 272

.\liuri ((lold Coast). Botanical Station, the, 423

.\cetvlene and (ixvgen, the Explosion of a .Mixture of, Dr.
T.'E. Thorpe, F.'R.S., 106

Achromatic Object-Glass, the New. 160

Ac nistics ; .Acoustic Fog .Signal and Navigation. A. B. Johnson,
130 : Application of Sound-Vibrations to .\nalysis of two
Ciases of different Densities, E. Hardy, 407 ; Objective Reality
of Omibination Tones, Prof. A. W. Riicker, and E. Euser,
550 ; Subjective Lowering of Pitch of Note, Dr. C. V.
Burton, 550 ; Objective Demonstration of Combination Tones,
Dr. C. \ . Burton, 550 ; a Simplified Phonograph, A. Koltzow,
5SS

.Acquired Characters: Right Hon. .Sir Edward Fry, F. R.S., 8,
197 ; Prof. E. Ray Lankester, F.R..S., 54, 102, 245 ; Edward B.
I'nulton. F.K.S.. 55, 126: Francis Oalton, F.R.S.,56: J. T.
Cunningham, 126. 293 ; John Clelanil, 294

Acton (E. Hamilton), I'r.actical Physiology of Plants, 577

.\dums (Prof.). Collected Memoirs, 254

Aeronautics: Lilicnthal's Experiments in Flying, 177; Maxim's
Experiments in Aerial Navigation, 259 : .Aeronautics in France,
Prof. Cornu, 299; Balloon Ascent by S. .Andrce, Prof. H, A.
llazen, 325; Andree's North Pole Balloon Scheme, W. 'de
Fonvielle, 421 ; the Andree Ballooning Expedition to the
North Pole, 513: Aerial Navigation, 436; Remarkable
Balloim .Ascent by Dr. A. Berson, 491

.l^Mlietic Tastes in Birds. 259

Africa : Death of Dr. Lent, 18 ; Death of Dr. Krelzschmar, l8 ;
the Anglo-tJerman Frontier .Survey in East Africa, C. S.
Smith, 19; Le Centre de I'Afriquc. Autour du Tchad, P.
lirunache, 29;- Dr. Donaldson Smith's Expedition to Lake
Rudolf, 61 ; British Central Africa Protectorate, H. H.
Johnstone. 66 : Forestry in Natal, Prof. \V. R. Fisher, 234 :
Return of Mr. G. F. S. Elliot, 29S ; How to live in Tropical
Africa, J. Murray, 364: the Death of Emin Pasha, R. D.
.Mohun,"38i ; the .Aburi Botanical Station, 423 : theCIlaciation
of Mount Ruwenzori, Scott Elliot, 441 ; Mr. Scott Elliot's
Explorations of Mount Ruwenzori, 527 ; Captain Manning's
Ascent of Mount Mlanje, 441 : Conspectus Flora> .Africx, ou
Enumeration des Plantes d'.Afri()Ue, Th. Durand et Hans
Schinz. 459 : Botanic dardens in South Africa, 491

Agamennone (Dr.), the .Alleged Diminution with Outward
Radiation of \'elocity of Earth()uake Waves, 299

.\<;e of the Earth, on the. Prof. John Perry, F.R.S., 224, 341.
'582 : Prof. Tait, 226; Lord Kelvin. P.R.S., 227, 438; Prof.
W. I. Sollas, F.R.S.. 553. 558; Dr. Bernard Hobson, 558;
Dr. Al.red R. W.illace, F.R.S., 607 : C. Davison, 607

.\griculture : a Dictionarv of llie Economic Products of India,
George Watt, 4; W. t. Thiselton-Dyer, F.R.S., 150; Dr.
\. Ball, F.R.S., 150: the Warble Fly, W. F. Kirby, 154;
Farm Vermin, Helpful and Harmful, 174; Oat-growing Ex-
periments, Prof. Kinch, 206 : Death and Obituary Notice of
Prof. Allen Harker, 206 ; .Advanced .Agriculture, H. J. Webb,
218; Canadian Experimental Farms, 237; the Roy.al Agri-

cultural Society, 252 : the .Anbur)- Turnij) Disease, Prof. W.
Somerville, 251; the "Finger and Toe " Discise, George
Massee, 453 ; Fox-tail Grass Pest in America, 301 ; Autumn
Cultivators for Green Manures, P. P. Dehcrain, 311 ; Agri-
cultural Art and Science, Prof. R. Waringlon, F. K.S.. 372;
Experiment with Dormant Seeds, Dr. .A. Pcier, 422 ; Horse
Breeding for Farmers, Alfred E. Pe.a>e, 435 : Injurious In-
.secis, Eleanor A. Ormerod, 471 : theCom|V>sition of Drainage
Waters, P. P. Deherain, 576 : the Department of Agriculture
in the Leeward Islands, 613; Field Ex[)crimenis in Wales,
614 ; Inquiry into Degeneration of R)e-grxss anil [wssible
Recovery, 614 ; Assimilable Nitrogen and ius Transfonnations
in -Arable Land, M. Pagnoul, 622

.Aikman (C. M.), Air. Water, and Disinfectants, 412

.Air, the Weight of a Litre of. Prof. Mendeleefl', 452

.Air and other Gases, Electrification of. Lord Kelvin, T'.R.S.,
Magnus Maclean, and Alexander Gait, 495

Air, Water, and Disinfectants, C. M. Aikman, 412

Alaskan Frontier Survey, the, Mounis Logan and St. Elias, ig

Alga;, Nitrogen Fixation in, Rmlolf Beer, 302

Algol, the System of, M. Tisserand, 328

-Algol Type, a New \'ariable Star of the. Dr. E. Hartwig, 64

Allen (H. N.), Energ)- Movements in Medium se|xtrating Elec-
trified or Gravitating Particles, 501

Almanac, the Nautical. 1S98, 472

Alpengllihen, das. Dr. J. Amsler, 346

Alpine Climates for Coiisum|ilion, H. J. llardwick, 54

Altona VVater-Supply, Bacteriological Investigation of the. Dr.
Reinsch, 231

Altschul (Dr.). Phosphore.scence at very Low Tem|x:ratures,
206 ; Behaviour of Brxlies at Critical Temi>erature, 431

-Amalitsky (Dr.), Com]iari5on of Russian and African (Karoo)
Permian Freshwater Shells, 599

Amber, Chinese Theories of the Origin of, Kumagusu Minakata,
294

.America : the -Alaskan Frontier Survey, Mount Logan and Mount
St. Elias, 19 : Journal of the Academy of Natural .Sciences of
Philadelphia, 26 : Travels among American Indians, their
Ancient Earthworks and Temples, \ice-.Admiral Lindesay
Brine, 26 ; American Meteorological Journal, 45, 142, 356,
451 ; -American Journal of Mathematics, 46. 406 : Bulletin of
American Mathematical Society, 46, 167, 261, 430. 525, 573 ;
a pre-Columbian Discovery of .America, \'ide Oldham, S3 ;
-American Journal of Science, 93, 190. 333, 430, 525, 619 ;
-American Museum of Natural Histor)-, 129 ; .American To|xi-
graphy. .A. Fowler, 274 ; the .-Vmerican .As.socialion, Dr. Wm.
H. Hale 390 ; Copper-sheathed Objects made by Alioriginal
Metallurgists of America, Profs. Putnam and M.ason, 490 ;
Entomolog)' in .Anterica, L. P. Howard. 490: American
Spiders and their .Spinning Work, Dr. Henry C. McCook,
Rev. O. P. Cambriilge, F.R.S., 505: .American Freshwater
Sponges in Ireland, Dr. R. Hanit.sch, 511 ; Public Libraries
in .America, 514

.Amphioxus, the Cranial Nerves of \'erlel)ralcs in, M. van
Wijhe, 120

.Amphioxus and the .\nceslry of the X'ertebrates, Arthur
Willey, 433

Amsler (Dr. J.), Das Alpengluhen, 346

.Amsterdam Royal .Academy of Sciences, 47, 119, 216, 407, 504,
623

Anatomy : Death of Dr. Francesco Gasco, 35 ; Journal of
.Anatomy and Physiology, 93 ; the Life of Sir Ricliar<l Owen,
169 ; the Cerebral Ciunniissures of the Mammalia, G. Elliott
Smith, 192 ; a Peculiarity in the Mammalian Tooth, Dr. John
Smith, 215 ; Lehrbuch tier \'ergleichenden .Anatomic, Arnold

VI

Index

tSuppUmcnt to Xatuir
May 30, 1895

Lang. Prof. K. Ray Lankcster. K.K.S.. 289: M.inual of

Traclical Morbid .\naloniy. H. D. Rollcsicn and -X. .\.

Kanthack, 31S : an Elemcntar)- Te.\t-Kx>k of .-Vnatomy, I'rof.

H. E. Clark, 412 ; Amphioxus and iht .\ncestr)' of the

Vertebrates, -Arthur VVilley, 433
Anderson (W. S. I. the .\lelho<l for Determining Density of Sea-

'.V.-,tcr. 61
.Anderson ( I'rof. ). Temperature of Maximum Density of Water

and its Coefficient of Expansion in neighliourhood of this

Temperature, 358
.Andre (Desire), Sequences of Circular Permutations, 576
.Vn.lrc ((i.l, .Alumina in Plants, 407; Principles in Plants

(".q^dilc of Condensation with Production of Cirlxjnic .Acid, 46
.Arilrte (S. A.), Rilloon .Ascent by. Prof. H. .A. Haxen, 325
Andrcc's North Pole Balloon-Scheme, 513 ; W, de Fonvielle,

421
-Andrewes and Lawes (Messrs.), the Harmlessness of Sewer .Air,

37'

.Anilrews (Th(>s. ), Death and Obituary Notice of, 279

.Andrews (T. I, Influence of Stress in Corrosion of Metals, 470

.\ncninnieier. Electrical, Mo<lifications of an, Rev. .M.arc
I )echcvrens, 326

-Ancmometry and Vertical Current of At.iiosphcre, M. Kitter,
469

.Angot (.Alfred). Les .Aurores Polaires, 484

.Aniline. Sjiecific Heat of, E. H. Criffiths. 71

.Animals and Plants, \'arialion in. Prof. W. K. R. Weldon,
K.R.S., 449

.Animation, the Sus|x;nded, of Snakes, S. Garman, 274 ; W.
Kenne<ly, 274

.\nnals of British Ccolog)-, 1893, J. K. Blake, 557

.Anthropology : the .Almrigines of .Australia, Dr. E. C. Stirling,
112: Prehistoric Ceramics from Langenlclmrn Tumulus, J.
Szomtathy, 157 : Prehistoric Objects in N.E. Italian
Museums, Dr. Iloernes, 157: Woman's Share in Primitive
Culture, O. T. M.ason, 244 ; the .Samoy.ad Race, .Arthur
Montefiorc. 279; Pithecanthropus Ercctus, einc Mcnschenaehn-
lichc l'eliergangsfi>rniaus lava, E. Dubois, 291 ; Dr. Duljois' so-
called Missing Link, 428 ; Dubois on Pithecanthropoid Remains
found in Java, .Sir W. Turner, 621 ; Giants and Giantism, Dr.
C. L. Dana, 38 1 ; the New Eire Ceremony among the
Tusayan Indians, [. W. Eewkcs, 515 ; the Varieties of the
Human Species, Prof. (Jiuscppc Sergi, 595; Lake-dwelling
Research, Dr. Munro, 621

Anthro|x>mctry : the Growth of St. Louis Children, William
Townscnd IV>rter, Prof. Karl Pearson, 145

.Antilles, the Snail Eauna of the Greater, 524

Aniifinily of the Einger-I'rint .Method, the, Kumagiisu
Kata, 199

1' Serum Treatment of Diphtheria, the, Dr. (i. .Sims
Ihead, 402, 425

.Ants, Para-sol. Origin of Cla-sses among the, I lerhert -Spencer, 125

.\|)ostoli (M. ), Therapenlic .action of Currents of High
Frctjuency, 528

Aprontions and Thought Transference, Frank Podmore, II. G.
Wells. 121

.Aralrs. Cows kc|)t in Caves by. Colonel A. T. Eraser, 325

.\r.ichnid.'.' : Development of Lungs of Spiders, O. L. .Sim-
mons, 37 ; Malaysian Spiders, Thomas anil M. E. Workman,
R. I. Pocock, 99; L'hwluslrie des Araneina, Woldemar
Wagner. 363 ; Siune .Suggestions on the Origin and Evolu-
tion of Web-Spinning in .Spiders, R. I. Pocock, 417 : the
Presence of a Siridulating (Jrgan in a .Spider, Prof. Baldwin
Spencer, 438 ; .American .Spiders and their .Spinning-Work,
Dr. Henry- C. McCV^.k, Rev. O. P. Cambridge, E.R.S., 505

.Araneina, L'Industrie des, Waldemar W.agner. 363

AnhroNigy : Travels among American Indians, their Ancient
I .irthworks and Temples, Vice- Admiral Limlesay Brine, 26 ;
I'.iih of Sir Charles T. Newton, 129; Copper-sheathed
Objects made by Ab<iriginal Metallurgists of America, Profs.
Mav.n and Putnam, 490: De|Hisii of River-Alluvium a.s
''• " ■ ' r Measuring Antiipiity of River-Mounds, Dr.

-N . ! : Bilge- Keels anil Steadiness in Battle-Shi|xs,

Sir Wilham While, 568; R. E. Eniudc, 569 ; \'ibralion of
Sfc^mir-.. Olio -Schlick, 569: W- Mallock, 570; .Mark
1 ' yx. \\. R. Sankey, 570

A '•■ Variations in Level of Wcll-Water, 62

Return of .Mr. .A. Trevor- Battye, 10 : Mr.

isit III Kolguef Island, ;0 ; l<e|»iirteil Wreck

11; ISarun Toll'.s -Sil)cri.in Ex|H.dition, 327 ;

-Andrce's Balloon Scheme, 513 : W- de Fonvielle, 421 ;
Cruise of the Xaycuinik^ N- Knipovitch, 500

Arclowsky (Henryk), Double Decompositions of \"apours, 477
-•Vtion of Heat on Carbon Bisulphide, 620

-Argentine, Earthquake in the, 18

-Argentine Eartlu|uake Pulsations of Octolier 27, the Velocity ot
the, C. Davison, 462

.■\rgentine. Meteorology- in the. 253

-Argon, 323, 337: m! Bcrlhelui. 3S4. 527, 622: Di. 1. H.
Gladstone, E. R.S., 3S9 : Prof. Mcndeleeff, 543 ; " .Argon " the
New Constilutent of the -Atmosphere, Lord Kayleigh, Sec.
R.S. , and Prof. William Ramsay, E. U.S., 347 ; on the .Spectra
of, William Crookes. K. K.S., 354; 11. E. Newall, 454;
Fluorescence Spectrum of, .M. Berthelot, 622 ; the Lii|uefaction
and Solidification of .Argon. Dr. K. Olszewski, 355 : Do Plants
a-ssimil.ate .-Vrgon ? E. Blass. 461 : Prof. W. Ramsay. E. R..S.,
461 : .Argon and the Pcriinlic System, Prof. ]. l-^merson
Reynolds, E. R.S. , 486; .-^rgon in Nebul.v, Dr. B. Brauncr,
513 : .Attempts to Produce Chemical Combinations with .Argon,
^l. Berthelot, 527 : Simple Demonstration of Presence of
.Argcui in .Atmospheric Nitrogen, .M. Guntz, 599 ; .Argoit not
in \'egetable or .-Vnimal Substances, G. W'. MacDonald, ami
A. .M. Kellas, 620

.Vrithnielicians, Ment.al, Psychology of, and Blindfold Chess-
Players, .Alfred Bind, Francis Galton, F.R.S., 73

Armstrong (Dr. H. E., E.R.S.), Research in Education, 463 ;
.Address at the .Anniversary Meeting of the Chemical .Society,

535

.\rmstrong (Col. R. V., F.R.S.), Death of, 61

-Art, the Origins of. Dr. E. Grossc, Prof. \. C. Haddon, 241

Artificial SjDectrum Top, the, Chas. E. Benham, 200 ; Prof. G.
D. Liveing, F.R.S., 200 ; Newton and Co., 463

.Aschkinass (Dr. IC), Refraction and Dispersion of Rays of
Electric Force. 70 ; Influence of Electric Waves on Galvanic
Resistance of .Metallic Conductors. 288

.Ashworih (I. Reginald), Electroscopes in Lecture, 343

.Asia, Central, French Scientific Expedition to, 421

v\sialic .Society of Bengal, Journal of, 500

.Assuan, the Nile Reservoir at, 110

.Vsteroids, a po.s.sible New Zone of, Prof. Newcor.ih, 1 14; an
Import.ant -Asteroid, .M. Tisseiand, 254 ; the Mass of the
.Asteroids, M. Roszel, 373

.Astro-Physical Journal, the, 234

.Astronomy: Our .Vstronomical Column, 21, 40, 64, S5, 114,
132, 160. 1S3, 207, 233, 253. 2S2. 301. 327. 347. 373, 395,
425, 443, 471, 493. 516, 542, 564, 589, 616 : the .Spectrum of
S Cephei, Dr. Belopolsky, 21, 282; the Rotation of \enus,
M. Flammarion, 21 ; the Lowe Observatory, 21 ; the .Mean
Parallax of .Stars, Prof. Hugo Gyldcn, 21 ; Astronomical
Theory of Ice .Age, E. P. Culverwell, },}„ 371 : Presentation
to llerve l'"aye, 36: Two Variable Slars, Rev. T. l-'.. Espin,
40: a New Varialile .Star of the .\lgol Type, Dr. E. llarlwig,
64; a New .Short Perird Variable. .Mr. N'endell, 233; the
Variable .Star f llerculis, 616 ; Radial Velocity of, II. Des-
landres, 263 ; the \ariable Star fl (.Algol) in Perseus, F. Tis-
.serand, 336 : Irregularities in Variable .Stars, W. Maxwell
Reed, 183 ; a Comet on the Eclipse Photographs of 1893, 40
Mira Ceti, .Mr. Fowler, 40; Observations iif Mars, 40 ; the
Polar Caps of Mars, 64 ; Schiaparelli on .Mars, Prof.
W. II. Pickering, 87; the Speclrum of Mars, I'rof. W.
W. Campb.;ll, 132 ; .Seasonal Clianges on .Mars, Percival
Lowell, 259: Mars in 1894, Signor (!. Schiaparelli, 395; the
Satellites of Mars, Prof. Campbell, 443; Encke's Comet,
Prof. .\1. Wolf, 64, Return of, 40: Ephemeris of. Dr. ( ).
Backlund, 85: History of, W. T. Lynn, 108; the Transit of
Mercury, 40, 85, ifio, 253 ; the .AppareiU Diameters of .Mer-
cury, Prof. Barnard, 373 ; ihe Possibility of Life in other
Worlds, Sir Robert Ball, F. R.S..44; .Astronomia Sferica,
Francesco Porm, 53; Wilhelm Olbers, sein Leben uml
seine Werke, 74 : Recent Observations of Jupiter. Prof. E. E.
Barnard, 85 ; Jupiter, W. F. Denning. 227; Pseudo-Satellites
of Jupiter in the Seventeenth Century, Charles W. L. Johnson,
285 : a Passige of Shadows of Jupiter's Fourth Satellite, J.J.
I^anderer, 384 ; Death of Dr. I- Schwar/, III : the Parallax
of Nebula /; 2241, Dr. Wilsing, 114 ; a Possible New /one of
Asteroids, Prof. Newcomb, 114; a New Comet, l"-dwaril
Swift, 114, 132; I'.phemeris for Swift '.s Comet, I(jo; Cimiet
e 1894 (.Swift), 542 : Pholographii: Studies of Lunar .Surface,
MM. Lirwyand I'uiseux, 143: Motion and Magnitude. Prof.
Oudemniis, 160; a New .Achromatic Object-t ilass, 160: a
New Star, Rev. T. E. l-^spin, 161 ; Radiant Suns, .\gnes

Siijtjftemcnl to Xature~\
May 30, 1895 J

Index

VII

Gibsrne, 174 ; Obituary Notice of Dr. C. F. W. Peters,
Father F. Denza, and A. C. Kanyard, 179 ; Secular
Variations of the Interior I'lanets, Prof. Newcomb,
183 : the Radcliffe Catalogue, 183 ; L' Astronomic, 183 ;
the Lick Obsenator)', A. Fowler, 20I ; .Vlvances in Lunar
I'hotogra]ihy. MM. L<ewy and Puiseux, 207 ; Cometary
Ephemerides, 207 : Russian .-Vstronomical Observations, 207 ;
the (Ireater Nebula of Orion, I'rof. F. E. Barnard, 253 ;
Spectrum of the Orion Nebula, 471 ; the Orion Nebula, Prcjf.
W. H. Pickering, 564: an Imjjortant .•Vsteroid, M. Tisserand,
254 ; Collected Memoirs of Prof. .-Xdams, 254 ; Dopplcr's Prin-
ciple, Dr. Belopolsky. 233 ; the .^stro- Physical Journal, 234;
Elliptical Orbits. Mr. 1!. Larkin, 234 : Elements of.Vstrononiy,
Ci. W. Parker. 270 ; Intercolonial .Vsironomy and Meteorology,
27S; the Vatican Observatory, 282 ; an Indispensable .\nnuaire,
282 ; the Unification of Civil and .Vstronomical Days, 282 ;
the Planet Earth, an .Astronomical Introduction to (Jeography,
R. A. Oregory, 291 : the Perseid Meteors, Dr. Bredichin,
301 ; VV. F. Denning, 320 ; Stars having Peculiar Spectra,
Prof. E. C. Pickering, 302 ; Comet 1894 I. (Denning) and
Brorsen's Comet, Dr. Hind, 302 ; Dr. E. Lamp. 302 : the
Identity of Denning's and Brorsen's Comets. 425 : the Natal
Observatory. Mr. Nenll, 327 ; the New Dudley Observatorj-,
327 ; the Milky Way, C. Easton, 327 ; the System of .Vlgol,
M. Tisserand, 328 ; Recent Work at Harvard College
Observatory, Prof. E. C. Pickering, 329 ; New Stars and
Nebula-, 347 ; the Designation of Comets, 347 . the
Mass of the .\steroids, B. .M. Ros/.el, 373 ; the Variation
of Latitude, 373 ; the Sun's Place in Nature, J. Norman
Lockyer, C.B., F.R.S., 374, 396, 565, "590; the

■ Zodiacal Light, Rear-.Vdmiral J. P. .Maclear, 391 ; Novel
Methods in Photometry, Dr. Janssen, 395 ; .Atmospheric
Dispersion, Dr. Rambaut, 396: Hesper and Phos|>hor,
Kumagusu Minakata, 417 ; Origin of the Lunar Formations,
.M. Stanislas Meunier, 425 : 7 Ca.ssiopeia;, 425 ; the Story
of the Stars, George V . Chambers, 436 ; Spectroscopic
Measures of Planetary Velocities, .M. Deslandres, 443 ;
Eclipse of the Moon, 444 : the Eclipse of the Moon, 472 ;
the Nautical Almanac, 1898, 472; Observations on .Sun-Spot
Spectra, J. Norman Lockyer, F. R..S., 448; Photographic

■ Measurement of Time, (_;. Lippmann, 455 : Determination of
Position of Pole by Photography. C. Flammarion, 455 ; a
Few Chapters in .Astronomy, Claudius Kennedy, 484 : Partial
Eclipse of the .Sun, March 26, 493 : Distribution of .Minor
Planets. General Parmentier, 493 ; ihe Royal Observatory,
Eilinburgh, 493; Stoney's Local Heliostal and Improved
Siderostat, 500; .Astrononiische Chronologic, Walter P". Wisli-
cenus, 509 : Argon in Nebula?, Dr. B. Brauner, 513 : the .Moon
and .Atmospheric Waves, Bouquet delaGrye, 516; Stellar Photo-
graphy, 516 : Standard Time in Australia. 516 ; Nova Aurig;v,
516; a Possible New Satellite of Neptune, Prof. .Schaeberle,
542 ; the Diameter of Neptune, Prof. Barnard, 617 ; Improve-
ments in Photometry, 55S ; Death of Theodor Brorsen, 561 ;
the Lyrid Meteors, 564 ; a New Fc)rni of Zenith Telescope,
Louis Fabry, 564 ; Lunar River Beds and Variable .Spots,
Prof. W. II. Pickering, 589 ; the Ultra-Violet Spectrum of
the Corona, 589 : M. Deslandre.s' Stellar Parallaxes, T. Lewis,
589; .Astronomical Coordinates referred to .Astronomical and
( leograjihical Poles, respectively compared, Ch. Lagrange,
620

.Atkinson (Rev. J. C. ), Memorials of Old Whitby, 149
.Atlantic Waves, Abnormal, C. E. Stromeyer, 437
Atmosphere, the New Constituent of the. Lord Rayleigh,'Sec.

R.S.. and Prof. William Ramsay, F. R..S., 347
Atmospheric Dispersion, Dr. Rambaut, 396
Atmospheric Waves, the Moon and, M. Bouquet de la Grye,

516
Atoll, Studies of a (Growing, Dr. Hugh RoI>crt Mill, 203
Attitudes. Instinctive, S. S. Buckman, 31
Aubertin (f. L). "By Order of the Sun to Chile to see his

Total Eclipse, .April 16, 1893," '°'
Auk, Great, Sale of Specimen of, 613
Auk. the Little, Invasion of North and North-East Coasts by,

I. E. Ilarling, 422
Aiiror.e : .Aurora of November 23, ]. Shaw, 107 ; Prof. A. S.

Iler.schel. F.R.S., 246, 390; W. II. Wood, 390; Les

.Aurores Polaires, .Alfreil .Angot, 484: .Aurora of March 13,

517; the Recent .Auroral Phenomena, James G. Richmond,

581
.Australia, the Aborigines of. Dr. E. C. Stirling, 112; the

Province of South .Australia, J. D. Woods, 221 ; the Horn

Expedition lo Central .\ustralia. Prof, liddwin S|)encer, 222

Meteorological Work in .Australia, Sir C. Todd, F.R.S., 306 ;

.Standard Time in, 516
Austria- Hungary-, Earthquake in, 587
Aventurine (Jlass, H. S. Washington, 112
Avogadro's Rule, and Thermodynamics, Theoretical Chemistr.-

from the Stand|X)int of, Prof.'Walter Nemst, .M. M. Pattiwm

Muir, 530
.Ayrton (Prof.), Student's .Apjjaratus for verifying Ohm's Law,

142 ; Student's Apparatus for determining .Mechanical

Equivalent of Heat, 239 ; Tests of Glow Lamps, 239, 358

Bach (.A. ), New Reagent allowing Demonstration of Presence of
Hydrogen in Green Plants, 240

Bacillus (C/avi/ormis), a. New Anthrax, .A. Chaveau and C.
Phisalix, 622

Backlund (Dr. O.), F:phemeris o) Encke's Comet, 85

Bacteriolog)- : the Treatment of Diphtheria by .Anti-Toxic
Serum, Dr. M. .A. Ruffer, 16 ; Dr. G. S. Woodhead, 402, 425 ;
Relative Efficiency of Water-Filters, Surgeon-.Major Johnston
38 : Reduction of Sulphates by Specific Sulphi<ic Ferment.
.M. Beyerinck. 47 : .Action of High Pressures on Bacteria. H.
Roger, 168 : the Di.sinfeclion of Frecal .Matter by Copjxir Sul-
ph.ate, H. Vincent, 168: Bacteriological Institute to Ix; estab-
lished at Kielif University, 206; Investigation of the .Altrna
Water Supply, Dr. Reinsc'h, 231 ; Death of Dr. Josef Schroter,
251; .Nitrogen Fixation in .Alg;i;, Rudolf Beer, 302; the
I larmlessness of Sewer .\ir, .Messrs. Laws and Andrewes,
371 : Oysters and Typhoid, 391 : Mrs. Percy Frankland,4i5 ;
I^'hrlmch der Bakteriologischen Unlersuchung und Diag-
nostik. Dr. Ludwig Heim, .Mrs. Percy Frankland, 481 : Con-
ditions afiecting Bacterial Life in Thames Water, Dr. E.
Frankland, F.R.S., 599 : a New .Anthrax Bacillus 1 (:.■;. -
foniiis), A. Chauveau and C. Phisalix, 622

Baker (J. L.) .Action of Diastase on Starch, 359

Baker (R. T. ), New Isopogon from New Soutih Walc>, 192

Balances, Improvements in Sensitive, W. H. P. Kuhhnann ami
Dr. Classen, 540

Ball (Sir Robert, F.R.S.), the Possibility of Life in other
Worlds, 44

Ball (Dr. V.. F.R.S.), Dr. Watts' Dictionary of the Economic
Products of India, 150

Ball(5.)n .Ascent by Dr. .A. Borsen, Remarkable, 491

Ballore(M. de .Montessus de), the Frequency of Earthquakes,
540

Baly (E. C. C), Possible Explanation of Two-fold Spectra of
Oxygen and Nitrogen, 550

Baratta (Dr. M. ), the Sicilian Earthquakes of August 1S94, 207 ;
.Seismic Historj- of Calnhria iilira, 468

Barber (Rev. Samuel), a White Rainbow, 274

Baring-Gould (S. ), the Deserts of Southern France: an Intro-
duction to the Limestone and Chalk Plateaux of Ancient
.Aquitaine, Canon Bonney, F. R..S.. ico

Barlow (Wm.). Homogeneity of Structure the Source of Crystal
Symmetr)", 58

Barnar<l ( Prol. E. E. ), Recent Olwervations of Jupiter, 85 ; the
Greater Nebula of Orion, 253 ; the .Apiarent Diameters of
Mercury, 373 ; the Diameter of Neptune, 617

Barometer, the Invention i>f the. Prof. G. Hellm.ann. 422

Barrenness of Pre-Cambrian Rocks, the. Dr. C. C^illaway. 462

Bartoli (Prof. .A. I, Determinations of .Absorption of SoLir
Radiation by Fog and Cirrus Cloud, 180; Solar Heat in-
terrupted by Volcanic Dust, 279

Barus (Carl), a Simple Chronograph Pendulum, 84 ;. Colloidal
.Silver, 190

Bashforth (Rev. F. ), the Measurement of Presisures in Guns, 461

B.a.ssel (A. B., F.R.S.), Discontinuous .Motion, II; the
.Alleged .Absoluteness of .Motions of Rotation, 271

Bateson (W., F.R.S.), the Origin of the Cultirated Cineraria,
605

Bateson's Theor)' of Organic Evolution, Reason of Failure of,
Dr. A. R. Wallace, 450

Ballanilicr (M.), Reactions of Chelidonine with Phenols in
.Suljihuric Solution, 384

Rtttleof the Forests, the. Prof. R E. Femow, I16, 139

Baubigny (H.), .Antimony \'ermilion not .an Oxy.sulphide, 24

Bauer (L. A.), Wilde's Theory of the Secular Variation 1
Terrestrial M.tgnetism, J03 : some Early Terrestrial .Magneiir
Discoveries pertaining to England, Will Whiston, 295 : .Secular
Changes of Terrestrial .Magnetism, 431 ; the .Secular N'ariatii n
of Terrestrial M.agnetism, 491

VIll

Index

CSHpfUment to Xaittrr,
May 30, 1895

Baunihauer (Dr. H.), Die Kesultate iler Aetzmethcnle in der

knslallc^raphischcn Forichung, an einer Reihe von krjstal-

lisirten Kiir|iem ilargestcllt, 340
Ba)'ard (F. C. ). <hc Prost of januan- and February 1895, ^-'
Baj-ard's (H.) I'hologniphic Researches, \V. H. Harrison, 299
Bayer (Dr.), New Element in the Nitrogen Uroup discovered by,

258
Beauty, Feeling of, in Birds, 259

Beazley (C. Raymond), Prince Henry the Navigator, 532
Beddard (F. E., F. R.S. ), the Visceral Anatomy of Ornitho-

rhjTichus, 191
Beecher (C. F. ). Trinucleus. 619
Beer (Rudolf), Nitrogen Fixation in Algx, 302
Bees in December, a Swanii of, 230
Beetham U\- W., F.R.S.), Death of, 4SS
Belgique, Bulletin de 1' Academic Roj-alc de. 46, 16". 477. 620
Bell (James), the Telegraphist"* t'luide, 4S4
Belopolsky (M. A.), the Sjiectrum of S Cephei, 21, 2S2 :

Doppler's Principle, 233
Bendix (Dr.), Influence of Sterilisation on Digestibility of

.Milk. 96
Bengal, Journal of Asiatic Society of, 500
Bcnham (C. E.), an Artilicial Spectrum Top, 113, 200. 321 :

Prof. Livcing, 167
Bennett (Alfred \V.), the Planting of Timber Trees, ^^
Bentley (\V. H.), Methylisolmtylacetic Acid, 526
Berkeley ( Earl of). Accurate Method of determining Densities

of Solids, 431
Berlin .Meteorological Society, 72, 192, 431, 503, 623
Berlin Physical Society, 96, 168, 191, 28S, 431. 503. 623
Berlin Physiological Society, 96, 192, 216, 288, 312, 431. 503,

Ber in and Vcnna, Telephone Communication opened between,
129 >

Berlioz (M.), Therapeutic Action of Currents of High Fre-
c|uency, 528

Bernard (H. M.), (he Spinning Clland in F'hrynus, 263; Com
parative Morphology of GaUoduhc, 455

Berlhelot (.M.): Principles in Plants capable of Condensation
with PrcKluctionof Carlxjnic .Vcid, 46; .•\rgon,384; Attempts
to produce Chemical Combinations with Argon. 527 : the
Spectra of Argon and of the .-Xurora Borealis, 552 : Alumina
in I'lanLs, 407 ; Fluorescence Sixictnim of Argon, 622 ;
Banquet to, 586

Berlhelot (D. ), New Mctho<l of Temperature-me.'isurcment, 622

Bcrtrand (G.), Pecla.se ami Pectic Fermentation, 191, 312

Be-i^on (A.), Carbonyl Chloro- Bromide and Dibromide, 359

Bcyerinck (.M.), Reduction of Sulphates by Specific Sulphide
Ferment, 47

Bezold (Prof, von): Increase of Damage by Lightning, 20;
Unstable Equilibrium of Atmosphere before Thunderstorms, ,
503

Bhang Plants, the. Dr. Train, 143

Bidstrm, .Slonn Statistics at. William E. I'lummcr, 272

Bieilemiann (Prof. W. ), Electrophysiologic, Prof. J. Burdon j
Sanderson, F.R.S., 553

Bigelow (F. H.): Inversion of Temperatures in 26-68 Day •
.Solar M.ignelic Period, 190 ; Solar Magnetism in Meteoro-
. log) • 356

Binet (.\lfrcd). Psychologic dcs Grands Calculateurs et Joueurs
d'Echecs, Francis Galton, F.R.S., 73

Biology : Neo-\'ilalism, Frances A. Welby, 43 : the Present
State of Physiological Research, 5S ; Hct)ucst by Prof.
Pouchct to Paris .Society, 61 ; Biolog\- in the United Slates,
A. PrtjsiK-rt. 81 : Outlines of Biolog),' P. Chalmeiti Mitchell,
H. (J. Wells, 195 ; Biological Leclures and .\dilresses de-
livered by the lafe Arthur Milnes Marshall, F. R.S., 217 ;'
Zeit uml Streilfragen iler Hitilogie, Prof. Dr. Oscar llertwig.
G. C. Bourne. 265: the Plon Station. 278: Biological Station
to lie established on a North Indiana U-tkc, 422 ; Influence
of Temperature on Disirilnition of Animals and Plants. Dr. C.
M. .Mcrriam, 441 ; Bi.il.^ir.nl Work on the Illinois River.
593 : Marine Biology. ;i Flying Co)h;|)<xI. Dr. OstnnimofT. 20 ;
FKini- (. ■..!:.. k r ...lin llendorft', 300: the Solowelzk
S I'hysical Invcsligatinns in Faroe-

Si ■ - i ' , 1 11 of Compression on Segmentation

of .Sci-L r. liii, l-,gg, Di. .\. Graf. 157; Julina. New Ant-
arctic Coni|Hmnd Ascidian, W. T. Caiman, 213; Merma-
p' ' ' ■■ Dr. Paul Pelsencer. 213; the

'' ; Medu5,T. Ida II. Hyde. 231 ; Die \

1-^ - - '<■ -i- ■ i-,;liiere, Prof. Johannes Walther, 269; ,

the Port Erin Station, Prof. Ilerdman, 2S1 : Effect on
Environment on Development of Echinoderm Larv.t. H. M.
N'emon. 454 ; Com|xirati\e Mor|)holog)' of GaUodidtt^ H.
M. Bernard, 455 ; Role of Am;vl>ocytes in- Annelids, E. G.
Racovit/j. 455 : the Brooklyn Summer School, 537
Bird-Winged Hutterflies of the East, the, W. F. Kirby, 254 ;

Robert H. F. Ripiwn, 343
Birds, the Crommelin Collection of Dutch, iS : the Nests and
Eggs of Ni>n-indigenous British Birds, Charles Dixon, 30 ;
the Wind and the Flight of Birds, Profs. Langlcy and Curtis,
156 : Birds of the Wave and Woodland, Phil Robinson, 243;
the Tongue and Hyoid .Vpixiratus of Birds, Herr Schenkling-
Prevot, 252 ; Feeling of Beauty in. 259: British Birds, Claude
W. Wyatte, 318 : Summer Studies of Birds and Books, W.
W.irde Fowler, 341 : Forest Birds, their Haunts and Habits,
Harry K. Wilherby, 341 ; the Birils of Eastern Pennsylvania
and New Jersey, 45S : Bird Notes, Jane Mary Hayw.,
532 ; Catalogue of the Birds of Prey (.Accipitres and Strit;!
J. H. Gurney, 532
Birmingham. ,Str;issburg, and Nicolaiew, on a Remarkable Earth-
quake Disturbance observed on June 3, 1893, ^- Davison, Dr.
E. von Rcheur Paschwil/., 203
Bischoff (Dr. C. \.), Handbuch der .Stereochemie, 409
Bjerknes (W). Different Forms of Multiple Resonance, 357
Black-Damp, Dr. John Haldane, 477

Black-\'cined White Butterfly, the, W. Warde Fowler, 367
Blackman (F. F.), New .Methoil for investigating Carbonic
Acid Exchanges of Plants, 238 ; Paths of Ciaseous Exchange
between .\erial Leaves and Atmosphere. 23S
Blake (J. F. ), .Xnnals of British Geologv, 1S93, 557
Blanford (Dr. W. T., F.R.S.), the Burmese Chipped Flints,

Pliocene not Miocene, 608
Blass (E.), Do Plants assimilate .Vrgon ? 461
Blindfold Chess- Players. Psychology of .Mental .Arithmeticians

and, Alfred Binet, Francis Galton, F. R.S., 73
Blue Grotto of Capri Spectroscopically Tested, Dr. H. W.

\'ogel. 300
Blythe (W. H.), Model of the 27 lines on a Cubic Surface, 95
Bock (.-v.). Ratio bel«een Lateral Contriction and Longitudinal

Dilatation in Magnetised Iron Rods. 614
Boernstein ( Prof. ). Influence of Pol.aris,ation on Outflow of Nega-
tive Electricity cau.sed by Light. 96
Boiler Explosions, W. H. Fowler, 345
Boiler Explosions, Kitchen, R. D. Munro, 197
Boiler Shells. Drilling Machines for. .Samuel Dixon, 22
Boislaudran (Lecoq de). .Uimiic Weights. 432
Boltzmann (Prof.) and the Kinetic Theory of iLiscs. 413, 581,
G. H. Bryan. 31 ; Edward P. Culverwell. 581 ; Boltzmann's
Minimum Function, S. H. Burbury. I''.R.,S.. 78, 320; Boltj-
mann's Mininunn Theorem, Rev, 11. W. Watson, F.R.S.,
105 : Edward P. Culverwell, 105, 246
Bone (W. .\. ). Incomplete Combustion of some Gaseous Carbon

Com]K)unds, 143
Bonney (Canon, F. R.S.), the Deserts of .Southern France, an
Introduction to the Limestone and Chalk Plateaux of .-Xncicnt
Aquitaine, S. Baring-Gould, 100: Lcs Abimes, les eaux
souterraines, les Cavernes, lcs Sources, la Si^'la-ologie,
E. A. Martel, 410
Borchers(Dr. W.), the Relation of Energy of Combination to

Electrical Energy, 141
Bordas(F.), Chemical Process for Purification of Water, 552
Botany ; Death of Dr. Lent, iS ; Nuovo IJiornale Botajiico
Italiano, 23 ; the Mechanism of Vegetable Respiration, L.
M.iquenne, 24; Death of Prof. M. Ducharlre, 35; .Sawer's
Rhodologia, 39 ; Principles in Plants capable of Condensation
with Production of CarlHinic .\cid, M. lierthelol and ( i. .Vndre,
46: Index Kewcnsis Planlarum Plianerogamaruni. .Sumptibus
Ueati Caroli Roberti Darwin ductu et consilio Joscphi D.
HiK>ker, confecil B. Daydon (.ackson. F.asciculus iii. 54;
Heliotropism. Dr. W. Rothert. 84 ; the New Cypress of
Ny.asaland. .85: the .Ascent of Sap. II. II. Dixon and Dr.
J. Joly, F.R.S.. 93: the .Soaking of Seeds. P. C. Glubb,
107 ; theCentrosphercs of Plant-Nuclei, Leon (iuignard, 113 ;
the Bhang Plant, Dr. Prain, 143: New Isopogon from New
South Wales, R. T. Baker, 192 ; New Souili Wales Linnean
Society, 192, 264; Additions to British Museum Herbarium,
206 ; a New Revision of the Diflfioiiir/vu-, .Sir D. Bramlis,
214; the Fertilisation of I.otiiulhiis kiaussianiis an<l
/.. dregti, Maurice .S. Evans, 235 ; New .Method for Investi-
gating Carbonic Acid Exchanges of Plants. V. Y. Blackman,
238 ; Paths of (.'■.aseous Exchange between Aerial Leaves

*< ii/>ptciitcKt to .\'aturc^~\
May 30, 189s J

Index

IX

ami Atmosphere, K. F. Blacknian, 238 ; Death of Dr. J. G. I
Hrinton, 251 : Monocotyledonous Saprophytes, I'crcy Groom,
J63 ; Kcmarkahle Oak Trees in Kssex, J. C. Shenslone, 280 ;
Death "f Dr. Kliickiger, 298 ; KoN-tail (Irass Test in .America,
301 ; Nitrogen Fixations in .^Iga-. Kiitlolf Hcer, 302 ; Deve-
lopment of Sieve-tubes in .•\ngiosperms, M. Chauveand, 336;
I.ehrliuch <ler Botanik, Drs. K. .Sirashurger, F. Noll, II.
Schenck, am! .■\. F. W. Schiimper, 339: Oliitiiary Notice of
I'ierre Duchartre, 344: \'ariations in Number of Stamens and
Carpels, L. II. Burkill, 359; Variation in Floral Symmetry
of I'oteiililla tormenti/la, .K. G. Tansley and K. Dale, 359;
Death of Marquis de Saporta, 370 : Death of Dr. F. Schmitz,
392: Obituary Notice of Nathanacd I'ringsheim, I). H. Scott,
399; .\luniina in I'lants, MM. Herthelot and .Xndrc, 407;
Volatile Constituents of Coca Leaves. Dr. P. v<^n Romburgh,
408: liidletin of the Botanical Department, Jamaica, 412;
Ksperintents with Dormant .See<ls, Dr. A. Peter, 422 ; the
.\buri Gold Coast Station, 423 ; Journal of Botany, 23, 430 ;
the Finger and Toe Disease, Geo. Massee, 453 ; Conspectus
Flora; -Vfric;!; ou Enimieration des Plantes d".'Vfrique, Th.
Durandet Hans Schinz, 459 ; Variaiiim in Caltha paliislris,
I'rof. T. D. .\. Cockerell. 487: .\ddition to Kew Gardens,
4,S9 ; Botanic G.ardens in South .\frica, 491 : Botanical
l',s|ndilion to .\sia .Minor, W. Siel)e, 513; Green Glass in
I'lani-IIouses, 514; Cassava as P'ood, II. W.Wiley, 515;
Death of Isaac Sprague. 53S ; Death of \. G. Mc.e, 538;
I'olyenibryony, M. Tretyakow, 540; Polyenibryony, Frank
I. Cole, 558 : a Popular Treatise on the Physiology of Plants,
I)r. Paul Sorauer. 554; the Terminal Flower in Cypcrace<c,
C. B. Clarke. 575 : a .Monograph of the Myceiozoa, being a
Descriptive Catalogue of the Species in the British Museum,
.\rthur Lister, 603 ; the (Jrigiu of the Cultivated Cineraria, W.
Hateson, F. U.S., 605

Boulliau (Ismael), First Mercury Thermometer used by, Abbe
Maze, 576

Bourne {(\. C. ), Zeit-und Streitfragen der Biologic, I'rof. Dr.
Oscar llerlwig, 265

]; pvey (Dr. II.),' Experiments on .Strength of Canadian Timber,
492

Brackett (S. H.), Magnetic Properties of Trillium, 158

Brady (G. Stewardson), the Natural History of the Sohvay,
322

Brandis (Sir D. ), a New Revision of the Dipterocarpeoe, ^14

Hrauner (Dr. B. ), .-\rgon in Nebul.v, 513; .\tomic Weight of

Tellurium, 620
Brazil, the New Capital of, H. Faye, 599

Bredichin (Dr.), the Perseid .Meteors, 301 '

Briggs (William), a Text-book of Dj-namics, a Text-book of '.

Statics, 76 ; an F^lementary Text-book of Hydrostatics, 509
Brigham, (R. P.), Drift Boulders between Mohawk and Susque- i

hanna Rivers, 525
Brightmore (.X. W.), the Principles of Waterworks Engineering,

I. II. Tudsbery Turner, 146
Brine (\'ice-.\(lmiral Lindesay), Travels among .American 1

Indians, their .Ancient Earthworks and Temples, 26
Hrinton (Dr. |. G. ), Death of, 251

Pritain, Twenty-five Vears of Geological Progress in. Sir
Archib.ald Geikie, F.R.S., 367 ; a History of Epidemics in,
Dr. Chas. Creighton, 579
British Birds, the Nests and i:ggs of Non-Indigenous, Charles

Dixon. ;o
P.rilish Birds, Claude W. Wyatt, 318
British Butterflies and Moths, W. Furneaux and W. I'. Kirby.

.?.>9
I'.ritish Central .\frica Protectorate, H. II. Johnstone. 66
llritish Museum Herbarium, .Xddidons to, 206
Uritish .Museum, a Monograph of the .Mycetozoa, being a

Descriiitive Catalogue c)f the Species in the, Arthur Lister,

603
British Races, Early, Dr. J. G. Garson, 67, 90
lirochet (.A.), .-\ction of Chlorine on Seccmdary .\Icohols, 264 ;

.\clion of Formaldehyde on .\mmoniacal Salts, 503
llrooke (Sir Victor), Sportsman and Naturalist, O. L. Stephen,

76
l;ro,.ker(A.), Electrical Engineering, 318: Problems .and Solu-
tions in Elementary Electricity and Magnetism, 580
brooklvn Summer School of Marine Biology, 537
Urooks ( Prof. W. K.), the Fauna of the Lower Cambrian, 423
lirorsen (Theodor), Death of, ^61
lirorsen's Comet, Comet 1894 I., (Denning) and, Dr. Hind, 302;

Dr. i:. Lam)!, 302

Brorsen's Comets, the Identity of Denning's and, 425

Brown _(.\ddison). Endowment for Scientific Rcse^tr'->i 01. 1 l'ii!i.
lication, 164, 186

Bruce (L. C. ), Dual Brain Action, 441

Brunache (P.), Le Centre de I'.Afrique ; -Autour du Tchad, 29

Brunhes (Prof. Julien), Death of, 488

Bruyn (M. Lobry de). Isolation of Free Hydrazine, NnH,, 544

Bryan (G. H.), Prof. Boltzmann and the Kinetic Theory of
Gases, 31, 152, 176, 319 ; a Text-book of Dynamics, a Text-
book of Statics, 76 ; Maxwell's Law of Partition of Energy,
262 ; Mechanical .Analogue of Thermal Equilibrium between
Bodies in Contact, 454 ; an Elementary Text-book of Hydro-
statics, 509

Buchanan (J. V., F. R.S.), on the Use of the Globe in the Study
of Crystallography, 184; the Relative Densities, &c. of
.-\tlantic and .Mediterranean Waters, 468

Buckland (William, D.D., F.R.S.), the Life and Correspondence
of, Mrs. (lordon, 457

Buckinan (S. .S. ), Instinctive -Attitudes, 31

Bulletin de r.Academie Koyale de Belgitjue, 46, 167, 477, 620

Bulletin de r.Academie Royale de St. I'eterstxjurg, 477

Bulletin of American Mathematical Society, 46, 167, 261. 430,

525- 573
Bulletin de la .Socicte de Naturalistes de Moscou, 334. 357
Bunbury (Sir Edward), Death of, 468
Burbury (S. H. F. I\..S.) Boltzn-.ann's Minimi:m Function, 7S,

320: the Ratio of the Specific Heats of Gases, 127 ; the

Kinetic Theory of Gases, 175
Burkill (L. H.), Variations in Number of Stamens and Carpels,

359
Burmese Chipped Flints, the, Pliocene not Miocene, Dr. W. T.

Blanford, F.R.S., 608
Burnside ( Prof W., F. R.S. ), the Theory of Groups of Finite;

Order, iii. and iv. , 478
Burrows (W. H. ), .Melhylisobutykacctic Aciil, 526
Burton (Dr. C. V. ), Subjective Lowering of Pilch of Note, 550 ;

(Objective Demonstration of Combination Tones, 550
Burton (W. K. ), the Water .Supply of Towns, 146
Butler (Gerard \V. ). De.alh-feigning in Snakes, 153
Butterflies: Butterflies from China, J.ajian, and Corel, J.)h;i
Henry Leech, 6 ; the Bird-Winged Butterfiie-, of the Eas.,
W. F. Kirby. 254, Robert II. F. Ri|)pr>n, 343; Butterflies
and .Moths (British). W. Furneaux, W. F. Kirby, 339: the
Black-Veined White Butterfly, W. Warde Fowler, 367,
H. Cioss, 391 ; Geographical Distribution (»f Butterflies, I'rof.
.Meldola, Dr. Sharp, F.R.S., and .Mr. McLachlan, F.K..S.,
478 ; New Indo-Malayan Butterflies, L. de Nic^ville, 500

Cailletet (L.), the Condens-ation of Electrolytic Gases by Metals

of Platinum Group, 95, 113
Cain (I. C. ), Incomplete Combustion of some Gaseous Carlwn

Compounds, 143
Calabria Ultra, Seismic Ili.story of. Dr. Mario Baratta, 468
Calderwood (W. L. ), Muscle Culture and the B.ail Supply, 578
California, the Mountains of. John Muir, 125
Callaway (Dr. C. ), the Barrenne.ss of Pre-Cambrian Rocks, 462
Caiman (H. T. ), Julina, New .Antarctic Compound .Ascidian, 213
C<i////rt /«/«-'■/'■/.', Variation in, Prof. T. I). A. Cockerell. 487
Cambier (R.), -Action of Form.aldehyde on .Anunoniacal .S.ilts, 503
Cambridge Philosophical Society, 95, 119, 167, 407, 431. 480
Cambridge (Rev. O. P., F. R.S. ), .American .Spiders and their
Spinning Work : a Natural History of the Orb- Weaving Spiders
of the United Stales, with sjwcial regard to their Indu.str)- and
Habits, Dr. Henry C. .McCook, 505
Camerer ( R. ), Total Reflection of Light in Dense Crystalline

Subst.ances, 357
Cameron (Jas.), Cod-liver (Jil .and Chemistry, K. Peckell .Mdller,

508
Camerton Explosion, Coal-dust an Explosive Agent, as shown

by an Examination of the, Donald M. D. Stuart, 268
Campbell (Mr.), the Supposed Magnetic F.atigue, 614
CamjibelMProf. W. W. ), the Spectrum of Mars, 1 32 ; the Satel-
lites of Mars, 443
Canada : Scientific Investigation in Cana<la, Dr. G. M. Dawson,
F.R.S., 236 : Canadian Geological Survey, 236 : Canadian
.Meteorological Service, 237 : Canadian Exiierimental Farms,
237 ; F^xperimenls on Strength of Canadian Timber, Dr. H.
Barrv, 492
Cancan'i (Dr. .A.), the Constantinople Earthquake of July 10
I 1894, 440

Indc.^

x

VStippUment to Xat.
L May 30, 1895

Omnibalism, Snake, H. Tsnagal, 321 ; Baron C. R. Osten

Sacken, 343 : J. Schrinlantl, 511
C.ii>acity for Heat. K. H. '."iritnths, II
Ca| ri Spcctroscopically Tcste-.l, the Blue Grotto of. Dr. 11. \\ .

Vogel, 300
Ca;)stick (Dr.), Ratio of Specific Heat in Com|iound Gases, 452
Can « in. the \'aporisalion of, Henri Moissan, 71
Ciricw (Major). Probable Cause of St. I'ancras Explosion, 440 ;

the London Electric Light .Main .\cciclenis, 539 ; Reimrt on

Southwark Bridge Explosion. 614
Carr (F. H.), Acetyl Dtri.atives of Benzaconine ami Aconitine,

Carus-\\ ilson (Cecil), Cleaning Tobacco Pipes, 51 1

Car%aUo (E.), the Laws of Cr>'stalline Absorption, 455

Cas>ava as Food, H. \i . Wiley, 515

C.i>-io]>eia;, f. 425

r;iMr.»ct Construction Coniixiny's Works at Niagara, Progress of

the, 109
Cat, M. Marey's Photographs of a Tumbling, 80
Cats, Movements in order 10 Fall on their Feet m.adc by, M.

Marey, 47
Catchpool (E.), a Text-lx)ok of Sound, 244
CicrpilLir Tree-plagues in Jamaica and Hong-Kong, 231
CiLrnfJ.), Electrostatic Ca|>acity of Rcsi-stance Bobbins, 407:

lOlectrostatic Caiacity of Resistance Coils. 442
Caves, Chinese Beliefs about, Kum.agusu Minakala, 57
Caves, Cows kept by .\rabs in. Colonel \. T. Frascr. 325
Caves and Swallow-Holes, E. .\. -Martel, Canon T .G. Bonney,

F.R.S., 410
Cayeux (L.) Remains of Sponges in Phiaiiites a{ Pre-Cainbrian

in Brittany, 3S4 ; Mineralogical Composition of Silex of Paris

Gypsum, 432
Ca'yley (Prof, .\rihur, F.K.S.), Death and Obituar)' Notice of,

323 : Funeral of. 344
Cecil (Henry), an (il>servation on Moths, 127
Cellular Pathology. I'ho onncrographic Metlwxl of Studying

Cell-Motion, Dr. C. L Leonard, 541
Cellular Physiolog)-. 59
("Lntur)- M.iga/ine, Science in, 259. 380
('•ihei. the .Spectrum of 5. .M. .\. Belopolsky, 21, 2S2
Ci'.ilil.ea, the Dawn of Civilisation, G. .Maspero, 122
Chambers (George F.), the Story of the Stars, 436
Chambers's Journal, .Science in, 259
Chaney (H. J.), English Weights and Measures, 422
<'h.i|iman (F.), Foraminifera from .Arabian Sea, 311
Char.actcr, -Acquired, Right Hon. Sir Eilw. Fry, F. R.S., 8,

197 ; Prof. E. Ray I^ankester, F. K..S., 54, 102, 245 : Edward

B. Poulton. F.R.S., 55, 126: Francis (lallon. F.R.S.,56; J.

T. Cunningham, 126, 293 ; John Cleland, 294
Charpy (G.), Boron Steel, 336; Levins de Chiniie, 459
fl'.iuveau (A.), a New .Vnlhrax Bacillus ( tV(ir7/<)r/«/'j), 622
Ch.iuveaud (M.), Development of Sieve-tuljcs in Angiospernis,

Chavanne ( L. ), the Ethereal Salts derived from Active Amyl
Alcohol, 144

Chemistr)-: a New .MethiHJof I'rep.aring Phosphoretted llyflrogen.
Prof. Retgcrs, 23 ; Study of Combination of I lydrogen
Fluoride with Water, R. .Metiner, 24 ; Researches on
Mercuric Sulphates, R.ioul \aret, 24 ; .Antimony Vermilion
not an Oxysulphide, II. Uaubigny, 24 ; Dr. Watt's Dictionary
of Chemistry, .M. .M. Pattison Muir and 11. Forster Morley,
27: Cartiazide and Di-urea, Prof. Curliusand Herr Heiden-
reich, 39; Reduction of .Sulph.ates by Specific Sulphide
FermenI, M. Beyerinck, 47 ; a Text-book of Inorganic
Chemistry, G. S. Newth, M. M. Pattison Muir, 52 ; Newth's
Inor^nic Chemistry, G. S. Newth, 106 ; M. .M. Palti.son .Muir,
107 : Eflccis of Cathinle Rays on Colour of Certain Salts,
Prof, (joldstein, 62, 406 ! the Pro|)erlies of Litpiiil Ethane and
Pro|nne, A. E. Tulton, 65; Researchrson Mercurial Nitrates,
Raoul \arct, 72 : Danger of Explosive .Mixtures of .Acetylene
and Oxygen, I'rof. L. Meyer, 84 ; the Explosion of a Mixture
of Acetylene and Oxygen, Dr. T. E. Thorpe, F. R.S., 106 ; the
ICxplosion of (Jascs in GI.-lss Vessels, I'rof. H.I!. Dixon. F. R.S.
Ijl : a Pure White DiSulphide of Tin, Dr. .Schmidt, 85 ; New
Method of obtaining Platinorhlorides, M. C. Lea, 93 ; .Active
Amylacclir ,\cid, Ida Welt. 95: the Oxidation <.f .Alcohols
h^- Fchling's .Solution, F. (iauil. 96 ; a New .Series of .Nitrogen
Com|Kiun(l.s, Prof. V. Pcchnian anil Herr Runge. 114 : a new
Element in the Nitrogen Group, A. E. Tutton. 25.S : Study of
Aliphatic Nitramincs, II. van Erp, J19 ; Liipiid Sulphuretted
Hydrogen, 130; Synthesis of Chlorides of Carljon during pre-

paration of Carbon Tetrachloride, Prof. V. Meyer, 131 ; Re-
determination of .Atomic Weights of Bismuth, Prof. Schneider.
131 : the Rekalion of Energy of Combination to Electrical
Knerg)', Dr. W. liorchers, 141 : Chemical Society, 143, 239,
310, 430, 454. 526, 620 ; the Proceedings of the Cho.nical
Society. Prof. William R.imsay, F. R..S. ,294; ihe.Anniversar)
of the Chemical Society, 534 ; Dr. .Armstrong's .Adilre.ss. 535 ;
a Product of .-Xction of Nitric Oxide on Sodium Ethylatc
G. W. Macdonald and O. Ma.s-son, 143 ; Incomplete Com
bustion of some Gaseous Carbon Com|xnMuls, \V. .A. Bone
and J. C. Cain, 143 ; Homologues of BulanetetracarlHixyiic
Acid and A<li|)ic .Acid, B. Lean, 143 ; Cellulose Sulphuric-
Acid, .A. L. Stem, 143 ; Condensation of Benzil with Ethyl
Malonate, F. R. Jajjp and W. B. Davidson, 143 : the Con-
version of Lactic .Acid into Propionic .Acid, Fernand Gaud,
144 : the Ethereal Salts deriveil from .-Xctive .Amyl .Alcohol.
P. A. Guye and L. Chavanne, 144 ; the so-called Organic
Chlorine of the Gastric Juice, II. Lescreur, 144; the Cor.
version of Black Mercury Sulphide with Red Sulphide. W
Spring, 167 ; Reducti; n cf .\luniina by Carlnui, Hem
Moissan, 167 ; Solubility of Ozrme, Abbe Mailfert, 16S :
Superpiisition of Optical Eftects of Different .Asymmetri
Carbon .Atoms in same .Active Molecule, P. .A. Ciuye and M
Gautier, 16S ; Isolation of .Anhydrous Hydrogen Peroxitk .
Dr. Wolffenslein, 1S2 : Colloidal Silver, C. Barus, 190: thc
X'arielies ()f Ciraphite. Henri .Moiss:in. 191 ; Pectaseantl Pectic
Fermentation, G. Berirand and .A. Mallevre, 191 : a Treatise
on Chemistry, .Sir H. Y.. Roscoe, F.K.S., and C. Schorlemmer,
M. M. Pattison Muir, 193: Phospherescence at very Low
Temperatures, M.M. Raoul Piclet and .Altschu), 206; Dis-
lilacemenl of Carbon by Boron or Silicon in Fused Cast Iron,
Henri Moissan, 240; the Chrt)mates of Iron, Charles Lejiierre.
240: New Reagent allowing Demonstration of Presence of
Hydrogen in Green I'l.ants, .A. Bacli, 240; X'alency of
Glucinum (Beryllium) and Formul.vof tllucina, .AIph-Cond)es,
240; .Study of Iron tiraphites, Henri Moissan, 263 ; Calciimi
Ethoxide, .M. de Forcrand, 263 : j8-Oxycinchonine, E.
Jungfleisch and E. Leger, 264 ; .Action of Chlorine on
.Secondary .Alcohols, -A. Brochet, 264 ; Physiological Pro.
perties of Oxalate and Crystalline .Salts of Nicotine, II.
Parenty and E. Grasset, 264 : Elementary (Qualitative Che-
mical .Analysis, Prof. Frank Clowes anil J. B. Coleman, 270;
Tables and Directions for the (Qualitative Chemical .Analysis
of Moderately Complex Mixtures of Salts, M. M. Pattison
Muir, 270 : I-aboratory Exercise Book for Chemical .Students,

E. Francis, 270 ; the .Atomic Weights of Nickel and Cobalt,
Prof. Winkler, 281 : Preparation of Graphites Foisonnants,
Henri Moissan, 287 ; (^Hialitalive .Separation of Nickel and
Cobalt. .\. \'illiers, 2S8 ; Inorganic Mode of Preparing Hydra-
zine, Dr. Duden, 301 ; Compound of Grape -Sugar with .\cid
Radicle of Hydrazine, Herr .Struve, 395 ; New Compounds of
Hydrazine with Fatty .Acids, .A. E. Tutton, 516 ; Isolation of
Free Hydrazine, N..H4, M. Lobry de Bruyn, .A. E. Tutton.
544 : the Commercial Synthesis of lllinninating I lydrocarbons,
Prof. \'ivian B. Lewes, 303 : Chemical Changes between Sea-
Water and Oceanic Deposits, Dr. John Murray and Robert
Irvine, 304 ; Pellitorine an<l l'i|>erovatine, W. R. Dunslan
and H. Garnett, 310; Adipic Acid and Derivatives, W. H.
Ince, 311 ; Action of Hydrogen Chloride on (^)uicklinie.
Magnesia, and Baryta, W. H. \'eley, 311 ; Melallic Tarlra-
seniles, G. (i. Henderson and .A. R. Esving, 311; l're|iara-
tion of .Amorphous .Silicon, M. \'igouroux, 312 ; I'ectase ami
Pectic Fermenlalion. G. Berlrand and A. Mallivrc, 312 ; the
Rise and Development of Organic Chemistry, Carl .Schor-
lemmer, 317: the Explosive Nature of the .Sodium and
Pota.s.siuni Derivatives of Nitromethane, A. E. Tutton,
328; the Production of the Glycolitic FermenI, R.
Lepinc, 336 ; Failure of Kjeklahl .Method for Eslima
tion of Nitrogen when applie<l to Chloroplalinates, M.
Delcpine, 336 ; a new System of .Anthracene, M. Delacre, 336 ;
Argon, 323, 337: .Argon, M. Berthelol, 384; .Argon. Dr. 1.
H. (iladslone, F.R.S., 389: Prof. Mendeleelf, on .\rgoii,
543 : the New Constitituent of the .Atmosphere, .Argoji.
L<jrd Rayleigh, Sec. R..S. , and Prof. William Kamsay.

F. R.S. , 347 ; on the Spectra of Argon, William Crooke^.
F.R..S.,354; H. F. Newall, 454 ; I'luorescejice Spectrum o!
Argon, Si. Hen helot, 622 ; the I.iipiefartion and Soliilificn
tion of .Argon, Dr. K. Olszewski, 355 ; Do Plants assimilaU
.Argvn ?, E. Hlass, 4(11 ; Prof. W. Ramsiiy, F. R.S., 461 ;
Argf)n and the Periodic System, Prof. J. I'anerson Reynolds,
F'.R.S., 4S6 ; Argon in Nebula-, Dr. H. Hranner, 513:

Siipflement to Xaiiire "1
May 30, T895 J

Index

XI

Attempts to produce Chemical Combinations with Art; .n.
.\[. Berlhclol, 527 ; Simple Dcmonslralion of Presence of
Argon in Atmospheric Nitrogen, M. Gunlz, 599 ; Argon not
in Vegetalile or Animal Substances, (!. W. MacDon.ilcl and
A. M. Kellas, 620; die Kesultate der Aetzmethode in der
Krystallcigraphischen Forschung, an einer Reihe von Krjstal-
lisirlen Ivorpcrn dargeslellt, Dr. H. Baimihauer, 340; Speed
of Liberation of Iodine in Mixed oUiiions, H. Schlundt, 346 ;
ihe New Iodine Bases, John McCrae and Mr. Wilkinson, 346 ;
Action of Diasta.se on Starch, A. R. Ling and J. L. Baker,
359 ; New a-Dibromocaniphor Derivatives, >L O. Korster,
359; .\c\A Siil])hate of I lydroxylamine, E. Divers, 359;
lIy|)ophosphites of Mercury and Bismuth, S. Mada, 359 ;
Kaniala (ii.), A. (\. Perkin, 359; Action of Aqueous Potas-
sium Cyanide on Gold and Silver in Presence of Oxygen, J.
S. Maclaurin, 359 ; Boride of Iron, Henri Moissan, 359 ;
Properties of Bismuth Sulphide, A. Dine, 359 : Action of
Electric Current on Kused Metallic Sulphates, Jules Gamier,
359 : Carljonyl Chlorobromide and Dibromide, .\. Besson,
359 ; Acetic Ethers from Sugars, C. Tanret, 359 ; Hexam-
ethylene-Amine, M. Delcpine, 360 ; Elementary Practical
Chemistry, Inorganic and Organic, J. T. Hewitt and F. G.
Pope, 364 ; Ihe Liquefaction of (iases, .M. M. Paitison Muir,
364, 388, 436; Prof. James Dewar. F.R.S., 365, 413; Am-
monium Thio-acetate as Substitute for Sulphuretted Hyilrogcn,
Prof. Schiff and Dr. Tarugi, 373 ; Moniodammoniuin Deriva-
tives of Hexamethyltriamidotriphenylmethane. .\. Rosenstiehl,
384 ; Reactions of Chelidonine with Phenols in Sulphuric
Solution, M. Battandier, 384 ; the New Laboratory at St.
Petersburg University, 392 ; Death of Dr. (ierhard Kriiss,
392 ; the Commercial Extraction of Pure Dextrose from
.Syrupy Mixtures, Dr. Wolff, 395 : .\ppIication of Sound-
Vil)rati(ms to .^nalysis of Two Gases of different Densities. E.
Hardy. 407 : .Alumina in IMants, MM. Berthelot and Andre,
407: Titanium, H. Moissan. 407: Lowering of Freezing-
Point of Dilute Solutions of Sodium Chloride, \. Ponsot, 407 ;
Sulphide of Gold, A. Ditte, 407; Cinchonigine, MM. E.
Jungfleisch and E. Leger, 407 ; the Lcyden Kyrogene Labora-
tory, Prof. Kamcrlingh (Jnnes, 408 ; Handbuch der Stereo-
chemie, Dr. C. A. Bischoff, 409 ; die -Maschinellen Hilfsmittel
der Chcmischen Technik, \. Parnicke, 412 ; the .\tomic
Weight of Tungsten, Prof. E. (i. Smith, 424 ; the .Specific
Heat of Tungsten, Prof. E. G. .Smith and Mr. Grodspeed,
424 ; .Action of Heat on Ethylic S-.\midocrotonate (ii.), J. N.
Collie, 430 ; Acidimetry of Hydrogen Fluoride, T. Haga and
\'. Osaka, 430 : Molecular Change in .Silver .\malgam, F. T.
Littleton. 430; Sul|ihocami>hylic Acid, II., W. H. Perkin,
jun., 430; .Acetyl Derivatives of Benzaconine an<l .\conitine,
\V. k. Dunstan aiul F. H. Carr, 430: .-Vccinitine ,\urichifir-
ides, W. R. Dunstan and H. \. D. Jowett, 430 ; .\tomic
Weights, I^'Co<i dc Boishaudran, 432 : .-Vmorphous Silicon,
M. Vigouroux, 432 ; Melting- Points of Mixture, H. Crompton
and .M. A. Whiteley, 454 ; the Volumetric Determina-
tion of Manganese. J. Keddrop and H. Ramage, 454 ;
Bromocamphoric ,'\cid, F. .S. Kipping, 455 : Elndlio-
scopic .Siuily of Colouring .Matters from Trijihonylmcthane,
\. Haller and P. T. Muller, 455 ; Combinations of
Nitric Oxide and Iron Chlorides, V. Thomas, 455 ;
Leyons de Chimie, H. Gautier et G. Charpy, 459 ; New
Method of Pre|>aring Unsaturated Hydrocarbon .-Mlylene,
Prof. Reiser, 471 ; Double Decompositions of Vapours,
Henryk .Ardowsky, 477 ; Black-Damp. Dr. John Haldane,
477 ' Compositirm i-*{ Extinctive .Atmospheres produced by
Flames, I'nif. Frank Clowes, 478 ; Production of Primary
-Amines, M. Delepinc, 480 ; Die Wissenschaft lichen Grund-
lagen der Analylischen Chemie, W. Ostwald, J. W. Rodger,
482 ; Sotlium Compoimds of Nitro-Parafhns, Prof A'ictor
Meyer, 492 : Action of Formaldehyde on Ammoniacal Salts,
,A. Brochet .and R. Cambier, 503 ; Optical Resolution of
a-Oxybulyrir Acid, P. .-X. Guye and Ch. Jordan, 503; Urea-
.ethanol, M. I'Vanchimonl, 504 : Magnetic Rotational Dis-
jiersion of ( )xygen and Nitrogen, Dr. Siertsema, 504: Cod-
liver (^il and Chemistry, F. Peckel .Moller, Ja.s. Cameron,
508: Terrestrial Helium (?), 512; Prof. Ramsay, 543;
W. Crookes, F. R.S., 543 : J. Norman Lockyer, C. B., F. R.S.,
586 ; Dimelhylkctohexamethylcne, F. S. Kipping, 526 ; U.se
i>f Barium Thiosuljjhatein .Starulardising buline S >lution, R. T.
Plimpton and G. C". Chorley, 526: Melting Pointsof Racemic
Mndiflcatinns and Optically .Active Isomerides, F. S. Kipj^ing
and W.J. Pope. 526 : Synthesis <if a- Methyl Butyrolactone, E.
Haworth aiwl W. 11. Perkin, jun., 526: .Mcthylisobutylacelic

.Aiiii. W. 11. Bcnlley and M. W. Burrows, 526; Action of
Nitruus (Jxide on Metals and Metallic Oxides, Paul Sabatier
and J. B. .Senderens, 528 ; Isomeric States of Oxides of
Mercury, Raoul Varet, 528 ; a Mercuric Combination of
Thiophene. G. Deniges, 528 ; Chemical C im|X)sition of
Oceanic Deposits, Prof. J. B. Harrison and .A. J. Jukc-
Browne, 527 ; Theoretical Chemistry from the .Standpoint of
Avogadro's Rule, and Thermodynamics, Prof. Walter Nemst,
.M. .M. Pattison .Muir, 530; the .Atomic Weight of Cerium,
F. .Schiitzenberger, 552 ; New .Method for Preparation of
Chkirojilatinous .Acid, Leon Pigeon, 552 : Heat of Formation
of Calcium Acetylide, .M. de Forcranil. 552 ; .Alterations in
.Saccharine Matters during Gcrminaticm of Barley, P. i'etit,
552 ; Chemical Process for Purification of Water, F. B*:>rdas
and Ch. (iirard, 552 ; Organic Chcmistrj', the Fatty Com-
l^ounds, R. Lloyd Whiteley, 557 ; Carbon Monosulphide, Dr.
Deninger, 564 ; Clases of Swimming Bladder f>f Fi.shes, Jules
Richard, 576 ; .Alcoholates of Lime and Baryta, M. de
Forcrand, 576 ; Qualitative Chemical .An.alysis of Inorganic
Substances, 580 : Grundziige der .Mathemaiischen Chemie,
Dr. G. Helm, 580: New Compounds of Phosphorus Nitro-
gen and Chlorine, II. N. Stokes, 592 ; Estimation of Thiophene
in Benzene, G. Deniges, 600 ; Calcium Phosphate of Milk,
L. Vaudin, 600 : an Improved Method for the Microscopic
Investigation of Crystals, .A. E. Tutton. 60S ; .Aromatic Esters
of .Arsenious .Acid, Dr. Fromm, 616; the Freezing Point of
Dilute Solutions, J. W. Rodger, 617 ; .\ssimilable Nitrogen in
.Arable Land, M. Pagnoul, 622 ; Methylene Lactate, Louis
Henry, 620 : Critical Temperatures of Mixtures and of Water,

F. \'. Dwelshauvers-Dery, 620 ; Action of Heat on Carbon
Bisulphide, Henryk .Arclowsky, 620: Atomic Weight ot
Tellurium. B. Brauner, 620 ; Studies in Isomeric Change,

G. T. Mciody, .A I„apworth, 620; Electrolysis of Potassium
AUo-Eihylic Camphorate, J. Walker and J. Henderson, 621 ;
Nitro Derivatives of Dimethylaniline. Dr. P. van Romburgh,
624; Addition Products of Symmetrical Trinitrobenzol, Dr.
P. van Romburgh, 624; Behaviour of Hydrogen to Palla-
dium at Various Temjjeratures and Pressures, Bakhuis Rooze-
boom and Dr. Hoitsema, 624

Chesney (General Sir George), Death of, 538

Chess- Players, Psychology of Mental Arithmeticians and Blind-
fold, .Alfred Binet, Francis Galton, F.K.S.. 73

Children, the Growth of St. Louis, William Townsend Porter,
Prof. Karl Pearson, 145

Chilo-.Argentine Earthquake of October 27, 1894, and Contem-
poraneous European Pulsations, 371

Chilo-.Argentine Earthquake of October 1S94, A. F. Nog\ie.s,

.393
China : Butterflies from China, Japan, and Corea, John Henry

Leech, 6 : Chinese Beliefs .about the North, Kumagusu .Mina-

k.ita, 32 : Chinese Beliefs about Caves, Kumagusu .Minakata,

57 ; Chinese Theories of the Origin of Amber, Kumagusu

Minakata, 294; Typhoons of 1893 in Chinese Seas, 130;

Superficial Deposits of Shantung, S. B. J. Skertchly and

T. W. Kingsmill, 478
Chlorine. New Compounds of Phosphorus Nitrogen and, H. N.

Stokes, 592
Chloroform at very Low Temperatures, .AnomalousBehaviour of,

Raoul Pictet, 20
Chorley (J. C. ), Use of Barium Thiosulphate in Standardising

Iodine .Solution, 526
Chree (C. ), Neotropic ELastic Solids of nearly Spherical Form, 46
Christiansen (C. ), the Origin of Frictional Electricity, 70
Chronograph Pendulum, a Simple, Carl Barus, 84
Chronometer Trials, V.'illiam E. Plmnmer. 153
Church (Prof.), Determination of Mineral Densities, 431
Cinelli (M.), the Transmis-sion of Electricity through Gases, 514
Cineraria, the Origin i>f the Cultivated, W. Bateson, F.R.S.,6oS
Civil Engineers, Instituti(m of, .Annual Banquet, 538
Civilisation, the Dawn of, G. M.aspero. 122
Clark (Prof. II. E.). an Elementary Textlwok of An.atomy, 412
Clarke (C. B. ). the Terminal Flower in Cyiieracex, 575
Clarke (Hvde), Death of, 468

Clas.sen (Dr. I, Improvement in Sensitive Balances, 540
H. Helm). Eleven-year Sun-spot Weather Peri

d and

Clayton ( 1 1

its Multiples, 436
Clayton (J.), Contraction of Trees caused by Cold, 462
Cleland (John), .Acquired Characters, 294
Climbingand Exploration in the Karakora.n- Himalayas, William

Martin Conw.ay, 196
Clouds, the Study of, 248

Ml

Indtw

CSnJfJiteiitrnl to Xtttur^,
^iff^ .o. 1895

CI' ".His, .Moiioii ami rormation uf, W. H. Shaw, K. R.S. , 527
Clowes (Prof. Frank). Elementary (Jualilaiive Chemical

Analysis. 270 ; Com]>osition of Extinctive Atmospheres pro-
duced liy Flames, 47S
Clowes (\V. 1,.), the Education of Naval Officers, 259
Coal-dust an Explosive Agent, as shown by an Examination of

the Camerton Explosion, Donald .M. D. Stuari. 26S
Ciickerell (Prof T. [). A.), \'ariation in Calllia palustns, 487
Cockle (Sir James, F.K.S.), Death of, 324
Ciid-liver Oil and Chemistry, F. I'eckel Miiller, las. Cameron,

ScS
Cohnstein (Dr.), the Mode of Foniiation of Lymph, 216 ; Action

of InlravenoiLs Injections of Sodium Chloride on Com|xisition

of L)-mph and Blood, 431
Cold, Contraction of Trees cause«i by. \. Clayton, 462
Cold, Intense, as a Thera|)eutic Application, Dr. Pictet, 5SS
Cold Days, the Occurrence of very, 416
Cole (Prof. ), Mutual Alterations of Basaltic Andesiie and Later

Eurite, 1 12
Cole (Frank J.), Polyembryony. 55S

Coleman (J. B. ), Elementarj- (Qualitative Chemical .•\nalysis, 270
CiilLardeau (E. ), the Condensation of Electroljtic Clases by

Metals of Platinum (iroup, 95, 113
Collie (). N.), Action of Heat on Ethylic /S-Amidocrotonate (ii.),

430
Collinson (John), Rain-making and Sunshine, 7
Colour- Blindness : a Case 01 Vellow-Blue Blindness, Dr. VV.

Pe<ldie, 335, 621 ; the Normal Defect of \ision in the Fovea,

C. L. Franklin, 615
Colour-Sensation, Ex|)eriments on, H. \V. \ogel. 469
CoLson (k. ), Conditions necessary to obtain Correct Results

when measuring Litjuid Resistances with Alternating Currents

and a Telephone, 280
Combes (.\lph. ), \'alency of Glucinum (Beryllium) and Formula

of Cilucina, 240
Comets: a Comet on the Eclipse, Photographs of, 1893,40;

Encke's Comet, Prof M. Wolf, 64 ; Return of Enckes Comet,

40: Ephemeris of, Dr. O. Backlund. 85; History of, \V. T.

Lynn, loS ; a New Comet, Mr. Edward Swift, 114, 132;

Ephemeris for Swift's Comet, 160 : Comet e 1894 (Swift), 542 :

Cometar)' Ephemerides. 207 ; Comet 1S94 I. (Denning) and

Brorsen's Comet, 425 : Dr. Hind, 302 : Dr. E. Lamp, 302 ;

the Designation of, 347
Commercial Cleography, E. C. K. Cionncr, 30
Concholf>gy : .Structure of Ga.stro|x«l Shells, \V. II. Dall, 181 ;

Foraminifera from Arabian .Sea, F. Chapman, 311
Conductivity of Pure Water, the Electric, J. W. Rodger, 42
Constantinople, .Seismological Observatory to be Founded at,

180
Constantinople Earthquakes of July 10. 1S94, Dr. Cancani, 440
Constituent, the New, of the Atmosphere, Lord Kayleigh, Sec.

R.S., and Prof. William Ramsay, F. U.S., 347
Consumption, Alpine Climates for, H. J. Hardwick, 54
Contem]X)rary Review, .Science in, 381
Contraction of Trees caused by Cold, J. Clayton, 462
Contraction, Muscular, on the Nature of. Prof Th. W. Engel-

mann, 519
Controversial Ceology, Joseph Prestwich, F.R.S., Prof. John

W. Judd. F.R.S., 601
Conway (William .Martin, F..S..'\.), Climbing and Exploration in

the Karakoramllimalayas, 196
Cooke (J. II.), the .Mahese Pleistocene Beds, 143
<' i"ke (Dr. M. C), Edilile and Poisonous Mushrooms, 8
' i-i^kI. a Flying, Dr. Ostroumo(i720 ; Captain Hendorff, 300
< 'I'lve (Dr. lienry). Death of, 538
Cop()et (.M. dc), Kedetenninalion of Tem|>erature of Greatest

Density of Water, 37
C iral : Studies of a (Jrowing .Vtoll, Dr. Hugh RoI>ert Mill, 203
Corca, Butterflies from China. Ja|un,and, John Henry Leech, 6

rnish (C. J.), Life at (he Z^m.. 276

n,i,h RiMks, the I'nvilved Prolilem of, Howard Fox, 36

rnu (Prof), Aeronautics in France, 29<j

' n;i, the Ultra Violet .Siwctrum of the, M. Deilandrcs, 589
vlf-n (Dr.), Cariliographir Researches on Mammals, 96
* kept in Cjivcs by Arabs, Colimcl \. T. Eraser, 325
I kcnlhr)r|>e (M,), a True London I'niversity. 161

ine (Agues), (Geological Distribution of Brachio|>oila, 514
Craniometry: the V'arictie.« of the Human S|)ecie-., Prof.

tiiuseppc .Sergi, 595
Crawford (J.), the Earthijuakc of November, 1S94, in Nicaragua

.ind llondura.H, 280

Creighton (Dr. Charles), a History of Epidemics in Britain, 579

" Critical Point," the, Raoul Pictet. 504

Croft (W. B.), Singing Water-l'ipes. 107: Simple Physical

.\p]Mratus. 383
Crommelin Collection of Dutch Birds, the, iS
Crompton (H.), Melting-points of Mixtures. 454
Crookes (W., F.R.S.), on the Sjjectra of .\rgon, 354 ; Terrestrial

Helium (?), 543
Crump (W. B.), Science Teaching in Schools, 56
Crustacea : a Flying Cope|X)d, Dr. OstroumoH", 20
Crystallography : Ibmiogeneity of .Structure the Source of
Cry.stai Symmetry. Wm. Barlow, 58 ; H. A. Miers, 79: Ink-
Crystals, 60 : on the Use of the tilobe in ihe .Study of Crys-
tallography, J. V. Buchanan, F. R.S.. 1S4; Willian! J. Pope,
223 ; Die Resultate dcr .\eizmethode in derkry.st.iUographischen
Forschung, an einer Reihc von krjstallisirlen Korpern dar-
gcstcllt. Dr. H. Baumhauer. 340: an Instrument for Cutting
Section-Plates and I'risius, .\. E. Tut;on, 452 : the Laws of
Crystalline .Misorption, E. Carvallo, 455 ; an Improveii
Method for the .\1 icroscopic Investigation of Crystals, A. E.
Tutton, 608
Culverwell (EdHar<i P.), a Criticism of ihe .\stronomical Theory
of the Ice -Xge, 33 ; the .\stronomical Theory of the Ice .\ge,
371; the Kinetic Theory of Cases, 78; Prof. Boltzmann's
Letter on the Kinetic Theory of Clases, 581 ; Boltzmann's
Minimum Theorem. 105, 246
Cunningham ( Lieut. -Colonel .\llan), on Mersenne's Numbers, 533
Cunningham (J. T. ), .Vcquired Characters, 126,293; 'l^"-' ^'•'"

tistical Investigation of Evolution, 510
Curie (M.). Experiments to see if Light Rays deviated by Mag-
netic Field, 394
Currents, Ocean: ihe Travels of Three Bottle- Papers, H. C.

Kus-sell, 35
Curtis (ProT. ti. E.), the Wind and Birds' Flight, 156
Curtius ( Prof ), Carliozide anil Di-urca, 39
Curve, the Examinaiion, Prof. C. Lloyd Sli>rgan, 617
Cycles, Involution and Evolulion according to the Philosophy

of, 125
Cyclop;vdia of Names, the, 434

Cypress of Nyasalaml, the New. S5 : W. T. Thisehon-Dyer,
F.R.S., 175

D.T.'mme \and Glacier Lake, the, Capt. Ferryman, 130
Dahms (.Mbert), Freezing Points of Binary Mixtures of Helero-

morphous -Substances, 619
Dale (IC. ), \ariations in Floral Symmetry of I'olcnlilla Tor-

nientilla, 359.
Dall (W.H.), Structure of Gastropod Shells, 181
Dana (Dr. C. L.), (oantsaiul Giantism. 381
Dana (Prof lames Dwight), Death of, 587 ; Obituary Notice of,

611
Danckelmann ( Prof von). Dr. Sleinlach's Observations on the

Climate of Jalu, 192
Darriens (G.), Chemical Reactions in Ordinary Lead .\ccumu-

lator, 37
Darwin (Francis, F. R.S.), Practical Phy.siology of Plants, 577
Daubree (M.), Statistical .\ccouni of French Fores,s, Prof VV.

R. Fisher, 64
Daubree (Prof), llayden Medal awarded to, 345
Dauphine, the Uake of, .\. Delebecipie, 35
Daviilson (W.B.), Condensation of Benzil with Fthvl Malon.ite,

'43

Davis (Prof J. R. .\inswiirth), the Habits of Lim])ets, 511

Davison (C), on a Remarkable Eailhquake Disturbance ob-
served at .Strassburg, Nicolaiew, and Birmingham, on June 3,
1893, 208; the \'eloci(y of the .Argentine Earthipiake" Puls;i-
lions of October 27, 1894, 462 ; the Age of the Earth, 607

Dawkins (I'rof W. Boyd, F.R.S.), .Man, the Primeval Sav;ige,
Worthington G. Smith, 194

Dawn of Civilisaiion, (he, G. .Maspero, 122

Dawson(Dr. (.i. M., F.R..S.), Scientific Investigation in Canada,
236

Days, Ihe Occurrence of verj- Cold, 416

Dealh, (he I'eigning of, in .Snakes, R. Harry \'incent, 223

Death, Longevily anil. Dr. ti. J. Romanes, 381

Dechevrens (Re\. Marc), Mixlifications of an Electrical Anemo-
meter, 326

Deherain (P. P.), Autumn Cultivation of Green Manure, 311 ;
the Com]>i»sition of Drainage Waters, 576

Delacre (M.). a New .System of Anthracene, ^},U

May 30, 185s 1

Judex

Xlll

Delelwcque (A.), the Lakes of Dauphine, 35

Ueleiiine (M.). Kaihirc of Kjcldahl, Method of Estimation of
Nitrogen when apphed to Chlorojilatinates, 336 ; Hexa-
methylene-Amine, 360: I'roduction of Primary Amines, 478

Deniges (('•.), a Mercuric Combination of Thiophene, 528;
Estimation of Thiophene in Benzene, 600

Deninyer (Dr.), Carbon Monosulphide, 564

Denning (W. K. ), Jupiter, 227; the I'erseid Meteors, 320;
Denning's Comet, 1894 I. and Urorsen's Comet, Or. Hind,
302 ; Dr. K. Lamp, 302 ; the Identity of Denning's and
Brorscn's Comets, 425

Denza (P'ather K. ), Obituary Notice of, 179

Desaint (H.), Functions Lntieres, 503

Deserts of .Southern I'rance, the, S. Baring-dould, Canon
Bonney, K.K.S., 100

Designaticm of Comets, the, 347,

Deslandres (H.), Kadial Velocity of j," Hercules, 263 ; Spectro-
scopic Measures of I'lanetary Velocities, 443 ; Ultra-Violet
Radiation of .Solar Corona during total Eclipse of .April 16,
'893, 575 ". the Ultra-Violcl S])ectrum of the Corona, 589

Ucwar (I'rof. James, K. U.S.), the Liquefaction of Gases, 245,

365- 413
Deyrolles Nickel Entomological Fastening Pin, 130
Diameter of Neptune, the, I'rof. Barnard. 617
Diameters of Mercury, the -\pi)arent. Prof. Barnard, 373
Dickson (Dr. Walter, K.N.), Death of, 61
Dickson's i'hysical Investigations in Karoe-Shetland Seas. 115
Dilute Solutions, the Freezing Point of, J. W. Rodger, 617
Dines (W. H.), Cause of Cyclones of Temperate Latitudes, 451
Dinse (P.), the .Morphology of Fjords, iii
Diphtheria, the Antitoxic Serum Treatment of. Dr. M. A.

kuffer, 16; Dr. C. Sims Woodhead, 402,425 ; the .Anti-toxin

Trea'nient of l)i]ihtheria in France, 83 ; Protest against New

Treatment of Itiphtheria, 156; Statistics of Results of

Behring and Roux's Method. 324
Discontinuous Motion, A. B. Basset, F.R.S., 11
Diseases of Trees, Text-book of the. Prof. R. Harlig, Prof.

\V. R. Fisher, 28
Disinfectants, .Air, Water and, C. M. .Aikman, 412
Disinfection by Copper Sulphate of F'lecal .Matter. 11. X'iniciU.

168
Dispersion, Atmospheric, Dr. Kambaut, 396
Ditte (.A.), Properties of Bismuth Sulphide, 359; Sulphide of

(lold, 407
Divers (E. ), -Acid Sulphate of Hydroxylamine. 359
I )ixon ( .A. F. ), Development of Branches of Fifth Cranial Nerve

in Man, 599
Dixon (Charles), the Nests and Eggs of Non-Indigenous British

Birds, 30 ; New Law of Geographical Distribution of Species,

.545
Dixon (Edward 1. 1, Peculiarities of Psychical Research, 200,

223 : the Expansion of Functions, 308
Dixon (Prof. H. B., F'.R.S.), the FZxplosion ol Gases in (JIass

\'essels, 151
Dixon (H. H.), the .A-scent of Sap, 93
Dixon (Samuel), Drilling Machines for Boiler .Shells, 22
Djakonow (D. ), DieBearbeitung desGlasesaiif dem Blasetische,

580
Dogs' Eyes, .Spots over, Worthington G. .Smith, 57
Dogs" Eyes, Tan-spots over, J. Shaw, 33 ; S. S. Peal, 533 ; Dr.

Alfred R. Wallace, F.R.S., 533
Donnan (F. G.), " Solute," 200
Donnelly (.Major-Cleneral Sir John) on Technical Education,

116
Dopplcr's Principle, Dr. Belopolsky, 233
Dor.sey (Prof. J. O.), Death of, 392

Drainage Waters, the Composition of, P. P. Dehcrain, 576
Drift-Bottles in the Irish Sea, Prof. W. .A. Herdman. F. R.S..

'5' . .

Drude (P.), .Studies of Electric Resonator, 190; Electric Dis-
persion, 406

Dul)lin, a Foucault Pemlulum .at, W. R. W'estropp Roberts, 510

Dublin Royal .Society, 502, 622

Dubois (F;. ), Pithecanthropus Erectus, eine Menschenaehnliche
Cebergangsform aus Java, 291 : so-called Mis.sing Link, 428 :
Dubois on Pithecanthropoid Remains in Java, .Sir W. Turner,
619

Duchartre (Prof. P.), Death of, 35 ; Obituary Notice of, 344

Duckworth (W. L. H.), New Ossiferous FLssure in Cresswell
Crags, 527

Duden (Dr.), Inorganic Mode of Preparing Hydrazine, 301

Dudley Observatory, the New, 327

Dumesnil (C), Tableau Mctrique de Logarithmes, 386

Dunkeld, Original Larch Trees at, 11 1

Dunstan (W. R. 1, Pcllitorine and Pipcrovatine, 310 ; Acetyl

Derivatives of Benzaconine and Aconitine, 430; Aconitine

Aurichlorides, 430
Duprc's (Dr.) Rejiort on the Compressed Oxygen Cylinder

t^xplosion, 562
Durand (Th. ), Conspectus F'lone Africx, ou Enumeration des

Plantes d'.Afrique, 459
Dutch Birds, the Crommelin Collection of, 2, 18
Dyeing : La Pratique du Tcinturier, Jules Gar9on, Walter M.

Gardner, 604
Dynamics : a Text-book of Dynamics, William Briggsand G. H.

Bryan, 76 ; the F'oundations of Dynamics, Prof. G. F.

Fitzgerald, F'. K.S., 283; Dynamometers and the .Measure-
ment of Power, John J. Flather, 30

Early British Races, Dr. J. (\. Garson, 67, 90

F:arth, on the .Age of the. Prof. John Perry, F.R.S., 224, 341,
582: I'rof. Tail, 226: Lord Kelvin, P. R.S., 227, 438; Prof.
W. J. Sollas, F.R.S.. 533, 558 ; Dr. Bernard Hobson, 558 ;
Dr. -Alfred R. Wallace, F.R.S., 607 ; C. Davison, 607

Earth, the Plane., an -Vstronomical Introduction to Ge<^raphy,
R. .A. CJregorj', 291

Earih-Wavcs and \'il)ra;ions, the Observation of, Prof. John
.Milne, F.R..S.. 548

Earth-Worms, Rhynchodemus Terrcs-.ris in Germany, II.
Simroth, 294

Eanhquakes : the Chilo-.Argentine Eanh<|uake of October 27,
1894, 18 ; .A. Y. Nogues, 393 ; Connection between Contem-
porary F;uropean Pulsation Series am!, 232, 371 ; the Velocity
of the .Argentine Earthquake Pulsations <if October 27, 1894.
C. Davison, 462 : Earthquake in New Hebritles, 61 ; in
Sicily, 82, 513 ; the .Sicilian Earthquakes of August 1894, Dr.
M. Baratta and Prof. Ricco, 207 ; Earthquakes in Italy, no,
513, 587 ; the South Italian Earthqu.ake of November 16,
1894, I'rof. Tacchini, 346: in Vienna, no; F'arthquake in
Hungary, 206: in .Austria-Hungary, 587; Catalogue of
Earth(|uakes in Russia, .Mushketoff and (jrloff, 181 ; on a
Remarkable Earihcpiake Disturlxince observed at ,Stra.ssburg,
Nicolaiew, and Birmingham, on June 3. 1893, C. Davison,
Dr. E. von Rebeur Pa.sch»itz, 208 ; Earthquake of Novem-
ber 1894 in Nicaragvta and Honduras, J. Crawford, 2801
Earthquake in Persia, 298; in Norway, 344: Dr. Hans
Reusch, 390 : Dislocation of Sumatra Mountain System by
Earthquake of .May 17, 1892, J. J. .A. Muller, 408 ; the .Afier-
.Shock of lvar;hquakes, F. Omori, 423 ; the Constantinople
Earthquake of July 10. 1894, Dr. Cancani, 440; F;arthquake
in Pacific Ocean. 468 ; the Frequency of Earthquakes, M. de
Montessus de Ballore, 540 ; the Tokio Earthquake of June 24,
1894, 563

East, the Bird-Winged Butterflies of the, H. F. Rippon. 343

Ea-ston (C. ). the Milky Way, 327

Eaton (Dr. Darwin G.), Death of, 53S

Eclipse of the .Moon, 444, 472

Eclipse of the Sun, .March 26, Partial, 493

Eclipse, Total, by Order of the Sun 10 Chile lo see his, .Vpril
16, 1893, J. J. .Aubenin, lOI

I{!clip.se Photographs of 1893, a Comet on, 40

Eder (J. .M. ), Studies of Bun.sen Flame .Spectra of .Alkali ami
.Alkaline Earih .Metals, 20

Edible and Poisonous Mu.shrooms, Dr. M. C. Cooke, 8

Edinburgh, the Royal Observatory, 493

Edinburgh Royal .Society, 215, 335, 621

I'dridge-Green (Dr. F. W. ), the .Artificial Spectrum Top, 321

Edser (E. ), Objective Reality of Combinalion Tones. 550

Education : Science Teaching in .Schools, W. B. Crump, Gr.acc
Heath, 56: Geoaietry in Schools, Edward M. I«ingley, 1 76:
a True University of London, M. Crackenihorpe, 161 ;
EiUication of Naval Officers, the, W. L. Clowes, 259 ; the
Teaching University for Lon<lon. Dr. W. Palmer Wynne, 297;
Research in I'diicalion, Dr. II. F^. .Armstrong, F. K..S. , 463;
Dr. M. I'osler on the Teaching of Physiology in Schools, 4S7:
the New Technical Educator, vol. iv., 53; .M.ajor-GenemI
Sir John Donnelly on Technical I'ducalion, n6 ; Technical
Education, Science Teaching, H. Ci. Wells, 182 ; the -Advance
of Technical Eilucation, R. .\. Clregory, 379

Egypt, the Nile Reservoir at .As.sam, no: the Nile, Sir Colin
Scolt-.Moncrieff, 444

XIV

Index

CSup^ement ti> Satnre,
May 30. 1895

Kg>-ptol<^- : the Dawn of Civilisation— Eg)-pt and Chaltlrea, C"..
Maspero, 122: Death anil (ibituar)- Notice of K. S. Poole, ,
370; Death of Dr. 1". J. L;iiith, 421

Kifiel Tower, Kicchlin's Wind Measurement Experiments at,
Max de Nansouty, iSl

Klectricity : Force acting at Surface of Separation of Two
Dielectrics, H. Pellat, 24 ; Electric Light and Power,
Arthur K. Guy, 30; the Electric Conductivity of Pure Water
J. W. Rodger. 42 : Chemical Reactions in Onlinary Lead
Accumulator. G. Darriens, 37 ; the Constitution of the Electric
Arc, L. Thomas, 47 ; Effect of Cathmle Rays on Colour of
Certain Salts, Prof. Goldstein, 62 ; Production of Cathode
Rays, J. de Kowalski, 512 ; Conditions necessar)' to Production
of Cathode Rays, M. ile Kowalski. 394: Effect of Cathwie Rays
on some Salts, E. Goldstein, 406 ; the Kerr Phenomenon, C. H.
Wind, 62, l68; the Origin of Erictional Electricity, C.
Christiansen, 70 ; Thermo-Couples of Metals ami Saline
Solutions, .August IIagenl)ach, 70; Changes of Length pro-
duced by Magnetbation, H. Nagaoka, 70; Elliptically
Polarised Rays of Electric Force, L. Zehnder, 70 ; Refraction
and Dispersion of Ra)-s of Electric Force, .A. Garbasso and
E. Aschkinass, 70 ; Resonance Analysis of .Alternating
Currents, M. J. Pupin, 93, 190: the Condensation of
Electrol>-tic Gases by .Metals of Platinum Group, Cailletet
and Colar<leau, 95 ; Condensation of Gases produced by
Electrolysis on Platinum and Palladium Electrodes, .MM.

Cailletet and Colardeau, II

Influence of Polarisation on Out-

flow of Negative Electricity caused by Light, Prof. Boernstein,
95 ; Progre.ss of the Cataract Construction Com|)any"s Works
at Niagara, 109 ; the L'tilisation of Ni.igara Falls, Prof. Cieorge
Forbes, F.R..S.. 205: the Relation of Energy of Combina-
tion to Electrical Energy, Dr. W. Borchers, 141 ; a Modifica-
tion of Ballistic Galvanometer Method of Determining
Electromagnetic Capacity of Condenser, M. Womack, 142 ;
Student's Ap|)aratus for Verifying Ohm's Law, Prof. Ayrton,
142 ; New .Slethod for Measuring .Small Resistances, Dr.
I'asqualini, 158; Temperature of F^lectric .Arc, J. Violle,
168; Electromagnetic Theorj', Oliver Heaviside, F. R.S.,
J. Swinburne, 171 : New Interruption for Large Deduction
Coils, F. L. O. W.adsworth, 190; Thermoehemical Process
in Secondar)- Cell, Franz .Streinz, 190 ; .Magnetisation of Iron
and Nickel Wires by Rapid Electric Oscillations, Ignaz
Klemencic, 190; Studies of Electric Resonator, P.
Drude, 190 ; Distance Telegraphy without Wires, Dr.
Rubens, 191 ; Determination of Specific He.at of Water in
Electrical Units, Prof. .A. Schuster, F. R.S., and W. Gannon,
214; Meth'jd of .Measuring Sjiecific Inductive C.ip.icity and
Resistance of Liquids, Prof. Nernst, 232 ; Tests of Glow
Lamps, F'rof. W. E. .Ayrt(m and E. A. Medley, 239, 358 ;
Electric Potentials in Liquid Conductor in Uniform Move-
ment, G. G. de X'illemontce, 240 ; Electrostatic Cii>acity of
Line Transversed by Current, Si. A'aschy, 240 ; Electrical
Vibrations in Con<lensing Systems, Dr. J. Larmor, l'".R.S.,
263 ; Conditions nece.ssary to obtain Correct Results when
Measuring Liquid Resistances with .Alternating Currents
and a Telephone, R. Colson, 280; Thermo-Electric l'ropi;rlies
of Platinoiil and .Manganine, li. D. Peirce, 280 ; Influence
of Electric Wave', on Galvanic Resistance of Metallic Con-
ductors, Dr. Aschkinass, 28S ; IClectrolysis of Solution of
Mix.'d Nitrate and Sulphate fif Silver plus a little Nitric Acid,
Dr. Gross, 288; some Early Terreslial .Magnetic Discoveries
jwrtaining to Englaml, Will Whislon, L. .A. Bauer, 295 ;
Eleclriral Distribution on Two Intersecting .Spheres, 11. M.
Maolonald, 30S ; P,ass\ge of f Jscillator Wave-Train through
Plate of Cinilucting Dielectric, G. N. Vule, 310;
Electrical Engineering, W. Slingo and .A. Brooker, 318;
Standard Methinls in Physics and ICleclricily Criticised, II.
A. Naber, 318; Elect roscoiK-s in Lecture, Prof. Oliver J.
lynlge, F. R.S., 320: J. Regmald .Ashworth. 343 : the Elihu
Thomsfin Prize, 324 ; Modifications of an Electrical .Anemo-
meter, Rev. Marc Dechevrens, 326 ; Electromagnet Pull,
Max Weber, 326, 357 ; Electric Discharge through Ga.ses,
Prof. J. J. Thomstjn, 330 ; Capillaiy ICleclromelers and Drop
ElectriKles, (i. .Mever, 334: Different Forms of Multiple
Rewmance. V. Bjerknes, 357 : .Action of ICIeclric Current on

j.„, . 1 \!.. .11. w.c. I lulesGarnier, 359; Lcs Oscillations

El . Prof. A. Gray, 361 : the Tin

CI - Skinner, 383 ; ExpLTiineiils to .see if

Light Rays deviaieil by Magnetic Field, 394 ; Potential
(>radicnt in Positive Portion of Glow Dl.scharge, A. Herz,
4o5 ; Unipolar Induciion, Ernst Lecher, 406 ; Electric

Dispersion, P. Drude, 406 ; Electrostatic Capacity of Rcsisi
ance Bobbins, J. Cauro, 407 ; Double Refraction of Electric
Waves in WockI, K. Mack, 423 ; Method of Determining
ConductiWties of Badly-conducting Substances, Prof. J. J.
Thomson, 431 ; Probable Cause of St. Pancras Explosion,
Major Cardew, 440 ; Major Cardew on the London Electric
Light .Main .Accidents, 539 : Major Cardew's Report on the
Southw.irk Bridge Explosions, 614; the St. Pancras Electric
Light Main Explosion. 562 ; Electric Light Main Explosion at
Providence, Rhoile Island, 562 ; F'lectrostatic Ca|)acity of
Resistance Coils, J. Cauro, 442 ; Electromotive Force of
Iodine Cell, A. P. Laurie, 454 : Electrical ILiuKage at Earnock
Colliery, R. Robertson, 469; Water- Power applied by
IClectricity to Gold-Dredging, Robert Hay. 470 ; the Telegra-
phist's Guide, James Bell. 4S4 ; Electriticalion of .Air and
other t_lases. Lord Kelvin, P. R.S., Magnus Maclean, ami
.Alexander (.'.alt, 495 ; .Action of Light in Producing Electric
Discharge through \'acuum Tube. Klster and Geitel, 514 ; the
Transmission of Electricity through tlases, G. Vincentini and
M. Cincelli. 514; the United States Units of Electrical
Measure, 518; a Class of Secondary Batteries, Lucien
Poincare, 528 ; Thermoehemical Carbon Battery, Desire
Korda, 528, 541 ; Therapeutic .Action of Currents of High
Frequency, .Apostoli and Berlioz, 528; Elect rophysiologie.
Prof. W. Biedermann, Prof. J. Burdon Sander.stm, !•'. R.S.,
553 ; a Battery with Liquid .Metallic Electrodes, Luciei;
Poincare, 563 ; a New Determination of the Ohm, F'.
Himstedi, 571 : the Diselectrification of .Air, Lord Kelvin,
Magnus .Maclean, and .Alexander Gait, 593 : the tjueslion iif
Dielectric Hysteresis, .A. W. Porter and I). K. Morris, 574 ;
Problems and Solutions in Elementary Electricity and .Magne-
tisin, W. Slingo and .A. Brooker, 580 ; Electrical Resistance
of Woods and Stones, B. O. Peirce, 588 : the Supposed
Magnetic Fatigue, .Messrs. Campbell and Lovell, 614;
Electrolysis of Pot.assium .AlloElhylic Camphorate, J. Walker
and J. Henderson, 621 ; Carbon Monoxide produced by
Combustion in FZIectric .Arc, N. Grchant, 622: Comluction
and Convection in Feebly Conducting Dilute Solutions,
E. Warburg, 619 ; Glow Discharge in Air, C. .A. Mebius,
620 ; the Testing of Platinum Pyrometers, Dr. W. Wier,

623
Elgar (Dr. Francis), James Watt and Ocean Navigation, 475
Elliot (G. Y. Scott): Return of, 298 ; Exploration at Ruwen-

zori, 271 ; the Glaciation of Mt. Ruwenzori, 441 ; Exploration

of Mt. Ruwenzori, 527
Elliott (.Surg.-Capt., R..\.). Strychnine no .Antidote to Snake-

Pttison, 540
Elliptical Orbits, Mr. II. I.arkin, 234
Elster ( Herr), .Action of Light in Producing Electric Discharge

through Vacuum Tube, 514
Embryology : Death of Prof. J. .A. Ryder, 587
Emin'Pasha, the Death of, R. D. Mo'hun, 381
F^nargite, Mr. Spencer, 621
Encke's Comet, Prof .M. Wolf, 64 ; Return of, 40; l^phemeri>

of Dr. O. Backlund. 85: History of, W. T. Lynn. 108
Energy of Combination, the Relation of, to Electrical Energy,

Dr. W. Borchers, 141
Engelmann ( Prof Th. W. ) on the Nature of Muscular Contraction,

S'9
Engineering : the I'.lemenis of Graphic Sialics, L. M. Iloskms,
7; Institution of Mechanical Engineers, 22, 377 ; .Manufacture
of Standard Screws for .Machine-made Watches, C J. Hewill.
22; Drilling Machine for Boiler .Sliells, Samuel Dixon, 22 ;
Dynamometers and the Measurement of Power, John j.
Flalher, 30; Helical Gears, a Foreman Pattern-Maker, 30 :
Ricour's Ex|x;rimenls to Overcome .Air Resistance to Loco
motive at High .Speed, Max de Nansouty, 62 ; the Construction
of the Modern Locomotive, George Hughes, N. J. Lockyer,
97 ; Progress i>f the Cataract Construction Company's Work^
at Niagara. 109 ; on the Development and Transmission •
Power, Prof William Cawthorne Unwin, F.K..S., 124; .A^
vice to Voung Engineers, A. Siemens, 131 ; the Principles ^
Waterworks ICngineering, J. H. Tudsbcry Turner and .A. \\
Brightmore. 146; the Water Supply of Towns, W. K. Burtm .
146 : the .Mechanism of Weaving, 1 . W. l''ox, 149 ; the .Stean
ICngine and other Heal Engines. Prof. J. .A. Ewing, F.R.S.,
219: .Measurement Conversion Diagrams, Robert H. Sniilli,
221 ; Electrical Engineering, W. .Slingo and .A. Brooker, 31S ;
Death of Hermann liruson, W4 : 'he Determination of tl:r
Dryness of Steam, Prof. W. C. Unwin, F.R.S., 377 : Deail
of Alfred Giles. 468; Death of J. C. Smith, P.Inst.C.E.,

SiifipUmcitt to .\a/«n",l
May 30, 1895 J

Index

xv

Irclanil, 48S ; Naval Knginecring, the Limitations of Screw
I'njpulsion, J. I. Thornycroft, K.K.S., and S. \V. Bamal)y,
562 : Institution of Civil Engineers, Annual Banquet, 538
r.iigland, Khyndwdetints terrcslris in, V . W. Cianible, 33;
scinie I'arly Terrestrial Magnetic Discoveries pertaining to,
Will Whiston, L. A. Bauer, 295; the Development of Tele-
graphy in, 324
Ijitcnncilogy : Butterflies from China, Japan, and Corea, John
Henry Leech, 6 : Develoi)nient of Lungs of Spiders, O. L.
Sinimims, 37; Enroniological Society, 46, 94, 190, 311,
430, 479. 501, 551, 575 ; an Oliservation on Moths, Dr. L. C.
Jones, 79; Henr}' Cecil, 127 ; More alxnit Moths, Dr. L. C.
Jones. 321 ; Forn\ica Sniaragdina, Mr. Ridley, 95 ; Origin of
Classes among the " I'arasol" Ants, 1 lerbert Spencer, 125 ;
Deyrolle's Nickel Fattening I'in, 130 ; Pigments of Pierid.-e,
K. C;. Hopkins, 142; the Warhle Fly, \V. !•'. Kirby, 154; a
Swarm i>f Bees in December, 230 ; the Bird-Winged Butter-
flies of the East, W. F. Kirby, 254; Robert H. F. Rip|>on,
343 : Butterflies and .Moths (British), W. Furneaux, W. !•'.
Kirby, 339 ; the Black-Veined White BulterHy, W. Warde
Fowler, 367 ; H.C;oss,39I ; Geographical Distribution of Butter-
flies, Prof. Meldola, Dr. Sharp, F.R.S.,and .Mr. McLachlan,
F.R.S., 479; New IndoMalayan Butterflies, L. de Niceville,
500 ; the Spinning tdands in Phrynus, H. >L Bernard, 263 ;
Injurious Insects, Eleanor A. Ormerod, 471 ; Entomology in
.\nKrica, I.. P. Howard, 490 ; <,)ueslions bearing on Specific
Stability, Dr. Francis (lalton, F.R..^., 570; New Species of
Termites found by Dr. Haviland, 575
Eocene Fossils at Murren, Right Hon. Sir lohn Lidibock,

F. U.S., 223
F.|iideniics : a Hi.'to-y of Epidemics in Britain, Dr. Chas.

Crelghton, 579^
Fjiigenesis or Evolution, Prof. Dr. Oscar Ilcrtwig, H, C,

HiKirne, 265
V.\\i (H. van). Study of Aliphatic Nitramines, 1 19
l'".spin (Kev. T. E.), Two Variable Stars. 40 -. a New Star, 161
Essex, Remarkable Oak Trees in, J. C. Shenstone, 280
FUhane, Liquid, the Properties of, and Propane, A. E. Tutttm,

Ethnography : Internationales Archiv fiir Ethnographic, 525,

57,?'
I

ethnography : Internationales

57,?'

thnology : Death of Lieut,
l-'arly British Races, Dr.

Colonel Garrick Mallery, 61 ;
G. Garson, 67, 90: .\lbum von
Papua- Typen, .\. B. Meyer and R. Parkinson, 174; Death of
Prof. J. O. Dorsey, 392

luimorfopoidos (.Mr. ), Determination of Thermal Conductivity
and Emissivity, 310

I'.vans (Maurice S.), the Fertilisation of l.oraulhiis kraiissiatnis
and /,. tliri^L'i. 235

l!v.)lution : Involution and Evolution according to the l'hilo.so-
phy of Cycles, 125 ; Epigenesis or Evolution, Prof. Dr. Oscar
Ilcrtwig, G. C. Bourne, 265: \ariation in .Xnimals and
Plants, Prof. W. F. R. Weldon, F.R.S., 449: Organic
Reason of Failure of Bateson's and Galton's Theories of Evo-
lution, Dr. ,\. R. Wallace, 450: the Statistical Investigation
of l\\'ohiiion, f. T. Cunningham, 510

E«ing(.\. K.), Metallic Tartrarsenites, 311

I'.wing ( Prof. J. A., F.R.S.), the Steam Engine and other Heat
Engines, 219

l'.\-.Meriilian Altitudes, Corrections of Maximum and, J. White,
485

Examination Curve, the, Prof. C. Lloyd .Morgan, 617

l!x]iloration at Ruwenzori, G. F. Scott Elliot, 271. 527

1 \plosion, Dr. Duprc's Report on Compressed Oxygen Cylinder,
562

I \plosion of Gases in Glass Vessels, the. Prof. 11. B, Dixon,
F.R.S., 151

Explosions, Kitchen Boiler, R. D. Munro. 197

lOxplosions in Mines, 211

l-Aplosive Nature of the Sodium and Potassium Derivatives of
Nilroniethane, the, .\. l-".. Tutton. 328

l.xplo.sives in Mines, the U.se of Safety, 184

lAplosivcs: Coal-Dust an Explosive -Agent, as shown by an
lOxamination of the Camerton Explosion, Donald M. D. Stuart,
268

1 .diry (Ch.), P.issa^'e of Light acro,s Thin Plate in Case .'.f Total

Reflection, 407
Fabry (M. Louis), a New Form of Zenith Telescope, 564
I'arm X'eriiiin, Heliiful and Harmful, 174

Falty Acids, New Compounds of Hydrazine with, A. E. Tutton,

S16
Fauna of British India, the, including Ceylon and Burma.

Moths, W. F. Kirby, 605
Faye(Herve), Presentation to. 36
Faye (H.), the New Capital of Brazil, 599
Feigning of Death in Snakes, the, R. Harry Vincent, 223
F'emow (Prof. B. E.), the Battle of the Forests, 116, 139
Ferryman (Capt.), the Da:mme \and Glacial Lake, 130
Fertilisation of I.oraiilhiis kratissianiis and /.. lin^ei, the,

Maurice S. Evans, 235
Fery (Ch. ), Gratings used in Photogravure, 576
Fewkes (J. W.), the New Fire Ceremony among the Tusayaii

Indians, 515
I'iguier (Louis), Death and Obituary Notice of. 82
Filters, Water, Relative Efficiency of, Surgeon-Major lohnston,

38
I- inger and Toe Disease, the, George Massee, 453
Finger-Print Method, Kumagusu Minakata, 274 ; the .\ntiquity

of the, Kumagusu Minakata, 199
Finger-prints, Sir W. J. Herschel, Bart., 77
I'innegan (J. W.), the .Artificial Spectrum Top, B. Moore, 292
Fire Ceremony, the New, among the Tusayan Indians, J. W.

Fewkes, 515
Fisher (Prof. W'.R.), Te.\t-book of the Diseases of Trees, Prof.

R. Hartig, 28 ; Stati.stical Account of French Forests, M.

DauViree, 64 : Forestry in Natal, 234
Fisheries: the Trawling Ouestion, Prof. Mcintosh, 115: Scien-
tific Investigations of Scottish Fishery Board, 115
Fitch ( R. ), Death of, 587
F'itzgerald (Prof. i',. F. , F. R.S.), the Kinetic Theory of Gases,

221 ; the Foundations of Dynamics, 283 ; Maxwell's Theorem

of I>jual Partition of Energy not inconsistent with Internal

Movement of Gas-Spectra, 452
Fixation in Algie, Nitrogen, Rudolf Beer, 302
Fjords, Morphology of, P. Dinse, 1 1 1
Flan-.es, Composition of ICxtinctive Atmospheres produced by.

Prof. Frank Clowes, 478
Flanimarion (M.), the Rotation of Venus, 21 ; Photographic

Determination of Position of Pole, 455
Flather (John ].), Dynamometers and the Measurement ot

Power, 30
Flight of Birds, the Wind and the. Profs. I^ngley and Curti.s,

156
Flints, the Burmese Chipped, Pliocene not Mi<Kene, Dr. W . T.

Blanford. F.R.S., 608
Floods in the West Midlands. II. Southall, 215
Fhickiger (Dr.), De.-ith of, 298
Flying, Lilienthal's Experiments in, 177
Fog Signals, Acoustic, and Navigation, .\. B. John.son, 130
Fohii Wind in the Riesengebirge, a. Dr. Ka-ssner, 451
Folgheraiter (G.), Induced Magnetism in Volcanic RcKks, 617
Folk-lore : on Chinese Beliefs about the North, 32 ; Chinese

Beliefs about Caves, 57 ; the Mandrake, Kumagusu Minakata,

608
Fonvielle (\V. de), Andre'e's North Pole Balloon Scheme, 421
Forbes (Prof. Geo. F.R.S.), the Utilisation of Niagara Falls,

205
Forbes (H. O.), a Handliook to the Primates, 242
Forcrand (M. de). Calcium Ethoxide, 263 ; Heat of Formation

of Calcium Acetylide, 552 ; Alcoholates of Linte and Baryta,

576
Forecasts, the Possibilities of Long-Range Weather, Prof.

Cleveland .Abtic, 212
Forecasts, Popular Weather, 602
Foreign Sources, Physical Society's Abstract of Physical Pa|5ers

from, 321
Forest Birds, their Haunts and Habits, Harry V. Witherby,

341

Forestry : Text-book of the Dise.-i.ses of Trees, Prof. R. Hartig,
Prof. W. R. Fisher, 28: the Planting of Timber Trees, .Alfred
W. Bennett, 33 ; Stati.stical .Account of French Forests, M.
Daubree, Prof. W. R. Fisher. 64 : the New Cypress of Nyasa-
land, 85, W. T. Thiselt.in-Dyer. F.K.S., 175: the Battle of
the Forests, Prof. B. E. Fernow, 116, 139; l-'orestryin Natal,
Prof. W. R. Fisher. 234; Forest Preservati(Hi, I'rof. C. S.
.Sargent, 3S0 ; Contraction of Trees caused by Cold, J. Clayton,
462

Forster (Dr. .A. E.), Central Euroju-an River Teuiperaturc
Variations, 83

For.ster (M. O. ), New o-Dibromocamphor Derivatives, 359

XVI

Index

May to, 1895

Kunnighily Review, Science in the, 44, 161. 450. 545

Kossil Plants of Oial Measures: ii. the Koolsof Calamilcs, Drs.

Williamson ami Scoil, 94
Fossils : Eocene Fossils at Murren, Right Hon. Sir John Liil-
bock, F. R.S. , 223 : the Mastodons of Russia, Marie Pavlova,
357 ; the Post-Pliocene Mammals of E,ist Russia, Prof. Sluc-
kenberg, 357 : the Geological Distribution of Fossils, Messrs.
Jukes- Browne, Meyer and Gregorj', 470; Pachytheca, A. C.
Seward, 480
Foster (Prof. .M., F.R.S.), Physiology for Beginners, 195 ; on
the Teaching of Physiology in Schools, 487 ; .\l!genieine
Phy.siologie, ein Gnindriss der Lehre vom Lelicn, Max \"er-
worn, 529
Foster- Melliar (Rev. .\.), the Book of the Ro.se, 362
Foucault Pendulum Exiwriment, the, (".. -A. R., 79
Foucault Pendulum at Oulilin, a, \V. R. Westropp Roberts, 510
Foucault's I'hotographic Researches, W. H. H.arrison, 299
Fowler (A.), Mira Ccti. 40: the Lick Observatory, 201 ; .-Vmeri-

can Topography, Prof. Henry llannet, 274
Fowler (W. H. ), Boiler Explosions, 345
Fowler (\V. Wardcl, Sunnner Studies of Birds and Books, 34: :

the Black-\'eined White Butterfly, 367
Fox (Howard), the Unsolved Problems of Cornish Rocks, 36
Fox (T. W.), the .Mechanism of Weaving, 149
Fraas (Erwin), the Elasticity of Solid delatine Solutions, 326
France : Statistical .Account of French Forests, M. Daubrte,
Prof. W. R. Fisher. 64 : the .Xnti-toxin Treatment of Diphtheria
in France, 83 ; the Deserts of Southern France: an Introduc.
tion to the Lime.stone and Chalk Plateaux of .Ancient .Acjui-
taine, S. Baring.Ciould, Canon Bonney. F. R.S., too; Oyster
Culture on the West Coast of France, Prof. W. A. Herdman,
F.R.S., 162: .\eronautics in France, Prof. Cornu, 299:
French .Scientific Ex|>edition to Central .\sia, 421 ; New-
Metric Scales a<lopted, 613 ; .Annual Exhibition of French
Physical Society, 613
Franchimont (M.), Ureo..-vthanol, 504
F'rancis (E. I, I^nljoratory Exercise Book for Chemical .Students,

270
Frankland (Dr. E., F.R.S.), Conditions affecting Bacterial Life

in Thames Water, 599
Frankland (Mrs. Percj), Lehrbuch der Bakteriologi.schen Un-
tersuchung imd Diagnostik, Dr. Ludwig Heim, 481 ; Mi-
crobes and .Metals, 611
Franklin (C. I..), the Normal Defect of Vi.sion in the Fovea, 615
l'ra,scr (Col. A. T. ), Cows kept in Caves by .Arabs, 325
Freezing I'oini of Dilute .Solution, ihe, |. W. Rodger, 617
Fromm (Dr.). .Aromatic Esters of .Arsenious .Acid. 616
Froude (R. E.), Bilge-keel and Steadiness in First-cla-ss Battle-
ships, 569
Fry (Rt. Hon. Sir I-:<lwar(l, F.R.,S.), What arc. Acquired

Characters? 8 ': .Act|uire<l Characters, 197
Fuchs(E. )and I,. D. I.aunay, Traite dcs Cites Mincraux el

Metallifercs, 555
Fumeaux (W". ), Bi:tterflies and Moths (British), W. F. Kirby, 339

CaUcxiid.T, Compiarative Morphology of, H. M. Bernard, 455
(iait (Akxanderi. ICIectrification ol .Air and other {;.-\ses, 495 :

the Diselectrificaiion of .Air, 573
(iaiton (Francis, F.R.S.), .Acipiired Characters, 56: Psychologic

lies (iramis Calruhteurs et [oueurs d'tchecs, .Alfre<l Binel,

73 ; a New Step in Statistical .Science, 319 ; tjue.stions bearing

fin Specific Stability, 570 : Rea.son of Failure of Calton's

Theory of Organic Evolution, Dr. .A. R. Wallace, 450
(iamble (F. W. ), Hhyiuhoiiriinii lenalris in England, '^T,
(larliasso (A.), Refraction ami Di.s|K-rsion of Rays of Electric

Force, 70
Carbon (Jules), la Pratique du Teinluricr, 604
(iardncr (Walter .M.(, la Pratique du Teinturier, |ules (iarcon,

604
(iarman (Prof. S.), the Sus|)ende<l .Animation nf Snakes, 274;

Thirst- Endurance in some Vertebrates, 343
(iarnett (A.I, Pellitorine ami Pi|M:rovaline, 310
(iarnicr (Julesi, Action "if Electric Current on Fused Metallic

Sulphates, 359
Carrigou- Lagrange (P.), New Relations lietween Barometric

MovcTncnls in Northern Hemisphere and those of Sun and

McKm in Derliniilion. 407
Carson (Dr. |. (..■. liarly British Races, 67, 90
(•aAco(I'r. hranrisco). Death iif, 35
(Ja-sc.* : the Kinetic Theory of. Edward P. Culvcrwell, 78, 581 :

Dr. J. IjiriiKir. F.R.S.. 152 : .S. ||. Hurbniv. I I^S., 175;

Prof. G. F. Fitzgerald, F.R.S., 221, Rev. IL W. Watson,
F.R.S., 222: Prof. .Arthur Schuster, F.R.S., 293: G. II.
Bryan, 31, 152, 176, 319; Prof. Boltzmanu's Letter tm the
Kinetic Theory of Gases, 5S1 ; on Certain Questions of the
Theory of Gases, Prof. Ludwig Boltzmann. 413 : the Ratiii of
the S]>ecific Heats of Gases. S. H. Burbury, F.R.S., 127 ; the
F2xplosion of tiases in Cdass Vessels, Prof. II. B. Dixon, F.R..S.,
151 ; Electric Discharge through Gases, Prof. J. J. Thom-
son, 330 ; Electrification of Air and other Ga.ses, Lord Kelvin,
I'.R.S., Magnus Maclean, .nnd .-Vlexander Gait, 495 ; on the
Liquefaction of Gases, Prof. Charles Olszewski, 245 ; Prof.
James Dewar, F.R.S., 245, 365, 413; .M. .M. Pattison Muir,
"364, 388, 436

Gaud (Fernand), the Oxidation of Acids by Fehling's Solution,
96 : the Conversion of Lactic .Acid into Propionic Acid, 144

Gatitier (M.), Superposition of Optical Eflects of Several .Asym-
metric Carbon .Atoms in same .Active Molecule, 47 ; Super-
position of Optical Eflects of different Asymmetric Carbon
.Atoms in same .Active Molecule, 168

G.iutier (H.). Lei;ons de Chimie, 459

Gawthrop (H.), Vari.-itiuns in Character of Seasons, 357

(lee (William). Short Studies in Nature Knowledge, 557

(ieikie (Sir .Archibald, F. R. S.), Twenty-five Vears of Gei>logical
Progress in Britain, 367 ; Memoir of Sir .A. C. Ramsiiy, 385

Geitel (Herr), .Action of Light in producing Electric Discharge
thrtiugh a X'acuum Tul>e, 514

Gelcich (Prof. Eugcniol, Otlica, 244

(ieo-Morphology : Lilhogenesisder Cicgcnwarl, J. Wallher, 313 ;
Gcotektonische Problenie. .A. Rothpletz, 313 ; Morphologie
der Erdoberflache, Dr. .A. I'enck, 313

Geography: .American Government Surveys, 19; the .Alaskan
Frontier Survey, 19 ; Moimt Logan and .Moimt .St. l\lias, 19 ;
the .Absorption of the North American Indian Reservations,
19 ; the .Anglo-German Frtintier Survey in East .Africa, (,'. S.
Smith, 19; Coinmercial Geography, E. C. K. Gonner, 30;
Mr. Trcvor-Battyes Visit !o Kolguof Island, 36; Dr. Doiialil-
son .Smith's Expedition to L;iUe Rudolf, 61 ; British Central
Africa Protectorate, H. H. Johnstone, 66; a pre-Columbian
Di.scovery of America, \'ule Oldham, 83 ; the Morpho-
logy of Fjords, P. Dinse, III ; Cliudiing and l-'xplora-
tion in the Karakoramllimalayas, William M:irlin Con-
way, 196 ; .American To]iography, .-V. Fowler, 274 ; Re-
turn of Mr. G. F. S. Elliot, 298; Mr. .Scott Elliot's
Exploration of Mount Ruwenzori, 271, 298, 441, 527;
Baron Toll's Siberian Expedition, 327; Peru, E. W. Midden-
liorf, 388; Relation of (Iravity to Continental Elevation. T.
C. Mendenhall. 430; Influence of Temperature on Distribu-
tion of Animals and Plants, Dr. C. II. Merriam, 441 : the
Nile, Sir Colin .Scott-Moncrieff, 444; Paris Geographical
Society's Prize .Award fur 1S95, 4S9; Death nf Sir Edward
Bunbury, 468; .Survey nf Lukchun (Tibet) Depression, M.
Koborovsky, 491; New Law of Geographical Dispersal of
Sjiecies, Chas. Dixon, 545; Ihe New Capital of Brazil, II.
I'aye, 599

(ieology: the Unsolved Problems of Cornish Rocks, llow^ird
Fox, 36; the Roots of Calamites, Drs. Williamson and Scoll,
94: Eocene Rock at Murren, Sir J. Lul)bock, 94; Recent
Sections in Malvern Hills, Prof. .A. II. (ireen. F.R..S.,94;
the Sciulh Denbighshire Scries, Philip Lake, 94 ; Geological
.Society, 94, 143, 190, 239, 357, 40O, 47S, 502, 527, 575.,599 ;
the Deserts of .Southern France, S. Baring-Goidd, Canon
Bonney, F.R.S., too: Mutual Alterations of Basaltic .Andesile
and Later Euritc, Prof. Cole, 112; the .Malta I'leisloccnc
Beds, J. H. Cooke, 143 ; the Iowa Survey, 157; Curious
Limestone Cascade I'ornialion in Iowa, 157; K'nenc at
Murren (Correction of Sir John Lubliock, p. 94), Dr. 1'.. de
Telleidierg, 180; the Iron-liearing Rocks of iMesalii Range in
Minnesota, J. E. Spurr, 182; Ihe Tarns of Lakekind, J. 1".
Marr, F. R.S., 190; Eocene Fossils at Murren, Right lion.
.Sir |ohn LubUick, F.R.,S.,223; i>n the .Age of liie I!arlh,
I'rof. John Perry, F.U.S., 224, 341, 582: Prof. Tail, 226 :
Lord Kelvin, 227. 438: I'mf. W. |. Sollas. F. U.S., 535, 558:
Dr. Bernard llobsoii. 558 : Dr. .Alfred R.Wallace. F.R.S.,
(J07 ; C. Davison, 607; Canadian (;eologic;il Survey, 236;
Lower Green .Sand of East .Surrey, T. Leightnn, 23(1; Sliuly
of Ejected Blocks from Monte Somma, Prof. Johnston. Lavis
and f)r. J. W'. (iregory, 251 ; Disproof of Organic Nature of
E071 ion. Prof. Johnston- Lavis and Dr. J. W. (iregory, 251 ;
Die Lebcnsweise der .Meeresthiere, Beobachlungen iiber das
Leben der Ge(ilogisch\\i( htigen Thiere, Prof. Johannes
Wnlther, 269; .Similarity of Bnlurbisian ami I'yrenean

Maj) 30, 1895 J

Index

XV 11

Ix-hinoitis, Dr. Noctling, 280; Lchrlnich der Pctr ..;i.i1th;.
Dr. Kcr<i:nan(l Zirkcl, 290; Lithotjcnusis der (icj^ciiwar*,
liihanncs Walther ; Gcotfktoni.scln; rrobleme, A. l<olli|>lf;z ;
.Morphologic der lirdoberflache, Dr. .Mlwrt Hcnck ; Dr. J.
\V. tlrcgory, 313 ; Origin of Alpine .Serpentines, Dr. Weins-
chenk, 326 ; Alpine Gnei.s.s and Liraniie, Dr. Weinschenk and
l*rnf. I.owl, 326 ; Lale Olacial or Chaniplain Subsidence and
Re-elevation of St. Lawrence River Basin, Warren Uphani, 333;
1 layileri .Medal awarded lo Prof. Daubree, 345 ; the Mastniiuns
of Russia, Marie Pavlova, 357 ; the Po.st- Pliocene Mammals of
ICast Russia, Prof. .Stuckenberg^ 357 ; the Formation of Oolite,
1.. B. VVethered, 357 ; Lias Ironstone round Banbur)', li. A.
Walford, 358; Geology of Anatolia, W. K. Wilkinson, 358;
Twenty-l'ive Years of Geological I'rogress in Britain, Sir
.\rchiluld Geikie, I". R.S., 367; the .\strononiical Theory of
ihe Ice Age, E. P. Culverwell, 370; Japanese .Additions to
Palceobotany, 371 ; Remains of Sponges in Phianites of Pre-
Cambrian of Brittany, L. Cayeux, 384 : -Memoir of Sir .\n<lrew
Cronibie Ramsay, Sir Archibald Gieikie, 385 ; Carrock Kell,
Alfred I larker, 406 ; Les Abimes, les caux souterraines, les .
Cavernes, les sources, la spelicologie, E. .K. Martel, Canon
T. G. Bonney, P.R.S., 410; the Fauna of the Lower Cam-
brian, Prof. VV. K. Brooks, 423 ; tdacial Phenomena < if New -
foundlniKl, Labrador, and .Souli (Ireenland, G. F. Wright,
430 : Ihetdaciationot .Mounl Ruwenzori, Scott Elliot, 441 ; the
Life and Correspondence of William Buckland, D. U., F. R.S.,
.Mrs. Gordon, 457 ; the Barrenness of Pre-Cambria'' Rocks,
Dr. C. Callaway, 462 ; the theological Distribution of Fossils,
-Messrs. Jukes-Browne, Meyer, and (Gregory, 470 ; Physical
Conditions of Mediterranean Ba.sin, Prof. E. Hull, 478;
-Superficial Deposits of .Shantung. S. B. J. .Skertchly and
T. W. King.smill, 478 ; Pachytheca, .\. C. Seward, 480 ;
.Sequence of Barbados Rocks, Dr. J. W. Gregory, 502 ; Sea
and Land, Features of Coasts and Oceans, with Special Refer-
ence to the Life of Man, Prof. N. S. Shaler, 507 : Geological
Researches in Connection with .Siberian Railway. 509 ; Geo-
logical Distribution of Brachiopoda, .\gnes Crane, 5'4!
-Appalachian Type of Folding, C. D. Walcott. 525 : Fossil
Kaun.as at .S|irmgfieUl, Missouri, Stuart Weller. 525 ; Drift
Boidders between Mohawk and .Sus<^uehanna Ri\ers, .\- P-
Brigham, 525 ; New Ossiferous Fissure in Creswell Crags,
W- L. H. Duckworth and F. E. Swainson, 527 ; Chemical
Composition of Oceanic Deposits, Prof. J. B. Harrison and
.\. J. Jukes-Browne, 527 ; Traitedes Gites .Mineraux el Metal-
liferes, E. Fuchsand L. de Launay, 555 ; Etude industrielle de.s
<;ites Mctalliferes, George Moreau, 555; -Annals of British
Geology, 1893, J. '*• Blake, 557: th.e Fossil of the Gotland
.Silurian, Prof. Lindstrcim, 563 : Fkivio-(jlacial and Inter-
Glacial Deposits in SwitzerlamI, Dr. I'rellen, 575; Death of
Prof. J. D. Dana, 587 ; Death of R. Fitch, 587 ; Comparison
of Russian and African (Karon) Permian Freshwater -Shells,
Dr. .\malitsky, 599; Collected Papers on some Controverted
l^iuestions of tieology, Joseph Ptesiwich, F. R.S., Prof. John
\V. Judd, F.R.S., 601"; Ihe Burmese Chipped Flints, Plio-
cene not Miocene, Dr. W. T. Blanford, F-R.S.,608; Niagata
and the (ireat Lakes, F- B. Taylor, 619
(;eometry : Anwemlung der Quaternionen auf die Geometrie,
Dr. P. .Molenbroek, 76; the Outlines of (Quaternions. Lieu:.-
Colonel II. W'. L. Mime, 76; Geometry in Schools, Edward
.M. I.angley, 176; an Introductory -Account of certain
.Modern Idea.s and Methods in Plane .\nalytical GeomcLry,
Charlotte .Angas .Scott, 483
German Imperial Physico-Technical Institute, Fifth Report

of, 20
Germany. Khymhodcmiis tcrrcstris in, H. Simroth. 294
Giaco.s;\' (Dr. Piero), Italian Scientific Exijedition ti> .Monte

Rosti, 57
<;ian.sanil Giantism, Dr. C. L. Dana. 381
Gibbe.-. I Prol. Lewis R.), Death of, 324
(iiberne (.Agnes), Radiant .Suns, 174
Gilbert's (Dr.), Researches on Development of School-children,

232
C;iles (Alfred), Death of, 468

tiirard (tMi.). Chemical Process for Purification of Water, 552
(lites .Mctalliferes, Elude Induslrielle dcs. George Moreau, 555
Giles Mineraux et Meialliferes, Traite (les, E. Fuchsand L. de

l,;iunav. 555
Glacial Phenomena of Newfoundland, Labrador, and South

Greenland, E. F. Wright, 430
<daciation ; a Criticism of the AstronoinicaT Theory of the Ice
-Age, ICdward P. Cidverwell, 33

(,; lacier Lake, the Dxmme, Captain Ferryman. 130

Gladstone (Dr. J. H., F.R.S.), .Argon, 3S9 ; the Metric

.System, 562
Glaister(John), Sir William Smellie and his Conteni[Xiraries, 149
Glass, -Avenlurine. H. -S- Washington, 112
lilass, Cireen, in Plant-Hou.ses, 514

Cdais, Simplified Process for Silvering. -A. and L- Lumiere, 571
Gla.s,s Vessels, the Explosion of Gases in, Prof- H- B. Dixon,

F.R.S., 151
edass-blowing : Die Bearbeitung des tllases auf dem Bla.setische,

D- Djakonow und W- Lermantoff, 580
Glazebrook (R- T., F-R-S-), -Mechanics for Colleges and

Schools : Statics. 484
Lllobe, the Use of the, in Crystallography, J- 'S . Buchanan,

F-R-S-. 184; William J. I'oiw, 223
Glow Lamps, 239, 35S
(;iubl) (P. C), Ihe Soaking of Seeds, 107
Glycogen in Blood, M. Kaufmann, 503

Goeldi ( Dr. E. -A. ), Breeding Habits of Brazilian Tree-Frogs, 407
Ciold Discovered in Isle of Man, 299

Gold Nuggets, the Structure of. Prof. Liversidge, F". R.S., 47
Cioldsmith ( E. ). \oIcanic Stalactites, 128
eloldstein ( Prof. ). Effect of Cathode Rays on Colour of Certain

Salts, 62, 406
Conner (E. C- K-), Commercial Cieography, 30
Gordon (Surgeon-General C- A-), the Island of Madeira, for the

Invalid and Naturalist. 197
Gordon (Mrs.), the Life and Corresi>ondence of William Buck-
land. D.D.. F.R..S.,457
GosslH.), the Black-veined White Butterfly. 391
liotch (Prof. Francis, F.R.S.), the Present State of Physiologica

Research, 103
Goto (Seitaro), Studies on the Ecto-parasitic Treinatodes of

Japan, 244
Giittingen Royal -Academy, 408
(Wittingen Royal Society. 96, 624
Gradient-Telemeter Level, 112

(.iranite. the ( juarry ing of, in India, Dr- II- Warth, 272
(Iraphic Statics, the Elements of, L. M- Hoskins, 7
Graphite, the Varieties of, H. Moissan, 191
(;rasset (E.). Physiological Properties of Oxalate and Cry-

-stallised Salts of Nicotine, 264
Gravitation: Dr. J. Joly, F.R.S., 57. 127.
Worthington. F.R..S., 79 : Prof. Oliver J.
Gray (Prof. A.), Les Oscillations Electriciucs, H. Poincare, 361
Green (Prof. -A. H., F.R-S.), Recent Sections in Malvern Hills,

94
Green Glass in Plant-Houses. 514
Greener (I. H-). Death of, 561

Greenhill'lProf- A- G.. F.R.S.), the .Science of Mechanics : a
Critical and Historical Ex|)osition of its Principles, Dr.
Ernest Mach, 49 : the .Alleged -AI>soluteness of -Motions of
Rot.ation, 105 : the Dynamics of a Top, 309

C'.reenland, Meteorological Station e>tabli.-hed at Angmagsahk,
279

(Iregory (Dr. \. W.), .\nalog)- belween \esuvian Block and
Arckvan Ri'xrk-masses, 251 : Lithogenesis der Gegenwart,
Johannes W'alther. 313: ( leotektonisrhe Probleme. A.
Rothpletz. 313 : Morphologic der Erilolwrtlache, Dr. Albert
Penck, 313: the (leological Distribution of Fossils, 470;
Sequence of Barbados Rocks, 502

Clr^ory (R. A.), the Planet Earth: an -Astronomical Intro-
duction to Geography, 291 ; the -Advance of Technical
Educati m. 379

tirehant (N.), CaH)on Monoxide Produced by Combustion in
Electric Arc. 622

t;riffiths (E. IL). Ca|xicity for Heat, 11: S|>ecific Heat of
-Aniline, 71 ; Laient Hea; of Eva|Kiration of Water, 334

Grodspeed (Mr-), the Sjwcific Heat of Tungsten. 424

Groom (Percy), Monocotyledonous -Saprophytes. 263

Ciross (Dr.). Electrolysis of Solution of Mixed Nit;ate ami Sul-
phate of Silver plus a liule Nitric Acid. 288

Gr.>.sse(Dr. E.), Die .Anfangc der Kuii-st. 241

Grote (Dr. Hermann), De;iih of. 4SS

C.rouse Exmlus in \orkshire, I. V.. Harling, 422

Growth of St. Louis Children, the, William Townsend Poner,
Prof. Karl Pcar.s<jn, 145

Gnison (Hermann). Death of. 344

GuglielmolSig.), Meih.xl n{ Identifying Former I^vel of Water
after Withdrawal of .Solid iniincrseil therein, 231

Guiana Forest, in the, James Rtnlway, 387

223 : Prof. A.
Lodge. F.R.S.,

M.
'54

xvni

hide.

tSuJp!:-iiicnt to Natvt-
May ;o, iSgs

w,..i,,:..i.. il.con), the Centrospheres of Tlant-Nuclci, 113

fiuns, the Measurement of Pressures in, Kcv. K. Bashforth, 461

Guntz (M.), Simple Demonstration of Presence of Argon in
Atmospheric Nitrogen, 599

Guppy (Dr. H. B. ), MethiKl of Determining Influence of Springs
on River-Temperature, 1 19

Gumey (J. H.), Catalogtie of the Birds of Prey (Accipitres and
Striges), 552

Guy (Arthur F. ), Electric Light and Power, 30

Guye (P. A.). Su]ierposition of Optical Effects of several
Asymmetric Carbon Atoms in same Active Molecule, 47 : the
Ethereal Salts derived from Active Amyl Alcohol, 144 ;
Supeqiosition of Optical Effects of Different Asymmetric
Carbon Atoms in same Active Molecule, 168; Optical Reso-
lution of a-Oxybutyric .\cid, 503

Gylden (Prof. Hugo), the Mean Parallax of Stars, 21

Haacke (Dr. Wilhelm) Die Schiipfung der Tierwclt, 149
Hada (S. ), Hypophosphites of .Mercury and Bismuth, 359 .
Haddon (Prof. .\. C.), Die .\nfange der Kunst, Dr. E. Grcxsse,

241
Hadow (G. E. ), Snakes, " Playing 'Possum," 127
Hager (T. ), .■\cidimelry of Hydrt^en Fluoride, 430
Hagenbach (.\ugust). Thermo-couples of Melals and Saline

Solutions, 70
Hailsiones, Enormous, Ci. J. S}'mons, 24
Hailstones of Switzerland, "1883-93, Dr. C. Hess, 230
Hainlen (Dr.), the Pri>ix;rtics of Liquid Ethane and Propane, 65
Haldane (Dr. John). Black Damp, 477

Hale (I>r. \Vm. H.), the .American -Vssociation, 390; the Re-
cent Storm in the United States, 417
Hallcr (.X. ), Ehullioscopic Study of Colouring Matters from

Triphcnylmelhane, 455
Hamilton (D. J.), a Texl-liook of Patholog)', 148
Hanitsch (Dr. R.), .\merican Fresh-water S|X)ngcs in Ireland,

5"
llann (Dr. J.), Ramfall of Sandwich Islands, 500

Hanling (C), the (iale of December 21-22, 1894, 311

Har<l»ick (H. J.). .Alpine Climates for Consumption, 54

Hardy (E.), -Application of Sound-Vibrations to Analysis of

Two Gases of Different Densities, 407
Hare, the -Arctic, in Iceland, 614
Harkcr (Alfred), Carrock Fell, 406

Harker (Prof. .Allen), Death ami Obituary Notice of, 2c6
Harmonic .Analyser, a .Simple Form of, (i. U. Vule, 501
Harrison (Prof. I . B. ), Chemical Composition of Oceanic De-
posits, 527
Harrison (\V. H.), F'oucault's and Bayard's Photographic

Researches, 299
Han (J. H.), Peripatus in the West Indian Islands, 511
Hartig (Prof. R.), Text-lxx>k of the Disea.ses of Trees, Prof. W.

R. Fisher, 29
Haning (J. E.), .Attitudes adopted by Birds for Concealment,
181 ; Inva.sion of North and Norlh-East Coasts by Little Auk,
422 : ( Irousc Exodus in Yorkshire, 422

Hartwig (Dr. E. ), a New Variable Star of the .Algol Tyjie. 64

arvar<l College
H Pickering, 329

arvaril College 01»servatory, Recent Work at

:ol lyiK
, Prof.

E. C.

Harvard College by an Oxonian, fleorge Birklieck Hill, 386
Harvie-Brown (I. ,A. ), the Slarling in Scotland, 280
Haushofer (Prof, von). Death of, 278
Havilanil (Dr.), New S|)ecies of Termites found by, 575
Hawaiian lOands, Disturbances in Direction of Plumb-line in,

E. I). Prcsion, 619
Hawkins (Dr. F. B., F.R.S.), Death of, 180
Haworlh (E. ), Synthesis of omelhylbiityri>lactonc, 526
Hay(Dr. CJeo.), New .Methrxl of Correcting Course.s at Sea, 215
Hay (RoI)erts), Watcr-I'ower applied by Electricity to Gold-
dredging, 470
Haycrofi (H. C), Student's .Apparatus for Determining Mechan-
ical hVpiivalenl of Heal, 239
Hayter (H. H.), Death of, 513
I lay ward (Jane Mary), Bird Notes, 532
Maxcn (Prof. H. A.), Sunsixits and •Aiiror.x';, 46 ; Balloon

AMTcnt by J. A. .Andree, 325 ; the M<Min and Rainfall, 451
Heat, Capacily for, E. H. Griffiths, II
Ileal of Water, Delcrminalion in Electrical Units, of S|x:cific,

Prof. A. Schuyler, F.R.S., and W. (iannon. 214
Heal,. Student's Apparatus for Determining Mechanical Equiva-
lent of, Prof. W. E. .Ayrl<in an<l H. C. Ilaycraft, 239

lloi Engines, the Steam Engine and other. Prof. J. A. Ewing,

F.R.S., 219
Heath (Grace), Science Teaching in Schools, 56
Heaviside (Oliver, F.R.S), Electromagnetic Theory, J. Swin-
burne, 171
Heidenreich (Herr), Carlxizide and Di-urea, 39
Heim (Dr. Luilwig), Lehrlnich der Bakleriologischen Unler-

svichung und Diagnostik, Mrs. Percy Fninklaml, 481
Helical Gears. .\ Foreman I'auern Maker, 30
Heliotropism, Dr. W. Rothert, 84
Helium, Terrestrial, 512 ; Prof. Ramsay, 543 ; W. Crookes,

F.R.S. , 543 : J. Norman Lockyer, C.B., F.R.S., 586
Hellmann (I'rof. G.), ihe Invention of the Barometer, 422;

Wind Velocity at Berlin, 491, 623 ; Die alteslen Karlen det

Isogonen, Isoclinen, Isodynanien, 509
Helm (Dr. G.), Grundziige ilir Malhematischen Chemie. 580
Helmholtz (Hermann von), the Physical Work of. Prof. A. W.

Riicker, F.R.S., 44, 472, 493 ; Pro|X>scd Monument to, 613
Henderson (G. G,), Metallic Tarlratsenitcs, 311
Henderson (J.), Electrolysis of Potassium .Allo-I^lhylic Cam-

phorate, 621
Hcndorff (Capt.), Flying Copeiwds, 300
Henrici (O. I, .Science Teaching in .Schools, 106
Henry (Charles), Influence of Rhythm of Successions of Inter-
ruptions on .Sensitiveness to Light, 336 ; Effect of Rhythm on

\'isibility of Signals, 588
Henry (Louis), Methylene I.aclale, 620
Herculis, the \ ariable Star Z, 616
Herdnian (Prof. W. .A., F.R.S.), Drift Bottles in the Irish -Sea,

151 ; Oyster Culture on the West Co.asl of France, 162 ; Ihe

Port Erin Marine Biological Station, 281
Heredity: .Acquired Characters, Rt. Hon. Sir Edw. Fry,

F.R.S., 8, 197; Prof. E. Ray Lankester, F.R.S., 54, 102,

245: Prof. Edward B. Poulton, F.R.S., 55, 126: Francis

Gallon, F.R.S., 56; J. T. Cunningham, 126, 293: John

CIcland, 294
Hermaphroditism in Mollusca, Dr, Paul Pelseneer, 213
Hcrschel (Prof. .A. S., F.R.S.), Aurora of November 23, 1894,

246 : the Aurora of Novemlur 23, 1894, 390
Hcrschel (Sir W. J., Bart.), Finger Prints, 77
Hertwig (Prof. Dr. O.scar), Zeit- und Streitfragen der Biok^ie,

265 ;

Hertz, the Foundations of Dynamics, Prof. G. 1'. litzgeralil,
F.R.S., j83

Hertz (.A.), Potential Gradient in Positive Portion of (dow
Discharge, 406

llesper and Phosphor, Kuniiigusu Min.ak.ata, 417

Hess (Dr. C), Swiss Mailsiorms, 1883-93, 230

Hewitt (C. J.), .Manufacture of Standard Screws for .Machine-
made Watches, 22

Hewitt (J. T. ), Elemenlary Practical Chemisliy, Inorganic and
Organic, 364

Hill (l.eorgc Birkbeck), Harvard College by an Oxonian, 386'

Hill (J. P. (, New Species of F.nleropneusia from New South
Wales, 264 ; Platypus I'.mbryo from Intrauterine Egg, 264

Hill (Prof. Leonard), Influence of Force of Gravity on Circula-
tion, 238

llime (Lieut. -Colonel 11. W. L.), Outlines of Quaternioas,
154 : the Elements of (Jualerniims, 20I

llimstedt (F. ), a New Determination of the Ohm, 571

Mind (Dr.), Cornel 1S94 I. (Denning and Brorsen's Comet),
302

Historical Epidemiology, 579

History, Ihe Beginnings of, G. Mas|X'ro, 122

History as a Science, Prof. Prolhero, 162

History, .Science and, .\lfred H. lluth, 176

Hobson (Dr. Bernard), the .Age of Ihe Earth, 55S

Hodgkins Prizes, Ihe, Prof. S. P. l^ngley, 292

Hocrnes(Dr.), Prehistoric Objects in^North-east Italian Museums,

'57 " ...

Hoilseina (Dr.), Behaviour of Hydrogen to Palladium al \ arious

Tem|X.'ratures and Pres.Nures, 624
Holtzapftel (J. J.), Applications of Ihe .SamlBlast, 588
Homing of Lim|>els, the. Prof. C. Lloyd Morgan, 127
Homogeneity of Structure the Source of Crystal Symmetry,

Wm. Rarlow, 58: II. A. Miers, 79
Honduras, the Earlhcjuake of November 1894 in, J. Crawford,

280
Hong Kong and Jamaica, Caterpillar Tree Plagues in, 231
Hopkins (F. G.), Pigments of Pierida-, 142
Hopkins (William J.), Preparatory Physics, 436

S:ipptemcHt to S'atitri^'^
May 30, 189s J

Index

xi\

I lorn Expedition to Central Australia, the, Prof. Baldwin

Spencer, 222

llDrse, the, I'rof. N. S. Shaler, 44

Horse Breeding for Farmers, Alfred E. Pease, 435

Horticulture: Royal Horticultural Society, 281 ; the Book of the
Kosf, Rev. A. Foster-Melliar, 362 ; the Origin of the Culti-
vated Cineraria, \V. Bateson, F. K.S., 605

Hoskins (I.. M.), the Elements of Ciraphic S:atics, 7

Howard (L. 1'.), Entomology in America, 490

llubrecht (I'rof.), Origin of the .\ninion, 624

Hughes (I'rof. D. E., F'.R.S.), the Early History of Telephony,

541
Hughes (Oeorge), the Construction of the Modern Locomotive,

N. J. Lockyer, 97
llulke (John Whitaker, F. R.S.), Death and Obituary Notice

of. 392
Hull (I'rof E., F.R.S.), Physical Conditions of Mediterranean

Basin, 478
Human Species, the Varieties of the. Prof. Guiseppe Sergi,

595 , . ,

I lungary. Earthquake in, 200
lluni (H. A.), Southerly Bursters, 230
Hurricane Signal, New, 344

Hurst (Dr. C. Herbert), a True Spectrum Top and a Comple-
mentary One, 510
lluth (.'Mfred H.), .Science and History, 176
Ihitton (.\rthur Wollaston), the Vaccination (Juestior, 149
Huxley (Right Hon. T. H., F.R.S.), Past and Present, i ; the
Life of Sir Richard Owen, 169; Pal.xontology at the Royal
School 01 Mines, 223
Hyde (Ida H.), the Developmental History of Medusae, 231
I lydrazine, an Inorganic Mode of Preparing, Dr. Duden, 301
I lydrazine, New Compounds of, with Fatty .'Voids, A. E. Tutton,

Hydrazine N.^Hj, Isolation of Free, M. Lobry de Bruyn, A. E.

Tutton, 544
Hydrocarbons, the Commercial Synthesis of Illuminating, Prof

X'ivian B. Lewes, 303
Hydrogen, Determination of Critical Temperature and Boiling

Point of. Prof Olszewski, 488
Hydrogen, Phosphoretted, a New ^^ethod of Preparing, Prof.

Retgers, 23
Hydrography, Critical Revision of Estimates of .'\verage Ocean

Depth, Dr. Karstens, III : the Relative Densities, &c., of

Atlantic and Mediterranean Waters, J. V. Buchanan, 468;

C'ruise of I\'ayczdiiikm .\rctic Ocean, N. Knipovitch, 500
Hydrostatics, an Elementary Text-book of, VV. Briggs and O.

H. Bryan, 509
Hygiene: a Treatise on Hygiene and Public Health, Thomas

Stevenson and Shirley V. .\lur|ihy, 124; the Disinfection of

Fiecal Matter by Copper .Sulphate, H. Vincent, 168 ; Air,

Water, and Disinfectants, C. .Nl. .Vikman, 412
Hygrometer, a New, Dr. Verschaffelt, 167

Ice Age, a Criticism of the .Vstronomical Theory of the, Edward

P. Cidverwcll, 33; E. P. Culverwell, 371
Irthyology : the .^chromatic Spindle in Spermatocytes of
Elasmobranch F'ishes, J. E. S. Moore, 140 ; Studies on the
Ecto|)arasitic Treumtodes of Japan, Scitaro (loio, 244 ; Nf w
Species of F^nteropneusta from New .South Wales, J. P. Hill,
264 ; Gases of Swimming Bladder of Fishes, Jules Richard,
576
Identification : Finger-Prints, Sir W. J. Ilcrschel, Bart, 77 ; the
.•\ntiquity of the P'inger-Print .Method, Kumagusu Minakata,
199, 274
Illinois River, Biological Work on the, 593
Illiiminaling Hydrocarbons, the Commerciiil Synthesis of, I'rof.

Vivian B. Lewes, 303
ln;-e (W. IL), .\dipic .Acid and Derivatives, 311
Index : Kewensis Plantarum Phanerogamarum, Sumptibus Beati
Caroli Roberti Darwin dudu tl consilio, Josephine D.
Hooker, confecit B. Daydon J.ickson, F.-usciculus iii. , 54
India : Dr. Watt"s Dictionarv ol ihe Economic Products of
India. 4: W. T. Thiselton-I)yer, F.R.S., 150: Dr. V. Ball,
F.R.S., 150: Rcise nach Sudindien, Emil Schmidt, lOl ; the
<^)uarrying of Granite in India, Dr. W. II. Warlh, 272; the
Fauna of British Inilia, including Ceylon anil Burma Moths,
W. F. Kirby, 605
Indian (North .\nicrican) Reservations, the .Absorption of the,
19

Indian Islands, West, Peripatus in the, J. H. Hart, 511
Iniliana University, a Biological Station to l)e Established en a

North Indiana Lake, 422
Indo-Malayan Spiders, Thos. and M. E. Workman, R. I.

Pocock, 99 ; B. A. Muirhead, 153
Infra-Red Sijectrum, on Recent Researches in the. Prof. S. P.

Langley, 12
Ink-Crystals, 60

Instinctive .Attitudes, S. S. Buckman, 31
Institution of Civil Engineers : Annual Banquet, 538
Institution of Mechanical Engineers, 22, 377
Institution of Naval .Architects, 568
Intercolonial .Astronomy and Meteorology, 278
Intern,itionales -Archiv fiir Ethnographie, 525, 573
Invention, the Origins of, Otis T. NIas<m, 557
Involution and Evolution according to the Philosophy of Cycles,

125
Ireland, American Fresh-water Sponges in. Dr. R. Hanitsch,

5"
Ireland, the .Arctic Hare in, 614

Iridium, .Magnetic Properties of, S. H. Uracketl, 158

Irish Sea, Drift-Botlles in the. Prof. W. .A. Herdman, F'.R.S.,

■5"
Iron, Slow Changes in M.agnetic Permeability of, W. M.

Mordey, 526
Irvine (Robert), Dr. John Murray and. Chemical Changes l>e-

twcen Sea- Water and Oceanic Deiwsits, 304
Isle of Man, Gold discovered in. 299
Isolation of Free Hydrazine N.I I,, >L Lobr)- de Bruyn, A. E.

Tutton, 544
Italian Scientific Expedition to Monte Rosa. Dr. Piero Giacosa,

57
Italy, Earthquake in, 110, 513, 5S7

Jamaica, Hullelin of the Botanical DeiKirtment, 412

lamaica and Hone; Kong, Caterpillar Tree-Plagues in, 231

jan.s.sen (Dr.), Novel Methods in Photometry, 395

Janssen (J.), this Winter's .Minimum Temiwratures on Mont

Blanc, 622
Japan : Butterflies fro3ii China, Jajian. and Corea, John Ileruy

Leech, 6 ; Studies on the Ectoparasitic Trematmles of Ja|>an,

Seitaro Goto, 244 ; Japanese .Additions to I'alieolxjtany, 371 :

Destruction of the Seismological Observatory at Tokio, Prof.

J. W. Judd, F.R.S., 533
Japp (F. R.), Condensation of Benzil into FUhyl Malonate, 143
Jaumann (G.), the Process of Light Emission, 334
Joachim (Dr. G.), Effect of Suspension of Heat on Circulation,

288
Johnson {.A. B.). .Acoustic Fog Signals and Navigation, 130
Johnson (Charles, W. L.), Pseudo-Satellites of Jupiter in the

Seventeenth Century, 285
Johnston (Surgeon-.Major), Relative Efficiency of Water- Filters,

Johnston-Lavis (Prof), Study of ICjecled Blocks from Monle
.Somma, 251

Johnstone (H. H.). Briti.sh Central .Africa Protectorate, 66

Johnstrup (I'rof F. I, Death of. 229

Joly (Dr. J., F.R.S.), Gravitation, 57, 127, 223; the .Ascent of
Sap, 93

Jones (Dr. L. C), an Observation on Moths, 79; More alMut
Moths, 321 : a Snake " PKaying "Pos-sum," 107

Jonquieres (M. de), Demonstration of a Theorem of Whole
Numbers, 503

Jordan (Ch.) Optical Resolution of a-Oxybutyric .Acid. 503

journal of the .Academy of Natural Sciences of Philadelphia. :6

journal of .Anatomy and Physiology, 93

journal of .-Vsiatic Swicty of Bengal, 500

journal of Botany, 23, 430

"journal of Rus.sian Chemical and Physical Society, 452

jowett (H. .A. I).), .Aconitine .Aurichlorides, 430

JikUI (I'rof J. W., F.R.S. ). Ma>sive Minends from Inilia and
.Australia, 431 : Destruction of the Seismological Observatory
at Tokio, Jai>an, 533 : Collected Pajwrson some Controverted
(Questions of Geology, Joseph Pre.stwich. F. R.S., 601

Jukes-Browne (.A. J.), the Geological Distribution of F'ossils,
470; Chemical Ciimpisiti.m of Oceanic l)e(x).sits, 527

Jungfleisch (Iv), /3-Oxycinchonine. 264; Cinchonigine, 407

Jupiter: W. F. Denning, 227: Recent Observations of. Prof.
E. v.. Barnard, 85; Pseudo-Satellites of Jupiter in- the Seven-
teenth Centur)-, Chas. W. L. John.son, 285

X \

Indc:

•X

r Sii^pUinenl to Xaru *v
t_ A fay 30, 1895

KaiscT (K.I, l'henomi;r.ii connecuii with Mingling of Lujuid
Masses, 15S

Ivanthack (A. .\.)> H. D. RoUeston, and Manual of I'racacal
Morbid Anatomy, 318

JCarakorani-Himalayas, Climbing and txploraiion in the,
William Martin Conway, 196

Karatens (Dr.), Critical Revision of Estimate of Average Ocean
Depth , III

Karten, Die Altesten, der Ist^onen, Isoclinen, I.-imiynamen.
I'rof. Dr. G. Hellmann, 509

Kasener (Dr.), a '"F'ohn'" Wind in the Uiescngebirge, 431;
Cloud-Waves, 72

Ivater's Invariable Pendulum, Obser\-alions with, IC. K. J.
Love, 516

K.aufmann (M.), Influence of Nervous System on (."ilucose
Konnation and Mismlysis, 360: (llycogen in HIockI, 503

Keiser (Prof.), New MethiKi of Pre])aring L'n.'iitur.iteii Hydro-
carlj3n AUylenc, 471

Ivellas (.\. .\l.). Argon not in Vegetable or .\nimal Substances,
620

Kelvin (Lord, P.R.S.), the Age of the Earth, 227, 43S ; Electri-
fication of Air and other Oases, 495; the Diseleclrification of
Air, 573

Kennedy (Claudius), a Pew Ch.ipters in Astronomy, 4S4

Kennedy ( W. I, the .Suspende<l Animation of SnaUes, 274

Kerr's Magneto-Optic Phenomenon, C. H. Wind, 4S

Kerr's Phenomenon, C, II, Wind, 168

Kew Gardens, Addition to, 488

Ivewensia Plantarum Phanerogamarum Index. .Sumptibus Beati
Caroli Roberti Darwin tluctu ct consilio Josephi I). Hooker
ronfecit B, Daydon Jackson, Fasciculus iii., 54

Kieff University, Bacteriological Institute to Iw Established
.at, 206

Kinch's ( Prof. ), Oat-growing Experiments, 206

Kinetic Theorj- of Gases, the, G, H. Bryan, 31, 152, 176, 319;
Edward P, Culverwell, 78; Dr, J, I^armor, K.R.S., 152:
S. H, Burbur>', I'.K.S.. 175 ; Prof G, K. Fitzgerald, K.R.S.,
221: Rev. H. W. Watson, f'.R.S.. 222: Prof Arthur
Schuster, F.R.S., 293: Prof. Boltzniann's Letter on the,
Edward P. Culverwell, 581 : Prof. I.mlwig Boltzmatui, 581

King (Prof. F. H.), the \ariations in Level of Well-Water, 62

Kingsinill (T, W,), Superficial Deposits of -Shantung, 478

Kipping (F. S.), Broniocamphoric Acid, 455: Dimethylketo-
hexamethylcne, 526 : Melting Points of Kaceniic .Modifica-
tions and Optically .Active Isomeridcs, 526

Kirby (W. F. ), the Warble Fly, 154; the Bird-Winged Butler-
flies of the E.ast, 254: Butterflies and .Moths (British), 339;
the Fauna of British India, including Ceylon and Burma,
" Moths," 605

Kirkman (Rev. T, P,), Death of, 392

Kitchen Boiler Explosions, K. D. Munro, 197

Klemcncic (Ignaz), Magneti.salion of Iron and Nickel Wires by
Rapid Electric Oscillations, 190

Knipnvitch (N.), Cruise oi XayezJiiil! in .Arctic f)cean, 500

Kiiiitilauch (O. ), Fluorescence of Solutions, 406

Kurhlin's Wind-Measurement Ex[x;rimenls at l.ifli'l Tower,
Max dc Nansouly, 181

Kiiltzow (.\. ). a Siniplifieil I'honograph, 588

Kunig (Arthur), a New .Spectrum Photometer, 334

Konia (Desire), Thernincheinical Carbon Batteries, 5^8; a
Therni'Krhcniical Carbon Cell, 541

K'lwalsUi (J. cle), Pro<lurtion of Cathode R.iys, 312; Conditions
nece?v»ar) |r) I'roiluclion of Calhcxle l<.ays, 394

KtTnner ( Prof ). Ix>randite, 392

Kret.schmar (Dr.), Death of, c8

Kroncckcr (H,), Mountain .Sickness, 394

KrtiM (Dr. Gerhard), Death of, 392

Kryrjene I^lxjralory, the I,eyden, Prol. kanicrlnigh Onnes,

Kuhlmann(W, M. F.), New Contrivance for Reailing Position of

Pointer in Sensitive Balances, 540
Kiil|)C (f>sw.-ilil), Grundrisii der Psychologic, 173
KOI/. (Dr. E.), Death <if. 324
Kunst, Die .\nfan,-;e der. Dr. E. Gros.se, Prof. .\. C, lladdon,

241

I.i Gryc (M. B3ii(|uct dc), the Moon and .Atmospheric Waves,

S16
1j Kivcd.ucicn dc), Sluily of System of Two Pendulums joined

by Elastic Thread, 232

L;ibora!ory Exercise Book for Chemical Students, E. Francis,
270

Laboratory .Manual, a. Dr. W. R. Orndorflt, 77

Ladd ((.leorge Trumbull), Primer of Psychology, 173

Lafon (Ph.), Modifications of Blood by Thermal Treatment with
Bourboule 'A'ater, 432

Lagrange (Ch.), Is Declination indicated by Comjiass, indepen-
dent of its Magnetic Moment ? 477 ; -Astronomical Co-
ortlinates referred to Astronomical and Geographical Poles
respectively Compared. 620

Lake (Philip), the South Denliighshire Rock Series, 94

Lake, the D.vmnie \'and Glacier, Capt. Perryman, 130

Lake Biological Station to be Established in Northern Indiana,
422

Lake Derravaragh, .Seiches in, J. H. R. MacFarlane, 502

Lake-Dwelling Research, Dr. Slunro, 621

Lakeland, the Tarns of, J. E. Marr, F. K.S., 190

Lakes of Daui)hine, the, .A. I)clel)eci|ue, 35

.Lamp (Dr. E.), Comet 1894 1. (Oeiniing) and Brorsen's
Comet, 302

Landerer (J. I.), a Passage of Shadow of lupiter's Fourth
Satellite, 384

Lanilolt (Herr), Method of obtaining Light of Different Wave-
lengths in Polarimetric Work, 37

Lang (.Arnold), Lehrbuch der \'ergleichenden Anatomic, 2S9

Lange (Sir D. -A.), Death of, 35

Langley (Edward M.), Geometry in Schools, 176

Langley(Prof S. P.), on Recent Researches in the Infra-Red
Spectrum, 12 ; the Wind and Birds' Flight, 156 : the Hodgkins
Prizes, 292

Lankester (I'rof E. Ray, F.R.S.), .Accjuirod Characters,
54, 102: the Term ".Acquired Char.icters, " 245; Lehrbuch
der \'erglcichendcn .Anatomic, -Arnold Lang, 2S9

Lapworth (.A.), Studies in Isomeric Change, 620

Larch Trees at Dunkeld. Original, 1 1 1

Larkin (Mr. H.), Elliptical Orbits, 234

Larmor (Dr. J., F.R.S.), the Kinetic Theory of Gases, 152;
Electrical \'ibrations in Condensing Systems, 263

Latitude, the Variation of, 373

Launay(L. de). E. Fuchs and, Traite des Gites Mineraux et
Metallifcres, 555

Laurie (.A. P.), Electromotive Force of Iodine Cell, 454

Lauth (Dr. F. ),), Death of, 421

I-awrcnce (G. N.), Death of, 488

Laws and Andrewes (.Messrs.), the Ilarndessness of Sewer .Air,

37 «

Lea (M. C. ), New Methods of Obtaining Platinochloridcs, 93
Lean (B, ), Ilomologues of ButanetetracarlHixylic Adipic

.Acids, 143
Lebret(.A.), Variation of Hall Effect in Bismuth with Tempera-
ture, 504
Lecher (E.), Experiment to test Movement of Lines of Force of

Rotating Mitgnet, 84: Unipolar Iniluction, 406
Lee (J. B. ), Instrument for Surveying by .Aid of Photography,

191
Leech (John Henry), Butterflies from China, Japan, .and

Corea, 6
Leeward Islands, the Department of Agriculture in the, 613
Leger (E.), fl-Oxycinchonine, 264 : Cinchonigine, 407
Lcighton (T. ), Lower Greensand of lOasl .Surrey, 239
Lens Work for .Amateurs, Henry Orford, 318
Lent (Dr.), Death of, [8
Leonard (Dr. C. I..), Photomicrographic Method of .Slu<lying

Cell-Motion, 541
Lepierre (Charles), the Chromates of Iron, 240
Lepinay (I. -M. de). Determination of Mass of Cubic Decimetre

of Distilled Water at 4", 599
Lepine (R. ), the Production of the Glycolitic Ferment, 336
LcrmantolT (W.), Die BearlK-itung des Glases auf dem Blase-

tische, 5S0
Lescceur (H.), the so-called Org.anic Chlorine of the G.aslric

Juice, 144
Lesse|>s (Ferdinaml dc). Obituary Notice of, 155
Level, Gradient -Telemeter, 112

Livy (.A. M.), Refraction in Polychroic Aureoles, 384
Lcvy-Dorn (Dr.), Effect of Temperature on Secretion of .Sweat,

192
Lewes (Prof \ivian B. ), the Commenial Synthesis of Illuminal-

ing Hydrocarbons, 303; Action of Heal on Ethylene, H.,

526; Cause of Luminosity in Flames of Hydrocarbon Gase.s,

526

Supplement to A'*2///r<-,*l
May ;o, 1895 J

Index

XXI

Lcwin (Prof. L.), the Peyoll Cactus Alkaloid, 288

Lewis (J. ), Stellar Parallaxes, 589

Lcyden Kryogene Laboratory, tlie. Prof. Kamerlinfjh Onnes,

408
Libraries, Public, in America, 514
Lick Observatory, the, A. Kowler, 201
Liebreich (Prof.), Propyl .Mcohol as a Separator of Cholesterin

Skin-Kats into High and Low Melting-Points, 623
Liechtenstein (Herr von), Method of Turning True Spheres,

491
Lighting : the Commercial .Synthesis of Illuminating Hydro-
carbons, Prof. Vivian B. Lewes, 303
Lightning, Increase of Damage by, Prof, von Bczold, 20
Lilienthals Experiments in Klying, 177
Limpets, the Habits of. Prof |. R. .\insivorth Davis, 511
Limpets, the Homing of. Prof C. Lloyd Morgan, 127
Lindstriim (Prof), the Kossils of the Holland Silurian, 563
Linebarger (C. E. ), Solutions of Salts in Organic Liijuids, 334
Ling {.\. K.), Action of Diastase on .Starch, 359
Linnean Society, 94, 143, 214, 263, 359, 455, 479. 527. 575
Lippmann ((I.), Photographic .Measurement of Time in Astro-
nomy, 455
Lip])manns Method, Colour I'hotographs by. Dr. Neuhaiis, 503
Licjucfactiipn of Oa-ses, on the. Prof Charles Ol.szewski, 245;

Prof [ames Dewar. 1". R.S., 245, 365, 413 ; M. .M. Pattison

Muir, 364, 388, 436
■.i(|uefaction and Solidification of Argon, the. Dr. K. Olszewski,

355
Liquids holding Solids in Solution, Critical Point of, Kaoul

Piclet, 31 1
l.iquids, .Measurement of Latent Heat of Vapori.salion of

\'arious Organic, Prof Ramsay and .Miss Dorothy Marshall,

30?
Liquids, Use of Critical Temperature for Recognition of Purity

of, Raoul Pictet, 288
i.i^ter (.'Arthur), a Monograph of the .Mycetozoa ; being a

Descriptive Catalogue of the .Species in the British .Museum,

603
Littleton (V. T. |, Molecular Change in .Silver .\malgam, 430
Liveing (Prof G. 1)., K. R.S.), Benham's Artificial Spectrum

Top, 167, 200
Liversidge (Prof, F.R..S. I, the Structure of Gold Niiggets, 47
i.ockyer (J. Norman, C.B., F.R.S.), the Sun's Place in Nature,

374- 396. 565, 590 : Observations on Sun-Spot .Spectra, 448 :

Terrestrial Helium, 586
Lockyer (X. J.), the Construction of the Modern Locomo-
tive, (ieorge Hughes, 97
Locomotive, the Construction of the Modern, George Hughes,

N. J. Lockyer, 97
Lo<lge(Prof Oliver J., F.R.S.), Gravitation. 154; Peculiarities

of Psychical Research, 247 ; the .•\llege<I Absoluteness of

Motions of Rotation, 271 ; Electroscopes in Lecture, 320
Lfewy (.M.), Photographic Studies of Lunar Surface, 143;

-Advances in Lunar Photography, 207
Logarithms: Tableau .Mctrique de I^tgarithmes, C. Dumesnil,

3S6
Lombard (Dr.), Death of, 344

I^ndon, a True University of, Mr. Crackenlhorpe, 161
London, the Teaching University for, Dr. \V. Palmer Wynne,

297
Long- Range Weather Forecasts, the Possibilities of. Prof

Cleveland .\bhe, 212
Longevity and Death, Dr. G. J. Romanes, 381
Longitudes, .\nnuaire du Bureau des, 282
I.orandite, Prof Krenner. 392

laiilhus kraussiaiius and L. tliegci, the Fertilisation of,

Maurice S. Evans. 235
Love (.A. E. 11., F.R.S.), the .Alleged .Absoluteness of Motions

of Rotation, 105, 153, 198
I.ove(E. F. |.), Okservations with Kater's Invariable Pendulum,

516
I.ovell (Mr.), the Supposed Magnetic Fatigue, 614
!,owe Observatory, the, 21

! iwell (.\lr. Percival), Seasonal Changes on Mars, 259
Ltiwl (Dr. I, .Alpine (ineiss and Granite, 326
Lubbock ( Right Hon. .Sir J. , F.R..S.), Eocene Rock at Murren,

94 : Eocene Fo.ssils at Murren, 223
l.uuiiere (A. and L. ), .Simplified Process for -Silvering Gla.ss,

371
Lunar Formations, Origin of the, .Stanislas Meunier, 425
Lunar Photography, .-Xdvances in, .\1M. L'cwy and Puiseux, 207

Lunar River Beds and Variable Spots, i'rof A. W. Pickering,

589
Lunar Surface, Photographic Studies of, MM. Lcewy and

Puiseux, 143
Lydekker (R. ), the Royal Natural History, 197
Lynn (W. T. ), Hi.story of Encke's Comet, !08
Lyon (Prof. James), Errors arising fr<;ni Imperfect .Alignment of

Slide Lathes, 622
Lyrid Meteors, the, 564

McClelland (J. .A.), Temperature of Maximum Density of
Water and its Coefficient of Exijansion in neighlxiurhood of
this Temperature, 358

McCook (Dr. Henry C. ), .-Vmerican Spiders and their Spinning
Work, a Natural History of the Orb-Weaving Spiders of the
United St.-ites, with .special regard to their Industry ami
Habits, 505

McCrae (John), the New Iodine Ba.ses, 346

.MacDonald (Dr. .A.), .Statistics of .Sensibility to Pain, 299

Macdonald, (G. W.), a Product of Action of Nitric Oxide on
Sodium Ethylate, 143 ; .Argon not in Vegetable or Animal
Substances, 620

Macdonald (H. M.), Electrical Distribution on Two Intersecting
Spheres, 308

.MacFarlane (J. II. R.), .Seiches in Lake Derravaragh, 502

MacGillivray (D.), Tuberculosis Genn ])ossessed of Locomotive
Power, 623

Mach (Dr. Ernst), the Science of Mechanics: a Critical and
Historical Exposition of its Principles, Prof .A. G. Green-
hill, F.R..S.,49

Mcintosh (Prof), the Trawling Question, 115; the Artificial
Hatching of Marine Food-Fishes, 156

Mack (Herr K. ), Double Refraction of Electric Waves in
Wood, 423

.McLachlan (Mr., F.R.S.), Geographical Distribution of
Butterflies, 479

Maclaurin (J. S. ). Action of Aqueous Potasssium Cyanide on
Gold and Silver in Presence of Oxygen, 359

.Maclean (Magnus), Electrification of .Air and other Gases, 495 ;
the Diselectrification of .Air, 573

Maclcar (Rear-.Admiral, J. P.), the Zodi-tcal Light, 391

.Madeira, the Island of, for the Invalid and Naturalist, Suqjeon-
General C. .A. Gordon, 197

Magazines, Science in the, 44, 161, 259, 380, 450, 545

Magnetism, Kerr's Magneto-Optic Phenomenon, C. H. Wind,
48, 168 : Changes of Length produced by .Magnetisation, H.
Nagoaka, 70 : Experiment to Test Movement of Lines of
Force of Rotating Magnet, E. Lecher, 84 ; Wilde's Theory
of the Secidar Variation of Terrestrial .NIagnetism. L. A.
Bauer, 103: .SecularChangesof Terrestrial Magnetism, Dr,L. .A.
Bauer, 431, 491 ; .Mirrors of Magnetism, Prof S. P. Thomp-
son and Miles Walker, 142 : Magnetic Properties of Iridium,
S. H. Bracken. 15S : Electromagnetic Theory, Oliver Heavi-
siile, F. R..S., J. Swinburne, 171 ; Toronto Ob.servator)-, 237 ;
Absolute Value of M.agnetic Elements, January 1. 1895, T^h.
Moureaux, 2S7 ; some Early Terrestrial Magnetic Discoveries
[lertaining to England, Will Whiston, L, .A, Bauer, 295 :
Solar Magnetism in Meteorolog)', Prof F, H, Bigelow, 356 :
Influence of Low Tem|wratures on .Attractive Power of
Artificial Permanent Magnets, Kaoul Pictet, 3S4 : Experi-
ments to see if Light Kays deviated by >iagnctic Field, M.
Curie, 394 ; Magnetic Rotary Dispersion in Oxygen, Karaer-
lingh Onnes, 470 : Is Declination indicated by Com|ia.ss
independent of its Magnetic Moment ? Ch. Ijigrange, 477 ;
M.-ignetic Rotational Dispersion of Oxygen anil Nitrogen, Dr.
Siertsema, 504 : .Slow Changes in Magnetic Permeability of
Iron, W. M. Mordey, 526: Priiblems and Solutions in
Elementary Electricity and Magnetism, W. Slingo and .A.
Brookcr. 580 : the .Supposed Magnetic Fatigue, Messrs.
Cam]ibcll and Lovell, 614 ; Ratio between I^nteral Contraction
jind Longitudinal Dilatation in M,ignetiscd lion Rods, A.
Bock, 614 ; Iniluced Magnetism in Volcanic Rocks, G.
Folgheraiter, 617

Mahlke(A.), High Temperature Thermometers of |ena Glass
N'>- 59. 334

Mailfert (.Abbe), Solubility of Ozone, 168

.Malaysian Spiders, Thos. and M. E. Workman, R. I. Pooock,
99; B. A. Muirhead. 153

Mallery (Ll,-Col. Garrick), Death of Oi

•Mallcvre (.A.), Peclasc and Pectic Fermentation, 191, 312

.Mallock (W. ), Vibration of Steamers, 570

Jndix

X Supplement to .\'at;ire
L May 50, 189s

Malicios (C). Kondelels Kule for Woods and End-loaded
lieains. 622

Man, the Primc\'al Savage, Worthington C"i. Smith, Prof. VV.
Boyd Dawkins. I'.R.S., 194

Man, Sea and I^ind, Features of Coa .Is and Oceans, with .S|itfcial
Reference to the Life of, Prcf. N. S. Shaler, 507

iMandrake, the, Kumagusu Minakala, 60S

Mann {Dr. (Justave), Histological Changes inducetl in Nerve
Cells by Functional Activity, 93

M . i:iing"s (Capt.) .Vscent of .\lt. Mlanje, 44I

■ ! . ;enne (L. j, Mechanism of Respiration of Plants, 24

.'.l.Licy (M.), Movements made by Cats in order to fall on their
Feel, 47 : Photographs of a Tumbling Cat, 80

Marine Animals, the Mode of Life of, I'tof. Johannes Walther,
269

•M.irine Biology : a Flying Copepod, Dr. Ostroumoff, 20 ; I'ly-
ing Co|)epixls, Capt. Hendorff, 300 : the Marine Biological
Station, Solo»el7.k, 83 ; l)icks<jn"s I'hysical Investigations in
Faroe-Shetland Seas, 115: Fftect of Compression on Seg-
mentation of Sea-Crchin Egg, Dr. A. Craf, 157 ; Julinia,
New Antarctic Compound .\scidian, \V. T. Caiman, 213;
Mermaphroditisin in Mollusca, Dr. Paid Pelseneer, 213;
the Developmental History of Medusae. Ida H. Hyde, 231 ;
the Mo<le of Life of Marine .Animals, Prof Johannes Walther,
269; the I'ort Erin Station. Prof Herdman, 2S1 ; Effecl of
F!nvironment on Development of Echinoderni Comparative
.Morphology of Ca/eixiii/ic, H. M. Bernard, 455 : Larv.e,
II. .\l. Vernon, 454 ; Role of .Amrebccytes in .Annelids, K. C.
Racovitza, 455 : the Brtxjklyn Summer School, 537

Mirr (J. E., F. R.S. ), the Tarns of lakeland, 190

.Marriott (W. ), the Thunderstorm of January 23, 1895, 502 ; the
Fro.it of January-February 1S95, 621

Mars : Observations on, 40 ; the Polar Caps of, 64 ; .Schiaparelli
on Mars, Prof W. II. Pickering, 87: the S|)ectrum of .Mars,
J'rof. VV. W. Campbell, 1 32 ; Seasonal Changes on .Mars,
Mr. I'ercival Lowell, 259; Mars in 1894, .Signor tl. .Scliia-
|iarelli, 395 ; the -Satellites of Mars, Prof. Campbell, 443

Marsh-Feveis, Sulphur Fumigation a Remedy for, AI. d'Abbadic,
480

Marsh.all (.Arthur Milnes, F.R.S.), Biological Lectures and
.Addresses delivered by, 21 7

Marshall (Dorothy), Measurement of Latent Heats of Vaporisa-
tion of Various Organic Liquids, 309

Marshall Memorial Fund, the Milnes-, 82

.Mattel (E. .A.), les Abimes, les eaux Souterraines, les Cavernes,
Ics Sources, la S|>ela;ologie, 410

Martin (C. J.). Platypus Embryo from Intrauterine Egg, 264

Mason (Prof. O. T. ), Woman's Share in Primitive Culture, 244 ;
Copiwr-.Aealhed Objects made liy .Alioriginal Metallurgists of
America, 490; the Origins of Invention, 557

M;>->[)ero (C), the Dawn of Civilisation — Egypt and Chalda.'a,
122

Mass of the ;\slcroids, the, M. Roszel. 373

M.iwe (Ocorge), the Finger and Toe Di.sea.se, 453
■1 i.-in (O. ), a PrtKlucl of .Action of Nitric f)xide on Sodium
l.tliylate, 143

Mathematics: .American Journal of Mathematics. 46, 406;
Bulletin of .American .Mathematical Society, 46, 167, 261, 430,
S^S- 573 '• •'"-■ Connection between Binary (Juarlic and
Klli|Hic Funciion.*, Prof. E. Study, 46; Isotropic Elastic
Solids of nearly Spherical Form. C. Chree, 46 ; I Fondamenii
.Maltmatici |>er la Critica dei Risultati S|>crimenlali, Prof P.
Pizzetli, 77 : .Mathematical Society, 95, 262, 308, 478, 552,
575; .McKlel of the 27 Lines on a Cubic Surface, W. H.
Blythe, 95 ; an Elementar)- Treatise on Theoretical Me-
chanics, Alexander Ziwet, lOI ; Outlines of Quaternions,
Lieut. -Colonel II. W. L. Mime, 154: Death of Pafnulij
Tchcliilchef, 180; I(olt/mann'> Minimum Theorem, H. W.
Watson, 105 ; Edw. P. Culverwell, 105, 246 ; Boltz-
niann's Minimum Function, S. II. Burbiiry, F.R.S., 78,
320; Deilh of Prof. Slielije., 251: .Mathematical Oa/elle,
261, 573; Maswell's l-aw 1,'. Partition of Energy, (i. II.
Bryan, 262: Electrical Vibrations in Condensing .Systems;
Dr. J. Larnior, F.R.S., 263; the Alleged .Al>vilutenes.<i of
Motions of Rotation, .\. B. B.xs>el, F.R.S., 271 ; Prof Oliver
J. 1-o.lgo, F.R.S.,272: A. E. H. I^ive, F.R.S., 105, 153,
198; the F.\|unsion of Functions, E. T. Dixon, 308; lOlec-
Irical Di',triliiiiion on Two Inlersectin;; Spheres, 11, .M. .Mac-
donald, 308; Dynamics of a Top, Prof. A. C. Oreenhill,
F.R.S., 309: Death and Obituary Notice of Prof Clayley,
323; Funeral of, 344: Death of Rev. T. P. Kirkmnn, 392;

the Theory of Croups of F"inite Order, iii. and iv. , Prof W.
Burnside, F'.R.S. , 478: an Introductor)- .Account of certain
Modern Ideas and Methods in Plane Analytical Cieometry,
Charlotte .Angas Scott, 483 : Mechanics for Colleges and
-Schools: Statics, R. T. (dazebrook, F. R.S. ,484: Demon-
s-ration of a Theorem of Whole Numbeis, .\l. de Jonquieres
503; F'onctions Entieres, H. Des.aint, 503; Death of Dr. E.
D. F. Meissel, 513 ; on Mersenne's Numbers, Lieut. -Colonel
Allan Cunningham, R.E., 533; Death of Prof Ludwig
Schlafli, 538 ; Sequences of Circular Permutations, Desire
-Andre, 576 : Crundzuge der Mathematischen Chcmie, Dr. ('..
Helm, 580; Death and Obituar)- Notice of Prof. J. E.
Oliver, 587 ; the Examination Curve, Prof- C. Lloyd Morgan,
617
Mawley (E.), Phenological Observations for 1894, 502
Maxim (Hiram), F^xperiments in -Aerial Navigation, 259
Maximum and Ex-Meridian .Altitudes, Correctness of, 1. White,

485
Maxwell's Law of Partition of Enei^% C. H. Bryan, 262
M-aze (-Abl>e), First Mercury Therinomeler used by Isinael

Boulliau, 576
Mecusure, the United Stales Units of Electrical, 51S
Measurement Conversion Di.igrams, Rol)ert H. -Smi-h, 221
Measures, English Weights and, H. J. Chaney, 422
Mebius (C. A.), Clow Discharge in .Air, 620
Mechanics : Institution of Mechanical Engineers, 22, 377 ; the
Science of Mechanics, a Critical and 1 listorical Kx]n)silion of
its Principles, Dr. Ernst .\lach, Prof .A. ('•. tlreenhill, F. R.S.,
49 ; an Elementary Treatise on Theoretical Mechanics, Alex-
ander Ziwet, loi ; the Measurement of Pressures in (juns,
Rev. F". Bashforth, 461 ; Mechanics for Colleges and Schools :
Statics, K. T. Clazebrook, F.R.S., 484; an F'lemcnlary
Treatise on Theoretical Mechanics. .Alexander Ziwet, 533;
Errors arising from Imperfect .Alignment of .Slide I>;ithe, Prof
James Lyon, 622 : Rondelet's Rule for Woods and End-loaded
Beams, 'C. Maltezos, 622
Me<licine : Death of I'rof Jules Regnauld, 392 : Death of Sir
William Savory, F.R.S., 440; Death of Dr. I). II. Tuke,
440
Medley (E. A.), Tests of Clow Lamps, 239 ; (.How I^nips, 358
Medus-v, the Developmental History of, Ida 11. Hyde, 231
Meinardus (Dr. ), Sheet-Lightning, 192
Meis.sel (Dr. E. D. F.), Death of, 513

Meldola (Prof), tieographical Distribution of Butterflies, 479
Melting-Points, I'rof Victor Meyer's New Method of Determin-
ing High, A. E. Tutton, 161
Memoirs of St. Petersburg Society of Naturiilists, 500
Mendelceffl Prof), the Weight of a Litre of .Air, 452 ; on -Argon,

543

Mendenhall (T. C.)., Relation of (iravily to tontinental F.leva
lion, 430

Mental .Arithmeticians, Psychology of, and Blindfold Chess-
I'hiyers, Allred Binet, Francis dalton, F. R.S., 73

Mercury : the Transit of, 40, 85, 160, 253 : the .Apparent
Diameters of Mercury, I'rof Bernard, 373

Merriam (Dr. C. II)), Influence of Temperature on Distribution
of .Animals and Plants, 441

MerseTUie's Numbers, on, Lieut. -Colonel .Allan Cunningham, 533

Metallurgy : DispUacement of Carbon by Boron or Silicon in
F'used C.a.sl-Iron, Henri Moissan, 240 : Preparation nf Hia/^liitcs
I-'oisoiiiianls, Henri Moi.s.san, 287; Boron Steel, II- Moissan
and Ci- Charpy, 336: El.aslic Behaviour of Zinc at Difl'erenl
Temperatures, E. Zimansky, 357 : Iron and Steel at Welding
Temperatures, T- Wrightson,453 : CopperSheatherl ( Ibjecls
made by -AlHirigines of .America, Profs. Putnam and Mason,
400: Slow Changes in Magnetic Permeability of Iron, W. M.
NJordey, 526: Elementary Texl-Bookof Metallurgy, A. Hum-
boldt Sexton, 556 ; a Claim for Priority, -Alex. E. Outerbridge,
(X)8

Metals, Influence of Stress in Corrosion of, T. .Andrews, 470

Me.als : Traite des Cites Miiuraux et MitallKcres, E. Fuchs
and L. dc Uiunay, 555 ; Etude Induslrielle des (olis Metal
liferes, (leorge Moreau, 555

Metals, Microbes and, .Mrs. Percy Frankland, 611

Meteorology: the Week's Weather, 19, 61. 82, 206, 230,
*5'' 279, 324, 346, 370, 393, 421, 440: Torn.ado in
Oregon. 19; Irurease o( Damage by Lightning, Prof von
Bezold, 20: Synions's Monthly Meteoroli>gl(al Magazine, 23,
525; the Recent Drought in the .Midlands, Rev. C. T. Ryves,
23: Enormous Hailstones, (1. J. Symiuis, 24; Climatological
Table of British Ijnpire for 1893, ('.. J. Symons, 24; Then-

Su/fitemcnt to A'a/«;v,~|
May 30, J 895 J

hidex

XXIll

phrastus of Eresus on Winds and on Weather Signs. Trans-
lated by Jas. G. Wood, 25 ; Karly English Meteorological
Literature, tl. J. Symons, 38 ; Report of U.S. Weather
Kiireau for 1893. 39 ; .'\merican Meteorological Journal, 45, 142,
356, 451 ; the .Services of South America, .V L. Rotch, 45 ;
Sun-spots and .Vuroras, I'rof. H. A. Hazen, 46 ; Berlin
Meteorological Society, 72, 192, 431, 503, 623 ; Dr. Schwalbe's
Kndeavijurs to Utilise for Scientific Purposes the Curves of
Tcniperauires ohiained from the "Uranus" Pillars, 72;
Cloud-Waves, Ur. Kassner, 72 ; Central European River-
Temperature Variations, Dr. A. E. Forster, S3 ; the " Baric"
Ci)n<litiiin of the .\tmo.sphere, .-V. Ramsay, 84 ; Royal Meteoro-
loLjical Society, 119, 215, 311, 527, 621 ; .Methods of Deter-
mining Influence of Springs on River-Temperature, Dr. H. B.
(luppy, iig; the China Seas Typhoons of 1893, 130; Cyclonic
Precipitation in New England. Prof. W. Upton, I42 ; the
Barometer at .Sea, T. S. O'Leary, 142; Insignificant Sequela;
of Eorest Fires, Prof. C. .Al>be, 158; Determinations of
Absoqjtion of Solar Radiation by Fog and Cirrus Clouds,
Profs. Bartoli and Stracciati, 180; Pilot Chart of North
Atlantic for November 1894, 181 ; Koechler's Wind-Measure-
ment Experiments at Eiffel Tower, Max de Nansouty, 181 ;
the Upsala Meeting of the International Meteorological
Committee, 185 ; Inversion of Temperatures in 26'58 Day
Solar Magnetic Period, F. II. Bigelow, 190; Sheet-Lightning,
Dr. Meinardus, 192 : Dr. .Sieinlwch's (Jbservations on Climate
<if |alu. Prof, von Danckelmann, 192 ; the Possibilities of
Long- R.inge Weather Foreca.sts, Prof Cleveland .Mibe, 212;
Floods in the West Midlands, H. .SouJiall. 215 : .Meteorology,
Practical and .Applied, John William Moore, 220 ; Swiss Hail-
stones, 1883-93, Dr. C. Hess, 230; Southerly Bursters,
II. \. Hunt, 230; Dr. Steinbach's Observations at Jaluit
Island, 233 ; Canadian Meteorological Science, 237 ; Aurora
of November 23, 1894, Prof. A. S. Herschel, F.R.S., 246:
.'\uroras in N.E. .Scotland, K. C. Mossman, 622 ; the Study of
Clouds, 248 ; Meteorolog)' in .\rgentina, 253 ; Storm Statis-
tics at Bidston, William E. Plummer, 272 ; a White Rain-
bow, Rev. .Samuel Barber, 274 ; Intercolonial .Astronomy and
Meteorology, 27S ; Solar Heat intercepted by V'olcanic Dust,
Prof A. Bartoli, 279; .Meteorological .Station established at
Angmagsalik, Creenland, 279 : .Meteorological Work in Aus-
tralia, Sir C. Todd, F. R..S.. 306 ; the Gale of December 21-
22, 1894, C. Harding, 311 ; \Ieteorological Results of Balloon
Ascent, by S. .A. Andree, Prof H. A. Hazen, 325 ; Effect of
Gales on Height of Tides, 325 : High Temperature Thermo-
meters of Jena Glass No. 5910, .A. Mahlka, 334: New "Hur-
ricane" .Signal, 344; Das Alpengliihen. Dr. J. .Amsler, 346;
Sular M.ignetism in .Meteorology, Prof F. 11. Bigelow, 356 ;
Variations in Character of Seasons, H. (lawthrop, 357 ; New
Rel.ations between Barometric Movements in Northern
Hemisphere and tho.se of Sun and Moon in Declination, P.
< larrigon-L-agrange, 407 ; the Occurrence of very Cold Days,
416 ; the Recent Storm in the United States, Dr. William H.
Hale, 417; the Invention of the Barometer, Prof G.
•Hellmann, 422 ; Secular Changes of Terrestrial Magnetism,
Dr. L. A. Bauer, 431. 491 : a " Fohn " Wind in the
Riesengebirge, Dr. Kassner. 431 ; Eleven-V'ear Sun-.Spot
Weather Period and its .Multiples, H. Helm Clavton
436 : February Snowfall in the United States, 440 ; Atmo-
spheric Circulation, Prof. M. .Muller, 440; Cause of Cyclones
of Temperate Latitudes, W. H. Dines, 451 ; Recent Russian
Studies of Thunderstorms, R. de C. Ward, 451 : the Moon
and Rainfall, Prof. H. .A. Hazen, 451 : .Anemometry and
\erlical Currents of Atmosphere, M. Ritter, 469 : Report of
Meteorological Society, 469: Meteorological Conditions of
Neighbourhood of Paris for February 1895, E. Renou, 480:
Death of General de Nansouty, 488 : Wind Velocity at Berlin,
Prof. Hellmann, 491, 623 ; Rainfall of Sandwich Islands, Dr.
J. Hann, 500; .Meteorologischc Zeilschrift, 500 ; the Thunder- j
storm of January 23, 1895. W. Marriott, 502 : Phenological
Observations for 1894,' E. .Mawley, 502; "Seiches" in
Lake Derravaragh, J. 11. R. Miicfarlane, 502; Unstable *
Equilibrium of .Atmosphere before Thunderstorm, Prof von. 1
Bezold, 503 : the New \ork Signal Service Office, 539 :
Storm of .March 24, 1895, 513 : Twelve-Vear Intervals in Rise
-and Fall of Temperature, Dr. M. A. \'eeder, 513: the Frost
of February 1895, 525; the Frost of January -February
1895, F. C. Bayard and W. Marriott, 621 : R. C.
Mossman, 621 : Mcition and Formation of Clouds, W. N.
Shaw, F. R.S., 527 ; .Scottish Meteorological Society, 542,
62 1 ; Connection of Latitudinal Displacements of Lines of ]

Barometric Maxima with Declination Movements of Moon,
A. Poincare, 600 ; My Weather-wise Com|>anion, 602 ; this
Winter's .Minimum Temperatures on .Mount Blanc, J. Janssen,
622 ; New .Method of Temperature .Measurement, D. Berthe-
lot, 622 ; Observations on Ten)i>erature and Humidity near
Snow-Surface, Dr. Stiring, 623

Meteors : the Per.seid Meteors, Dr. Brcdichin, 301 : W. F.
Denning, 320 ; the Lyrid .Meteors, 564 ; Bright .Meteor at
Tayport, 587

Metric Standards, New, 420

.Metric System, the, Captain H. R. .Sankey, 562 ; Dr. (■. H.
Gladstone, 563

Metric System : New .Scales adopted in France, 613

Metric System in Tunis, the, 324

Metzner (R.), Study of Combinations of Hydrogen Fluoride with
Water. 24

Meunier (M. Stanislas), Origin of the Lunar Formations, 425

Meyer (Mr.), the Geological Distribution of Fossils, 470

Meyer (Dr. .A. B. ), .Album von Papua-Typen, 174; Two New
Birds of Paradise, 516

Meyer (G.), Capillary Electrometers and Drop Electrodes, 334

Meyer (Prof. L. ), Danger of Explosive Mixtures of .Acetylene
and (Jxygen, 84

Meyer (Prof Lothar von). Death of, 587

Meyer (Prof. V. ), Synthesis of Chloride of Carbon during Pre-
paration of Carbon Tetrachloriile, 131 ; New Method of
Determining High Melting Points, .A. E. Tutton, 161 ; Sodium
Compounds of Nitro- Paraffin, 492

Michael (.A. D.),the History of the Royal Microscopical Society,

335

Microbes and Metals, Mrs. Percy I'rankland, 61 1

Microscopy: Royal Microscopical Society, 95, 191,335; the
History of the Royal Microscopical Society, .A. I). .Michael,
335 ; New Microtome, Messrs. Swift, 191 ; Practical .Methods
in .Microscopy, C. H. Clark, H. G. Wells, 195 ; (Quarterly
Journal of Microscopical Science, 213 ; Death of Dr. (ieorge
A. Rex, 538 ; an Improved Method for the Microscopic
Investigation of Crystals, A. E. Tutton, 608

Microsporon, Paul \'uillemin, 503

Middendorf (E. W. ) " Peru," 388

Miers (H. .A.), Homogeneity of Structure the Source of Crystal
Synimetr}-, 79 ; Precious Stones, and How to Distinguish
them, 545

Milk, Influence of Sterilisation on Digestibility of. Dr. Bendix,
96

Milky Way, the, C. Easton, 327

.Mill (Dr. Hugh Robert), Studies of a CIrowing .Atoll, 203,

Miller (Dr. -A. C. ), .Advantage of High Level Residence f< r
Tuberculous Patients, 370

Milne (Prof John, F. R.S.), the Observation of Earth-Waves
and Vibrations, 548

Minakata (Kumagusu), on Chinese Beliefs about the North,
32 ; Chinese Beliefs about Caves, 57 ; Chinese Theories
of the Origin of .AmlH;r, 294 ; the .\utiquity of the Finger-
Print Method, 199; Fingerprint Method, 274; Iles[)er
and Phb.sphor, 417 ; the Mandrake, 608

Mineralogy: the Structure of Gold .Nuggets, Prof. Liversidge,
F.R.S., 47: Mineralogical .Society, 143, 431, 621 ; Deoth
of Prof. F. Johnstrup, 229 ; .Study of Iron Graphites, Henri
.Moissan, 2()3 ; Death of Prof von Haushofer, 27S ; Gold
Discovered in Isle of Man, 299 ; Lorandile, Prof Krenner, 392 ;
Mas>ive Minerals from India and .-Xustralia, Prof Judd, 431 ;
.Accurate Melhoil of Determining Densities of Solids, Earl of
Berkeley, 431 ; Determination of Mineral Densities, Prof.
Church, 431 ; the Silex of Paris Gypsum, L. Cayeux, 432 ;
Precious Stones, and How to Distinguish them, H. .A. .Miers,
545 ; Traite des Gites Mineraux et .Metalliferes, E. Fuchs
aiul L. de l^unay, 555 : Etude induslrielle des Gites
Metallileres, George Morcau, 555 ; Enargite, Mr. S|)encer,
621

Mines, the Use of Safety Explosives in, 184

Mines, Explosions in, 211

Mines, Palxonlology at the Royal School of, Right Hon. T. 11.
Huxley, F.R.S., '223

Minimum Function, Bollzmann's, S. H. Burbury, F.R.S., 78,
320

Mininnim Tlieorcm, Boltzmann's, Rev. H. W.Watson, F.R.S.,
105 ; Edward 1". Culverwell, 105, 246

Mining: Coal-Dust .an Explo.sivc .Agent, as shown hv an
Examination of the Camerton Explosion, Donald M. D.
Stuart, 26S ; Traite des Giles Mineraux et .Metallileres, E.

XXIV

Index

tSuffiUincHt to .Vaturr,
May 30, 1895

Fuchs and L. de Launay, 555 ; Etude industrielle des Uites

Mctallifercs, llcorge Morcau. 555
Mira Cell. Mr. Fowler, 40

Missing Link, Ur. DulKiis' so-called, 291, 428, 621
Mitchtll (P. Chalmers), Outlines of Bioli^-, 195 ; \ertelirale

Segmentation, 367
Mlanje (Mt. », Captain Manning's Ascent of, 441
Moi^san (ilcnri), the Vaporisation of CartKin, 71 ; Reduction

of Alumina by Carbon, 167 ; the Varieties of Ciraphite, 191 ;

Displacement of Carlxjn by Boron or Silicon in Fused Cast

Iron, 240 ; Study of Iron tiraphitcs, 263 ; Prc|mration of

CIraphitcs Foisonnants, 287 ; Boron Steel, 336 ; Boride of

Iron, 359 : Titanium, 407
Moller (F. I'eckel), Cod-liver 0\\ and Chemistry, 50S
Mollusca : the Homing of Limix;ts, I'rof. C. Lloyd Morgan,

127 : the Habits of Limjiets, I'rof. |. R. Ainsworlh Davis,

511 ; Hermaphro<litisni in .Mollusca, Dr. Paul Pclseneer, 213 ;

Oysters and Typhoid, 391, Mrs. Percy Frankl.tml, 415 ; the

Snail Fauna of the Greater .\ntilles, 524 : Mussel Culture and

the Bait Supply, \V. L. Caldcrwood, 570
Monist, Science in the, 3S1

.Monkeys : a Handbook to the I'rimates, H. O. Forbes, 242
Monte Rosa, Italian Scientific Expe<lition to, Dr. PieroGiacosa,

57

Montefiore (Arthur), the .Samoyad Race, 279

.Mixxly (G. T. (, Studies in Isomeric Change, 620

.Moon, Eclipse of the, 444, 472

.Moon and .-Mmosphcric Waves, M. Bouquet de la Grye, 516

.Mi^ire (B.), the Artificial Spectrum lop, J. M. Finnegan, ,

292
Moore (J. E. S.), the Achromatic Spindle in the Spermatocytes |

of Elasmobranch Fishes, 143 1

Moore (John William), .Meleorolog)-, Practical and Applied, 220 ,
.Morbid .\natomy, .Manual of Practical, II. I). Kolleston and

A. A. Kanthack, 318
Morlmlog)-, the Transmission of Yellow Fever, Dr. .\bery, 300
.Mordey, (W. M.), Slow Changes in Magnetic Permeability of

Iron, 526
More (A. G.), Death of, 538
.Moreau (G.), .\bs<jrplion of Light by Uniaxial Crj'stals, 528;

Etude industrielle des Ciites .Mtlalliferes, 555
.\|organ (Prof. C. Lloyd), the Homing ol Limpets, 127 ;

Intrf)duction to Comjjarative Psychology, 173 ; Psychology for

Teachers, 173 ; the Examination Curve, 617
Morlcydl. Forster), Watts' Dictionary of Chemistr>-, M. M.

Pattison Muir, 27
.Morphology : Morphologic der Erdobcrflache, Dr. .•Mbert Penck,

313; Comparative Morphology of Galeodidu, II. M. Ilernard,

455

Morris (D. K.), the Oucstion of Dielectric Hysteresis, 574

Moscow, .\ntimaly in Direction of Pendulum Line around,
(ieneral Stcbnitskiy, 326

Moscou, Bulletin ile la Socicte de Naturali.stes de, 334, 357

.Mos.<iman (K. C.I, the Frost of 1895, 621 ; Auror;c in North-
Ea-st .Scotland, 622

.Moths: an Observation on, D. L. C. Jones, 79,321; Henry
Cecil, 127: Butterflies and .Moths (Kiitish), W. Furneaux,
W. F. Kirby, 339 ; •• Moths,"' the Fauna of British India, in-
cluding Ceylon and Burma, W. F. Kirby, 605

Motion, Discontinuous, A. B. Ba.sset, F. k.S. , II

Moti (Dr. F. W.), Influence of Sensory Nerves on Movement
and Nutrition of Limbs, 620

Mount I^pgan, Height of, 19

Mount .St. h;iiav. Height of, 19

Mountain .Sickness, H. Kroneckcr, 394

Mountains of California, the, John Muir, 125

Moureaux(N.), Absolute Value of .Magnetic Elements, January I,
1895, 287

Muir (John), the Mountains of California, 125

Muir (.M. M. Pattisfin), Watis' Dictionary of Chemistry-, 27 ;
Ncwth's Inorganic Chemistr)', 52. 107 ; a Treatise on
Chemistry, .Sir H. K. Koscoe, F.K.S.. and C. .Schorlcmmcr,

'■■' !'i- 1 ! 'ir'Ttions for the 'Jnalilalive Chemical

y Complex Mixtures of Salts, 270 ; the
i . , 364, 388, 436 ; Theoretical Chemistry

fioni t)ic .MaM(t|)f>int of Avogn<lro's Rule and Thermodynamics,
Prof. Walter Ncrnst, 530

Muirhcad (B. A.i, Indn-.VIalaynn Spiders, 153

.Mull'T (J. A.), I'isloralifin of Sumatra .Mountain Sy.slem liy
Karlhouakes of May 17, 1893.408

Mtlllcr (I'rof. .M.), Almosphcric Circulatitn, 440

Muller (P. T.), Ebullioscopic Study of Colouring Matters front

Triphenylmelhane, 455
Munro (Dr.), I-ake- Dwelling Research, 621
Munro(R. D. ), Kitchen Boiler Explosions, 197
Muntz (.\. ), Fertilising Material required by Vine, 480
Murphy (Shirley F. ), a Treatise on Hygiene and Public Health,

124
Murray (Dr. John), Chemical Changes between Sea-Water and

Oceanic Deposits, 304
Murray (J.), How to Live in Tropical .•\frica, 364
Murrcn, Eocene Rock at. Right Hon. Sir John Lubbock, F. R.S. ,

94 : Eocene Fossils at, Right Hon. Sir [ohn Lubbock, F. R..S..

223
Muscular Contraction, on the Nature of. Prof. Tli. \V. Engel-

mann, 519
Museum of Natural History, .-Vmerican, 129
.M ushkeloff ( Prof. ), Catalogue of Earthqualtes in Russia, 181
Mushrooms, Edible and Poisonous, Dr. M. C Cooke, 8
Mussel Culture and the Bait Supply, with Reference more

especially to Scotland, W. L. Caiderwood, 578
Mycetozoa, a Monograph of the. .\rthur Lister, O03
Mycologv- : Edible and Poisonous Mushrooms, Dr. M. C Cooke, 8

Naber (H. A.), Standard Methods in Physics and Electricity
Criticised, 318

Naber (Mr.), New Gas Voltameter, 500

Nagaoka(H. I, Changes of Length produced by Magnetisation, 70

Names, the Cyclo|xe<lia of, 434

Nansouty (Max de), Ricours Experinienis to overcome K\x
Resistance to Locomotive at High Speed, 62 ; Koechlin's Wind-
Mea-surements, Experiments at Eiftel Tower, 181

Nansouty (tleneral de). Death of, 488

Natal Observatory, the, Mr. Nevill, 327

National Review, Science in. 162, 259

Natural History : a Natur.ilist on the Prowl, 8 ; .Sir Victor
Brooke, Sportsman and Naturalist, O. L. Stephen, 76;
American Museum of Natural History, 129; the Royal
Natural Historj', R. Lydekker, 197; Die Sehiipfung der
Tierwelt, Dr. Wilhelm H.i.acke, 149 ; the Horn Expedition to
Central -Australia, Prof. Baldwin Spencer, 222 ; a Handbook
to the Primates, 11. (). Forbes, 242 : Birds of the W'ave and
Woodland, Phil Kobin.son. 243: Life at the Zoo, C. J-
Cornish, 276: Snake Cannibalism, H. Tsnagal, 321 ; Baron
C. R. Osten Sacken, 343; J. Schonlan<l, 511 ; the Natura
History of the Solway, G. Stewardson Brady, 322 : Btdletin
de la .Societc de Naturalistes de Moscou, 334, 357 ; Death
and Obituary Notice of Dr. F. B. White, 345 ; in the Guiana
Forest, James Rodway, 3S7 : Orb- Weaving Spiders of the
United States, Dr. Henr)- C. .McCook, Rev. O. P. Cam-
briilge, F. R.S. , 505; Journal of St. Petersburg Society of
Naturalists, 500

N.atural .Science, Philosophy and, David Wcllerhan, 295

Naturalist on the Prowl, a, 8

Nature, the .Sun's I'l.ace in, J. Nonnan Lockyer, C.B., F.K.S.,
374, 396, 565. 590

Nature Knowledge, Short Studies in, William Gee, 557

Nautical .Mmanac, 180S, the, 472

Naval .Vrchilecture : Bilge-Keels and Steailiness in First-class
Battle-ships, Sir William While, 568 : K. E. Froude, 569 ;
X'ibraticm of Steamers, Otto Schlick, 569; W. Mallock, 570;
Mark Robinson, and Capt. 11. R. .Sankey, 570

Naval Engineering : the Limitations of .Screw Propulsion, J. I.
Thornycrofi, F.K.S., and S. W. Harnaby, 562

Niival Officers, the Education of, W. L. ("lowrs, 259

Navigation: .Acoustic Fog Signals, .\. B. Johnson, 130; New
Method of Correcting Courses .it Sea, Dr. George Hay, 215 ;
Ocean Navigation, James Watt and. Dr. Francis Elgar, 475 ;
Corrections of Maximum and Ex-.Meridian Altitudes, j. While,

485

Navigator, Prince Henry the, C. Raymond Beazley, 532

Nebula of ( Irinn, ihe (irealer. Prof. E. \'.. Barnard, 253

Nebula /; 2241, the Parallax nf, Dr. Wilsing, ! 14

Nebula-, New .Stars and, 347

Nco-Vitalisni, Frances A. Welby, 43

Neptune, a Pirssible New Satellite <if, Prof. Schaebcrle, 542

Neptune, ihc Diameter of, Prof. Barnard, 617

Nernst ( Prof. ), Method of Measuring Specific Inductive Capacity
and Resistance of Liiiuids, 232 ; Theoretical Clieniistry from
Ihe Standpoint of .Avogadro's Rule and Thermodynamics,

Suf^lemeni to Na*::
May ja, 1895

■■••1

Index

XXV

Nerves, the Developiiienl of, Adam Sedgwick, F.K.S., 119,

Nervous System, Formatiun Structures of. Prof. Waldcyer, 312
Nests and Kygs of Non-Indigenous British Birds, the, Charles

Dixon, 30
Neuhaus (Dr.), Colour Photography, 503
Ncvill (Mr.), the Natal Observatory, 327
Newall (H. K. ), the .Spectrum of Argon, 454
Newcoml) (Prof.), a Possible New Zone of .-\steroids, 114;

Secular \'ariations of the Interior Planets, 183
New Hebrides, I'^anhiiuake in, 61

New Jersey, the Birds of Kastern Pennsylvania and, 458
New South Wales l.lnnean .Society, 192, 264
New South Wales Royal .Society, 47
New York .Signal .Service Office, the, 539
Newth ((i. S.j, a Text-Book of Inorganic Chemistry, 106: .M.

M. Pattison IVIuir, 52, 107
Newton (Prof. Alfred, K.R.S.), Parrots in the Philippine Islands,

367
Jvewton (Sir Charles, K.C.B.), Death of, 129; Obituary Notice

of, 250
Newton and Co., the .Xrtiticial Spectrum Top, 463
Ney(0.), New Phototheodolite, 515
Niagara, Progress of the Cataract Construction Company's Works

at, 109
Niagara ?'alls, the Utilisation of. Prof. George Forbes, F.K.S.,

205
Niagara and the (ireat Lakes, F. B. Taylor, 619
Nicaragua, the Earthquake of November 1894, in, J. Crawford,

280
Niceville(L. de). New Indo-Malayan Butterflies, 500
Nicolaiew, Strassburg, and Birmingham, on a Remarkable

F-^arthquake Disturliaiice observed at, on June 3, 1893, C.

Davison, Dr. F. von Reuber-Paschwitz, 208
Nile, the. Sir Colin Scott-.Moncriefi', -1^1
Nile Reservoir at .'\ssuan, the, 1 10
Nitrogen and Chlorine, New Compounds of Phosphorus, II. N.

.Stokes, 592
Nitrogen Compounds, a new .Series of. Prof. \'. Pechman, and

llerr Runge, 1 14
Nitrogen Fixation in .'\lgie, Rudolf Beer, 302
Nitrogen Croup, a New Element in the, .\. E. Tutton, 258
Nitromethane, the Kx|)losive Nature of the Sodium and Potas-
sium Derivatives of, .\. F. Tutton, 328
Noetling(Dr.), Similarity of Baluchistan and Pyrenean Echinoids,

2S0
Nogues (.\. .S.), the Child-. Argentine Earthquake of October,

1894. 393
Noll (Dr. F. ), l.ehrbuch der Botanik, Drs. E. Strasburger, H.

.Schenck and A. F. W. .Schimper, 339
North, on Chinese Beliefs aboul ihe, Kumagusu Min.akata, 32
Norway, Earthquake in, 344 ; Dr. Hans Reu.sch, 390
Nova .Vuriga', 516

Numismatics: De.ath of Dr. Hermann Crote, 4S8
Nuovo Giornale Botanico llaliano, 23

Nyasaland, the New Cyiiress of, 85; W. T. Thisclton-Dyer,
• F.R.S., 175

< i.ik Trees in Essex, Remarkable. J. C. Shenstone, 280

<^at-growing l^xperimeiUs, Prof Kinsch, 206

Object-Glass, the New .\chromatic. 160

■Observatories: Ihe Lowe Observatory, 21 : the Lick f)bserva-
tory, .V, Fowler, 201 ; the \'atican (Observatory, 282 ; the
Natal (jbservatory, Mr. Nevill, 327 ; the New Dudley Olwer-
vatory, 327 ; Recent Work at Harvard College Observatory,
Prof. E. C. Pickering, 329 ; the Royal Observatory, Edin-
burgh, 493: Ihe Seismological Observatory Destroyed a'
Tokio. 5,S5 ; Prof. J. W. Judd, F.R,S., 533

Ocean, Critical Revision of" Estimate of .\verage Depth of. Dr.
Karstens, 1 1 1

Ocean Currents, the Travels of Three Bottle- Papers, H. C.
Russell, 35 ; Ocean Navigation, James Watt, ami Dr. Francis
Elgar, 475

Oceanic Deposits, Chemical Changes lietween Sea-Water and.
Dr. John .Murray and Robert Irvine, 304

Oceanic Tenqieralure, al DilVerent Depths, Captain W. J. I..
Wharton, F.R.S., 342

<^)hm, a New Delerminalion of the, F. Himstedt, 571

♦ libers (Wilhelm), Sein Lebcn und Seine Werke, 74

Oldham (\ule), a Pre-Columbian Discovery of America, 8.!

O'Leary (T. S.), the B.>ronieter at Sea, 142

Oliver (Prof. f. E.), Death and Obituary Notice of, 587

Olszewski (Prof. Charles), on the Liquefaction of Gases, a

Claim for Priority, 245
Olszewski (Dr. K.), the Liquefaction and Solidification of .\rgon,

355
Omori (F.), the .\fter-Shocks of Earthquakes, 423
Onnes (Prof. Kamerlingh) : .Magnetic Rotary Dispersion in

Oxygen, 470 ; the Leyden Kryogene I^boratorj-, 408
Optics : .Method of Obtaining Light of Different Wave-lengths in
use in Polarimetric Work, Herr Landolt, 37 ; SuixjrixKilion
of Optical Eflects of Several .Asynniielric Carbon .-\toms in same
Active Molecule. P. .\. (hiye and M. Gauticr, 47; Sujwr-
position of Optical Effects of Different .-\.symnietric CarU)n
.\toms in same .Active Molecule, P. A. Guye and .M. (lautier,
168 ; Kerr's Magneto-Optic Phenomenon,' C. H. Wind, 4S ;
Effects of Monochromatic Light on Series of Pigments, Prof.
H. W. \ogel, 191; (Jttica, Prof. Eugenio (;eleich, 244;
Lens-Work for .\mateurs, Henry Orford, 318 ; the Process of
Light F:mission, G. Jautnann, 334; Yellow-Blue Blind-
ness, Dr. W. Peddle, 335, 621 : Influence of Rhythm of
Successions of Interruptions on Sensitiveness to Light, Charles
Henry, 336 ; Total Reflection of Light in Dense Crystalline
Substances, R. Camerer, 357 ; Refraction in Polychroic
Aureoles, A. .M. Levy, 384 ; Experiments to see if Light-Rays
deviated by .Magnetic Field, M. Curie, 394: Pa.s.sage of Light
across Thin Plate in Case of Total Reflection, Ch. Fabry, 407 :
Experiments on Colour-Sensation, H. W. \ogel, 469: .Mag-
netic Rotary Dispersion in Oxygen, Kamerlingh Onnes. 470 :
Optical Resolutions of a-Oxy-butyric -Kcid, J. .\. Guye .and
Ch. Jordan, 504 ; Action of Light in Protlucing Electric Dis-
charge through Y.acuum Tulx;, Elster and tieikic, 514;
Absorption of Light in Uniaxial Crystals, G. Moreau, 528 ;
F.fl'ect of Rhythm on Xisibility of Signals, Charles Henry, 588 :
the Normal Defect of \ision in the Fovea, C. L. Franklin,
615 ; Polarisation of Oblique Radiation, Dr. W. von Uljanin,

623
Orb-Weaving Spiders of the United States, Dr. Henry C. M.

Cook, Rev. O. P. Camliridge, F. K.S., 505
Orbits, Elliptical, .Mr. H. Larkin, 234
Oregon, Tornado in, 19
Organic Chemistry, the Rise and Development of, Carl

Schorlemmer, 317
Organic Chemistry, the Fatty Compounds, R. Lloyd Whiteley,

557

"Organic Remains oi a I'ornier World, fames Parkinson, the
Author of, Spencer George Perceval, 31

Origin of Classes among the " Para.sol " Ants, Herbert Siwncer,
125

Origins of .-Vrt, the. Dr. E. Grosse, Prof. .A. C. Haddon, 241

Origins of Invention, the, Otis T. Mason, 557

Orion, the Greater Nebula of. Prof. E. E. Barnard, 253

Orion Nebula, Spectrum of the, 471

Orloff (.A.), Catalogue of E.arthquakes in Russia, 181

Ormerod (Eleanor A.), Injurious Insects, 471

Orndorft'(Dr. W. R.), a Laboratory Manual, 77

Ornithology : the Crommelian Collection of Dutch Birds, iS ; the
Nestsand Eggs of Non- Indigenous British Birds, Charles Dixon,
30; .Attitudes adopted by Birds for Concealment, J. E. Harting,
181 : Birds of the Wave and Woodland, Phil Robinson, 243 :
the Tongue and Hyoid .\pparalus of Birds, Herr Schenkling-
Previit, 252 : the .Starling in .Scotland, J. .A. Ilarvie-Brown,
280; British Birds, Claude W. Wyatl, 318 : Summer Studies
of Birds and Books, W. Warde I'owler. 34I : Forest Birds:
their Haunts and Habits, Harry F. Witherby, 34I ; Invasion
of North and North-East Coasts by the Little .Auk, J.
E. Harting, 422 ; Grouse lOxodusin Yorkshire, J. E. Harting,
422; the Bird; of I';asiern Pennsylvania and New Jersey,
458: Death of G. N. Laurence, 4S8 ; Two New Birds of
Paradise, Dr. ,\. li. Meyer, 516; Catalogue of the Birds of
Prey (.Accipitres anil Striges), J. H. Gurney, 532; Sale of
Specimen of Gre.at -Auk, 613

Ornithorhynchus, the X'isceral Anatomy of, F. E. B. Beddard,
F.R.S., 191

Osaka (\. ), .Acidimetry of Hydrogen Fluoride, 430

Oscill.ations, Electric, H. Poincare, I'rof. A. Gray, 361

Osten-S.acken (Baron C. R.), the .Swallowing of one Snake by
another, !2 ; Snake Cannabalisni, 343

Ostroumofl'fDr. ), a Flying Co|)e|ii«l, 20

Ostwald (W.), Die Wissenchaltlichen Grundlasjen der .Ana
lytischen Chemie, J. W. Rtnlger, 482

XXVI

Index

tSuppU-liieKt to Xaiur
May 30, i8g5

Ottica, IVif. Eugenic Gelcisch, 244

Outerbriilge (Ali-.\. E. ), a Claim for Priority, 60S

Owen (Sir Richard*, the Life of. Rev. R. (Iwen, C. Davics

Sherbom. and Right Hon. T. H. Huxley. K.R.S., 169
Oxford (Hcnr^K Lens- Work for Amateurs, 31S
Ox)-gcn, the Explosion of a Mixture of Acetylene and, Dr. T. E.

Thorjie, 106
Oxygen, Magnetic Rotary Dispersion in, K.-\merlingh Onnes. 470
Oxygen Cylinder Explosion, Dr. Dupre"s Refxirl on Compressed,

562
Oysler Culture on the West Coast of France, I'rof. W. A.

Herdman. K.R.S., 162
Oysters and Typhoid, .Mrs. Percy Frankland, 391, 415

I'ace (S. ), (he Z<x)Iogical Record, 223
- Pacific Ocean. Earlhtjuake in. 46S
I'agnoul (M.), .-Kssimilable Nitrogen and its Transformations in

.\rable Land, 622
'■ ^ - 'ility to, Statistics of. Dr. .\. MacDonalil, 299

■ . Japanese .\dditions to, 371
1 Campingpl.-ices ; Worthington G. .Smith's Man —

the I'rimeval .Sav.age, Prof. W. B. Dawkins, K.R.S., 194
I'alicontology at the Royal School of Mines, Right. Hon. T. H.

Huxley, KR.S., 223; Trinucleus, C. E. IJeecher, 619;

Dubois on Pithecanthropoid Remains in Java, Sir W. Turner,

291, 428, 621
P.ipua : .\lbum von Papua-Typen, .\. 1{. Meyer and R.

Parkinson, 174
Parallax of Stars, the Mean, Prof. Hugo (lyldcn, 21
Parasol .\nt,s. Origin of Cla.>«es among the, Herliert Spencer, 125
Parenty ( H. ). Physiological Properties of Oxalate and Crystallised

.Salts of Nicotine, 264
Paris .Vcademy of Sciences, 24, 46, 71, 95. 119, 143, 167, 191,

215. 240, 263. 287, 311, 336, 359, 384, 407, 432, 455, 480,

502, 527. 552. 576, 599. 622
Paris ("■eojjraphical .Society's Prize .V wards for 1895, 489
Paris S'Kriety of Biology, Bequest by I'rof. Pouchet to, 61
I'iirker (G. W. ), Elements of Astronomy, 270
Parkinson (James), the .Xuthor of Organic Remains of a Former

World. Spencer (leorge Perceval, 31
Parkinson (R.), .\. B. Meyer and, Album von Papua-Typen, 174
Parmenticr (General), Distribution of .Minor Planets, 493
I'amicke (.\. ). Die -Maschinellen Hilfsmittel der Chemischen

Technik, 412
Parrots in the Philippine Islands, Prof. Alfred Newton, F. U.S. ,

367
Parthenon, the Condition of the, 35
Pascal, Walter Pater, 381
Pavhwilz ( Dr. E. von Kebjur), on a Rcmirkable Kirlhc|uake

Disturljance ot)scrved at Str.issburg, Nicolaiew, and Birming-
ham on |une 3, 1893, 208
P.i<;/)ualini (Dr.), New .Method of Measuring Small Resistances,

158
Past and Present, Right Hon. T. H. Huxley, F.R.S., i
Pasteur Institute, the, 251
Pater (Walter), Pascal, 381

Pathology, a Text-ljtKjk of, D. J. Hamilton, 148
l'athoIf>gy, Cellular : Photomicrographic Melhiul of .Stuilying

Cell .Motion, Dr. C. L. Leonard, 541
Pavlova (Marie), the .Mastotlons of Russia, 357
Peal (S. E. ), Tan-S|H)is over Do^s' Eyes, 533
Pearson (Prof. Karl), Dillcttantism and Statistics, 145; ihi-

< Irowth of St. I^)uis Children, W'illiam Townsend Porter, 145 ;

Peculiarities of Psychiral Research, 153, 200. 273
Peary Ex|>cdilion : Re|xirted Wreck of the /'itkoii, 1 1 1
Pease (Alfred E. ), Horse Breeding for Farmers, 435
Pechman (Prof. v. ), a New .Series of Nitrogen Com|)ounils, 1 14
Peculiarities of Psychical Research, Prof. Karl Pearson, 27t:

H. G. Wells, 274
!■ "!■ (Dr. W.), a Case of Yellow-Ulue Blindness, 335. 621
> • (B. I).), Thermo-electric Pro|>erlies of j'l.-iiinoid and
'I iiiganine, 280
I' r' r (B. (>.), Electrical Rcsislanre of WimkIs and Stones, 588
I'llii (H.), Force acting at Surface of Sejiaralion of Two

Diclet-trirs, 34
Pcnck (Dr. Allwrt), Mornhologie der Erdolwrflache. 313

''■■'■■' '' i^rimrnl, the Fouraiill, G. A. R., Ji)

^in,|.lc Chronrpgraph, Carl Barus, 84

■ "I Moscow, Anomaly in Dincnon of,

i26
'' il Dublin. W. K. Westropp K.,l,erts. 510

P. r,.lv,In

Pendulum, Observations with Kater's Invariable, V.. V. \.

Love, 516
Pendulums joined by Elastic Thread, Study of System of Two,

Lucien de la Rive, 232
Pennsylvania, Eastern, and New Jersey, the Birds ol, 45S
IVrceval (S|)encer James), James Parkinson, the .\uthor of

Organic Remains of a Former W'orld, 31
Periodic System, Argon and the, Prof. J. Emerson Reynolds,

F.R.S., 486
Periixilus in the W'est Indian Islands, J. 1 1. Hart. 51 1
Perkin (.\. ('•.). Kamala (ii.), 359
Perkin (W. IL, jun. ), Sulptioeamphylic .\cid II., 430; S\ii-

thesis of o-Methylbutyrolactone, 526
Perry (Prof. John, F.R.S.), on the .\ge of the Earth, 224, 341,

582
Perseid Meteors, the, Dr. Bredichin, 301 ; W. F. Denning, 320
Persia, I-'arthquakes in, 298
Peru, E. W. Middendorf, 388

Peter (Dr. .\. ), Experiments with Dormant Seeds, 422
Peters (Dr. C. F. W. ), Obituary Notice of, 179
Peters (Dr. J. P.), Deposit of River .Mluvium as Chronometer

for .Measuring .\ntiquity of Ruin-Mounds, 490
Petit ( P. ), .Vlteralion in Saccharine .Matters during Germination

of Barley, 552
PeyotI Cactus .\lkaloid, the. Prof. L. Lewin, 28S
Phenological Observations lor 1S94, E. Mawley, 502
Philadelphia. Journal of the .-Xcademy of Natuml .Sciences of, 26
Philae, the Nile Reservoir at Assuan, and the Temple of, i to
Philippine Islands, I'arrots in the. Prof, .'\lfred Newton, F. R.S.,

367
Philology : Death of Hyde Clarke, 468
Philosophic, Das X'erhaltniss der, zu der empirischen Wissen-

schaft von der Natur, David Wetterhan, 220
Philosophy and Natural Science, David Wetterhan, 295
Phisalix (C. ), a New .Xnthrax Bacillus (Claviformis). 622
Phonograph, a .Simplified, .\. Koltzow. 58S
Phosphor, Hesper and, Kumagusu .Minakata, 417
Phosjihoretted Hydrogen, a New .Method of Preparing, I'rof.

Ketgcrs, 23
Phosphorus Nitrogen and Chlorine, New Compounds of, 11. N.

Stokes, 592
Photography : M. Marey's Photograjihs of a Tumbling Cat, So :
Photographic Studies of Lunar Surface, MM. Lowy ami
Puiseux, 143; Instrument for .Surveying by Aid of I'hoto-
graphy, J. B. Lee, 191 ; .Advances in Lunar Photography,
Sim. Lo'wy and Puiseux, 207; Foucault's Researches, W. II.
Harrison, 299; H. B-tyard's Researches, W. H. Harri,son,
299 : Dr. .SchiMiiann's \'acuum Sjiectrograph, 423 : Ph<ilo-
graphic Determination of Position of Pole, C. Flaniniarion,
455 : Pht)tographic Measurement of Time in .\stronomy, G.
Lippmann, 455 ; Colour Photography, Dr. Neuhaus,, 503 :
Planetary Photography, C. T. Whitmell, 511 ; Stellar I'hoi.i-
gra|)hy, 516
Photogravure, Gratings used in, Ch. I.ery, 576
I'holonietry, Improvements in, 558
Photometry, Novel .Methods in. Dr. Janssen, 395
Photomicri>graphic Method of Studying Cell-.Motion, Dr. C. I.,

Lecmard, 541
Photolheodolite, New, O. Ney, 515

Physics: Discontinuous Motion, .\. B. Basset, F. U.S., 11 ;
Cap,icily for Heat, V.. II. Griftilhs, 11; Fifth Re|>orl I'l
German Imperial Physico-Technical Institute, 20 ; .Anomalous
Behaviour of Chloroform at very Low Temperatures, Raoul
Piclel, 20: Prof. Boltzmann an<l the Kinetic Theory of Gases.
G. II. Bryan, 31, 152, 176. 319; the Kinetic Theory of
(iases. Dr. J. I.armor, F.R.S.. 152: S. H. Burbury, F.R.S.,
175, 320: I'rof. G. F. Fitzgerald, F.R.S., 221 ; Rev. H. W.
Watson, F. R.S., 222; Prol^. .Arthur Schuster, F. R.S., 293:
Prof. Bollzmann's Letter on the Kinetic Theory of Gases,
Edward P. Culverwell. 78. 581 : Prof. Lu<Uig Boltzmann. 581 ;
Redeteriiiination ftf 'Peinperaltire of Greatest Densit)' of
Water, M. de CopiHl, 37: Gravitation, Dr. J. Joly. F.R.S..
57, 223: Prof. .\. M. Worthington, l-.U.S., 79 ; Prof. Oliver
J. Lodge, F.U..S., 154; Ihe Melhodsfor Determining Density
of. Sea-Water, W. .S. Anderson, 61 ; Effect of Cathode R.ays on
some Salts, Prof. E. ( loldstein, 62, 406 ; the Variations in Level
of Well- Water, A. Ricco, .S. .Arcidiacono, Prof. I'". II. King^
62: Specific Heat of Aniline, E. II. (iriffilhs, 71 ; Physical
.Sorieiy, 71, 142, 239, 3o<), 35*<.,3'<3. 454, 5"°. 55": ihc
Fouraidl Pendulum Experiment, < 1. A. K., 79; a l-'oneanli
IVndiiliini :il Dublin, W. U. Wisiropp Roberts, 510: Cenlral

Sttp/tUiiient to Saitirc^~\
May 30, 1895 J

Index

xxvii

Kuropean River-Temperature Variations, Dr. A. E. Forster,
83 : Berlin Physical .Society, 96, 168, 191, 288, 431, 503, 623 ;
Holtzmann's Mininunn Theorem, Rev. II. W. Watson,
F.R.S.. 105 : Edward I'. Culverwell, 105, 246; the Ratio of
Ihe .S|)ccitic Heats of (Jases, .S. M. Kiirlniry, I''.R..S., 127;
the -Mleged Absoluteness of Motions of Rotation. \. V.. M.
Love, F.R.S.,153, 198; Phenomena connected with Mingling
■of Liquid Masses, E. Kaiser, 158 ; I'rof. Victor Meyer's New
Method of Determining High Melting Points, .\. E. Tutton,
161 ; Vapour Tension and Ilygrometric State, Dr. Verschaf-
feil, 167; Fantastic F'orms assumed by Combinations of
.MUalis and (Jlcic .-Vcid in Contact with Water, Dr. (Quincke,
182 ; .Me.^.surement of Surface Tension of Water in Capillary
Tubes, P. Volkmann, 190; Effects of Monochromatic Light
on .Series of Pigments, Prof. H. W. Vogel, 191 ; I'hos-
phorescence at very Low Temperatures, MM. I'ictet and
.-\ltschul, 206 ; Determination of Specific Heat of Water in
Electrical 'Units, Prof. .\. .Schuster, F. R..S.,and \V. Cannon,
JI4; the Constitution of Volatile Liquids, Prof. Tait, 215;
Kolhermals of Ethylene, Prof. Tait. 215 ; Method of Identify-
ing Former Level of Water after withdrawal of .Solid immersed
therein, Sig. (iuglielmo, 231 ; .Study of .System of Two Pen-
dulums joined by Elastic Thread, Lucien de la Rive, 232 ;
Influence of Force of Gravity on t'irculation. Prof. Leonard
Hill, 23S ; Students" .Apparatus for Determining Mechanical
Ivjuivalent of Heat, Prof. W. E. .\yrton and H. C. Haycraft,
239 ; a Text-book of Sound. E. Catchpool. 244 : the Lique-
faction of Ga.ses, Prof. Charles (Olszewski, Prof. James I )ewar,
F. K.S., 245, 365, 413; .M. M. Pattison .\luir, 364, 388, 436;
Solar Heat intercepted by Volcanic Dust, Prof. A. Kartoli,
279 ; Inability of Cotton Wool lo intercept Low-Temjierature
Radiation, Kaoul Pictet, 280 ; Use of Critical Tem]>eratHre
for Recognition of Purity of Liquids, Raoul Pictet, 288 ; the
Artificial Spectrum To|),Cai>l. W. de W. Abney, C.B., F.R.S.,
292 ; J. M. Finnegan, 11 Moore, 292 ; Dr. F. W. Edridge-
t^reen, 321 ; Charles E. Benham, 321 ; Dr. Dawson Turner,
438 ; the New Laboratories of University College, 298 ; Mea-
surement of Latent Heats of Vaporisation of Various Organic
Liquids, I'rof. Ramsay and Miss Dorothy Marshall, 309;
Critical Point of Liquids holding .Solids in .Solution, R.aoul
I'ictet, 311 ; the Critical Point, Raoul Pictet, 504 ; Determina-
tion of Thermal Conductivity and Eniissivity, Mr. Eumorfo-
jKjulous, 310 ; Influence of Dimensions of Body on Thermal
Fjnissions from Surface, A. W. Porter, 310; Passage of
Oscillator Wave-Train through Plate of Conducting Di-
electric, G. U. Yule, 310 ; .Standard .Methods in Physic* and
IClectriclty Criticised, H. A. Naber, 318 ; the Physical
Society's .Abstracts of Physical Papers from Foreign .Sources,
321 : .\nonialy in Direction of Pendulum I^ine around
Moscow, General Stebnitskiy, 326 ; the Elasticity of Solid
Gelatine Solutions, F>ard Fraas, 326; Electric Discharge
through Gases, Prof. J. J. Thomson, 330; an .'Vutomatic
Mercury \'acuum Pump, M. I'^. Pepin, 334 ; Graphical
Thermo-dynamics, Rene de .Saussure, 334 ; Solution of Salts
in Organic Liquids, C. I".. I.inebarger. 334; Latent Heats of
I'.vaporation of Water, E. II. (Griffiths, 334 ; Temperature of
Maximum Density of Water and its Coefticient of Expansion
in neighbourhotxl of this Tenqjeraturc, I'rof. .Anderson and J.
A. McClelland, 358; Sijnplified Process for Silvering (Slass,
A. and L. Lumiere, 371 ; Simple .Apparatus, W. B. Croft,
383 : the Tin Chromic Chloride Cell, S. Skinner, 383 ;
Physical .Society, Report for 1894, 383 ; Lehrbuch der F'xperi-
mental Physik, .A. Wullner, 387 ; Fluorescence of Solutions,
O. Knoblauch, 406 ; Lowering of Freezing-|)oint of Dilute
Sc:lutions of Sodium Chloride, A. I'onsot, 407 ; the Leyden
Kryogene Laboratory, Prof Kamerlingh Onnes, 408;
iiu Certain (,)uestions of the Theory of Gases, Prof.
I.udwig Boltzmami, 413 ; .Accurate Method of Deter-
mining Densities of Solids, Earl of Berkeley, 431 ;
Determination of Mineral Densities, Prof. Church, 431 ;
Relation of Gravity to Continental Elevation, T. C. Menden-
hall, 430 : Behaviour of Bodies at Critical Temperature, Dr.
-\ltschul. 431 ; .\tomic Weights, Leco(| de Boisbaudran, 432 ;
Preparatory Physics, William j. Hopkins, 436 : the Weight of
a Litre of .Air, I'rof. Mendeleeff, 452 ; Ratio of Specific Heats
of Compound (Ja.ses, Dr. Cap.stick, 452; Maxwell's Theorem
of Equal Partition of iMiergy not inconsistent with Internal
Movements of Gas-Spectra, I'rof. G. I''. FilzgeraUl, !■'. I\..S. ,
452 ; Ideality of .Measurement of Welding in Iron with Regela-
I ion in Ice, T. Wrightson, 453 ; Mechanical -Analogue of Thermal
I'quilibrium between BodiesinContac:,C;. H. Bryan, 454; Melt-

ing-points of Mixtures, H. Crompton and M. A. Whiteley,

454 ; the Laws of Crystalline Absorption, E. Carvallo, 455 ;
Influence of Stress in Corrosion of Metals, T. .Andrews, 470 ;
Physical Work of Hermann von Hehnholl?., Prof. .A. W.
Kiicker, F. R.S., 472, 493; Double Decom|x>sitions of
Vapours, Henr)k .Arctowsky, 477 ; Determination of Critical
Temperature and Boiling-point of Hydrogen, Prof. Olszewski,
488 ; Experiments on .Strength of Canadian Timlrer, Dr. 11.
Bovey, 492 ; Electrification of .Air and other Gases, Lord
Kelvin, P.R.S., Magnus Maclean, and Alexander Gait, 495 ;
Naber's New Gas Voltameter, 500 ; Stoney's I^ocal Heliostat
and Improved Siderostat, 500 ; a Simple Form of Harmonic
Analyser, G. U. Vule, 501 ; Energy .Movements in Medium
Separating Electrified or (Gravitating Particles, H. N. .Allen,
501 ; Condition for Equilibrium between Coexistent Pha.ses,
Mr. Van der W'aals, 504 ; Variation of Hall Effect
in Bismuth with Temperature, 504 ; Observations with
Kater's Invariable Pendulum, E. V. J. Love, 516 ;
Action of Heat on Ethylene, II., I'rof. V. B. Lewes, 526:
Cause of Luminosity in Flames of Hydrocarbon Gases, Prof.
V. B. Lewes, 526 ; Determination of Mass of Cubic Decimetre
of Distilled Water at 4', J. M. de Le|)inay, 599 ; Annual
Exhibition of French Physical Society, 613 ; Disturbances in
Direction of Plumb-line in Hawaiian Islands, E. D. Preston,
619 ; Freezing Points of Binary Mixtures of Heteromorphous
Substances, .Albert Dahms, 619: Critical Tenqwratures of
Mixtures and of Water, F. \'. Dwelshauvers-Dery, 620 ;
Behaviour of Hydrogen to Palladium at X'arious Tem|)era-
tures and Pressures, Bakhuis Roozeboom and Dr. Hoitsema,
624
Physiology : Origin of Dicrotism and Undulations of Systolic
Plateau of Arterial Pulsation, Victor Willem, 46; the Present
State of Physiological Research, 58 ; I'rof. F'rancis Gotch,
F'-R-.S., 103 ; Histological Changes induced in Nerve Cells by
Functional .Activity, Dr. Gustave Mann, 93 : journal of
Anatomy and Physiology, 93 ; Influence of Sterilisation on
Digestibility of Milk, Dr. Bendix, 96 ; Cardiographic Researches
on Mammals, Dr. Cowles, 96, Berlin Physiological .Society, 96,
192, 216, 288, 312, 431, 503, 623 ; Inadequacy of Cell-Theory,
Adam Sedgwick, F. R.S., 119, 213; the Development of
Nerves, Adam Seilgwick, F. R..S., 119, 213; the Cranial
Nerves of \'ertebrates in .Amphioxus, M. van Wijhe, 120 ; the
so-called Organic Chlorine of the (Jaslric Juice, H. Lescrcur,
144; F'.ftect of Temperature on .Secretion of Sweat, Dr. Levy
Dorn, 192; Physiology for Beginners, I'rof. M. Foster,
I'.R.S., and Lewis E. .Shore, H. G. Wells, 195;
Measurement of Blood in Circidalion and Work done by
Heart, Prof. Zuntz, 216; the Mode of Formation of Lymph,
Dr. Cohnstein, 21G; Influence of Force of Gravity on
Circulation, I'rof. Leonard Hill, 238 ; Death of Dr. Studiati,
251 ; Genesis of Intestinal I^piihelium, Etienne de Rouvillc,
288; the Peyotl Cactus Alkaloid, Prof. L. Lewin, 288;
EITect of Suspension of Head on Circulation, Dr. G.
Joachimstal, 288 ; the Terminations of Motor Nerves in
Muscles, Mr. Seeler, 288 : Formative Structures of Nervous
System, I'rof. Waldeyer, 312: Death of Dr. E. Kiilz, 324:
Influence of Nervous System on Glycose I'ormation and
Histolysis, M. Kaufmann, 360 ; New Method of .Staining Cells
with Aniline Dyes, Dr. Kawitz, 431 ; Action of Intravenous
Injections of Sodium Chloride on Com|x)sition of Lymph and
Blood, Dr. Cohnstein, 431 ; Modifications of Blood by
Thermal Treatment with Bourboule Water, Ph. Lafon, 432;
Dual Brain .Action, L. C. Bruce, 441 ; Physiological .Action
of Black-Damp, Dr. John Haldane, 477 : Dr. M. Foster on
the Teaching of Physiology in .Schools, 487 ; I Glycogen in
Blood, M. Kaufmann, 503 ; Relative Signification of Dis-
engagement of Carbonic Acid and Absorption of Oxygen bv
Muscles, J. Tis.sot, 503 ; ICffect of Lo.ad <m Metabolism and Bixly-
Functions of Soldiers on the March, I'rof. Zuntz, 303 ; I'reo-
/luhanol, M. Franchimont, 504 ; on the Nature of .Mu.scular
Contraction, Prof. T. H. W. Engelmann, 519: .\llgemeine
Physiologie, MaxVerwom, Dr. M. Foster, F. R.S.. 529: Elec-
trophysiologie, I'rof. W. Biedermann, I'rof. J. Burdon Sander-
son, F. R.S.. 553; Development of Branches of Fifth Cranial
Nerve in .Man, A. F. Dixon, 599 : Influence of Sensory
Nerves on Movement and Nutrition of Limbs, Drs. .Mott
and Sherrington, 620 ; the Formation of Uric .Acid in .Man, Dr.
Weintr.rud. 623 : Propyl .Alcohol as Separator of Cholesterin
.Skin-Fats into High and Low Melting-Points, Prof. Liebreich,
623 ; Tuberculous Clerms possessed of Locomotive Power, I).
Mac Gillivray,623 ; Origin of the Amnion, Prof. Hubrecht, 624

XXVUl

ludi

'ex

tSiiffiUttient to Nature,
May 30, 1895

I*ictet (Raoul), Anomalous Behaviour of Chloroform at verj- Low
Temperatures, 20 : Phosphorescence at very Low Tempera-
tures, 206 : Inability of Cotton-Wool to intercept Low Tem-
[lerature Radiation, 2S0 : Use of Critical Temperature for
Recognition of Purity of Liquid, 28S : Critical Point of
Liquids holding Solid in Solution, 31 1 : Influence of Low Tem-
peratures on Attractive Power of Artifical Permanent Magnets,
384 : the Critical Point, 504
Pictet (Dr.), Intense Cold as a Theraiieulic Application, 5S8
Pickering (Prof. E. C. ), Stars having Peculiar Spectra, 302 ;

Recent Work at Harvard College ( )bser\ator\-, 329
Pickering (Prof. W. H.), Schiaixirelli on Mars, 87: Lunar

River IJeds and Nariahle .Spots, 5S9
Pickworth (Charles X.), the Slide Rule, 77

Pierid.-e, Pigments of, K. C. Hopkins, 142

Pigeon (Leon), New Method of Preparation of Chloroplatinous ;
-Acid, 552

Pigments of Pieridre, F. G. Hopkins, 142

Pipes, Cleaning Tobacco, Cecil Cams- Wilson, 511

Pisciculture: the .Artificial Hatching .if Marine Food- Fishes,
Prof. Mcintosh. 156 ; Oyster Culture on the West Coast of
France, Prof. W. .\. Herdman, F. R.S., 162 ; Death .md
Obituary Notice of Thomas .Andrews, 279

Pithecanthropus Erectus, eine Menschen;vhnliche Uebergangs-
form .aus J.ava, E. Dubois, 291. 42S, 621

Pizzetti (Prof. P.), I Fondamenti .M.ite:iiatici per la Critica dei
Risultati Sperimentali. 77

Planetary Photography, C. T. Whitmell, 511

Planets: the Transit of Mercury, 40, 85, !6o, 253: Recent
Obser\ations of Jupiter, Prof. E. E. Barnard, .85 ; W. F.
Denning, 227 ; Pseudo-Satellites of Jupiter in the Seventeenth
Centurj', Charles W. L. Johnson, 285 : Observations on Mars,
40 ; .Schiaixirelli on Mars, Prof. W. H. Pickering, 87 : Mars
in 1894, G. Schiaparelli, 395 ; Seasonal Changes on NIars. Mr.
Percival Lowell, 259 ; the Satellites of Mars, Prof. Campbell,
443 ; Secular Variations of the Interior Planets, Prof. New-
conili. 183: an Im|x>rt.ant .\steri)ii1, M. Tisserand, 234:
the Planet Earth, an .Astronomical Introduction to Geography,
R. A. Gregory, 291 ; Spectroscopic Measures of Planetary
Velocities, M. Deslandres, 443 : Distribution of .Minor Pl.anets,
General Parmentier, 493

Plant-Houses, Green Glass in, 514

Plants: Mechanism of the Respiration of, L. M.iquennc, 24 :
Variation in .Animals and Plants. Prof. W. F. R. Weldon,
F.R.S.,449; Do Plants .Assiniil.iie Argon? E. Blass, 461 :
Prof. W. Ram.say, F. R.S., 461 : a Popular Treatise on the
Physiology of I'lants, Dr. Paul Soraucr, 554 ; Practical
Physiology of, Francis Darwin, F. K.S., and E. Hamilton
Acton, 577

Platypus Embryo from Intrauterine Egg, J. P. Hill, and C. G.
Martin, 264

Plimpton (R. T. ), Use of Barium Thio.sulphate in Standardising
Iodine Solution, 526

Pliocene not Miocene, the Burmese Chipped Hints, Dr. W. T.
Stanford, F.R..S., 608

Plon Biological Station, the, 278

Plumb-line in Hawaiian Islands, Disturbances in Direction of,
E. D. Preston, 619

Plummcr (William E.), Chronometer Trials, 153; Storm
.Statistics at Bidston, 272

Pocock (R. I.I, Malaysian Spiders, Thomas and M. E. Work-
man, 99 : some Suggestions on the Origin and Evolution of
Web-.Spinning of Spiders, 417

Podmore (Frank), -Apparitions and Thought Tran.sference, H. G.
Wells, 121

Polncare (.A.), Connection of Latitudinal DispLacemenlsof Lines
of Barometric .Ma.xima with Declination .Movements of Moon,
600

Poincar^ (H.), Lcs Oscillations Elcctriqucs, 361 ; the IHuted
S|)cctnim, 599

Poincare (Lucien), a Class of Secondary Batteries, 528 ; a Battery
with Liquid Metallic Electro<lcs, 563

Polar Cajis of Mars, the, 64

Polarimetric Wf)rk, Meth'Kl iA r>btaining Light of Different
Wavelengths in Use in, Herr I^andoli, 37

Polarisation of Oblique Radiation, Dr. W. von Uljnnin,
623

Polyembryony, M. Tretjakow, 540: I- rank J. Cole, 558

Ptinwit (A.), Lowering of Freezing- Point of Dilute Solutions
of .SiMlium Chloride. 407

Po >lc ( R. S. ), Death and (jbUuary Notice < f, 370

Pope (F. G.), Elementary Practical Chemistry, Inorganic and

Organic, 364
Pope (William J.), the Use of the Cdobe in Crystallography.

223 : Melting Points of Raceniic Modifications and Optically

.Active Isnnierides. 526
Porro (Francesco). .Aslronomica Sferica, 53
Port Erin Marine Biological Station, the. Prof. Herdman, 281
Porter (.A. W. ), Influence of the Dimensions of Body or»

Thermal Emission from Surface, 310; the (Question of

Dielectric Hysteresis, 574
Porter (William Townsend), the Growth of St. Louis Children,,

Prof. Karl Pear.son, 145
Pouchct (Prof.), Bequest to Paris .Society of Biology, by, 61
Poulton (Edward B.. F. R.S.), .Acquired Characters. 55, 126
Pt>wer, on the Development and Transmission of, Prof. Williani

Cawthorne Unwin. F.R..S., 124
Prain (Dr.), the Bhang Plant, 143
Precious Stones, and How to Distinguish them, H. .A. Micrs,

545
Prccambrian Rocks, the Barrenness of. Dr. C. Callaway. 462
Preece's (W. H., F.R.S.), Method of Telegraphy by Induction,

587
Prehistoric Ceramics from I^ngcnlebarn Tunudus, J. .Szombathy,
157 ; Prehistoric Objects in North-east Italian Museum, Dr.
Hoernes, 157
Preller (Dr.), Fluvioglacial and Interglacial Deposits in

Switzerland, 575
Present, Past and. Right Hon. T. H. Huxley, F.R.S., I
Pressures in liuns. the Measurement of. Rev. F. Bashforth, 461
Prestwich (Joseph, F. R.S.I, Collected Papers on some Contro-
verted (,)ueslions of tleologj', 601
Primitive Culture, Woman's .Share in, O. T. Mason, 244
Prince Henry the Navigator, C. Raymond Beazley, 532
Pringsheim (Nathan.iel). Obituary Notice of. Dr. H. Scott, 399
Priority, a Claim for, .Alex. E. Outerbridge, 608
Proceedings of the Chemical Society, the. Prof. Williant

Ramsay, F. R.S. , 294
Propane, the Properties of Liquid Ethane and, A. E. Tutton, 65
Prothero (Prof. ), History as a Science, 162

Psychology : Psychologic des lirands Calcidateurs and Joueurs
d'tchecs, .Alfred Binet, Francis Galton, F. R.S., 73: .Appari-
tions and Thought Transference, Frank Podmore, II. G.
Wells, 121 : Pecidiarities of Psychical Research, Prof. Kart
Pear.son, 153, 200. 273; Edward T. Dixon, 200, 223; Prof.
Oliver J. Lodge, F.R.S., 247: H. G. Wells, 274: Lecturei
on Human and -Animal Psychology, Wilhelm W'undl, 173 :
I'lrundrissder Psychologic, Oswald Kidpe, 173: Introduction
to Comparative Psychology, C. Lloyd Morgan, 173: Psycho-
logy for Teachers, 173; Primer of Psychology, George
Trumbull Ladd, 173 : Dr. Gilbert's Researclies on Develop-
ment of .School Children, 232 ; Dual Brain Action, L. C.
Bruce, 441
Puiseux (M.), Photograjihic Stu<lies of Lunar Surfaces, 143;

Advances in Lunar Photography, 207
Pupin (.M. J.), Resonance .Analysis of .Alternating Currents, 93,

190; an Automatic Mercury Vacuum Pump, 334
Putnam (Prof. F. W.I, Copper-Sheathed Objects made by
.Aboriginal Metallurgists of .America, 490
1 Pyrometers, the Testing of Platinum, Dr. W. Wicn, 623

Quarrying of Granite in India, the. Dr. II. Warth, 272

(,)uarlerly Journal of Microscopical Science, 213

<^)Haternions : .Anwendung der (,)uaternionen auf die Geomelric,
Dr. P. Molenbrock, 76 ; the (Jutlines of (Quaternions, Lieut. -
! Colonel II. W. L. Hime, 76, 154; the Elements of, Lieut. -
: Colonel H. W. L. Mime. 201

Quincke (Dr. ), Fantastic Forms .Assumed by Combinations of
I Alkalies and (Jleic Acid in Contact with Water, 182

' Races, Early British, Dr. J. G. ('.arson, 67, 90
Racovitza (E. G.), Role of .Amrebocytes in Annelids, 455
Raclclifl'e Catalogue, the, 183
Radiant .Suns, .Agnes Giberne. 1 74
Rainbow, a While, Rev. Samuel Barber, 274
Rainmaking and .Sunshine, John Collinson, 7
R.am.Tge (II.), the Volmnetric Determination of Mang.inesc, 454
Rambaut (Dr. I, .Alnios|)hcric Dispersion, 396
Ramsiy (.A.), the " Baric" Condition of the Atmosphere, 84
Ramsay (Sir .Andrew Cronibie), Memoir of, Sir .Archibald Geikic,

. 385

SnppUment to Nature, ~\
May 30, 1895 J

htdex

XXIX

Kamsay ( Prof. William, F.R.S.), the Proceedings of the Chemical
Society, 294 ; Measurement of Latent Heatsof X'aporisation
of \'arious Ort;anic Liquids, 309 ; the New Constituent of the
Atmosphere, 347 ; Do Plants Assimilate Argon ? 461 ; Ter-
restrial Helium (?), 543

Kanyard (A. C. ), Obituary Notice of, 179

J\atio of the Specific Heats of Gases, the, S. H. Burlniry, K.R.S.,
127

Kawitz (Dr.), New Method of Staining Cells with .\iiiline Dye,

431
Kawlinson (.Sir Henry, I'.R.S.), Death of, 440 ; Olntiiary Notice

of. 535
Rayleigh (Lord, Sec. U.S.), the New Constituent of the Atmo-
sphere, 347
Reddro]) (J.), the Volumetric Determination of Manganese, 454
l\eed(\V. .Maxwell), Irregularities in \'ariable Stars, 183
kegnauld (I'rof Jules), Death of, 392
Keinsch (Dr.), Bacteriological Investigation of Altona Water-

Supply, 231
keise nach Siidindien, Kmil Schmidt, loi
Reliquary, Science in the, 382
Renuu (E.), Meteorological Conditions of neighbourhood of

Paris for February. 1895, 480
Research in Education, Dr. H. E. Armstrong, K. R.S. , 463
Research. Physiological, the Present State of, 58; Prof. Francis

Gotch, F.R.S., 103
Research and Publication, Endowment for Scientific, Addison

Brown, 164, 186
Respiration of Plants, Mechanism of, L. Maquenne, 24
Retgers (Prof), a New Method of Preparing Phosphoretted

Hydrogen, 23
Reusch (Dr. Hans), Earthquakes in Norway. 390

Reviews and our Book Shei.k —

A Dictionary ef the Economic Products of India, George

Watt, 4
Butterflies from China, Japan, and Corea, John Henry

Leech, 6
Rainmaking and Sunshine, John Collinson, 7
The Elements of Graphic .Statics ; a Text-book for Students

of Engineering, L. M. Hoskins, 7
A Naturalist on the Prowl, 8
From .Spring to Fall, 8

Edible and Poisonous Mushrooms, Dr. M. C. Cooke, S
Thef)phrastus of Eresus, on Winds and on Weather Signs, 25
Travels amongst American Indians, their Ancient Earthworks

and Temples, Vice-Admiral Lindesay Brine, 26
Journal of the Academy of Natural Sciences of Philadelphia,

26
Watts' Dictionary of Chemistry, 27
Text-book of the Diseases of Trees, Prof R. Hartig, W. R.

Fisher, 28
Le centre de I'Afrique : Autour du Tchad, P. Brunache, 29
Helical Gears, 30
The Nests and Eggs of Non-Indigenous British Bir<ls, Charles

Dixon, 30
Commercial Geography, E. C. R. (jonner, 30
' Dynamometers and the Measurement of Power, John J.

Flather, 30
F'lectric Light and Power, Arthur F. Guy, 30
The .Science of Mechanics ; a Critical and Historical Exposi-
tion of its Principles, D. Ernest Mach, Prof. A. G.

Crreenhill, F. U.S., 49
A Text-book of Inorganic Chemistry, G. S. Xewth, M. M.

Pattison Muir, 52
Astronomia Sferica, Francesco Porro, 53
The New Technical Educator, 53
Index Kewensis Plantarum Phanerogamarum, 54
Alpine Climates for Consumption, H.J. Hardwicke, 54,
Psvchologie des tlrands Calculateurs et Joueurs d'Echccs,

.\lfred Binct, F'rancis flalton, F.R.S., 73
Wilhelm Olber.s, sein Leben und seine Werke, Dr. C.

Schilling, 74
Anweiulung der Quaternionen auf die Geometrie, Dr. P.

Molenljrock, 76
The Outlines of (,)uaternions, Lieut. -Colonel II. W. 1,.

Hime. 76
Sir \'ictor Brooke, Sportsman and Naturalist, O. L. Stephen,

76
A Text-book of Dynamics, a Text-book of Statics, William

Briggs and C;. H. Bryan, 76

The Slide Rule, (Jh ine^ .\. Pickworlh, 77

I Fondamenti Matematici per la Critica dei Risultati Speri-

mentali. Prof P. Pizzetti, 77
Teppich-erzeugung im Orient, 77
A Laboratory .Manual, W. R. Orndorff, 77
The Construction of the Modern Locomotive, George Hughes,

N. J. Lockyer, 97
Malaysian Spiders, Thos. and M. E. Workman, R. I. Pocock,

99
The Deserts of .Southern France, an Introduction to Lime-
stone and Chalk Plateaux of Ancient Aquitaine, S. Baring-
Gould, Canon Bonney, F. R..S., 100
An Elementary Treatise on Theoretical Mechanics, Alexander

Ziwet. loi
By Order of the Sun to Chile to see his Total Eclipse, April 16,

1893. J. J. .\ubertin, lOI
Reise nach Siidindien, Emil Schmidt, lOI
By \'ocal Woods and Waters, Edward Step, 102
Apparitions and Thought Transference, Frank Podmore,

H. G. Wells. 121
The Dawn of Civilisation, Egypt and Chaldaja, G. Maspero,

122
On the Development and Transmission of Power, William

Cawthorne Unwin, F.R.S., 124
A Treatise on Hygiene and Public Health, Thomas Stevenson

and Shirley F. Murphy. 124
Involution and Evolution according to Philosophy of Cycles,

Kalpha, 125
The Mountains of California, J. Muir, 125
The Growth of .Sc. Louis Children, William Townsend Porter,

Prof Karl Pearson, 145
The Principles of Water-works Engineering, J. H. Tudsbery

Turner and .\. W. Brightmore, 146
The Water Supply of Towns, W. K. Burton, 146
A Text-book of I'atholog)', Systematic and Practical, D. J.

Hamilton, 14S
The Mechanism of Weaving. T. W. Fox, 149
Memorials of Old Whitby, Rev. J. C. .\tkinson. 149
Die Schopfung der Tierwelt. Dr. Wilhelm Haacke, 149
The \'accination (^>uestion, .Vnhur Wollaston Hutton, 149
Dr. William .Smellie and his Contemjxiraries, John Glaister,

149
The Life of Richard Owen, Rev. Richard Owen, 169
Electromagnetic Theoiy, Oliver Heaviside, F. R.S., J. Swin-
burne, 171
Lectures on Human and Animal Psychology, Wilhelm Wundt,

173
Grundriss der Psychology, Oswald Kuipe, 173
Introduction to Com|>arative Psychology, C. Lloyd Morgan,

■73
Psychology for Teachers, C. Lloyd Morgan. 173
Primer of Psycholog)-, George Trumbull Ladd, 173
R.adiant .Suns, .\;'ncs Giberne, 174
Album von Papua-Typen, .\. B. .Meyer and R. Parkinson,

174
Farm Vermin, Helpful and Harmful, 174
A Treatise on Chemistry, .Sir H. E. Roscoe. F. R.S.,andC.

Schorlemmcr, F. R.S., M. .M. Pattison Muir, 193
Man — the Primeval Savage. Worthington G. Smith, Prof W.

Boyd Dawkins, F.R.S., 194
Physiology for Beginners, Prof. M. Foster, F". R. S. , and Lewis

E. Shore. H. (i. Wells, 195
Outlines of Biolog)-. P. Chalmers Mitchell. H. G. Wells, 195
Practical Methods in Microscopy, C. H. Clark, H. G. Wells,

.'95.
Climbing and E.^cploration in the Karakoram-Himalayas. Wil-
liam Martin Conway, F.S..\.. 196
The Royal Natural History, Richard Lydekker, F. R.S. , 197
Kitchen Boiler Explosions, R. D. Munro, 197
The Island of M.ideira, for the Invalid and Naturalist, Sui^eon-

(iencral C. .\. Gordon, 197
Biological Lectures and Addresses delivered by the late .\rthur

Milnes Marshall, F.K.S., 217
.Vdvanced .\griculture, H. J. Webb, 2l8
The Steam Engine and other Heat Engines, Prof. J. A. Ewing,

F.R.S., 219"
Das \erhaltniss der Philosophic zu der empirischen Wissen-

schaft von der Natur, David Welterhan. 220
Meteorolog)-, Practical ami .\pplied, John William Moore,

220
The Province of South Australia, 1. D. Wood. 221

x.xx

Index

tSiippU-nieHt to Xaiiti^
May 30, 1895

Measurement Conversion Diagrams, Robert \l. Smith, 221
Die .Anfange der Kunst, Dr. E. Grosse, I'rof. A. C. Haddon,

241
A Handbook to the Primates, H. O. Forbes, 242
Birds of the Wave and Woodland, Phil. Robinson, 243
Studies on the Ecto|xirasitic Trematodes of Jaixin, Seitarf>

Goto, 244
Woman's Share in Primitive Culture, O. T. Mason, 244
.\ Text-Book of Sound, E. C^itchpool, 244
Ottica, Prof. Eugenio ( leleich, 244
Zeil- und Streitfragen der Biologie, I'r.if. Dr. Osc.ir Hertwig,

G. C. Bourne, 265
Coal-Dust an Explosive .Agent, as shown by an Examination

of the Camerton Explosion, Donald .M. P. .Stuart, 26S
Die EeWnsweise der Meeresthiere. J<»hannes Wallher, 269
Elementary (Qualitative Chemical .Analysis, I'rof. Frank

Clowes, and J. B. Coleman, 270
Tables and Directions for the Qualitative Chemical An.^dysis

of Moderately Complex Mixtures of Salts, .M. .M. Pat'.ison

Muir, 270
laboratory Exercise Book for Chemic.il Students, E. Francis,

270
Elements of Astronomy, G. W. Parker, 270
Lehrbuch der V'ergleichenden .Anatomic, Arnold Lang, I'rof.

E. Ray Lankester, F.R.S., 289
Eehrbuch der Petrographie, Dr. Ferdinan<l Zirkel, 290
Pithecanthropus Erectus, cine Menschenaehnliche Ueber-

gangsform aus Java, E. Dubois, 291
The Planet Earth, R. .A. tJregor)-, 291
Eilhogenesis der Gegenwart, Johannes Walther, 313
( leotektonische Problemc, .A. Rothplctz, 313
Morphologic der Erdoberfl.iche, Dr. .Vltjert I'cnck, Dr. J. W.

Gregor)', 313
The Rise and Development of Organic Cheniistr)-, Carl

Schorlemmer, F. R.S., 317
British Birds, Claude W. Wyatt, 318
St.andard .Methrnis in Physics and Electricity Criticised, .ind a

Test for Electric .Meters Pro|x)sed, II. .\. N'aber, 318
Electrical Engineering, for Electric Eight .Artisans and

Students, W. .Slingo and A. Brooker, 318
Lens-Work for Amateurs, Henry Orford, 318
Manual of Practical Morbid Anatomy, II. D. Rolleston .".nd

A. .A. Kanthack, 318
lehrbuch der Botanik, Drs. E. Strasburger, V. Noll, H.

Schenck and .\. F. \V. .Schiniixrr, 339
Butterflies and Moths, British, W. Furneaux, W. F. Kirhy,

339
Die Rcsultate der Aetzmethode in der krystallographischen

Forschung, an eine Reihe von krystallisirten Korpern

dargestellt. Dr. M. Baumhauer, 340
Summer Studies of Birds and Books, W. Warde Fowler, 341
Forest Birds, their Haunts an<l Habits, Harry F. Witherby,

341 . .

I..es Oscillations Electriqucs, H. Poincare, I'rof. .\. Gray, 361
The Book of the Rose, Rev. A. Foster-Melliar, 362
I/Industric des .Araneina, Woldemar W.agner, 363
Elementary Practical Chemislr)', Inorganic and Organic, J. T.

Hewitt, 364
How to Live in Tropical Africa, J. Murray, 364
Memoir of Sir Andrew Cronibie Ramsay, Sir Archibald Geikie,

38s
Har«°ard College by an Oxonian, George Birkbeck Hill, 386
Tableau Melricpie <le Logarilhnirs, C. Dumesnil, 3S6
In (fuiana Forest, James RcMlway. 387
lA:hrbuch der i;x|)erinienlalphysik, A. Willlner, 3S7
Peru, E. W. Middendorf, 388

llandbuch der Slereochcmic, Dr. C. .A. Bi.schoff, 409
Les .Abimes, les eaux souterraines, les cavernes, les sources,

la siiela-ologic, E. A. Marlel, 410
Bulletin of the Botanical Department, Jamaica, W. Fawcell,

412
Die Masrhinellen Hilfsmitlcl der Chemischen Technik, A.

Parnirke. 412
.Air, Water, and Disinfcclanls, C. M. Aikman, 412
An Elementary Text-book of Anatomy, Prof. II. E. Clark,

412
AmnhioxHs and the Ancestry of the Vertebrates, Arthur

Wille)-, 43.1
Th? ( ycloparlia of Names, 434

Varied Occuintions in Weaving, Ij uisa Walker, 435
llor«: Breeding for Farir.crs, Alfred E. Pease, 435

Prejiarator)- Physics, William J. Hopkins, 436

The Story of the Stars, George F. Chambers, 436

Aerial Navigation, 436

The Life and Correspondence of William Buckl.and, F. U.S.,

Mrs. Gordon, 457
The Birds of Eastern Pennsylvania and New Jersey, 458
Conspectus Flonv Africa, on Enumeration des Planles

d'Afrique. Th. Durand et Hans Schinz, 459
Le<;ons de Chimie, H. Gautieret G. Charpy, 499
Lehrbuch der Bakieriologischen Cn.ersuchungund Diagnostik,

Dr. Ludwig Hein, .Mrs. P. Franklaml, 481
Die wLssenchaftlichen Grundlagen der analytischen Cheniie,

W. Ostwald. J. W. Rodger, 482
.An Introductory Account of Certain Modern Ideas and

Methods in Plane .Analytical Geometry, Charlotte -Angas

Scott, 483
Les Aurores Polaires, .Alfred .\ngot, 484
-A Few Chapters in .Astronomy, Claudius Kennedy, 4S4
.Mechanics for Colleges .and Schools: Statics, R. T. Gla.'o-

lirook, F.R.S., 484
Tlio Telegraphist's Guide, James Bell, 4S4
.\merican Spiders and their .Spinning Work, Henry C

.\IcCook, Rev. O. P. Cambridge. F.R.S., 505
Sja and Land, Features of Coasts and Oceans, with Special

Reference to the Life of Man, N. S. Shaler, 507
Cod-liver (Jil and Chemistry, F. I'eckel ^toiler, J.

Cameron, 508
Astronomische Chronologie, W. F. Wislicenus, 509
Die altesten Karien der Isogenen, Isoclinen, Isodynanion,

Prof. Dr. (;. Hellman, 509
.An Elementary Text-Book of Hydrostatics, W. Briggs and (J.

Bryan, 509
.Allgemeint Physiologic, Max \'er\vorn. Dr. M. Foster, F. R..^.

529 . .

Theoretical Chemistry, from, the Standpoint of .Avogadro's
Rule, and Thurmoilynamics, I'rof. Walter Nernst, M. M.
Pattison Muir, 530

Bird Notes, Jane .Mary Hayward, 532

Catalogue of Birds i>f Prey (.Accipitres and Striges), J. II.
( lurney, 532

Prince Henr)' the Navigator, C. Raymond Beazley, 532

.An Elementary Treatise on Theoretical Mechanics, Alexander
Ziwet. 533

Kleclrophysiologie, W. Biedermann, Prof. J. Burdon Sander-
son, F.R..S., 553

.\ Popular Treatise on the Physiology of Plants, for the Use of
Gardeners, or for Students of Horticulture and of .Agricul-
ture, Dr. Paul Sor.'.uer, 554

Traite des Cites Mineranx et Mclallileres, E. Fuchs and L. de

, Launay, 555

Elude industrielle des (iites Metallifcres, George Moreau, 555

Elementary Text-Book of Metallurg)-, -A. Humboldt -Sexton,

556
Annals of British (leology, J. F. Blake, 557
The Origins of Inventiim, OtisT. .Mii.son, 557
.Short Studies in Nature Knowledge. William Gee. 557
Organic Chemistry, the Fatty Comi)ounds, R. Lloyii Whileley,

557
Practical Physiology of Plants, l*rancis Darwni, 577
.Mussel Culture and Bail Supply, with reference more especially

lo .Scotland, W. L. Calderwood, 57S
.\ History of Epidemics in Britain, Charles Creighton, 579
Grundziige der .Mathematischen Chemie, Dr. G. Helm, 580
Die Bearlieitung iles Glases auf dem Blasetische, 1). Djakiriow

und W. Lermanloff, 580
Problems and Solutions in Elementary Electricity and Mag-
netism, W. .Slingo and A. Brooker, 580
Qualitative Chemical .Analysis of Inorganic Substances, 580
Collected Papers on some Conlroverted (Juestiims of Geology,

Joseph Prestwich, Prof. J. W. Judd, F. R.S., 601
■My Weather-wise Companion, 602
A MoEiograph of ihe Mycelozoa. being a Descriptive Cualogue

of Ihe Species in ihe British .Museum, .Arthur Lisler, 603
I_a Pratiipie dn Teinturier, Jules Gar^on, J. S. M. Gardiner,

604
The Fauna of British India, including Ceylon and Burma, W.

F. Kirby, 605
Ueynohls (Prof. J. Emerson, F.R.S.), Argon and the Pjrio-lic

.System. 486
Rex (Dr. Geo. .A.), De.alh and Obif.nry Notice of, 53S
Rhynch"demus Terrestris in En'^lanl, I". W. Gamble. 33

May 30, 1895 J

Index

.\ \ X I

Khynchodemus terrcslris in Germany, H. Simroth, 294
Rhodologia, J.- C. Sawer, 39

Kicco (A.) the Variations in Level of VVell-waler, 62
Kicco (I'rof. ), the Sicihan Karlhquakes of August 1894, 207
Richard (Jules), Gases of Swimming Bladder of Fishes, 576
Richmond (James G.), the Recent Auroral I'henomenon, 581
kicour's Kxi^eriments to Overcome Air- Resistance to Locomo-
tive at High Speed, Max de Nansoiity, 62
Ridley (Mr.), Kormica Smagdarina, 95

Rippon (H. I'. I, the Hird-Winged Butterflies of the East, 343
Kitter (M.), Anemometry and \'ertical Currents of Atmosphere,

469
River Temperature, Methods of Determining Influence of

Springs on. Dr. II. B. Guppy, 119
River-Tem]X'rature Variations, Central European, Dr. A. E.

Eorster. 83
Roberts (W. R. Weslropp), a P'oucault I'endulum at Dublin, 510
Robertson ( R. ), Electrical Haulage at Earnock Colliery, 469
Robinson (.Mark), Vibration of Steamers, 570
Robinson (I'hil), Birds of the Wave and Woodland, 243
Roborovsky (M.), Survey of Lukchun (Tibet) Depression, 491
Rocks, the Study of, 290
Rodger (J. W. ), the Electric Conductivity of Pure Water, 42 ;

Die wissenschaftlichen Grundlagen der .Analyti.schen Chemie,

W. (Jstwald, 482 ; the P'reezing Point of Dilute Solution, 617
Rodway (James), In the Guiana Forest, 387
Roger (H.), Action of High Pressure on Bacteria, 168
Kolleston (H. D. ) and A. \. Kanthack, Manual of Practical

Morbid Anatomy, 318
Romanes (Dr. G. [.), Longevity and Death, 381
Romburgh (Dr. P. van). Volatile Constituents of Coci Leaves,

408 : Nitro-Derivatives of Dimethylaniline, 624 ; Addition

Products of Symmetrical Trinitrobenzol, 624
Rondelet's Rule for Wootlsand End-loaded Beams, C. Maltezos,

622
Roozeboom (Bakhuis), Behaviour of Hydrogen to Palladium at

Various Temperatures and Pressures, 624
Roscoe (Sir H. E. , F. R.S. ), a Treatise on Chemistry, M. M.

I'altison Muir, 193
r isfnstiehl (.V. ), .Moniodamnionium Derivatives of Hexa-

iiiethyltriamidotriphenylmethane, 384
Rose, the Book of the. Rev. A. Foster-Melliar, 362
Roses, Sawer's Rhodologia, 39
Roszel (M. ), the Ma-ss of the .\steroids, 373
Rotation, the .'Mleged Absoluteness of Motions of. Prof. A. G.

Greenhill, K.R.S., 105; A. E. H. Love, F.R.S., 105, 153,

19S; A. B. Basset, F.R.S., 271; Prof. Oliver J. Lodge,

F, R..S., 272
Rotation of Venus, the, M. Flammarion, 21
Rotch (\. L.), the Meteorological Services of South America,

45

Rothert (Dr. W.), Heliotropism, 84

Rothpletz _(.\.), (ieotektonische Probleme, 313

Rouville (Etienne dc). Genesis of Intestinal Epithelium, 288

Royal Horticultural Society, 281

Royal Meteorological Society, 119, 215, 311, 527, 621

Royal Microscopical Society, 95, 191, 335

Royal School of Mines, Pala;ontolog)' at the, Right Hon.
T. II. Huxley, F. R.S., 223

Royal Society, 35, 93, 142, 2 14, 238, 334, 452. 477. 526,
55°- 573- 599. 620; .Anniversary .Meeting of the, 132 : .Ad-
dress by I-ord Kelvin, 133 ; .Medals awarded by the, 136

Rubens (Dr.), Distance-Telegraphy without Wires, 190

Riicker (Prof A. W. , F. R..S. ), the Work of Hermann von
Helmholtz, 44, 472, 493 ; Objective Reality of Combination
Tones, 550

Uuficr (Dr. .M. .\. ), the Treatment of Diphtheria by Anti-To.\ic
-Serum, 16

Kunge (Herr), Prof. V. Pechman, and a New Series of Nitrogen
Compounds, 1 14

Rus.sell (II. C), the Travels of Three Bottle- Palmers, 35

Russia, Catalogtie of Earthquakes in. Prof. Mushkeloff and A.
Orloflr, 181

Russia, Recent Exact Levelling Operations in. General Venukoff,

359
Russian .Astronomical Observations, 207
Russian Chemical and Physical Society, Journal of, 452
Ruwenzori, Exploration at, G. F. .Scott Elliot, 271
Ruvvenzori, Mount, the Glaciati(m of, Scott Elliot, 441
Ryder (Prof. J. .\.), Death of, 587
Ryves (Rev. G. T.), the Recent Drought in the Midlands, 23

Sabatier (Paul), Action of Nitrous Oxide on Metals and Metallic

Oxides, 528 •"-

Safety Explosives in Mines, the Use of, 184
St. Louis Children, the Growth of, William Towns< n<l I'ortt r.

Prof. Karl Pearson, 145
St. I'elersburg Academy of Sciences, 279
St. Pelersbourg, Bulletin de I'.Acadcmie Royale de, 477
St. Petersburg Society of Naturalists, Journal of, 500
St. Petersburg University, the New laboratory at, 392
.Salts, Tables an<l Directions for the Qualitative Chemical

Analysis of Moderately Complex .Mixtures 1 if, M. M. I'ailisi.n

Muir, 270
Samoyad Race, the, -Arthur Montefiore, 279
.Sand-Bla.st, Applications of the, J. G. Holtzapft'el, 5SS
.Sanderson (Prof. J. Burdon, F. R..S. ), Electrophysiologic, Prof.

W. Bicdermann, 553
Sandwich Islands, Rainfall of, Dr. J. Hann, 500
Sanitation : Dc.ith of Mr. E. Turner, 513
Sankcy (Captain H. R.), the Metric System, 562; Vibration o

Steamers, 570
Sap, the Ascent of, H. H. Dixon and Dr. J. Joly, F.R.S., 93
Saporta (Marquis de). Death of, 370
Sargent (Prof. C. S.), Forest Preservation, 380
Saussure (Rene de). Graphical ThernnHlynamics, 334
Savory (Sir William, F. R..S. ), Death of, 440
Sawer (J. C. ), Rhodologia, 39

.Schaberle ( Prof. ), a Possible New Satellite of Neptune, 542
Schenck (Dr. H.), I^-hrbuch der Botanik, Drs. E. Strasburgcr,

F. Noll, and .A. F. W. Schimper, 339
Schenkling-Prevot (Herr), the Tongue and Hyoid Apparatus of

Birds, 252
Schiaparelli (G.), on Mars, Pro.''. W. H. Pickering, 87 ; Mars in

1894, 395

Schift (Prof.), Ammonium Thio-.Acctate as Substitute for Sul-
phuretted Hydrogen, 373

Schimper (Dr. A. F. W. ), Lehrbuch der Botanik, Drs. E. Strr.s-
burger. F. Noll, and H. Schenck, 339

Schinz ( 1 lans), Conspectus Flor.-e .Africa;, ou Enumeration des
Plantes d'Afrique, 459

Schlafli (Prof Ludwig), Death of, 538

Schlick (Otto), Vibration of Steamers, 569

Schlundl (H.), Speed of Liberation of Iodine in Mixed SoIuticn.s,
346

Schliitzenberger (P.), the Atomic Weight of Cerium, 552

.Schmidt (Emil), Reise nach Siidindien, lOI

.Schmidt (Dr.), a Pure White DiSulphide of Tin, 85

Schmitz ( Dr. F. ), Death of, 392

Schneider (Prof.), Re<letermination of .Atomic Weight of Bis-
muth, 131

Schiinland (J.), Snake Cannilialism. 511

.Schools, Geometry in, Edward M. Langley, 176

Schools, Science Teaching in, W. B. Crump, Grace Heath, 56 :
O. Henrici, 106; H. G. Wells, 106

Schorlemmer (C. ), a Treatise on Chemistr)-, M. M. P.-illison
Muir, 193 ; the Rise and Fall of Organic Chemistry, 317

Schrdter (Or. Jo.sef), Death of, 251

Schumann's (Dr. Victor) Vacuum S|wctrograph, 423

Schuster (Prof. Arthur, F.R.S.), the Kinetic Theory of Gases,

293

Schwalbe (Dr. ), Endeavours to Utilise for Scientific Purposes
the Curves of- Temperature obtained from the "Uranus"
Pillars, 72

Schwarz ( Dr. L. ), Death of, 1 1 1

.Science : Science in the Magazines, 44, 161, 259, 380, 450, 545 ;
Science Teaching in .Schools, W. B. Crump, Grace Heath; 56 ;
O. Henrici, 106 ; H. G. Wells. 106: Endowment for Scientific
Research and Publication, .Addison Brown. 164. 1S6 : Science
am! History, .Alfred II. Hulh, 176: Scientific Investigation m
Canada, Dr. G. M. Dawson, F. R.S., 236: Italian Scientific
Ex|)e<lition.to Monte Rosa, Dr. Piero Gi.icosa, 57

Scotland : Scientific Investigation of Scottish Fishery B<iard,
115 ; the Starling in, J. II. Harvic-Brown, 280: Mussel Cul-
ture and the Bait Supply, with reference more es|x.Ti.illy to
Scotland, W. L. Calderw< o<l, 578 ; Scottish .Meteorological
Sixiely, 542, 621

Scott (Charlotte Angas), an Intro<iuctory .Account of certain
Mo<lern Ideas and .\Ietho<ls in Plane .Analytical Geometry,

483 .
Scott (Dr. D. H., F.R.S,), Fossil Plants of Coal -Mea.su res, II.,

the Roots of Calamiles, 94

Scott (D. II.), Obituary No'icc of N.athan.tel Pringshcim, 399

XXXll

Index

upflement to Xatnrf,
May 30, 1895

Scott-Moncrieff(Sir Colin), the Nile, 444

Screw Propulsion, the Limitations of, ]. I. Jhornycroft, F. R.S.,
and S. W. Bamaby, 362

Scribner's Magazine, Science in, 44, 381

Sea and Land, Features of Coasts and f)ceans, with Sjiecial
Reference to the Life of Man, N. S. Shaler, 507

Sea-Water, the Methods for Determining Density of, W. S.
Anderson, 61

Sea-Water and Oceanic De]>i>sits, Chemical Changes between,
Dr. John Murray and Robert Ir\ine, 304

.Seasonal Changes on Mars, Mr. IVrcival Lowell, 259

Secular \'ari2iion of Terrestrial Magnetism, Wildes Theory of
the, L. .\. Bauer, 103

Secular Variations of the Interior Planets, Prof. Newoomb, 1S3

Sedgwick (.\dam, F.R.S.). Inadequacy of Cell-Theory, 119,
213; the Development of Nerves, 119, 213

Seeds, the Soaking of. I'. C. (.ilubl), 107

Seeler (Mr.), the Termination of Motor Nerves in Muscles, 288

Segmentation, Vertebrate, P. Chalmers Mitchell, 367

Seiches in Lake Derravaragh, J. II. K. MacKarlane, 502

Seismology: Seismological (ibservalor)- to be Founded at
Constantinople, 180: on a Remarkable Karlhijuake Dis-
turbance ob-served at .Slra.ssliurg, Nicolaiew, and Birmingham,
on June 3, 1S93. C. Davison. Dr. E. von Rc1>eur I'aschwil?.,
20S ; Connection between .\rgentina Karthquake of October
27 and Contemporary F.uro|)ean Pulsation Series ? 232 ; the
Velocity of the .\rgeniine Karthquake Pulsations of October
27, 1894, C. Davison, 462 : the .\lleged Diminution with Out-
.vard Radiation of \'elocity of Farlhciuake Waves, Dr.
Agamennone, 299 ; I)isl.>cation of Sumatra .Mountain .System by
Earthquakes of May 17, 1892, J. J. .\. Muller. 40S ; the -After-
shocks of Earthquakes. F. (Jmori. 423 : the Constaminoi)le
F.arthquake of July lo. 1894. Prof. Cancani. 440 ; Seismic
History- of Calabria Ultra, Dr. Mario Baratta. 468 ; Prof.
Vicentini's New Seismometrograi)h. 540 : the Seismological
Obserx-ator)- Destroyed at Tokio, 585; I'rof. J. W. Judd,
K.R.S., 533 : the Observation of Earth- Waves and Vibrations,
Prof. lohn .Milne, F.R.S., 548

Scnilerens (I. B. f, .\ction of Nitrous Oxide on Metals and
Metallic Oxides, 528

Sergi (Prof. Giuseppe), the Varieties of the Human Species, 595

.Seward (.\. C), Pachytheca, 480

Sewer Air, the Harnil-.-ssne.ss of, Messrs. Laws and Andrewes,

37'
Sexton (A. Humboldt), Elementary Text-Book of Metallurgy,

556
.Shaler (Prof. N. S.), the Horse, 44 : Sea and Land, Features of

Coasts and Oceans, with Sixjcial Reference lo the Life of Man,

507
SI\arp(Dr., F.R.S.), Geographical Distribution of Butterflies,

479
Shaw (J.), Tan-S|X)ts over Dogs Lyes, 33 ; an Aurora on

Novemlier 23, 107
Shaw(W. N., F. R.S. ), Motion and Formation of Clouds, 527
Sheet Lightning, Dr. Meinardus, 192
.Shenslone (|. C. ), Remarkable 0.ak Trees in Ks,sex, 280
Shcrborn (C. Davies), tl.e Life of Sir Richard Owen, 169
Sherrington (Dr. C. H., F. R..S. ), Influence of Sensory Nerves on

Movement in Nutrition of Limbs, 620
.shipbuilding. Wanted :i Subslilule for Wood in, 490
.Short (I^'wis E. ), I'hysiMl.igy for Beginners, 165
Siberia ; Captain Wiggin- Wrecked. 83
Siberia, Baron Toll's Ivxpcdilion, 327

Siberian Railway, Geological Researches in Connection with, 539
Sicily, Earthquake in, 82, 513
Sicilian l-jtrthquakes of August 1894, the. Dr. M. Baralta and

I'rof. Ricco, 207
Sickne.w, Mountain, II. Kronecker, 394
Sieljc (W.), Botanical Kx|iedilion lo .Asia Min.M, 513
.Siemens (.V), Advice I o Voung Engineers, 131
.Sicrtsema (Dr.), Magnetic Rotational DLsjicrsion of Oxygen and

Nitrogen, 504
,Signal», Eflecl of Rhythm on Visibility of, Charles 1 lenry, 588
Silver, Colloidal, C. Barus, 190

Silvering Gla^s, Simplified I'rix-ess for, A. ami L. Lumicrc, 371
.Siinmons(f J. L.), DcvclopmenI of Lungs of .Spiders, 37
.Simroth (11.). KhyuihoJeimis trrinln's m Germany, 294
Singing Water- Pijics, W. B. Croft, 107
Skertchly (S. B. J.), .Suiwrficial De|K).sils of .Shaniung, 478
Skinner (S. ), the Tin Chromic Chloride Cell, 383
Slidc-Kule, the, a Practical Manual, Charles N. I'ickworth, 77

Slingo (W.), Electrical Engineering, 31S : Problems and Solu-
tions in Elementary Electricity and .M.agnetism, 580

Smellie (Sir William) and his Contemporaries, John Gliiister,
149

Smith (C. S.), the Anglo-German Frontier Survey in East Africa,

Smith's (Dr. Donaldson) Expedition to Lake Rudolf, 61

Smith (Prof. E. F. ). the .\lomic Weight and Specific Heat of

Tungsten, 424
Smith (G. Elliott), the Cerebral Commissures of the Mammalia,

192
Smith (Dr. lohn), a Peculiarilv in the Mammalian Tooth, 215
Smith (J. C'., P.Inst. C.E., Ireland), De.alh of, 4.SS
Smith (Robert H.), Me.isurement Conversion Diagrams, 221
Smith (Worlhinglon G.). Spots over Dog's Eyes, 57 : .Man — the

Primeval Savage. Prof. \V. Boyd Daw kins, F. R.S. , 194
Smithsonian Institution, Report for 1S94, 571
Snail Fauna of the Greater .\ntilles. the, 524
Snake-Poison, Strjchnine no Antidote to, Surgeon-Captain R. H.

Elliott, 540
Snakes : the Swallowing of one Snake by another. Baron C. R.

O.sten Sacken, 12: Snake Cannibalism. II. Tsnagal, 321;

Baron C. R. Osten.S.icken, 343; J. Schonland. 511 ; Snakes

" Playing 'Posiium.'' L. C. Jones, 107; li. E. Hadow. 127;

Death-feigning in Snakes, tlerard W. Butler, 153: the
Feigning of Death, R. Harry \'incenl, 223 : the Suspended

Animation of Snakes, S. (iarman, 274 ; W. Kennedy, 274
Sodium and Potassium Derivatives of Nitromethane, the Explo-
sive Nature of the. .\. E. Tullon. 32S
Solar M.ignetism in Meteorologv. I'rof. F. H. Bigelow, 356
Sollas (I'rof. W. J., F.R.S.), the .\ge of the Earth, 533, 55S
Solowel/.k Marine Biological Statiim, S3
Solute, F. G. Donnan, 200

Sohvay, the Natural History of the, C'l. Stewardson Brady, 322
Somerville (I'rof. W.), the .\nbury Turnip Disease, 251
Sorauer (Dr. I'aul), a Pojiular Treatise on the Physiology 01

Plants, 554
Sound : Singing Water-Pipes, W. B. Croft, 107
Sound, a Text-Book of, E. Catchpool, 244
Southall (H.), FUhmIs in ihe Wesi Miillamls, 21$
1 Species, New Lawof Geographical Distribution of, Chas. Dixon,

545 . .

Specific He.ats of ti.ases, the Ratio ol

127
Specific Stability, \ ariationand, W . I

459

Specific Stability, (Questions Bearing
F.R.S., 570

Spectrum .Analysis : the Spectrum of S Cephei, M. .\. Kelo-
polsky, 21 ; Studies of Bunsen Flame .Spectra of AlUalin and
Alkaline Earth Metals, Eder and \alenta, 20: on Recenl
Researches in the Infra-Red Spectrum, I'rof. S. P.. Langley.
12 ; an .Artificial Spectrum Top, C. E. Benhani, 113. 200,
321 : Prof i\. 1). Liveing, F.R.S., 167. 200 : CaiXain W. de
W. .Abney, C. B., I'.R.S., 292 ; J. M. Finnegan B. Moore,
292; Dr. F. W. Edridge-Green, 321 : Dr. Dawson Turner,
438; Newton and Co., 463; a True Spectrum Top .and a
Complementary one. Dr. C. Herbert llursl. 510: the Spec-
trum of Mars, Prof W. W. Campbell. 132: the Blue C,rotlo
of Capri Speclroscopically Tested, Dr. II. W. \'ogel, 300 :
Stars having Peculiar Spectra, I'rof. V.. C. Pickering, 302 :
Method of Rotating Prism, F. L. O. Wadsworth. 325; New
Spectrum Photomeler, Arthur Kiinig. 334: on the Spectra of
Argon, William Crookes, F.R.S.. 354 : H. F. Newall, 454;
the Spectra of Argon and of .Aurora Borealis, M. Berthclot,
552; Fluorescence Spectrum of Argon, M. Berthelot, 622;
Dr. Schumann's Vacuum Spectrograph, 423; .Spectroscopic
Me.-isures of Planetary \'clocilies, .M. Deslandres, 443; Ob-
.servations on SunSpol Spectra, J. Norman Lockyer, F.R.S.,
448; Spectrum of lliu Orion Nebula, 471 ; Sped rum. if Terrestrial
Helium (?), i'rof Ramsay. 543 : W. Crookes, I". R.S., 543 ;
Terrestrial lleliuni(?). Prof Ramsay, 543; W. Crookes, 543 ;
I. Norman Lockyer, C.B., F. R.S., 5.S6 ; Pos.sible Exi)lanation
of Tw<ifol(l Spectra of (Jxygen and Nitrogen, !•;. C. C. Baly,
550: Ihe .Sun's Place in Nature, J. Norman Lockyer, C.B.,
F'.R.S., 374, 396, 565, 590 : I'ltra \iolel Radiation of Solar
Corona (luring Total lOclipse of .April 16, I,Sg3. II. Dcslandres,
576; the l'ltra-\'iolel Spectrum of IheCorona, M. Dcslandres,
589; Ihe Fluted Spectrum, II. Poincare, 599

Spelivologie, StKitte de, l-'ounded. 229

Spela;ology, the Society of, Mark Stirrup. 462

, S. II. Burbuiy. F.R.S.,
. Thiselton-Dyer F.R.S.,
Dr. l'"rancis Gallitn.

Supplement to Xatitrt ~|
May 30, 1895 J

Index

XXXIll

Sjiencer (^^r. ), Enargite, 621

Spencer ( I'rof. Baldwin), the Horn Expedition to Central Aus-
iralia, 222 ; the Presence of a Stridiilaling Organ in a Spider,

438

Spencer (Herbert), Origin of Classes among the "Tarasol"
Ants, 125

Spheres, Method of Turning True. Herr Vf)n Liechtenstein, 491

S])iders : Development of Lungs of, O. L. Simmons, 37 ;
Malaysian Spiders, Thos. and M. K. Workman, K. L I'ocock,
99; Indo-Malayan S])iders, H. A. Muirliead. 153: some Sug-
gestions on the Origin and Involution of \Vel>-Spinning in
Sjjiders, R. L Pocock, 417 : the Presence of a Stridulaling
Organ in a Spider, Prof. Baldwin Spencer, 438: .Vmerican
Spiders and their Spinning Work. Dr. Henry C. McCook,
Rev. O. P. Cambridge, F. R.S., 505

Sponges, American Kresh-Water, in Ireland, Dr. R. Hanitsch,

5"
.Sportsman and Naturalist, Sir Victor Brooke, O. L. .Stephen.

.Spots over Dogs' Lyes, Wfirthington (_f. Smith, 57

Spots, Tan, over Dogs' Eyes, 1. Shaw, 33 ; S. V.. Peal, 533 :

Dr. Alfred R. Wallace. K.K..S., 533
.Spr.tgue (Is.iac), Death of, 538
Spring to Kail, from, 8
S|)ring (W.), Conversion of Black Mercury Sulphide in'.o Red

Sulphide. 167
Spurr (J. E. ), the Iron-bearing Rocks of Mesabi Range in

Minnesota. 182
^ .tiility, Specific, Variation and, W. T. Thisellon-Dyer, F.R..S.,

.459

Stability, Queiitions l.varing on .Specific, Dr. 1-rancis dalton,
K. R.S., 570

Stalactites, Volc.".nic, E. (loldsmith, 12S

.Standard Time in Austr.alia, 516

.Standards, New Metric, 420

Starling in Scotland, the, ]. j\. Harvic-Hrowu, 2S0

Stars: the .Mean Parallax of Stars, Prof. Hugo (^ylden, 21 ;
Two Variable .Slars, Rev. T. E. Espin, 40 : a New \ariable
Smr of the .\lgol Ty]>e, Dr. E. Harlwig, 64 ; Irregularities in
\ ariable Stars. W. Maxwell Reed, 183 ; the \'ariable .Star
/. Herculis. 616; a New Short Period Variable, Mr. Vendell,
233; Motiimand Magnitude. Prof. Oudemans, 160 ; a New .Star,
Rev. T. E. Espin, 161 : the R.idclifil'c Catalogue. 183 : ! Cephei.
Dr. Belopolsky, 282 ; Stars having Peculiar .Spectra, I'rof.

E. C. Pickering, 302 ; the Milky Way, C. E.aston. 327 : the
System of -Vlgol, .M. Tisserand, 328 ; New Stars and Nebuke,

. 347 ; the Story of the Stars, Ceorge K. Chambers, 436 ;

Stellar I'hotography, 516
Statics, a Text-book of William Briggs and O. II. Bryan,

76
.Statics, Mechanics for College.s and Schools, R. '1. Clazebrook,

E.R.S., 484
Statistical .\ccount of French Forests, .M. Daubree, Prof. W. R.

Fisher, 64
.Statistical Investigation of Evolution, the, J. T. Cunningham,

5'.°.
Statistical Science, a New .Step in, !•. dalton, I.R.S.. 319

Statistics, Dilettantism and, I'rof. Karl Pearson, 145

.Statistics of .Sensil)ility to Pain. Dr. A. .McDonald, 299

Statistics: Death of H. II. Hayter, 513

Steam Engine and other I le.'it Engines, the. Prof. J. .\. Ivwing,

F. R.S., 219

Stcbnitskiy (General), .-Anomaly in Direction of Pendulum Line

around Moscow, 326
.Steinlrach's (Dr.), Observations on the Climate of Jalu, Prof.

Von Danckelniann, 192 ; Meteorological Researches at Jaluit

Islai.d, 233
.Stellar Parallaxes, T. Lewis, 589
Stellar Photography, 516

Step (Edward), By \'ocal Woods and Waters, 102
Stephen ((J. L. ), Sir Victor Brooke, Sportsman and Naturali.st,

'ilcreochemie, Handbuch der. Dr. C. \. Bischoft, 409

Stern (A. L. ), Cellulose Sulphuric Acid, 143

■itev.'nson (Thomas), a Treatise on Hygiene and Public Health,

124
stieUjes (Prof), Death of, 251

Stirling (Dr. li. C. ), the .Aboriginesof .Viistralia, 112
■itirrup (.Mark), the Society of Spekeology, 462
v.okes (H. N.), New Compounds (jf Phosphorus, Nitrogen .and

Chlorine, 592

Stones, Precious, and How to Distinguish them, H. A. Miers,

54S
.Stoney (Dr. [., 1-.K..S.), Local Heliostat and Improved Sider-

ostat, yx>
Storm, the Recent, in the Cnited States, Dr. Wm. H. Hale,

4"7
.Storm .Statistics at Bidston, W illiam E. Plummcr, 272
Siracciati (I'rof. E. ), Determinations of Absorption of Solar
I Radiation by Fog and Cirrus Cloud. 180
Str.asburger (Dr. E. ), Lehrbuch der Botanik, Drs. F. Noil, H.

Schenck. and .\. F. W. Schimper, 339
Strassburg, Nicolaiew , and Binninghani, on a Remarkable Ear.h-

quake Disturljance observed at, on June 3, 1893, C. Davistjn,

Dr. E. von Rebeur Pa.sch«it/., 208
Slreinz (Franz), Thermochemical Pr<x:ess in Secondary Coils, 190
.Stridulating Organ in a Spider, the Presence of a, Prof. Baldwin

.Spencer. 438
Stronieyer (C. Y.. ), .\bnornial .\tlantic WVives, 437
Struve (Herr), Compound of Grape Sugar with Add Radicle of

Hydrazine, 395
.Strychnine no .Antidote to Snake-Poison, Surgeon-Captain

R. H. lilliott, 540
Stuart (Dimald, M.D.), Coal-Dust an Explosive Agent, as shown

by an Examination of the Camerton Explosion, 26S
Stuckenberg (Prof.), the Post-Pliocene -Mammalsof East RussLa,

357
Studiati (Dr. C), Death of, 251
.Study (Prof. E. ), the Connection between Binary Quartics ami

Elliptic F'unctions, 46
.Subterranean Exploration ; Socicte de Spelxologie founded, 229
.SiidiiKiien, Rcise nach, Emil Schmidt, loi
.Sulphur- Fumigation, as Remedy for Mar.sh Fevers, M. d'Abbadic,

480
Sumatra Mountain System, Dislocation by Earthquakes of May

17, 1892, of, [. J. .\. Muller. 408
Sun, Partial Eclipse of the, March 26, 493
Sun's Place in Nature, the, J. Norman Lockyer, C.B., F.R.S.,

374- 396. 565- 590
Suns, Radiant, .Agnes Giberne, 174
.Sun-.Spots : Eleven-year Sun-S|xit Weather Period and its

Multiples, H. Helm Clayton. 436 ; OViscrvations on Sun-Spot

Spectra, J. Norman Lockyer. F. R..S. , 448
Sunshine, Rain-Making and, John Collinson, 7
.Surgery : Death and (Obituary Notice of John Whitaker Hulke,

F.R..S.,392
.Surinam Water-Toads, the, 230
Suring (Dr. ), OKservalions on Temperature Humidity near Snow

Surface, 623
Surveying, the Gradient Telemeter Level, 112
Surveying by -Mil of Photography, Instrument for, J. B. 'Lee,

'9' . .

Surveying : Recent Exact Levelling Operations m Russia,

General Venukofl", 359
Suspended .Xnimation of Snakes, the, .S. Garman, 274; W.

Kennedy. 274
.Swainson (F. E. ), New Ossiferous Fissure jn Crcswell Crags,

527
.Swallow- Holes, Caves and, E. .\. Martel. Canon T. G. Bonnoy,

F. R.S.. 410
Sweat. Efl'ect of Temiwrature on Secretion of. Dr. Le\-y-Dotu,

192
Swift (Edwiird), a New Comet, 1 14: Ephemeris for Swift's

Comet, 160: Comet r 1894, Swift, 542
.Swift (Messrs.), New Microtome, 191
.Swinburne ({.), Electromagnetic Theory, Oliver Heavisidc.

F.R.S., 171
Symons's .Mcmlhly Meteorological Magazine, 23, 525
Symons (G. J.), Early English .Meteorological Literature, 38;

Enormous Hailstones, 24 ; Climatological Table of British

F2mpire for 1893, ^4
.Szomlathy (J.), Prehistoric Ceramics from L.ingcnlebarn

Tumulus, 157

Tacchini (Prof.), the South Italian Earthqu.-ike of November 16,

1894, 346
Tail (Prof), the Constitution of X'olatile Li(|uids, 215 : Iso-

ihermals of Ethylene. 215 ; on the .Age of the Earth, 226
Tanret (C. ), .\cetic lathers from Sugars, 359
Tan-Spots over Dogs" Eves, I. Shaw, ^i; S. E. Peal, 533 ; Dr

Alfred Wallace, F.R.S., 533

XXXIV

Index

VStijtpictitent to Xat:ifr,
L May 30, 1895

Tansley (A. G.), Variations in Floral S)Tnmetry of Polentilla
tormmtiiiay 359

Tarns of Lakeland, the. J. K. Marr. F.U.S., 190

Tanigi (Dr.), Ammonium Thio-acetate a Subsiituie lor Sul-
phuretted Hydrogen, 373

TnliT (F. B.), Niagara and the Great Lakes, 619

I ;> wrt. Bright Meteor at, 587

1. hel>itchef {I'afnutijl, Death of, 180

Technical Education: Fifth Kejiort of ( German Imperial I'liysico-
Technical Institute, 20 : the New Technical Educator, vol. iv. ,
S3 ; .Major-General Sir John Donnelly, on Technical
Education, 116: .Science Teaching, H. G. Wells, 182; the
Advance of Technical Education, k. .\. Gregory, 379

Teinturier, la I'ratique du, Jules Garden, Walter .M. Gardner,
604

Telegraphy : Distance-Telegraphy w ithoul Wires, Dr. Rubens,
190: the Development of Telegraphy in England, 324 ; the
Telegraphist's Guide, James Bell, 484: Death of J. H.
Greener, 561 ; W. II. I'reece (P". R.S. ), .Method of Telegraphy
l>y Induction, 587

Telephone Communication opened between \iciina and Berlin,
129

Telephony, the EJirly History of, Prof. D. E. Hughes, F. R.S.,

54'
Telescope, a New Form of Zenith, M. Louis Pabry, 564
TellenlK-rg (Dr. E. de), EiKene at .Murren (Correction of Sir

John Lubtjock, p. 94), 180
Tem|)erature \ariations of Rivers of Central Europe, Dr. A. K.

Forster, 83
Tem|)eratures, Oceanic, at Different Depths, Capt. W. J. L.

Wharton, F. R.S., 342
Teppich-erzeugtmg ini Orient, 77
Terre.strial Helium (?), 512 : I'rof Ramsav, 543 ; W. Crookes,

F.R..S.,543; J. Norman U>ckyer, C.B.,'F.R.S., 586
Terrestrial .Magnetic Discoveries pertaining to England, some

Early. Will Whislon, L. A. Bauer, 295
Terrestrial Magnetism, Wilde's Theory of the Secular Variation

of, L. .\. Bauer, 103
Text-books, a Bad .Metho<l in, Dr. E. Ray Lankester, F.R.S.,

2S9
Theophr.istus of Eresus, on Winds and on Weather .Signs,

translated by Ja.s. G. Wood, 25
Therapeutics : the .\nti-Toxin Treatment of Diphtheria in

France, 83 ; .Statistics of Results of Behring and Roux's

Treatment of Diphtheria, 324; .Advantage of High-Level

Residence for Tuberculous Patients, Dr. A. C. Miller, 370 ;

Sulphur-Kumigation as Remedy for Marsh-Fever, M.

d'.\bliadie, 480 : Thera|ieutic .Xction of Currents of High

Frccjuency, .\postoli and Berlioz, 528 ; Intense Cold a.s a

Therapeutic Application, Dr. Pictet, 588
Thermodynamics: the Kinetic Theor)- of Ga.ses, G. H. Bryan,

31, 152, 176, 319; Edward I', Culverwell, 78, 58: Dr. J.

Termor, F. R.S., 152; S. II. Burbury, FR.S., 175: I'rof.

{;. F. Fitzgerald, F.R.S., 221 ; Rev. H. W. Watson, F.R.S.,

222; I'rof. A. Schuster, F.R.S., 293; Prof. Boltzmann, 581 ;

Theoretical Chemistry from the .Standpoint of Avogadro's

Rule, and Thernnxlynamics, Pr<jf. Walter Nernst, M. M.

Patlison .\luir, 530
Thermometer, the I'irsl .Mercury, used by Ismael Bouilliau,

Ablx; Maze, 576
Thirst-I'ndurance in some Vertebrates, Prof. S. Garman, 343
Thisclton-Dycr (W. T., F.R.S.), Dr. Watt's Dictionary of the

Kconomic PhkIucIs of India, 150; the New Cypress of

Ny.xsaland, 175 : Variation and Specific .Slabilily, 459
Tliomas (I..), the Coi\slilulion of the Electric .\rc, 47
1'homa.s (\'.), Combinations of Nitric Oxide and Iron Chlorides,

4SS
ThomiKon (Prof. S, P.), Mirrors of Magnetism, 142
Thomson (Prof. J. J.), Electric Discharges through Ga.scs, 330 ;

Mciho'l of Determining Conductivities of Itadly-Conducting

•^. 43>

Dr. Murray), Death of, 298

I. T. E. , K. R.S. ), the Explosion of a .Mixture of

an<l Oxygen, 106
' y of Lukchun Deprcssi.-in, M. Roliorov.sky, 491
I iinlier, l-.x|x:rimcnts on Strength of C.inadian, Dr. II. H-jvey,

492
Timln-r Trees, the Planting of, .Mfretl W. Bennett, 33
Time, Standard, in .\ustralia, 516

Ti'.wrand (M.), the Sy.slem of Algol, 328; the Variable S:ar i9
(.\lgol) in Perseus, 336; an Important Asteroid, 254

Tissot (J.), Relative Signification of Disengagement of Carbonic
.\c\A and Absorption of Oxygen by Muscles, 503

Tobacco-Pipes, Cleaning, Cecil Carus-Wilson, 511

Todd (SirC F. R..S. ), Meteorological Work in .Vu.stralia, 3^5

Tokio, Earthquake of June 24. 1S94, the, 563

Tokio, the Seismological Observalorv Destroyed at, 585; Pr< f.
>. W. Judd, F.R.S., 533

Toll's (Baron) Siberian Expedition, 327

Tooth, a Peculiarity in the Mammalian, Dr. John Smith, 215

Top, an Artificial S|>ectrum, C. E. Benh.im, 113, 200. 321 ;
Prof. G. D. Liveing, F.R.S., 167, 200: Capt. W. de W.
.■\bney, F.R.S., 292; J. M. F. B. Moore, 292; Dr. F. W.
Edridge-CJreen, 321 ; Dr. Dawson Turner, 438; Newton and
Co., 463

Top, aTrueSpectnim.and a Complementary one. Dr. C. Herbert
Hurst, 510

Toixjgraphy, American, Prof Henry Gannett, .\. Fowler, 274

Tornado m Oregon, 19

Toronto Magnetic Observatory, 237

Total Eclipse, by Order of the Sun to Chile to s;e his, April 16,
1893, J. J. Aubertin, loi

Towns, the Water-Supply of, W. K. Burton, 146

Toxicology : the PeyotI (^ctus Alkaloid, Prof. L. Lewin,
288 ; .Strychnine no .Xntidote to Snake-Poison, -Surg. -Captain
R. H. F:iliott, 590

Transit of Mercury, 40 ; Observations of the, 85, 253

Trawling (,)uestion, the. Prof. .Mcintosh, 115

Trees, (Contraction of, caused by Cold, J. Clayton, 462

Trees : the New Cypress of Nyasaland, 85

Trees, Text-Book of the Diseases of, Prof. R. Harlig, I'rof. \V.
R. Fisher, 28

Trees, the Planting of Timljer, .\lfred W. Bennett, ^^

Trematodes of Jajxin, Studies on the Kcloparasitic, Seitaro Goto,
244

Tretjakow (M.), Polyembryony, 540

Trevor- Battye (A.), Return of, 19 ; Visit to Kolguef Island, 36

Trinucleus, C. F. Beecher, 619

Tsnagal(H.), .Snake Canniljalism, 321

Tuberculous Germs possessed of Locomotive Power, D. Mac-
Gillivray, 623

Tuberculous Patients, .\dvantage of High-Level Residence for,
Dr. A. C. Miller, 370

Tuke (Dr. D. H.), Death of, 440

Tumbling Cat, M. Marey's Photographs of a. So

Tunis, the Metric .Sy.stem in, 324

Turner, Dr. Dawson, the Spectrum Top, 43S

Turner (E.), Death of, 513

Turner (J. H. Tudsbery), the Principles of Waterworks Iji-
gineering, \. W. Brightmore, 146

Turner (Sir W. ), Duboison Pithecanlhropoid Remains in Jav;i, 6ig

Turnip Disease, the Anbury, I'rof. N. .Somcrville, 251

Tusayan Indians, the " New Fire" Ceremony among the, J. W.
Fewkcs, 515

Tutton (.\. E.), the Properties of Liquid Ethane and Pro|iane,
65 ; Prof Victor Meyer's New Method of Determining High
Melting-Points, 161 ; a New Element in the Nitrogen Grou|i,
258; the Explosive Nature of the SodiuuK'.nd Potassium Deriva-
livsof Nitromelhane, 328 ; an Instrument for Cutting .Section-
Pl.atesand Prismsof Crystals, 452 ; New Conii>ounds of Hydra-
zinc with Fatly Acids, 516; Isolation of Free Hydrazine
N.JH4, M. Lol)ry de Bruyn, 544 : an Improved Method for
the Microscopic Investig.ition of Crystals, 608

Ty|>hoid, Oysters ami, 391 ; Mrs. Percy Frankland, 415

Typhoons of China .Seas, 1893, the, 130

Uljanin (Dr. W. von), PoKarisation by Oblique Radiation, 623
Ultra-Violel Spectrum of the Corona, the, M. Deslandres, 589
Unification of Civil and /Vslronomical Days, the, 282
United States: the .Misorption of the In(lian Reservalions, 19 ;
Re|)ort of United States Weather Bureau for 1893, 39 ;
Biolog)' in the, a Prospect, 81 ; Fox-Tail Grass- I'est in the
I'ttited .Stales, 301 ; the Recent .Storm in tin-. Dr. Wni. II.
Hale, 417; American Spiders and Iheir Spinning Wi>rk, a
Natural Hislory of the Orb-Weavhig .Spiders of the United
Slates, with special regard 10 their Industry and Habits, Dr.
Henry C. McCook, Rev. O. P. Cambridge, E.R.S., 505;
Uniteil Stales Units of Electrical Measure, ihe, 518
University College, the New Physical Labiiralories of, 298
Univer.sity Intelligence, 23, 45, '70, 92, 141. 261, 287, 308, HJ,,

356, 382, 406, 429. 45'- 477. 499. 5^5. 57^. 59«. biy
University of London, a True, M. Crackenthorpe, i6i

SuppUmtnt to S'aturt,~\
May y>, 1895 J

Index

XXXV

University for Lfimlon, the' Teaching, Dr. W. r'alnicr Wynne,
297

Unwin (rrof. William Cawlhornt, K.K.S.), on the Develop-
ment anil Transmission of Power, 124; the Determination of
tile Dryness of Steam, 377

Upham (Warren), I-ate (llacial or Champlain Subsidence and
Reelevalion of St. I.awrence River Hasin, 333

1 I ^:da Meeting of the International Meteorological Committee,
the, 185

Upton (I'nif W. ). Cyclonic Precipitation in New England, 142

Vaccination Question, the, Arthur Wollxston Ilutlon. 149

Valency ? What docs the Chemist Mean hy, 409

Vaknia (1).), .Mudies of Hunsen Flame Spectra of .\lkali and

.'\lkaline Karth .Metals, 20
Varet (Kaoul), Researches on Mercuric Sulphates, 24; Re-
searches on .Mercurial Nitrates, 72 ; Isomeric States of 0.\idcs
of .Mercury, 528
Variable .Spots, Lunar River Beds and. Prof W. IT. Pickering, 589
Variable Stars: Two Variable Stars, Rev. T. K. Kspin, 40 ; a
New Variable- Star of the .Algol Type, Dr. K. Ilartwig, 64;
Irregularities in \'arial)le Stars, W. .Maxwell Reed, 1S3 ; a
New Short Period \ariable, ilr. Vendell, 233 ; S Cephei, Dr.
Helopolsky, 282 ; the System of .Mgol, .\I. Tisserand, 32S :
the \ariable Star Z Herculis, 616
Variation in Animals and Plants, Prof W, F. K. Weldon.

F. R.S., 449
\'arialion, I-",x|K"riniental In(|uir)' into Causes of, H. .M. X'ernon.

454
Variation of l,alilude, the. 373
\'arlation and .Specific Stability, W. J. Thiselton-Dyer, F. R.S..

459
Varialion of Terrestrial Magnetism, Wilde's Theory of the

Secular, L. .\. Bauer, 103
Varieties of the Human .Species, the. Prof (liuseppe Sergi, 595
V.aschy (.M.), I'.leclroslatic Capacity of Line Traversed by

Current, 240
Vatican Observatory, the, 282
Vaudin (L. ), Calcium Phosphate of Milk, 600
Veedcr(Dr. .M. -V.), Twelve- Vear Intervals in Ri.se and Fall of

Tem])erature. 513
Veley (W. IL), .\ction of Hydrogen Chloride on (Juicklinu-.

-Magnesia, and IJaryla, 311
Wdoeilj- of the .\rgenline Farthciuake Puls:itions of October 27.

1S94, the, C. Davison, 462
Venukolf((;eneral), Recent Exact Levelling Operations in Ru.s.sia,

.359

\ emi^. the Rotation of. ,M, Mammarion, 21

Vermin, Helpful and Harmful Farm, 174

Vernon (11. M.), Eflect of Environment on Development of

Echinoderm Larva;, 454
VerschatTelt (Dr.), Vapour Tension and Hygrometric States, 167
Vertebrate Segmentation, P. Chalmers Mitchell, 367
\'crtebrates, Thirst-Endurance in some. Prof. .S. Carman, 343
Vertebrates, .Xmphioxus and the Ancestry of the, .\rlluir Willey,

433
Verworn (Prof Max), Modern Physiology. 58; .\llgemeine

I'liysioloiric. Dr. .M. Foster, F.R.S., 529
\'ibralions, llie Oliservalion of Earth-Waves and, I'rof |ohn

.Milne, F.R.S., 548
Vicentini's (Prof) New Seismometrograph, 540
Vienna, Earlhcpiake at, I lO
Vienna and Herlin. Telephone Communication opened between,

129
Vigouroiix (M.), Preparation of Amorphous Silicon, 312; on the

I'rojKTlies of .\morphous Silicon, 432
\'illeniontee (C. C. de). Electric Potentials in Liipiid Conductor

in flniform .Movement, 240
Villiers (A.), (Jualitative Separation of Nickel and Cobalt, 288
Vincent (II.), the Disinfectiim of Frecal Matter by Copper

Sulphate, 16S
Vincent (R. Harry), the Feigning of Death in -Snakes. 223
Vincenliiii (C.), the Transmission of Electricity through (Jases.

5>4
Vine, Fertilising Materials recpiired by, \. .Miinlz, 480
Violle(|.). Teiiipeniture of Electric .\rc, 16S
\'ilicullure, Fertilisitig .Materials reipiired by Vine. .\. Miintz,

480
Vocal Woods an<l Waters, by, Edward .Step, 102
V<igel (Prof. II. W.). Effects of Mimochiomalic Light on Series

of Pigments, 191 ; the Blue (Irotlo of Capri .S|>eclro.scopic-

ally Tested, 300 ; Ex|)eriments on Colour-Sensation, 469
Volcanic Rocks, Induced .Magnetism in, (J. Folgherailer, 617
Volcanic Stalactites, E. Cloldsmilh. 128
N'olcanoes : Study of Ejected lilocks frcmi .Mount Somma. Proi.

Johnston-I^vis and Dr. J. W. (Gregory, 251
Volkmann (P.), -Mea-surement of Surface Tension of Water in

Capillary Tubes, 190
X'oltameter, New Cas, Mr. Naber, 500
\ uillemin (Paul), Microsporon, 503

Waals (M. van der). Condition for Equilibrium l>eiween Co-
existent Phases, 504

WadsHiirlli (F. L. O.), New Interrui)ler for I«arge Induction
Coils, 190; .MethotI of Rotating Prism in Speclnnn -Analysis
,325

Wagner (Woldemar), L'Industrie des Arancina, 363

Walcott (C. D.), .-\ppalachian Type of Folding, 525

Walileyer (I'rof), Formative Structures of Nervous System. 312

Wales, Agricultural Field Experiments in, 614

Walford (E. .\.), Lias Ironstone round Banbury, 35S

Walker (J.), Electrolysis of Pota-ssium .\llo-ethyiic Camphorate,
621

Walker (Louisa), Varied Occupations in Weaving, 435

Walker (.Miles), Mirrors of Magnetism, 142

Wall.ace (Dr. .\lfred R., F.R.S.), Reason of Failure of Bateson's
and (;allon"s Theories of Organic Evolution. 450 ; Tan-S|x)ts
over Dogs' Eyes, 533 ; the Age of the i:arth, 607

Walther (Prof Johannes), Die Lel>ensweise iler Meereslhiere,
269 ; Lithogenesis derClegcnwart, 313

Warble Fly, the, W. F. Kirby, 154

Warliurg (E. ), Conduction and Convection in Feebly Conducting
Dilute Solutions, 619

Ward (R. deC. I, Recent Russian Stu<lies of Thunderstorms, 451

Warington ( Prof R., F. R. S. ), .Agricultural Art and Science, 372

Warth (Dr. H.), the Quarrjing of (iranite in India, 272

Washington (II. .S.), .Vventurine Clas-s, 112

Watchmaking : Manufacture of .Standard Screws for .Machine-
made Watches, C. I- Hewitt, 22

Water : Redelermiitation of Tenii>erature of (ireatC-st Density of,
.M. de Coppet, 37 ; the Electric Conductivity of Pure, J. W.
Rodger, 42 : Determination in Electrical I'nits of Specific
Heat of Water, Prof A. Schuster, F. R.S., and W. Cannon,
214: Latent Heat of Eva]v>ratiim of Water, E. H. (Iriftiths,
334

Water-Filters, Relative Efficiency of, Surgeon-Major Johnston.

3^
Water-Pipes, Singing, W. B. Croft, 107

Water- Works Engineering, the Principles of, J. H. Tudslierj-

Turner and \. W. Bright more, 146 ; the Water Supply of

Towns, W. K. Burton, 146
Watson (Rev. H. W., F. R.S.), Boltzm.ann's Minimum Theorem,

105 ; the Kinetic Theory of CJases, 222
Watt (Dr. George), a Dictionary of the Economic Products of

India, 4; W. T. Thi.selton-Dyer, F.R.S., 150 ; Dr. \'. Ball.

F.R.S., 150
Walt (James) an<l Ocean Navigation, Dr. Francis IMgar, 475
Watts' Diclionarj- of Chemistry, M. M. Pattison .Muir ami II

Forster .Morley. 27
Waves, .\bnormal .Vllanlic, C. E. .Sironieyer, 437
Weather : Eleven-^'ear Sim-.S|)ot Weather Period and its

-Multiples, H. Helm Clayton, 436
Weather Forecasts, the Pos.sibilities 01 Long-Kange, Prof.

Cleveland .\bbe, 212
Weather-wise Com|«nion, My, 602
Weaving, the Mechanism of, T. W. Fox. 149
Weaving, \arieil f )ccu|)ations in, Louisa Walker, 435
Web Spinning in .Spiders, some Suggestions on the Origin ami

Evolution of. R. I. Pocock, 417
Webb (II. J.), Advanced .\gricullure. 21S
Weber (.Max), Electromagnet Pull. 326
Weights anil Measures, Engli-h. II. J. Chancy, 422
Weinscheiik (Dr.). Origin ol Alpine Ser|>entine.s, Cneiss, and

(Iranite. 326
Weinirand (Dr.), Formation of Uric Acid in .Man, 623
Welby (Frances A.), Neo-\'italism, 43
Weldon (I'rof W. F. R., F.R.S.). \arialion in .\nimals and

Plants, 449
Well-Waier, the X'arial ions in Level of. A. Riccii, S. .'\rcidiacono,

Prof F. H. Ring. 62

XXXVI

Indi

ex

tSuf'pUineMt to Xaturt,
May 30, 1S95

Wellcr (Sluart), Fossil Faiin;is at Sprinyfiekl, Missuuri, 525
Wells (H. (_;.), Science Teachinj; in Schools, 106 : Science

Teaching, 182 ; A|>ixirilions and Tlum^jhl Transference, Frank

I'odmore, 121 ; PhysioU^' for Hes;inners, I'mf. M. Foster,

F. R.S. , and Lewis K. Shore. 195 ; ( )ullines of Hiolojjy, P.

Chalmers Mitchell, 195 ; Practical Methods in Microscopy, C.

H. Clark. 195 : Peculiarities of Psychical Research, 274
Welt (Ida), Active Amybcelic -Acid, 95
Wcthercd (K. R), the Formation of Oolite, 357
Wetterhan ( David), l);is Verh.iltniss der Philosophic zu der

Kmpirischen Wissenschaft von der Natiir, 220 ; Philosophy and

Natural Science, 295
Weyde (Dr. P. H. van der). Death of, 538
Wharton (Captain W. J. L., F.K..S.), Oceanic Temperatures at

Dillerent Depths, 342
Whiston (Will), S4inie Karly Terrestrial Magnetic Discoveries

|>irt.aining to F.ngland. L. .\. Haiicr, 295
Whitliy, Menii>rials of Old, Kev. |. C. -Vtkinson. 149
White KainlHiw, a, Kev. Samuel liarlier, 274
While (Dr. F. 15.), Death and Obituary Notice 01, 345
While (J.), Corrections of .M.aximum and Ex-Meridian Altitudes,

White (Sir William). Hilge-Keels and Stcidiness in First-Class

Kittle-Ships, 568
Whiteley (Mr. .\.), .Melting-Points of Mi.xtures, 454
Whitcley (K. Lloyd), Org.inic Chemistry, the Fatty Compounds,

557
Whitmell (C. T.), Planetary Photography, 5tl
Wiedemann"-, .\nnalen, 70, 190, 334, 357. 406, 619
Wien (Dr. W. ). the Testing of Platinum Pyrometers, 623
Wiggins (Captain) wrcckeil, S3
Wijhe (M. van), the Cranial Nerves of Vertebrates in Aniphi-

oxus, 120
Wildes Theory of the Secular Variation of Terr&strial Magnetism,

L. .\. Bauer, 103
Wiley (II. W.), Ca-ssava as Food, 515
Wilkinson (Mr.), the New Iodine B.-Lses, 346
Wilkinson (W. F. ), Geology of .Vnatolia, 358
Willem (Victor), Origin of Dicrotism and Undulations of Systolic

Plate.iu of .\rlerial Pulsation, 46
Willey (Arthur), Amphioxus and the Ancestry of the Vertebrates,

433
Williamson(Dr. W. C, F.K.S.), Fossil Plantsof Coal Measures,

ii. , the Roots of Calamities, 94
Wilsing (Dr.), the Parallax of Nebula // 2241, 114
Wind (C. H.). Kerr's M.tgnelo-Optic Phenomenon, 48, 62, 168
Wind and Birds' Flight, the. Profs. Langley and Curtis, 156
Wind-Measurement Fx|H;riinents at Eiffel Tower, Koechlin's,

Max de Nansouty, 181
Winds and on Weather .Signs, Theophraslus of Eresus, on,

translated by Jas. G. Wood, 25
Winkler (Prof.), the Atomic Weights of Nickel and Colxill,

281
Wislicenus (W.alter F.), Astronomische Chronologic, 509
Witherby (Harry F.), F'orcsl Birds, their Haunts and Habits.

341
Wolf (I'ro.. M.), Enckc's Comet, 64
Wolfl(Dr. ), the Commercial Extraction of Pure Dextrose .rom

Synipy Mixtures, 395

Wolflfenstein (Dr.), Isolation of .Anhydrous Hydrogen Peroxide.

182
Womack ( Mr. ), a Modification of Ballistic Galvanometer Method

of Determining Electromagnetic Capacity of Condenser. 142
Woman's Share in Printitive Culture, t ). T. Mason. 244
Wood in .Shipbuilding, Wanted a Substitute for, 490
Woi>d (las. t'l.), Theophrastus of Ere.sus, on Winds and on

Weather Signs, translated by, 25
Wood (W. II.). the .Vurora of November 23, 1894, 390
Woodhead (1). Ci. Sims), the Antitoxic Serum Treatment o

Diphtheria, 402, 425
Wowls (J. D. ), the Province of .South .\uslralia, 221
Workman (Thos. and M. E. ), .Malaysian Spiders, R. I. Pocock,

99
Worthington (Pro.. .\. .M., F.K.S.), Gravitation, 79
Wright (G. 1'.), Glacial Phenomenaof Newfoundland, Laboradipr.

and South Greenland, 430
Wrightson (T. ), Identity of Phenomena of Welding in Iron willi

Kegelatitin in Ice, 453
Wiillner (.\.), Lehrbuch der F,\perimenlalphysik, 3S7
W'untlt (Wilhelm), Lectures on Human and .\ninial Psychologv.

•73
Wyatt (Claude W.), British Birds, 31S
Wynne (Dr. W. Palmer), the Teaching University for London.

297

\'ellow Fever, the Transmission 01, Dr. .\bery, 300

Vendell (Mr.), a New Short Period Variable, 233

Vule (G. U.), Pass;ige of Oscillator Wave-Train through Plate of

Conducting Dielectric, 310; a Simple Form of Harmonic

Analy.ser, 501

Zenith Telescope, a New Form of, Louis Fabry, 564
Zimansky (E.), Elastic Behaviour of Zinc at Different Tempera-

tures, 357
Zirkel (Dr. Ferdinand), Lehrbuch der Petrographie, 290
Ziwet (.\lo\ander), an Elementary Treatise on Theoretical

Mechanics, loi, 533
Zodiacal Light, the, Rear-.Vdmiral J. P. Maclear, 391
I Zoology: .\<l(hlions to the Zoological Gardens, 21, 59,64,85, 114.
132, 160, 183, 207, 233, 253,301,327,347,373,395,424.
443,471,493, 516, 542, 564, 589, 616; Zoological .Society.
94, 119, 191, 311, 407, 479, 502, 550, 575 : Dealh of Di.
Kret.sclimar, iS; the Horse, Prof. N. S. Shaler, 44: the
Visceral .\iiatoniy of Ornithorhynchus, F. E. Beddard, I'.R.S..
191 ; the Zoological Record, .S. Pace, 223 : the Surinam
Waler-Toiid. 230 : a Handbook to the Primates, H. O. Forbes,
242 ; Platypus Embryo from Intrauterine Egg, J- I'. Hill and
C. J. Martin, 264 ; Life at the Zoo, C. J. Cornish, 27() ;
Foraminifera from the .\rabian .Sea, F. Chapman, 511;
Breeding Habits of Brazilian Tree- Frogs, Dr. E. \. tiu-ldi,
407; the I'auna of the Lower Cambrian, Prof. W. K. Brooks,
423 ; the .\rclic Hare in Ireland, 614
Zuntz (Pri'f. ), Measurement of Blood in Circulation and Worl
done by Heart, 216: ElVect of Load on Melabc.iisni and
Body- Functions of Soldiers on the March, 503

NATUKE,. November i. 1894]

NATURE

FIFTY-FIRST VOLUME.

L'ENVOI.

THE completion of a period of twenty-five years, and the publication of fifty
volumes since Nature was established, mark an epoch in its history. The
Editor is anxious to take advantage of it to tender his best thanks to those who have,
from the commencement of the Journal to the present time, not only contributed to
its pages, but have so freely permitted him to appeal to them for advice and assistance.

He feels strongly that it is only owing to their aid and their careful pilotage that
N.ATURE has so far escaped that shipwreck which has been the lot of somewhat similar
ventures, not only in this country, but in Europe and America.

It would have been appropriate, if it had been possible, to have included in
this, the first number of the fifty-first volume, a retrospect of the scientific progress
achieved during the last quarter of a century. It was, however, plainly impracticable
in such a limited space to give a just idea of the various triumphs which have been
accomplished along the many lines of scientific thought and work.

But no elaborate retrospect is needed to prove that since 1869 our scientific
progress has been at a rate which has never been surpassed in the world's history.
Men and ideas have increased ten-fold ; instruments and applications have increased
a hundred-fold. The battle of scientific education has been fought and won, and the
general interest in matters scientific is greatly increasing. Not only are these things
so, but there is everv indication that when L' Envoi to the hundred and first volume
comes to be written — by some other hand — a still more rapid progress will have
to be indicated.

That the same distinguished man of science who wrote the first article in N.vruRK
in 1869 has been good enough to start the fifty-first volume, will doubtless be as
great a source of pleasure to the readers of Nature as it is a source of pride to

The Editor.

Diiriiio- the last hicnty-frve yeai's the folloioing have been among the Contributors

to Nature : —

Abbe, Prof. Cleveland (Washington). Ailken, J., F.R.S. Baker, Sir Benjamin, F.R.S.

Abel, Sir F. A., K C.B., F.R.S. dAlbe, E. E. Fournier. Baker, Sir Samuel W., F.k.S.

Abercromby, lion. Ralph. Allen, Grant. liaker, J. G., F.R.S.

Abney, Captain W. tie W., C.B., F.R.S. .-Vllman, Prof. George James, F.R.S, Balfour, Prof. Francis, F.R.S.

Acland, Right Hon. A. H. D., M.P. Allman, Prof. George Johnston, F.K.S. BaKour, Henry.

Acland, Sir II. W. D., K.C.B., F.R.S. Allardice, Prof. R. E. Bal/our, Prof. I. B., F.R.S.

.\dami, Dr. J. G. Andrewes, Dr. Ball, John, F.R.S.

Adams, Prof. J. C, F.R.S. Aichibald, E. D. Ball, Sir R. S., F.R.S.

Adams, Prof. W. G., F.R.S. Argyll, Duke of. K.G., F.R.S. Ball, Dr. y., F.R.S.

Adamson, Prof. R. Armstrong, Lord, I'.R.S. Bambcr, E. 1".

Agassiz, Prof. Alexander (Camb., Mass.). Armstrong, Prof. H. E., F.R.S. Barlow, W. H., F.R.S.

Airy, Sir G B , F R.S. Ayrton, Prof. NY. E., F.R.S. Barrett, Prof. W. F., F.R.S. •

List of Contributors

[NA TURE, Xmemher t, 169+

Bams, Dr. Carl.

Bashforth, Kev. F.

Basset, A. B., F.R.S.

Bastian, Dr. H. C F.R.S.

Bate, C. Spence, F. R.S.

Bates, H. W., F.R S.

Bather, J. A.

Bauerman, Hilary.

Beale, Dr. Lionel S., F.R.S.

Beard, Dr. I.

Beddard, F.' E., F.R.S.

Beddce, Dr. J., F.R.S.

Bedford, Dr. J.

Bedson, Prof. Philips.

Beer, Dr. Bsrthold.

Bell, Sir I. Lowthian, F.R.S.

Bennett, A. W.

Bentham, George, F.R.S.

Berkeley. Rev. .\I. J., F.R.S.

Bettany, G. T.

Bevan, E. J.

Bickerton, Dr. T. H.

Bidwell, Shelford, F.R.S.

Black, William.

Blake, Prof. J. F.

Blanford, H. F., F.R.S.

Blanford, Dr. W. T., F.R.S.

Bloxam, G. W.

BIyth, Dr. E.

Bonney, Prof. T. G., F.R.S.

Bordage, Dr. E. (Paris).

Botlomley, Dr. J. T., F.R.S.

Boulenger, G. A.

Bourne, Dr. G. C.

Bowdiich, Dr. H. P.

Bower, Prof. F. O., F.R.S.

Boyce, Prof. R.

Boys, Prof. C. V., F.R.S.

Brailhwaite, Dr. R.

Bramwell, Lord, F.R.S.

Bramwell, Sir F. J., F.R.S.

Brandis, Sir D., K.C.LE., F.R.S.

Brinton, Dr. D. G.

Britten, Jamrs.

Brock, Dr. H.

Brough, B. H.

Brown, H. T., F.R.S.

Brown, Prof. \. Crum, F.R.S.

Browne, Sir J. Crichton, F.R.S.

Bruce, Dr. J. Mitchell.

Brunton, Dr. T. Lauder, F.R.S.

Bryan, G. H.

Bryant, R.

Buchan, Dr. Alexander.

Buchanan, J. V., F.R.S.

Budge, Ur.

Bulman, G. W.

Burnside, Prof., F.R.S.

Busk, George, F.R.S.

Butler, G. W.

Calderwood, W. L.
Capron, j. Rand.
Carpenter, Dr. P. H., F.R.S.
Carpenter, Dr. W. B., F.R.S.
Carruthers \V., F.R.S.
Carus- Wilson, C.
Carus-Wilson, Prof. (Montreal)
Caylcy, Prof. A., F.R.S.
Champion, G. C.
Chaney, H. J.
Chisholm, II. W.
Christie. W H. M., F.R.S.
Chrystal, Prof.

Church, Prof. A. IL, F.R.S.
Claike, C. 15., F.R.S.
Gierke, M.ss A. M.
Clifford, Piof. W. K., F.R.S.
Clowes Pio'. W.
Cockercll, Prof. T. D. A.
Cockle, Sir J., F.R.S.

Collins, F. Howard.

Cole, Prof. G. A. J.

Colomb, Vice-.\drairal.

Conmon, Dr. A. .\., F.R.S.

Cooke, Dr. M. C.

Cope, Prof. E. D. (Phila.)

Copeland, Dr. Ralph.

Core, Prof. T. H.

Corfield, Prof.

Cornish, Vaughan.

Courtenay, W. L.

Creak, Captain. R.N., F.R.S.

Croll, Dr. J., F.R.S.

Crookes, W., F.R.S.

Cross, C. J.

Cunningham, J. T.

Cunningham, Lieut. -Colon el A.

D'Abbadie, \.

Dallinger, Rev. Dr., F.R.S.

Dana, Prof. J. D. (Newhaven, Conn.).

Darwin, Charles, F.R.S.

Darwin, Francis, F.R.S.

Darwin, Prof. G. H., F.R.S.

Davison, Charles.

Dawkins, Prof. W. Boyd, F.R.S.

Dawson Principal Sir J. W., F.R.S.
(Montreal).

Day, Dr. F.

De Cliaumont, Dr.
' De Fonvielle, W. (Paris).

De La Rue, Warren, F. R. S.

Denning, W. F.
i De Ranee, C. E.

Dewar, Prof. J., F.R.S.

Dickins, F. V.

Distant, W. L.

Dittmar, Prof., F.R.S.

Dixon, Prof. H. B., F.R.S.
' Dodgson, Rev. C. L.

Dohrn, Dr. A. (Naples).

Donnelly, General Sir J. K., C.B.

Douglass, Sir J. N., F.R.S.

Dreyer, Dr. J. L. E.

Du B )is-Reymond, Prof. (Berlin).

Duncan, Dr. P. M., F.R.S.

Duneli, J. R.

Dankin, E., F.R.S.
, Dunstan, Prof. W. R.

Duprc, Dr. A., F.R.S.
! Dyer, W. T. Thiselton, C.M.G., F.R.S.

I'.Mifls, Arthur.

E(li;eworth, Prof. F. Y.

Edwards, Prof. A. Mead (Boston, Mass.).

Elgar, Dr. F.

Ellis, Wm., F.R.S.

Elwes, H. J.

Ericsson, Captain J. (New York).

Ernst, Dr. A. (Caracas).

Espin, Rev. T. E.

Etnerid>;e, R., F.R.S.

Evans, Sir John, K.C. B., F.R.S.

Evans, A. J.

Evans, Dr. Sebastian.

Everett, Prof. J. D., F.R.S.

Ewarl, Prof. I. C, F.R.S.

Ewing, Prof. J. A., F.R.S.

resling, Majur-Genei

Either, Proi. W. R.

I'i her, Kev. Osmond,

Kiu„;er.ikl, Prof. G. F.. F.R.S.

Fleming, Prof. J. A., F.R.S.

Klelcher. L., F.R.S.

Flower, Prof. Sir W. H., K.C.B., F.R.S.

Forbes, D.ivid, F.R.S.

Forbes, H. O.

Forbes, Prof. G., F.R.S.

Forsyth, Dr. A. R., F.R.S.

Foster, Dr. C. Le Neve, F. R. S.

Foster, Prof. G. Carey, F. R. S.

Foster, Dr. >L, F.R.S.

Fowke, F. R.

Fowler, A.

Fowler, Principal T.

Frankland, Mrs. P.

Frankland, Prof. E., F.R.S.

Frankland, Prof. P. F., F.R.S.

Fream, Dr. W. H.

Freeman, Prof. E, A.

Friend, Rev. H.

Friswell, R. J.

Fritsch, Prof. Anton (Prague).

Fritsch, Prof. G. (Berlin).

Frost, Dr. P., F.R.S.

Froude, R. E., F.R.S.

Fry, Sir E., F.R.S.

Gadow, Dr. Hans, F.R.S.

Galloway, W.

Galton, Sir Douglas, K.C.B., F.R.S.

Galton, Francis, F.R.S.

Gamgee, Dr. A., F.R.S.

Gardner, H. Dent.

Gardner, I. S.

Garside, \V. H.

Garson, Dr. J. G.

Garstang, W.

Gaskell, Dr. W. H., F.R.S.

Gedies, Prof. P.

Geikie, Sir Archibald, F.R.S.

Geikie, Prof, [.-imes, F.R.S.

Giacosa. Dr. P. (Ro iie).

Giffen. Dr. R., C.B., F.R.S.

Giglioli, Prof. H. H. (Florence).

Gilberi, Sir J. H., F.R..S.

Gill, Dr. David, F.R.S.

Gladstone, Dr. J. II., F.R.S.

Glaisher, Tames, F.R.S.

Glaisher, "Dr. J. W. L., F.R.S.

Glazebrook, R. T., F.R.S.

Goldsmid, Sir F.

Gore, Dr. G., F.R.S.

Gotch, Prof. F., F.R.S.

Gray, Prof. Asa, F.R.S. (Harvard).

Gray, Prof. Andrew

Green, Piof. A. H., F.R.S.

Green, Prof. J. R.

Greenhill, Prof. A. G., F.R.S.

Gregor-Brodic, Dr. T.

Grei;ory, Dr. J. W.

Gregory, R. \.

Grove, Sir W. R., F.R.S.

Gruhb, Sir Howard, F.R.S.

Gumbel, Dr. C. W.

GUnther, Dr. A., F.R.S.

Guppy, Dr. H. B.

Haddon, Prof. A. C.

Haeckel, Dr. E. (Jena).

Ilaldane, J. S.

ILilc, Dr. \V. H. (Brooklyn).

Hall, Maxwell.

Halliburton, Prof. W. D., F.R.S.

Hammond, J.

Hampson, G. F.

Harcouri, Dr. A. G. V., F.R.S

Harcoutt, L. F. V.

Harding, Charles.

Harding, J. S.

Ilarkcr, A.

Ilaikncss, Prof. W. (Washington).

Harley, Dr. George, F.R.S.

Hartley, Prof. W. N., F.R.S.

Hariing, J. E.

Haitog, Prof. M.

HA rURE, Kirvember i, 1894]

List of Contributo7's

111

Harlog, P. I.

Hatch, Dr.

Haughton, Rev. Prof., F.R.S.

Haycraft, Dr. I. H.

Hayward, R. B., F.R.S.

Hazen, Prof. H. A. (Washington).

Head, Dr. H.

Hector, Sir James, K.C.M.G., F.R.S.

(Wellington, X.Z.).
Helinholtz, Prof., F.R.S. (Berlin).
Hemsley, W. B., F.R.S.
Hennessy, Prof. H. G., F.R.S.
Henrici, Prof. O. M. F. E., F.R.S.
Henslow, Rev. G.
Herdman, Prof. W. A., F.R.S.
Herman, R. A.

Herschel, Sir J. F. W., F.R.S.
Herschel, Prof. A. S., F.R.S.
Herschel, Colonel J., F.R.S.
Hicks, Dr. H., F.R.S.
Hicks, Prof. W. M., F.R.S.
Hickson, Dr. S. J.
Hill, Rev. E.
Hincks, Rev. T., F.R.S.
Hind, Dr. J. R., F.R.S.
Hodgkinson, Dr.
Hodgson, J. E.
Hoffert, Dr. H. H.
Hoff, Prof. J. H. van't.
Hofmann. Prof. A. W., F.R.S. (Berlin).
Holden, Dr. E. S. (Cal.).
Holmes, G. C. V.
Holmes, T. V.

Hooker, Sir J. D.. K.C.S.I., F.R.S.
Hopkinson, Dr. J., F.R.S.
Horsley, Prof. V., F.R.S.
Howard, Dr. J. L,
Howes, Prof. G. B.

Howorth, SirH. H„ K.C.I. E., F.R.S.
Hoyle, W. E.
Hudleston, W. H., F.R.S.
Muggins, Dr. W., F.R.S.
Hughes, Prof. T. McK., F.R.S.
Hulke, I. W., F.R.S.
Hull, Prof. E., F.R.S.
Hummel, Prof.

Humphry, Prof. Sir G. M., F.R.S.
Hunt, Dr. H. Sterry (Canada).
Huntingdon, Prof. T.
Hurst, Dr C. H.
Huxley, Right Hon. T. H., F.R.S.

Ingleby, Dr.
Irving, Rev Dr.
Ito, t. (Tokio).

Jack, Prof. W.

Jackson, J. R.

Janssen, M. (Paris).

Japp,Prof. F. R., F.R.S.

Jaslrow, Dr. J. (Madison).

Jeffrys, J. Gwyn, F.R.S.

Jevons, Prof. W. Stanley, F.R.S.

Johnstcin, Dr. Keith.

Joly, Dr. J., F.R.S.

Jones, Chapman.

Jones, Prof D. K.

Jones, Pro(. T. Rupert, F.R.S.

Joule, Prof. J. P., F.R.S.

Judd, Pr..f. J. W., F.R.S.

Jukes-Browne, A. J.

Kanthack, Dr. A. .\.

Kay, J. Taylor.

Keane, Prof. A. H.

Keltie, |. Scott.

Kelvin, Lord, P.R.S.

Kennedy, Prof. A. B. W., F.R.S.

Kent, W. Saville.

Kenwood, Dr.

Kinch, Prof. E.
Kingsley, Rev. Charles.
King, Dr. George, F.R.S.
Kirby, W. F.
Klein, Dr. E., F.R.S.
Klein, Prof. F. (GottiDgen).
Knott, Dr. C. G.
Kropotkin, Prince.

Lamb, Prof. H. F.R.S.

Lan;5, Andrew.

Langley, E. M.

Langley, J. N., F.R.S.

Langley, Prof. S. P. (Washington).

Lankester, Dr. Edwin, F.R.S.

Lanke.ster, Prof. E. Ray, F.R.S.

Lapparcnt, Prof. A. de (Paris).

Lapworlh, Prof. C, F.R.S.

Larden, W.

Larmor, Dr. J., F.R.S.

Lavis, Dr. H. J. Johnston.

Lawes, Sir J. B., F.R.S.

Lawrence, Sir J. J. Trevor.

La Touche, T. D.

Lea, Dr. W. Sheridan, F.R.S.

Le Conte, Prof. J.

Leech, Proi. D. \.

Lefroy, General Sir J. II., F.R.S.

Leiand, C. G.

Lendenfeld, Dr. R. von (Czernwich).

Levi, Prof. Leone.

Lewes, Prof. V. B.

Ley, Rev. W. C.

Liveing, Prof. G. D., F.R.S.

Liversidge, Prof. A., F.R.S. (Sydney).

Lloyd-B izward, J. J»

Lockyer, J. Norman, C.B., F.R.S.

Lockyer, N. J.

Lockyer, W. J. S.

Lodge. Prof. -A.

Lodge, Prof. O. L, F.R.S.

Loftie, Rev. W. J.

Love, A. E. H., F.R.S.

Lowe, E. J., F.R.S.

Lubbock, Kight Hon. Sir John, F.R.S.

Luiggi, L. (Genoa).

Lupton, Sydney.

Lydekker, R., F.R.S.

Lyons, Capt. II. G.

Lynne, W. T.

MacalLster, Prof. Alex., F.R.S.

Macjlister, Dr. Donald.

M.acDowall, .\. B.

Macf.idyen, Dr. A.

Mackinder, H. J.

MacLeod, Prof. H., F.R.S.

MacMahon, Major, F.R.S.

Madan, H. (J.

Magnus, Sir Philip.

Major, Dr. C. J. Forsyth

Mallet, Dr. J. W., F.R.S.

Mallock, A.

Marcet, Dr. W., F.R.S.

Maikham, Clements, C.B., F.R.S.

Marriott, W.

Marr, J. E., F.R.S.

Marshall, IT. John. F.R S.

Mar-hall. Prof. Milnes, F.R.S.

Martin, Prof. H. N., F.R.S. (Baltimore).

Martin, Dr. S.

Maskelyne, Prof. N. Story, F.R.S.

Massee, G.

Masson, Prof. Orme (Melbourne).

Maste.s, Dr. M. T., F.R.S.

Mather, T.

Maudslay, A. P.

Maunder, E. W.

Maxwell, Prof J. Clerk, F.R.S.

Mcintosh, Prof. W. M., F.R.S.

McKendrick, Prof. J. G., F.R.S.

McKonnel, J. C. V#

McLachlan, Robert, F.R.S.

McNab, Prof. W. R.

Meldola, Prof. R., F.R.S.

Meldrum, Dr. Charles, F.R.S. (Mauritius).

Mendeleeff, Piof. (Moscow).

Mercier, Dr. C.

Merriam, Dr. C. Hart (Washington).

Merrifield, Mrs.

Meyer, Dr. A. B.

Miall, Prof. L. C, F.R.S.

Michelson, Prof. A. .\. (Chicago).

Miers, H. A.

Mill, Dr. H. R.

Miller, Dr. A. K.

Mills, Prof E. J., F.R.S.

Milne, Prof. John, F.R.S.

Minakata, K.

Minchin, Prof.

Mitchell, P. C.

Mivart, St. George, F.R.S.

Monck, W. H. S.

Moncrieff, W. D. Scott.

Moore, J. E. S.

Morgan, Prof. C. Lloyd.

Morris, Dr. D., C.M.G.

Moseley, Prof. II. N., F.R.S.

Mueller, Baron F. von, K.C.M.G., F.R.S.

(Melbourne).
Muir, M. M. Pattison.
Muir, Dr. T.

Muller, Dr. Hugo, F.R.S.
Muller, Prof. Max.
Muichison, Sir R., F.R.S.
Murphy, J. J.
Murray, Dr. G. H.
Marrav, Dr. John.
Murrell, Dr.
Myers, Dr. .\. T.

Nathorst, Prof. A. G. (Stockholm).

Newall, R. S., F.R.S.

Newcomb, Prof. S. (Washington).

Newton, E. T.. F.R.S.

Newton, Prof. H. K. (Newhaven, Cona.).
I Newton, Prof. A., F.R.S.
I Nicholson, G.

Niven, W. D., F.R.S.

Nordenskiold, Baron.

Nordenskiold, G.

Notter, Prof.

Odling, Prof. W., F.R.S.

Ogilvie, Miss M. M.

Oliver, Prof. D., F.R.S.

Oliver, Prof F. W.

Ormerod, Miss.

O'Reilly, Prof

Osborn, Prof. H. F. (New York).

Osten-Sacken, Baron (Heidelberg!

Otie, Miss.

Owen, Sir Richard, F.R.S.

Parker, Prof. T. J., F.R.S.
Parker, Prof. W. K., F.R.S.
Parker, Ptof W. N.
Parkes, Dr. Louis.
Parry, John.
Parson.'^, Dr. II. F.
Payne, Dr. J. F.
Pearson, Prof Karl.
Peddie, Dr. W.
Pengelly, W., F.R.S.
p. nrose, F. C, F.R.S.
Perkin, Dr. W. H., F.R.S.
Perry, Prof John, F R.S.
i Perry, Father. F.R.S.
1 Peirie, Prof W. M. Flinders.
Pickard-Cambridge, Rev. O., F.R.S.

IV

Li^t of Contributors

\XA TirRE, h'r.'einier i, 1894

Pickering, Prof. E C. (Cambridge, Mass.).

Pickering, Prof. S P. U., F.R.S.

Pigott, t. Diiiby, C.B.

Pitt, Dr. G. N.

Pitt-Rivers, Lieut. -General, F.R.S.

Plarr, Dr. G.

Pbyfair, Lord, K.C.B., F.R.S.

Plummer, \V. E.

Pockels, Miss \. (Go'.tingen).

Pocock. R. I.

Poey, Prof. (Havana!.

Pole, Dr. William, F.R.S.

Potter, Prof. M. C.

Poulton, Prof. E. B., F.R.S.

Power, H.

Poynting. Prof. J. H., F.R.S.

Preece, \V. H., C.B.. F.R.S.

Preston, Dr. S. Tolver.

Prestwich, Prof. J., F.R.S.

Pritchard. Rev. Prof. C, D.D., F.R.S.

Proctor, R. .\.

Purdie, Prof.

Pye-Smith, Dr. H., F.R.S.

Quincke, Prof G. H. (Heidelberg).

Ramsay, Prof. W., F.R.S.

Rankin, .■Vngu?.

Rankine, Prof. W. J. M., F.R.S.

Ranyard, A. C.

Rayleigh, Lord, F.R.S.

Reade, T. Mellard.

Keid, Clement.

Reinold, Prof., F.R.S.

Renard, .Xbhc F. (Brussels).

Reyer, Prof. E. (V'ienna).

Reynolds, Prof. T E., F.R.S.

Richardson, Sir B. W., F.R.S.

Rivers, Dr. W. H. R.

Rix, H.

Roberts-Austen, Prof. W. C, C.B.,

F.R.S.
Robertson, Prof. G. Croom.
Rodger, J. VV.
Kodwell, G. F.
Rolfe, R. A.

Rolleslon, Prof. G., F.R.S.
Romanes, Dr. G. J., F.R.S.
Roscoe, Sir H. E., F.R.S.
Rosse, Lord, F.K.S.
Koulh, Dr. E. J., F.R.S.
Royston-Pigotr, G. W., F.R.S.
Rucker, Prof. A. W., F.R.S.
Rudler, F. W.
Rufier, Dr. M. A.
Runge, Prof. C. (Hanover).
Kuskin, John.

ku-scll, H. C ,C.M.G , F.R.S. (Sydney).
Russell, \V. II. L., F.R.S.
Ruisell, Dr. W J , F.R.S.
Russell, lion. Rollo.
Rutherford, Prof. VV., F.R.S.

Salvin, Osbert, F.R..S.

Sanderson, Prof J Burdon, F.R.S.

Saraain, Dr. K. (fleneva).

Saycc, Prof. A. H.

Schafer, Prof. E. A., F.R.S.

Schlich, Prof.

Schorlcmmer, Prif. C, F.R.S.

Schunck, E., F.K.S.

Schuster, Prof. A., F.R.S.

Schweinfurth, Dr.

Sclater, Dr. P. L., F.R.S.

Scott, Dr. D. H., F.R.S.

Scott, R. H., F.K.S.

Scudder, S. H.

Searle, G. F. C.

Sedgwick, Prof, F.R.a

Seebohm, Henry.

Seeley, Prof. H. G., F.R.S.

Semon, Dr. K.

Sharp, Dr. D.

Sharpe, Dr. R. Bowdler.

Shaw, Dr. John.

Shenstone, \V. A.

Sherrington, Dr. C. S., F.R.S.

Shipley, .-V. E.

Shore, Dr. E. A.

Sidgreaves, Rev. \V.

SiJgwick, .\lfred.

Silvester, F. W.

Skeat, Kev. Prof.

Sklarek, Dr. W. (Berlin).

.Smallwood, Dr. (.Montreal).

Smith, Rev. F. J., F.R.S.

.Smith, Worthington G.

Smith, Prof. \V. H. G.

Smith, I'rof. W. Robertson.

Smith, Prof. C. Michie.

Smith, Dr. Lorrain.

Smith, H. LI.

Smithells, Prof A.

Smyth, Prof C. Piazzi.

SolLis, Prof, F.R.S.

Sorby, Dr. H. C, F.R.S.

Spencer, Herbert.

Spencer, Prof W. B. (Melbourne).

.Spottiswoode, \V., F.R.S.

Starling, Dr. E. H.

•Stebbing, Rev. T. R. R.

Stevenson, C. A.

Stewart, Dr. R. \V.

Stewart, Prof Halfour, F.R.S.

Stirling, Dr. E. C, C.M.G., F.K.S.

(Adelaide).
-Stokes, Sir G. G., F.R.S.
Stoney, Dr. Johnstone, F.R.S.
.Strachey, Lieut. -General R., F R.S.
Strieker, Prof S.
Stroud, Prof.
Sully, Prof. James.
Sylvester, Prof. J. J., F.R.S.
Symons, G. J., F.K.S.

Tail, Prof. P. G.

Taylor, Albert.

Taylor, Sedley.

Tcall, J. J. II., F.R.S.

Tegetmeier, W. H.

Ten Kate, Dr. II.

Tennaiit, Lieut. -General, F.R.S.

Thompson, Dr. C. Symes.

Thompson, I'rof. D'Arcy \V.

Thompson, Prof. S. P., F.K.S.

Thomson, Sir Wyville, F.R.S.

Thomson, Prof James, F.R.S.

Thomson, Prof J. J., F.K.S.

Thorpe, Prof T. E., F.K.S.

Tildeii, Prof \V. A., F.R.S.

Tilchcner, Dr. E. B.

Tizard, Captain, F.R.S.

Tomes, Charles C.
Tomlinson, C, F.R.S.
Tomlinson, H., F.R..S.
I Topley, \V., F.R.S.
Trail, Prof I. W. H., F.R.S.
Tr.nquair, Prof R. H., F.R.S.
Trimen, Henry, F.R.S. (Ce)lon).
Trouton, F. T.
Tucker, R.
Tuckwcll, Rev. W.
Tuke, Dr. Hack.

Turner, Prof. Sir \Villl.-»m, F.R.S.
Turner, Prof II. II.
Tutton. .\. E.
Tylor, Dr. E. B., F.R.S.
Tyndall, Prof John, F.K.S.

Unwin, Prof W. C, F.R.S.

Varigny, Dr. H. de.
Vaughan, W.
Veley, V. H., F.R.S.
Venn, Dr. J., F.R.S.
Vignoles, C. B., F.R.S.
Vines, Prof S. H., F.R.S.

Walker, Prof J.

Wallace, Dr. A. R , F.R.S.

Wallace, Prof. R.

Waller, Dr. A. D., F.R.S.

W'alsingham, Lord, F.R.S.

Ward, Prof. H. Marshall, F.R.S.

Warington, R., F.R.S.

Watson, W.

Watts, W. W.

Weisniann, Prof. \. (Freiburg).

Weiss, Prof

Weldon, Prof W. F. R., F.R.S

W^ells, H. G.

Wethered, Dr. F. G.

Wharton, Captain W.J. L., P.N., F.R.S.

Wheatstonc, Sir Charles, F.R.S.

Whipple, G. M.

Whitaker, W., F.R.S.

White, W. H., C.li. , F.R.S.

Whitehead, C.

Wilde, IL, F.R.S.

Williams, W. M.

W'llliamson, Prof A. W., F.R.S.

Williamson, Prof W. C, F.R.S.

Willis, Dr. A. R.

Wilson- Barker, Captain David.

Woodhead, Dr. .Sims.

Woodward, H. B.

Woodward, H. H.

Woodward, .V. Smith.

Woodward, Dr. II., F.K.S.

Wooldridge, Dr. L. C.

Worthingion, Prof A. M., F.R.S.

Wright, Dr. C. R. Alder, F.R.S.

Wright, Dr. E. P.

Wrighlson, Prof J.

Wynne, Dr. VV. P.

Vearsley, P. M.
Veo, Dr. J. B.
Young, .Sir George.
Young, Dr. Sydney, F.R.S.
Young, Prof C. A. (I'rincetown, New
Jersey, U.S.A.).

A WEEKLY ILLUSTRATED JOURNAL OF SCIENCE.

** To the solid ground
Of Nature trusts the mind which builds Jor aye." — WORDSWORTH.

THURSDAY, NOVEMBER i, 1S94.

PAST AND PRESENT.

JUST five-and-twenty years ago, the Editor of
Nature did me the honour to request that I
would write the leading article for his first number.
In complying with my friend's wish, I said that I
could think of no more appropriate preface to a
journal, the aim of which was " to mirror that
fashioning by nature of a picture of herself in the
mind of man," which is called science, than an
English version of the wonderful rhapsody Die
Natiir, which is to be found among Goethe's works,i
and which had been a source of instruction and
delight to me from my youth up.

Whether my estimate of the fitness of these preg-
nant ajjhorisms for the place assigned to them was
shared by more than half-a-dozen of the readers to
whom they were submitted, is very doubtful ; indeed,
I feel bound to confess that a rumour reached my
ears, to the effect that some authorities, apparently
of the school of the most noble Festus, in their
haste, failing to discriminate between the great poet
and his translator, opined that much attempt to
learn, if not much learning, had made me mad.

A verdict based on a mistake so flattering to any
literary vanity I might possess could be borne with
equanimity. Indeed, in view of the general state of
opinion among those interested in physical science at
the time, I had no right to imagine that a presenta-
tion of a theory of the universe based exclusively upon i
the scientific study of nature — a prose poem, which |
stands in somewhat the same relation to the

^_ A better traiisKition th.in mine and .an intercstinp account of the very i
curion^i obscurity which hangs ahoul the parentage of Pic ,\rt/wrarc to i)e
found in Mr. J. Bailey S.iunders* recently published " Goethe's Aphorisms I
and Reflections."

NO. 1305, VOL. 51]

philosophy of Spinoza as the " Essay on Man "
to that of Shaftesbury and Bolingbroke — would be
intelligible to more than a small minority; or ac-
ceptable to more than a fraction of even that fit
though few company.

At that time, it was rare for even the most
deservedly eminent of the workers in science to
look much beyond the limits of the specialty
to which they were devoted ; rarer still to meet
with any one who had calmly and clearly thought
out the consequences of the application, in all
the regions into which the intellect can penetrate, of
that scientific organon, the power and fruitfulness of
which, within their particular departments, were so
obvious. 1 hough few read, and fewer still tried to com-
p rehend the writings oi Francis Bacon, a respectable,
almost venerable, tradition bid us glorify him as the
guide, philosopher, and friend of science ; and more
es pecially held him up as our exemplar in his insistence
upon the division of the world of thought into two —
an old and a new — but, unlike the corresponding
divisions of the terrestrial surface, separated by im-
passable barriers. In the new, the strict adherence
to scientific method was inculcated, and a rich reward
of benefits to man's estate promised to the faithful ;
in the old, on the contrary, scientific method was to
be anathematised, while absolute dependence was to
be placed on quite other mental processes. Men
were called upon to be citizens of two states, in which
mutually unintelligible languages were spoken and
mutually incompatible laws were enforced ; and the/
were to be equally loyal to both.

People engaged in the ordinary business of life
were not much troubled by difliiculties which were
not forced upon them by their avocations. Nor,
among the men of science, did they press hardly on
the mathematicians, the physicists, and the chemists.

NA TURE

[November i, i !S94

At one time, the astronomers underwent sundry per-
turbations, yet these somehow got smoothed over and
ignored. But there was serious trouble among the
geologists and biologists. However sincerely they
might tn,- to shut their eyes, it was impossible to be
wholly blind to the flict that for them the two worlds
were not separable. On the contrary, it was be-
coming plainer and plainer that a vast tract, hitherto
claimed for the old, was being steadily invaded and
annexed by the citizens of the new world.

Fifty years ago the tension was already serious, but
matters had not got so far as to seem desperate. It
was possible for very eminent and, at the same time,
perfectly sincere men, to keep their scientific and
their other convictions in two separate logic-tight
compartments. Indeed, it was said that some, per-
haps too deeply bent on the search after final causes,
found a reason for the duplicity of the cerebral
hemispheres, in their adaptation to the purposes of
this duple.K intellection. Conducive to outward and
inward peace as might be the convention, in virtue of
which science was to be kept grinding at the mill of
utility, and (by way of completing the resemblance to
Samson) carefully blinded, or at any rate hoodwinked
lest glimpses of a nobler field of action should end in
an outbreak on th.- Philistines, the dilhculty of ob-
serving it, as uniformitarian principles obtained the
ascendant among the geologists, became insuperable.
Outside the narrow circle of the peace at-any-price
"reconcilers," the/a:c Baconiana was plainly coming
to an end in the middle of the century. It was
finally abolished by the publication of the " Origin
of Species."

The essence of this great work may be stated
summarily thus : it aflSrms the mutability of species
and the descent of living forms, separated by differ-
ences of more than varietal value, from one stock.
That is to say, it propounds the doctrine of evolution
as far as biology is concerned. So far, there is nothing
new in Darwin's enterprise. So far, we have merely
a restatement of a doctrine which, in its most
general form, is as old as scientific speculation. So
far, we have the two theses which were declared to
be scientifically absurd and theologically damnable
by the Bishop of Oxford at the meeting of the British
Association at Oxford in i860.

It is also of these two fundamental doctrines that,
at the meeting of the British Association in 1894, the
Chancellor of the University of Oxford spoke as
follows : —

" Another lasting and unquestioned effect has re-
sulted from Darwin's work. He has, as a matter of
fact, disposed of the doctrine of ihe immutability of
species.'

And

" Few now are found to doubt that animals separated
by differences far exceeding those that distinguish what
we know as species have yet descended from common
ancestors."

Undoubtedly, every one conversant with the state
of biological science is aware that general opinion
has long had good reason for making the volte face
thus indicated. It is also mere justice to Darwin
to say that this "lasting and unquestioned" revolu-
tion is, in a very real sense, his work. And yet it is
also true that, if all the conceptions promulgated in
the " Origin of Species '' which are peculiarly Dar-
winian were swept away, the theory of the evolutici
of animals and pl.mts would not be in the slightcbi
degree shaken.

Ever since I began to think over these matters it
has been clear to me that the question whether the
forms of life on the globe have come about by evolu-
tion, or in some other way, is an historical problem,
and must be treated as such. Either there arc
records of the process, or there are not. If there
are not, we are shut up to the devising of more or
less probable hypotheses based on indirect evidence.
If there are adequate records, our business is tu
decipher them, and abide by what they tell us. Now.
in 1859, there was no doubt about the existence ui
records ; nor any about the fact that they extended
over a vast period of time ; nor any about the order
of succession of the facts they registered. But, there
was also no doubt in the mind of any one who looked
critically into these records, that, in spite of their
seeming copiousness, they were the merest fragments,
torn and tattered remnants of the continuous
series of documents which once existed. But, very
largely in consequence of the stimulus given by
Darwin,' palxontological research was taken up with
new vigour, and with marvellous success. So that,
in 1878, I felt justified in writing—

" On the evidence of paUvontoIogy, the evolution of
many existing forms of animal life from their predecessors
is no longer an hypothesis but an historical fact."-

And in 1880 —

" If the doctrine of evolution had not existed, paheon-
tologists must have invented it, so irresistibly is it forced
upon the mind by the study of the remains of the Tertiary
Mammalia which have been brought to light smce

I am not aware that these statements have ever
been controverted; and, in view of the following
deliverances of the author of the most authoritative
recent treatise on Palaeontology, I think they are not
likely to be :

1 IlrilUh AssociAtion for thf Advancement of Science, Oxford, .894.
Address of the Most Hon. the Marqun of balisbury, Presldtnl.
■i -Collccled Esiays," vol. ii. p. "6. ■• ^*"'- P- '<■•

NO.

VOL.

!•]

November i, 1894]

NA TURE

\ "Recent investigations have utterly shattered the

ilbelief in cataclysms. The conviction has arisen that the

I process of the development and metamorphosis of

[organic beings was gradual and uninterrupted, and that

sharp lines of demarcation are to be found only where

considerable changes in the conditions of existence, and

especially in the distribution of land and water, have

brought about great modifications in the world of life or

interruptions in the formation of sediment." (Zittel :

" Handbuch der Pateontologie." Bd. I. p. 23.)

And, again, in the recently completed final volume
•of this standard work we read :

"The whole history of the evolution of the mammalia
from the Trias to the present day, in spite of all de-
ficiencies in the record, plainly shows that the genetic
] -connection of the several Faunas, whatever geological dis-
turbances may have taken place, was never completely
interrupted ; and that each of these associations of
animals has arisen by gradual transformation of the
constituents of its predecessor, and has furnished the
stock of its successor." (Bd. IV^ p. 764.)

However often, therefore, thoughtlessness, or
polemical dexterity, may confuse issues which are
totally distinct, biological evolution rests, in per-
fect security, on the firm foundation afforded by the
•study of the remains of the animals and plants, which
have successively peopled the world during the
untold ages of its past history. The coming into
being of the present forms of life has happened so,
and in no other way.

And, as I pointed out, si.\teen years ago,

" It is only the nature of the physiological factors to
which that evolution is due which is still open to
■discussion.'' '

For me, the claim of the doctrine of evolution
i.0 be taken into account in all philosophical and
other views of the nature of things turns upon whether
it possesses a solid foundation in fact or is a
mere speculation. No doubt, whenever astronomers
universally accept what is called the Kant-Laplace
theory of the heavens, a notable addition will be
made to this indispensable objective foundation of
the doctrine. Whenever chemists accept the evolu-
tion of the so-called elements from a materia prima,
there will be a further grand addition. But, for the
present, I venture to suppose that the palaiontological
base is surest. And, at any rate, so far as the claims
■of science to be heard in regard to the problems of
human life are concerned, it is, far and away, the
most important. If man has come into existence by
the same process of evolution as other animals ; if
his history, hitherto, is that of a gradual progress to
a higher thought and a larger power over things ; if
that history is essentially natural ; the frontiers
of the new world, within which scientific method is
supreme, will receive such a remarkable extension as
to leave little but cloudland for its rival.

1 " Collected Essays," vol. ii. p. aa6.
NO. 1293, VOL. 51]

Experience teaches me it is by no means im-
possible that if I were to stop here, what I have said
would be rejjresented, and even believed, to be a
repudiation of " Darwinism." Yet no conclusion
could be more utterly devoid of foundation.

" The combined investigations of another twenty years
may, perhaps, enable naturalists to say whether the
modifying causes and the selective power, which Mr.
Darwin has satisfactorily shown to exist in nature, are
competent to produce all the effects he ascribed to them ;
or whether, on the other hand, he has been led to over-
estimate the value of the principle of natural selection, as
greatly as Lamarck over-estimated his ''era causa of
modification by exercise."

...."' My sons dig in the vineyard,' were the last
words of the old man in the fable ; and though the sons
found no treasure they made their fortune by the grapes."'

These two paragraphs occur at the end of the
critical notice of the " Origin of Species," which I
wrote in 1859. The citations I have already given
from Zittel sufficiently show what has come of
"digging in the vineyard"; there is another (Bd. I.
p. 42) much to the present purpose.

" For the naturalist, evolution (</;> Descendeiiz theorie)
offers the only natural solution of the problem of the
development and succession of organic beings. But as
to the causes which bring about the modification of
species, and especially the change in a given direction,
opinions are yet greatly divided. That the principle of
natural selection, discovered by Darwin, leaves many
phenomena unexplained is no longer denied by even the
warmest followers of Darwin."

It will be observed that at any rate one of these
"warmest followers" has never thought of denying it
On the contrar)-, he has over and over again brought
the difficulties prominently forward. Nevertheless,
I doubt as little, now as heretofore, that the proba-
bilities are greatly in favour of our finding a way to the
causes of evolution by pertinacious study of variation
and natural selection. There are large fields for
inquiry open on all sides. How much has yet been
done, for example, towards ascertaining the eflfect of
external conditions on the struggle for existence within
the organism and the production of varieties as a
consequence of that struggle ; or towards an adequate
experimental study of variation? The supposition
that problems such as these, and others that might
easily be mentioned, could be finally solved, even in
thirty-five years, is one that would not enter the mind
of a competent biologist : and the parade of the
mutual contradictions and the intrinsic weaknesses of
the hypotheses which, hitherto, have been more or
less tentatively propounded, as if they had anything
to do with the truth or falsehood of the doctrine
of evolution, should not be taken too seriously.

T. H. Huxley.

NATURE

[November i, 1894

ECONOMIC PRODUCTS OF INDIA.

A Dictionary of the Economic Products of India. By
George Watt, M.B., CM., C.I.E., assisted by numerous
contributors. In six volumes (vol. vi. in four parts),
18S9-1S93. Published under the authority of the
Government of India, Department of Revenue and
Agriculture. (Calcutta : Superintendent of Government
Printing.)

THE completion of this important work adds enor-
mously to the facilities previously existing for
acquiring a knowledge of the vegetable, mineral, and
animal products of our Indian empire. The object of
the dictionary is to give a complete account of all
Indian products that have been in any way utilised by
man, however smiU or trivial the use of them may have
been. As a large mijority of the products are of
vegetable origin, the appointment of a botanist as editor
and principal author was essential, and the Government
of India may be fairly congratulated on the result.

In the preface to the first volume the author states
that he has had " to keep in view a two-fold purpose ;
viz. on the one hand to supply scientific information
which may be useful to the administrative oflfi:er, and on
the other to meet the requirements of the reader ia
search of definite information regarding Indian
economics." Whether another purpose was to produce
a large book is not stated, bat no feature of the work is
more conspicuous than that it consists of nine bulky and
rather closely-printed volumes.

In general plan the dictionary consists of long and
elaborate accounts of the more important articles of
commerce produced in India, such as various grains,
dyes, oils, tea, cotton, sugar, indigo, wool, silk, &c., and
shorter notices of less valuable products. As a general
rule each vegetable product is described under the
scientific name of the plant from which it is obtained,
cross references being supplied where necessary under
English and Indian terms, and also under general head-
ings, such as " Oils and Fats," " Timbers," &c. Animal
and mineral products are described under various head-
ings. A general index is promised, and is needed, for
many important English and vernacular terms are not
found in their places. For instance, silk-cotton, semul,
jowari and ju.iri, b:'ijra, cholum, cumboo, charas, ganja,
ng.-ipi, civet (and Viverr.a) may be searched for in vain.
Tasar is inserted, but there is no reference to tusser or
tussah, the common spelling, in the place where these
words would come in alphabetical sequence. The article
on isinglass is slightly out of its proper place, and that
on sharks' fins and fish maws, to which reference is
made under both isinglass and fish, appears to have
been omitted.

Each article, in the case of vegetable products, con-
sists of the scientific name of the plant, with references,
the English name, if one exists, and a list of vernacular
names, followed by full references to the works, scientific
or economic, in which the plant or its products have been
described. Then follow paragraphs on the habitat,
history and useful products, such as dyes, fibres, oils,
gumi, &c., each under a separate heading. Sometimes
a paragraph explains the chemical composition. Under
additional headings arc related the uses to which the
NO. 1305. VOL. 51]

plant or its products are put in medicine, food, or the
arts, and to the paragraph on medicine another is fre-
quently added with "special opinions " by various medical
officers. In the case of trees the structure of the wood
receives special notice. The last paragraph of each
article describes the " domestic and sacred uses." With
mineral and animal products the plan is similar, but
details are given, as a rule, under general headings, such
as horns, skins, wool, iron, &c. In the first volume a
botanical diagnosis of each plant is generally added, bui
not in the later volumes. .A number for each separate
product or use is inserted in the margin to facilitate
reference, the numbers commencing afresh under each
letter of the alphabet.

The longer articles contain full descriptions ol
cultivation, trade, manufactures, and other important
subjects.

Whilst the bulk of the work is by Mr. Watt, many
articles have been contributed, partly or wholly, by other
writers. The list of contributors affixed to the first
volume refers only to that volume, or to that and the
second, for in the prefaces to the third and subsecjuent
volumes several additional names are mentioned, one of
them, Dr. J. Murray, being that of the author of several
important articles. AH of the principal contributors,
except .Mr. Watt (and he holds the degree of M.B.),
belong to the Indian Medical Service, so that it is not
surprising to find a very large space devoted to drugs
and therapeutics. In fact, the whole work might fairly
be termed a dictionary of economic products and
materia medica. Many of the plants catalogued are ap-
parently included solely because of some medicinal or
supposed medicinal use, frequently by ignorant people.
For example, on the last two pages of the work, Zornict
diphylla is introduced on account of its use thus quoted
under the head of" Medicine'' : "The root is given, '.along
with that of Bhadar jhapni, to induce sleep in children.
These plants shutting up their leaves at night have pro-
bably suggested the idea to theojhas." The quotation
is from a report by Mr. Campbell on the " Economic
Products of Chutia Nagpur." No reference can be found
to Bhadar jhapni in its place in the dictionary.

The " special opinions," quoted from various medical
writers on therapeutics, are of a miscellaneous nature,
and no distinction is drawn between notices of the pur-
poses for which drugs are used by competent physicians,
and those of occasions on which they are prescribed by
ignorant hakims or superstitious herbalists. All this
part of the work might have been omitted with advan-
tage ; however useful such opinions might be in a special
work on drugs and therapeutics, the details are out of
place in a description of economic products. One instance
may be quoted. I'nder the head of "Diamond," the
following occurs : " iMcdicinc. — Diamond dust is known
to be a powerful mechanical poison. In Hindu practice
it is, however, to some extent used as a drug" (just as
gold, silver, pearls, and other precious substances are
regarded by unscientific races as possessing great medi-
cinal virtues). The whole extract is too long to quote,
but the " special opinion" runs thus : " Employed as a
poison, it is administered in the shape of dust, as in the
late celebrated case when the Resident of Baroda, Sir
Arthur Phayre, nearly lost his life." The Resident of

1 I

I

November i, 1894J

NATURE

Baroda was Sir Robert Phayre, not Sir Arthur, the well-
known Chief Commissioner of liurma, and the risk to
life was due to an important fact which the distinguished
surgeon, whose name is appended to the quotation, must
have forgotten, the admixture of arsenic with the dia-
mond dust. The latter is simply a mechanical irritant
like quartz sand, or powdered glass, and to term any of
these a powerful mechanical poison is to use a stronger
term than is quite accurate.

The devotion of a large space to therapeutics is not
the only instance in which the bulk of the work is in-
creased by the discussion at length of matters that have
but slight connection with the main subjects of the dic-
tionary, as specified by the author. Perhaps the utili-
sation of several pages under Triticum sativum (wheat)
in the discussion of the depreciation of silver, may be
thought essential, but it is not clear why, under
Papaver soinni/eruin, long extracts should be quoted
from various dispatches to illustrate the attitude of the
Government of India on the Chinese opium question, nor
what bearing on the economic products of India tne seven
pages can have, under I'tlis vini/era, that are taken up
with the history of the vine and of wine. Amongst the
longer articles, 63 pages are given to tea (in addition to
19 on Camtllia thcifera), 77 to tobacco, 87 to indigo, 88
to opium, 12310 sheep, goats, wool and woollen manu-
factures, 152 to rice, 174. to cotton, 238 to silk and silk
manufactures, and 380 to the sugar-cane and sugar.
Almost every one of these articles would require a
separate notice for adequate discussion. For many pur-
poses a condensed account of the history, production,
manufacture, and trade in each case would be more
generally useful as well as more interesting ; but, on the
other hand, it is extremely difficult for the author of a
work like the present to select only those data that are
useful, and no editor can be expected to possess the
special knowledge of every separate subject that will
enable him to do justice to it, and to avoid mistakes.

In the preface to the first volume it is stated that
economic products which belong to the animal and
mineral kingdoms have been but very imperfectly
touched upon. This plan, however, appears to have
been modilied subsequently, since silk and wool, as
already noticed, form the subjects of two of the longest
articles. The accounts of minerals have, for the most
part, been written by officers of the Geological Survey,
or copied from the Survey publications. It is question-
able, however, if any geologist can have written the
following passage under the heading of iron : " Clay
ironstone exists in large deposits in many coal-measures,
and in this situation is known as black band." It is, of
course, only one variety that is known by this name.

No parts of the dictionary, however, stand more in
need of scientific revision than those relating to verte-
brate animals. A few instances will show this. A short
article on " Pheasants, Jungle-fowl, Partridges, &c.,"
commences thus : " The pheasant families of birds,
PhasianidiC, Megapodida, and Gallinie (sic) comprise the
pea-fowl, pheasant, jungle-fowl, and spur-fowl, while
the partridge family, Tetraonidiv, includes the partridge,
snow-cock, and certain forms of quail." A list follows in
which the genera Pavo, Ari^iisianus, and Polyplectron
only are included in the family PhasianidcE, all other
NO. 1305, VOL. 51]

pheasants, amongst them the typical genus Phasianus,
are placed with Megapodiits nicobariensis in the family
Megapodidce, and the so-called family Gallina (which
is really a sub-family of Phasianida) contains Callus and
Galloperdix. These mistakes are apparently copied
from Murray's "Avifauna of British India." In the
article " Oxen," the wild and tame yaks are rightly classed
as one species, but the tame buffalo is separated, under
the name of Btibatus bos, from the wild race, or B. ami.
No reason is assigned for a distinction that is quite
opposed to the views of all modern writers on mam-
malia, nor is any authority given for the name adopted,
which is simply the old Linnasan name Bos biibalus
reversed.

The omission of any notice of ng;ipi [in its proper
place has already been mentioned. This curious
compound of partially decomposed fish with salt is a
most important article of food in Burma, where it may
, be said to replace butter and cheese amongst a people,
who, like the Chinese, hold milk and all substances
I obtained from it in abhorrence. The manufacture of
ngapi is on a very large scale, and the trade in the
I article is e.xtensive, yet apparently the only notice of the
; mode of preparation that occurs in the dictionary
1 (" Fish," vol. iii. p. 367) is apparently erroneous, and cer-
tainly does not apply to one of the ordinary processes.
Three or four different kinds of ngapi are mentioned in
the Burma Gazetteer, and their manufacture described ;
all the processes are radically distinct from that briefly
quoted in the dictionary, whilst no information is given
in the latter as to the trade in the article or its value,
except what may be inferred from the fact that the
revenue from Burmese Fisheries in 18S3 was twelve to
thirteen lakhs of rupees.

In the article on sheep and goats, and in some others,
the authorities for scientific names are quoted on the
botanical, not on the zoological system, and it is rather
strange to find the nilgai caWtd Bosclap/tus tragocamelus,
W. Sclater (instead of Pallas), and the Tibetan gazelle,
Gazella picticaudata, Brooke (instead of Hodgson). The
mutton of the dumba, or fat-tailed sheep, is said to be
very coarse, whereas it is the best mutton in Asia.
The common Indian story, repeated in the dictionary,
under " Camel's milk," that the sweetmeat halwa, brought
from the Persian Gulf, is composed of camel's milk and
honey (vol. ii. p. 64), is a mistake. Errors like the two
last (others might be quoted) are liable to occur in a
work like the present, but the number of mistakes of
various kinds in the articles on animals and animal
products appears to be rather large. It is not easy to
understand why, in an important Government work
like the present, the aid of competent zoologists
could not be obtained to revise the proofs.

A serious mistake may be pointed out in an article on
the yeast plant, described under the somewhat pedantic
heading of Ccrevisicc fermentum. Yeast, it is said, " lives
and increases in the fermenting liquor, but appears to
abstract nothing from it." This mistake may however
have been noticed, for in a later article, on " Malt liquors,"
a correct account of the growth and nutrition of yeast is
([uoted.

One presumably Indian economic product, paper, can
scarcely be said to be favourably represented by the

NATURE

[November i, 1894

material used in the present work, nor are the type and
printing, especially in the later volumes, the best ever
produced in India. Misprints are numerous. One is
amusing : the Tibetan antelope is credited with no less
than ten horns. It is to be hoped that commentators on
the Apocalypse will not be led to believe that a ten-
homed beast really inhabits Tibet.

On the whole, whilst in case a second edition is
required, careful revision is desirable, which might in
some cases take the form of abridgement and the
omission of irrelevant matter, the principal feature of
the work is the large amount of energy that has been
expended in its preparation, and the great effort that
has been made to bring together information from all
quarters. To write a complete account of the products
of India, and to give a full scientific and economic de-
scription, both of the products themselves and of the
sources from which they are derived, are tasks far
beyond the powers of any single individual, and that
could only be thoroughly carried out by a committee of
specialists. W. T. B.

CHINESE AND JAPANESE BUTTERFLIES.
Butterflies from China, Japan, and Corea. By John
Henry Leech, B.A., F.L.S., F.Z.S., F.E.S., &c. 4to.
With forty-three coloured plates. (London : R. H.
Porter, 1S92-1S94.)

UNTIL within the last few years, almost nothing was
known of the Palasarctic fauna, except that of
Europe and the Mediterranean sub-region, and though
butterflies are the most attractive and the easiest collected
of all insects, those with which we were acquainted from
Siberia, the greater part of China, and Japan, might
almost have been counted on the fingers.

Since then, however, great progress has been made.
In the first place, Russian exploration and consolida-
tion have opened up vast regions of previously almost
unknown parts of Asia to science, and the work begun on
the .\mur and in Turkestan by Schrenck and Fedchenko,
has been worthily continued by the Grand Duke Nicholas
Mikhailovitch and his coadjutors, among whom the
brothers Groum-Grshimailo deserve the place of honour.
When shall we see one of our own Royal Princes bring-
ing out a work on the insects of one of our own colonies
to compare with RomanolTs " Mdmoires sur les
L<;pidoptires ? " In Western Europe, such work is left
to private enterprise.

The French Jesuit missionaries, especially the Abbe
David, have penetrated to such out-of-the-way parts of
China, as Mou-pin, and have brought back large collec-
tions of different kinds, including many very remarkable
butterflies, which have been iiluitratcd ^by Oberthiir
in his " ittudes d'Entomologie."

Since the time when Chinaand Japan were thrown open
to Europeans, English entomologists have not been be-
hindhand in the work of collection and description. The
fine collections formed in Japan by Lewis, Pryer, and
Maries have been worked out so well by Dr. Butler and
others, that the Lepidoptera: of Japan are now more
thoroughly known than those of any other part of Asia
except British India. The late Mr. W. B. Pryer published
a work on the butterflies of Japan, in the country itself,
NJ. 1305. VOL. 5 1]

in EngUsh and Japanese, with coloured plates of all the
species known to him ; but as this book is scarce, and
the letterpress very meagre, we are glad that Mr. Leech
has included Japan in the important work which forms
the subject of the present article.

]\lr. Leech commenced his entomological career by the
publication o'f a useful little volume on British Pyralidcr,
and by collecting excursions to the Canary Islands,
Brazil, &c. Subsequently he became interested in the
fauna of Eastern .Asia, and devoted eight years to its
study, and to the accumulation of materials for the present
work, not only by employing experienced collectors like
Pratt and Kricheldorf to explore the interior of China,
but by personally visiting and forming large collections
in the Himalayas, Corea, and Japan ; in Japan, indeed,
he succeeded in capturing almost every species of butterfly
known to inhabit the country. By this means, he gradu-
ally accumulated the fine collections on which he has
based his great work, in which he has been able fully
to describe 650 species, a large proportion of which are
figured in the forty-three excellent coloured plates
which accompany it. We have also a map, and five
plates of scenery (four of Western China and one of
Japan), the second of which exhibits a side-view of the
tremendous and almost perpendicular face of the moun-
tain of Omei-Shan, in the neighbourhood of which Mr.
Pratt obtained many of the most beautiful and interest-
ing butterflies which he discovered.

The usefulness of the work is increased by an interest-
ing introduction, dealing with the literature of the subject,
the countries visited by the author and his collectors,
and a table of geographical distribution, divided into
the following columns : Japan, China, Corea, Amurland,
Himalayas, Thibet, Europe, and "other countries and
regions."

The author remarks in his preface : " It is a matter of
regret that, owing to an almost complete absence of in-
formation respecting habits and life-histories of the
majority of the species, the work is unfortunately less
complete than the author could have wished." .All honour
to him for saying so. It is the duty of every entomo-
logist to seek for and record everything of the kind which
he can obtain ; but entomologists are sometimes too much
disposed to care only for the specimens they receive,
and it would not occur to them to encourage their
collectors, as they easily might do, to record anything
more than dates and localities. Mr.Leech, however, seems
both to have sought for and utilised such information,
so far as it was accessible or obtainable.

On examining Mr. Leech's 650 species of butterflies,
which are distributed among rather more than 150 genera,
it becomes apparent that they are to a large extent
mainly an amplification of the European fauna. About
300 species are found in Europe proper, divided into about
50 genera, of which only about 9 genera, each including
but one, or at most two or three, species of very limited
range, are not represented in Mr. Leech's work. These
are Triphysa, Nciiicobius, Atirolis, Thestor, Zegris,
Doritis, Sftitotltyrus, Thymcticus, and Cyclopides ; and
there is no reason why some, even of these, should
not extend to Western China. In China the European
and Indian faunas meet and mingle ; thus in the
Satyrina, the Mountain Brown butterflies of the genus

November i, 1894]

NATURE

Erebia are far more sparingly represented in China than
in Europe ; but Lethe is far better represented in China
than in India, and Ypihima at least as well. The
tropical subfamilies Morplunce and Acrceince are also
represented in China, the first by four species, one of
which, Stichophtlialma howqtta, is as large and handsome
as a South American Morpho, and the other by one of
the two Indian species, Pareba vesta, which extends its
range to several parts of South-Western China. In
Japan and the extreme east of China, we find one or
two species belonging to peculiarly Nearctic forms, such
as AntJtocIiaris scoiyinus, for example.

In certain large genera, such as Zepkyriis, Thecla, and
Papilio, the number of Chinese species far e.xceeds those
known to occur in Europe ; but in the case of Papilio, at
least, this is mainly due to the large number of properly
Indian species which extend their range to China.

It is among the Papilionida and Pieridcz that we
find some of the most interesting of the Chinese and
Central Asian forms, especially those allied to Pa-nassius,
Aporia, and Colias. There are only about thirteen well-
marked genera of Papilionida, except the hetero-
geneous genus Papilio itself ; and eight of these are
represented in Mr. Leech's district, the other five being
Hypermnesira (South-West Asia), Eurycus (Australia),
Euryades (South America), Thais (South Europe), and
Bhutaiiitis (Bootan). The headquarters of Partiassius,
however, are perhaps in the mountainous districts rather
beyond the range of the present work, as Mr. Leech
enumerates only eight species, which seems to us to be
rather a small number. Many curious genera allied to
Aporia are also found in the south-western districts
of China bordering on Thibet, such as Mesapia,
Davidina, &c., most of which bear a general resem-
blance to our Green-veined White {Pieris napi). Of
these, Oberthiir's genus Davidina is the most curious, as
the wing-cells are divided by longitudinal nervures, a
characteristic which we do not meet with in any other
butterfly. Only four species of Colias are enumerated,
the headquarters of this genus also being apparently
rather beyond Mr. Leech's limits. He has, however,
sunk all the Japanese forms described as distinct by
various authors, as varieties of C. hyale, Fabr. ; but this
is one of those questions which will never be disposed
of to the satisfaction of entomologists without long and
careful breeding of the supposed varieties or species.
Some authors, however, have certainly gone too far in
regarding mere varieties of butterflies as entitled to
specific rank ; while others have erred more seriously in
the opposite direction, by placing together perfectly dis-
tinct species as varieties. It frequently happens that
species which subsequently prove to possess very im-
portant distinctive characters, have a much greater
superficial resemblance to others than obtains between
seasonal or otherwise dimorphic forms of insects which
belong indubitably to the same species. But if a good
species is sunk as a synonym or a variety, the next
entomologist who considers it to be distinct will very
likely overlook the previous notices, and describe it as
new. We are constantly discovering that names which
stand as synonyms in our books really belong to insects
which have since been described as new under other
names.

NO. 1305, VOL. 51]

In taking leave of this extremely interesting book, we
must congratulate Mr. Leech on having successfully
brought to a conclusion a work which will hold a worthy
place among the many valuable local butterfly faunas
which have been published in England, of recent ysars,
by Godman and Salvin, Moore, Trimen, Distant,
and others. ^V • F. K.

OUR BOOK SHELF.

Rainmaking and Sunshine. By John CoUinson.

(London : Swan Sonnenschein and Co., 1S94.)
The only object there can possibly be in giving a
notice of this book is to warn intending purchasers of its
contents, lest they be deceived by the title, and hope to
find some account, more or less interesting, of the experi-
ments that were made in America, a short tmie back, with
the view of procuring a rainfall. This book has not even
that recommendation. One has not much patience with
weather prophets, who base their assertions on conjunc-
tions of the planets, or some equally occult and absurd
methods; but Mr. Collinson is in advance of all such
vendors of nostrums. Not for him the uncertain, or
partial, fulfilment of hazily expressed prophecies, not for
him the long and careful study of signs and portents ;.
he, himself, is the rainmaker, he is the dispenser of sun-
shine and cloud, he is gifted with the divine power that
storms and floods and drought obey. Here is his own
modest statement : " Thus when suitably placed as to
residence, the results of his (the author's,) action on
magnets are certain to produce changes in the weather,
and other effects, as interesting and useful, bearing on
meteorological science generally. They are simply mar-
vellous. Storms, floods, drought, &c.,can be induced, on
the one hand, and the prevalence of sunshine and warmth,
in opposition to coldness and gloom, on the other. His
action in this direction, judging from experience, could
bring any district, and, indeed, the country generally, such
favourable weather as would recall the glories of the
Golden Age." (p. iS.j Another passage that makes one
doubt whether the book is to be taken seriously,
relates how a prophet (Ouery Dr. Falbe, says the author)
foretold bad weather for^ March 2S, 1S93, sudden fall of
the barometer, great conflicts of wind and water, and
various other disasters. " About the same time Prof.
Jenkins foretold that there would be a cyclone with snow
on March 25. I took care that these storms did not
happen.'' (p. 1S6.)

But there is one form of internal evidence which for-
bids us concluding that the author has perpetrated an
elaborate joke. He claims to have given to a whole
nation of holiday-makers ten days of enjoyable weather at
Easter, but refused to exercise his godlike gift on behalf of
suffering humanity at the following Whitsuntide, because
" N O " (in very large capitals) " suitable sign of apprecia-
tion had then been received from any of those who largely
benefited by the results of the fine Easter weather.'
(p. 214.) One would like to know what is the force of
" then " in this sentence. Have the railway companies
rewarded this gentleman since : -And what would be a
suitable sign of appreciation to a man so endowed ? But
enough of this nonsense ; whoever else the book may
amuse or edify, it will scarcely find readers among the
subscribers to Nature. W. E. P.

The Elements of Graphic Statics: a Text-Book for
Students of Engineering. By L. M. Hoskins, Pro-
fessor of Pure and Applied Mechanics in the Leland
Stanford Junior University; formerly Professor of
Mechanics in the University of Wisconsin. (London:
Macmillan and Co., 1S92.)
Although the fundamental ideas of Graphical Methods
in Statics can be traced back to the writings of Stevinus,

8

.VA TURE

[November i, 1894

of Bruges u'. 1600), and although they must have been
employed by scientific engineers, such as Brunei, the
subject of Graphical Statics as known to the mathe-
matician dates only from Maxwell's writings on the sub-
ject, and to Culmann's elaborate treatise in Crerman ;
also to Colonel Sir George Clarke's exhaustive work.

The subject of Statics, which had come to a standstill,
was revivified by the graphical methods now employed
by every engineer and architect.

But as the subject is nothing unless employed prac-
tically by the draughtsman on the drawing board, it has
not yet conquered the prejudices of the abstract mathe-
matician, although many problems of allied descriptive
geometry, required in the construction of inertia ellipses
and curves Tart iii. , are well worthy of the attention
of the pure geometer.

The present treatise is designed as an elementary text-
book for the use of students of engineering ; and the
illustrations are drawn carefully to scale, representing
each some real object.

The method of lettering, attributed to Bow, is now
more appropriately assigned to Henrici ; the author very
rightlv insists upon the fundamental importance of this
lettering, in emphasising the reciprocity existing in the
diagrams.

Incidentally the method of Graphical Statics empha-
sises the proper treatment of Statical problems, which is
always to consider a "System of balancing forces; and
thus to banish the word Resultant from Statics unless
employed to represent the force which if reversed will
balance the remaining forces of the system. G.

A Naturalist on the Prowl. By Eha. Pp. 257.

(London : W. Thacker and Co., i S94.)
From Spring to Fall. By " A Son of the Marshes."

Edited by J. A. Owen. Pp. 239. (London : William

Blackwood and Sons, 1894.)
Thf. author of " A Naturalist on the Prowl " knows how
to write pleasantly on the natural history of the Indian
jungle. There is not a dull page in his book. It is only
rarely that we meet with a volume so full of interesting
observations, and so free from stodginess. In " Eha's "
company we travelled from the first to the last page, here
admiring the keenness of his perception, there laughing
at his humorous comments, and always made happy by
his geniality. He does not "prowl " to kill, neither is he
imbued with the spirit that induces many people to
collect shells and postage-stamps as specimens ; for
though he recognises that " without a collection, a man's
knowledge of natural history becomes nebulous, and his
pursuit of it dilettante," he also knows that there is a pos-
sibility of a man degenerating into a mere collector, and
ceasing to be a naturalist. Mr. R. A. Sterndale enriches
the volume with eighty illustrations, mostly sketched
from life.

The works of " A Son of the Marshes," on country life
and scenery, are renowned for their simple beauty and
sympathetic expression. Under the editorship of Mrs.
Owen, the volume before us, like other books by the same
author, is delightful reading.

Edible and Poisonous Mushrooms. By Ur. M. C. Cooke.
(London: S.P.C.K., 1894)

It may be safely asserted that fewer kinds of fungi are
used for food in Great Britain than in any other country
in Europe. This is the more remarkable when we take
into consideration the indebtedness of the present ad-
vanced state of Mycology to the researches of our
countrymen, amongst whom may be mentioned Bolton,
Sowerby, Badham, Berkeley, and Broome. The author
of the work under consideration has also contributed
very materially to a knowledge of edible kinds of fungi
by various publications, and more especially in promoting
annual fungus forays in various parts of the country.

NO 1305. VOL. 51]

Poisonous fungi liable to be confounded with the
numerous edible kinds are very few in number, and the
majority of casualties, both at home and abroad, are
caused by eating Amanita phalloides, a fungus very
different in appearance from the common mushroom
{Agaricus c-ampi-stris), but which, probably from its neat
and attractive appearance and size, appears to commend
itself to unsuspecting persons, and being usually very
abundant and widely distributed, is likely to be a con-
tinual source of danger until its characters and general
appearance are more generally known.

Dr. Cooke very properly condemns the various rule-of-
thumb methods for discriminating between edible and
poisonous kinds of fungi, and shows that the essential
characters of the various kinds must be thoroughly
grasped, as being the only certain means of identification ;
and this method, with Dr. Cooke's book as a guide, should
not prove a difficult task. The written descriptions of the
various kinds, without being technical, are very clear
and to the point, and the eighteen coloured plates are
excellent. Finally, the best methods of cooking are
given. The book is well printed, attractive externnlly,
and very cheap.

LETTERS TO THE EDITOR.

[The Editor does not hold himselj responsible for opinions ex-
tressed by his correspondents. Neither can he underlaki
to return, or to correspond with the writers of, rejected
manuscripts intended for this or any other part o/'Naturb.
No notice is taken of anonymous communications. ]

What are Acquired Characters?

For some while past, as we all know, a great contest has been
raging as to whether acquired characters of an organism can or
cannot be transmitted from one generation to another ; and
mighty authorities, on the one side, say that they can be ; and
great authorities, on the other, aver that they cannot be.

As a spectator of this contest, I have tried to understand it ;
and, in the first place, I have endeavoured to make out what is
meant by the uhrase " acquired characters'' ; or, in short, what
is meant by the word "acquired," as used, in this connection,
by Weismann, his friends, and his antagonists.

It is evident that the word is not used in its primary and
natural signification • for, .is on the theory of evolution (on which
hypothesis the whole discussion proceeds), man has been
evolved from an anncba or an ascidian, or some other early
form, it follows that every character by which a man differs
from this, his firsl progenitor has been acquired at some time
between the two termini of the course of evolution, and, if the
word were used in its ordinary sense, it would further follow
that none of these characters could be transmitted by man to
his offspring. This is manifestly untrue, for the issue of a
woman is not simply an amuba. In fact, Weismann himself
implies plainly that he does not use the word " acquired " in its
ordinary signification, and asserts that its scientific value lies in
its restricted use. (" Essays on Heredity," English translation,
vol. i., first edition, p. 412.)

It becomes then very important to get at an accurate and
workable definition of the word "acquired" for the purpose in
hand; and such a definition must, I conceive, satisfy the follow-
ing conditions : — (l) It must be such as to include all characters
that are "acquired " wiihin the restricteil meaning of the word,
and to exclude all characters that are not within the meaning ;

(2) it must be staled in physical, and not in metaphysical terms ;

(3) it must not be stated in terms derived from beredit.iliility
or the contrary, or in terms of any hypothesis or theory ; (4)
in order that it may be of use for scientific purposes, it must be
stated in terms that admit of ascertainment and verification.

Of the imporlancc of a clear definition of these words every
one must, I think, be conscious ; and if authority were required,
wc have that of Prof. Weismann himself. " I should wish to
jioint out," hcs.ays, "that we ought above all to be clear as to
what we really mean by the expression 'acquired character.'"
(" ICssays," vol. i. p. 169.)

Now, I do not profess to have read all that has come from the
pen of I'rof Weismann, and still less the whole literature that

November i, 1894]

NATURE

has gathered round the controversy ; but, after some search, I
have hitherto failed to find any definition which has satisfied me ;
and, furthermore, I do not feel quite sure that all the advocates
and opponenls of Weismann use the phrase in one and the same
meaning ; and my object in writing this, is to ask for some
assistance in finding the real and true definition of the phrase as
used by both sides in this controversy.

Let me, to assist in the discussion, refer to some of the hints
for a definition which I have been able to find.

At pp. 98-99 of vol. i. of the "Essays upon Heredity"
(English translation, first edition), Prof Weismann, having re-
ferred to "modifications which appear as the direct consequence
of some alteration in the surroundings," and to the effect of a
strange climate, says : " It is difficult to say whether the changed
climate may not have first changed the germ, and if this were
the case, the accumulation of effects through the action of
heredity would present no difficulty. For instance, it is well
known that increased nourishment not only causes a plant to
grow more luxuriantly, but it alters the plant in some distinct
way, and it would be wonderful indeed if the seeds were not
also larger and better furnished with nutritive material. If the
increased nourishment be repealed in the next generation, a
still further increase in the size of the seed, in the luxuriance of
the plant, and in all other changes which ensue, is at any rate
conceivable, if it is not a necessity. But this would not be an
instance of the transmission of acquired characters, but only the
consequence of the direct influence upon the germ cells, and of
better nourishment during growth."

This passage hints plainly at a definition of acquired charac-
ters to this effect. An acquired character is one produced by
an external stimulus acting on the organism but not influencing
the germ cells, whilst every character produced by an external
stimulus acting on the organism and influencing the germ cells
^ would not be acquired. But how are we to ascertain whether
the germ cells — not, be it observed, the embryo, but the germ
cells — have been influenced? Is there any chemical or micro-
scopic means of answering this question ? Is this influence a
physical fact capable of ascertainment, and if so, how? It
seems almost as if the presence or absence of an influence on
the germ cells respectively, were inferred from the capacity or
incapacity of transmission. But if so, I can hardly suppose
that any one would suggest that any light can be got from such
a definition, for this would be to proceed in a circle, and to red jce
the statement that acquired characters cannot be transmitted to
the following identical and useless proposition, viz. characters
which by experiment are found not to be transmitted, and are
therefore said not to aff^ect the germ cells, are not capable of
transmission, i.e. characters incapable of transmission are in-
capable of transmission.

.\t page 1 70 of the same volume occurs a passage which seems
to suggest a slightly different definition of acquired characters.
" I am also compelled to admit," says our author, " that it is
conceivable that organisms may e.xert a modifying influence on
their germ cells, and even that such a process is, to a certain
extent, inevitable. The nutrition and growth of the individual
must exercise some influence upon its germ cells." But a little
afterwards, p. 171, there occurs another passage which, if I
understand it aright, throws doubt on this conclusion ; but this
I will for the present neglect. In other passages, e.g. at p. 406,
our author refers to direct influence of an external stimulus,
such as climate, intending, I conceive, to draw the distinction
between direct and indirect influence of an external stimulus on
the germ plasma. These passages appear to me to suggest the
following propositions with reference to acquired characters,
viz.: (I) Every change produced by an influence of the organism
on its own germ cells is not an acquired character ; (2) an
external stimulus may act on the organism, and the organism on
the germ cells, and so produce a non-acquired character ; (3)
every other change produced in an organism by an external
stimulus is an acquired character.

But, assuming these propositions to be true, do they admit of
ascertainment by any appeal to physical facts? Do we know
by any examination — physical, chemical, or experimental —
what influence an organism produces on its own germ cells? If we
do, then these propositions may be u.seful, and acquired charac-
ters will be a category of changes capable of scientific establish-
ment by the appropriate means of inquiry ; but if not, then
they seem useles-, except for tlis pur|iose of propounding an
hypothesis or iheory.
At p. 169 o( tile same volume of " Essays upon Heredity," I

find Prof. Weismann saying : " .A.n organism cannot acquire
anything, unless it already possesses the predisposition to acquire
it : acquired characters are therefore no more than local or
sometimes general variations which arise under the stimulus
provided by certain external influences" ; and then he proceeds
to illustrate this by saying that the so-called "exercierknochen "
or bony growth caused by the pressure of a weapon in drilling
depends on the capacity of the bone to react on the stimulus.
"Every acquired character is simply the reaction of the
organism upon a certain stimulus."

It would not, I think, be just to consider that in the sentence
last quoted. Prof. Weismann proposes a definition of an acquired
character as being the reaction of the organism upon an external
stimulus, because many passages in our author's writings, and
certain well-known facts, seem to show that there are many
reactions upon stimuli which result in heritable characters.
Thus, at p. 406. he says: "Every one will agree with
him (Delmer) that the periodical change of leaf in tem-
perate climates has been produced in relation to the re-
curring alternation of summer and winter. This is cer-
tainly the case, and it cannot be doubted that this character
has been fixed by heredity." Heat and cold are external
stimuli, and here, if I understand rightly, they are credited with
heritable changes in the organism.

Some passages in Prof. Weismann's Romanes lecture tend in
the same direction. At pp. 10, 16, and 50 he deals with the
case of geotropism, positive and negative ; and, if I rightly
follow our author, he alleges (I) that geotropism, or the habit
of the plant to respond in some particular way to the force of
gravity, was not an original character of plants ; 12) that it
arose, or, in popular parlance, was acquired when plants be-
came attached to the ground ; and (3) that it is inherited. Now
if I apply to this what is, as I understand, taught by the Pro-
fessor, I conclude that the physical characters which produce
the habit are due to the concurrence of two things, viz. (a) the
original predisposition and (1^) an external stimulus, viz.
gravity. From this it would seem to follow that if all "ac-
quired characters " are reactions on external stimuli, yet some
such reactions are not "acquired characters."

The more I look at the matter, the more I feel it impossible
to suppose that all the reactions on external stimuli are "acquired
characters." For when I consider the vast part played by air, food,
heat, moisture, gravity, and light, all of which are external
stimuli on the development of plant life, and as I gather from
passages already cited from our author on the production of
some qualities, such as size, colour, &c., which are familiarly
known to be inherited, I feel it difficult to suppose that it can
be thought that all responses to external stimuli are to be con-
sidered as incapable of transmission. If I try to arrive at a defini-
tion by drawing a distinction between the principal and the minor
causes of a change in the organism, or by calling some things
conditions and other causes, I succeed no better ; for here I
should be introducing metaphysical distinctions. There is, so
far as I know, no physical or logical distinction between prin-
cipal and minor causes, or between cause and conditions in the
case of two or more constituent parts of a cause, each of which
is necessary, and none of which is by itself sufficient.

But this line of thought carries me further. Prof. Weismann
(" Essays," vol. i. p. 411) deals with the case of " spontaneous
characters, 5uch as extra fingers or toes, patches of grey hair,
mole«, &c.," which he says may be transmitted. But do we know
(i.e. do men of science know) that no external stimulus h.is had
anything to do with the production of, say, a mole ? It is one
thing not 10 know affirmatively that this is the case, and another
thing to know that it is not the case. Is the distinction be-
tween characters which seem to be due to an external stimulus
and characters which seem to be spontaneous, one which is
the subject of accurate scientific knowledge? Seeing that we
only know organisms when subject to stimuli, do we know what
they would be or would produce without stimuli ? Have we any
scientific knowledge of the organic world as developed entirely ah
intra and independently of any external influence, i.e. of what
plants and animals would be without light, heat, food, air? If
we have not, then the distinction relied on may be perfectly
true, but is of no value for scientific reasoning at the present
day.

Then it has occurred to me to inquire whether I can make a
safe distinction between the two kinds of change by refjtrence to
the development of the embryo. If a mole were to be found
on the arm of a child at birth, we should be moie inclined to

NO.

1305, VOL. 51]

lO

NATURE

[November i, 1894

Regard it as spontaneou;, as due to no external cause, than if it
appeared in mature life. The embryo in the case of a child is
no doubl protected from many external stimuli ; hut surely in
the case even of the placental mammalia it would not be safe to
aver that the embr)'o is protected from all external stimuli. In
the case of an insect, the greater part of its development takes
place under an exposure to external influences as complete as
that of the adult insect ; in the case of reproduction by gemm.'e
of multicellular animals, the protection must, I suppose, often
be small or nothing at all ; and in the case of the reproduction
of the lower plants from gemmae or from protonem.-i, or of the
higher plants by buds or from suckers, the embryonic condilion,
if it can be spoken of at all, is, I suppose, hardly distinguished
as regards the influence of external stimuli from any other part
of the career of the organism ; so that I find myself unable to
reach clear ground for the distinction between spontaneous and
non-spontaneous variations.

But there are passages, to one of which I have already re-
ferred, which seem to suggest that the definition should be
framed by reference to a distinction between a direct and an in-
direct inlluence, and that the definition should run thus : an
"acquired character" is a reaction of the organism upon the direct
influence of a stimulus, leaving reactions upon indirect in-
fluences to be treated as non-acquired characters. If so, what is
the precise meaning of the word "direct" as applied to the
influence ? Does it refer to the repetition of the stimulus — so
that a single change of climate would be a direct, and a repeated
change of climate an indirect influence? Or does it refer to the
supposed difference between influences operating on the somatic
part of the organism and those which the organism itself exerts
on its germ plasma ? If so, I ask how is this ascertainable as a
physiulogical fact ?

Another limitation on the proposition that the reactions of
the organism on external stimuli are acquired characters, I find
in the second volume of Weismann's " Essays on Heredity "
(English translation, p. 14), where the author, having referred
to the characters, such as shape and size of finger-nails, like-
nesses of features, bearing, gait, handwriting, which are handed
down from parent to child, goes on to add : "Characters only
acquired by the operation of external circumstancesacting during
the life of the individual cannot be transmitted." Now, hand-
writing must, I suppose, be conceived of .as a thing dependent
on external circumstances : it is influenced by the material on
which, the fluid by which, the pen or style by means of which
the act is performed ; but here the external circumstances have
operated during many generations ; so that the passage seems to
suggest these propositions, viz. the reactions of the organism
on external stimuli operating during the life of a single indi-
vidual arc not hereditary : the reactions of the organism
operating during the li%'es of two or more individuals are
hereditary. But such is not, I suspect, really the meaning of
the author ; it would be inconsistent with what he says at p. 40
of the same volume, where he says that the supposed increase
of the musical sense "in the course of generations ' by the
exercise of the art can only have occurred on the supposition
"that these modifications of an organ which are due to the
exercise during the individual life can be transmitted to ofl'-
spring" — a supposition which Prof. Wcismann says " a close
examination docs not allow us to admit."

Another limitation on the class of reactions upon external
stimuli const ituting " acquired characters "is suggested by what I
conceive to be Prof. Weismann's latest utterance on the subject,
in his work " Das Keimplasma " (Jena, 1892). At p. 514 I find
him saying — " By the term acquired characters I understand
those which do not exist originally in the germ as tendencies,
but first arise through peculiar influences which operate
upon the body or particular paits of it. They arc the
leaclions of these parts upon some external influences lying
leyond the necessary conditions of development." ' In the first
o( these sentences it seems to me that the Professor is not
so much offering a definition as announcing a theory ; for except
by the inquiry whether the character is or is not heritable, I
suppose that there is no means of ascertaining whether or not
a change in the organism is due to a tendency in the germ.

But the second sentence seems to suggest a definition of "ac-

1 It may b: well 10 give the pavtAge in the original ; " Unter crworbenen
F.iRenicNafien ver«tehe icti solche. vrclche tiicht alt Anlagen schon in Kcim

- -' — '- ■ ' . .1. -.._....'..., 1. 1-- -/^..flere Einwirkungen, die lien K-lrper

•■nAtehen. Sic ftind die Reaclionen
ilialtt der ngtIiwendiKcn Mntwickc-

junKiu^uiii^ , i,i- .. ij- ,- I ^'- ... LinHlrkiingen."

NO. 1.305, VOL. 51]

quired characters " free from many of the difficulties we have
hitherto encountered. They do not include all reactions of the
organism on external stimuli, but only such as lie beyond the
necessary conditions of development. Everything then turns
on the meaning of " necessary conditions of development."
What are necessary conditions of development ? Let us
lake a tree which has put forth its leaves, its flowers, its seeds,
in usual fashion, but which, having lost a limb by the saw of the
gardener, and has thrown out around the wound that growth of
new wood and bark with which we arc familiar. The air, the
sun, the soil are all external influences, and all necessary con-
ditions of the development which has actually occurnd, and so
was the saw of the gardener. If we take the development
which has actually occurred, every condition which led up to
it was necessary, and each was as necessary as the other. Take
the case narrated by .Sir James Paget, of a fir tree which for a
hundred and fifty years threw out successive annular growths
over the part of its trunk from which a large piece of bark had
been stripped off. (".\ddressto the Pathological Section of
the Biitish Medical .Association," iSSo, p. 15.) Were these
rings part of its development, or were they not ? If they were,
the knife or saw was one of its necessary conditions. Most
persons will reply that the saw was no necessary condilion of the
development of the fir tree, and that those only were necessary
conditions without which the fir tree could not have lived.

If we consider what are the necessary conditions for the de-
velopment of the seed of the fir tree, we can probably ascert-tin
them ; but the doctrine of evolution and the doctrine of the non-
heritability of acquired characters will carry us back further, viz,
to the primordial organism, and we must ask what were the
necessary conditions for its development.

If this organism were supposed to have in itself a preexisting
law according to which it sought development, a contingent
destiny inherent in its nature, then I can well undeist.and
how the conditions which satisfy that contingency, the circum-
stances which allow of that development might he said to be
necessary to it. But if the organism have no such law and no
such destiny, but instead thereof has only a capacity to vary in
every possible direction, and if all the course of its actual
variation be due to external circumstances operating by
means of natural selection, then it seems to me that no one
external thing can be said to be more essential to its develop-
ment than another. The germ might have found itself in a
diflTerent soil, in a different climate, exposed to different air, and
then the development of the germ would have been different.
There was no .'/ priori necessity that it should be exposed
to the particular conditions to which it w.is, in f.ict, ex-
posed, or to any other particular conditions. If, therefore,
we start from the actual development of an organism, and
look back on the past, all the conditions which have led to its
existing slate are necessary ; if we start from the germ prior to
all development, and look to the future, then no given condilion
can be said to be necessary to its development, but all are
contingent.

It is suggested that no influence lying beyond the necessary
conditions of development can .at any time have produced any
heritable character, however long may have been the course of
development. It seems, therefore, that in order to ascertain
what conditions are necessary to development, we must go back
to the amioba or ascidian or other primx'val parent of our
race, and we must conclude that those char.acters only will be
transmissible by the human parent, which were reactions on the
necessary conditions of ihe development of the prim.-eval
ancestor. Have we any scientific means of .ascertaining what
these conditions were, and so of ascertaining what characters are
now heritable? Nay, if we adopt the evolutionary hypothesis,
and believe that at least all existing animal organisms have
sprung from a single parent, do not the diversities of Ihe exist-
ing forms show that no one set of external circumstances were
necessary conditions of development, but that the conditions
consistent with development were infinite, or all but infinite, in
number?

A further diflicully arises in my mind from a passage on the
next page (p. S'S)i where I find our author mentioning
wounds and mutilations as constituting one category of acquired
characters. It is difficult to reconcile this with Ihe statement of
the Professor, in several passages, that acquired characters
are reactions of the organism ; for surely a wound is not a
reaction of the organism, whilst the growth of the organism
consequent on the wound— ^■.j'. the growth of new wood

November i, 1894]

NA TURE

II

and bark round the stump of a branch sawn off, is a reaction of
the organism on the action of an external influence. It seems,
therefore, fair to suppose that when our autlnr spealcs of a muti-
lation as an acquired character, he means the growth of the
organism consequent upon the mutilation. 15ut if so, a
■difticulty appears to arise ; for the tendency to repair a wound is
heritable, and therefore it seems difficult to suppose that the
Professor would treat of it as not heritable. It may be said
that the parent has the actuality of the repair, the child
only the possibility of repairing ; bat this is, I suppose, all
that can ever be e.\pected of inheritance as applied to
-contingent reactions — i.e. reactions which only arise under
peculiar circumstances. There can, I suppose, be no more
■characteristic heritable reaction than that of the pollen on the
ovule, and of the ovule on the pollen ; these reactions have taken
place in the parent plant, but in the offspring they are
originally potentialities, tendencies, contingencies, and they
are converted into facts in the event, and in the event only,
of the meeting of the pollen and the ovule.

Or take, again, the secretion of the gastric juice in response to
the presence of food in the stomach. The parent has taken
food, and the reaction has taken place; but the infant inherits,
I suppose, the capacity to secrete and not the counterpart of the
actual secretion of the parent.

It would seem that there is no essential difference between
these three cases. The parent transmits the power to repair
ji wound, but not the actual reparation of a wound : it t.ansmits
the power of fertilisation, but not the fertilised ovules : it
transmits the power to digest, but not the already secreted
gastric juice.

The emphasis which Weismann has laid on the case of wounds
and mutilations would suggest that his doctrine might be thus
paraphrased : when an organism is endowed with a capacity, or,
to use his word, a predisposition, to react in response to given
stimuli, and has so reacted — then what the organism transmits
k> its progeny is the capacity or predisposition, and not the
actual result of the reaction.

It is impossible to doubt that some characters of an organism
are hereditary ; that others are not, and that the ascertainment
■of the dividing line between the two classes is of the highest
moment to the study of biology ; and to Weismann we owe a
■debt of gratitude for having called pointed attention to this
matter. I have at times been tempted to wish that men of
science had applied themselves to ascertain the two categories
of characters, and then by a careful induction had proceeded
•to learn the law of heredity without regard to any hypothesis
or theory — without reference to germ or soma. But this is
not the course which in fact has been taken ; and therefore it
«eems highly necessary to inquire what is the precise meaning
of the terms of the proposition affirmed by the one side, and
denied by the other.

I conclude this, I fear, too lengthy paper with two questions :
i.\) Are the conditions which I have suggested as essential to a
good definition correct ones ; if not, in what are they erroneous?
(2) What is the true definition of the words "acquired
characters '' in the present controversy which satisfies these
<:onditions? Edw. Fry.

Discontinuous Motion.

The old theory of the motion of solid bodies through a
ftictionless liquid supposed that the li(iuid flowed according
to the electrical law of flow. This theory was found to be un-
satisfactory, because it makes the pressure negative when the
velocity of the solid exceeds a certain critical value.

The theory of discontinuous motion removes the above
objection, but is open to others of a different kind. Assuming
for the sake of argument that the two theories give correct
results when the velocity of the moving solid is respectively
Jess and greater than the critical value, the theory of discon-
tinuous motion ought to be capable of explaining the transition
from one kind of motion to the other, and how and why it is
possible for a vortex sheet to be called into existence when the
critical value of the velocity is exceeded.

Although vortex sheets and other motions involving molecular
rotation cannot be generated in a frictionless liquid by a con-
servative system of forces or by operations perlormed on the
■boundary, yet it is easy enough to produce such motions by
ordinary mechanical agencies. If a mixture of ice and water
be stirred up and the ice allowed to melt, the liquid will

MO. 1305, VOL. 51]

acquire molecular rotation owing to the presence of the particles
of melted ice, even though it is absolutely devoid of viscosity.
So also if liquid at rest were separated by an indefinitely thin
horizontal plate, and the upper liquid were set in motion with
horizontal velocity V and the plate were removed, the surface
of separation would be a vortex sheet. But the production of
motions of this kind requires methods of a somewhat artific iai
character, and it is difficult to see how they could be set up by
a solid whose velocity is allowed to increase gradually from zero
to some magnitude greater than the critical value. In fact, I
entertain very little doubt that the final motion of the liquid
would be quite different from what the theory of discontinuous
motion would indicate.

There is, however, a further point, for there are strong
grounds for believing that vortex sheets are unstable. No
general proof of this proposition appears as yet to have been
given, but in every case that has been examined the theorem
has been found to be true, (i.) when the liquids on either side of
the sheet are identical, (ii.) when the densities of the two
liquids are different, but no bodily forces such as gravity and
the like are in action. If, therefore, steady discontinuous
motion existed at any particular instant, the probabilities are
that the motion would be unstable, and the region of dead
water in the rear of the moving solid would break up and be
changed into a region of turbulent motion. The pressure in
the rear of the solid due to this turbulent motion would be
different from that of the dead water, and it is therefore not
surprising that the theory of discontinuous motion should
furnish results which do not agree very well with experiment.

We must also recollect that a frictionless liquid is an ideal
substance which does not exist in nature. .\ll fluids are more
or less viscous ; and it is just at the point where the pressure
would otherwise tend to vanish and change sign that we should
anticipate the effect of viscosity would appear, and prevent
this stale of things from taking place ; and I believe that many
of the difficulties which have arisen in connection with this sub-
ject are due to the fact that the effect of viscosity has been over-
looked. A vortex sheet cannot exist in a viscous liquid ; and if by
any artificial means one were produced, it would immediately dis-
appear, and molecular rotation would be propagated into the sur-
rounding liquid. On the other hand, in a viscous liquid, molecu-
lar rotation requires no artificial means for its production ; for a
viscous liquid cannot move without molecular rotation, except
in the single case in which the liquid moves like a rigid body
having a motion of translation alone. In all other cases, il
irrotational motion existed at any particular in -tant. the motion
would immediately cease to be so, and molecular rotation
would instantaneously be generated.

Unfortunately the equations of motion of a viscous liquid
are so intractable that very little progress has been made in
applying them to the solution of hydrodynamical problems.
By means of Oberbeck's solution [Borchariit'i J otirnal, yo\.
Ixxx. ) for the steady motion of translation of an ellipsoid in
a viscous liquid, it can be shown that the above difficulties do
not arise when viscosity is taken into account ; but since the
integration of the equations of motion proceeds upon the
assumption that the squares and products of the velocities may
be neglected, the solution is inapplicable except in the case of
slow motions like those produced by the small oscillations of
pendulums. The solution gives no information as to what will
happen when a disc is moving through a liquid with a velocity
of several feet per second. A. B. Basset.

Fledborough Hall, Ilolyport, Berks.

Capacity for Heat.

In the course of some writing upon which I am now engaged,
I have constantly to refer to the capacity for heat of certain
substances as compared ■.villi the capacity for heat of an cqtuil
volume of water.

The phrase given in italics is a most clumsy one, but I know
not how (accurately) to convey the same idea in a shorter way.
" Cafacilyfor heat of unit volume" has been suggested ; but I
think that a little reflection will show that it does not express
accurately the exact meaning.

Specific Heat X Specific Craiity gives the numerical value

required, but cannot be regarded as a definition. There can be

no doubt but that a concise expression is wanted. In calori-

metry it is often of greater importance to the experimenter to

onsider the capacity for heat of volumes rather than the capacity

12

NA TURE

[November i, 1894

of masses. In the course of a communicalion which I made to the
Physical Socieiy of London, at their last meeting, I appealed to
the Fellows present lo supply me with the missing phrase. In the
discussion which iollovved the paper, thi<; matter was only inci-
dentally referred to : but, aUhoagh I think that there wa4 a
general agreement as lo the want, unfortunately the meeting
closed without coming to any conclusion as to the best method
of supplying the deficiency.

Will some of your readers help me in this matter?

12 Park Side, Cambridge. E. H. GRIFFITHS.

The Swallowing of One Snake by Another.

The snake incident, described in Nature, October 25 last,
page 620, as having occurred in the reptile-house in the Zoo-
logical Society's menagerie, recalls to my mind two similar
cases, recorded in the same periodical, vol. xxx. July 3, 1884
(".\ Cannibal Snake," by E. H. Evans), and July 31, 1SS4
(" The Swallowing of One Snake by -Another," by C. K. Osten-
Sacken). The first case was observed in Java, the other was wit-
nessed by me in Washington, D.C. In the latter case one of the
snakes, although three-quarters of its length had already been
engulphed in the other, succeeded in getting out, apparently
unhurt, as it remained alive and well in the cage a long time
afterwards.

In the Figaro, July 26, 1894, I found still another instance
of the same kind, which happened in the Jardin d'.Vcclimata-
tion in Paris. A large snake, while attempting to swallow a
rabbit, was interfered with by another one, and passed with the
rabbit into the body of its comrade of captivity ("L'un des
deux passa a la suite du lapin dans le corps de son camarade de
captiviie"). C. K. Oste.n-Sacken.

Heidelberg, Germany, October 28.

O.V RECENT RESEARCHES IN THE
INFRA-RED SPECTRUM}

T PRESENTED to the Association in 1882, at
*■ Southampton, an account of some researches made
by means of the bolometer, in the infra-red spectrum,
formed by a glass prism ; but though these labours have
continued wuh occasional intermission during the past
twelve years, it is for reasons, which will be explained
later, only within the past three years that any notable
advance has been made, and only within the past twelve-
month that such a measure of success has been attained
as justifies the present communication.

This is not the time to give any historical account
of discovery in the infra-red, but all those interested
in the subject know that the first investigator here
was Sir William Herschel, whose observations con-
sisted essentially in finding that there was something
which the eye could not see in a region which he pro-
po-cd to call the " thermometric spectrum." His dis-
tinguished son. Sir John, made a curious anticipation of
later discovery by indicating, though crudely, that this
invisible heat was not uniformly distributed, and a similar
conclusion was reached in an entirely different manner,
through the thermopile, by the too early lost iMelloni. So
ignorant, in spite of these investigations, of those of the
elder Draper and of the elder IJecqucrel, were we till
lately, that when,'|uite within my own recollection and
that of most of you, Lamansky in 1871 published, from
his observations with the thermopile, a crude little illus-
tration showing three inequalities in the energy curve,
universal attention was e.tciled by it among those
interested in the subject.

Among other minds my own then received a stimulus
which turned it in this direction, and having, as it seemed
lo me, exhausted the capacities of the thermopile, I
invented an instrument for continuing the research,
which was afterwards called the bolometer, and with
which, in |8<|, at an altitude of 13,000 feet upon Mount
Whitney, I found spectral regions hitherto unreached,
and whose existence had not been suspected.

> A paprr rcirl lo Section A of the Itrilii,!) Association, at the Oxford
nc ting on AuKutt 11, hy .S. P. l.angley.

NO. 1305. VOL. 51]

I returned with a strong impression of the prospective
importance of this discovery, and laboured at the .Alle-
gheny Observatory in improving all portions of the new
method of research, especially of the bolometer and its
adjuncts, with the twofold object of obtaining greater
sensitiveness to heat, and greater precision in fixing the
exact point in the spectrum where the change of heat
originated. With the former object such a degree of
sensitiveness was at that time reached, that the bolometer
indicated a change of temperature of ,,^|iV,,jo of <i degree
Centigrade, and with the latter, such precision that it was
possible to fi.x the relative position of a line, not
merely with a possible error of a considerable fraction
of a degree, such as Lamansky's determination is
evidently subject to, but with a certainty that the error
would be within a minute of arc. The range of the
apparatus in wave-lengths was almost unlimited as com-
pared with any other process, and both its sensitiveness
and its possible precision seemed to be at that time
notable as compared with previous methods, for a great
advance was made on anything done before with the
thermopile, when the presence of the well-known " D "
line of sodium was rendered sensible (though barely
sensible), even as a siiis^le line, by the change of tem-
perature. The sensitiveness was also, as has been said,
accompanied with the possibility of unusual precision.
The results of this labour were laid before the British
Association in the communication already alluded to,
and which exhibited ten or twelve inflections of the
curve in the portion till then almost unknown, which
extends from a wave-length of of \y. to a wave-length of
nearly jw, at which point the glass prism then used
became wholly opaque to radiation. The positions of
these inflections were fixed with a precision quite impos-
sible to the thermopile, but this exactness was only
obtained in practice by a process so slow as to be almost
prohibitory ; and with this apparatus the writer person-
ally made in those earlier years such a number of obser-
vations as he h.irdly likes to recall, so disproportionate
did the labour inherent in this method seem to the final
result.

The justification of this labour seemed to lie in the fact
that it does not appear that photography has ever ren-
dered anything much below a wave-length of i^ -any-
thing, at least, which has been reproduced for publication
in a way which gives confidence that we are in touch
with the original. The processes which involve the use
of phosphorescent substances have given some indications
of lines considerably below i/j, but it is safe to state that
the work which has just been referred to as communi-
cated to this .Association in 1882, presents almost the only
indications which we have possessed, even up to the
present time, about the lower infra-red solar spectrum.

Now the curve which was given, even in the later
Allegheny observations made with the rock-salt prism,
contained but a dozen inflections below the wavelength
of l'5^, and these inflections, with their correct prismatic
and wave-length positions, represent, I think, most of our
present knowledge in these regions even today.

To understand the method by which there were attained,
but only at this great cost of labour, results till then un-
reached, it may be repeated that the bolometer had been
rendered more sensitive than the thermopile, but that it
was capable of being pointed and its position in the
spectrum being measured, only by a tedious process
which has been exchisively used till lately (but which that
presently lo be described advantageously replaces).
Whichever process is used, when the bolometer thread
touches a cold line in the spectrum (since what is black
to the eye is cold to it), a larger current llows through the
galvanometer, and the spot of light marking the needle's
motion is deliecled through a certain number of degrees.
From this ])oint forward, the new process, whose re-
sults I am about to have the pleasure of bunging before

November i, 1894J

NA TURE

ou, differs widely from the old. In the old, two ob-
servers at least are engaged : one, who notes that reading
of the micrometer or of the vernier, which fixes in angular
measure the exact part of the spectral region whence
(though nothing is visible) a thermo-electric disturbance
has proceeded; and another, who simultaneously notes
through how many divisions of the scale the spot of light
from the galvanometer mirror is deflected by the same
electric disturbance. The process may be compared to
a groping in the dark, and it was only by these means
that the considerable inflections of the energy curve
much below the region about l/x were then fixed by
the bolometer, by being gone over again and again, with
what seemed almost interminable repetition, and which
did in fact call for over a thousand galvanometer readings
to obtain the position and amount of each single inflection j
of the energy curve, with the degree of accuracy which i
was then obtained, and which was shown in the former
memoir.

If it took two years to fix the position of twenty lines
Ijy this process, it would take two hundred years to fix
two thousand, supposing they existed, and it became
evident that if the bolometer continued to be the only
means available, new and more effective methods of
•ising it must be found.

New Methods.

.About ten years ago a plan was first studied, which
has ever since been maturing, by means of which this
work could be carried on, not only with far greater
rapidity, but with greater certainty, and by an automatic
process. The idea in its original simplicity is very easily
understood.

In the old process, just described, the deflection of a
spot of light upon a scale was read by one observer,
while another read simultaneously the position in the
spectrum of the cold band, or line, which caused the
thermo-electric disturbance.

Now, in imagination, let us take away both the
observer at the circle and the one at the galvanometer,
and, in the latter case, remove the scale also, and put in
its stead a photographically sensitive plate. As the
needle swings to the right or left, the spot of light will
trace upon the plate a black horizontal lire whose length
will show how far the needle moves, and how great the
heat is which originated the impulse. If this be all,
when (under an impulse originated by the movement of
the spectrum over the bolometer thread) the needle
swings a second time, it will go over the same place ;
but if the plate have a uniform vertical movement, pro-
portional to the horizontal movement of the spectrum,
the combination of the two motions of the needle and the
plate will write upon the latter a sinuous curve which will
be, in theory at least, the same as the curve formerly
deducible only with such pains from thousands of such
galvanometer readings.

If we suppose that the movements of the invisible
spectrum over the bolometer thread are controlled by
clockwork so that this spectrum is caused to move
uniformly, and that three movements are, by accurate
mechanism, rendered absolutely synchronous with those
of the moving plate, it is clear that we shall be able to
readily deduce from the photographic curve traced on
the latter, not merely the amount of the heat, but each
particular position in the spectrum, of the thread of the
bolometer, which alone can correspond with any given
inflection of the curve.

Thus simple is the theory ; but no one had better
occasion to know how difficult the practice would be,
than myself

The researches by the old method, and the early
attempts to improve them, were interrupted by my
acceptance in 1SS7 of a position which implies the
administrative charge of different branches of the public

NO. 1305, VOL. 51]

scientific service and of duties largely incompatible with
original research. What time could be spared from these
was, however, partly employed in elaborating the plan
of investigation just referred to. An appropriation had
been asked of Government for the establishment, on a
modest scale, of an astro- physical observatory in
Washington, whose first work should be the investiga-
tion of the whole infra-red solar spectrum, by some
means which would open that great region to knowledge.
It had been asked of Government because it seemed that
such knowledge, if attained, might teach us facts about
the sun and the absorption of its rays by the terrestrial
atmosphere, which there was ground to hope would
ultimately lead to results of such importance as to justify
this national aid.

These observations were resumed in 1890 on the new
system, with the aid of the Smithsonian Institution,
which provided larger and more efficient apparatus,
whose design embodied the results of nearly fifteen
years' study of these subjects.

Pending the provision of a suitable observatory build-
ing, an inadequate and temporary one was erected in
the Smithsonian Park in Washington, to shelter the
apparatus, presently to be mentioned, with which it was
designed to commence work while making provision for
more permanent scientific quarters (which I may add are
still lacking).

Apparatus.

The Foucault siderostat, perhaps the most powerful
instrument of the kind existing, was originally made by
Sir Howard Grubb, of Dublin, from my indications ; but
its dispositions have since been considerably modified.
A beam from its 20-inch mirror is conveyed through
the slit of a horizontal coUimating telescope having
a rock-salt objective of nearly seventeen centimetres
aperture, and of ten metres focal length, to the prism
or grating. The prism is of rock salt of correspond-
ing dimensions, worked (by Brashear) with the pre-
cision of, and presenting all the external appearance of
one of flint glass. It is mounted on a massive spectro-
bolometer (as the instrument which supports the prism or
grating used in producing the spectrum is called). This
instrument includes a large azimuth circle, over the
centre of which the prism is placed, and it also carries the
bolometer, which registers the spectral heat. The focal
lengch of the image-forming lens, or mirror, is in this
instrument much greater than in the first one used, and
all parts of the apparatus are correspondingly increased
in size and stability. The most important and novel
feature is, however, the mechanical connection of the
large azimuthal circle carrying the prism, with a distant
photographic plate, susceptible of vertical motion, and
which latter takes the place of the scale formerly in front
of the remote galvanometer, both circle and plate being
moved by the same clockwork, which is of such steadi-
ness and precision as to make the two movements as far
as possible perfectly synchronous.

To fix our ideas, let us suppose that the slow-moving
azimuthal circle carrying the prism revolves through one
minute of arc in one minute of time ; in which case the
spectrum will move horizontally across the vertical bolo-
meter thread at a proportional rate. Now, if the same
mechanism which causes this circular motion of the prism,
and of the spectrum, of one minute of arc in one minute
of time, causes the photographic plate to move vertically
before the galvanometer mirror at the rate of one centi-
metre of space in one minute of time ; if there be no
allowance to make for changes of temperature in the prism
or for like corrections, if the mechanician has done
his part in such perfection that everything works as it
should, it obviously follows that, under such conditions,
during every second of this minute a portion of the
spectrum represented by the small quantity of one second
of arc, will have glided before the bolometer thread, and

14

NATURE

[November i, 1894

that during this same second the plate will have been
lifted automatically through one-sixtieth of a centimetre
of space.

This is one relationship of time and space in actual use
here, though others may be established by the use of the
change-wheels with which the apparatus is provided.
The essential thing is that the plate shall show with great
precision, and even on simple inspection, not only the
inflections of the energy-curve there written down, but the
exact relative position in the distant spectrum which the
bolometer thread occupied at the moment it caused the
disturbance. In the case assumed, for instance, if we
suppose that the record on the plate commences with the
part of the spectrum whose angular value is 40 , then,
since : millimetre corresponds to 6 seconds of arc, and
so on, the e.xistence of an inflection on the plate at 30
centimetres, 3 millimetres and seven-tenths of a milli-
metre, would show that the disturbances originated at
the point in the spectrum corresponding to an angular
measure of 40" 30' 22 'a.

If the arm which carries the bolometer is n metres

long, and if the thread of the bolometer is - metres in

diameter, the angular value of the bolometer thread is

— . At present the linear width of the bolometer thread
mn

is not very materially less than formerly, but it is used with
a longer arm, and its virtual width is accordingly less. In
present actual practice (to use round figures) the optical
arm carrying the spectrum across the bolometer, is five
metres in length ; and if the bolometer thread be one-
twentieth of a millimetre in width, its angular value is
evidently jsoVuis o*^ 'he radius of the circle in which it
moves, or a little over two seconds of arc. AVhen the
heat is distributed over so large an area, that part of it
which falls on a thread of given diameter is, of course,
proportionately less, so that the greater precision of
measurement demands a more sensitive construction of
the bolometer, as well as a more accurate mechanism for
pointing it. Improvements have accordingly been in-
troduced in the construction of the bolometer, and a
need for greater sensitiveness in the galvanometer has
necessarily gone with them. This increased sensitive-
ness has caused increased liability in the latter to both
systematic and accidental perturbations, and the elimina-
tion of these has been found the most formidable diffi-
culty of the whole process. It has been effected, largely,
by placing the whole apparatus under constant tempera-
ture conditions.

I take pleasure also in acknowledging the advantage I
have found in using both Prof. Hoys's quartz threads and
the extremely small mirrors which he, 1 think, first advo-
cated in connection with the well-known form of galvano-
meter due to Lord Kelvin. These and other collective
improvements made in the bolometer and in the galvano-
meter, have now made the former sensitive to changes of
temperature in its strip which are demonstrably less than
I 1,000,000 of a degree Centigrade.

These are the principal pieces of apparatus, though I
should mention that a method has been found by which
the very large salt prisms used can be preserved in per-
fect polish while exposed to all the usual casualties of
observation. The actual prism in most frequent use was
made from a block of salt exhibited at the World's F'air
by the Russian Government, and presented to the
.Smithsonian Institution by its Commissioners. It is
about eighteen centimetres, or over seven I'.nglish inches,
in height.

Before entering upon a description of the results
obtained, I desire permission to speak of the aid I have
received from the gentlemen whose assistance I have
been fortunate in securing; first, to Dr. Ilallock, then to
Prof. Hulchins, Mr. Hubbard, and Mr. C. T. Child, and

NO. 1305, VOL. 5IJ

lately to Mr. F. L. O. Wadsworth and Mr. R. C. Child J
the imprint of the labours of the two latter gentlemen
being upon almost all the details of the more recent
work.

Results.

Let us recall that the infra-red spectrum from a rock-
salt prism, such as that used here, is extremely con-
tracted as compared with one from flint, and still more
contracted as compared with the wave-length scale. The
portion of the spectrum presented by photography
reaches a little below the band whose wave-length is
about i/x, and this was asserted by one of the most
eminent living authorities on the subject (Dr. John W.
Draper), when the writer commenced this work fifteen
years ago, to be the absolute end of the heat spectrum.
The writer has, however, since carried his investigations
by direct measurement to five or six tmies this wave-
length, and by indirect measurement much farther still,
though what is here now exhibited does not go beyond
a wave-length of about 4/i. The invisible heat spectrum
of a 60" rock-salt prism through this great wave-length,
includes only somewhat less than two degrees of arc, and
the first of these degrees contains the greater proportion
of the energy.

On referring to the illustrations exhibited to the
Association in 1882, or even to later publications of
results obtained by rock-salt prisms, though with the
old method, it will be seen that there are shown in the
latter publication about a dozen measured inflections of
the energy curve below i/i'5, and it may be remembered
that this curve was obtained only by two years' assiduous
labour.

We have now before us three energy curves obtained
by the new method, each exhibiting the whole infra-red
spectrum under examination, with about a hundred
inflections. These curves are nearly, but not exactly,
similar.

The three were obtained in the same day, each from
an entirely independent observation, so that each has
given, in a fraction of a day, many times the results
previously obtained by two years of labour, and, as it will
be later shown, has given these results with a notable
gain of accuracy.

But this is not all. These three curves have been
taken with a rapid movement of the clockwork and a
brief swing of the galvanometer, so as intentionally to
suppress all minor inflections and to introduce only the
leading features of the spectrum, as shown in eighty or a
hundred of the leading inflections (lines), or groups.

This new bolometric method has, however, as will be
shown later, a capacity of resolving these into nearly
twenty times that number, the minor inflections having
been thus designedly suppressed here at first, to better
show the character and position of the principal ones. All
these energy spectra, by the new as by the old method,
are, of course, subject to the slight changes due to invisible
clouds constantly passing before the sun, which, with
the change of the sun's altitude, and of the consequent
lengthening path of its rays, prevent any one of them
from being exactly like the other ; while, at the same
time, everyone here may satisfy himself by direct
inspection of the results before him, that there is scarcely
any single one of their inflections which is not reproduced
in the other two, in exactly the same place, though
probably not exactly in the same degree ; and when we take
different spectral traces, made at different hours of the
day, and even on diflerent days of the month — traces
which are absolutely independent of each other — and
superpose them, experience shows that we may expect to-
see such an agreement as that in the three here chosen
at random for illustration, or in the more detailed one.
where the relative probable error is less than one second
of arc. Three such traces only are here given (to prevent
confusion), but if we follow these coincidences through

November i, 1894]

NA TURE

not three, but ten or more plates, we may well judge
(since there seems no possibility here of systematic error)
that a result, which all confirm, is reliable, and that, on
the other hand, a single inflection on one plate, which
the other nine unite in repudiating, is due to some
fortuitous cause.

But there is still a higher certainty to be obtained, by
a method independent even of comparison or the
exercise of judgment. It is founded on the well-
known process of composite-photography, where, in
photographing the successive members of an assem-
blage of persons, having similar general characteristics,
as of race, character or education, the individual
disappears, and the normal type alone remains. In
order to apply this method to such results as ours,
however, another step in the process must be intro-
duced, and this is an interesting one, for the energy
curve itself, however valuable, is a comparatively un-
familiar method of showing variations in the energy,
which we are all alike used to seeing in the visible spec-
trum given by linear representations, and not by a system
of inflections.

In describing this new step, which is to give us a
linear spectrum in addition to the original curve, it will
be desirable to also give evidence of the statement now
made, that the present method is capable of recording
far minuter inflections than those shown in the curves
here exhibited, which, as has just been stated, have been
taken only for the purpose of illustrating such more im-
portant features, as can be seen and verified by the
audience, and especially for showing the agreement of
independent observations. The evidence of the capacity
of the apparatus to show this detail will best be illus-
trated by applying our purely thermometric method to
some well-known lines in the visible spectrum, such as
the familiar " D '' lines of sodium. I have already stated
that ten years ago the bolometer was barely able to dis-
tinguish this as a single line. At the present time our
little thermometer, as you here see, now shows not only
the two "D's" as separate lines, but the nickel line
between them. First we have the complex energy curve
(Fig. i), where we see successively the inflections due to
the motions of the galvanometer caused by the cold m D,,
then to the smaller chill from the nickel line (aided per-
haps by that from some of the close atmospheric lines),
then the chill from Dj.

Immediately below this curve is the more familiar linear
representation of the same subject (Fig. -)■ Now this
linear representation, it is most important to observe, has
been obtained, not by drawing, but by the subsequent
application to the curve of an automatic process, by means
of which its indications are reproduced by photogravure,
as separate lines, while by the same automatic process
the most complex spectral curves can be rendered into
their linear equivalents.

I have no space to enter here on a description of this
process, further than to say it is effected by means of a
systematically distorted image of the curve, obtained by
a special combination of spherical and cylindric lenses.
You will see, on minute inspection, that the inflections
of the galvanometer curve have been slightly " loaded,"
to produce a more ettective contrast of light and dark.
Except for this, which can in no way affect the position
of a line, but only its intensity, the whole process is as
absolutely automatic as any photograph of the visible
spectrum.

This thermograph of the " D " lines has been chosen
to indicate the grasp of this new thermometric method,
by applying it to the test of an object in the visible
spectrum, with which every physicist here is doubtless
familiar. He may then be invited to recall that the
distance between the " U's " in a rock-salt Oo-degree
prism is about eleven seconds of arc, and to observe that
two lines about half this distance apart are here shown

NO. 1305. VOL. 51]

as sharply divided by this thermal method, as, for
instance, are the components of the double star
a Geminorum by a three-inch achromatic. Obviously,
then, our method could indicate the existence of two
lines, little, if any, more than one-quarter the distance
between the " D's." Lines 3' or less apart can then
evidently be indicated by this method, even in its present
stage of development.

And now, returning to what has been said about the
evidence obtainable as to the perfect coincidence of
these inflections in different energy curves obtained at
different times, and to the consequent evidence that each
inflection so given is real, and not the product of an

Fig. :.

t'.

accidental variation in the curve, we may conceive that
from any number of such independent curves, any
number of such linear representations of the spectra
have been obtained ; for example, that ten such linear
representations of the whole spectrum as are nere given
of the U lines only, have been so found from ten com-
plete energy curves taken on as many different days.
From these ten linear representations, by the well-known
processes of composite photography, one final photo-
graph of the spectrum is formed, and on this it is
evident we may expect to find only what is permanent
and not what is accidental, granting that a rare accident
may have introduced an occasional abnormal deflection.
Xow, considering that the part of the infra-red solar
spectrum of rock-salt under review extends through

i6

NATURE

[November i, 1894

nearly two degrees, or 7200 seconds, and that we have
just seen by the illustration of the D lines that lines
3 inches apart can be thus divided, we may see for
ourselves that, at any rate, over 2000 lines, if they
exist, can be mapped. But these lines do exist, the
whole of this new region being apparently as inti-
mately tilled by them as the visible spectrum by the
Fraunhofer lines. In further evidence of this, here
is a portion of the lower spectrum in the comparatively
unknown part extending from X = r4/i to \ = i'2\i. in-
cluding the great band 2 shown as a single inflection in
my first communication to this Association, but here re-
solved into thirty or more subordinate lines (Fig. 3). This
illustration includes a part of the new region discovered
on Mount Whitney in iSSi ; and in the small portion
here exhibited, you may see that about 200 lines are
discriminated.

I am now trj-ing to bring what may be called the
first stage of the long labour, a portion of which is
here described, to a close, this first stage consisting

the expense of the invisible, nor even on such a log-
arithmic one as that proposed by Lord Rayleigh, but on a
conventional scale, which 1 will ask you to tolerate, as it
is simply meant to show the actual extent and importance
of the region covered here as compared with that known
to Newton. In this illustration, with which I close my
remarks, the mean dispersion throughout the invisible
rock-salt spectrum, as far as 4^1, is taken as the standard,
and both spectra are laid out on that common scale. On
the left is the visible spectrum known to Newton ; next
this, is the region known through photography, now ex-
tending a little beyond the band, /jot, which marks what
at the time these researches were commenced, was con-
sidered by the then most distinguished investigator, in
the infia-red, the end of the heat spectrum. Beyond,
and on the right, is a part of the new regions of the spec-
trum developed by the bolometer, and of which charts
may be shortly expected on the scale of which a speci-
men in detail has just been shown.

1 cannot close this statement without expressing the

I

I I !

lii

KiG. 3. — iiulograph of the portion of the infra-red Eolar spectrum lying telw.-cn wave-lengths i j/x and 2*?fA.

chiefly in the discovery of, and mapping the relative
positions of new spectral lines.

I will only refer to what it seems to me the second
part of this work is likely to be, and to the different kind
of interest which may not improbably belong to it, from
that which belongs to this, the first.

We are thus far in the position of early students of the
visible spectrum, who simply drew the lines they saw,
without inquiring into their meaning. Nevertheless, to
have discovered and mapped a great number of these
lines is only a beginning, for their real value lies in
their interpretation, and this is still chiefly to come, |
As to the possible importance of this interpreta-
tion, it is not enough to remind ourselves that three-
quarters of the whole energy of the sun exists here,
and not in the upper spectrum. We must remember
also that while, as a rule, in the upper and visible spec-
trum a great proportion of the lines are caused by
absorption in the solar atmosphere, and a perhaps smaller
portion by telluric absorption, here, on the contrary, we
are led. by everything we already know, to expect that
the great telluric absorptions on which meteorological
predictions and other immediately practical interests
depend, may be expected to be found, and it is on the
comparison of these energy curves taken at different
periods of the year, and at different altitudes of the sun,
that those who are engaged in the work see good cause
to hope for important results in the future.

Before I conclude, let me present a collective view of
the field in which work has been going on in these
later years at the Smithsonian Observatory, on the same
scale, with the visible spectrum. I say "on the same
scale," meaning, not on a wave-length scale, which ex-
pands the invisible at the expense of the visible, and not
on a prismatic scale alone, which expands the visible at

NO. 1305, VOL. 51]

gratification with which I have laid it before the s.-ime
body that listened to that made on the same subject
twelve years ago, or my sense of my good fortune, in
doing so before an audience in which 1 recognise many
of the same eminent men who so kindly received that
first presentation of these researches.

THE TREA TMENT OF DIPHTHERIA
ANTI-TOXIC SERUM.

BY

FOUR years ago Prof. Behring published his remark-
able paper '' On the mechanism of immunity ag:ainst
experimental diphtheria in animals.'' In this memoir the
author stated that it was possible to immunise animals
against the diphtheria b.icillus by the injection of cultures
attenuated by heat or the addition of i in 500 tri-
chloride of iodine to the cultivating medium. The same
result could be obtained by the inoculation of the pleural
exudation of animals dead of experimental diphtheria,
or by the injection of chemical compounds, such as
trichloride of iodine, after inoculation of virulent diph-
theria-bacilli.

liehring's most important discovery, however, was
that the serum of animals immune against the bacillus
of diphtheria and its poisons had the power of " destroy-
ing" in vitro and in the animal body the chemical poisoix
secreted by this bacillus ; and that animals, after a mortal
dose of <ii|)htheria poison had been injected, could be not
only immunised, but actually cured, by the introduction
into their system of the serum of animals immunised
against the specific bacillus and its poisons. In a further
series of researches he found that the serum of such
animals possessed this power to a most remarkable and

November i, 1894J

AVi TURE

17

almost incredible degree, and that the therapeutic value
of this serum increased up to a certain extent with the
amount of diphtheria-toxine which had been introduced
into the system ; whilst, on the other hand, the same
toxine injected in too large quantities might cause the
serum to lose its " anti-toxic" property.

Behring afterwards immunised large animils, such as
sheep, horses, &:c., against diphtheria by the repeated
injection of diphtheria-toxine, and he observed that their
serum was of great value when injected into human beings
suffering from this disease. Before proceeding, however,
it may be convenient to discuss these statements at some-
what greater length, and illustrate them by an account of
a few experiments.

Let us draw some blood from a horse which has been
thoroughly immunised against diphtlieria, and decant
the serum after its separation. We now take a filtered
diphtheria culture, a given quantity of which we know to
prove fatal to a guinea-pig of a certain weight in a certain
number of hours. Let us divide, for instance, 5 c.c. of
this filtered culture into five doses, and inject i c.c. mto
a guinea-pig (A) weighing 500 grammes without the
addition of any serum. Four other guinea-pigs of the
same weight as the first receive the same amount of
toxine and 'l c.c, 'oi c.c, 001 c.c, '0001 c.c. of the horse's
serum respectively. The first guinea-pig (A) will die in
less than twenty-four hours, but of the others, the three
first will recover without any symptom of illness ; whilst
the last, which has received "oooi c.c. only, will probably
die after some delay. We know, then, that the dose of
serum which will protect a guinea-pig of a given weight
against a known amount of toxine injected at the same
time as the serum, lies somewhere between 'ooi c.c. and
"OOOI c.c, and, by further experiments, the exact dose
may be accurately determined. In this way we may form
an idea of the strength of the serum, but we must always
remember that the data thus obtained are but approxi-
mate ones.

The curative serum may be introduced into the animal
the day before the toxine is injected, but, in that case, a
much larger quantity of serum will be necessary to pro-
tect the animal. If the serum be inoculated at the same
time as the toxine, and in a different part of the body,
the quantity of serum must also be increased if the
curative effects are to be apparent. If, some time is
allowed to elapse between the injection of the toxine and
that of the curative serum, the quantity of serum — in order
to be effective — must be proportionately greater ; but I
have seen animals recover when the injection of the
curative serum had been delayed eleven hours after the
introduction of the toxine, which proved fatal to the
control animals in 28-4S hours. In this latter case the
dose necessary to cure was 5000 times that sufficient to
immunise when the serum was injected with the toxine.

Can any opinion be formed as to the mechanism
in which this serum exerts its action.' The first ex-
planation which suggests itself is that when the curative
serum and the toxine are mixed together in the syringe
or in the animal's body, the toxine is either destroyed or
simply neutralised, just as the acid in a given solution
may be neutralised by an alkali.

Yet there are several facts which negative this opinion,
or rather which tend to prove that this destruction and
neutralisation of the toxine, if destruction or neutralisa-
tion there be, is eftected through the agency of the cells
of the body. In the first place, if the whole were simply
a chemicaL process, we should expect it to take place
with mathematical precision. Thus, if -001 c.c. of horse's
serum did destroy or neutralise i c.c. of toxine, this
neutralisation should be apparent whether the mixture
be injected into a guinea pig, a rabbit, or a sparrow.
But it is not so ; on the contrary, it has been found that in
certain animals a very small amount of curative serum is
sufficient to render harmless a certain amount of toxine

NO.

VOL.

51]

when the same amount of serum utterly fails to do so in
animals of another species. Even if the same species of
animals be used the curative effect will differ in intensity,
according to whether the mixture be injected directly into
the blood, or into the subcutaneous tissue. .Moreover,
if a number of guinea-pigs be injected each with the same
amount of toxine and varying doses of curative serum, it
is of frequent occurrence that some animals will resist
when they have received but a very small quantity of
serum ; while others, which have received equal or even
larger quantities of serum, speedily perish. Had we to
deal with a simple chemical neutralisation or destruction
of poison, identical results should occur in all animals.
The action of the curative serum may also be inhibited
by weakening the cells of the animal body by the action
of bacterial or other protoplasmic poisons. Hence I
consider that the term "anti-toxic," which has been used
up to the present to denote this property of the serum, is
only approximately correct ; and I would prefer to sub-
stitute the word "curative," until such time as the mode
of action of the serum has been accurately determined.

Before speaking of the application of this method to
the cure of diphtheria in the human subject, and to the
results which have been obtained in the hands of such
experimenters as Behring, Koux, Khriich, Kossel,
Wassermann, Heubner and others, it must be pointed
out how the disease in man differs from and resembles
that produced experimentally in animals by the subcu-
taneous inoculation of the bacillus diphtheria', or of its
poisons. In both man and animals the symptoms are,
to some extent, produced (Roux, Behring, Sidney Martin)
by the absorption of the poisons secreted by this specific
bacillus. But in man the production of these poisons is
facilitated by the fact that the bacillus lives on the
surface of the membrane, where it is exposed continually
to the action of the air entering and leaving the lungs.
Now, it has been shown experimentally that the easiest
way of obtaining a large amount of diphtheria toxine
from the diphtheria-bacillus growing in an artificial
medium, is to expose the surface of this medium
to a current of air. In the respiratory passages of
man these conditions are exactly fulfilled, and the
bacillus is able to produce large quantities of toxine.
In the second place, the upper respiratory passages are
crowded with all sorts of non pathogenic and some
pathogenic micro-organisms, the chief among the latter
being the staphylococcus albus and aureus, and the
various kinds of streptococci. These multiply on the
soil prepared by the bacillus diphtheria-, and secrete
their toxine, which being absorbed, add their poisoning
action to the deleterious action of the specific bacillus.
In the preceding paragraph, I have drawn attention
to the fact that the toxines of another micro-organisn\
will inhibit the action of the curative serum ; and
there can be little doubt that the toxines secreted by
these micro-organisms in man will have the same effects.
The formation of the membrane also, and the mechanical
obstruction so produced, may in themselves be the cause
of death. It must be added, also, that diphtheria is
chielly a disease of the poor, and that in many cases the
diagnosis is delayed, and the treatment is not begun
until the patient is almost moribund. It is plain, there-
fore, that in the diphtheria of man we have al". the con-
ditions which are favourable to the production of the
poison, and the inhibition of the action of the therapeutic
serum. Hence we cannot be astonished that the ileath-
rate at the Hupital Trousseau in Paris amounted during
the last six months to 62 per cent, of all cases admiiteci
for this disease, and not treated with curative serum.

An examination of the statistics lately published by
Dr. Koux, the eminent director of the Instilut Pasteur,
will allow us to form some idea of the value of the cura-
tive serum when applied to man. The reason for
choosing these statistics is that they contain all the

i8

NATURE

[November i, 1894

elements necessary to enable us to form an accurate
opinion. The mortality among 3971 children admitted
during 1S90-1S94, and who were treated on ordinary
lines, i.e. without curative serum, amounted to 51 per
cent., the highest mortality being in 1S90, when it reached
59 per cent., and the lowest in 1S92, when it fell to 47
per cent. On February i, 1S94, Dr. Roux began the
inoculations. As soon as a child suffering from diphtheria
was admitted into the Hopital des Enfants Malades, it
received 20 c.c. of serum subcutaneosly, and if no im-
provement took place, 10 c.c. or more were again injected
next day. 448 children were thus treated from February
I to July 24, 1S94, and 109 died, the mortality being 24-5
per cent. At the Hupital Trousseau, on the other hand,
520 children were admitted during that period, and
treated without the injection of curative serum. Of these
316 died, giving a mortality of 60 per cent. This differ-
ence is striking enough ; but it is even more marked
when we come to analyse the results. In the first place,
we must eliminate from Dr. Kou.x's statistics 1 28 cases
which were shown by bacteriological examination not to
be diphtheria. This mistake is perfectly legitimate, as it
has been shown that without a bacteriological examina-
tion. It is impossible to make an accurate diagnosis.
The injection of the serum in a doubtful case is followed
by no harm, and as the result of the bacteriological
examination cannot be known for twenty-four hours, the
injection of the serum will, at any rate, prevent the child
catching the disease from his neighbour. The mortality
among such cases we know to be very slight, and in the
statistics of previous years, as well as in those of the
Hopital Trousseau, these cases are included among the
cures, so that the proportion of cures appears to be much
higher than it really is. These cases being excluded
from Dr. Roux's statistics, there remain 320 children in
which the bacteriological examination revealed the pre-
sence of the diphtheria-bacillus. Of these 20 died on
admission, before any therapeutic measures whatever
could be employed. Of the 300 other children 78 died,
giving a mortality of 26 per cent. We may further
divide these into uncomplicated cases, and those in
which tracheotomy had to be performed for laryngeal
obstruction. Of the uncomplicated cases, the mortality
in Dr. Roux's wards amounted to 12 per cent. ; whilst at
the Hopital Trousseau, where no serum was used, the
mortality during the same period reached 32 per cent.
In the preceding years it was 33 per cent, in the wards
in which Dr. Roux carried out his experiments.

Turning now to the cases in which tracheotony had to
be performed, we find that 49 per cent, of Dr. Roux's
cases died. At the HTipital Trousseau in the same
period 86 per cent, of the tracheotomised children
perished. Similar results have been obtained in Ger-
many, the mortality in some wards falling as low as 14
per cent. I'rof. Ehrlich has shown that the question of
time is a most important element, and that the chances
of obtaining a cure are infinitely greater when the
remedy is applied at an early stage of the disease. The
following table, reprinted Irom the Deutsche Medici-
nisclic W'ochenschriii. will explain this:

'I'ime eUpMd

(r-,m onKt of
di««aM 10 in-
jection of

Number of
caMi.

Number o(
euro.

Number of
deaths.

Cures,
per cent.

MTU in.

6

6

I

0

100

2

66

64

2

97

3

29

25

4

86

4

39

30

9

77

3

23

'3

.0

SOS

It will be noticed that the number of cures diminishes
according to the length of time which has elapsed since
the onset of the disease.

It appears to me to be difficult to explain away the
results obtained in France and Germany by simply say-
ing that the epidemic has been a mild one ; for in other
hospitals and institutions in which the curative serum
has not been used, the mortality has remained the same,
or even increased. In fact, it is plain that the serum
treatment of diphtheria is now established on a firm
basis, and that it is only right that we should at once
give the children in this country the benefit of the results
of experimental investigation which has been principally
carried on abroad. The British Institute of Preventive
Medicine is now taking steps to provide the serum at
cost price.

Finally, it is right to draw attention to the fact that
although the knowledge of the biology of the diphtheria
bacillus, and of the effects of its poison, has been based
on the investigations of ditferent observers — French,
German, and English — yet the discovery of the curative
efl'ect of the serum of immunised animals is the merit of
one man only — Prof. Behring, of Berlin.

M. A. RUFFER.

NOTES.
The Paris Academy of Moral and Political Sciences has
bestowed the Audiffret prize of iwelve thous.ind fiancs upon Di
Koux for his treatment of diphtheria.

.\ STATUE of Claude Bernard, the etninent physiologist, was
unveiled at Lyons on Sunday last, in the presence of a distin-
guished company.

The Nalicnal Zeitung states that news h.is reached Berlin
from the Kilima-Njaro district that the German bolanist, Dr.
Lent, and the zoologist. Dr. Krelzschmar, have been killed,
with several of their black followers.

Dalziel'S correspondent at New \otV says that a dispatch
received from Buenos Ayres gives particulars of a severe earth-
quake, attended by great loss of life, which occurred on Satur-
day, October 27, at the town of San Juan de la Fronteza, the
capital of the Province of Sm Juan, in the .Argentine Republic.
Many of the principal buildings are said to have been destroyed.
The shock extended to tlie towns of La Paz, Cordova, and
Rosario. The Xew York Hcrahl of Monday published a
telegram from Buenos Ayres stating that two thousand persons
have perished in the earthquake at La Kioja, and that twenty
thousand are homeless. This alarming report has not, however,
been confirmed.

NUMEROUS memoirs have already been based upon the rich
collection of Dutch birds brought together by the late Mr. J. P.
van Vickevoort Crommelin, of Harlem, and presented, after
his death, by his daughter to the Leydcn Museum. Ornitholo-
gists will therefore welcome the appearance of a complete
catalogue of the collection, which has been compiled by Dr.
Jenlink, the director of the museum, and forms the fourteenth
volume of the catalogues of the Museum d'histoire naturelle des
Pays-has. Nearly three hundred species are in all enumerated,
and the majority of these arc represented each by a considerable
number of specimens. A separate record is given of every
individual, notifying the sex and age, the place and date of
capture. An explanation which Dr. Jentink furnishes of the
exact locality of all the places mentioned should be of material
SCI vice to the student of the geographical distribution of these
birds.

NO. 1305. VOL. 51J

November i, 1894J

NA TURE

19

The London Mathematical Society, having been on October
23 duly registered as a corporation under Section 23 of the
Companies Act, 1S67, will hold its first general meeting at its
office, 22 Albemarle Street, on Thursday evening, November
8 next, at eight o'clock. The meeting is empowered by the
Articles of Association to elect a council and officers, to frame
bye-laws and to pass resolutions with regard to the affairs of
the Society. The following gentlemen have been recommended
by the present council (acting under Article Si for election
as th e new council and officers for the ensuing session : —
President, Major Macmahon, R.A., F.R.S. ; vice-presidents,
Messrs. M. J. M. Hill, F.R.S., A. B. Kempe, F.R.S.,and A.
E. H. Love, F.R.S. ; treasurer, Dr. J. Larmor, F.R.S. ; hon.
secretaries, Messrs. M. Jenkins and R. Tucker ; other members,
Messrs. A. B. Basset, F.R.S., and G. H. Bryan, Lieut. -Colonel
J. R. Campbell, Lieut. -Colonel A. J. C. Cunningham, R.E.,
Messrs. E. B. Elliott, F.R.S., J. W. L. Glaisher, F.R.S., A. G.
Greenhill, F.R.S., E. W. Hobson, F.R.S., and \V. H. H.
Hudson. At the close of the preceding business, an address
will be delivered by the retiring President (A. B. Kempe,
K.R. S.), on "Mathematics," after which the meeting will pro-
ceed to the ordinary business.

During this month, the following lectures will be delivered at
the Royal Victoria Hall, Waterloo Bridge Road, S.E. : — Novem-
ber 6, Prof. A. W. Rucker, F.R.S., on " The Electric Spark " ;
November 13, Mr. H. R. Mill, on "Unexplored England";
November 20, Miss Hope Rea, on " The Grand Canary and
its People" ; November 27, Miss F. Routledge, on "China."

It is proposed to hold a " Light and Heat Exhibition" at
Woodhouse Park next year. The park is situate at Shepherd's
Bush, and is, therefore, in direct communication with all parts
of London and the suburbs. The exhibits will be classified
into eight divisions, viz. : — Gas lighting ; electric lighting ;
various illuminants ; heating and cooking apparatus ; naval and
military; scientific apparatus ; photography; historical. The
promoters' intention is to hold a series of technical exhibitions
on the same site. Further information can be obtained of
the Hon. Secretary, Woodhouse, Shepherd's Bush, W.

Prof. W. M. Flinders Petrie will lecture on " Primitive
JigyP'i" ^t 'lis London Institution, on November 12. The
following are among the other lecturers and subjects for the
session ending March 4, 1S95 : — " Wonder- Working Plants,"
by Dr. David Morris, C.M.G. ; " Climbing in the Himalayas,"
by Mr. VV. Martin Conway ; " Extinct Monsters," by Rev. W.
N. Hutchinson; " The Newtonian Constant of Gravitation," by
Prof. C. V. Boys, F.R.S. ; "The Fauna of Rivers and Lakes,"
by Prof. Sydney Hickson ; " Twenty Thousand Feet above the
Sea," by Mr. Edward Whymper ; "The Netherlands," by Mr.
H J. Mackinder ; "Waves of Water and Waves of Light,"
by Mr. A. P. Laurie : " Nerves and Nerve Centres in Action,"
by Mr. Henry Power ; " Comets," by Sir Robert Ball, F.R.S. ;
"The Germination of Barley," by Mr. A. Gordon Salamon ;
" Electric Currents in the Body," by Prof. Victor Horsley,
F.R.S. ; "The Beautiful as seen in Minute Nature," by the
Rev. Dr. Dallinijer, F.R.S. ; "Theory and Practice of Pre-
ventative Inoculation," by Dr. E. E. Klein, F.R.S.

For the last week or so the weather in these islands has been
of a very unsettled character generally. Several areas of low
barometric pressure have reached us from the Atlantic, and were
accompanied by strong gales on nearly all our coasts, and in
the Channel very rough weather has been experienced, while
thunder and lightning have also occurred in many places. The
rainfall has been very heavy, especially in the west of Ireland
and south of England, where it amounted to nearly four and a
half inches during the week ending October 27, while in the

NO. 1305, VOL. 51]

Midland counties the fall reached about two inches. Since the
beginning of the year the rainfall has about reached, or exceeded,
the average in all districts except the Midland counties, where
the deficiency is three inches, and the west coast of Scotland,
where it is two and a half inches.

Prof. Cleveland Abbe include; the following among his
notes in the Monthly Wtather Revir.v for July :— On June 3 a
tornado passed north-eastward through the counties of Harney,
Grant, and Union, in Eastern Oregon. The most novel feature
attending the disturbance was the hail. It is stated that the
formation was more in the nature of sheets of ice than simple
hailstones. The sheets of ice averaged three to four inches
square, and from three-fourths of an inch to one and a half inches
in thickness. They had a smooth surface, and in falling gave
the impression of a vast field or sheet of ice suspended in the
atmosphere, and suddenly broken into fragments about the size
of the palm of the hand. During the progress of the tornado
at Long Creek a piano was taken up and carried about a
hundred yards.

Mr. a. Trevor-Battye, about whose safety some anxiety
has been felt, has reached Archangel from the island of Kol-
guef, where he had been studying bird-life. The proposed re-
lief expedition, for which subscriptions had been invited, is
consequently no longer necessary.

The German collector, J. Menges, describes, in the last num-
ber of Petermanns Mitleilungen, his travels in the Habr Auel
district of Somaliland, inland from Berbera. He visited the
country in 1S82, and gives a detailed account of his routes in
pursuit of big game.

The last Washington letter published by the American
Geographical Society states that the boundary line between the
United Slates and Mexico has been resutveyed, and a series of
monuments erected along it at intervals for a distance of 700
miles. The field operations for the survey of the Alaskan
frontier aie also completed, and the height of Mount Logan has
been confirmed as 19,500 feet, thus overtopping Mount St.
Elias by 1500 feet. Another interesting result of the joint ex-
ploration is to show that both these mountains lie within British
territory.

The Indian! Reservations of the United States in which the

aboriginal inhabitants are secure against aggressive civilisation,

j are fast diminishing in number and extent. The last number

I of the Bulletin of the American Geographical Society men-

I tions that four million acres of reserved land in the north-east

I of Utah, containing great mineral wealth, and hitherto the

home of the Uncompahgre and Uintah Indians, is about to be

opened to settlement, while nearly a million acres in South

Dakota are to be withdrawn from theexclusiveoccupancy of the

Indians of South Dakota, Oregon, and Idaho.

Consul C. S. Smith gives an account of the .\nglo-German
frontier survey in East Africa, in the November number of the
Geographical Journal. The survey, which was carried from
the mouth of the Umba River on the east coast to Kilimanjaro,
was effected in 1892, Mr. Smith being assisted by Mr. Imam
Sharif, the Indian surveyor, who subsequently accompanied .\Ir.
Bent to Arabia, and Lieut. G. E. Smith, R. E., and the German
party with uhcm they co-rperaled was under th- charge of Dr.
Peters. The route by the Umba Valley to Kilimanjaro was
found to be a practicable one, and the country traversed was,
as a rule, characterised by fertile soil ; but the land suffered
from the want of settled inhabitants, on account of the raids of
the Masai. Consul Smith suggests that immigrants from Indi.i
be encouraged to colonise parts of the Umba Valley ; and if
trade is ultimately attracted there, he points out that the seaport
of Wasin, although smaller than Mombasa, would be found
quite practicable for steameis.

20

NATURE

[November i, i8 o

The current number of Himmel khi/ ifn/^ contains a sum-
mary of a lecture by the Director of the Statistical Office of
Berlin, on the increase of damage by lightning, and on the effect
of lightning on the human body. The increase, which is unmis-
takable, is attributed to various causes, viz. the employn-.ent of
electricity in various industries, the continual change of the
form of the earth's surface by deforestation, drainajie, ^"iic, and
the impurities introduced into the atmosphere by the growing
consumption of coal. Prof, von Bezald has shown, some time
since, that for Bavaria the average yearly number of fires
caused by lightning amounted to 32 from 1S33-43. to 52 from
1S44-65, to 103 from 1866-79, »nd 'o '32 between 1 880 and
18S2. While in the year 1855, 134 persons were struck by
lightning, and 73 were killed, the numbers thirty years later
reached 1S9 and 161 respectively. It is noteworthy that persons
struck by lightning generally perceive neither lightning nor
thunder, but have the idea of being suddenly enveloped by fire.

To the facts of fishes out of water and of cr.ibs on dry land
we are accustomed, but the recent announcement of the dis-
covery of a flying Copepod is a novelty of which the naturalist
has probably never dreamed, though Giesbrecht's beautiful
figures of the Naples form; might well have induced the thought
of such a possibility. In the current number of the Zoolo^ischer
Anzeigcr (No. 459), Dr. Ostroumoff, of the Sebastopol
Biological Station, state; that he and his son were coasting
along the Khersonese peninsula on a calm clear morning last
July, when they noticed numbers of the tiny green Crustacean,
PonlcUina mcditerranca (Claus), flying just above the level of
the water. " Many of these Copepods were resting on the sur-
face-film, took springs into the air, where they described a long
curve, and fell down again upon the water surface." Dr.
Ostroumoff traces the origin of this very exceptional habit to a
peculiarity in the manner of exuviation that Poiitellina
probably shares with certain other pelagic Entomostraca, e.g.
Evadne, PUopts, which cast their skins at the surface of the
water " by the help of the air which becomes entangled in
{atihtilt) their rejected coverings." We should like to hear some-
thing more upon this interesting phenomenon, which involves
a complete change in the life conditions of the species. It is
difficult, at any rate, to imagine that so light and hairy a form
as Pontillina can return at will to the water again after once
breaking through the surface film.

The Bunsen flame spectra of the metals of the alkalies and
the alkaline earths have been studied by Herren J. M. Eder
and £. Valenta, by means of an apparatus which enabled
them to make exposures of extraordinary length. The
apparatus, described in a paper communicated to the Vienna
Academy, consisted essentially of a circular strip of platinum
gauze mounted in a slanting position on a nickel wheel. The
lower edge dipped into a solution of the salt to be examined,
and the upper edge passed through the Bunsen flame. The
wheel was kept slowly rotating by clockwork, and the steady
and uniform spectrum obtained was photographed. In the
case of sodium and potassium no lines were discovered that
were not already known from the spark and arc spectra,
although the ultra-violet sodium lines of wave-lengths 3303
and 3853 were well rendered. But with an exposure of some
thirty hours a large number of new bands appeared in the
violet and ultra-violet spectra of the metals of the alkaline
earths. They belonged chiefly to the oxides, and consisted
partly of double band.s arranged pretty regularly on a
continuous background. The spectrum of boracic acid,
obtained by burning a mixture of coal gas and 15(0,11,), in a
Linnemann burner, showed six new violet and ultra-violet
bands, which by their general character and their regular distribu-
tion correspond to those previously observed in the visible
spectrum.

NO. 1305, VOL. 51]

-V REMARKABLE instance of the anomalous behaviour of
bodies at very low temperatures is given by M. Raoul Pictet in
the Revue Scientifique. For the preparation of pure chloroform
by crystallisation at - 69° C. he used two copper refrigerators,
of capacities of 2i and 32 litres respectively. The former being
more convenient, it was used for the first series of experiments.
About 2 kgr. of commercial chloroform were put into a glass
test-tube, placed in the refrigerator, and surrounded by a tern -
perature of about - 120°, as indicated by a sulphuric ether
thermometer. The chloroform appeared turbid at —40" or
-50°, and was filtered and further cooled. At — 68°'5 the
cooling ceased, and very transparent crystals of chloroform
appeared on the walls of the test-tube. The chemically pure
chloroform thus obtained was used with great success in the
Berlin hospit.ils, and larger quantities had to be obtained. M.
Pictet noticed with great surprise that chloroform, refrigerated
in the larger vessel, was cooled to -81^ without a trace of
crystallisation. To test for experimental errors the small
refrigerator was exposed to the same cooling process, and the
chloroform crystals plunged into tVie larger one. But the
crystals dissolved at once, though the same thermometer,
successively plunged in the two refrigerators, fell from - 6S°'5
to -81°, where no crystallisation was going on. Finally, the
whole test-tube, with crystals at the walls, liquid chloroform
in the centre, and thermometer standing at -6S''S, was im-
mersed bodily in the liquid chloroform at -81°. The thermo-
meter gradually fell from -6S''5 to -St", while the crystals
dissolved before the observer's eyes. M. Pictet works out an
explanation of this striking phenomena on the basis of the theory
of radiation and his own theory of the molecular constitution
of solids and liquids, which leads him to the conclusion that
heat oscillations corresponding to low temperatures traverse
bad heat conductors with greater facility than they do compact
and heavy substances such as metals.

The fifth report upon the activity of the German Imperial
Physico- Technical Institute appears in the Ziitichiifl fiir
Instrtimentenkiinde. Besides the electrical work, which chiefly
dealt with resistances, the principal subjects of investigation
were connected with thermometers, manometers, barometers,
pyrometers, standard Hefner lamps and photometry, and the
physical properties of various kinds of glass. The branch
establishment at Ilmenau, in the Grand Duchy of Saxony,
has been extended by the addition of a technical school
for workers in glass instruments. Among the barometers
tested were the aneroids employed by Dr. von Drygalski
on his Greenland expedition. It appeared that low temperatures
are capableof creating a temporary disturbance in the indications
of these instruments. The chief optical work was connected
with |)hotometry. .\s regards the introduction of the Hefner
lamp as a standard of illumination, the report points out that
Germany is ahead of other countries in possessing a well-
authenticated standard of light which answers all itechnical
requirements. Recently the Institute has endeavoured to con-
struct simple and portable photometers for technical purposes.
Two such instruments have been constructed and found to
work well. The photometry of the arc lamps illuminating
" Unter den Linden " at Berlin, was also taken in hand by the
Institute. The examination of different glasses related mainly
to their solubility in water, which was found to give an indica-
tion of various other properties. The electrolytic precipitation
of zinc and other metals from dilute solutions was investigated
with a view to their preparation in a pure state. The examina-
tion of specimens of steel, of chronometer oils, and of coloured
thermometer liquids, was among the many tasks allotted to this
most useful and many-sided National Physical Laboratory.

Is the Pitt Press Mathematical Series there is no more useful
volume than "Arithmetic for Schools," by Mr. Charles Smith.

November i, 1894]

NATURE

21

The Cambridge University Press has published a second edition,
in two parts, of Mr. Smith's work. Evidently the book has
met with the reception it deserves.

The importance of experimental work is fully recognised in
the agricultural department of the Glasgow and West of Scot-
land Technical College. We have before us the reports on ex-
periments on the manuring of hay, oats, and turnips, conducted
in 1893 on the Home Farm of Cleghorn Estate, near Lanark,
and on about fifty other farms scattered all over the south-
western counties of Scotland. Prof. R. P. Wright, who
directed the experiments, must derive satisfaction from the
useful conclusions to which they have led.

The first part of Mr. J. W. Taylor's " Monograph of the
Land and Fresh-water Molluscs of the British Isles," published

by Messrs. Taylor Bros., Sovereign Street, Leeds, has just
appeared. It would be difficult to speak too highly of the fine
coloured plate which forms the frontispiece to the part, or of
the 138 well-drawn illustrations in the text. These figures will
be recognised by all conchologists as faithful representations of
the species they personify. The work is readable, concise, and
accurate, so far as it has been published, and the scientific
naturalist, as well as the systematic student, will find it useful

and interesting.

Mr. R. L. Jack, the Government Geologist of Queensland,
has issued his report of the progress of the geological survey for
last year. We learn from it that the most important work of
the year was the production of a geological map of the Ch arters
Towers gold field. The first edition of this map was issued
early in the present year, and Mr. Jack does not claim too much
when he says that no important centre of mining industry in
Australia his been so thoroughly mapped. The underground
work has now been completed, and it is expected that a second
edition, embodying this work, will shortly be published. With
Mr. Jack's report we received a report, by Mr. W. H. Rands,
on the Towalla and Marceba gold fields.

Within the past few years the number of students and
workers in glacial geology has greatly increased. The third
edition of Prof. James Geikie's " Great Ice Age," just published
by Mr. Edward Stanford, appeals therefore to a much larger
class than when the previous issue appeared seventeen years
ago. The work has been enlarged, and most of it has been
rewritten. The mass of glacial literature that has accumulated
during the last fifteen years or so, has rendered it possible for
the author to treat the glacial, and interglaclal, deposits of the
continent much more fully than in the second edition. The
phenomena of existing glacial action in Alpine and .Vrctic re-
gions, and the glaciation of Scotland, have been revised in the
light of recent work, and several rearrangements of matter
have been made. An important addition consists of two chapters
on the glacial phenomena of North America, by Prof. T. C.
Chamberlin. All glacialists will welcome this authoritative
account of the glacial accumulations of Canada and the United
States. It increases the value of what has always been a
valuable treatise.

The additions to the Zoological Society's Gardens during the
past week include a Barbary Ape (Macacu! iniius), a Turtle
Dove ('J'u)iur comiiiunii), four Barbary Turtle Doves (Turlur
risoritis], four Bubary Partridges {Caccabis pilrosa), a Crested
Lark {Alauc/a crislala) from Morocco, presented by Mr.
Alfred J. Gosling; a Caracal {Felis caracal), from South
Africa, presented by Mr. J. E. Matcham ; a Brown Capuchin
(Ccliiis faliicllia) from Guiana, presented by Mr. T. A.
Jenkins ; a Common Buzzard {Buleo vulgaris) from Aden,
presented by Captain R. Workman ; a Lanner Falcon {Falco
laiiariiis), captured at sea, presented by Mr. Arthur J. Elliott ;
a Ilawks-biUed Turtle [Clulone imbricala) from the East

NO. 1305, VOL. 51J

Indies, presented by Captain E. F. Tyacke ; two Long-nosed
Crocodiles (Crocodilus cataphractes) from West Africa, presented
by Mr. J. Banks Elliott, three Rusa Deer(C<rrr'«; hippelaphut,
(599) from Mauritius, presented by Rear-.\dmiral Kennedy ;
two Somili Ostriches {Slruthio molybdophanes) from Somaliland,
purchased ; four Plumed Ground Doves (Gcophaps pluinifera)
from Australia, received in exchange.

OUR ASTRONOMICAL COLUMN.

The Spectrum of 5 Cephei.— M. A. Belopokky has
taken a number of photographs of the spectrum of J Cephei —
a variable of short period — and determined from them the
velocity of the star in the line of sight. The results obtained
showed a periodic variation, and M. Belopolsky used them to
find the elemen's of the star's orbit, in the manner described
by Dr. Lehmann-Filhcs in the Astronomische NcKchrichUn,
No. 3242 (see Nature, August 2, p. 327). He finds that the
eccentricity of the orbit is 046 ; and the apparent semi-major
axis 180,000 geographical miles (207,000 English miles). The
period of the star is 5d. gh. The maximum velocity of ap-
proach is about 2 8 statute miles per second, and of recession
3'2 miles per second. The system, as a whole, is therefore
moving away from our own system. It is found that the light-
minimum occurs one day before the time of periastron passage
given by the computed elements of the orbi'.

The Rotation of Venus. — For eight years M. Flam-
marion has carried on observations of the polar caps of Venus,
and, in the current Comptei-rendus, he discusses the bearing
of his results upon the question of the planet's period of rota-
tion. It will be remembered that Schiaparelli concluded in 1890
that the rotation and revolution periods of Venus were of the
same length, viz. 225 days ; but later observations by Trou-
velot and others have led many astronomers to doubt this inter-
pretation, and 10 believe that the rotation period of the planet
is not very different from that of the earth. M. Flammarion
remarks that if it is conceded that the polar caps are really due
to snow or ice, their very existence is against Schiaparelli's view.
As the two caps are cfcen visible at the same time, it appears
that the axis of Venus is but slightly inclined to the orbit.
M. Flammarion's observations of markings on the planet are
not sufficient to determine the period of rotation, but they
appear to indicate that it is not far removed from twenty-four
hours.

The Lowe Observatory. — A few particulars with regard
to the new astronomical ohservaiory, which has lately been
erected in Southern California by Prof. T. S. C. Lowe, are given
in Saturday's Times. The observatory is seven miles by rail
north of Pasadena, and sixteen miles north-east of Los .-Vngeles.
Its altitude is about 3600 feet above the sea, and 2000 feet aoove
the hill at the base of the mountains, which are s'ery steep at
this point. While the crest of the range rises high above the
observatory and shelters it on the north, leaving, however, the
North Star visible, the entire southern horizon is unobstructed,
extending to the rim of a large segment of the Pacific Ocean,
about 100 miles distant, on the south and west. Astronomically,
it is nearly at the inierseciion of the 34ih parallel of north
latitude wiih the liSih meridian of liin.;itude west of Green-
wich. The new observatory is well equipped with the great
16-inch Clark leflector and other instruments which have done
notable work in the Warner Observatory at Rochester under
the directorship of Dr. Lewis Swift, who will now superintend
the Lov\e Observatory.

The Mean Parallax ok Stars. — In the Aslroiwmische
Nachrichlen, No. 325S, Prof. Hugo Gylden gives the results of
his attempts to discover a formula coniieciiiig the )urallax of a
star with its magnitude and its apparent motion. The fifty-six
stars which have had their parallaxes determined with a satis-
factory degree of accuracy were arranged in groups according to
their magnitude and according to their apparent motion.
Alter a lengthy series of tentative foruiuhc, the observed values
were connected within about ten per cent, by the following
formula,

P = o"-204 e -o-2'3'"> '*'"'

(m
-J "//( is the magnitude, and P the parallax
of stars exhibiting no proper motion. For stars with

22

XATURE

[November i, i8q4

proper motion a term /i' has to be added to P, the value
of which tends to o"'4S as the magnitude, and the proper
motion increases. So long ago as 1S72, Prof. Gylden
showed that it is justifiable to deduce the distance of a group of
stars from their apparent mean brightness in all cases « here the
probability of a certain inlensily of illuminating power is a
function of this intensity alone, without depending upon position
in space. And since the photometric law has been proved to
be at least approximately valid in this case, it may be concluded
that the brightnesses of stars reduced to the same distance are the
same, on an average, for all distances which can enter into our
consideration. But the most important result of the present
investigation is the determination of the mean parallax of first
magnitude stars reduced to the zero of apparent motion. The
value for this, which is o" 204, may he considered as identical
with Peters's value of o" '209, especially when it is borne in mind
that the latter value is not reduced to zero apparent motion.

THE INSTITUTION OF MECHANICAL
ENGINEERS.
C\^ Wednesday and Thursday evenings of last week, October
^-^ 34 and 25, a general meeting of the Institution of
Mechanical Engineers was held at 25 Great George Street ;
the President, Prof. Alexander B. \V. Kennedy, occupying the
chair. The two following papers were read and discussed :

" The Manufacture of Standard Screws for Machine-made
Watches," by Mr. Charles J. Hewitt, of Prescot.

"Drilling Machines for Cylindrical Boiler Shells," by Mr.
Samuel Dixon, of Manchester.

Mr. Hewitt's paper was of an interesting nature. He is the
works manager and chief mechanic of the Lancashire Watch
Factory, an establishment recently started at Prescot for the
manufacture of watches on a large scale in one works. The
factory system of watch production has been, as is well known,
carried to a very successful issue in the United States, where
the Elgin and Waltham Watch Companies annually make large
numbers of excellent lime-pieces wholly by machinery. .\s, m
all cases, where highly skilled hand labour, performing intricate
operations, is superseded by mechanical appliances, the ma-
chines used are of a h'ghly orgmised and costly nature. In the
case of the minute parts required in watch-making, this feature
is very strikingly emphasised. Perhaps some of our readers may
remember the exquisite little machine tools exhibited by the
Waltham Watch Company, at the Inventions Exhibition,
in the year 1SS5. These were a revelation to most English
watchmakers, accustomed to the small factories and per-
fectly rude appliances of the British industry, in which the
highest skill of the operators, due to special trainin; from
earliest youth, compensated tor the lack ol ingenuity displayed
in the construction of the tools used. In the case of
watches, as with so many other mechanical productions, the
brain capital expended in the employment of construction
of machines bears fruitful interest in the shape of less
skilled labour required in their use. The same thing may
be observed throughout the whole range of mechanical in-
dustry. The file, the hammer, and chisel are the primi-
tive tools of the engineer, requiring simple inventive power
in their inception, but great skill in their use. The planing
machine, by which the same end is obtained mecha-
nically, of producing a flat surface, as was got originally
by chipping and filing, required kno>vlcdge and skill for its pro-
duction, but a comparatively small amount of those qualities lor
its operation. The same thing is true, even to a greater extent,
in the case of the still more modern machine tool, the milling
machine, which is often attended by boys, possessing no
mechanical knowledge whatever, during its production of
finished lorms such as would have required a highly skilled
workman in former days.

The heaulilul machines referred to by the author in his paper,
examples of which »ere sho'ii at the niccungs, carry the
same principle many steps farther. As was remarked, the
machine shown for making wach-screws may lie said to stand
in the same relation to oidmary engineers' machine tools as
cosily gems to common building stones.

.Mr. Hewitt commenced his description by dwelling upon the
difficulties experienced by wal hiiiakcrs in old times, when
there was no general siandaid lor dimensions and pitch ol
screws, or lorm ol thread. Su h was necessarily the case with
hand-woik, but a machine can lie depended upon to turn out

NO. 1305, VOL. 51]

many thousands of parts exactly similar, so that a screw could
be put into a watch made years previously. The advantage,
naturally, is most apparent in the case of repairs and renewals.
Thestandardofscrewsadopled by the Lancashire Watch Company
at their Prescot Works, is that recommended by the committee
of the British .•Vssociation, and described in the report of 1S82.
It is a V.thread of 47); degrees, rounded top and bottom through
I'l of the height, and the pitch is directly related to the
diameter of the formula D = 6P' . In arranging the standard
the first business was to make master taps, which were pro-
duced on a small screw-cutting lathe specially designed for the
work, and having a corrected screw, accurate within very close
limits. Taps being thus produced, screw-dies were made to the
exact standard. When cut the thread requires hardening, and
this causes some amount of distortion, which is corrected by
grinding the threads with a soft steel lap charged with diamond
dust, the operation being performed in the same lathe that cuts
the thread. The die used is simply a tapped hole in the centre
of a small thin disc of steel, it being an object to have as little
metal as possible surrounding the hole, so as to reduce the dis-
tortion produced by hardening. Although the die is not split,
the pressure exerted by the die-holder is sulTicienl to produce a
slight modification in the diameter of the screw, and in this way
the alteration caused by hardening is corrected. During the
discussion this fact was questioned, but Mr. Hewitt says that
the statement is absolutely correct. The machine itself is of
an intricate design, as may be imagined when it is stated that
perfect screws are turned out automatically from the plain rod
or wire. There are four hollow spindles through which this
wire is fed forward to the operating tools, which are four in
number, and are carried on a revolving turret. There is also
a further tool for making the slit in the screw-heail for the
turn-screw. It would be useless to attempt to describe the
mechanism of this very ingenious lathe without the aid of
elaborate drawings. Indeed, during the discussion several
engineers, well skilled in mechanical appliances, confessed
themselves unable to follow the train of mechanism, even with
the aid of working drawings elisplayed on the walls of the
theatre. It is enough to say that the m.ichine will go on
without any attention so long as the wire to form the screw
lasts, when it slops of itself.

.■\. short discussion followed the reading of the paper, but no
fresh points were raised ; the speakers, for the most pari, con-
tenting themselves with complimenting the author on the
ingenuity of his tlesign.

On ihe second evening of the meeting, Mr. Dixon's paper, on
drilling machines lor boiler shells, was read and discussed. The
introJuclion of sieel as a material for steam-boiler construction
opened up a new era in that branch ol industry. When iron
plates only were used, a first-class b lilcr-shop possessed, as the
chief part of iis plant, simply a punching machine and a pair
of rolls for bending the plates ; the rest «.as done by handwork,
and that of a bignly skilled nature. Now that machinery has
superseded the handicraftsman, rivetling is done by most costly
and beautifully dc-igned hydiaulic apparatus, necessitating in
Us invcniioii a knowledge of applied science ol a nigh order.
Hanging ol the immense boiler-plates ol the present day is also
effected by heavy hydraulic presses. The rolls now used for
l)ending plaies have to be de^igned on true mechanical principles,
whilst great advance has been made in drilling inacfiincry. 'I'hus
tioifi ill the enormous boilers of our large steam hips and in the
iliniiiuitive mechanism ol watches, we see the skilled handi-
craltsmaii being displaced by automaiic macninery. It was
soon found impossible to make steel boilers with the same plant
that was used for the old type of iron boilers ; the
difference in the physical properties of the material
ahmc demanded a change in treatuiirnt. The soUer and less
homogeneous n on enabled the nvel-holes to be punched, but it
was found that this work done upon steel pbtes caused a
deterioration of the metal ; diilling, thereine, h.ad to be sub-
stliuied lor punching. Iron plates were punched in the Hat;
but It was lound that with steel when the holes were made in
th.it way, they often would not go together accurately so as to
take ihe rivets 10 ii.c greatest advantage, ihe lesuh being a weak
joint. '1 his did not mailer so much wlien steam pre>sures were
low, but Willi the greater demands male uy ihc marine
engineer in proilucing motive power ccunoinic dly, higher
prts.ures liad to be used, and there was no nia'gui lor loss in
ihc line of livening. It therefore became cusmmury to bend
the plates and put ihem in;o shape to form the shell ol the

November i, 1894]

NATURE

23

boiler before making the holes, which were then drilled in posi-
tion, and were necessarily true. This procedure involved the
use of special drilling machines, whilst economy demanded that
several drills should work at once in one machine so as to sive
time and be under the care of only one attendant. The chief
object of Mr. Dixon's paper was to describe the most recent of
these machines. The drill spindles are carried on supparts
which bring them to the work, and are adjustable to the varying
pitches and angles required. There is a cross-slide which can
be raised or lowered for carrying the drills for the circular seams,
and this is adjustable so as to suit the varying threads required.
There are five drills for this purpose, whilst six more are arranged
upon a vertical column upon the opposite side of the boiler
shell for operating upon the butt seams. One of the chief
difficulties in drilling holes in a built-up shell is the flexibility of
the work, which causes it to give way and buckle when the
pressure of the drills is brought upon it. So great has been
this drawback that it has been found more advisable in many
cases to use only one drill at a time, although there may
have been four spindles on the machine. Mr. Dixon has
overcome this objection in an ingenious manner by an
internal support which gives great rigidity to the shell, and
enables the larger number of drills to be brought into play at
once without their accumulated pressure causing deflection.
During the discussion an interesting point arose in connection
with this feature. It was said that twist drills which, when
properly ground, gave very clean holes and great accuracy of
work, could not be used on boiler shells, as they so frequently
broke in work. The author said this was perfectly true in
ordinary cases, but it was due to the springing of the shell
referred to. The statement is corroborated by the fact that
twist drills can be advantageously employed on work firmly
held on the drilling machine-table, whereas the older form of
flat drill would have to be used where rigidity could not be
obtained.

A NEW METHOD OF PREPARING PHOS-
PHORETTED HYDROGEN.
A NEW and extremely simple mode of preparing phos-
•^*- phoretled hydrogen is descibed iiy Prof. Relgers in the
current Zeitsclirift fiir Anorganischc Chemie. After reviewing
the usual mode of preparing the gas for demonstration purposes,
by heating yellow phosphorus in an aqueous solution of potassium
hydrate, and the other more rarely employed methods of pre-
paration— such as by the interaction of calcium phosphide and
hydrochloric acid, copper phosphide and potassium cyanide,
and phosphonium iodide and waiter — the question of the direct
combination of hydrogen and phosphorus is discussed. It
appears that the currently accepted idea that ordinary molecular
hydrogen does not comliine with phosphorus is founded upon
some old experiments of the French chemists Kourcroy and
Vauquelin, who state that when phosphorus is melted in
hydrogen gas, vapour of phosphorus becomes diffused in the
hydrogen, and confers upon it the power of ignition in contact
with oxygen without any combination between the phosphorus
and hydrogen occurring. In view of the great readiness which,
as Prof. Retgers has recently shown, warm hydrogen exhibits
to unite with free arsenic, it was considered possible that the
reason for the non-combination of hydrogen and melted phos-
phorus might be found in the low melting-point (44) of the
latter. Experiments were therefore made wiih red phosphorus,
which, of course, is capable of being raised to a much higtier
temperature. When dry hydrogen is led through a glass lube
containing red phosphorus, and afterward-; through a wash-
bottle containing water, pr.ictically pure hydrogen i< found to
escape. Immediately, however, a gas fla.ne is brought under
the part of the tube containing the phosphorus, combination
occurs, and the gas issuing from the wah bottle at once infl.imes
in the air. The non-spontaneously inflammable gaseous hydri le
of phosphorus is also therefore accompanied by a smaller
quantity of the spontaneously inflammable liquid hydride, and
a sufhcient qu.antity of the latter for demonstration may be
isolated by leading the vapours through a U-tube immersed in
a freezing mixture. Moreover, the solid hydride is likewise
produced as a yellow deposit near the he.ated p iriion of the
tube. Upon removing the flame from beneath the tube, the
bubbles of escap.ng gas cease to take fire as they emerge into
the air, and are found to consist of almost pure hydrogen. The
production of phosphoretted hydrogen is consequently entirely

NO. 1305. VOL. 51]

dependent upon the elevation of the temperature considerably
above the melting point of ordinary yellow phosphorus. The
new mode of preparation is recommended by Prof. Relgers as
being more convenient and elegant than the old-established
method of boiling phosphorus in caustic potash, as forming an
excellent example of the direct combination of two elements,
and as furnishing ample demonstration of all three hydrides of
phosphorus, the gaseous, liquid, and solid.

UNIVERSITY AND EDUCATIONAL
INTELLIGENCE.
Oxford. — The Rolleston Memorial Prize has been awarded
to M. S. Pembrey, of Christ Church, and E. S. Goodrich, of
Merton College, the papers sent in by these two candidates
having been judged to be equal. Mr. Pembrey was placed in
the first class in the Honour School of Natural Science in 18S9,
and is demonstrator in the Physiological Department. Mr.
Goodrich is still an undergraduate, and is assistant to the
Linacre Professor. At a meeting of the Junior Scientific Club,
held on Friday, October 26, Mr. W. J. Waterhouse, of Christ
I Church, exhibited some telephone cables, and Mr. W. P.
Pycraft exhibited some Natterjack toads. Papers were read
by Mr. W. Garstang, of Lincoln College, on some modifications
of the Tunicate pharynx induced by the violent ejection of
water, and by Mr. C. T. Blanshard, of Queen's College, on the
genesis of the elements.

Sir Henry W. Acland, K.C.B., has announced his resigna-
tion of the Regius Professor of Medicine, the resignation to
take effect at the end of the present year. Sir Henry is now
in his eightieth year, and has long been a leading figure in
scientific and medical matters in the University. His resigna-
tion will sever the link of many old associations. He has
consistently and bravely supported the cause of science in
Oxford, and that, too, at a time when scientific studies were
regarded in anything but a favourable light by the rest of the
University. It wa; largely due to his influence and energy that
the University Museum was built, and he has never failed to
support any movements for its further extension and for the
improvement of the teaching which is carried on there. One
of bis latest eflorts secured the building of the new Department
of Human Anatomy, and he has had the satisfaction of seeing
the medical school for which he worked so hard rise from
almost nothingness into considerable dimensions, with every
prospect of steady and healthy increase. He will carry with
him on his retirement the attection and good wishes of all
sections of the University.

SCIENTIFIC SERIALS
In the Ntiovo Giomale Bolanico Italiano for October, Sigg.
G. Del Guercio and E. Baroni describe the disease of Italian
vines caused by a Schizomycete, and known 3.'> ^ommosi bncillan
or pelivure. — Sig. C. Massalonga describes a large number of
abnormal growths in different plants. — .-Ml the other papers
concern the local Italian flora.

In the Journal of Botany for August, September, and
October, Mr. F. J. Hanbury adds seven more 10 the inter-
minable list of new species of Hieracium. — Rev. E. S. Marshall
describes and figures an apparently new species of CochUarui^
C. micai'ea, fiom Ben La*ers. — Messrs. J. G. and E. G. Baker
discuss the botany of an interesting corner of Westmoreland,
High-cup Nick. — The liricacce and the .\sclepiadea; of South
Alrica are treated of, respectively, by Mr. II. Bolus and Mr. R.

Schlechier. -tudenls of the local distribution of plants in

Great Britain will find other papers to interest them.

Sy/nofts^s Monthly Mcttoroloi^ical Magazim^ October. — Pro-
tection from litjhtning, by A. Mc.-Vdie. This is a summary of
one of the Circulars of Information issued by the Weather
Bureau, Washington. In adiition to a number uf rules for
erecting lightning rods, the pamphlet contains siaiis<ical tables
of injury to life ami property by lightning in the Uni<ed Slates.

I Full recognition is given by the author of the Report of the
Lightning Rod Conlercnce publi-hed in 18S2, and of the experi-

j ments made by Pmf. Oliver Lodge. — The recent drought in the

I Midlands, liy the Rev. (i. T. Ryves. During 26 days ending
September 21, only o'o6 inch of rain (ell at Tean Vicarage.

I Mr. Symons shows that at Barkby, Leicestershire, lio.inch of
rain fell. The same record shows that the first nine months of

24

NATURE

[NOVEMBEK I, 1S94

1S94 have been dry, but not nearly so dry as in some previous
years. — Enormous hailstones, by G. J. Symons. This con-
(MDS some cuttings from various papers of a severe thunder-
storm which occurred over a large part of the continent on
August 26 and 27 last. \\. Beaucourt hailstones are said to
have been picked up weighing nearly two pounds ; at many
place> they weighed seven ounces and upwards, and many birds
and some sheep were killed. — Climatological table for the
British Empire for the year 1S9;, by G. J. Symons. The
table contains data referring to iemper,iture, rainfall, &c., at
eighteen places. The highest temperature in the shade was ioS°
at Adelaide, on February 2, and the lowest - 48° at Winnipeg.
on February i. The highest temperature in the sun was 171
at Trinidad, which also had the greatest rainfall, viz. 92 5
inches ; the least fall was in London, I9'S inches.

SOCIETIES AND ACADEMIES.

r.\Ris.

Academy of Sciences, October 22. — M. Loewy in the
chair. — Experimental verifir.-ilions of the theory of weirs, with
liquid sheets submerged below or adherent, relative to the
delivery and the contraction in the lower part of the liquid
sheet, by M. J. Bjussinesq. — M. A. Trillat claims priority in
regard to processes of disinfection by formaldehyde. — ^On the
rotation poles of Venus, by M. C. Flammarion (see p. 21).
Variations of the level of water in a basin communicating with a
tidal port, by M. A. de Saint-Germain. A mathematical paper.
— Force acting at the suiface of separation of two dielectrics, by
M. H. Pellal. In the general case, the force is normal to the
surface of separation and in the sense that the specific inductive
capacity diminishes. Its value per unit of surface is given by
the formula

/■_ K,^)- cos 2a, K,$j- cos 2o«

8ir Sir

a, and a. being the angles between the normal and the direction
of the field, <f>, and <p„ the intensities of the field, on either side
of the surface of separation. — Experimental researches on the
freezing-point with different mixtures of alcohol and water, by
M. Kaoul Pictet. .\ table of the temperatures o( crystallisa-
tion of definite mixtures is given, and the results are plotted in
curves discussed in the paper. — A study of the combinations of
hydrogen fluoride with water, by M. R. Mettner. The author
has succeeded in obtaining only one hydrate possessing definite
properties. It has the composition HF.HjO and contains 523
per cent of I IF. 1 lie crystals of this composition melt at
- 35° <-^- ; they fume in the air, and have a specific gravity
greater than I IS- They are very soluble in the cold concen-
trated acid. — Researches on the mercuric sulphates, by M.
Raoul Varet. The thermal data for the normal sulphate and
for the basic salt HgSOj. 2HgO are given in detail. Where-
as sulphuric acid completely displaces IICN from its com-
bination with potassium liberating i- 25 4 Cal,, hydrocyanic
acid, even in dilute solution, replaces sulphuric acid in IlgSOj
with diseng.igement of • 235 Cal. Similarly hydrochloric
acid displaces sulphuric acid in llgsO,,. -Antimony vermilion
is not an oxysulphide, by M. 11. Baubigny. Analysis of the
colouring matter o( antimony vermilion, precipitated by sodium
thiosulphaie, shows that it is simply a lorm of SbnSj— Bismuth
nitrosalicyla es, by M. H. Causse. — Salivary glands of the
Apinw (/(/// mrllifica i and 9 ), by M. Bordas. On an un-
describcd caterpillar ravaging the leaves and fruits of the fig-
tree, in the arrondissemcnt of Puget-Thinicrs, by M. Decaux.
— On the mechanism of vegetable respiration, by M. L.
Maquenne. The author shows that the ratio of COj produced
10 O absorbed is sensibly altered by momentarily subjecting
leaves to a vacuum, and the respiration is at the .same time
rendered more active. The conclusion is given : The respiration
of plar' - --- to be the result of the slow combustion of
» very principle, which the living cell constantly

secrete. I'm the light, and which may accumulate when

there is ln^ulnclent oxygen in the surrounding atmosphere. -
The station of Schwcizersbild, by M. Niicsch.— Three geo-
logical sections in French Congo, by M Maurice Barral. —
l.atc geological researches in the Altai, by M. Venukoff. —
Kolalion movements observed in an aerostatic ascension, by M.
Vdnukoir.

NO, 1305, VOL. 51I

DIARY OF SOCIETIES.

London.

THURSDAY, NcvE.MBEK i.

Lnnban SoLiETV, at S. — Contributions to the Knowledge of Monocotyle*

donous Saprophytes; Percy Groom. — On an Error in the Descriptions of

Ihe EfTccl of a Centrifugal Force upon Growtli : Rev. G. Henslow. — On

Mediterranean .ind New Zealand Kctepora, and a Fenestrate Bryozoan :

A. W. Waters.
Chsmical SociBTV, at 8. — Tlie Elect romotive Force of Alloys in a Voltaic

Cell; .\ P. L.iuric. — The Action of Nitric 0.\ide on Sodium Ethylate;

G. W. Macdonald and Ormc Masson. — On Ethylic Butanetctracarboxyl-

ate ; Dr. B. Lean.

MOXDAV, NOVKMBER 5.

SociKTV OP Chemical Industry (Burlington House), at S — The Com-
position and Constitution of certain Alloys, by the late Dr. C. R. Alder
Wright, F.RS. ; Mr. Watson Smith.— Note on Oxidised Linseed Oil:
Mr. W. F. Reid.

Aristotelian Society (22 .Mbcmaric Street), at 8.— .'Vn Essential Dis-
tinction in Theories of lixpcrience ; Mr. Bernard Bosanquet.
TUESDAY, November 6.

Zoological Society, at 8.30. — Descriptions of New Species of (Eiio-
nvchis and .\llicd Genera of Coleoplcra ; Mr. Martin Jacoby. — On the
Hyoid Arch of Ceratodus ; Mr. W. G. Ridewood. — Third Kcport on Addi-
tions to the Batrachian Collection in the Natural History Museum : Mr.
G. A. Boulenger, K.R.S.

Royal Victoria Hall, at 8.— The Electric Spark; Prof. A. W. RQcker,
F R S

IVEDXESDAY, November 7.

Geological Society, at 8. — Notes on some Recent Sections in the Mal-
vern Hills: Prof. A. H. Green. F.R.S. — The Denbighshire Series of
South Denbighshire : Mr. Philip Lake. — On some Points in the Geology
of the Harlech Area : Rev. J. F. l>lake.

EntohologicalSocietv (ii Chandos Street, Cavendish Square), at 8.

THURSDAY, November 8.

Mathematical Society, at 8. — Mathematics, President's Address : A
Generalised Form of the Hypcrg<^ometric Series, and the Differential
Equation which is satisfied by the Series: F. H. Jackson. — Third (and
concluding) Memoir on certain Infinite Products: Prof, L, J. Rogers. —
On the Kinematics of Non-Euclidean Space : Prof. W. Burnside, F.R.S.

Institution o f Flkctrical Knginkbks, at 8. — Notes on Electric! ram-
ways (in the United States and Canada (Supplementary Paper): H. D.
Wilkinson. — Electric Traction, with Special Reference to the Installation
of Elevated Conductors : R. Sv. Blackwell and Philip Dawson.
FRIDAY, November 9.

Physical Society, at 5. — The Photographic Action of Stationary Liftht
Waves: J. Larmor, F.R.S. — On Vapour Pressure ; Prof. S. Youngs
F.R.S. — On the Luminescence of Glass : John Burke.

ROVAL ASTRONU.MICAL SociBTY, at 8.

SATURDAY^ November 10.
RovAL Botanic SociBTVt at 3.45.

CONTENTS, PAGE

Past and Present. l!y Right Hon. T. H. Huxley,

K.R.S I

Economic Products of India. Hy W. T. B . . 4

Chinese and Japanese Butterflies. By W. E. K. . . 6
Our Book Shelf:—

Collinson ; " Rainmaking and .Sunshine." — W. E. P. 7
Uo.skins : " The Elemenls of Graphic Statics : a Text-
Hook lor Suidenls of Engineeriiiij." — G 7

Eha ; "A Naturalist on the Prowl" 8

" A Son of the Marshes " : " From Spring to Fall " . 8

Cooke: " I. dible and Poisonous Mushrooms " . ... S
Letters to the Editor: —

What arc Ac(|uircd Characters? — Right Hon. Sir

Edw. Fry, F.R S ... 11

Discontinuous Motion. — A. B. Basset, F.R.S. ... 11

Capacity for Meat. — E, H. Griffiths 11

The .Swallowing of One .Snike by Another. — Baron

C. R. OstenSacken ... 12
On Recent Researches in the Infra-Red Spectrum.

(IlhiilralcJ.) liy Prof. S. P. Langley . . 12
The Treatment of Diphtheria by Anti-toxic Serum.

Hy Dr. M. A. Ruffer 16

Notes iS

Our Astronomical Column : —

The Spectrum of 5 Cephei 21

The Kolalion of Venus . . . . ■ 21

The l.owe observatory 21

The Mean Parallax of .Slars . 21

The Institution of Mechanical Engineers 22

A New Method of Preparing Phosphoretted

Hydrogen 23

University and Educational Intelligence 23

Scientific Serials 23

Societies and Academies 24.

Diary of Societies 24.

NA TURK

THURSDAY, NOVEMBER 8, 1S94.

ANCIENT METEOROLOGY.

Thecphrastus of Eresiis, on Winds and on IVeather
Signs. Translated, with an Introduction, and an
Appendix, by Jas. G. Wood, M.A., LL.B., F.G.S., and
edited by G. J. Symons, F.R.S. (London : Stanford,
1894.;

THIS book owes its appearance in an English dress
to the action of Mr. G. J. Symons, who believed
ts contents to be of such value and interest, that he
offered to defray the expenses of publication provided
I competent authority would prepare a translation of
;his neglected author. An able and willing translator
was found in Mr. J. G. Wood, sometime Fellow of
Emmanuel College, Cambridge, and we are thus put in
asy possession of the thoughts and the science of
Thenphrastus, or it may be the wisdom of Aristotle,
filtered through the mind of his favourite pupil. It need
scarcely be said that the book possesses a greater in-
terest for the archaeologist than for the pupil of modern
science, whose habit of thought is so different from that
of the old Greek author, that he will have a difficulty in
attempting to follow him.

A main object that Mr. Symons had in his generous
proposal was to offer the means for the study of the
gradual growth of our knowledge of meteorology, as
exhibited in the literature of past ages. He has, there-
fore, begun at the fountain-head, or as near as was pos-
sible or desirable. Mr. Wood seems to have been
animated by a somewhat similar ambition. He is afraid
, that in the study of meteorology, as at present existing,
the student may be tempted to forget " the far-off and
small but necessary beginnings which have conduced to
such an end." In this sentence there are several words
to which one might, if in a captious mood, take
exception. For instance, can meteorology, in any
sense, be said to have its beginning in the school
of Aristotle or Theophrastus ? Certainly not in the same
sense in which astronomy could be said to have its
rise in the work of Hipparchus or Ptolemy, for whatever
errors may have vitiated their reasoning and impaired
their results, they were in an advanced position com-
pared with those who taught or who studied meteorology
before they had an adequate conception of the existence
of an atmosphere. Again, is it necessary that science
should have its origin in error? Hasty generalisations,
imperfect judgment from insufficient facts, one must ex-
pect, but there will always be a central thought which
successive students will develop and render fruitful, and
in Theophrastus this germ seems to be absolutely want-
ing. It is rare, if not impossible, to find any paragraph
which is scientifically correct, or in which any train of
reasoning is sound, so that we fail to see how the efforts
of Theophrastus and his predecessor have in any way
conduced to the position, imperfect as it is, in which
meteorology now stands. Mr. Symons has told us that
he hoped to capture some new thought from the study of
this author. We venture to say he has been disappointed,
for whatever interest the book may have for the curious

NO 1306, VOL. 51]

and the literary student, it has little or none for the
scientific.

We have in this little book two treatises, or (as Mr.
Wood says we should now call them) "papers," of
Therophrastus, one on "The Winds," the other on
" Weather Signs." Both are marked by traces of haste
in their original compilation, and assume a better ac-
quaintance with the writings of Aristotle than most
people at the present day possess. But even with
this knowledge, the author is difficult enough to follow ;
accordingly Mr. Wood in his introduction has endeavoured
to give the English reader a notion of Aristotle's views
on Wind. This it will be admitted is no easy task, within
the small limits permitted to the translator ; and if the
explanation is not everywhere so clear nor so full as
could be wished', the fault lies not with Mr. Wood, but
in the intricacy of the subject, and in the difficulty the
reader finds in endeavouring to follow the subtleties of
Aristotle, and of accommodating modern thought and
knowledge to the ancient methods of expression. It is a
treat, after wandering through the mazes of "dry subli-
mation " and " moist sublimation," to come to Mr.
Wood's summing up of the whole matter, in which he
endeavours to concentrate his intimate knowledge of
this subject, as it presented itself to the Greek mind.
"The winds"— and Mr. Wood draws a necessary and
picturesque distinction between tti-oi;. di/f/iof, and
TTiKVjxa — " are separate and distinct entities, flowing
in definite courses, and not mere movements of
the same air hither and thither : that to produce wind
matter has to be formed, and the more matter the
greater the wind : and this matter is derived from the
earth, and is distinct from vapour."

With these misconceptions influencing the Greek
mind, and giving rise to infinite confusion, it would be
tedious to point out all the errors into which Theophrastus
fell. He was apparently not the kind of man to substitute
patient and exact observation for the assertion and teach-
ing of authority, or we might have had to hail him as
the founder of exact meteorology. One example will
suffice to illustrate his success as an original investigator.
We select the subject of annual or periodic winds
(fTijo-Kii), which Mr. Wood renders not very happily
by •' monsoons." The origin of these winds our author
teaches us is to be traced in the melting of the snow.
As the sun breaks up the frost, it sets the air in motion,
giving rise to the " monsoons," and inasmuch as the
thaw does not proceed with perfect regularity, so the
wind varies in constancy. At night, when the action of
the sun is less powerful and the thaw does not proceed,
the wind ceases to blow, but under e.xceptional circum-
stances the thaw may be so rapid that the wind is
perceived at night. Did none of his pupils seek to
verify these statements .'

The attempts at weather forecasting are naturally not
more happy than those dealing with meteorological
science, as now generally understood, but possibly quite
as accurate as many of the predictions -quoted in our
days, having for their object the determination of the
weather for a considerable period in advance. Certainly
they rest on a foundation quite as sound, and doubtless
assume an equal ignorance in_the public, that circulate
them from mouth to mouth, or it may be from nev\-spaper

C

26

NATURE

[November 8, 189 +

to news paper. " Whatever," says Theophrastus, " be
the condition of the air at the setting of the Pleiades,
such it continues for the most part, until the winter sol-
stice." This would cover practically nine months of the
year, if by the setting of the Pleiades is meant the setting
with the sun. The moon, too, is either the cause of a
change or the prognostication of it. " The change takes
place for the most part on the fourth day, and if not then
on the first quarter, aad if not then at the full." A
weather prophet of to-day would be discredited if he
hedged in this way. .^ clear crisp statement is now
necessar>' to secure credence, and attach disciples to the
school of the modem weather prophet. As one turns
over the pages that give the signs of fair or foul weather,
signs all more or less puerile, one is reminded of the
saying that Plato has preserved for us, "EXXi)«r (iei
iraidfV fffTf.

We can have no hesitation in asserting that the
appendix is the most valuable part of the book. Herein,
Mr. Wood has given an excellent account of the gradual
changes introduced in the nomenclature and in the sub-
division of the winds from the time of Homer and Hesiod,
through the Middle Ages, down to the present time.
Such an account is not only of great assistance to the
correct apprehension of old authors, but gives a great
deal of information on the introduction of fresh terms in
the description of the winds. Mr. Wood seems dis-
tressed as to the exact localisation of a wind that is
defined by reference to the azimuth of the sun, at rising
or setting at the summer and winter solstice. Of course
the azimuth varies with the latitude of the place of
observation, but .-Aristotle, writing for Greeks, described
positions as they were seen in Greece. Mr. Wood might
as well have taken into account the effect of refraction at
the horizon, or the alteration in the obliquity of the
ecliptic. In these days, we rarely attempt to determine
the direction of the wind within zd', and it is scarcely
likely that greater accuracy was attempted in Greece.
But whether Aristotle spoke of the equator or .Vthens,
the whole difference is only about 6^ so that the question
of accuracy hardly enters. We congratulate Mr. Wood
upon the amount of well-digested information he has
been able to give in this chapter. W. E. P.

TWO BOOKS ON AMERICAN ANTIQUITIES.

Travels amongst American Indians, their Ancient
Earthworks and Temples ; including a Journey in
Guatemala, Mexico, and Yucatan, and a visit to the
Ruins of Patinnmil, Ulatlan, Palenque, and Uxmal.
By Vice-Admiral Lindcsay Ijrine. (London : Sampson
Low, 1894.)

Journal of tlu Academy of Natural Sciences of Phila-
delphia. Second series, vol. x. part L (Philadelphia :
Academy of Natural .Sciences, 1894.)
\ U.MIRAL BKINE'.S pleasantly written book is the
■^ *• record of a journey made through the United
States, Guatemala, and Yucatan in the years 1869-70.
It is to be regretted lh.it his notes were not published at
once on his return home, as in those days Guatemala
and Yucatan were still almost unknown lands, and since
that date half a dozen books— few of them, it must be
HO. 1306, VOL. 51]

admitted, of great value — have made the country more
familiar to us.

The particular object of Admiral Brine's journey was
the examination of the earthworks and temples of the
American Indians, and the first portion of the book is
devoted to the red man and his works. Several months
were occupied in examining the mounds and earthworks
in Ohio.

On the difficult question of age, the author favours
the view that the circular and octagon enclosures are of
comparatively late date.

"But the figure which would have been absolutely
impracticable to construct without proper surveying
appliances for making accurate measurements, and fixing
the true angles, is that of the octagon. Even under the
most favourable circumstances, with the help of suitable
instruments, it would have required much skill and
calculation to trace a true octagon, whose embankments
contained within them an area exceeding forty acres.
It is difficult to suppose that an accurately designed
work of this shape and magnitude could have beeo
planned by Indians, or that the construction of a figure
so essentially scientific and unusual, could have been
originated by them. It is therefore possible to conclude
that the geometrical earthworks in Ohio may have been
raised by native tribes, acting under the direction
of European surveyors, or men who had received a
mathematical education."

Concerning the Indian tribes who actually did the
work of raising the embankments, the author adds in a
note that —

" Nothing has been found amongst the ornaments or
weapons that were placed in their burial mounds, which
supports the hypothesis that they w-ere different in race
or intelligence from the tribes that surround them."

From San Francisco, Admiral Brine sailed down the
Pacific Coast to Guatemala. He tells a story of Carrera,
th.it remarkable Indian of pure blood, who was for so
long the President of the Republic, and of whom mention
is often made in " Stephens' Incidents of Travel in
Central America."

" Colonel Garcia told us that Carrera always had on
his writing-table a toy representing Louis Philippe with
his hat in his hand. This toy had a rounded base, and
was so weighted that, when it was touched, it rolled
backwards and forwards, and would thus represent Louis
Philippe constantly bowing, hat in hand. Carrera when
engaged in official work would frequently make the toy
inove, and then would say to those who stood near him,
' It seems in that way, by too much bowing, that Louis
Philippe lost his throne. I shall take care that I do not
make the same mistake.' "

A journey in Guatemala in 1S70 was by no means as
free from risk as it is at the present day, " pronuncia-
mientos" and Indian risings were not of uncommon
occurrence, and .Admiral Brine was fortunate in escaping
any serious danger ; but he, no doubt, principally owed his
immunity from trouble to tact and good temper in his
dealmgs with the Indians. He was usually indebted to
the "padres" for hospitality on the road, and learnt
from the priests themselves how independent the Indians
had become in matters of religion.

'"The Indians come and go as they please,' said
Father Hernandez, ' light their own candles, hold their
own services before the altar, and frequently take one
of the saints out of the church, and carry it away to

November 8, 1894

NA 1 UKE

27

some hut, where for several days they will perform
nusical ceremonies before it, and then the saint will be
jrought back to its proper altar' — and again, ' they
:ome from afar to make offerings of blossoms and leaves,
ight candles before the altars of those saints they wish

0 honour, and then silently return to their huts.' "

There can b3 little doubt that in pre-Christian times
hey were accustomed to an elaborate ritual, and it was
)artly for this reai m that they took so readily to the
lereinonies of the Roman Church, but they never quite
bandoned their old beliefs. The twenty-four years that
lave elapsed since Admiral Brine's journey have not made
nuch difference in this respect ; and little rough altars
nay any day be found on the tops of abandoned temple
nounls with the scent of incense still hanging about
hem.

Admiral Brine camped for a few days in the ruined
emples at Palenque, and then travelled northwards to
Yucatan and visited the ruins of Uxmal. The last two
hapters give an interesting summary of the author's
otes and the conclusions to which he has come. With
hese conclusions it is not always possible to agree ; but
liat is not much to be wondered at, when dealing with a
ubject which is so closely enveloped in mystery as the
ivilisation and migrations of the races of America.

Happily we can feel assured that a distinct advance

1 our knowledge of the subject is being made, and that
lere is a fair prospect that, within the next few years,
ame at least of the mystery will be rolled away.

A good example of the very careful work which is being
one by numerous scientific societies in .America, in
ollecting and examining prehistoric lemains, can be
sen in Mr, Clarence B. Moore's account of his excava-
ons in the sand mounds of the St. John's River in
'lorida, and Mr. \V. H. Holmes's notes on the pottery
■om these mounds, which was submitted to him for
xamination, both published in the Joicrnal of the I
hiladelphia .Academy of Sciences.

The sand burial mounds occur frequently in the ■
eighbourhood of l.irge shell deposits. They are usually |
Lratined, the layers consisting of different coloured sand,
'ith sometimes a slight admixture of shell, and the human
ones and other objects are most frequently found in a
Iyer of sand of a pinkish colour, due to the presence of
Ortdered hematite.

It is not unusual to find in Indian burial mounds
ottery which has been purposely broken before burial,
s though in observance of some ceremonial rite, but
1 these sand mounds Mr. Moore found mortuary pottery
1 which the breakage or perforation had been made
efore the pottery was fired.

With some of the surface and intrusive burials were
ssociated iron and brass objects, showing them to have
een post-Columbian ; but nothing indicating contact
■ilh Europeans was found associated with the deeper
Uernients, and many of the mounds were entirely fiee
om evidence of contact with white men.

At Thursby Mound a number of very curious rough
ottery figures were found, representing squirrels,
irkeys, fish, turtles, &c , as well as some vegetal forms,
'hich are extremely rare in the norm.il art of the United
tales. The illustrations which accompany these notes
re numerous and excellent.

.MO. /306, VOL. 51]

As we hear that Mr. W. H. Holmes, whose admirable

work is so well known, is leaving the Bureau of
Ethnology at Washington, in order to take charge of the
new and liberally endowed museum at Chicago, which
is the outcome of the great World's Fair, we may look for
steady and increasing contributions to our knowledge of
the Indian races and their arts, which will not be limited
to the result of investigitions in the territory oftheUnited
States, but will include the whole .American continent.

The Peabody Institute of Massachusetts (principally
owing to the liberal support afforded it by Mr. C.
Bowditch, of Boston) has been able to set a good
example in commencing systematic work on the central
civilisations, by the investigations now being carried on
at the ruins of Copan, the site of which has been
acquired on lease from the Government of Hondur.ns
for a period of ten years. The Peabody Museum at
Cambridge, with its fine collections of pottery, origim.1
sculpture and casts, is fast becoming a centre for the
study of -American antiquities.

WA TTS' DICTIONAR Y OF CHEMISTR Y.
Watts' Dictionary of Chemistry. Revised and entirely

re-written. By M. M. Pattison Muir, M..A,, and H.

Forster Morley, M.A., D.Sc. Assisted by eminent

contributors, \'ol. I\'. With .Addenda. 8vo. Pp. 922.

(London and New York : Longmans, Green, and

Co., 1894.)
T^HE completion of the grand work before us renders
■'- it possible to form a fair estimate of its features
and its general character. No candid reader can fail to
appreciate the industry displayed by the editors and
contributors, in bringing together and sifting out the
vast mass of existing matter, in a science which is
experiencing so rapid a growth. Perhaps a greater
difficulty has been encountered in compressing within
reasonable limits the facts which must claim insertion.
This end has been reached by a style laudably laconic,
but at the same time free from obscurity, and by an
ingenious system of abbreviations, the editors — or we
might better say the authors, since the entire work has
been re-written — have confined themselves to the pure
science, leaving its thousand and one applications in
manufactures, metallurgy, and agriculture, to be dealt
with in the '• Dictionary of .Applied Chemistry," issued
by the same publishers. Without this limitation, the
cost of producing the work would have been simply
prohibitive.

Many of the articles included in this volume are, in
their value and extent, almost worthy to rank as inde-
pendent works. As instances we may mention the
section on the Proteids ; that on the Ptomaines — which
might have been a little more extensive — the article on
Phosphorus ; and, above all, that on the Physical .Methods
used in Chemistry. This article, which extends to 100
pages, treats separately of methods based on capillarity,
of crystallographic methods, of dialysis and diffusion, of
dynamical methods, of electrical methods, of procedures
based on the freezing-points of solutions, of optical
methods, of methods based on osmotic pressure, of
photographic method-;, of methods turning on the specific

28

NATURE

[November 8, 1S94

heats of solids, of thermal methods, of those based on
:he vapo'jr-pressures of solutions, of the viscosity of
liquids, and of methods based on volume-changes.

The chapter on electrical methods is supplied by Prof.
Dr. Ostwald, of the University of Leipzig. The author
gives an account of the rise of electro-chemistry and of
its development by Berzelius and Hisinger, and of its
dominance down to 1S40. It is remarked that, after his
first investigations, Berzelius did not undertake any ex-
perimental work on the action of electricity upon chemical
compounds, .-\fter 1S40 this theory- was found incapable
of e.xplaining facts which were being brought to light in
the region of organic chemistry, whilst its physical
foundations were shaken by the researches of Faraday.
More recently, Hittorf, Arrhenius, Helmholtz and others
have founded a new electro-chemical theory. Mention
is made of the discussion — not yet decided— as to the
origin of the current in the pile. The conception of ions
as the material conveyance of the current has been gradu-
ally introduced since the researches of Clausius, and is
taken into account in our views of decomposition. Not less
interesting is the account of optical methods. The first
part, from the pen of Mr. G. Gladstone, discusses refraction
and dispersion ; the second, on spectroscopic methods,
is contributed by Prof. W. N. Hartley, F.R.S ; and the
third part, on the rotation of the plane of polarisation of
light, is by Prof. Pattison Muir. In the part treating of
the spectroscopic methods we find studies of the infra-red
and ultra-violet absorption spectra, with notices of the
researches of V. Schumann, Waterhouse, Crookes and
Gladstone. In connection with the absorption spectra
— a subject by no me.ins fully explored — we have a
notice of Witt's views on the cause of colour in organic
compounds.

.•\mong the elements admitted or supposed, we find in
this volume, notices of phosphorus, platinum, potassium
rhodium, rubidium, ruthenium, samarium, scandium,
selenium, silicon, silver, sodium, strontium, sulphur, |
tantalum, tellurium, terbium, thallium, thorium, tin,
titanium, tungsten, uranium, vanadium, yttrium, ytter-
bium, zinc and zirconium, with compounds or derivatives.
The authors and contributors are noticeable for a
sobriety of statement ; they do not indulge in premature
conclusions and in speculations for which evidence is
lacking.

As regards the elements, the Mendelejeff classifica-
tion is adhered to, and in the accounts of their pre-
paration the recent results of Moissan have not been
overlooked.

The addenda comprise facts in mineral chemistry
which have been observed since the appearance of
Vols. 1., II., and III. and the printing off the final proofs
of the present volume. The addenda include nothing
on organic chemistry ; since to have noticed the recent
discoveries in that department would, in the opinion of
Mr. Pattison .Muir, have required the addition of many
hundred pages.

On comparing the present work with former diction-
aries of chemistry, whether in English or in any other
language, its superiority will appear beyond all ([uestion
It will be the obvious duty of all universities, colleges
&c., at once to add this new edition of " Watts " to their
libraries. ,

MO. I 30'3, VOL. 51I

DISEASES OF TREES.

Text-Book of the Diseases of Trees. By Prof. R.
Hartig, of Munich University. Translated by W.
Somerville, Professor of Agriculture and Forestry,
Durham College of Science, Newcastle. Revised
and edited by Prof. H. Marshall Ward, F.R.S.
2 (London and New York: Macmillan and Co.,

1S94.)
" T^ER Lehrbuch der Baumkrankheiten von R.
J-^ Hartig" has now appeared in English with all
the admirable illustrative plates of the second edition,
except the coloured plates at the end of the book, which
represent spruce and oak wood decomposing under the
influence of difi'erent fungi, and are therefore somewhat
exterior to the proposed scope of the work, " the diseases
of trees." The original, as Marshall Ward states in
the preface to the present version, owes its great charm
" to the simple method of exposition of the facts and
principles conveyed, as well as to the astounding rich-
ness of the information it contains. This is unquestion-
ably owing to Hartig's prominence as the leading inves-
tigator and authority on the fungoid diseases of forest
trees."

The great superiority of Hartig's work in this subject
has been acknowledged in France, by the publication
there, in 1S91, of a French translation by Profs. Gerschel
and Henry, of the Nancy Forest School, which was
entirely revised by the author.

Prof. Somerville, the translator of the jiresent English
edition, has followed a complete course of forestry at a
German forest school, and has been for some time
engaged in forestry instruction at Edinburgh and New-
castle. He has already written a valuable little book on
the structure of European timbers. The translation of
Hartig's book follows the original closely, and is smooth
and free from Germanisms.

The editor. Prof. H. Marshall Ward, whose qualifi-
cations for the work need no comment, has written an
excellent preface, besides revising the translation and
supplying short foot-notes in explanation of all scientific
terms, which might puzzle readers who have not studied
vegetable physiology very deeply, and in a few cases
giving his own opinion where he does not coincide with
the authors.

In the preface, the bold but thoroughly justifiable
statement is made that students of agricultural chemistry,
or of the physics and chemistry of soils, must thoroughly
master the facts of the structure and essential phenomena
of life by experimental investigation, and that the
chemistry of the soil taken alone is of less practical im-
portance. The fact is, that although the want of
sufficient suitable chemicals in a soil may render certain
tree-growth stunted and unproductive, yet the physical
nature of the soil, i.e. its degree of division and hygro-
scopicity, and the climate of the locality, are more im-
portant than the foiincr to ensure a healthy and vigorous
tree-growth ; whilst a good coating of decomposing dead
leaves will render a soil, which is chemically and
physically poor, capable of producing a fair crop of
timber. The influence of earthworms on soils has been
dealt with by Darwin, whilst that of bacteria and other
low organisms in decomposing organic debris to form

November 8, 1894J

NATURE

20

humus, and otherwise ass!Stin<j in the nutrition of plants,
has yet to be dealt with in a special treatise. Considering
the exhaustive and expensive investigations which are
carried out in the research of animal pathology, a large ex-
penditure by the State on the influence of bacteria
on soil and water would be justifiable, and would lead
to highly important improvements in agriculture and
gardening.

The editor meets possible objections from botanical
critics to Hartig's classification of fungi, by re-
marking that it is not fungi which are being studied
here, but their action on trees, and that students may
obtain a thorough knowledge of fungi elsewhere ; he
refers the forester who may be anxious to know the
remedies against disease to special works,' although
Hartig has given many practical hints as to treatment m
certain cases.

The book's great value lies in the way it teaches
students how to investigate disease, and a wide field is
still open to discovery in this respect.

The author's introduction chiefly deals with the causes
of disease and the procedure for investigating them ; and
it is reassuring to read that the transmission by inherit-
ance of disease is unknown in the vegetable kingdom,
and that we may use without hesitation the seed of plants
suffermg from any conceivable disease, and that with
them the law of inheritance is only involved in the case
of marked peculiarities, such as twisted fibre, dwarfed
habit, and other undesirable peculiarities. Superior
individual growth, however, is recognisable in the size
of the fruit, and large acorns produce vigorous oak
saplings.

As regards the distribution of matter in the work, the
first forty pages after the introduction deal with diseases
caused by plants other than fungi. Hartig states that he
has not noticed any appreciable damage done to forest
plants by Cuscutea or dodders, but Hess states that osier
willows are greatly damaged by Cuscuta Cronovii, Willd.,
an American species which has established itself in
Germany. The places where the haustoria, or sucker-
like roots of the parasite, pierce the cortex of the plants,
are rendered brittle, and the osiers so attacked become
useless for basket-making. The only remedy appears to
be to cut down the affected shoots in June and July, when
the dodder blossoms, and burn them. Bacteria which
cause such terrible diseases in animals rarely harm plants,
owing to the closed nature of their tissue elements as
compared with the anastomosing veins and lengthy
digestive apparatus of animals.

The main portion of the book — pages 40-224— deals
with damage done by fungi ; and alter a general description
of their mode of life, a very clear account is given of the
life-history of each destructive fungus, and of its effects
on its host. Fortunately, whilst several of these species
may destroy a few hundred trees here and there, the only
fungus which can be compared for its ravages on whole
woods with certain destructive forest insects is Pcziza
Wilikojiunii, which causes the widespread larch disease,
and has rendered the cultivation of larch almost im-
possible in certain districts in Great Britain and the north
of Germany, though it is said not yet to have occurred in

^ For instance, a translation of Hess» "Forest Protectioa " is tiow in
the press, and deals with these questions in detail.

NO. 1306, VOL. 5 l]

Ireland. The best preventive measure is to plant larch
only on suitable soils and in open airy situations, and to
mix it with other trees, and especially with beech.

Besides dealing with fungi which infest living trees,
there is a most interesting account of those which attack
timber, and thoroughly practical suggestions are given
for dealing with dry-rot caused by Mcrulius lacrimans.

Section ii. (pages 226-269) deals with wounds, and the
mode nature adopts for healing them, and also with the
dangers they aftbrd by the admission of the spores of
fungi to the interior of a tree. It is pointed out how
branches should be pruned or shortened so as to avoid, as
much as possible, the chances of future decay. Hartig
states that he has never known an instance of coal-tar,
when used for dressing wounds in trees, having proved
hurtful to them, although some foresters have asserted
the contrary.

Section iii. (pages 270-281) deals with diseases due to
certain conditions of soil, the chief predisposing factor
being the want of free circulation'of air in the soil, which
may cause root-rot in conifers, though, according to
Hartig, never in broad-leaved species. This latter state-
ment may rot, however, be quite correct, as Spanish
chestnut appears sometimes to suffer from root-rot, owing
to this cause.

Section iv. (pages 281-304) deals with diseases caused
by atmospheric influences, frost, insolation, want of
hght, hail, fire, coal-smoke, and lightning, and the book
terminates with a classified list of diseases arranged
according to the species of tree attacked, and the
respective organs which suffer.

\V. R. Fisher.

OUR BOOK SHELF.

Le Centre de VAfriquc. Autour du Tchad. Par P.
Brunache. (Paris ; Felix Alcan, 1S94.)

This record of travel in a previously unknown region
of north tropical Africa is published as volume 79 of
Bibliotlicqiie Scietitifique Internationale, although there
is nothing scientific about it, and the standpoint of the
author, so far from being international, is exclusively
and almost obtrusively French. The words " Autour du
Tchad," which are repeated as the running title of the
book, are entirely misleading, for the writer never came
into the vicinity of Lake Chad at all, but passed more
than 200 miles to the south of it. These are all the
adverse criticisms we have to offer. For the rest, the
book IS lively reading, and has the merits of brevity and
point. M. Brunache went out in 1891, as second in
command to M. Dybowski, in an expedition for the relief
of M. Paul Crampel, who had set out a year before, with
small resources, from French Congo, to try to reach Lake
Chad. Landing at Loango, the Dybowski expedition
went to Brazzaville, on the Congo, and thence up the
Mobangi and through a blank area of the map, peopled
by Dakoas and N'Gapus, across the watershed between
the Congo and Shari systems to neatly 8' N. The place
of Crampel's inurder was found, and a good deal of
punitive fighting was earned on with the IMohammcdan
negroes ; but here, at Crampel Peak, Dybowski found
that it was impossible to go farther, and the expedition
returned to the French outposts on the Mobangi. M.
Brunache is careful to show how much better qualified he
was for the command than the appointed leader, of
whose wishes he seems not to have been too considerate.
On his way to the coast our author met the expedition of

NATURE

[NOVEMBEK 8, 1894

M. Maislre, to which he transferred himself, and again
crossed the Congo-Shari watershed, made friends of
many of the native tribes, obtained treaties in the usual
way, and, pushing onwards, in spite of considerable hard-
ships, descended one ofthetributariesof the Shari, struck
westwards to the Benue, and so returned by the Niger.
The expeditions, which were two of the most important
of the last few years, did much valuable work in geography
and natural history ; indeed, M. Brunache insinuates that
Dybowski was too much devoted to collecting specimens
to make an ideal commander.

The book contains many interesting but unsystematic
notes on a number of tribes which were visited for the
first time by Europeans. E.\cept the Bonjios on the
lower .Mobangi.and the Mohammedanised natives of the
Sudan, they were all cannibals, eating their enemies
killed m battle, and occasionally their slaves. Amongst
all the tribes, women were well treated and consulted on
affairs of importance. The costume and habits of the
Saras, a particularly tall tribe, who inhabit the Shari
basin between S^and 9' N.,are described, we believe, for
the first time, and with such fulness and tact as only a
Frenchman can employ. In their country the surveys of
the expedition touched those of Xachtigal, who had pene-
trated so far southward across the Sahara, and thus com-
pleted the chain of modern European itineraries in West
Africa from the Mediterranean to the Cape of Good
Hope.

A number of reproductions of sketches exhibit types
of the natives encountered, and specimens of their art and
manufactures.

Helical Gears. By a Foreman Pattern Maker. (London :

Whittaker and Co., 1S93.)
This little book belongs to " The Specialists' Series " ; it
is entirely of a practical nature, and deals with a subject
little understood by engineers who do not happen to be
machme-tool makers. As there is probably no other
text-book on this subject, the work will fill a uselul
purpose. The author observes that a large proporfion
of so-called helical gears are incorrectly made, and are
therefore far worse than common gears. With this obser-
vaiion we certainly heartily agree. Cases are known
where an otherwise good machme has been spoiled by
the use of badly designed helical gearing.

The arrangement of the information is good. lUus-
traiiuns and diagrams are (reely used, so that what
would otherwise be difficult to understand becomes
clear and apparent. Patterns are clearly dealt with,
and their manufacture fully described. It is here
the hand of the practical man becomes evident. Many
hints are given, and instructions formulated, which
flavour btrongly of the " works." The author does not
pretend to deal with the purely theoretical side of his
subject, excepting in so far as the fundamental relation-
ships 01 the helical gears to the true screw or helix is
concerned. Beyond this the book is entirely of a practical
character, being eminently fitted to fulfil the require-
ments of the drawing-office and the works. N. J. L.

The Nests and Eggs of Xon-Initigenoiis British Birds.

By Charles Dixon. Pp. 360. (London : Chapman

and Hall, 1894.}
" Tm. present work," remarks Mr. Dixon in his preface,
" forms the companion volume to ' The Nests and Eggs
of British Birds,' and renders the subject of Briti>h
Oology complete, so far as our knowledge now extends.
It deals exclusively with the nidification of the birds
that do not breed in the British Archipelago, but visit
our islands regularly in winter, pass our coasts on
passage, or pay them their more or less irregular visits
as wandercis from their normal areas of disposal."
Nearly two hundred species are described as belonging
to this clas}. For each bird, information is given as to

NO ijo6, VOL, 51]

the breeding area, breeding habits, range of egg coloura-
tion and measurement, and the diagnostic characters of
the eggs. In an appendix, the author states his reasons
for believing that the nests and eggs of the following
species are at present unknown to science : — Rustic
bunting, Pallass grey shrike, Siberian ground thrush,
needle-tailed swift, solitary sandpiper, Siberian pectoral
sandpiper, curlew sandpiper, knot, Ross's gull, great
shearwater, collared petrel, capped petrel. Cape petrel,
and white-billed diver. A list of forty species, individuals
of which have been said to occur within the limits of the
British Isles, but which Mr. Dixon regards as doubtful
British species, is also appended to the volume. It
remains for the scientific naturalist to collect some de-
finite information on the species enumerated in these lists.

Commercial Geography. By E. C. K. Conner, M.A.

Pp. 200. (London : Macinillan and Co., 1S94.)
CoM.MERCl.\L geography, dealing as it does with the
facts that aftect manufactures, commerce, and agricul-
ture, ought to be widely studied in a nation having such
pronounced shopkeeping proclivities as the English. It
is right and proper that those who are to be the custo-
dians of our trade in future should know something about
the manner in which physical and political surroundings
alVect industry and commerce, and about the conditions
of success in the various industrial branches. Prof.
Conner treats these matters in a way likely to impress
students. His manual is divided into three pans, the
respective subjects of which are (i) commercial geography
and its principles ; (2' the geography of the chief pro-
ducts and others ; (3) countries, their agriculture, indus-
tries, and commerce. Trustworthy statistics are plenti-
fully distributed throughout the book, and they serve to
give an idea of the relative importance of different
countries as regards ditierent commodities, as well as
being useful for reference. Of course, no student would
be expected to commit these tabular statements to
memory. If the main facts contained in this volume are
grasped by students intended for commercial careers,
British commerce will undoubtedly be benefited.

Dynamometers and the Measurement of Power. By
John J. Flather, Professor of Mechanical Engineering,
Purdue University. (New York: John Wiley and Sons,
1892.)
A USEFUL practical treatise on this subject, in a con-
venient form for Technical Students, containing also the
mechanical theory required in the calculations.

The author has himself carried out a notable experi-
ment in the measurement of the power of a lull-siied
American locomotive, which was jacked up, and the
power taken olT by heavy supporting wheels ; a valuable
object-lesson for the pupils of his Experimental Labora-
tory of Purdue University. The long-continued measure-
ment of the power, coal and water consumption, iS:c., of a
large engine in full work — for instance of a steamer, the
.l/tVfor and others — is one of the most interesting and
instructive that can be provided for a class of enthusiatic
students of mechanical engineering. G.

Electric Light and Pou'cr. By Arthur F. Guy,
A.M.I.E.E. Pp. 346. (London : Biggs and Co., 1894.)
SiiME books, like the pedlar's razors, arc made to sell
rather than for use. Mr. Guy's volume is not one of
these. It has been issued " for the purpose of |)lacing
on record useful practical knowledge obtained by the
author during several years' experience of central-station
work, together with brief explanations of the laws which
govern the action of electrical apparatus in general use
for electric lighting." This brief description shows clearly
the ground covered. There are many similar works in
the market, but we do not know of one better suittd to
give the manipulator of electric dynamos an intelligent
knowledge of the forces with which he lias to deal.

November 8, 1894]

NA TURE

LETTERS TO THE EDITOR.

[The Editor does not hold himselj responsible for opinions ex-
pressed by his correspondents. Neither can he undertake
to return, or to correspond with the writers oj, rejected
manuscripts intended for this or any other part of Nature.
No notice is taken of anonymous communications.'^

Prof. Boltzmann and the Kinetic Theory of Gases.

In the discussion wtiich followed the communication of my
Report on Thermodynamics to the British Association at
Oxford this year, Prof. Boltzmann made some remarks which
appear to have been interpreted in a different light to what he
doubtless intended. In the absence of any shorthand writer's
verbatim report of the discussion, it is of course impossible
to recall his exact words, but I feel sure that Prof. Boltz-
mann will be much astonished to learn that his statements are
now widely circulated and quoted as being an authoritative
admission that the Kinetic Theory of Gases is nothing more
than a purely mathematical investigation, the results of which
are not in accord with physical phenomena ; in short, a mere
useless mathematical plaything.

Is it likely that such an able physicist would have de-
voted so many years to the development of the theory, and
would continue to work at it now if he regarded it in that light ?
Having had several conversations with him, both during and
after the British Association meeting, I gather that his views
are not nearly so pessimistic as the opponents of the kinetic
theory would wish to maintain.

The slalements were made in reply to a question as to how
far the ratios of the specific heats of gases as given by theory
accorded with the lesulls of e.xperinient. What I understood
Prof. Boltzmann to imply was that his investigations treated
the matter purely from a mathematical standpoint, but that the
values he obtained by regarding the molecules of a gas as rigid
bodies, viz. I '6 for smooth spheres, i'4 for smooth solids of
revolution, and I '3 for solids of any other form, accorded on
the whole rery fairly with the results of experiment. In that
respect the kinetic theory stands on exactly the same footing
as any other theory of mathematical physics. The evidence in
fa\our of the fundamental assumptions of any theory
necessarily rests on the agreement or want of agreement of
the deduction! with experience after due allowance is made
for the iact that the conditions imposed by the mathematical
difticuliies of the investigation necessarily differ from those
occurring in nature. I need only refer ro Prof. Boltzmann's
paper. " Ueber die Natur der Gasmolekiile" {Silziiitgsbciichte
dcr Wiener Akaacntie, Ixxiv. ii. 1876), for a more detailed
account of his views on the question of the specific heats.

The objection which has been regarded by some as most
antagonistic to the kinetic theory is that it does not afford an
expl.ination of the spectra of gases. But is this duty required
of it ? If the luminosity of gases were due to vibrations of
the atoms in the molecules, certainly there would be a difficulty
about regarding the molecules as rigid bodies ; but then such a
hypothesis would preclude a gas whose molecules were
monatomic from having any optical properties whatever. To
my mind, the electromagnetic theory of light entirely relieves
the kinetic theory from the burden which has been imposed
on it by its opponents, since it (for example) we regard the
molecules of a gas as perfectly conducting hard spheres,
spheroids, or other bodies moving about in a dielectric
"vacuum" {i.e. space devoid of ordinary matter), we shall be
able to account for the spectra by means of electromagnetic
oscillations determined by surface-harmonics of different orders
without interfering with the assumptions required for explain-
ing the specific heats of gases. There are, however, other
questions on which I should bi glad to see a continuation of
the brilliant discussion which had to be curtailed from want
of time at Oxford. G. II. Brvan.

Pelerhouse, Cambridge, October 23,

Instinctive Attitudes.

Mv attention has been called to Mr. M. M. Stanley's remarks
on instinctive altitudes in Nature of Oct. 18. I have been
for some years studying children's attitudes and expressions from
the eioluiion point of view ; and have from time to time taken
pholographi as opportunity presented itself. I have now a
considerable number which I hope to publish in that connection.

NO. 1306, VOL. 5 I J

One of the series accompanies this, and bears on Mr. Stanley's
remarks. It was taken in M.iy last, representing my youngest
child, then ten months old. She never crawled, but always pro.
gressed on all-fours ; and this photograph, taken instantaneously,
shows her mode of travel to and fro on the garden path. The
interesting thing about it is this : that the gait is front and
back legs on opposite sides, like a dog or a cat, not on the same
side, like a camel — a result which the evolutionist would have
predicted ; though of course we show a relic of the same habit
in walking, by swinging the arm on the opposite, and not on the
same, side as the leg. In this photograph, too, the heel and
toe action of the hind limbs is instructive.

One of my children, in addition to the ordinary crawl, used to
progress in a sort of three-legged fashion — it used the left hand

and the right foot for the forward step, rested itself on the
shank of the left leg tucked under its body, and this it used as
a foot to bring forward its body for the next step. Sometimes
this developed into a three-step mode of progression.

The bandaging, swaddling, carrying and wheeling about, which
the civilised infant has suffered for many generations, no doubt
partly accounts for the rarity of the quadrupedal mode of pro-
gression, by having hindered development of muscularity. The
quadrupedal mode of progression indicates greater strength than
the ordinary knee-crawl. S. S. BucKMAX.

Cheltenham, October 24.

James Parkinson, the Author of " Organic Remains
of a Former World."

Ln' a paper on the subject of museums, » hich was read in
1891 be/ore the meeting of an association, James Parkinson is
thus spoken of without any subsequent qualification of the state-
ment made : —

" Finally, a private lottery was arranged for its disposal (the
Leverian Museum), and in 17S5 the prize was drawn by James
Parkinson, a dentist, who took not the least interest in natural
history or in museums."

As the scientific world seems profoundly ignorant as to what
were the scientific qualifications and professional position of
James Parkinson, the following facts may be worth publishing
in Nature : —

James Parkinson, who resided at No. I Hoxton Square, was
not a dentist, but a surgeon. ■ In Johnston's Directory for 18 17
his address is thus given ; " Parkinson and Son, Surgeons,
No. I Hoxton Square." He had also an address in the Kings-
land Road. His death is thus recorded in the Gentleman s
Magazine of December 1824: " DeceUiber 21st, in Kingsland
Road, James Parkinson, surgeon, late of Hoxton Square."
There u\is a firm of dentists in London, whose address in John-
ston's Directory was as follows: — "Paikin-on and Kidman,
surgeon-dentists, i Racquet Court, Fleet Street " ; but they had
evidently no professional connection with James Parkinson.

The following list of works, &c., by James Parkinson, pub-
lished by H. I). Symonils, Paternoster Row, is giveii at the
end of a little book by him, of which the title is " Dangerous
Sports ; a Tale addressed to Children," printed for H. D.

NATURE

[November S, 1S94

SymjDds, Paterooster Row, iSoS. Their titles, which I briefly
gi»e, will amply prove his professional position : —

(1) " Medical Admonitions to Families." 5th edition.

(2) " Observation-; on the Excessive InJuIgenceof Children."

(3) "The Village Friend and Physician." 2nd edition.

(4) "The Way to Health."

15) "The Chemical Pocket-BoDk."
.(6) " Hints for the Improvement of Trusses."

(7) "The Hospital Pupil."

(8) "Observations on the Nature and Cure of Gout."

(9) "Remarks on Mr. Whitbread's Plan for the Education
of the Poor."

(10) "Organic Remains of a Former World." Volume the
First.

In additio.n to his "Organic Remains," Parkinson produced
'• Elements of Oryctology, an Introduction to the Study of
Fossil Organic Remains," which appeared in 1S22. .\ third
edition was published in 1S40.

Whatever may have been Parkinson's lack of interest in
natural history when he acquired the museum, he certainly
showed no deficiency in that respect when he produced his
" Organic Remains of a Former World," one of the most
valuable and interesting works of the kind that I know. For
farther information with regard to Parkinson, see the Introduc-
tion to Manlell's " Atlas of Fossil Remains," published by II.
G. Bohn in 1850, in which Parkinson's splendid plates are
reproduced. See also Allibone's " Dictionary of British and
American Authors " ; London, 1870.

SPE.NCER George Perceval.

Heobury, Bristol, October 29.

On Chinese Beliefs about the North.

From a review in Nature for the 27th ult. (p. 522) I have
been led to conclude that the " Theory of the Northern Origin
of the Chinese " enjoys the confidence of scienlihc men. .Should
this conclusion really be correct, the theory will give strong
support to the view which occurred to me while reading the
review.

By Sze-ma Kwang, a Chinese Prime Minister of great classic
knowledge (died 1086), the Rite of " Fuh " {i.e. bringing back),
anciently observed before changing the clothes of deceased
parents, is detailed as follows : — "Take a clean suit of clothes
prepared for the corpse up to the ridge of the roof; then
toviards till north call three times ' Pray, return ' ; then fold
up and being down the suit to clothe the corpse ; to detain t)u
j(7u/thus brought back, fasten the suit with silk (silken band) ;
bclore the burial offer to it viands and utensils with as much
reverence as is due to the parents alive " (l). In this ritual I
notice three primitive beliels unitedly preserved : firstly, that
the soul of the deceased could return if called, the belief current
among the Hos, the Bank's Islanders, and the Fijians of
modern times (2) ; secondly, that one could detain the soul
from departing by fastening a garment while addressing to the
deceased, as is meant by an old Japanese u-age on occasion of
meeting the passing soul, i.e., i^nis fatuus {t,). In the third
place, as is the case with the Kookies (4), this ritual indicates
the primitive Chinese belief in the existence of their other world
in the north.

The Eiily Chinese system of cosmogony, which is now
fragmentally but uniformly preserved in the books of two
antagonistic religions, viz. Confucianism and Taoism, has its
God uf the North named " Hiuen-.Ming," i.e. "Entering
Other World "(5).

Chan^ Hwa, a Piime Minister of encvclopa:dic erudition
(killed 303 A. D.), mentions in his work a Taoist belief in the
other wurld as extensive as 200,000 lis square, situated under-
ground in the north (6). Another Tauisi Kschatology, written
in the 9lh cenluiy a.Ij., relates that "the Emperor Vcn-tch,
who wa< ocated the ' Grand Imperial Master of the North,'
governt all spiritual beings" (7). .Mo.st probably connected
with theie beliefs is a folk-tale of the " ' South Dipper,' the
life-re.:islrar, and the ' -N'orth Dipper,' the dealh-regislrar " (8),
from whi^h is derived a popular romance of Chau Yen's bribery
to the latter star-god in order to have hi> destined longevity
increased from nineteen years to ninety-nine (9).

The Vo^.itcharya mystic< of Chin* define the north as " the
point wh:rea' ad the works are doomed to finish," and hence
"the point of enlerin,; Nirv.ana" (10). A dispute about
whether Chinese Buddhism in this case is entirely free from the
taint of Celeilial gloss, I am not qualified to decide.

Now let us return to Confucian literature. Confucius's own
opinion regarding the other world appears of quite agnostic
character, as is implied in his answer to Tze-lu (who inquired
about the slate of death) — " While you do not know life, what
can you know about death ? " (11^ ; as well as in his answer to
Tze-kung (whose question was about whether the deceased had
consciousness) — " If you die, you will know ; even then it will
not be too late to know " (12). But it is in those ancient sages'
tenets, which ihe great master preserved in his doctrine, that
the early Chinese belief in the northern spirit-land had been so
predominant, ihough tacitly implied, as to have caused an all-
reaching association of the North with everything related to
Death. So, early they styled the rooms containing ancestral
tablets the "North Temples" (13), and by the name " North
Hill" the graveyard has always been understood.

According to the " Tang-kung " (a portion of the Book oj
fiiles), Confucius was buried in the northern part of the capital
of Lu, and " the burial in the northern sides of towns
was the persistent custom of the three 'classic dynas-
ties,' i.e. Ilia, Ving, and Chau" (14). Forcibly this state-
ment reminds us of the Damaras, who place the corpse with
the face towards the north, to remind them whence they
originally came ; and also of the Vncas, who, expecting to go
to the east whence they came, turned the face of the corpse to
the east ; while the aboriginal Peruvians did not follow the
same usage (15). In fact, we find in Chinese records certain
abnormal examples, which indica'.e the stocks distinct from
original Chinese ; thus, two ciriises of different sexes discovered
from the mound of Prince Tsiikii, a Hiung-nii by descent, are
said to have had their he.ids turned eastw.ards (l6).

Mr. Herbert Spencer, after reasoning from materials exten-
sively collected, remarks: "Immigrant races have for their
other-worlds the abodes of their fathers, to which they journey
after death" (17); and unless they are an exception to this
general rule, the Chinese, whose old customs and traditions
have been shown to tend so much towards evincing their early
belief in the northern spirit-land, must have originally entered
their present domain from the North.

Also, in early Chinese speculations the north had been fixed
on as the store and source of the originating principle " Vin '
tor Negativity), and it has ever since been associated with
everything of " negative " characters — e.g. reposing, obscuring,
destroying, &c. Thus, in the symbolism of " Wu-h.ing ' (the
/■i:e Elements), v/Mex and winter are posted at the north (18);
of the nine divisions of the heavens the northern and the north-
western are named respectively " Dark Heaven "and " Dusky
Heaven" (19) ; of the five mountains worshiped by emperors
the northernmost one is called " Eternal Mountain " {Nan
Shan), because all beings are doomed to eternal repose in the
north (20>; and referring to the then admitted axiom — "the
north is the realm of slaughters and assaults" — Confucius once
reproved Tze-Iu for playing on a stringed instrument in the
" northern tones " (21).

.\s there should be nothing other than Death that might
combine in itself all conceivable characters of Negativity,
it would seem quite reasonable to trace the origin of these
associations of North and Negativity of Chinese speculations
into the old custom of burying in grounds lying towards the
north, which custom in its turn is easily traced to the early
Chinese entrance from the north.

Bibliography. — (1) ICiimazawa, "Sosai Benron,' Tokio,
1890, p. 4. (2) Spencer, " Principles of Sociology," 3rd edition,
vol. i. §83. (3) Terashim.a, " Wakan Sansai-dzue," 1713, tom.
Iviii. sub. " Hitotama." (4) Spencer, § II2. (5) Pan Kii, Peh-
hulling," 79 A.D. tom. ii. chap. i. (6) " Pcihwuh-chi,"
tom. i. chap. ii. (7) Twan Ching-shih, " Vii-y-ing Tsah-tsii,"
tom. ii. (8) Sie T>.aikang, " Wu Isah-tsii," circa 1610, tom.
i. (9) " Ven-i-S.in kwiih-chl," Kin's edition 1644, tom. xxxv.
pp. 4-5. (10) In-yii, " Maiidara Shisho, ' 1491, torn. i. (ll)
" Coniucian Analects," chap. xi. ; " Kncyclopxdia Britannica,"
9lh edition, vol. vi. p. 265. (12) Ving Chau, " Fung-nih-
liing," 2nd cent. A.D., tom. ix. chap. ix. (13) " Siun-tze,"
.■/><-ij 255 li.c. xxviii. (14) " I'ehhii-iiing," tom. iv. chap. x.
(16) Li Shih, " Suh Piih-wuh-chi, ' 13th
(17) Spencer, § 115. (18) " I'eh-hvi-
i. (19) "Liishi Cliiin-isiii," circa 239
(20) " Fung-siih-tiing," tom. x. chap. i.
.Shwohyuen," 1st cent. 11. c:. tom. xix.

KUMAGUSi; Ml.SAKATA.

15 Blithfield Street, Kensington, W., October 16.

(15) Sp.nccr, § 112.
lent. A.D. tom. viii.
liing,"tom. ii. chap.
U.c. lorn. xiii. chap. i.
(21) Liu Hiang,

NO. 1306, VOL. 51]

November 8, 1894]

NA TURE

The Planting of Timber Trees.

In Traill's sketch of the life of Shaftesbury (the first Earl),
the following pissage occurs in a letter from ttte Earl to the
steward of his estates in Dorsetshire ; —

" The best planting of timber trees is with nuts, acorns, seeds,
and footsets, and not with young trees removed . . . Insetting
of chesnuts, ac jrns, and seeds [it is desirable] to steep them
twenty-four hours in milk, which gives them a great advantage.
. . . If siccamotei [are planted] near my gardens, they will spoil
all my fruit with the llies they breed. Therefore pray pluck up
all the siccamores that are in the dry meadow behind my
kitchen-garden, an 1 in the room of every one of them plant a
che.snut, a walnut, or a honey-broke oak."

Can any of yoar readers inform me whether the soaking of
seeds in milk is now, or ever has been, ex'ensively practised, also
what is meant by a " honey-broke oak" ?

Alfred W. Be.\nett.

Rhynchodemus Terrestris in England.

The credit of the first discovery of this Land-planarian in
England lies not with Sir John Lubbock, as Dr. ScharfT stated,
but with the late Rev. L. Jfnyns (Blomefield), who, in his
"Observations in Natural History," 1S46 (p. 315), makes some
interesting remarks on the " Ground Fluke " [Fasciohi terrestris)
and its occurrence in the woods at Bottisham Hall, a locality
searched with success by .Mr. Harmer.

Rhynchodemus terrestris is widely distributed in England,
and I have found it in Derbyshire, North Lancashire, and
Westmoreland, under moist conditions and on a limestone
substratum.

.•\ny additions to the limited number of land-planarians in
Europe are of considerable interest, and mention may therefore be
madeof Prof. v. Graff's description {Bu'.l.Soc.Zool, France, xviii.
189J, pp. 122-3), of Rhynchodemus fyrenaiciis, n. sp., from
St. Jean de Luz, which is not alluded to by Dr. Scharff.

F. W. Gamki.e.

Oivens College, Manchester, October 26.

Tan-Spots over Dogs' Eyes.

The shepherds in some of the east counties of Scotland used
to call their bhck-and-tan collies four-eyed dogs, which agrees
so far with Mr. Peal's observations. These collies, twenty
years ago, were much in demand. Now they are hardly
allowed prizes at show-, and are becoming scarce ; black and
white, pure white, and, more commonly, brown dogs being
greater favourites. J. Shaw.

A CRITICISM OF THE ASTRONOMICAL
THEORY OF THE ICE AGE.

T N a communication to the British Association at
••■ Oxford, 1 gave an outline of a method of obtaining
a limit to the direct effect on terrestrial temperature of
the diminished winter sun-heat during epochs of great
eccentricity, the conclusion being that that effect had
been enormously exaggerated, and that the astronomical
theory of the Ice Age was really but a vague hypothesis,
having no sound physical foundation.

It will be remembered that Dr. Croll's theory is shortly
this : In the long northern winters in the time of great
eccentricity, far less sun heat is received than at present ;
the direct effect of this decrease in sun-heat is a pro-
portionate decrease in terrestrial temperatures, or, more
properly, a proportionate decrease in the excess of
terrestrial temperature over the temperature to which
the earth would fall in the absence ol all sun-heat. So
far Croll and Sir Robert Hall, the later expounder of the
theory, agree. Hut now they part company. Croll
affirms that the lowering of temperature thus calculated
would be quite insufficient, and that it is the indirect
effect of this fall of temperature (chiefly the effect in
disturbing oceanic circulation) which gives rise to the
additional lowering of temperature necessary for the
production of an Ice Age. liall, on the other hand,
affirms that the direct lowering of temperature due to

NO. 1306, VOL. 51]

diminished sun-heat is ainply sufficient to cause an Ice
Age. I use the word affirms advisedly, because neither
writer assigns any reason. Apparently Croll's reason
was that he thought he could see additional causes, which
if they existed must have contributed to the effect, and
also that previous writers had said that the direct ett'ect
of the change in sun-heat would not be sufficient ; while
Ball seems to have considered that he had strengthened
Croll's argument so much that the new form of the
theory was as strong without the ocean currents, as
Croll's was with ocean currents. It does not seem to
have occurred to either writer to ask what change in
temperature would be necessary in order to produce an
Ice Age, so that they might see if the cause they assigned
would be sufficient ; yet one would have thought this was
the first step towards formulating a theory.

The point in reference to which the two authors
employ numerical calculation is in obtaining the fall of
terrestrial temperature due to a reduction of sun-heat.
The problem is, of course, very complicated, and one
would expect that the most approved principles of physics
would be employed. Not at all. The physics is founded
on an incidental remark of the astronomer Herschel in
his " Outlines of .Astronomy" (edition of 1869), where he
assumes that the radiation of a body in space is propor-
tional to its absolute temperature. Yet it has for many
years been known to physicists that the radiation
increases faster than the temperature, and in iSSo or
iSSi what is now known as Stefan's law was published,
namely, that the radiation increases as the fourth power
of the absolute temperature. This would make an
enormous reduction in the calculated fall of tempera-
ture due to a diminished supply of heat — it 'uiouid reduce
it to o)ie-fotirtIi of the amount obtained on the erroneous
assumption employed by Croll and Ball alike. For if
temperature be solely due to sun-heat, the heat radiated,
say Afi\ where 6 is the absolute temperature, must be
equal to that received, say S, or

Ae* = S,
hence

d&_^ I e

rfS 4 s'

whereas the law of direct proportionality assumed by
Herschel, and adopted by Croll and Ball, gives

,/» _ 9
.I'S S'

a result four times as great as that obtained above —

Turning now to Croll's form of the argument, we find
one very remarkable inconsistency, which I think is no
bad illustration of the special pleading which character-
ises that ingenious writer. When, in the first place, he
desires to show how great may be the midwinter fall in
temperature due to diminished sun-heat, he thus employs
the argument I have criticised above : —

Let T,, be the present excess of midwinter temperature
at the latitude of the British Isles above the temperature
of space, i.e. above the temperature to which the earth
would fall if all sun-heat were to cease, and S,. the
quantity of sun-heat at present received on that
latitude on Midwinter Day, and let T^, and .S_,, be the
corresponding quantities for the supposed glacial winter.
Then, on Herschel's hypothesis, T,. is to T^, as S,. is

to S». Having

that way got an enormous fall of

temperature, Dr. Croll goes on to say that a vast pro-
portion of our midwinter temperature in these isles is
due, not to sun-heat received by us, but to heat carried
to us by ocean currents. These ocean currents, he
argues, will be diverted in the supposed glacial period,
and thus there will be a/«r//;crgreat fall in temperature.
The argument for this double diminution of temperature
is, of course, utterly invalid. If a great proportion of our
winter-heat be not due to sun-heat, then a considerable

34

NATURE

[November 8, 1894

loss of sun-heat would not alTect our winter temperature
very much, and the first argument is wrong ; if i: be all
due to sun-heat, then the first argument is right, and the
second wrong.

Nor do we find much greater accuracy in Sir R. Ball's
exposition of the theory. He is, indeed, much fairer than
Croll in taking the winter temperature as proportional to
the inrraij-t' daily supply of winter sun-heat, instead of the
Midwinter Day sun-heat, for it is evident that the adjust-
ment of temperature to sun-heat could not take place
instantaneously. But in another particular he seems
greatly to undirstale the case for the theory. His method
of calculating the average daily sun-heat is to take the
winter heat over the whole northern liemisfthere, and
divide it by the number of days in winter, and similarly
for the daily summer sun-heat. He applies the average
thus obtained to calculate variations in temperature in the
latitude of the British Islands. But when we remember
that the theory of the Ice Age is the theory of the tem-
perature of the latitudes from about 45^ N. to lat.
70^ X.,or, if you like, to the pole, it appears quite mislead-
ing to use numbers obtained from the sun-heat received
by the whole hemisphere. For the proportion which the
total winter sun-heat we leceive in these Isles bears to
the total summer-heat is expressed, not by Ball's numbers
37 and 63, but by the very ditVerent numbers 25 and 75.
The great disparity between these numbers, contrasted
with the temperate character of our climate, enables us to
see how futile it is to appeal to our imagination, as Ball
does, to conceive what vast ditTerences of climate must
be produced by differences in the daily receipt of sun-heat.

" If," he says, "a double supply of heat [63 measures]
be poured in like a torrent during the short season
[the 166 days of the short summer] while the single
supply [37 measures] is constrained to do duty over the
long season [the 199 days of the long winter], then an
intolerable climate is the result. The total quantity of
heat received on the hemisphere in the course of a year
is no doubt the same in each case, but its unsuitable
distribution bespeaks a climate of appalling severity — an
Ice Age, in fact."

How untrustworthy this style of argument is, will appear
when It is pointed out that in order to get a latitude m
which as large a proportion as 37 per cent, of the annual
sun-heat is receivtfd in the coldest 199 days, we have to go
as far south as Madrid, Naples, Constantinople, New
York, or Pekm I Yet «e are asked to believe that this
distributior, appioximately two measures in 166 day?, and
one in 199 days, will produce '"a climate of appalling
severity— an Ice Age, in fact." ("Cause of an Ice Age,"
P- 135)

There is another form in which the numerical method
is applied by Ball, the result of which, so far from sup-
porting the astronomical theory, would, if true, appear
to me to be conclusive against it. The present mean
annual range of temperature in Great Britain is about
20 F., and this, according to Ball, is caused by the dis-
parity in the daily receipt of winter and sumtner sun-
heat, acting agamst the mitigating causes. In the epoch
of k;reat eccentricity the disparity will be much greater,
and instead of the range of 20' F. we shall have a range
of 28' F. (•' Cause of an Ice Age," p. 151.) Ball then
goes on to say that such proportionate changes "are
quite large enough to imply profound differences in the
climatic condition. It is to be observed that, generally
speaking, the coldest places are those of the greatest
mean annual range. We are therefore entitled to infer
that the effect of such a change in the eccentricity as wc
have supposed, would be to increase the range, lower the
temperature of the hemisphere, and thus induce the
glacial period."

One would not consider such a statement out of place
in a popular series if it embodied the result of an inquirv
too complicated 10 be explained except in technical

NO. 1306, VOL. 51 j

language ; but that is not the case here, nor can the
conclusion be admitted as in the slightest degree probable.
In fact, so far from our being entitled to infer that such
an increase in the mean annual range would induce a.
glacial period, it appears to me that the mere fact that in
all continental climates north of Lat. 40", the present
range is greater than 28° F., entitles us to infer that such
a range would have no power whatever to induce an
Ice Age.

The problem of ascertaining the elTect of different
astronomical conditions upon terrestrial temperatures is
too complicated for accurate solution. How far the tem-
perature at any place depends on the sun-heat falling on
the outer layers of the atmosphere at the place (which is
all that we can lind by calculation), and how far on the
transference of heat by ocean or air currents, must always
remain to some degree uncertain, but that the latter
exert a preponderating influence seems evident for two
reasons — first, that while the sun-heat in each season
remains the same from year to year, the seasons them-
selves vary enormously (we have cold summers and
hot summers, warm wmters and cold winters, all with
unchanged conditions of sun-heal) ; aiul second, the
difference between summer and winter temperatures is,
in northern latitudes, but slight when compared with the
difference between the quantities of winter and summer
sun-heat received. Hence it appeared to me that no
modification of CroU's method of calculating differences
of temperature due to dilTeiences of sun-heat could be
relied on, for our knowledge of the transference of heat
from one region to another is too slight to enable us to
allow for its effect in our equations. But there is another
method which seems very reliable, especially when applied
to the British Isles, or any region where warm ocean
currents flow from the south. Not, indeed, that the
method enables us to calculate the loweiing, if any, of
temperature in the epoch of great eccentricity, but it
appears to enable us to fix, with soine degree of certainty,
a limit to the direct effect of the diminished winter sun-
heat.

The method depends on coinparing those regions
which now receive given allowances of summer and
winter sun-heat with the regions which, in the epoch of
great eccentricity, received the same allowances. If, fol-
lowing Croll, we suppose the temperature on Midwinter
Day to depend on the sun-heat received on that day, we
find that latitudes 90, 80', 70°, 61 , 52, and 43" no»v
receive the same sun-heat on Midwinter Day as latitude-*
90^, 80 , 70^, 60 , 50 , and 40 received on the Midwinter
Day of the most extreme eccentricity. In other words,
instead of Dr. Croll's fall of 45^ F. (I omit his decimal
point), the midwinter temperature of London would, in
the supposed glacial epoch, be lowered to that of Man-
chester at present, for Manchester is about r" north of
London. If, following Ball, we take the average daily
heat in winter as the basis of comparison, we should find
that lalitudesgo , Si ,71 -3,61 7, 52 4, and 43"-3 receive
in the present winter the same daily average of sun-heat
as latitudes 90", So , 70 , 60', 50 , and 40 received in the
long winters of greatest eccentricity. ( r, finally, if we
adopt the hypothesis, too favourable to the astronomical
theory, that the widwinier temperature depends on the
daily average through the 199 coldest days of the year,
we find that latitudes 84 5, 74% 63-5, 54', and 44°'2
ought now, so far as direct sun-heat is cimcerned, to
have the same midwinter temperature as 80', 70', 60', 50%
and 40 had in the supposed glacial epoch ; and when
it is observed that the summers in these latitudes were
then considerably hotierthan the summers in the former
latitudes, 84'-5, 74^63 5,54 , and 44 2 now aie, the utter
inadequacy of the astronomical theory to explain the
vast dilTeiences in temperature must surely be admitted
by any reasonable mind.

But when we take account of the ocean currents, it

November 8, 1894]

NA TURE

03

seems probable that instead of being lowered the winter
temperature in the British Isles would be raised in the
long winter of the supposed glacial epoch. For the Gulf
Stream flows at about four miles per day between the
Azores and Norway — that is, about ten degrees of the
earth's surface in six months, so that we may fairly
suppose the midwinter heating of these countries to be
dependent on the summer heating at about Lat. 40^-45'.
Now during the 166 days of the short summer in the
epoch of great eccentricity, these latitudes received a
greater daily average of heat than any latitude, even the
equator, now receives in an equal time. Hence it is
likely that the midwinter receipt of ocean heat in that
epoch was much greater than at present. This seems to
harmonise with the present condition of Mars. So far, in-
deed, as the evidence from ihe condition of Mars is admis-
sible, it seems to be quite inconsistent with Croll's view.

A paper dealing more fully with the mathemitical
portion of the subject will shortly appear in the Hhlloso-
pliical Mai;a:in€, and a more exhaustive criticism of
Croll's and Balls works will be found in the January
number of the Geological Magazine for 1S95.

It is satisfactory to know that although the astrono-
mical theory of the Ice Age has been steadily gainmg an
assured position among the semi-scientitic pub'ic — one
sees it referred to as the most generally accepted ex-
planation in such diverse works as Nansen's "Journey
across Greenland,'' and Laing's " Human Origins " — the
rising school of geologists are strongly opposed to it, as
contradicting the geological evidence.

Edw.\rd p. Culverwell.

NOTES.
The President and Council of the Royal Society have this
year awarded the medals as follows: — The Copley Medal to
Dr. Edward Frankland, for his eminent services to theoretical
and applied chemistry ; the Rumford Medal to Prof. James
Dewar, for his researches on the properties of matter at ex-
tremely low temperatures ; the Davy Medal to Prof. Cleve, of
Upsala, for his researches on the chemistry of the rare earths ;
and the Darwin Medal to Prof. Huxley, for his researches in
comparative anatomy, and especially for his intimate association
with Mr. Darwin in relation to the Origin of Species. The
Royal Medals have been awarded to Prof. J. J. Thomson in
recognidon of his contributions to mathematical and experi-
mental physics, especially to electrical theory ; and to Prof.
Victor Horsley for his important investigations relating to the
jjhysiology of the nervous system and of the thyroid gland, and
10 their applications to the treatment of disease. We learn as
we go to press that the Oueen ha? signified her approval of
these awards.

The following is a list of those who have been recommended
by the President and Council of the Royal Society, for election
into the Council for the year 1894-5, ^' 'he anniversary meeting
on November 30 : — President : Lord Kelvin. Treasurer : Sir
John Evans, K.C.B. Secretaries : Prof. Michael Foster, Lord
Rayleigh. Foreign Secretary : Sir Joseph Lister, Bart. Other
members of the Council : Dr. Andrew Ainslie Common,
William Crookes, Francis Darwin, Dr. Andrew Russell
Forsyth, Sir Douglas Gallon, K.C.B., Prof. Alexander Henry
Green, Sir John Kirk, K.C.B., Prof. Horace Lamb, Prof.
Edwin Ray Lankester, Prof. Alexander Macalister, Prof. John
Henry Poynling, Prof. Arthur Wdliam Rucker, Osbert Salvin,
Prof J. S. Burdon Sanderson, Dr. Thomas Edward Thorpe,
William Henry White, C.B.

We regret to note the death of Prof. M. Ducharlre, the
eminent French botanist. He was in his eighty fourth year.

NO. 1306, VOL. 51]

The Societe nationale d'HorticuIture de France is organising
an international exhibition of horticultural products and indus-
tries, to be held in May 1895.

The death is announced of Dr. Francesco Gasco, Professor
of Comparative Anatomy and Embryology in the University
of Rome.

Sir D. a. Lange, who was appointed in 1S58 the
constructor of the Suez Canal, has just died, and was
for some years director in England of that work. He was a
Fellow of the Royal Geographical Society, the Society of Anti-
quaries, and of other learned societies, and the author of
several important books connected with the Suez Canal.

A Blue-book has been issued containing Commissioner H.
H. Johnston's report of the first three years' administration of
the eastern portion of British Central Africa. The report deals
with the physical geography of the country, its meteorology,
agricultural conditions and resources, minerals, and fauna, with
the characteristics of the native races, and is altogether of con-
siderable scientific valui.

AFtER the great earthquake shocks in Greece, last spring, a
committee was appointed to make an examination of the
Parthenon, in order to ascertain what damage the temple had
sustained. The committee reported that the buildmg had been
seriously injured, and that there was great risk in allowing it to
remain in its present dangerous condition. They recommended,
therefore, that immediate steps be taken to strengthen it.
Renter's correspondent at Athens now reports that the Archaeo-
logical Society, at a meeting called to consider the question,
have voted an unlimited credit for the purpose of effec ing the
necessary repairs.

Mr. H. C. Russell, has sent us an account of the
travels of three bottle-papers used for determining ocean cur-
rents. One was thrown into the sea near the Crozet Islands in
March 1S93, and was found in September 1S94 between Cape
Banks and Cape Northumberland. The mean daily rate of this
appears to have been nearly eight miles. Two other papers
travelled over much the same course on the south coast of
Australia, at mean rates of six and nine miles a day. The
interesting point is that three current papers should pass over
more or less the same track, and agree sj well a; to the rate of
the current. The paper that made only six miles a day was
hampered with a heavy frame of wood, which had been put
round it as a protection when it should reach the coast.

The arrangements for the new session of the Society of .\rts
are now announced. The session commences on November 21
with an address from the Chairman of the Council, Major-
General Sir John Donnelly. The first regular paper will be by
-Mr. Hiram Maxim, on his " Experiments in .\eronactic5, " and
this will be followed the succeeding week by one by M. Hermite,
on "The Electrical Treatment of Sewage. " Two other papers
— one by Mr. Thomas Ward on "Salt," and one by Gen.
Michael on " Forestry " — will be read before Christmas. A
number of papers for meetings after Christmas are also an-
nounced. Six courses of Cantor Lectures are promised, of
which the first is by Prof. Vivian Lewes on " Explosives."
There will be, as usual, a course of Juvenile Lectures afier
Christmas ; the lecture this year is by Prof. C. V. Boys, F. R.S.,
hii subject being " Waves and Ripples. "

M. A. Delebecque, of Thonon, sends usi a small pamphlet
on the lakes of Dauphine. These lakes are veiy numerous,
many of them being mere tarns or lagoons, and some, although
figuring as sheets of water on the large-scale maps, are frequently
dry. He gives an a.:count of his soundings in the lakes of
Bourget, Aiguebelelte, Paladru, anl the smalUr lakes of the

36

NA rURE

[November 8, 1894

plateau and mountain region?. As to the'origin of these basin?,
M. Delebecque believts that [many of the smaller are due to
glacial action, either erosion or the iireguLir accumulation of
moraine stuff. He dots not confirm Forel's theory of the origin
of the lake of Bourget by the barring of a lateral valley by the
alluvium of the Rhone, but is inclined lather to look upon it ts
a result of movements in the crust. The origin of the other
lakes is more obscure, but some appear to be probably due to
movements of the strata, while others arose from the barring o'
lateral valleys by delriius. Particulars of temperature observa-
tions and analyses of the water of various lakes are given, ar.d
M. Delebecque concludes with an appeal to the local scientif c
societies of Dauphire to initiate systematic observations on the
lakes of the districi.

MONSIEUR KAVr, the celebrated French astronomer, who
lives in Paris, has lecent'y received a handsome token of
the admiration of his collejgues. All the members of the
Bureau des Longitudes, together with their president,

Mon.>i<.,ii ^e la Grye, assembled in his huu^c, and pre-
sented him with a silver enamelled tablet, on which Astro-
nomy and History are represented otTeiing a medallion to the
mo:t U5eful of caret rs. It bears ihe following inscription : "To
Hervc Faye, President of ihe IJureau lies Longitudes, 1874-
1893. The homage of his colleagues." The two allegorical
figures arc sitting in the clouds, and Astronomy is pointing
to the comet which wa< discovered by the illustrious astronomer.
This interview greatly affected Monsieur Faye, who had only
retired on account of the ne* law, opposing the perpetuity of
the presidency.

Mk. J. Theodore Bent and Mrs. Bent leave London
to-morrow, November 9, for an exploring journey in .\rahia.
They go fir»t to Karachi, and thence by steamer to Muskat on
the Gulf of < 'man, where the land journey commences. It is

NO. r -?o5. VOL. 5 I ]

Mr. Bent's intention to cross -■Vrabii from east to west, and, in
doing so, to revisit the Hadramut Valley, and continue his
archaeological researches there.

Mr. Trevor-Battye, to whose arrival at .\rchangel we
referred last week, has telegraphed to the Times a detailed
account of his experiences on his visit to Kolguef Island. He
landed on the north-west coast of the island on June 21, at the
mouth of the liver Gosina, accompanied by Thomas Hyland
^a bird-skinner) and a spaniel. .\ few days later they started
to cross the isl.ind, and found the journey very difficult on
account of the bogs and snow-tilled ravines, and the severity of
the weather, which was either cold and foggy or intensely hot,
calling out swarms of mosquitoes. Birds were abundant, but
the only mammal seen was a fox. At length, after a week's
travelling, a party of Samoyedes and many reindeer were found
near Chum. Mr. Trevor-Battye made this his headquarters
until August 20, gaining much information as to the language
and customs of his hosts, and assisting ihem in their hunting.
He records the capture of 300 Brant geese in one net, and
on another occasion the slaughtering of 300 reindeer. A
Russian trader arrived who had visited the island for thirty-
five successive years, and he remained a month transacting
business with the Samoyedes. On September 18 Mr. Trevor-
Battye sailed with the Russians for the mainland, and ex-
perienced bad weather on the way, and much difficulty in
navigating the shallow water near shore. His orthodox com-
panions attributed this difficulty to the presence of a Samoyede
idol which was very displeasing to St. Nicholas ; but Mr.
Batlye clung to his trophy, though at some personal risk.
After landing, there was a four days' journey in sledges to
Oksina, and a three days' boat trip up the Pechora to Ust
Tsilma. It was the worst time of the year for travelling, as
the land was marshy, and the rivers, unnavigable on account of
floating ice, were not yet frozen over. However, Mr. Trevor-
Battye and his companion struggled on in sledges or carts, and,
after adventures with wolves and all manner of delays, ulti-
inalely reached Archangel in excellent health. Kolguef
I.-land appeared to be of alluvial formation with no trace of
massive rock, being possibly a remnant of thi.- delta of a great
river. The coast-line is quite different from that shown on the
chart. Ext ensive zoological and botanical collections were
secured.

At the annual meeting of the Royal Cornwall Geological
Society, held at Penzance, on November 2, Mr. Howard Fox,
the President, reviewed the progress made during the pa-t
twelve months towards the elucidation of the many unsolved
problems of Cornish rocks. Mr. F. J. Stephens had found
radiolarian cherts in the Meneage conglomerate, and on the
mainland near .MuUion. Mr. Ussher, of the Geological Survey,
had traced Upper Devonian straia in the St. Germans district,
west of the Tamar. The President himself had found similar
strata west of Padstow, and a peculiar rock at Dinas Head in the
same districi, which contained nearly ten per cent, of soda. In
Its compact form it might easily be mistaken for a chert, but it
passed into a nodular variety showing spherulitic structure.
Whether it were a soda felsite (keratophyre) or a sedimentary
rock altered by contact metamorphosis, such as the Adinole of
Ihe Hartz, was a question on which pclrologists weie nut as yet
in absolute agreement. The evidence from sedimentary rocks
in contact with greenstone on Cataclens and Round-hole Points
indicated a sedimentary origin, as did General McMahon's
notes on the sections he had e^amined. Crinuidal remains bad
been found in black shales of the Ordovician district of Veryan,
interbeddcd with radiolarian cherLs, but these shales had as
yet yielded no typical zonal fauna. He (Mr. Fox) had sent
some sections of the carboniferous cherts of East Cornwall

November 8, 1S94J

NATURE

to Dr. Hinde, who found those from Carzantic Quarry, near
Launceston, full of radiolarian casts, withoneinstanceof structure.
Further investigations were being made in this diiection by Mr.
Ussher and himself. In conclusion, he drew attention to the
unwise practice of taking away shingle from beaches faster than
it was being reproduced by nature.

In connection with the controversy over preformation and
epigenesis which at present agitates the biological world, we
may draw the attention of our readers to a series of articles
contributed by Wilhelm Haacke to the Nalnnvissenschaflliche
Wochenschrift ['&A. i.\. Nos. 32-3S, Aug. and Sept. 1894), under
the title " Schopfung und Wesen der Organismenform." The
writer passes under review the various theories of the origin and
development of organisms which are associated with the names
of Albrecht von Haller, Wolff, Blumenbach, Goethe, Lamarck,
St. Hilaire, D.irwin, Weismann, Roux and other biologists, and
criticises them from a standpoint not far removed from that of
Oscar Hertwig. The synthetic views of the author do not give
one the impression of finality, but, as a historical rhumd of the
oscillations and tendencies of thought upon some fundamental
problems in biology. Dr. Haacke's essay is distinctly interesting.

The importance, both from economic and from scientific
points of view, of a thorough knowledge of the floating
fauna and flora round our coasts is so generally recognised,
that our readers will be interested in a recent article which,
in concise form, furnishes a number of valuable data upon
this subject, and must considerably facilitate the further
prosecution of similar researches. The article forms part of a
report contiibuled by Mr. \V. Garstang to the current number
of the JourtHil of the Marine Biological Associatioti, in which
the author gives a record of his observations upon the fauna
during 1S93-94, and upon the breeding seasons of marine
animals at Plymouth, and also submits an attempt to construct
a calendar of the changes observable in the floating fauna from
month to mojith in the same locality. Dcr Aiifang ist das
Sc/nver, and marine biologists familiar with the seeming fickle-
ness of marine phenomena know well the powers of discrimina-
tion and the experience necessary for the production of
accurately generalised information under this head. It is most
satisfactory, therefore, that the valuable work upon our north-
eastern fauna, which Prof. M'Into;h has conducted for many
years past at St. Andrews, should be now supplemented I'y
the obiervations of another competent naturalist on our south-
western shores. If, as we hope, arrangements can before long
be made for carrying on continuous observations at the young,
but promising, station at Port Erin, and on the west coasts of
Ireland and Scotland, we shall in good time be equipped wiih
data of the most valuable kind for determining many problems
connected with the natural history of our migratory and other
fishes.

The second of the Tufis College StuJies embodies the
results of an investigation of the development of the lungs
of Spiders {AgeU-iia invia and Theiidium tepidaiiorum) by
Orville L. Simmons. The author's interpretations difl'er ei.^
tirely from those of Jaworowski, already noticed in our columns
(October 25, p. 621). He finds that the lungs arise as ir.-
foldings of the posterior surface of the appendages of the
second abdominal somite, the lung cavity being essentially a
pit in the body-wall at the base of, and behind, the appemlages
m question. The development of the lamellx agrees strikingly
with Kingsley's observations on the origin of the gills of Liiiiiilus,
and lends considerable support to Prof. Lankester's well-known
theory. The trachea; develop behind the next pair of limbs at
the apex of a similar depression of the body-wall. In their
earlier stages these appendages show on their posterior surfaces
certain feeble undulations, which the author regards as aborted
M^- I .;c6, X'OI.. 5 I I

lung- or giU-lamellx. The tracheal twigs arise as simple in-
growths comparable, in the author's opinion, with the infoldings
which produce the lamellx". Mr. Simmons concludes that the
lung-book condition is primitive, the tracheae of Arachnids
being derived from it. How far he is right in this conclusion,
and how far (if at all) Jaworowski has gone wrong, are
questions that we hope will not long remain undecided.

A REDETERMINATION' of the temperature of greatest density
of water has recently been carried out by M. de Coppet, who
gives an account of his results in the AniiaUs de Chiniic el de
Physique. On account of the very slow change of density
about that temperature it is difBcult to determine it within a
hundredth of a degree Centigrade. The method adopted was a
modification of that of Despretz. A number of thermometers
were mounted in the lid of a cylindrical water vessel with their
bulbs at various distances from the bottom, and symmetrically
disposed about the axis. On immersing the vessel in a cold
water bath, a current was set up, passing down along the sides
and ascending in the centre. After a while the current stopped,
and then was reversed. The course of the current could be
followed by the readings of the thermometers. The water
having the greatest density would sink to the bottom, and the
temperature of the lowest bulb would be approximately that of
greatest density. But the temperature at which the lowest
thermometer stopped for a time was higher on cooling than on
heating. The curves exhibiting the two series of changes are,
however, symmetrical, and give the temperature of maximum
density as 3° '982 by the hydrogen thermometer under a pressure
of one atmosphere.

A SIMPLE method of obtaining light of different wave-lengths
for use in polarimetric work is described by Landolt in the
Silziingiberichte of the Berlin Academy, No. 3S. White light
from an Auer's glow-lamp is passed through different absorp-
tion cells containing coloured solutions which can be readily
procured. Details are given of the preparation of five such
cells, by means of which red, yellow, green, light blue, and
dark blue light may be obtained. Examined spectroscopically,
the light is in each case found to consist of a band, and is not
by any means monochromatic ; if, however, the rotation be
less than 20°, or, with one or two of the cells, even if it be
considerably greater, the field of the polarimeler remains
apparently uniform in tint. The wave-lengths with which the
bands may be taken to correspond, were determined by using
the cells in a set of observations on the rotation of quartz, and
comparing the results with those obtained for the rotation of
quartz by Broch's method. The wave-lengths were thus ascer-
tained to be not far removed from those of the Fraunhofer lines
C, D, E, F, G. The instrument employed was a Laurent
half-shadow polarimeter fitted with a Lippich's polariser. -A
simple method of this kind has long been required for the
speedy investigation of rotatory dispersion. It is also of im-
portance to have a ready means of obtaining light of short wave-
length, which is of especial service when determining the rota-
tory power of feebly active substances.

In a paper communicated to L'Elediicien (Paris), M. G.
Darriens gives an account of some recent experiments he has
made on the chemical reactions which take place in the
ordinary lead accumulator. To get an idea of the chemical
state of the negative plate of an accumulator, the author treated
a given weight of the negative plate of a fully-charged accumu-
lator with hydrochloric acid, and measured the volume of
hydrogen evolved. He then measured the volume of hydrogen
evolved when an equal weight of ordinary sheet-lead was dis-
solved in hydrochloric acid, and obtained practically the same
number as before. This experiment seemed to indicate tl.at
the negative plate of a charged accumulator consists of metal'ic

NATURE

[November 8, 1894

lead, in a very finely-divided state, and that a charged acoumu-
lator simply represents an ordinary voltaic cell in which lead is
the negative element. In order to test this point, the author
has examined the behaviour of several forms of primary battery
in which finely-divided lead is useJ as the negative metal. In
the case of a Daniell cell consisting of a copper plate in a
saturated solution of c >pper sulphate and a plate of spongy lead
in dilute sulphuric acid, the liquids being separated by an
ordinary porous pot, the mean of several experiments gave the
value 064 volt as the electromotive force. A calculation
of the electromotive force of this cell, based on the heats
of formation of the different substances, gives 03 volt,
so that it would appear as if lead in this very finely-divided
state evolved more heat when it entered into combination than
under ordinary conditions. If this supposition is true, it is
necessary to add o'34 to the figures calculated for ordinary sheet-
lead, to allow for this "allotropic" modification of the metal.
If we apply this correction 10 the observed electromotive force
(I '6 volts) of an element consisting of PbO. and pure lead, we
get the quantity I '94 volts, which represents the electromotive
force of the element PbO. and spongy lead. The above values
can be utilised to calculate the quantity of heat necessary to
convert ordinary lead into spongy lead, the value obtained
''^'''S 7 '4 calories. With a Daniell cell, as described a'love, in
which the spongy lead had a surface of one square decimetre,
and weighed 440 grms., the mean electromotive force was 057
volts and the capacity 1375 ampere-hours, the internal resist-
ance being about 01 2 ohms. This form of cell is subject to
the same objection as the ordinary form of Daniell, namely, that
after a time the copper-sulphate solution diffuses through the
porous pot, and the copper is deposited on the negative metal.

The filtration of water on a large as well as on a small scale
has acquired quite a different significance since the bacteriology
of water ha; sprung into existence ; and it is as a u.seful, because
impartial cjntribution to this subject, that we welcome Surgeon-
Major Johnston's short treatise on "the relative efficiency of
certain filters for removing microorganisms from water." The
iavesligatiuns here rec )rded were made as qualifying work for
the degree of I). Sc. at Edinburgh University, and the experi-
ments were carried out in the Public Health Laboratory of the
University. The fillers examined were those known as the
.\tkios patent water filter, Maignen's table '• Filtre Rapide,"
the Nordmeyer-I3erkefeId filter, and the Pasteur-Chamberland
filter. The first two filter-; are described as useless for sterilising
water, both of them not only allowing " micro- organisms to pass
through the pores," but affording " a suitable nidus for the
growth and multiplication of micro-organisms, which are found
in much greater numbers in the filtered water than in the un-
filtered." The " lierkefeld " and "Chambcrland " fillers were
more elaborately examined. The "Chamberland " cylinder
selected was one intended for slow filtration, and in comparing
the results obtained with it and the " IJerkefild" cylin ler re-
spectively, it must be borne in mind that the rate of filiation
through the latter was 5 J times greater than through the former,
although after Iwenly-four hours' continuoui filtration, the rate
was only 1 1 limes greater. Major Johnston's opinion, based
on his examination of these particular cylinders, is that "the
Pasteur-Chambcilan<l filter is the best and only one on which
reliance can be placed for perminenlly sterilising water." An
important pjint, and one which has been overlooked by the
author, is the temperature of the room in which the filters were
kept whilit under examination, i'rcudenrcich found that a
higher or lower temperature had a marked effect on the effi-
ciency of the Chambctlnnd filter. It is to be regretted that in a
thesis of this kind, purporting to have a bibliography, the aulhor
should have entirely neglected to mention or refer to, in any

NO. I3OD, VOL. 51]

way, a large number of important investigations on these par-
ticular filters published during the last few years in various
foreign journals.

Mr. G. J. Sy.mons has contributed to part ii. of the Report
of the Chicago Meteorological Congress, an interesting summary
of early English meteorological literature, embracing the years
'337~'699- He only deals with some fifty books and pamphlets
contained in his own library, bat his special knowledge of
meteorological bibliography enables him to give some useful
particulars about these old works. We can only briefly refer
to a fi;w of ihem here. In the Bodleian Library at Oxford
there is (as far as is known) the earliest continuous weather
record in the world, containing observations by the Rev. W.
Merle from January 1337 to January 1344. A few copies of a
translation of this work were printed in 1891. These observa-
tions show that the weather at that lime was very similar to
what it is now. In 1670, "The Shepheard's Legacy" was
printed. This work is excessively scarce, and is the earliest
edition of what has since been reprinted many times as "The
.Shepherd of Banbury's Rules for judging the weather." In
1671 appeared "A discourse concerning the Origine and Pro-
perties of Wind," &c. This treatise is noteworthy as being pro-
bably the first in which the theories of the winds are compared
with details of the trade winds, monsoons, &o. In 1696 a work
entitled "New Observations on the Natural History of the
World of Matter," &c., by the Rev. T. Robinson, was published.
It gives the earliest description yet known of the strong local
wind known in Cumberland as the helm wind. The sub/ect of
this wind has been brought before the Royal Meteorological
Society on several recent occasions, and that Society appointed
a committee to collect information upon it.

THt; November number of the Journal of the Chemical
Society has been published. It is almost entirely taken up
with abstracts of papers published in other journals.

Messrs. R. Friedi..\nder and Son have sent us their
XatutiC NovitaUs, Nos. 14-19, 1894, and No. xxx. of the
quarteily list of their new publications. The lists are invalu-
able to those who wish to keep in touch with recent scientific
literature.

The Quarterly Journal {'Ha. 201) of the Geological Society
contains several papers on the geology of Africa. Dr. J. W.
Gregory describes the glacial geology of Mount Kenya ;
Captain II. G. Lyons, the stratigraphy and physiography of the
Libyan Desert ; and Mr. H. Draper, the principal physical and
geological features of South-eastern Africa, and the occurrence
of dolomite in South Africa. There are seven other papers in
\.\\cJourniil, and sixteen plates.

We have received parts iv. to vii i. of the ihird volume of
the Transactions of the Leicester Literary and Philosophical
Soctcly, extending from July 1S93 to July 1S94. The Society
holds general meetings, at which lectures of a more or less
popular character are given, and sectional meetings for the
r.:ading and discussion of technical papers. Its object is to
cultivate literature, science and art, and, judging from the
reports, good work is being done in each of these directions.

It is well known that Dr. A. Bernthsen's " Text-book of
Organic Chemistry " is an excellent elementary account of the
principles o( organic chemistry. Dr. George McGowan's trans-
lation of the work, published by Messrs. lllackie and Son, was
reviewed in these columns in December 1S89 (vol. xli. p. 172).
A second English edition, revised and extended by the author
and the translator, has now appeared. It is virlnally a trans-
lation of \\\i fourth German edition, published last year, and
therefore various chapters have been recast in order to include
new developments ol t.lcir subjects.

November 8, i 894J

NATURE

Messrs. K. and J. Beck have just issued an illustrated
catalogue of microscopes, object-glasses, and other apparatus
for which they are famed. In it we find descriptions of micro-
scopes, from the larjje binoculars (which some investigators
declare to be almost indispensable for certain researches) to the
smaller instruments sui'able for bacteriological and clinical
work, and the useful petrological micro.-copes. The microscope,
like the telescope of the present day, bristles with innumer-
able accessories, and Messrs. Beck's catalogue appears to contain
most of these adjuncts. A copy of the catalogue will be sent,
post free, on application.

The Report of the Weather Bureau of the United States for
the year 1893, which has just reached this country, shows that a
general reorganisation has been effected, and that the work has
been carried on saccessfuUy. A very important publication of
the results of observations during 1891 and 1892, from upwards
of 2000 stations, has been recently issued. Every means is
taken to popularise the science ; the daily weather map is now
issued at seveniy-two stations of the Weather Bureau ojtside of
Washington, the na. nber distributed ana lally being over two
and a half millions. The circulation of the weekly weather
crop bulletins of the State services has also greatly in-
creased ; and continues to be the most valuable feature
of State weather service work. A large number of rail-
way companies co-operate with the Bureau in distributing
the daily weather forecasts by telegraph over their lines, and
whistle-signals are used to a considerable extent in some States.
The subject of seasonal forecasts is receiving the careful
attention of the Bareau, since the meteorological service of
India has indicated a path by which useful results can perhaps
be reached. The report also states that Prof. Bigelow continues
his studies of magnetism with sufficient prospect of success to
jastify the time and labaur expended. The library of the
Bureau now consists of nearly 20,003 books and pamphlets,
and the bibliography of meteorology comprises more than
65,000 titles.

Cultivators anJ admireri of roses will be interested in
" Rhodologia "^a discourse on roses and the odour of rose —
by Mr. J. C. Sawer, published by W. J. Smith, North Street,
Brighton. Too much attention is generally given to the de-
velopment of colour, form, and size of the fljwer, little heed
being paid to the great variety of perfumes generated in the
beautiful petals. .Mr. Sawer says thit there are experienced
gardeners who can discriminate many varieties of roses in the
dark, recognising them by their perfumes. The pure odour of
rose is best represented by Rosa Damasccna, Miller, and R.
centifolia, Lin. The art of distilling roses appears to have
originated in Persia, and dates from about 1612. In 16S4 it is
certain that otto of rose was manufactured on a large scale at
Shiraz. Octo of rose was known in Europe, however, about
forty years sooner than in the East, where its manufacture was
first practised. We learn that at the present day the odorous
products of the rose are extracted in Bulgaria, France, Ger-
many, and to some extent in India, Persia, Tunis, .■\!geria,
Morocco, and Egypr. The rose cultivated in Bulgaria for the
otto is a variety of R. Damaictna — the red dam.ask rose. R.
centifolia, which in English gardens is grown as the cabbage
rose or Provence rose, is cultivated commercially in the south
of France. Mr. Sawer brings together in his pamphlet a m.iss
of details of interest to students, as well as to manufacturing
chemists and buyers of rose products. Rose growers (both
amateur and professional) should certainly read " Rhodologia."

Two remarkable substances, carbazide or carbonyl nitride.
CONj, the nitrogen analogue of phosgene gas COCl^., and
di-urea, C0(XII. XIIjXO, the carbonyl derivative of di-
NO. 1306, VOt,. S l]

hydrazine, are described by Prof. Curtius and Herr Ileidenreich
in the current Bcrichle. The former compound, which is con-
stitutionally formulated CO(N3).j, is found to be readily pro-
duced when the recently described hydrochloride of carbo-
hydrazide, CO{NII . NIIjHCl)^, is treated with a cold aqueous
solution of sodium nitrite. The reaction is a relatively simple
one, proceeding according to the equation : —

CO(NH . NHjHCI), + 2NaN0o = C0(N3).j + 2NaCl -f 2HjO.

Carbazide as thus produced is a colourless oil of most explosive
character. It explodes with great violence when merely
touched. When the oil is dissolved in ether, and the solution is
allowed to evaporate over calcium chloride, the pure substance
CONc i* '^f' '"^ 'o^g brittle crystals, which usually explode
spontaneously in a bright light, but may occasionally be pre-
served for some little time before disruption. The substance is
extremely volatile, and the vapour possesses a most penetrating
and stupefying odour, reminding one simultaneously of phosgene
gas and azoimide, N3H. Its composition is readily proved by
saponification with alkalies, which convert it into salts of azoi-
mide, which can be precipitated by silver nitrite. It also
reacts with aniline in alcoholic solution to produce carbanilide
and free azoimide. The second compound described in the

.NH.NH.
communication, di-urea, CO /CO, is produced when

~NH. NH/

NH . COOC2H5
the compound | , also recently described by

NH . COOCoHj

Prof. Curtius, is heated to 100° in a tube with hydrazine
hydrate. Di-urea crystallises readily from water in monoclinic
prisms melting at 270°. It behaves as a strong monobasic acid
«hich is capable of expelling carbonic acid fiom carbonates.
The ammonium salt, C-jH^N^O^ . NMj -f HoO ; barium salt,
(CoH3NjO.,)2Ba-r3H.jO; silver salt, C.HjNjO.Ag ; and diam-
monium (hydrazine) salt, CoHjN^O^, . N.jHj, have been prepared
and analysed. It is a very stable substance, quite dilTerent in
this respect from the explosive carbazide above described.
When heated, however, with concentrated hydrochloric acid in
a sealed tube to 1 50' it is decomposed into carbonic acid and
hydrazine.

CO(NH . N1I)X0 -I- 2H3O = 2CO., -1- 2N„Hj.

The hydrazine remains combined with the hydrochloric acid in
the form of a chloride, presumably diammonium chloride
NoH^CI.

The additions to the Zoological Society's Gardens daring the
past week include a Brown Capuchin {Cebiis fiUiielltis) from
Guiana, presented by Mr. Graham S. Pownall ; two Common
Marmosets (Hapaie jacchus) Uom South-east Brazil, presented
by Mr. D. B. Macdougall ; two Black-backed Jackals {Cants
mesoinelai) from South .\frica, presented by Mr. Claude
Soulhey; three Crossbills [Loxia curvirostra), two Parrot
Crossbills {Loxia pilyopsittacus), an European White-winged
Crossbill {Loxia bifasciatus), a Yellow Bunting (Emberiza
aureola), two Northern Marsh Tits {Panis boreilis) from
Russia, presented by Captain A. Newnham ; a Double-ringed
Dove {Tiir/tirbiton/uahis] horn Java, presented by the Hon.
Rose Hubbard ; a Black Salamander (Sjlamandra atra),
European, presented by Mr. Maurice Suckling ; a Bonnet
Monkey {Macaciis sinicns) from India, two Lions {Felis
Uo, i 5 ) from Africa, deposited ; a Golden Plover {Charadritts
fluvialis), three Dunlins (Tringa alfina), European,
purchased ; a Spotted Pigeon (Coliimba maculosa), a Tri-
angular-spotted Pigeon (Culumba«uinea), two Vinaceous Turtle
Doves ( Turlur vinoieus), bred in the Gardens.

40

X.i TURE

[November 8. 1S94

. OUR ASTRONOMICAL COLUMN.

A Comet on the Eclipse Photographs of 1893. — A
year ago I'rof. Schaebeile ann mnced that the eclipse photo-
graphs taken by him at Chile in April 1S93, showed a comet-
like structure in the corona near the sun's south pole. The
photographs taken by ihe British observers in Brazil and Africa
were examined in order to see if they showed the cometary
object, but nothing could then be made out. It is well known,
however, that faint objects can be easily found when the
observer knows what can be seen, and where to look for it.
Prof. Schaeberle and Prof. Iloldenwere confident that a comet
was photographed upon the corona of the 1S93 eclipse, and,
with the ilea of obtaining confirmation of the discovery, the
latter sent Mr. \V. H. Wesley copies from negatives obtained
at Chile and Brazil, having marks upon them showing the exact
position of the object in question. These guides have fulfilled
their purpose, for Mr. Wesley says, in the Olsenalory, that
Ihey clearly point out a cometary structure in the corona. The
object is ex'remely faint, and, unless particular attention is
drawn to it, appears like a forked coronal ray. Evidently the
only way to prove ihat the object was really a comet was to
measure its angular distance from the moon's limb on the photo-
graphs taken at the different eclipse stations. Mr. Wesley has
done this, and he finds that the distances are: Chile, 29';
Brazil, 36'; Africa, ±47'. Tnerefore, it is concluded "the
evidence of motion relatively to the sun, given by the compari-
son of the plates taken at the three stations, seems to place the
nature of Prof. Schaeberlc's intetcsling discovery beyond a
doubt."

The Tra.nsit of Mercury. — The transit of Mercury across
the sun on Saturday, November 10, is a matter of more interest
to American than to European astronomers. The planet will
enter upon the sun's disc at 98' from the North point, counting
towards the East, and will leave at a point 50' from the North,
counting towards the West. It will reach the sun's limb at five
minutes to four in the afternoon ; but as (he sun sets at Green-
wich about twenty minutes later, there will not be much oppor-
tunity for observation in London. In America, however, if
the weather is favourable, the planet will be observed during
the whole of the five hours it will take in transiting. The
following are the Greenwich Mean Times of the phases of the
transit : —

Ingress, exterior contact

Ingress, interior contact

Leait distances of centres (4 26""8)

Egress, interior contact

Egres.s, exteri.>r contact

Nov. 10

3 55 3>-2
3 57 ■5'4
6 33 4«-5
9 10 264
9 12 io'4

MiRA Ceti. — Mr. Fowler writes from South Kensington to
draw attention to the (act that this remarkable variable will be
suitably placed for observations during its progress to Ihe next
maximum. .According to the Ct'w/<;///i'« to thi Ohscrvatory^ the
dale of minimum was September 24, and the maximum may be
expected about Febrmry next. It will be of great interest to
obtain a spectroscopic record during Ihe rise lo maximum, with
special reference to the lime ol appearance of the bright lines of
hydrogen, which have been seen near Ihe time of maximum.

Mr. Fowler observed the spectrum on October 24, with ihe
three-foot reflector, and it did not then differ from the spectrum
of such a star as a llerculis, in which the hydrogen lines are nol
known to appear bright. The bright part of the spectrum
which is coincident wih Ihe carbon band near A 5165 was rela-
tively leu bright, however, than when it was observed near the
lut maximum.

Return of Encke's Comet.— It is reported that Encke's
comet was observed at Rome by Prof. Cerulli, near the
predicted place, on November I. According to a search
cphemeti- given in Ihe Asliononiiic/it Naclirichleii, No. 3260,
for Berlin midnighi, the cornel's place for November 8 is
R.A. 22h. 59m. 30s. Decl. -(- 12° 32' 18 . The comet passes
perihelion next February.

Two Variahle Stars.— In a Wohingham Ohicrvatory
Circular, No. 40, daled Oc ober 30, the Kev. T. E. Espin
says: "The vaiiabiliiy of two red stars, R.A. oh. 49'om.
Decl. -f 58' r and R.A. ih. 498m. Decl. -I- 58' 46' has been
definitely ascertained."

NO. 1306, VOL. 51]

OBSERVATIONS OF MARS.

A L.\RGE proportion of the October number of Astronomy
•^ <j«i/ Astro-Physics is devoted lo articles on Mars, illus-
trated by several coloured plates. Schi.iiarelli's map ol Mars
forms Ihe frontispiece ; Prof. Schaeberle contributes nine
drawings of the planet ; and there are three plates containing
drawings made at the Lowell Observatory, Flagstaff, .\rizona,
by Mr. Percival Lowell, Prof. W. II. Picketing, and Mr. .\.
E. Douglass. The following statement, from an article by Prof.
Pickering, is a chronological summary of Ihe more important
facts and discoveries relating 10 .Mars. It is chiefly compiled
from Flammarion's monograph on Mars, and should be of
special interest at the present time : —

272 i!.c. The first known observation of Mars is recorded
in Piolemy's Almagest.

1610. The phases of Mars were discovered by Galileo.

1659. The first sketch showing surface detail was made by
Huyghens. He also suggested a rotation in 24 hours.

1666. Cassini determined Ihe rotation of Mars to take place
in 24 hours 40 minutes. lie also observed the polar caps, and
" be distinguished on the di.sc of Mars, near the terminator, a
while spot adv.mcing into the dark portion, and representing
without doubt, like those of the moon, a roughness or irregu-
larity of the surface." This latter statement is curious, but the
effect was undoubtedly due lo irradiation, since his telescope
was entirely inadequate to enable him lo observe such a delicate
phenomenon.

1777. With the exception of Huyghens, Hooke, and pos-
sibly M.iraldi, no one succeeded in making recognisable
sketches of Ihe surface detail upon Mars for over a century,
until Sir William Herschel took the matter up in this year.

1783. -Sir William Herschel delected Ihe variation of the
size of the polar snow caps with the seasons, measured the
polar compression, and determined Ihe inclination of the axis of
the planet to its orbit.

17S5-1S02. Schrmter made an extended study of the planet.
His drawings are upon Ihe whole rather belter than those of
Herschel. He discovered among other things the very dark
spots to which Prof. Pickering has referred in his publications
as the Northern and Equatorial Seas. He, however, supposed
them lo be clouds.

1S40. Beer and Maedler published the first map of the
planet, assigning latitudes and longitudes to Ihe various mark-
ings. On this map are indicated the first canals, and the first
of the small lakes, so many of which have been discovered
during Ihe last few years. The canals are Nectar and
Agathodaemon and portions of Hades and Tartarus. The lake
is Lacus Phoenicis. Their map is the first satisfactory repre-
sentation of Ihe entire surface of the planet. The only region
whiih previous observers had clearly distinguished was that in
the vicinity of the Syrtis Major.

1858. Secchi made a careful study of the colours exhibited
by Ihe planel.

1862. Lockyer made the first series of really good sketches
of Ihe planel, showing all the characteristic forms with which
we are now so familiar. His drawings, and also those of some
of the other observers, give the first indications of the appear-
ance of Ihe central branch in Ihe V, so called by .Secchi.

1864. Dawes detected eight or ten ol ihe canals.

1867. Huggins delected lines due lo Ihe presence of water
vapour in the spectrum of Mars.

1867. Proctor determined the period of roUation of Mars
within 01 second.

1877. Hall discovered the two satellites of Mars.

1877. Green made a very excellent series of drawings of the
planel, superior to anything which had preceded them.

1877. Schiaparclli made Ihe first extensive Iriangulation of
the surface of the planet, and added very largely lo the number
of known canals.

1879. Schiaparelli detected the gemination of Nilus, the
first known double canal.

1S82. .Schiaparelli discovered numerous double canals, and
announced that the appearance formed one of the characteristic
phenomena of the planet.

Mr. Percival Lowell reports ihc observations of Mars made
at the Lowrll Observatory, in continuation of those recorded in
our issue of September 13. The subjoined abstract of Ihe paper
raises some interesting points. The suitability of the site of the
observatory may be judged from the fact that the planet has

November S. 1894]

JV.-l TURE

41

been observed at FlagstaHf every night, with buc fe»v exceptions,
since the beginning of June. British astronomers would like to
be blessed with similar favourable opportunities.

A noteworthy feature of Mr. Lowell's previous paper was
the large area occupied by the dark regions on Mars, while
those singular, tilted peninsulas that are so generally repre-
sented connecting the continents wiih the island, to the south
were conspicuous by their absence. At that time one continuous
belt of bluish-green stretched unbroken from the Hour-glass
Sea to the columns of Hercules, or rather to where this pass
should have been, for it wasnat visible. Now (September lo)
the continuity is cut. Hesperia has reappeared, and it has done
this in just the way we should expect it to show were it land
drying off by a sinking of the general water level. Simul-
taneously, the region formerly occupied by the polar sea and
the region to the north of it from having been blue, has now
become for the most part reddish yellow. This reappearance
of Hesperia and change of colour of the regions farther south
is not due to increasing distinctness of vision consequent upon
the nearer approach of the two planets. Had Hesperia been
then of anything like the brightness it is now it could not have
been invisible. Furthermore, Eridania is at present one of the
brightest parts of the disc, not only as it comes round into view,
but in mid-career acro-s. East, and mt least in significance,
the polar sea has shrunk to a thin line in keeping with the
diminished size of the polar cap itself. All this water has gone
somewhere.

What may be the condition of these seemingly amphibious
lands, whether they be marsh chiefly water at one time and
dry land at another ; or whether their dark colour be due lo
vegetation which sprouted under the action of the water, and
then died when it withdrew, is a moot point. Mr. Lowell's
opinion is that it is half and half; that the transference of
the water is chiefly a surface one, and that the layer of water
is almost everywhere so shallow as to be soon drained off. His
reasons for believing the aqueous circulation to be a surface one
are many. In the first place, with the exception of certain
peculiar appearances near the south pole, there is no evidence
of anything like clouds or mist observable upon the planet,
nor has there been since the oljservations began. On the con-
trary, all parts of the surface seem to be revealed unveiled.
For an aerial circulation the only supposition at all feasible
is thought to be that of a heavy, nigh'ly dew, advanced by Prof.
Pickering. There ari strong reasons in the probable constitu-
tion of the Martian atmosphere for believing this possible. But
in view of certain facts connected with the canals, and referred
to later, the dew theory seems to be improbable.

As to how much of the dark areas are water, and how much
vegetation, there is as yet no evidence to decide. Prof. Picker-
ing has made some ingenious polariscopic observations to this
end, but the difliculties inherent in the process are such as to
preclude definite answer as yet. At first the polar sea seemed
to show evidence of polarisation, confirming what we knew
before of its watery character. Later the lakes, polar sea, and
dark areas alike revealed no trace of it. Inasmuch, then, as
there is every reason to suspect the polar sea, at least, to be
water, we are left in doubt as to the adequacy of the instru-
mental means to detect at present such minute phenomena.

Since Mr. Lowell's last paper, irregularities have been de-
tected at Flagstaff in the Martian terminator. These fall for
the most part under two heads, of which one is practically new.
It consists of certain polygonal flattenings first observed on Tune
30 by .Mr. Douglass. Since then these irregularities have become
so conspicuous that it is now difficult not to see one of them
in the course of an hour's observation. Sometimes they show
as simple slices shaved oft" the terminator, a paring of the
plaiiet s surface ; sometimes they appear bordered by enclosing
projections. They range from twenty to forty degrees wide.
But the suggestive thing about them is that they show almost
iQvariably upon that part of the terminator where the darker of
the dark regions is then passing out of sight.

At first sight it might seem as if the observed appearance
were directly due to the darker areas lying at a lower levsl than
the rest of the surface. But the connection is not so simply
direct. For Mr. Lowell points out that were it due to a zone
of low-level lying between zones of higher al'itude, it could be
observed only as a limb effect in this case still farther diminished
by the cosine of the phase angle, a quantity far too saiall to
be observable.

Nor will variations in slope explain the phenomemn. For

NO. 1306, VOL. 51]

to have an area show as a depression on account of its slope,
either the areas on both sides of it must be rising in altitude,
or the area itself must be falling in height, and this state of
affairs could not go on for ever unless the surface were an im-
possible spiral. So that the persistency of this flattening is
thus unaccounted for.

Prof. Story has suggested that these dark areas have
smooth surfaces such as water would have. In this case,
remarks Mr. Lowell, the reflection from them, by which
alone they would be perceptible, would diminish much
more rapidly from the centre to the side than would be
the case with regions having rough surfaces, such as deserts.
It may be added that though a rough surface, properly
constructed, might obliterate itself by its own shadows, this
could not happen to either a desert or a forest or a grass-grown
plain.

The second kind of irregularities are projections, or small
notches, such as are visible upon the lunar terminator ; only
that the Martian ones are much less pronounced. They are
probably due to mountains which seem to be of no great
height. The first of these was observed by Mr. Douglass on
June 30. An especially prominent one he noted on .\ugust 19.
It consisted of a projection flanked by a long shadow'cutling
into the planet obliquely. He measured the shadow's length
at 35". Taking the obliquity into account, this seems to imply
a range the length of whose projection would be about 2". It
is difficult to say how much of this is due to irradiation ;
especially as each observer differs. The best tests Mr. Lowell
has been able to make give a probable average of about five-
sevenths of a tenth of a second of arc with the power then
applied, about 640. Calling the terminal projection of this
range therefore 'is", its height appears to be about 3700 feet.
But the smallness of the quantity measured and the uncertainty
of the factor of irradiation renders the result largely indefinite.

A consequence of the slope on the effect of these mountains
is interesting. For an elevation need not appear as such.
What would show as a projection on the nether side of the
terminator would appear as a depression on the hither one.

Interesting plateaus were observed on two occasions by Prof.
Pickering. One of these lies in Phastontis not far from the
columns of Hercules, which thus seem to have been most
appositely named. Both plateaus rise abruptly, are surprisingly
level on top, and stand at about the same height, a height
which from the reduced measurements does not probably exceed
2600 feet.

On Mars the second kind of irregularity is less common than
the first, and the elevations indicated are apparently never
what we should call high. We may therefore conclude that
the Martian surface is, as compared with our terrestrial one,
rel.atively flat.

Certain avhitish pitches have been observed on the planet,
first by Prof. Pickering on .\ugust 16, and subsequently several
times by both Prof. Pickering, Mr. Douglass, and Mr. Lowell.
Prof. Pickering calls them clouds. To .Mr. Lowell, appear-
ances thus designated are of two kinds. The one, certain
whitish, flocular patches not far from the pole, may possibly
be cloud ; for they present a peculiar aspect, not like snow, nor
yet like terra firina. No motion, however, has been seen in
them. The others are merely certain bright spots on the general
surface of the planet. These are not whitish, but yellowish,
and will probably do very well for the more arid, dried-up tops
of the land. They likewise do not move, and, furthermore,
show always the same appearance day after day as regularly as
their regions come round. Many of them were equally con-
spicuous at previous oppositions, and have been chronicled by
various observers. Their contours are neither shifty nor indis-
tinct, but as sharp-cut as those of any other region.

Most suggestive of all Martian phenomena are the canals.
Were they more generally observable, the world would have
been spared much scepticism and more theory. They may, of
course, not be artificial, but observations made at the Lowell
Observatory indicate that they are. For it is one thing to
see two or three canals, and quite another to have the planet's
surface mapped with them upon a most elaborate system of
triangulation.

In the first place, they were, at the season of writing, bluish-
green, of the same colour as the seas in'o which the longer ones
all eventually debouch. In the next place, they are almtst
without exception geodetically straight, ^upernaturally so, and
this in spite of tlieir leading in every possible direction. Then

42

NATURE

[November 8, 1894

they are of apparency nearly unirorm width throui;hout their
length. What they are is another matter. Mr. Lowell thinks,
however, that the mere aspect is enou:;h to cause all theories
about glacia'iun lissures or surface cracks to die an instant and
natural death.

Bat it is their singular arrangement that is most suggestively
impressive. They have every appearance of having been laid
out on a definite and highly economic plan. They cut up the
surface of the planet into a network of triangles instantly sug-
gestive of design. \Yhat is more, at each of the junctions there
is apparently a dark spol. This feature seems to be invariable,
as, on closer appioach, junction after junction turns out to have
one. The larger of these appear on Schiaparelli's chart as
lakes. But there would >eem to be a small infinity of smaller
ones. A short half-hundred of them were seen at .\requipa in
1892, and others have recently been detected at Flagstaff. For
example, an important new canal, which runs from the western
end of the sea of the Sirens to Ccraunius, and which in view of its
pointof departure Mr. Lowell is induced to call the Ulysses, passes
through three of these small dark spots on the w.ay, one at each
junction. One of these was seen at Arequipa and elsewhere
in 1S92; the other two are new discoveries. The region of
the Lake uf the Sun is especially fertile in canals. In one of
the drawings which accompanies the paper here summarised,
thirty-one canals are to he seen, counting each line between
junctions ss a separate canal. Of these seventeen are amon ;
those in S>;liiaparelli's chart, while fourteen are not. Of the
twelve lakes m the figure, five are not down on his chart. This
is thought not, in general, to be the result of change, though
changes there apparently have been after proper discount has
been made for dilTerence of observations and of drawing. First
and foremost, the Golden Chersonese has vanished ; the land
of Ophir now forms the continental coast-line. Secondly,
Icaria has entirely altered in contour, resembling now an open
fan about the Phccnix lake for pivot. Pli.-eioniis has shrunk
to one-third of its former width — as represented in Schiaparelli's
chart. Eosphoros no longer enters Phoenix lake at the point
opposite Pyriphlegeihon, but farther to the west. Hut the
strangest transformation of all is that of the Phasis, which has
apparently obligingly become two (not geminated in the
technical sense) to suit both the old and the new state of
things. There is now a canal running in the same direction as
the old Phasis, but not to the southern end of Phxnontis ; and
there is another one running to the southern end of Phxtontis,
but not in the same direction as heietofore. This attempt to
carry out two apparently important ends by self-multiplication
is not a common characteristic of inanimate nature — a point
which Mr. Lowell holds is worth consideration.

Mr. A. Stanley Williams contributes lo the November
Oliienatoiy an account of his observations of Murs up to
October 20. With regard to the canals Mr. Williams says: —
" By taking advantage of every favourable opportunity, fifty-
one canals have been observed up to the present time [Oc' ober 20].
These include most of ihose shown in Prof. Schiaparelli's latest
map that could be properly observed at present, and in addition
thiec ihers not maiked in the map. Generally speaking there
is no difficulty in certainly identifying the canals, wiih the
exception of a few which are situated far north, and con-
nequently arc loo close lo the limb to be distinctly observed.
The general accuracy of the map is very sti iking, and I have
often been strongly impressed by the very thorough manner in
which Prof. Schiaparelli's work has been done. It is most rare
to come across the trace of a canal not marked in his map,
and the posilions of objects arc usually very reliable."

In the October number of our contemporary, Mr. Williams
stated that Phison was probably double. Later observations,
however, have shown it to be only single, the apparent gcmi-
nalion being probably caused by the existence of a feeble,
unrccoided canal running paiallcl to it, and about midway
between it and the coxst bordering the Kaiser Sea. Agatho-
dxnion and Ainxes were seen intensely double on three or lour
nights in September. Chrysorrhoas was also seen double, but
thiA canal appeared as an inconspicuous object comparcrl with
Agaihodxmon and Ataxc. In .September Mr. Williams saw
AiDenihet at a narrow inconspicuous and apparently single
canal. At ihe beginning of dclobcr, however, the object
appeared as a very brr>a<i, dusky, double canal. Ganges is
another broad, cons))icu<>us double canal, ihe duplicity of which,
accoKling lo Mr. Williams, is so obvious .as to be apparent
on almost any night on which obtcrvations are potiible.

Referring to the small dark spots designated lakes, Mr.
Williams says: — "Several more of these curious dark spots
have been seen. Lacu~ Phoenicis on a good night appears as
a small, nearly round, almost black spot, resembling the shadow
of a satellite of Jupiter when in transit. On one night a feebler
companion spot was seen just preceding it. Lacus Tilhonias is
a similar definite and nearly black spot, with a feebler com-
panion following it. In a fine drawing of Mars, dated Septem-
ber 5, Mr. Cammell shows Lacus Moeris as a minute datk spot,
with Nepenthes as a narrow definite line, and so I have ■■een
them on several nights lately. Lacus Tritonis is a similar
spot. At the junction of the canals .■\menthes (following com-
ponent), Thoth, and Astapus, there is also a little dark spot.
The dark spot at the north end of the Ganges, known as Lacus
Luna;, has been rather perplexing. On several nights there
was an evident appearance of duplicity about it, though it was
impossible to say with certainly in which direction it was double.
.\t length, however, the mystery was cleared up, the lake
having been seen distinctly double on September 29 at right
angles to the direction of the Hydraotes. The streak or bridge
dividing the lake into two was bright yellow."

The varying appearances presented during October by the
Mare Cimmeiium, and the extensive region lying to the north of
it, leads Mr. Williams to think that a great development of
cloud or mist has lately taken place on Mars. His observations
suggest "that cloud and mist formations are much more ex-
tensive and common on Mars than is generally considered to be
the case."

THE ELECTRIC CONDUCTIVITY OF PURE
WATER.

"T^ME difficulties besetting the preparation of water free from
•'■ the last traces of dissolved impurity cannot be better
illustrated than by the attempts which have been made to .tscer-
tain the electric condutiivity of the pure liquiil. At the outset
it has to be remembered that the conductivity of water is ex-
ceedingly small. As the result of the most recent observations it
has been found that one millimetre of water has at o' almost the
same resistance as 40,00x3,000 kilometres of copper cf the same
cro-s-seclioii ; consequently a copper wire having the same re-
sistance and sectional area as one millimetre of water would be
long enough to encircle the earth one thousand times. From
the difficulty of preventing the introduction of small quantities
of dissolved material into ihe water, and from the large diminu-
tion which such impurities exercise upon the resistance, there is
proljably no physncal constant for which such widely varying
values have been given as for the electric conductivity of water.
If the conductivity of mercury be taken as 10"', prior to 1S75,
the followin;j values had been ascribed to water by the
observers named ; — 80, Pouillet ; 70, Hecquercl ; 15, Oberbeck ^
4'S, Koseiti ; 216, Quincke; and \"a, Magnus. In 1875,
Kohlrausch succeeded in reducing the observed conductivity to
071, or a value only i/i2oth of that given by Pouillet. The
large diminution thus brought about was no doubt due, for the
most part, to the improved methods employed in obtaining
purer samples of water. In Kohlrausch's experiments pains were
taken not only lo remove organic matter and any volatile
alkaline or acid impurities from the water, but also to ensure
that in its subsequent treatment contact with glass was avoided,
the purified water being distilled through a platinum condeiiser
into a platinum resistance-cell. The next important modifica-
cation in the treatment of tlie water was again introduced by
Kohlrausch in 1S84. The whole of the above measurements haJ
been made upon water distilled under ordinary conditions, and
thus in presence of air; he therefore proceeded lo ascertain what
alteration in conductivity took place when the water was
rendered air-free. For this end he employed a glass apparatus
resembling in construction the so-called "water-hammer." A
glass bull) of some liOcc. capacity, which served as a retort,
was connected by a glass tube with a small glass receiver fitted
with platinum eltclrodes. In this receiver the resistance of the
waler was measured by the use of a galvanometer and a con-
tinuous current, as the latter was so feeble that no appreciable
effect was produced by polarisation. The glass connecting-tube
was provided with a vertical branch, through which waicr, or
liquids 10 clean the appar.alus, could be; introduced. Having
admitted a quantity of purified water into the bulb, the vertical
lube was then connected with a mercury air-pump, the pump

NO. 1306, VOL. 51]

November 8, 1894]

NATURE

43

set in action, and the water repeatedly shaken. A flask of
cooled sulphuric acid was also put into communication with the
evacuated enclosure to absorb water vapour, and thus proniote
partial distillation of the water. When dissolved gases had
been removed, the vertical tube was sealed, and water was then
distilled from the bulb into the receiver, the former being im-
mersed in a bath at a temperature of 30° to 40°, and the latter
in a cooling mixture at from o' to -8', the temperature being
kept as low as possible in order to diminish the solvent action
of water on the glass. The value obtained in this way for the
conductivity at iS' was o'25, or a number which is practically
only one-thiid of that given by water distilled in air.

Small as this number was, it was not supposed to represent
the actual conductivity of water, because experiment showed
that the conductivity altered rapidly with the time, owing to the
dissoluiion by the water of material from the glass receiver, and
from the electrodes. The correctness of this supposition is
strikingly verified in a communication recently made by
Kohlransch and Heydweiller to the Berlin Academy of
Sciences {Silzun^iberichls, March 1S94). One of the pieces
of apparatus used in 1SS4, and described above, had been
allowed to stand filled with water for some ten years, and,
apparently from long coniact with the water, the glass has
become much less soluble than it is under ordinary circum-
stances. Indeed, during the time necessary for an observation
the conductivity does not alter appreciably, and onl^ rises by
O'oi in a day. The method of experiment employed is similar
to that just described, the main modifications consisting in
additional precautions to obtain the water air-free, and in
freezing the purified water nrior to its introduction into the
apparatus. This method of freezing, suggested first by Nernst,
is of value in eliminating volatile impurities which might distil
over wi'h the steam. The smallest value now found for the
conductivity is '0404 at iS°, or a number which is only i/20ooth
of the original value given by Pouillet, and only one-sixth of
that obtained in the satue apparatus in 18S4.

Since with eacli improvement the value for the conductivity
has been largely reduced, the question which naturally arises
in connection with this last result is, how closely can it be sup-
posed to approximate to the truth ? Indeed, seeing that the
conductivity is so very small, it might fairly be suspected that
absolutely puie water is itself a non-conductor, and that the
observed conductivity is merely due to the presence of a slight
trace of impurity. As it seems almost itnpo-sible to answer this
question by purely expeiimenial methods, theoretical ails have
to be employed, and by means of the hypotheses involved in the
new theory of solutions, Kohlrausch and Heydweiller proceed
to show that pure water is actually a conductor, and that its
conductivity can be ascertained from their observations. The
method they employ is briefly as follows: — .\ccording to Art-
henius, if water is a conductor, the leason for this is that certain
of its molecules exist dissociated into the ions li and OH.
Moreover, the magnitude of the conduciivity depends upon two
factors : firstly, on the number of dissociated molecules ; and
secondly, on the velocities with which the ions travel. The
conductivity varies with the temperature becaue the number of
dissociated molecules, as well as the ionic velocities, increases
with the temperatuce. Krom these theoretical views, although it
is not possible to estimate the actual value of the conductivity, yet
the rate at which it should vary with the temperaiuie may he
ascertained. For, in the first place, according to van'i HolT,
the extent of the dissociation should vary with the temperature
just as it does in a dissociating gaseous system ; and in the
second place, the velocities of the ions II and OH may readily
be obtained at different temperatures from measurements on
dilute aqueous solution-, such as those of KOH, IICl, and
KCl.

Now, Kohlrausch and Heydweiller measured at 18° the tem-
perature-rate of change for a series rf samples of water of
different degrees of purity, and also the conductivity of two
samples of very pure water at temperatures between - 2'' and
50°. They then assumed that the observed conductivity was
really a sum, being composed of the conductivities of pure water
and a dissolved impurity. They were thus enabled to show
how it is possible, by making use of the rate of change as
deduced by theory for the single temperature of iS°, to obtain
from their observations theconductivity of pure water at dilTerent
temperatures.

The first result arrived at, is that the temperature- function of
Ihe conductivity over the entire range from - 2° to 50' agrees

NO. 1306, VOL 51]

within the limits of the experimental errors with the function
predicted by theory. This, as the authors remark, is one of
the most remarkable confirmations yet adduceil of the validity
of the hypothesis of the new theory of solutions. The second
and the most important conclusion for the question under
discussion is, that at 18° the conductivity of pure water has
in all probability the v.ilue 00361. The smallest value
actually observed, it will be remembered, was 0^0404. The
impurity present in the sample affected the conductivity,
therefore, by o'oo43, or by some 10 per cent. If this
impurity were of the nature of a salt, as in all likelihood
it is, the amount which would exert this effect would not
require to be more than a few thousandths of a milligram per
litre. We have here, therefore, the remarkable result
that an impurity of this nature, if present to the extent of
only a few parts per thousand million, is capaVjle of influencing
the conductivity by as much as 10 per cent, of its value. This,
together with what has already been said, leaves little question
that of all the physical constants of water, there is none which
is so sensitive to small traces of dissolved impurity as its electric
conductivity. J. W. Rodger.

NEO-VITALISM}-

\ QU-\RTER of a century ago, du Bois-Reymond headed
"^ the revolt of Mechanicalist Biology against the Vitalism
of Johannes Miiller. From Bichat to Magendie, from Johannes
MUUer to Schwann, the pendulum swung backwards and for-
wards ; but it was reserved for du Bois-Reymond, in his now
famous Berlin addresses, together with Ludwig and Helmholtz,
to expose the fallacies of vitalism, and establish physiol ogy on
a mechanical basis.

In the present address he takes up arms against the "new
vitalism," which since the discoveries of Heidenhain r/ activity
of cell in secretion -Jenus mere mechanical diffusion, has made
a new departure, based on a partial misconception of these
secretory activities. The position of the debate as it now stands
will be best shown by an abstract of Prof, du Bois-Reymond's
recent manifesto.

From Descartes and Leibnitz, until they encountered their
first opponent in Magendie, vitalistic theories were paramount.
During this period "vital force" was conceived as the attribute
of the sou! ill distinction to the body, or confused with the so-
called *' nervous principle," with animal heat or electricity.

Johannes Miillerand .Schwann again fought out the question ;
even the discovery by Schwann of independent cell-life in the
organism failing to convince MuUer that his views were
erroneous. The overthrow of vitalism was reserved for Ludwig,
whose autographic methods strengthened the physical side of
experimental physiology. He came forward as the champion
of anti-vitalism, and tlie same position was taken up by many
of Muller's immediate pupils. The fundamental dilference
between this and aU previous criticism lay in the physico-mathe-
maiical training of the antagonists, which enabled them to
delect the Trfonov <1>eCSos of vitalism. This prime error is
the misconception of '* force." Force is not an entity existing
apart from matter ; it is ultimately a mathematical concept,
standing for the physical changes which alone can be known 'o
us. The atoms are not a truck to which the forces can be
harnessed ; their attributes are eternal, integral, inalienable.
Helmholtz said that without a rational conception of nature,
scientific research would have no meaning ; vital force, how-
ever, is unthinkable.

The fundamental distinction between organic and inorganic
bodies has not been adequately recognised. In crystals, and
dead bodies generally, matter is in static equilibrium, stable,
indifferent, or labile ; in living organisms, tr.e equilibrium is
dynamic. As in heat, .and electrical diffusion, ihe rise and fall
ol current is balanced ; there is constant metabolism. And
metabolism, as well as the conservation of energy, present
insuperable difficulties to the vitalist. Heat and muscular work,
ciliary and amxboid movements, not least electricity, cannot be
generatett in animals otherwise than by conversion of potential
into kinetic energy, by oxidation of carbon and hydrogen. For
this nutritive matters— air, warmth, moisture, and for plants
light (the " integrating stimuli" of J. Miiller) are indispensable

* " Ucber Neo-Vitalismus." Von du Bois-Reymond. Silzungs Uericbtc der
Akademie dcr Wissei)scli:iften zn Ljcrlin. Oefiuiulicfie Sitzuug^iir Fcicrdcs
Lcibnizischen Jahrcslagcs voiii 38 Juni, 1894.

44

NATURE

[November 8, 1894

conditions. And we must farther compare the speed of organic
processes with those of the crjstal — quiescent to all eternity,
unless disturbed by external forces. One of the finest concep-
tions of modem science is that the dynamic equipoise in the life
of the individual corresponds to the cycle of living matter in all
nature.

Labile equipoise is, however, preponderant in the organism.
And here is the simplest explanation of the rciction which
MuIIer held peculiar to living beings — excitability. The specific
energies yielded up by living things in response to stimulus,
amount to nothing more than the mechanical reaction of
stored-up energy which we find, *.:,'., in a chronometer. A re-
peating clock, in its specific reaction to stress or strain, heat or
cold, moisture or dryness, electrical or chemical influences, pre-
sents a close analogy to the living muscle.

-V final blow, it seemed, was dealt to vitalism by Darwin's
" Origin of Species." which, through natural selection and the
sur^Mval of the fittest, accounted rationally for existing variations.
Thus the controversy was to all appearance ended. Of late,
however, on anatomical rather than on physiological grounds, a
new school of vitalism has arisen. By a somewhat strained
conclusion from the labours of Schwann and Heidenhain, it is
asserted that the processes deriving from element.il organisms
are too vast in relation to the latter to be accounted for on
mechanical principles. .-V more satisfactory rationale for
heredity is also demanded.

Prof du Bois-Reymond dismisses in a few words the argu-
ments of Driesch and Rindfleisch (1SS8-93). In regard to
Bunge (" Lehrbuch der physiol. Chemie," 18S7), he pomts out
that the " activity behind which lies the mystery of life " is
only static equilibrium of the organism, dependent on in-
legraiing stimuli, and reducible to a physical equation. In
fact, it is metabolism, maintained by chemical processes, which
convert potential into kinetic energy. We have here the Ttfinov
i(<rSi)t of the older vitalism, for it matters little whether we
deal with the comparatively .simple problem of fifty years back,
or, with Driesch and Bunge, search into the cell and its atoms,
or their yet unknown final particles. Impassable, indeed, are
the limits of our knowledge, but let us confine our i^totabimus
10 its proper frontier.

To the first contention of Keo-vitalism, du Bois-Reymond
opposes the molecular theory with its infinitesimal particles of
matter ; for the last, he refers us to the current controversy
between Weismann and Herbeit Spencer. There is, doubtless,
room for criticism of the Darwinian theory. For instance,
natural selection fails to account for the appearance of organs
such as the poison-fangs of snakes or the electric organs of
fishes, which are useless in the struggle for existence until fully
developed. But if Darwinism were fore-doomed, and exposed,
in the words of Herr Driesch, as "a cheap and specious
deception, " it is improbable that Xeo-Vitalism would reap any
benefit. There may 1 e still another solution to the problem.

Now, a* before, we stand in (ace of the unsolved riddle,
Origin of Being, with all the wondrous chain and intricacies
of development. Yet as an alternative to supernaturalism, we
can conceive one primordial act of creation whereby the germ
of life inherent in matter could develop by its intrinsic laws
into the brain of a Newton. Thus, with no day of creation
the whole order of nature would evolve mechanically, without
intervention of Old or New Vitalism.

And so we return upon the ideas of Leibnitz, save that
Materialism replaces Supernaturalism, inasmuch as we may
conceive that infinite matter, with its qualities as we know them,
has been circling in infinite space from all eternity.

Frances .\. Welhv.

SCIENCE IN THE MAGAZINES.

pROF. A. \V. RtCKER contributes to the Forlnishlly tl
■'■ brief sketch of the work of von Ilclmholtz. Our readers
are familiar »ith the investigations carried out by this eminent
phy!iicist ; nevertheless, the two concluding paragraphs of Prof.
Riicker's article sums up the chief of them so admirably as to be
worth quoting here.

" lie was one of the first to grasp the principle of the Con-
lervation of Energy. He struck independently, and at a criti-
cal moment, a powerful blow in its defence. \\: penetrated
further thin any before him into the my«lery of the mechanism

NO. 1306, VOL. 51]

which connects us with external nature through the eye and the
ear. He discovered the fundamental properties of vortex
motion in a perfect liquid, which have since not only been
applied in the explanation of all sons of physical phenomena,
of ripple marks in the sand, and of cirrus clouds in the air, but
have been the bases of some of the most advanced and preg-
nant speculations as to the constitution of matter and of the
luminiferous ether itself.

" These scientific achievements are not, perhaps, of the type
which most easily commands general attention. They have not
been utilised in theological warfare ; ihey have not revolution
ised the daily business of the world. It will, however, be
universally admitted that such tests do not supply a real measure
of the greatness of a student of nature. That must finally be
appraised by his power of detecting beneath the complication
of things as they seem, something of the order which rules
things as they are. Judged by this standard, few names will
take a higher place than that of Hermann von Helmhollz. "

In ihe same magazine Sir Robert Ball discusses the possibility
of life in other worlds— a subject that has a curious fascination
for the unscientific, but upon which the author throws the light
of modern scientific knowledge. "No reasonable person
will," he thinks, "doubt that the tendency of modem research
has been in favour of the supposition that there may be life on
some of the other globes. But the character of each organism
has to be fitted so exactly to its environment that it seems in
the highest degree unlikely that any organism we know here
could live on any other globe elsewhere. We cannot conjec-
ture what the organism must be which would be adapted for
residence in Venus or Mars, nor does any line of research at
present known to us hold out the hope of more definite know-
ledge." The verdict thus appears to be "possible, but not
probable," and the subject therefore stands where it did.

Mr. R. S. Gundry contributes to the same magazine an
article on Corea, China, and Japan ; and Mr. \. H. Savage-
Landor one on Japanese people and customs ; while Mr. G.
Lindsay describes his rambles in Norsk Finmarken.

Prof. N. S. Shaler contributes to Scrihnet an interesting
paper on " The Horse," the text being illustrated wilh pictures
by Delort. He dots not speak very highly of the animal's in-
telligence. In his words : " The nirntal peculiarities of the
horse are much less characteristic ihan its physical. It is,
indeed, the common opinion, among those who do not know
the animal well, that it is endowed with much sagacity, but no
experienced and careful observer is likely to maintain this
opinion. All such students find the intelligence of the horse
to be very limited. Although some part of this menial defect
in the horse, causing its actions to be widely contrasted wiih
those of the dog, may be due to a lack of deliberate training
and to breeding with reference to intellectual accomplishment,
we see by comparing the creature wilh the elephant, which
practically has never been bred in captiviiy, that the equine
mind is, Irom the point of view of rationality, very feeble." It
is worth remark, however, that a good deal of misappre-
hension exists as lo the intelligence of the elephant. According
to the best authorities, though elephants are docile and
obedient, their intellecual capacity is below that of most other
Ungulates. Colonel H. G. Piout contributes his second article
on " English Railroad Methods," giving a number of interesting
facts respecting passenger and freight traffic, cost of
construction, &c. , in England and .\merica.

Colonel A. G. Durand shows, in a paper in the Conlem-
forary, that the southern region of the Eastern Hindu Rush is
one lull of interest. In the J/uiihiiiilaiiaii, St. George Mivatt
writes on " Heredity. " A portiait of the author forms the
frontispiece of the number Mr. Grant Allen continues his
moorland idylls in the English Illiislraliii, his subject this
month being house-martins.

Chamhiri's 7.'«/;m/ contains its usual complement of chatty
articles, among which may be mentioned " Feathered Archi-
tects," "The Infinity of Space," and "The Vanishing Eland,"
Loni^mans J/<i;-,j:(»;f reprints an address, " How to Make the
Most of Life," delivered by Sir B. W. Richardson before the
Literary and Scientific Section of the Grindelwald Conference
this year. The Rev. B. G. Johns writes on " The Injuries
and Benefits of Insects " in the Sunday Magaunc, and the Key.
T. R. K. Slebbing contributes an instructive article on certain
Crustacea to Good iVurdi. The latter magazine also contains an
article on tea, by Mrs. A. H. Green, and a well-written ex-
planation of the laws of motion, by Emma Marie Caillard.

November 8, 1894]

.V^ TURE

45

UNIVERSITY AND EDUCATIONAL
INTELLIGENCE.

Oxford. — The examiners for iheBurdett-Coutts Scholarship
have reported that no candidate of sufficient merit has pre-
sented himself for examination. The Scholarship, therefore, has
not been awarded this year.

There will be an election to a Geographical Studentship of
the value of ;^loo at the end of Hilary Term, 1895. Candi-
dates should send in their names to the Reader in Geography,
I Bradmore Road, Oxford, before Wednesday, February 27,
1S95.

The Savilian Professor of Astronomy, Prof. H. H. Turner,
will lecture in the Schools on Thursday, November 8, on the
subject o( the Transit of Mercury on Saturday, November 10.

In a Convocation held on Tuesday, November 6, the degree
of .Master of Arts, by decree of the House, was conferred on
Robert Warington, F.R.S., Sibthorpian Professor of Rural
Economy.

CAMBRIDGE. — The Cavendish Laboratory Syndicate have
presented a report on the pressing needs of the department of
experimental physics. It appears that a large laboratory for
elementary classes and an additional lecture room, together with
certain accessory rooms, are urgently required. To erect and
furnish these on a suitable scale would require some ^10,000.
As the University is unable to meet any such expense at present,
it is proposed to put up part of the building at an expense of
^4000, of which half can be provided from the accumulated fees
of students working in the laboratory. The Financial Board
think that ;/^2ooo more can be obtained from the Common
University Fund. Mr. Fawcett, the architect, has prepared
plans for the work, which are to be seen at the Cavendish
Laboratory.

The Sedgwick Memorial Museum Syndicate state that the
tenders for the building designed by Mr. T. G. Jackson,
A. R. A., have been some ;i'45oo in excess of the estimate based
on the architect's calculations. They are reluctantly forced to
the conclusion that the University cannot afford to supplement
the Memorial Fund to the required extent, and they accordingly
ask powers to reconsider the plan, or to substitute a new one
for it.

At the annual election to Fellowships at St. John's College,
on November 5, Mr. H. C. Pocklington was one of the success-
ful candidates. He was bracketed Fourth Wrangler 1S92, was
placed in the first division of the first class with Mr. Cowell,
the Senior Wrangler, in Part II. of the Tripos of 1S93, and this
year gained one of the Smith's Prizes, the other falling to Mr.
Hough, also a scholar of St. John's. Mr. Pocklington presented
a dissertation on the periods of the vibrations of a vortex-ring
constituted by fluid cuculating round a hollow core, in which
the periods of the unsymmetrical vibrations are for the first time
determined. The analysis also included a determination of the
effect which an electric charge would produce on the vibrations
and the stability of a vortex atom in a rotational ;ether. In a
minor investigation, which will appear in the next number of
the Proceedings of the Cambridge Philosophical Society, the
forms assumed by two parallel cylindrical hollow vortices moving
steadily through fluid, and the character of the surrounding
motion, are investigated in detail.

Mr. S. Sand^irs has bequeathed to the University ;ii'2000 for
the endowment of a Reader in " Bibliography, paleography,
typography, bookbinding, book-illustration, and the science of
books and manuscripts."

As the result of the prolonged discussion on post-graduate
study in the University, the Council of the Senate have
sanctioned a grace for the appointment of a syndicate to con-
sider (I) the best means of giving further help and encourage-
ment to persons who desire to pursue courses of advanced study
or research within the University ; (2) what classes of students
should be admitted to such courses ; aud (3) what academic
recognition, whether by degrees or otherwise, should be given
to such stutients, and on what conditions.

Mr. Herman, of Trinity College, has been appointed Chair-
man of Examiners for the Mathematical Tripos, Part I.

Dr. Forsyth, F.R.S., Sir K. S. Ball, F.R.S., R. T. Glaze-
brook, F. R.S., and Prof. G. B. .Mathews, have been appointed
I'xaniiners for Part. II. of the Mathematical Tripos.

Prof. Ewing, F. R.S., Prof. Osborne Reynolds, F. R.S., and
W. N. .Shaw, F.R. S., have been appointed Examiners for the
Mechanical Sciences Tripos.

NO. 1306, VOL. 51]

Dublin. — The med.als in Natural Science, given at
Moderatorship, have been awarded as follows : — Gold medals to
R. A. Rossiter and T. B. Jobson ; silver medal to C. W.
Orpen. The Professor of Botany's prizes for practical work on
the Gymnosperms, to be accompanied by sections and draw-
ings, have been given to T. B. Jobson, for work on the
anatomy of the young stem of Ginkgo biloba and on the repro-
ductive organs of Ta.xiis haciala ; and to R. A. Rossiter, for
work on. the floral development of Thuja plicata a.od Larix
Ettropea.

Lectures on the Experimental and Natural Sciences for
Michaelmas Term commenced on November 2. Prof Reynolds
lectures on Inorganic Chemistry, Prof. Fitzgerald on Heat,
Prof. Sollas on Mineralogy and Physical Geology. Prof.
Mackintosh lectures on Zoology, and gives demonstrations on
Comparative Anatomy. Prof. Wright lectures oa Algje and
Fungi, and gives a series of demonstrations on the Vascular
Cryptogams. The assistant to the Professor of Botany, Mr. H.
Dixon, gives a course of Laboratory instruction on vegetable
cells and tissues.

The special courses in Natural Science for 1S95 are in Geology,
the Cambrian Period ; in Zoology, the Invertebrate Heart ;
in Botany, the Natural Orders, Cruciferje and Papilionacex.

The Anthropological Laboratory has reopened for the session
1S94-95. Dr. C. K. Browne will, under the direction of Prof.
D. Cunningham, give, on three days in each week during
Term, demonstrations on Anthropological Methods. These
will be open to all students.

Assisted by a grant from the Royal Irish Academy, Dr. C. R.
Browne visited, during the long vacation, the district of North
Erris, in the county of Mayo, believed to be one of the most
primitive regions in Ireland. The anthropological results ol
this visit will in due course be laid before the Irish -\cademy.

The Dublin University Experimental Science Association held
its first meeting for its eighteenth session on the 6th iust. Prof.
Sollas delivered the opening address, in which he treated of
"Geological Time."

From a Return made to the Department of Science and Art,
and published last week, it appears that the total amount spent on
technical education during the year 1S92-93, in England, Wales,
and Scotland, was /'529,7i8, and that the estimated total
amount allocated to technical education for the year 1893-94
was ^^696,328. Forty-one out of the forty-nine county councils
in England are applying the whole of the residue received
under the Local Taxation (Customs and Excise) Act to technical
education, and eight a part of it to the same purpose. Of the
councils of the sixty-one county boroughs, fifty-three are devot-
ing the whole of the residue to technical education, and seven
a part of it. The thirteen county councils and the three county
boroughs in Wales and Monmouth are not only devoting the
whole of the residue to intermediate and technical education,
but six of them are also levying a rate, or making grants out of
the rates, for the same purpose. In the case of Scotland,
twenty-three out of the thirty-three county councils are applying
the available funds to technical education, and seven a part. Of
the 194 burghs and police burghs, however, 122 are applying
the whole to the relief of rates.

The Technical School Committee of the Birmingham
Corporation have appointed Dr. W. E. Sumpner, of the
Battersea Polytechnic School, from among seventy-five can-
didates, as Principal of the new local Technical School. The
salary is ;^50O per annum.

The extensive buildings that have been lately erected as an
addition to the medical school at the Owens College, Manchester,
were formally opened by the Duke of Devonshire, the President
of the institution, on Tuesday.

SCIENTIFIC SERIALS
American Meteorological JoHrnal, October. — The meteoro-
logical services of South America, by A. L. Rotch. In the
Argentine Republic there are now five stations of the
first order, forty of the second order, and one hundred
rain stations. The first of the AnnaUs was published
in 1878, and dealt with the climate of Buenos Ayres from
observations since 1801. In Uruguay there is one observatory
of the first order, at Villa Colon, near Montevideo, and in 1S90
a Meteorological Society was established, and publishes a

4°

NATURE

[November 8, 1894

monthly review. In Brazil, observations were made at Rio de
Janeiro, since 1S25. but no record of them is to be found until
1844 ; from this time sammaries have been regularly pu'ilished.
A Central Nfeleorological Department was established in 18SS
in connection wiih the bureau of the Navy, but the climat-
otogical service has not yet been organised. — The forecasting of
ocean storms, &c., by \V. Allingham. This paper was
prt pared for the International Meteorological Congress held at
Chicago in .\ugust last. It deals more particulaily with the
storms of the North .\tlantic, and the author shows that at
present any attempt to forecast them from America is not very
successful. Nevertheless, the Meteorological Office of Paris
continues to receive and publish dally reports from the United
States and Canada, as well as from steamers ariiving at
American ports from the .'Atlantic. — Sun-spo;s and Auroras,
by Prof. H. A. Hazen. The author has laid dosvn curves of
all the sun-spots measured i^n the Greenwich and India photo-
graphs from i88l to 1S8S, and also the auro:al numbers recorded
in the United States, and shows that auroras and sun-spots are
not concomitant or coincident phenomena. For the purpose
of inquiring into the annual range, the auroras and sun-spots
for twenty-three years have been summed for months. There is a
remarkable correspondence in these results; both phenomena
show a maximum in April, and the second maximum occurs in
Sep ember for auroras, and in October for sun spots. Prof.
Hazen considers that the investigation of sun-spots and auroras
is the most promising line that can be taken in a study o( the
post.ble cfTecis from some cosmical force upon our atmosphere.

Bullelin of Ihe American Mathematical So:iety, second
series, vol. i. No. i (October 1S94).— This is a continua-
tion of the Bulletin of the New Vork Society. The title
of the Society having been changed, as previously announced,
of necessity the title of the Bulletin is also changed. An
article on the " Summer meeiing of the American .Malhe-
ir.atical Si.citly " givis an account of the doings, and
abstracts of the _ papers read, at the August meeting
in Brooklyn, N.Y., of the .-Vmcrican .\ssociatit>n for the
Advancement of Science. The co-nperaliun of the two
Associations resul.ed in a succes-ful gathering for the younger
body. — Other aniclcs in this number are on the connection
between binary quarlics and elliptic func'ions, by Prof. E.
Study. This is an abstract of a paper which will appear in the
American Journal of Matliemalics. It shows how a certain
group of rational and irrational co-variants of a binary quanic
can be expressed as one-valued functions of one or two para-
meters, thus filling up a number of lacunx contained in former
presentations uf the subject. — Reduction of the resultant of a
binary quadric and «-ic by virtue of ils semi-coiiibinant
property, by Prof. H. S. White. The author discusses the
partial problem solved by Clelisch, viz. to write in symbolic
form the resuliant of a binary quadric and a binary quantic of
arbitrary order //. The method employed is novel, and illus-
trates the utility of the theory of conjugate forms. — Next a list
of astronomical papers read at the American Assiciation meet-
ing (see supra), is given, and short abstracts supplied. Notes
and new publications complete this number.

Ameriean Journal of Mathematics, vol. xvi. No. 4 (Balti-
more, October 1894). — "Sur la transformation des courbes
alt,ebiiqucs," by E. Gour^at (pp. 291-298), discusses two
geneialiiaiions of a theorem demonstrated by Liiroth (Math.
Annal. ix. p. 163). The rest of the number (pp. 299-396) is
taken up by a master. y memoir on isolrnpic el.istic solids of
nearly spherical form, by C. Chrcc. It is preceded by a full
table o( contents, and has 320 equations. The author remarks
that the Investigation of a solution of the elastic solid equations
for the tquilibrium or motion of homogeneous isotropic
material enclosed by the simplest of all surf.-ices, the spherical,
presents no small difliculiy. Eor even a slight departure from
the spherical form the increase of dilficuliy is so considerable
that, so far as I kno*, the only problem of the class success-
fully treated hitherto is that of a nearly spherical solid exposed
to gravilatioual force, but free of all surface force. In the case
considered by Mr. Chree, surface (orccs appear us well a> bodily
forces, so that the luciblem is much more (general than ihat pre-
viously treated. Mis method is novel, and ihe memoir closes
with some speculations as to the action of the sun on the earth.

Jlullettn dt la r Acn,i/mie Royale de Belgiijut, No. 8. — Note
CD Ihe suliject of a recent communication from M. Ch.
Ljigrange, by .\I. K. Kolie. The author claims to have been

NO. 1306, VOL. 5 ']

the first to announce that the theoretical period of initial
nutation would be found too short owing to the internal
fluidity of the globe, and that the best method for observing
this nutation would he that of observations at intervals of
twelve houis. He also state! that the vaiiations of latitude
would be equal and of opposite sign on two oppoite meridians
in the same heaiisphere, which was borne out by observations
in Europe and Honolulu. His hypothesis exjilainirg the
annual vacations is capable of explaining and estimating the
systematic difTererces between the ca'alogues of Greenwich and
the Cape, given by Downing, and by the diurnal nutation, the
differences between Paris, Pulkowa, and Washington, and
between Melbourre and the Cape. — On the origin of the
dicrotism and the undulations of the systolic plateau of arterial
pulsation, by Victor Willem. This work was undertaken in
order to decide whether any of the pulsations shown by the
sphygmograph and the recorders of arterial pressure have a
peripheral origin, or whether they all start from he heart and its
neighbourhood. Experiment* upon the carotid and crural
arteries of dogs show that the latter alternative is true. The
author further studied the influence of various injections upon
the pulsation.

SOCIETIES AND ACADEMIES.

LONDO.N.

Entomological Society, October 17. — Henry John Elwes,
President, in the chair. — Dr. H. G. Breyer, of Prajtoria,
Transvaal, South .-Vfiica, was elected a Fellow of the Society.
.Mr. G. C. Champion read a letter, dated .\ugust 15 last, from
Mr. J. V. Johnson, of Funchal, .Madeira, on the subject of a
recent visitation of locusts to the island, and exhibited specimens.
Mr. Johnson mentioned that Darwin, in his " Origin of Species,"
recorded that in November 1S44, dense swarms of locusts
visited Madeira. He said that since then, until .\ugust last,
these insects had not visited the island, Mr. Champion re-
marked that the species was Dccticus alhijrons, Fabr.,
not a true migatory locust. Mr. Champion also exhibited
specimens of /J »;M«.i(d nitiUula, I'elleius dilala'us ani .4thom
rhombeus, taken by himself in the New Forest during the past
summer. — Mr. 11. Goss read a letter received from Captain
Montgomery, J. P., of .Mid Ilovo, Naial, reporting vast flights
of locusts there, extending over three miles in length, on .-Vugust
31 last, and exhibited a specimen of the locust, a species 01
Acridium. Captain Montgomery stated that, as a rule, his
district, like m^ si of Natal, was free from the pest, but lli.it an
exceptional invasion had occurred in 1S50, — .Mr. J. W. Tuti
exhiiiitcd four typical specimens of Einydia crihrum from the
New Furest, and, for comparison, four specimens ol the variety,
Candida, of the same species, taken at an elevation of 4000 feet,
near Courmayeur, on the Italian side of Mont Blanc. He stated
that he had also met with this form in the Cogne Valley, at an
elevation of from 6000 to 8000 feet. — .Mr. R. .\dkin exhibited
a specimen of Erelna •rthio/'s, in which the left fore wing was
much bleached, taken in August last, near Carnforth. Mr.
Adkin also exhibited a series of .Icrjiij'cta rumiiis from Co.
Cork, Ireland, including light and black forms, with examples
from theScilly Isles, Isle of Man, and North of Scotland for
comparison. — Mr. Elwes exhibited a series of Chy>noba.\ alberta
i 9 1 Chionohas uhleti, var. -aruna, and Erehia diicoidalis, from
Calgary, Alberta, N.W. Canada, which had been collec'ed in
May last, by Mr. Woolley-Dod. He said that the validity ol
C. alherta, which had been ques ioned by .Mr. W. H. Edwards,
was fully established by these specimens. — Prof. E. B. Poulton,
F. K..S., gave an account of the changes which he had recently
made at I ixford in the arrangement ol the Hope Collections in
the Department of Zool igy, and as to the rooms now available
for students woiking at these collections. — Mr. G. T. Bethune-
Baker communicated a paper, entitled " Descriptions of the
I'yralidx, Cramliidx-, and Phycid.e, collected by the late T.
Vernon- Wollaston in Madeira."

Paris.
Academy of Sciences, October 29.— M. Locwy in the
chair. — Experimenial verifications of the thcjry of weir?, with
either adtierent or partly submerged watir-shee', with regard to
the pressures, by .Nl. .1. Boussinesq. — On the existence in plants
of principles capalile of condensation with production of car-
bonic acid, iiy M.\I. Berthclot and G. Andre. Plant-leaves were

\

November 8, 1894]

NATURE

47

dried at llo°, reduced to powder, and then heated on an oil-
bath, at i2o'-l 30°, with 12 per cent, hydrochloric acid. The
work was carried out in an atmosphere of hydrogen. It resulted
in a slow evolution of carbon dioxide. This may be accounted
for on the hypothesis that the contained carbohydrates have a
ketonic constitutiin. Experiments on the simple carbohydrates
are in progress. — On the movements which certain animals
make in order to fall on their feet, when precipitated froii a
height, by M. Marey. Successive instantaneous photographs,
taken in two planes, are given of a cat in the act of falling.
The necessary movements are accomplished by the animal ro-
tating the forepart of its body when drawn in, so that its
moment of inertia is small as compared with that of the ex-
tended hind-quarters, and by this movement being repeated by
the latter when drawn in and the fore-part extended. — A note
concerning the above communication, by M. Guyon. It is
shown that the rotation of the animal is not contrary to received
laws. — Observations on the principle of areas, by M. Maurice
Levy. — Reduction of the equation of continuity in hydraulics to

the form — -^^', -- -fo— ' - 2p^i- 'v=0- An abstract of a memoir
dl as as as

by M. P. E. Touche. — The first volume of a work by M. G.
Hinrichs, "On the Mechanics of .Vtoms," gives adiscussion of
atO'Tiic weights and metho<is use.l in their determination, and
treats of the question of the unity of matter. — On the problems
of dynamics of which the differential equations admit a con-
tinuous group, by M. P. Staeckel. — On the differentiation of
trigonometric series, by M. Matyas Lerch. — On the constitution
of the electric arc, by M. L. Thomas. The arc between two
carbons containing metallic salts consists of a nucleus surrounded
by an envelope ; in the former are found the substances giving
band spectra, hydrocarbons or carbon vapour and cyanogen,
in the envelope metallic vapours from the dissociated salts pass
from the positive to the negative pole, and there burn in the
oxygen of the air, producing the metallic line spectra character-
istic of this region. — Relation between the miximum vapour
pressures of water, ice, and a saline solution at the freezing-
point of this solution, by M. A. Ponsot. — Oa the gaseous
products given off by wood charcoal when heated to a
high temperature out of contact of air, by M. Dosmond. —
On the transformation temperatures of irons and steels, by M.
Georges Charpy. — Kermesite, by M. H. Baubigny.— On the
superposition of optical effects of several asymmetric carbon
atoms in the same active molecule, by MM. Ph. .\. Guye and
M. Gautier. In a molecule containing several asymmetric carbon
atoms, each of them acts as if all the remainder of the molecule
were inactive. The optical effects of several asymmetric carbon
atoms in the same molecule are algebraically added to give the
optical activity of the molecule. — On the saturated hydrocarbons
with active amyl radicals, by Mdlle. Ida Welt. — On the estima-
tion of alcohol in essential oils, by M.M. Charles Fabre, Garrigou,
and Surre. — On the existence of cellules en panicrs in the
acinus and excretory conduits of the mammary gland, by .M. E.
Lacroix. — Observations on a note by M.M. Prillieux and
Delacroix. — On ihe goinmose liacillairc oi vines, by M. L. Daille.
— Culture of a fungus {CoUybia vclutipes) g,rov/iag on wood, by
MM, Costantin and Matruchot. — On the disease " Rouge " in
the Paris nurseries and plantations, by M. Louis Mangin.— On
the relations of the basalt and phonolite of the Sue d'Araules
(Haute- Loire), by M. Ferdinand Gonnard. — On the geology of
French Congo, by M. Maurice Barrat. — On several quaternary
grottos of the Dordogne, and on s.jme megalithic monuments of
Orne and La Manche, by M. limile Riviere.

New South Wales.

Royal Society, June 6.— C. Moore in the chair.— The
following papers were read : — Notes 00 some minerals and
mineral localities in the northern districts of New South Wales,
by D. A. Porter. — On the magnetic susceptibilities of specimens
of Australian basalts, by Prof. A. W. Riickcr, F.R.S. — On
boleite, nantokite, kerargyrite, and cuprite, from Broken Hill,
by Prof. Liversidge, F.K. S — -From number to quaternion, by
C. Fleuri.— New orbit of the double star 3 416 = Scorpii 1S5,
by Ptof. S. Glasenapp. — On the value of gravity at the Sydney
Observatory, by E. F. J. Love. — Preliminary notes on ihe
pharmacology of carissa ovata, var. stoloni/era. Bail, by Dr.
T. L. Bancroft. — On the almandine garnets from the Ilawkes
bitty sandstone at Sydney, by H. C. Smith. — Oa a natural
mineral spring at Bungonia, by Rev. J. Milne Curran.

July 4.— Prof. Threlfall, President, in the chair.— The fol-

NO. 1306. VOL, 51]

lowing papers were read :— On a transparent star-chart : a con-
venience for observers, by II, C. Russell, F.R.S. — .\borigina/
Bora held at Gundabloui in 1894, by R. H. Mathews. — Ob-
servations and orbit elements of comet Gale 1894, by John
Tebbutt. — On the structure and composition of some .\ustralian
basalts, by Rev. J. Milne Curran.

August I. — Prof. Threlfall, President, in the chair. — The
following papers were read : — On garbage destructors, by Prof.
Warren and Dr. .\shburton Thompson. — The geology of lime-
kilns, Bathurst district, by W. J. C. Ross. — The territorial
divisions of New South Wales into counties, by W. D. Camp-
bell.— On the timbers of New South Wales, by J. V. De
Coque. — On the -Aboriginal rock carvings and paintings in New
South Wales, by R. H. Mathews. — The Society's bronze medal
and money prize of £2^ were presented to each of the two
last-named gentlemen for their papers.

September 5. — Prof. Threlfall, President in the chair. — The
following papers were read : — Some stone implements used by
the .\borigines of New South Wales, by R. H. Mathews. —
Recent researches in the testing of cement, by W. S. de Lisle
Roberts. — A comparison of the languages of Ponape and
Hawaii, by the late Rev. E. T. Doane, with additional notes
and illustrations by Sidney H. Ray. — Preliminary note on the
structure of gold nuggets, by Prof Liversidge, F.R.S. Gold
nuggets on being cut through or sliced and polished, and then
etched by chlorine water, were found to exhibit well-marked
crystalline structure closely resembling the Widmanstatt
figures shown by most metallic meteorites, except that in the
nuggets the crystals are more or less square in section and show
faces which evidently belong to the octahedron and cube. On
heating the nuggets in a bunsen burner, blebs or blisters form,
on both the polished and unpolished surfaces, and on still more
strongly heating, these, in some cases, burst with sharp reports,
and pieces of gold are projected with considerable violence.
As no explosions have been observed on dissolving or eating
away the crusts of these blisters by chlorine water, it would
appear that the blebs are probably due to the vaporisation of
some liquid or solid substance. As soon as a fresh supply of
nuggets is obtained, experiments will be proceeded with to
ascertain definitely whether gold nuggets contain occluded
gases, or liquids or solids which are vaporisable. In slicing
some nuggets, scattered granules of quartz were met with
inside, although quite invisible outside, and at first it was
thought that the explosions might be due to the quartz ; but
the gas, in some cases, continued to issue from the burst bleb
(where the aperture formed was small) and forced the bunsen
flame out into la'eral jets, just as if urged by a blow-pipe.

Linnean Society, September 26. — Prof. David, President, in
thechair.^Oii the correct habitat o( Patella tirmajecenis, Pilsbry
{ = J'. PUsbryi, Braz. ), by John Brazier. The author expressed
the ooinion that this is the species referred to in Mr. Percy
Smith's pamphlet, " The Ker iiadec Islands : their Capabilities
and Extent" (Wellington, 18S7), which states that on Macauley
Island there occur '• large limpets (as big as small saucers, and
good eating)." — On a Trocims from Port Jackson, and new
varieties of Bulimus miltocluilus. Reeve, from the Solomon
Islands, by John Brazier. Under the name of Trochus Adamsi,
n.sp., was re-describcd a Port Jackson mollusc, the original
specific name of which ( 7". comptus, A. Ad.) is preoccupied for
a species named by Phillipi. Dr. Fischer also confounded T.
comptus, A. Ad., with the New Caledonian T. Poupineli,
Montr., which is a distinct species. Thn-e new varieties of
Bulimus millocheilus, R-evi-, were also described. — Observa-
tions on Dctidrolagus bennctlianus, De Vis, by Edgar R. Waite.
The author described ihe species from material recently
obtained from the Bloomfield River, Queensland. He was of
opinion that in respect of bjth external and anatomical
characters it is a well-marked species.

Amsterdam.
Royal Academy of Sciences, September 29. — Prof. Vande
Sandi: Bakhuyzen in the chair. — Mr. Beyerinck discussed the
reduction of sulphates by a specific sulphide (erment. This
suliject bears on two questions of general bacteriology, i.e. (l)
the production of sulphureited hydrogen, and (2) the power of
reduction. Bacteria may produce H.^S in four different ways :
Firstly, frim sulphur, this being dissolved, by the excretion of
ammonia, amines or alkahiids lorming sulphides, which are
(Kcompo ed by carbonic acid; secondly, from proteids con-
taining sulphur, well known in cases of putrefaction ; thirdly,

48

NATURE

[November 8, 1894

with
pep-

from sulphites and thiosulphates (the Utter of these substances
beioK decomposed into sulphites and sulphur, and the sulphite,
acted on as in the first case) ; fourthly, by the reduction of sul-
phate^. From the common reducing bacteria which turn nitrates
into nitrites, and these into ammonia salts, which produce from
litmus, indigo-blue, methylen-blue &c. the co7«P°°d^g
leucoids, none has the power to attack sulphates 1 his is dot^e
by a specific ferment, a ver>- small ,/,V;7/„.,, which 's perfectly
ansrobic, and which is common in the black mud of polluted
waters, as also in these waters themselves. It grows
veiv small quantities of organic nutriment, as malates,
tone, sugar, and phosphates added to common water, rendered
alkaline by sodium carbonate. Temperatures fr°«> ?5 '<> J°
are the best for reduction. For the determination of the Hjb
the iodometric method can be used. Common water with the
addition of ,', pef cent, sodium malate, ,',, per cent, asparagin,
-A- per cent, potassium phosphate, and i per cent, sodium car-
bonate. infected with mud containing the ferment, and secluded
from the air, and with forty-five milligrammes SO3 per litre, was
in three days quite free from this substance, containing nearly
10-2 miUigr. H,S, the cause of the deficit (twenty-one milligr.
SO,, not transformed into H.,S) being not yet 4""e clear
Mohr's salt (ferrous ammonium sulphate) is very well adapted
for reduction experiments, the smallest trace of reduction being
indicated by the form.-ition of black FeS. The spirillum has
been named 5>/r,/.';./« dcsullurica,,:. It seems to be of geo-
logical importance, inasmuch as the deep groundwater of the
province of South Holland is quite free from sulphuric acid
which, being abundant on the surface, is apparently reduced by

Farmers : A. E. Pease (Macmillan).-A Treatise on Hygiene and Public
Health, Vol -,(Churx:h,m. -The Deserts of Southern France, ' V<,U. . S.
BSng-GoulJ Mcthue„).-Sir Victor Brooke, Sportsm.ln and Na Ural s
O. dslie .Stephen .(Murray).- .,he_^Ioan.at.,.^c.f ^^^^J^ ,M-

igineering :

'* -l. a

Koch). -

Slorphologie der ErdoberrtSche. a Vols. : Ur. A. ^'="«,i?'""Xnd^ria!"
horn) —Twelfth Annual Rep ,rt of the t .shery Board for Scotland, 18J3,
Par" 3 . Sctentific Investigations (Edinbursh)^-Lectnrcs O" '."1= "^'J''"'""
The4y; Piof. A. Milnes Marshall (Nu.t). -Album von Papua-Typen . A.
15 Meyer and R. Parkinson (Dresden. Stengel). ,, >, v i> „„„

plMp.iLETS.-N.-uional Health: C. Sott (Belf.ast. Mullai, .-Report
on Experiments on the Manuring. of Hay, Oats, ^"f J"™PV n -Tb i7
The Pamunkey Indians of Virginia : J. G Pollard (^^^!;'^'"S';"K '''''"°
graphy of the Wakashan Langua^-es : I. CPdhng (Washington .

Skkials -Physical Soc ety of London. Proccedin.gs, Vol. xiii. fart i
(T^rior and Francis). -Journal, of An,-uomy .-.nd Physiology, October

Longman's Mag;

apposes , .__ ,

both the conduction and the displacement current give
rise to a //<j//effect, the intensity coeflicient being difterenl
the two cases. In this way the discrepancy, which exists

(New York, Macmillan) •

Bcilnige zur Uiologie der Pflanzcn. vn.

Milller).— -Morphologisches .lahrbuch, -■

fTivlnr and !■ rancisi. — lournai ui rtu..iw<"j and '^hysioiog>,
Unffin).-lour"al of the Royal Microscopical Soc ety, tXi'f" ('''"'»"';>■
Longman's Magazine, November (l.ong.nans),-Engl,sh Illustrated Maga-
i^n" November (i<,8 Strand) -Mineralogical Maga^me, September
(S"mpkm°-^S "day Magazine, November. Isbisler). -Good Words No-
ember (isbister).iAmerican Journal of M,a.hema.,cs. Vol- xv,. No 4
(Baltimore).-Bulletin of the .Wr.can Mathematical f""''^. O«ober

- L'Antbropologie, lome V. No. 5(t'ans, .Masson).

• Band, i Heft (Breslau. Max
Band, 4 Heft (Leipzig, Engel-

Z::^!:-^;^:^Zr^^S:<Si^^ survey n-j^-.; o^j^^-

,„„l —-rransactions of the Le cesler Liter.ary and Philosoplucal 3uciei>,
V'oYTpl^tr* 10 I (Leicester; Gibbons).-Z=itsch.ift (iir Wissenschaft^^^^^^
lo^ef Ivi,^ Band, 3 Heft (Leipzig, Engelman,;).-(-on.en.Porary Revtew.
November (Isbisler) -Natural Science, November (Macnullan).--Hum.an.-
"rian November (Hutchinson).-y.;arterly Journal of the GeoloB cal
Society Vol 1. Part 4, No. =oo (Longmans) -Geological Magaz.ne,
No"e',ibeT(S.anford).-Journalof the Chemical Society N-=-^=;, ^,';™=V
^nrt Tackson) —Geological Mag.izine, November (Paul).— ScribnersMaga
zine-'Not.ember (Low)!iNatural History of Plants : Kerner and Oliver,
Part' 7 (Blackie).--Fortnighlly Review, November((,hapman and Hall).

CONTENTS.

PAGE

and his own experiments. All mixtures of two substances mus
show retrograde condensation.-Prof. Onnes also communicated
the results of an investigation, by Dr. Borgesius, on the molecular
refraction and dispersion of some salts in solution, made with an
interferential refraciomcter especially constructed for 'his pur-
pose, and giving the small ditVerences of refraclion of two fluids
by a single reading of verniers and counting of striae.

Pattern Maker: "Helical Gears.'

BOOKS PAMPHLETS, and SERIALS RECEIVED.

s.-I.ehrbuch der Experimental Phy.sik : A. W.dlner, Erster Band

Ilcm-nt. nf Mrtallurgy : W. J. H.arnson and W J

k of Organic Chemistry : Dr.

(I.ei(zig. Teut.i

Harnson. J'l

Bemthsen, t;

.,.Murr..j i
i'amickc

;,, i vis, I

Dussinner of

.Mineral K*

ion). — U.S

.n, 2nd English edilion(Blackie) —
Chemistry: Dr. C. Schorlemmcr,
1) —Geoiiictrical Conies: C. Sinilli
,try of the Vertebr.itcs : A. Willcy
l-nre of Wm. Huckland. D.D.,
T iincllcn Hilfsmiltcl der Che-
XL, Bcclihold)— Arithmetic
. iiiversity Press) —Practical
1 I. II .\clon(Canibridge University
Britain: Dr. C. Creighlon, Vol. 1
Klrmcniary Introduction to Mine-
IVess).— Report of the Com-
Vol. I (Washington^.— Index
I, Part 3 (Oxford, Clarendon
. .: I'-ychologv : Prof. C. Lloyd
:ion Universclle: B. Conta (Pans,
■ t 11 July iS'jZ (Washington).—
, -,3: D. 1. Day (Washing-
-The Penokec |ron- Bearing

I -vii

Phi

l.e-
I>et
Ge
Th.
mrr

.(Lc
v. K.

, -ravl^ij- I
Dickft'in and A

r., |. r r.n.l I .

- and C. R. van Hi«

! ',c U.S.: S. H.

I , ; H. Gannett

ri'ilogv, 1 888.80 :

' ,• to tnc

.Spottis-

e Ilritish

.j.-|iie

.: in die

, . Cher).—

,fli.e .M.^...:. L.iCoiu..!ivc : M. 1 1 ..>-l..: . 1 ;.l.on; -Com-

Prof .Conner (.M.tcmillao).- Horjc-Brceding for

Tchad"
A Foreman

Dixon': "The Nests" and Eggs of Non-Indigenous
British Birds" • •„

Conner: " Commercial Geography •

Flalher: "Dynamometers and the Measurement ol
Power."— G :•■■„■

Guy : " Electric Light and Power

Letters to the Editor:—

Prc.f. Hollzmann and the Kinetic Theory of (jases.—

In° n"ive^zUu"udes. " (llimlraul)-^. s'. Buckman
lames Parkinson, the .Vuthor of " Organic kc,....ins ol
• a Former \Vorld."-Spencer George Perceval .
On Chinese Beliefs about the North.- Kumagusu

Th"piSoViimberT;ees.-/uVred- W.Bennett

Khyndiodcmui Urratris in Liiglanil.— I- . vv.

Gamble ■ ■

Tan-Spots over Dogs' Lyes.— J. Shaw . . . • ■

A Criticism of .he Astronomical Theory of the Ice

Age. By Edward P. Culverwell

Notes. (Illiislrat.J.)

Our Astronomical Column :— , , i, ,

.\ Comet on ihc- Eclipse Photographs of 1^93 . . . .

The Transit of .Mercury

Mira Ceti

Return of Encke s Comet

Two Variable S'ars

Observations of Mars . . . . ,.•,■;
The Electric Conductivity of Pure Water

Rodger .' ,«; 11. ' ' '

Neo-Vitalism. By Frances A. Welby . .
Science in the Magazines . . -^ •

University and Educationa Intelligence .

Scientific Serials

Societies and Academies • • • • • •

Books, Pamphlets, and Serials Received

29
30

30
30

30
30

3'

3«

3t

32
33

33

35

By J

W.

NO. 1306, VOL 51]

NA TURK

49

THURSDAY, NOVEMBER 15, 1894.

HISTORICAL EXPOSITION OF MECHANICS.
The Science of Mechanics: a Critical and Historical
Exposition of its Principles. By Dr. Ernst Mach,
Professor of Physics in the University of Prague.
Translated from the second German edition by Thomas
J. McCormack. (Chicago : The Open Court Publish-
ing Co. London : Watts and Co., 1893.)
nnHE appearance of a translation into English of this
J- remarkable book should serve to revivify in this
country the somewhat stagnating treatment of its sub-
ject, and should call up the thoughts which puzzle us
when we think of them, and that is not sufficiently often.
Prof. Mach isa striking instance of the combination
of great mathematical knowledge with experimental skill,
as exemplified not only by the elegant illustrations of
mechanical principles which abiunl in this treatise, but
also from his brilliant experiments on the photography
of bullets, which have been recently elaborated and
simplified by Mr. C. V. Boys.

The appearance of the first edition, in 1883, is stated,

I in the preface of the second edition, to have stimulated

I the production of treatises by WohUvill, Streintz, Lang e,

Epstein, MiiUer, Popper, Helm, Planck, Poske, and

others, discussing theories of cognition in connection

with Mechanics ; but it is curious that Maxwell's little

tract on "Matter and Motion," of 1879, a veritable

I master-piece on this subject, should appear to be unknown

to the author, although mentioned in the translator's

1 foot-notes.

j The present volume is not a treatise upon the applica-
I tion of the principles of mechanics, to quote from the
preface. Its aim is to clear up ideas, expose the real
significance of the matter, and get rid of metaphysical
obscurities. Mechanics is treated not as a branch of
mathematics, but as one of the physical sciences ; and
the reader's interest is invited to know how the prin-
ciples of mechanics have been ascertained, from what
t sources they take their origin, and to what extent they
may be regarded as permanent acquisitions. All this,
the positive and physical essence of mechanics, which
i makes its chief and high interest for a student of nature,
I is in existing treatises completely buried and concealed
j beneath a mass of technical considerations.

The gist and kernel of mechanical ideas has in almost

! every case grown up in the investigation of very simple

I and special cases of mechanical processes ; and the

I analysis of the history of the discussions concerning these

cases must ever remain the method at once the most

effective and the most natural for laying this gist and

kernel bare. Indeed, it is not too much to say that it is

< the only way in which a real comprehension of the general

I upshot of mechanics is to be attained.

Acting upon the plan laid down in the citations above,

i the author treats his subject from the historical order of

; development, and begins with an Introduction of general

remarks, illustrated by an Egyptian representation of

the mechanical arts, and by a quotation from Vitruvius.

Chapter i., on the Development of the Principles of
Statics and Hydrostatics, follows closely the historical
NO. 1307, VOL. 51]

subject-matter given by Lagrange in the first section of
his " Mc'canique analytique"; but Prof. Mach's treat-
ment has the very great superiority of being profusely
illustrated by elegant diagrams, while Lagrange made a
point of banishing figures entirely from the " .Mccanique
analytique."

Lagrange thus appears as a supporter of the ancient
tradition that Rational and Practical Mechanics were to
be considered as in a measure opposed to each other,
as Newton observes in his preface of the " Principia " ;
the latter being -an inferior branch of study, to be culti-
vated only for the sake of gain or some other material
advantage.

To quote from Rankine's Preliminary Dissertation,
prefixed to his " Applied Mechanics '' : —

"Archytas of Tarentuni might illustrate the truths of
Geometry by mechanical contrivances ; his methods were
regarded by his pupil Plato as a lowering of the dignity
of science. Archimedes, to the character of the first
geometer and arithmetician of his day, might add that of
the first mechanician and physicist — he might, by his
unaided strength acting through suitable machinery,
move a loaded ship on dry land — he might contrive and
execute deadly engines of war, of which even the Roman
soldiers stood in dread — he might, with an art afterwards
regarded as fabulous till it was revived by Buffon, burn
fleets with the concentrated sunbeams ; but that mechan-
ical knowledge and that practical skill, which in our eyes
render that great man so illustrious, were by men of
learning, his contempor.iries and successors, regaried
as accomplishments of an inferior order, to which the
philosopher, from the height of geometrical abstraction,
condescended with a view to the service of the State."

We have only to study the progress of the essentially
modern science of Electricity to recognise the eloquent
truth of Rankine's words, in inveighing against the medi-
asval and ancient fallacy that there is a double system of
natural liizvs, one theoretical, geometrical, rational, dis-
coverable by contemplation, applicable to celestial,
a;therial, indestructible bodies, and being an object of
the noble and liberal arts ; the other practical, mechanical,
empirical, discoverable by experience, applicable to
terrestrial, gross, destructible bodies, and being an object
of what were once called the vulgar and sordid arts.

Possessed with these prejudices, the scholar of ancient
and mediaeval times, and even of the present day, was
occupied in developing and magnifying the numerous
errors, and in perverting and obscuring the much more
numerous truths which are to be found in the writings of
Aristotle ; so that it is not surprising that the notion
arose of scientific men being unfit for the business of
life, and that various facetious anecdotes were contrived
illustrative of this notion, anecdotes which have been
handed down from age to age, and applied with little
variation to the eminent philosophers of every time.

Returning to chapter i. of Prof. Mach's treatise, we
find that the Principle of the Lever, employed in the
writings of Archimedes, is the real foundation of the
Science of Statics, and not the Parallelogram of Forces,
as is generally taught ; this theorem, although sketched
out by Stevinus of Bruges, was first fully enunciated by
Varignon and Newton, about 16S7. In fact, the modern
treatment of Statics is almost entirely due to Varignon.

Prof. Mach examines with the acumen of a meta-

D

50

NATURE

[November 15. 1S94

physician the weak points of a demonstration ; it is a

pity then that he seems unacquainted with Duchayla's
proof of the Parallelogram of Forces, which is unfor-
tunately so popular with writers on mechanics in this
country, as he would have revelled in pointing out the
weakness of a logic which prides itself above all things
on its rigour.

The Principle of Virtual Velocities, employed as funda-
mental by Lagrange in his " M<5canique analytique " in
preference to the principle of the Parallelogram of
Forces, was enunciated very clearly by Stevinus in its
application to systems of pulleys ; and here we are com-
pelled to call attention to a flaw in Fig. 39, r, the only
one that we have met in the course of the work ; the
system cannot possibly be in equilibrium with the central
portion of the thread askew, as drawn in the diagram.

The Principle of Virtual \'elocities is important in the
historical development of Mechanics as the first sketch
and shadowing forth of the modern Principle of the Con-
servation of Energy ; but it is unfortunate that the name
should still sur\-ive, as it is confusing and meaningless.
Prof Mittag Leffler was eloquent at the meeting of the
British .■Association at Oxford in his denunciation of the
habit of attaching to theorems certain names of indi-
viduals, real or quasi discoverers ; and he might have
qjoted the Principle of Virtual \'elocities as an instance
of the disadvantage of inventing a descriptive title of too
great generality to a newly discovered theorem.

Lagrange has attempted an experimental verification
of the Principle of \'irtual X'elocities, and it is a tradition
that an apparatus was constructed on these indications by
a former professor of mathematics at Cambridge. It is
probable that the description of this demonstration and
of the apparatus to be found in Todhunter's Analytical
Sialics was purposely ironical ; and that, in popular
language, Todhunter wrote this with his tongue in his
cheek, knowing the story of the sceptical student who
had tried the experiment himself

The demonstration amounts to proving that a certain
weight is no more likely to rise than to fall, and therefore
(here Todhunter says he follows Lagrange's words very
closely) the weight should remain stationary. The
student, however, found that the weight did not remain
stationary, and wanted to know why ; the professor told
him in confidence that it was prudent to make use of
an invisible pin to keep the weight in order.

This is not the only case in which it is desirable for
the professor to keep a card up his sleeve, as the saying
is ; in the Foucault experiment of the pendulum which
shows the rotation of the Earth, the slightest current of
air will destroy and reverse the desired motion ; so that
it is advisable in showing the experiment to have an
elastic ball concealed in the palm of the hand, which can
send a slight current of air on the bob of the pendulum,
and thus accelerate the initial precession of the plane of
the vibration so as to gratify the eyes of the audience and
diminish their impatience at the slowness of the motion ;
.ifterwards the motion can be checked so that the total
advance is made to agree with the theoretical result.
Very undignified and dishonest, some will say ; but the
experiment is otherwise bound to fail from its delicacy
>¥hen shown to a large audience, except under the most
favourable conditions.

NO. 1307. VOL. 51]

While Statics, both as a Science and an Art, can be
traced back through Archimedes and the existing monu-
ments of the Eg>'ptians, Greeks, Romans, and of medieval
architects, the Principles of Dynamics, discussed in
chapter ii., were first laid down clearly by Galileo ; and
the great fallacy to be destroyed before any real advance
could be made was that of the Aristotelians, who main-
tained that heavy bodies fall faster than light ones,
because the upper parts weigh down on the under parts
and accelerate their descent. But in that case, retoried
Galileo, a small body tied to a larger body, must, if it
possesses in se the property of less rapid descent, retard
the larger ; ergo a larger body falls more slowly than a
smaller body.

The entire fundamental assumption is wrong, as
Galileo says, because one portion of a falling body can-
not by its weight under any circumstances press another
portion; although, according to WohhviU (.Appendix I.),
even Galileo himself only very gradually abandoned the
Aristotelian conceptions.

But discarding all metaphysical argument, the Aristo-
telian fallacy was demolished once for all by the
cxpcrimailum cruets carried out by Galileo, of letting
bodies of different weight fall from the Leaning Tower
of Pisa, when all were found to take the same time of
descent ; any slight discrepancies were afterwards
accounted for by the resistance of the air.

A still more delicate experimental verification is to be
found in the pendulum, as pointed out by Galileo ; a
plummet at the end of a thread has the same period of
oscillation whatever be the weight or the material of the
plummet.

The theory of the pendulum, when composed of a body
of finite size, as required in a clock, was completed by
Huygens in his Horfl/ot^iumoscillaloriiim, 1673, in which
the mutual controlling influence of a number of separate
plummets is investigated when the plummets are rigidly
attached together ; and thus for the first time the idea of
a moment of inertia and of a centre of oscillation was
introduced into Mechanics. In his further researches
into the theory of the clock, Huygens was led to the
discovery that isochronisin for all amplitudes can be
secured by making the phiiiimet oscillate in a cycloid ;
and to do this practically he found that the thread must
wrap and unwrap on an equal cycloid, and thereby he
made the first step in the doctrine of evolutes and the
theory of the circle of curvature.

Having demolished the Aristotelian fallacies on falling
bodies, Galileo had still to determine the true laws ; his
first conjecture that the velocity grew uniformly with the
distance, or that v — gs, having proved untenable,
Galileo stumbled upon the true law that the velocity
grows at a constant rate, or that '' = gl.

The next step in the theory, to prove that in conse-
quence s — hgl', was not an easy matter for Galileo, who
sought in general an experimental proof of his theorems
(as, for instance, his attempted quadrature of the cycloid
by weighing it made in sheet lead) ; once this was
established, however, it was comparatively an easy matter
to demonstrate that the path of an unresisted projectile
is a parabola, and to prove it experimentally by rolling a
ball obliquely on an inclined table.

Galileo's difficulty was to measure lapse of time with

November 15, 1894]

NA TURE

51

t

exactitude, accurate clocks and watches not being in
existence in his day ; but he overcame this difficulty by
a modification of his own invention of the ancient
Clepsydra.

The laws of circular motion were next investigated
by Huygens ; and a combination of these laws with
Kepler's Third Law, on the assumption" that the planetary
orbits round the Sun are circles, leads at once to the
Law of Attraction varying inversely as the stjuare of
the distance.

This law, generalised into the Law of Universal
Gravitation, became in Newton's powerful hands the
foundation of his system of Natural Philosophy, in ex-
plaining not only the elliptic orbits of the planets in
accordance with Kepler's first two Laws, but also the
perturbations of these orbits as exemplified in the Lunar
Theory, and the Theory of the Tides.

Prof. Mach suggests in Fig. 139 a very ingenious ex-
perimental illustration of the tides on a body in free
space, like the Earth, as distinguished from the tides
which would be produced if the Earth was fi.xed, by
means of a small iron sphere covered with a solution of
magnetic sulphate of iron ; this can either revolve as
the bob of a conical pendulum in true planetary style
round the pole of a fixed magnet, representing the dis-
turbing Sun or Moon ; or it can hang suspended at rest
at a small distance from the pole, and thus illustrate
high water under the disturbing Sun or Moon, and low
water at the antipodes when the Earth is supposed
fixed. The discrimination of the two cases must be
considered one of the most brilliant parts of the
" Principia."

It is curious that Prof. Mach does not accept Newton's
distinction between the relativity of motion of translation
and the absoluteness of motion of rotation, illustrated
experimentally by Newton by means of a revolving
bucket of water suspended by a twisted rope (" Principia,"
Definition VIII. Scholium) ; and here we think he would
have been interested in Maxwell's arguments on Rota-
tion in § 104, Matter and Motion.

Maxwell proceeds to explain that it is possible, by
means of observation and experiment on or inside the
Earth alone (by Foucault's pendulum, for instance), to
disprove Milton's assumption, that it is evidently all the
same

" Whether the sun, predominant in heaven,
Rise on the earth, or earth rise on the sun ;
He from the east his flaming road begin.
Or she from west her silent course advance ; "

&c., although the geometrical configuration of the earth
and the heavenly bodies, so far as is discoverable by
astronomical observation, is the same on either assump-
tion.

In the Translator's Preface we are told that " Mr. C. S.
Pierce has rewritten § 8 in the chapter on Units and
Measures, where the original was inapplicable in this
country (America) and slightly out of date."

As might be anticipated, this means that we are now
to change the name of the quantity formerly designated
by the word weight, poids, gewicht, pondiis, and to use
the word mass instead.

But if a continental mathematician, Prof. Mach in-
cluded, is asked to give a numerical definition of the

NO. 1307, VOL. 51]

mass of a body, he replies, if in French, " poids divisd-
par g " : so that if a body weighs p kilogrammes, its mass^

is -, and the unit of mass is thus _§■ kilogrammes.

<r

\Vhen the gravitation unit of force was in universal'
use, it was considered an abbreviation to write m for

S and to replace the gravitation measures of momen-

tum and energy, 2^ and 2^ , by mv and ^mv".
g 2^

But when Gauss's abso'ute unit of force is employed,

the 'absolute measures of momentum and energy are ^z/-

and hi>v-, and the abbreviation of m for -^ is no longer

required; or if the letter m is employed, then p = m and
not mg, as Mr. Pierce asserts ; if the mass of a body is
:o kilogrammes, its weight in kg cannot be anything
except 10 kilogrammes.

But if with absolute measures we retain the equation
p = mg, and measure m in kilogrammes, then p, the
■weight or poids, is measured in one-;,nh parts of a kilo-
gramme ; this is contrary to all practice, and is absolutely
forbidden by the laws on Weights and Measures.

With gravitation units the weight of a body is at once
the numerical measure of the quantity of matter in the
body (Newton's quantitas materice) and of its gravita-
tion, or the force with which it tends to the Earth ; if a
body weighs/ kilogrammes, it is attracted by the Earth
with a force of / kilogrammes. The loose definition
usually given that " the weight of a body is the force with
which it is attracted by the Earth," is really no definition
at all, but a mere description ; it should at least be
amended to " the weight of a body is the number of
units of force with which the body is attracted by the
Earth" ; and it will be found that this definition is never
employed except with the gravitation unit of force ; so
that this definition merely asserts in a roundabout way
that the weight of a body is a measure of the quantity of
matter, as measured out by weighing against pound or
kilogramme weights.

It is incorrect to say that there are two systems of
measurement , the absolute and \k\e. gravitational (p. 2S4).
There is no practical method for the measurement of
forces in absolute measure with any pretence to accuracy ;
the absolute system is merely a system for recording
numerically the results of experiment ; the measurements
themselves are always made in gravitation measure, and
afterwards converted into absolute measure by multiply-
ing by the local value of g. There is thus no need for
absolute units with our insular British F.P.S. (foot-
pound-second) system ; and Prof. James Thomson's
poundal, although a convenient name, is of no practical
or theoretical use.

In experiments at Washington, the Paris gravitation
unit would not be employed, so that the statements on
p. 286 do not tend to clear up the subject. What appears
to be meant is that if a perfect spring balance could be
constructed such that a kilogramme deflected it at Paris
through 981 divisions, then when carried to Washington
the deflection would fall to gSo'i divisions, and if carried
to the Moon to about 164 divisions, but if carried to the
surface of the Sun the deflection would rise to about
30,000 divisions, provided Newton's " Law of Universal

52

NA TURE

[NoVEMBEK 15, 1894

Gravitation " is correct ; but the kilogramme weight
remains the same throughout the universe.

But if a balance could be constructed with its fulcrum
somewhere in the Azores, and the scale pans hanging
over Paris and Washington, then i kilogramme at Paris
would equilibrate i •00092 kilogramme at Washington
<p. 2S6).

It is sometimes asserted in our school-books on
Mechanics that a pound weight, if carried to the surface
of the Sun, would weigh about 30 pounds ; but if a
balance could be made to stretch between the surfaces
of the Earth and of the Sun, then a pound weight at the
Sun's end would be equilibrated by 30 pounds at our end ;
so that it is equally true to say that a pound weight on
the Sun will weigh 30 pounds on the Earth.

Prof. Mach would perform a great service if he would
extend his criticisms on the usage of the word pondus
by Huygens, Leibnitz, Wallis, &c., to modern times, as
great mystifications exist at the present day.

The C.G.S. system of units is explained by Mr. Pierce
on p. 385. These units are much too minute except for
recording delicate physical measurement. If Prof.
Johnstone Stoney's amendment of the M.K.S. (metre-
kilogramme-second) system had been adopted, we should
have a system incorporating the joule, watt, volt, ohm,
and ampi-re as units ; it is not too jate to make the
change ; the disadvantage that the density of water is
1000 in this system is more apparent than real.

Although the double system of natural laws mentioned
by Rankine is now exploded, we still have a double
system of instruction in mechanical text-books, one theo-
retical, geometrical, rational ; the other practical, me-
chanical, empirical, discoverable by experience. It
should be the object of modern science to break down
the barriers between these two systems, and to treat the
subject of mechanics from one point of view. Instead
of this, the gap between the two systems seems to be an
increasing one, insomuch that Prof. A. B. W. Kennedy,
m his inaugural address to Section G of the British
Association at Oxford, demanded for young engineers a
course of instruction in mathematics entirely different to
that imparted at present in our schools and colleges.

Some remarks at the end of Prof. Kleins Sixth
" Evanston Colloquium " may be consulted as bearing on
this question.

A careful study of Prof. Mach's work, and a treat-
ment with more experimental illustration, on the lines
laid down in the interesting diagrams of his Science of
Mechanics, will do much to revivify theoretical Mechan-
ical Science, as developed from the elements by rigorous
logical ueaiment. A. G. Greenhill.

NEIVTI/'S INORGANIC CHEMISTRY.
A Text-book of Inorganic Chemistry. By G. S. Newth,
P.I.C., K.CS. Pp. xiii. 667. (London : Longmans,
Green, and Co., 1894.)

THE author states in the preface, that the arrange-
ment of the course of elementary instruction in
chemistry, which is given in this book, is based on the
periodic classification of the elements. The properties
of four elements, hyiiroi^en, ii.ijxen, iiitnigen, and carbon,
and the properties of many compounds of these elements,
NO. 1307, VOL. 51]

are considered before the systematic study is entered on,
of the groups into which the elements are divided by the
application of the periodic law. Then follow chapters
wherein the members of the various groups of elements,
and the chief compounds of these elements, are described.
To this descriptive part of the book are prefixed fifteen
chapters of " introductory outlines," constituting " a brief
sketch of the fundamental principles and theories upon
which the science of modern chemistry is built." In his
directions to students using the book, the author says that
a start should be made by reading carefully the chapters
dealing with chemical change, elements and compounds,
nomenclature, and symbols ; that the four typical ele-
ments— hydrogen, oxygen, nitrogen, and carbon — should
thenbe studied ; and that, as this study is proceeding, the
remaining chapters of the "introductory outlines"
should be mastered.

It seems to me that the method of the author is
radically wrong. Descriptive statements of facts ought,
surely, neither to precede, nor to follow, but to accompany,
the reasoning on these facts whereby general principles
are gained.

The author's treatment of chemistry implies that " the
science of modern chemistry is built" on the foundation
of such generalisations as those stated in his " intro-
ductory outlines," and that detailed descriptions of the
properties of certain kinds of matter called elements
and compounds constitute the science that is raised on
this foundation. Would it not be more advisable so to
treat the subject as to show thit chemistry rests oncer-
lain definite natural facts, but that only when these facts
are compared, contrasted, and classified, does a scientific
knowledge of them begin ?

The descriptions in this book of the members of each
group of elements seem to me to be exceedingly well
done; many portionsof the chapters treating of principles
and theories, notably the pages which deal with the laws
of chemical combination, are admirable ; nevertheless
the book, as a whole, gives the impression of being un-
scientific. The method of the book tends, in my opinion,
to perpetuate the vicious and unreal distinction between
chemistry and chemical philosophy, a distinction that
has probably been as potent as any other cause in
stopping the progress of the science.

The purely descriptive portions of this work are often
extremely good, as far as they go. The facts, or rather
half-facts, are stated in a clear and orderly way ; care is
taken to notice recent work of importance ; the wood-
cuts are well executed : but, all this is only the material
out of which chemistry is constructed.

About 130 pages are devoted to statements of the pro-
perties of four typical elements— hydrogen, oxygen,
nitrogen, and carbon— and of the properties of many
compounds of these elements. But hydrogen, oxygen,
nitrogen, and carbon are not treated as typical elements
they are not compared and contrasted with other ele-
ments. After reading the descriptions of these elements
and their compounds, and studying the properties of the
elements in each of the eight groups of the periodic
classification, one still feels unsatisfied. Something is
lacking. Surely some fair and fitly fashioned building
ought to rise on this broad superstructure. If chemistry
IS to be treated as a recitation of disconnected, or artifi-

NoVtMBEK 15, 1894J

NA TUKE

53

cially connected, facts, it ceases to be a subject worthy
the serious attention of educated men. One turns to a
new book on elementary chemistry, hoping to find at
least an attempt to rescue chemistry from the overwhelm-
ing burden of so-called facts, beneath which the science
is in danger of being buried. In this case I confess to
disappointment. It may be replied that the chemistry
which is not clearly apparent in the purely descriptive
parts of the book is to be found in the " introductory out-
lines " wherein the " fundamental principles and theories "
of the science are stated. I admit at once that there is
much excellent matter in these earlier chapters ; but I do
not find there a connected setting forth of elementary prin-
ciples, as arising from facts, and binding facts into some
kind of harmonious whole. There is not much either
exact or imaginative treatment ; and these two I take to
be the notes of genuine science.

The perusal of this book produces in one's mind a
strange feeling of inversion ; many things seem to be
standing on their heads. The reader feels that a rapid
mental rotation, to right or left, is demanded. Change is
very properly said to be the feature of all chemical occur-
rences ; but at a very early stage (p. 5), after two pages
have been occupied in lightly touching the subject of the
constitution of matter, the student is told that " Any
change which arises from an alteration in the structure
of the molecule is a chemical change." This is an
example of the topsy-turviness of parts of the book.
The statement quoted has a meaning when the meaning
of such a very symbolical expression as " structure of the
molecule " has been adequately grasped. At this stage
of progress the student cannot have any clear image
called up in his mind by the words I have quoted ; they
must be merely words to him. But he might have
grasped the prominent and characteristic features of
chemical change had these been put before him by well-
chosen experiments. Another instance, to my thinking
a glaring instance, of putting theory where facts should
come, and facts where theory, is found in chapter ii.,
which deals with elements and compounds. The dis-
tinction between these classes of substances is stated at
once, and is stated only, in the language of atoms and
molecules.

" In the substance sulphur, all the atoms composing
the molecules are alike ; while in water . . . there are
two distinct kinds of atoms in the molecule. Matter,
therefore, is divided into two classes, according as to
whether its molecules are composed of similar or of dis-
similar atoms. Molecules consisting of atoms of the
same kind are termed eteiitciitary violecuUs, and sub-
stances whose molecules are so constituted are known as
elements."

The chapter which deals, and deals in a clear and
most praiseworthy style, with the laws of chemical com-
bination, is headed " The Atomic Theory." I think the
author must have taken his own words too literally
(p. 29) :

" Dalton embraced the ancient doctrine of atoms, and
extended it into the scientific theory which is to-day
known as Dalton's atomic theory, and is accepted as a
fundamental creed by modern chemists." (The italics
are mine.)

A " scientific theory " and a " fundamental creed " are
very different things.

NO. 1307, VOL. 5 l]

For his descriptive treatment of the materials from
which chemistry is built up, I think the author is to be
praised ; but I do not think he has succeeded in setting
forth the principles of the science of chemistry clearly,
adequately, or in fitting order.

M. M. Pattison Muir.

OUR BOOK SHELF.

Astronomia Sferica. An Elementary Treatise. By
Francesco Porro. (Roma : Societ.'i Editrice Dante

Alighieri, 1S94.)

In these 160 pages, the author has endeavoured with
success to bring before his readers, in as simple a way
as is consistent with the subject, the elements of spherical
astronomy. With the exception of a small knowledge of
the rudiments of the differential calculus, the mathe-
matical ability is by no means taxed. The order in which
the subject-matter has been arranged, and the field
which is covered, can be gathered from the following short

I summary. After dealing first with the sphere generally,
and the form and daily motion of the earth, the annual
motion round the sun, and the methods of the trans-
formation of coordinates, the measurement of time is
next explained, in which Kepler's equation, the equation
of time, and the transformation of mean into sidereal
time, and vice versa, are discussed. Then follows a
chapter in which the movements of the moon are clearly
expounded.

Diurnal parallax and refraction, the variations of the
fundamental planes, aberration and annual parallax, form
the subjects for the next three chapters ; while the re-
maining ones are devoted to the determination of the
positions of stars and their proper motion, and to the solar
system in general. In the last-named, the apparent
movements of the planets, the theories of Copernicus and
Kepler, the necessary data for the determination of
planets' orbits, &c., are touched upon.

From the above it will be seen that the most necessary
points for the student have been dealt with, but they
have not been treated at too great a length. As an in-

I troduction to higher works, this book will be found most
useful ; but its use in this country will be to a great
extent restricted, owing to it being printed in Italian.

The Nev Technical Educator. Vol. iv. (London, Paris,

and Melbourne : Cassell and Co., 1S94.)
The previous volumes of this work have been duly
noted in our pages. Volume iv. is in every way up to
their standard of excellence.

The subject of the manufacture of iron and steel
occupies the first part of the volume. The author of this
seems to be well acquainted with the practical details.
We note that he appears to consider that the presence
of but 005 per cent, of sulphur in steel is more or less
harmful, producing a metal sensibly red-short. This
may be the case ; but it is generally considered that the
percentages of phosphorus, sulphur, or silicon must
not each exceed 006 per cent., and then their efl'ects
may be overlooked in axles, tyres, plates, &c. Engine-
tyres are said to give a tensile test of 46 tons per square
inch, with a minimum elongation of 20 per cent, in a
3-inch length. These results are rather extreme, with a
sectional area of i square inch of test-piece. If the ex-
tension exceeds 16 per cent, the result maybe considered
good with this tonnage.

As in previous volumes, we find much interesting
information on cutting tools, from the pen of Prof. R. H.
Smith, dealing principally with lathes, drills, and punch-
ing and shearing machinery. Different metal shavings
are illustrated from photographs, and clearly show the
nature of the different metals. The steel shavings shown,

54

NATURE

[November 15, 1894

however, are not sufficiently described. Cases are known
•where shavings from a 2i-inch drill working on cast steel
have been obtained many feet in length, the material, of
course, being of very excellent quality.

The illustrations of drilling machines are good, but all
appear to have the ordinary power feed ; in many cases
it is found advantageous to have, besides the power feed,
a quick hand feed in addition, in conjunction with a
power attachment, the quick hand gear being used to
withdraw the tool in all cases. These motions are very
handy in boiler shops, where the same machine may
have to drill rivet-holes out of the solid, rhymer or
enlarge punched holes, and finally countersink holes, all
requiring different feeds.

The continuation of the steam engine in this volume
includes boiler fittings and details, efficiency of the engine
and engine and boiler trials, concluding with a chapter
on compound engines. The latter parts of these chapters
are well written and interesting. The classical work of
the late Mr. Willans is largely drawn upon, as well as the
trials carried out by the institution of Mechanical
Engineers, besides careful descriptions of other steam-
engine trials. The combination of indicator diagrams
of compound or triple expansion engines is wel
explained.

A series of articles on engineering workshop practice
is commenced, and they are very good so far as they go,
but it may be suggested that engineers' shop appliances
as generally used should be described, and not the
"elegant amateur tools," such as are illustrated in Figs.
29 and 77. J^- J- L.

Index Kcwensis Plaiitarum Phanerogamarum. Sump-
tibus Beati Caroli Roberti Darwin ductu et consilio
Josephi D. Hooker, confecit B. Daydon Jackson.
Fasciculus iii. (Oxoni : E prelo Clarendoniano, 1S94.)

The third fasciculus of the Kew Index, which the
Clarendon Press has just issued, brings us within sight of
the completion of this monumental work. This part
brings the Index down to near the end of the letter P,
and we may look forward then to seeing in course of the
coming year the concluding fasciculus. Since we noticed
the earlier fasciculi there has been no new development
in the nomenclature controversy, upon which, we believe,
the Kew Index will e-vercise an important influence ; the
effect of this will likely be only apparent after the whole
is published. Meanwhile the sterling value of the Index
is increasingly evident, and every botanist will congratu-
late the preparers and the publishers upon the appearance
of this third fasiculus, in which the same careful and
conscientious workmanship is noticeable as characterised
the portions of the work previously issued.

Alpine Climates for Comumplion. By H. J. Hardwicke,
.M.D. Pp. 65. (London: J. and A. Churchill, 1S94.)

THt high-aliitude cure for acquired and hereditary con-
sumption has gained ground in the medical world during
recent years, with the result that numerous winter health
stations have sprung into existence in Switzerland. Dr.
Hardwicke's little brochure has been written for the
purpose of providing trustworthy and unbiassed inform-
ation with regard to some of these resorts. It is pointed
out that the principal reqairemenls of an Alpine winter
-climate in the treatment of phthisis are (1) high altitude,
(2) low temperature, (3; dry atmosphere, (4) large amount
of sunshine and ozone, (5) low atmospheric pressure, (6)
freedom from wind, (7; freedom from organic and in-
organic panicles in the air, (8; absence of fogs, (9) good
water-supply, (10) good drainage. The author believes
that stations possessing all these properties are extremely
beneficial to consumptive patients. Mis book will help
sufferers from lung disease to the selection of a suitable
winter residence.

NO. 1307, VOL. 51]

LETTERS TO THE EDITOR.

The Editor dots not hold himsel/ responsible for opinions ex-
tressed by his correspondents. Neither can he undertake
to return, or to correspond with the writers oj, rejected
manuscripts intended for this or any other part o/Nature.
No notice is taken ot anonymous communications.^

" Acquired Characters."
It may be at once conceded that persons who discuss whether
" acquired characters " are inherited or not, ought to know and
to be able to stale clearly what is meant by the term "acquired
characters."

I am surprised that Sir Edward Fry should find any difficulty
in ascertaining what should be meant by this term when used in
the case to which he refers, viz. the theories of Lamarck and of
Darwin with regard to the origin of the species of plants and
animals. Sir Edward Fry seems to assume that the matter under
discussion is contained in certain writings by Prof. Weismann as
though ihose writings were a sort of "affidavit," binding and
limiting the discussion. The fact is that Prof. Weismann is a
wilnesi — and an advocate too — in a case which is of more
ancient dale than his connection with it.

Sir Edwaid Fry has found some satisfaction, as have many
other writers, in pointing out inconsistencies and ambiguities
in Prof. Weismann's statements ; but it is to me somewhat
astonishing that one should be invited to a textual criticism of
Weismann's words in order to ascertain the significance of the
term "acquired characters." The term and the discussion
about ihe inheritance or non-inheritance of acquired characters
were not invented by Weismann I They have been familiar
ever since the discussion of Mr. Darwin's book on the " Origin
, of Species," commenced thirty-five years ago. The term has
been explained and amplified over and over again. It really
dales back to Lamarck ; and 1 should propose, when anxious
to know ihe meaning of a lerm associated willi Lamarck's doc-
Irine, to invesligaie Lamarck's writings rather than Weismann's.
Lamarck's "Philosophic Z )ologique " was published in
1839. On p. 235 of vol. i. of the reprint of this work, issued
in 1S73 under the direction of Prof. Charles Martin, Lamarck
slates his two ' ' laws " of organic development. They run : —
Premiirc Loi. — " Dans tout animil qui n'a pjint depasse le
terme de ses developpements, I'emplol plus frcquenl et
soulenu d'un organe quelconque lortilie peu .1 peu cet
organe, le dcveloppe, I'agrandit, el lui donne une puissance
proporlionnc a la duree de eel emploi ; tandis qiie le dcfaut
constant d'usage de lei organe I'afiaiblit insensiblement, le
dcieriore, diminue progressivement ses faculies, el finii par le
(aire disparaiire."

Deiixiime l.oi. — " Tout ce que la nature a fail ,hi/u,'iir otx
perdre aux individus par rinlluence des circonstances oil leur
race se Irouve depuis longlemps exposce, el par consL\]uent,
par I'influence de I'eiuploi prcJominani de lei organe, ou
par celle d'un dcfaul constant d'usage de telle panic : elle le
conserve par la generalion aux nouveaux individus qui en
proviennent, pourvuque les changemenlsiiiY"" soient communs
aux deux sexes, ou a ceux qui ont produit ces nouveaux
individus."

I have italicised two words in this quotation. It is to this
doctrine of Lamarck that the short lerm "doctrine of acquired
characters" has been and is applied.

In the report of a lecture given by me, at the London
Institution, in February 1889 (published in N'ATURt of that
date), on " Dutwin versus Lamarck," the iwol.iws of Lamarck
were quoted in full. In lectures given some three years earlier
( I had pointed out that ihere is no satisfactory evidence that
I animals or plants transmit by generation the characters
I acquired by llie individual in the way su|>po>cd by Lamarck.
It is, I .admit, a very difficult matter 10 determine whether
a particular character which makes its appearance in the course
of the life of an organism has been "inherited" {i.e. is con-
genital) or " acquired." liul lliat has nothing to do with the
question as to what we should mean when we say "acquired
characters. " The answer to that seems to be ceitain and
simple. It is given by Lamarck, and the term directly refers
to Lamarck's doctrine.

(;n the oiher hand, it is the fact, as Sir Edward Fry points
out, that Wcisjiann and others have employed the term
"acqjired characters " in an extended and modified sense. To
this extension I will refer in another letter.

E. Kav La.nkester.

November 15, 1894]

NATURE

55

We must all agree with Sir Edward Fry's desire to obtain a
clear and exact definition of an "acquired character," as this term
has been used in the discussions upon hereditary transmissibility.
I do not think, however, that those who have taken part in the
various controversies and discussions which have raged inter-
mittently during the last seven years, have been misled by the
lack of asuthciently exact definition orthemultiplicity of inexact
ones. I believe that both sides have known well enough the kind
of character which was called acquired, even though no suffi-
ciently clear definition was forthcoming. And it may be that this
mutual understanding has tended to obscure the demand for a
definition.

An acquired character has generally been brielly defined as
"the result of the operation of some external force upon an
organism," and I still think that this is as satisfactory as any
definition of equal brevity can be. But some want of clearness
follows from the elasticity of the word "result." Everything
that follows the operation of some external force may be called
its "result"; but the definition interpreted in this way would
include much that is not within the meaning of the word
"acquired." Some increased precision may be added by using
the words "direct result"; but a perfectly satisfactory defini-
tion should, I think, imply the admission that the result (in its
wide sense) of an external force on an organism must always
contain elements which are not due to the force — which are not
acquired — as well a- those which are due to the force and which
are acquired. I think that the following definition will meet
the case; "Whenever an organism reacts under an external
force, that part of the reaction which is directly due to the force
is an acquired character. '

In many cases the external force acts only as a shock, with
the starling of reaction as its only direct result. In such a case
the occurrence of the reaction, as contrasted with the sequence
of events which make up the reaction itself, is the acquired
character. In examples such as these, those who maintain the
transmission of acquired characters would be required to prove
that the reaction which could only be started by an external
force in the parent, started without this stimulus in the off-
spring.

I believe the definition suggested above meets all Sir
Edward Fry's conditions — viz., that it includes all "acquired"
characters, and excludes all that are not acquired ; that it is
physical and not metaphysical ; that it is not "stated in terms
derived from hereditability or the contrary, or in terms of any
hypothesis or theory " ; and that it admits of ascertainment
and verification.

That a reaction under an external force is compounded of
two parts, due respectively to the body which reacts, and
to the force which causes the reaction, is a fact and
not a theory or hypothesis. It may be urged, however,
that the separation of the two constituents does not admit of
** ascertainment and verification." This may be true, in the
present state of our knowledge, for certain cases ; and if so, these
cases would be unsuitable for the purposes of an inquiry
into the transmissibility of acquired characters. But I do not
admit that it is proved that the two constituents of the reaction
cannot be separated in every case by a sufficiently careful
investigation. For the purposes of this inquiry it is sufficient,
however, if we can prove beyond doubt that some part of a
reaction is the direct result of an external force, even if we
have not thereby exhausted the whole of the direct results
contained in the reaction. For if this can be done in a vast
number of cases, an immense body of evidence will be provided,
and we may expect that, if acquired characters are traus-
missible, some proof will be forthcoming.

I propose to test the elficiency of the definition given above,
by showing how it can be applied to some of the examples given
in Sir Edward Fry's letter.

In the case of the "exercierknochen " it is clear that
the occurrence of the reaction — the existence of the bony
growth — is the direct result of the external force. Here then
is an acquired character which will be admitted by everyone,
which can be witnessed in a vast number of examples, and which
can be conveniently applied to test the transmissibility of such
characters. There may, or may not, be other direct results
contained in the reaction: some of I he processes of osseous
growth may have followed directly from continuous or inter-
mittent pressure. But in the first place the verification is much
more difficult, although not, I believe, beyond the reach of
scientific inciuiry, and, in the second place, such proof, if

NO. 1307, VOL. 51]

obtained, would yield evidence which would be far more
difficult to obtain. in very large quantity.

It is clear that when Prof. Weismann admits that " the
periodical change of leaf in temperate climates has been
produced in relation to the recurring alternation of summer and
winter," he is referring to the selection of inherent characters,
and not the production of acquired characters. The sentences
which follow the one quoted (p. 406), leave no doubt upon this
point. Sir Edward Fry may feel assured that when any direct
results of heat, cold, air, food, moisture, gravity, or light upon
the organism are proved to be heritable, the controversy is at an
end.

The case of geotropism logically resembles that of the
"exercierknochen." iThe occurrence of the reaction is
certainly a direct result of the external force — an acquired
character ; and here too we have an immense body of evidence
to which to appeal, and which points only in one direction. In
spite of the innumerable generations during which plants have
assumed certain relative proportions under the influence of
gravity, this influence is just as necessary to-day as it has ever
been, and the youngest generation starts unbiassed by the direct
result of external forces upon its ancestors.

As regards the "extra fingers or toes, patches of grey hair,
moles, cStc," the question is raised as to whether external forces
are not involved as direct causes. If this can be proved the
question at issue is settled, for such characters are known to be
transmissible. If not, the observation merely shows us that
certain characters, not proved to be acquired, are transmissible.
But if the non-transmi.ssibility of those proved to be acquired
has been established on a sufficiently large scale, then the
observation in question, accompanied by the continued absence
of proof that the characters in question are acquired, may be
fairly held to indicate the existence of two contrasted classes of
characters, which we may call spontaneous or inherent, and
acquired.

We are asked if we have any scientific knowledge of the
organic world independently of any external influence. This
method of eliciting an answer must not be allowed to disguise,
as it appears to do, the very positive knowledge we possess of
the separate effects of the several external influences. This is a
legitimate province of scientific investigation, and a large
amount of research at the present day is devoted to such
questions.

In handwriting the two constituents of the reaction are some-
what difficult, but by no means impossible, to distinguish. The
external influence of training operates upon the most complex
part of the organism, the nervous system, which again directs
the muscular system. Is the style of handwriting due to the
external force, or the organism which reacts? We can eliminate
pen, ink, and paper as influences by only considering the cases
in which these have been identical. There remains the influence
of the teacher, and in order to prove that this has been the
direct cause of style, it must be shown that the teacher had
produced the same style in many pupils. If a style so produced
became hereditary, evidence of transmissibility of an acquired
character would be provided. Conversely, variety of style
under the same conditions of teaching, &c., would favour the
view that we are not dealing with an acquired character in this
part of the reaction.

It is unnecessary to consider further the cases of mutilation
and wounds, for I imagine that Prof. Weismann, and all who
agree with him on this subject, will be willing to accept the
clear statements of Sir Edward Fry's letter. " What the
organism transmits is the capacity or predisposition, and not the
actual result ol the reaction." The latter in these cases is an
acquired chan^cter, while no one has ever shown that there is
any probability that the former is acquired.

I have, in this letter, avoided reference to many points raised
by Sir Edward Fry, not from want of interest or inclination, but
in order to keep to the main issue — the attempt to furnish a
clear definition of the class of characters in question.

If acquired characters are transmissible, we must expect that
sooner or later among the vast body of characters which are
or will be admitted on all hands to be acquired, some valid
instances of hereditary transmission will be furthcoming.

Such cases as that mentioned by Dr. Ilill in Nature of
October 25, when on a sufficient scale andadequately sifted, would
supply the requisite evidence. But up to the present such satis-
factory evidence has not been forthcoming, although it has been
sought for by many observers. Edward B. PoultoN.

Oxford, November 4,

5^

NATURE

[November 15, 1894

Thb rollowing seems a passable definition, such as Sir
Eiward Fry asks for in his letter of November 1. But, in
oSering it, I only speak of the sense in which I myself use llie
enpression.

Characters are said to be acquired, when they are regularly
found in tho>e individuals only, who have been subjected
to certain special and abnormal conditions.

Francis Galton.

Science Teaching in Schools.

Two articles have recently appeared in Nature which call
for some comment, if the columns of your journal are to be
opened once more to a discussion of this question. Educa-
tional ref irmers will agree heartily with the general position
taken up by Mr. H. G Wells, in "Science, in School and after
School" (vol. I. p. 525;, and by Prof. Armstrong in " Scientific
Method in Board Schools " (p. 631). But they either ignore or
give very little credit for the honest science teaching that is
actually being done at the present time. I realise, only too
personally, the great difference between training in scientific
method and mere instruction in science ; and how few are the
attempts to make use of the former in all grades of school.s.
But I hold that the old-fashioned instruction in science has,
under favourable conditions, a considerable ediualianal value.
To have enabled a boy to realise the composition of the air and
water is to have introduced him to the world of nature, and has
widened his ideas and conceptions to an extent which justifies
the means. Was not this one of the original pleas for the
introduction of science into the school course ? But having
entered my protest, I will pass on .

Mr. Wells admirably dis'inguishcs between the two styles of
science teaching, and points out the original function of the
Science and Art Department in encouraging and examining
only the one of them. But he admits that the field of operation
of the Department has been very much widened in recent years,
and that its examinations "seriously affect the teaching of
middle-class, and even of the higher standards of elementary
schools." Yet his only suggestion is that the Department
should withdraw from this work ; for that would be the efiect of
an age limit, and is intended to be the effect of the recent
alteration in the regulations in the elementary stage.

But circumstances are such that the Department cannot and
ought not to withdraw from its present control of science teach-
ing in day-schools, for its influence is greater than that of any
other examining body ; not simply financially, but from the
magnitude of its operations. It is a historical quibble to say
that the Department is concerned primarily with continuation
and adult cla-scs, when it specially encourages the formation of
organised science day-schools, and yet rigidly confines the
teaching in them to the schedules devised for adult instruction.

Last session there were 94 organised science day-schools, con-
taining about lo,OGO pupils taught on the lines la d down by the
Department. As is well known, the majority of these are what
are otherwise known as Higher Grade Board Schools, which
are absolutely dependent for their existence on the grants
obtained from the Department. I lake it as indisputable that
this is the very class of schools where the science ought to have
an educational basis; where its function is "to develop and
train the hand, eye and mind togclher, enlarge the scope of the
observation, and stimulate the development of the reasoning
power." I also believe that many of the teachers are anxious
to make it so, ju<lging from ihcir liberal denunciations of the
present "pernicious system." F. |ually axiomatic is it that,
under the Science and An Dep.irlmenl, it is impossible to
indulge in such leaching. Time will not permit. The pressure
ilio great that oxygen and water are almost always written and
(poken of as O and IIjO.

Mr. Wells considers other examining bodies, whose work is
exclusively directed to school needs, are far more blamewoithy.
This I absolutely deny. In the fir-t place, the South Kensing-
ton examinations are the only ones which arc entirely controlled
by scientific men. The sole cause for ihe existence of the
Department is Ihe encouragement of science and art, whereas
the other bodies referred 10 provide for the examination of
secondary education generally; and the examining board may
not have a single representative of science upon it. But
further, a-suming that Ihe .South Kensington examinations are
neither better nor worse than others, there arc two causes which
make them an educational abomination.

NO. 1307, VOL. 51]

(1) In one year the pupils have to be rushed through such an
excessive amount of work that the teaching degenerates into
the merest cram. The Department distinctly states that
students in the first year are to be prepared for the first stage,
and in the second year for the second stage. Putting aside
entirely the consideration as to whether the scheme is any par-
ticular subject, as chemistry, will any practical teacher deny
that the requirements for either the first or second stage are far
beyond what it is possible to accomplish with satisfaction
within the given time? It must be kept in mind that the
time-table has to provide not only for the seven or eight
subjects of which the Department takes cognisance, but ' ' for
instruction in those literary subjects which are essential for a
good general education." Do not these latter often suffer in
favour of the former, especially at the approach of May?

(2) The consequence of this restriction is that boys scarcely
in their teens enter by thousand- for an examination beyond
their normal capacities. It is in this that the South Kensington
examinations differ so entirely from those of the Universiiies.
The difference in standard between the Department's examina-
tion in chemistry and the Cambridge Junior Locals or London
.Matriculation is not great ; but in practice, the average age of
candidates in the latter is higher by two or three years. Time
is allowed for the awakening and development of ihe powers of
ob-ervation and reasoning. A boy is then able to describe
intelligently what he has become thoroughly familiar with,
instead of reproducing mechanically his notes or text-book.

In SI ill another particular have the University Boards a
decided advantage. Either they dispense altogether with an
examination in practical chemistry, or they make something
more of it than an analytical drill. Not much, it is ttue, but it
must be remembered that practical chemistry is the most per-
verted subject in the whole range of knowledge at the hands of
both teachers and examiners, liut the greatest mockery is that
which passes under the name at South Kensington. Of the
written part of the examination it is needless to say anything ;
no boy would regaid it as a test of what he has done in the
laboratory, but what he has seen in the lecture-room. As to
the analysis of salts, what bearing h.as it on the chemistry he is
being taught elsewhere? Though at a certain st.tge it has a
considerable educational value, tlie amount of lime wasted upon
it is appalling. It is useless to reiterate how easily it lends itself
to being converted into a mechanical grind.

Mr. Wells is of the opinion that the recent abolition of the
second class p.ass in the May examinations has had a beneficial
effect. So it may, in extinguishing what might be termed "bogus"
classes. But it has only intensified the evils in organised science
schools, and put a higher premium on the cleverest cramming.
The change did not deter such schools from sending in their
pupils as before, but now they h.id to obtain 60 per cent, of
the possible marks, or fail — and most of them failed. This year
ihere were fewer failures, because Ihe uaching has answered to
the whip. Financially the result is satisfactory to them, but
educationally it is disastrous. At that age the average boy is
not capable of obtaining more than forty or forty-five per cent,
of the marks in such a subject as chemistry. Very often he
does not understand the full meaning of the question ; and when
he does, he is unable to write down more than a moiety of what
he knows, or what could be drawn from him by a series of oral
<|uestions. There is no consideration shown for the immaturity
of the candidates, but the standard is pitched higher than that
of any other public examination in the country.

So far from agreeing with I'rof. Armstrong that science must
be admitted to equal rights wiihthe three A''<, I hold that it is
taught too extensively as long as the present system of examin-
ation prevails, and that the first battle to be fought ought lobe
against the South Kensington examinations, until they truly
perform Iheir double lunction. W. B. CkumI'.

Heath Grammar School, Halifax.

Will you allow me to take the opportunity allordeil by the pub-
lication, in NaTUKE, vol. I. p. 631, of Prof. Armstrong's address
at the Berners Street Board School, to offer my testimony to
the value of leaching, based on the piinciples which he advo-
cates so eloquently ? The fraclical difficulty of teaching what
I'rof. Armstrong has called scientific method in an ordinary
school, is ollcn ihe ground of the objection made to it, so that
it may interest your readers to hear of any experiments in this
direction.

November 15, 1^94]

NA TURE

57

My work has been amongst girls, and the attempts made thus
far in teaching scientific method in girls' schools show that such
a method will inevitably lead to the developmeut desired by
Prof. Armstrong.

Doubtless one of the drawbacks is the difficulty of giving to
each member of a large class the opportunity of individual work.
I am not sorry, however, to have sometimes laboured under
this difficulty myself, as it has brought about the discovery of
how much could still be done on the right lines. When neces-
sary I have replaced individual work by a demonstration class,
in which the pupils, th'ee or four at a time, have taken it in
turns to work in front of the others, the work consisting in the
solution of problems such as those suggested in the British
Association's report on chemical teaching. The principal results
are these : the children take a growing interest in the work,
and those who are doubtful how far girls may desire to work
with their hands, instead of always sitting still, may be glad to
hear that no greater incentive to invention can be given in a
demonstration class than the reward of becoming the experi-
menter for the time being. There is never any lack of
suggestion for the next step in the work, and the rapidity with
which such work trains the girls to consider the value or defects
of any new proposal for the solution of their problem, is some-
limes astonishing. In these classes the teacher plays a very
small part — at least, apparently — only from time to time direct-
ing the suggestions, and giving permission for new work to be
started ; invention, experiment, meaning of results, and criti-
cism are all undertaken by the children, and the final
" discovery " is their own triumph.

I have often been asked by teachers about the discipline of
such a class, since experimental work goes so slowly that they
think it would be impossible to keep those who are not actually
at work attentive. I can only say that the class consists of a
group of people genuinely interested in a common object, and
It behaves in the way such groups generally do. If at times a
girl's enthusiasm so far carries her away that she rushes from
her scat to the experimenting table, the class, with a laugh,
excuses her, sympathises with her feelings, and is not disturbed
thereby.

It seems unquestionable that the result of such work should
have a wider-reaching effect than the mere knowledge of certain
facts in nature, though such knowledge is also obtained.
Where children, through their own work, have been led to
observe and then to think, the result may fairly claim to be
truly educative, and one is often at a loss to understand what
support can be found for the still largely-existing method of
leaching not science but " useful information."

Another objection often made to teaching .scientific method
instead of facts, that it takes too much time, I have already
answered in this journal. I may perhaps be permitted to re-
peat that experiment shows the result of elementary training, of
the kind described, to have a lasting influence on the rapidity
and comprehension with which new subjects are grasped later
on. B ioks, too, which are never put into the hands of be-
ginners, are used with more than ordinary sense at this later
stage. I may say that, even from the examination test (which,
however, is not always going to be our standard), the results are
very favourable. One thing, however, cannot be done by the
teaching of scientific method, and that is to prepare for the
London Matriculation examination in chemistry in three
months — but then, is that altogether to be regretted ?

Grace Heath.

North London Collegiate School for Girls, November 5.

Italian Scientific Expedition to Monte Rosa.

In the summer of this year, my assistant Dr. L. Scofone and
I s ayed a month at the Alp of Lavez in the valley of
Gressoney, near the foot of the Indren glacier, at an altitude
of 2450 m., not far from the place where the brothers Schlagint-
weit spent some days in 1851 while engaged in their well-known
scientific observations on Monte Rosa.

We purposed to examine, both chemically and bacteriologically,
the composition of the waters of that region (inclusive of snow
and i:e) ; some of the analyses (ammonia, nitrites, nitrates
and organic matter) were imde directly on the spat, where we
had a small laboratory. To be able to carry the waters to
Turin, for further analysis, we had only to evaporate them, and
seal the residues in little glass bottles by means of a blow-
pipe. The detection of germs was made by using agar and

gelatine plates enclosed in the well-known Petri's glass-boxes ;
gelatine, agar, pipettes, and other instruments tieing duly
sterilised first in Turin, and then at Lavez, with a good hot air
oven. The development of germs was secured by putting the
plates in an incubating oven.

We also collected the water of the Indren torrentsissuing from
the glacier, and measured the amount of suspended matter in
the water, which can give an idea of the process of erosion that
takes place in the bed of the ice stream.

The results of the various observations will be published in
the scientific papers of Turin as soon as the study of the col-
lected material has been completed. It will perhaps interest your
readers to know that while the water of the springs, streams
and lakes was constantly free from ammonia, there was found
a tolerable quantity of it in the snow collected on the summit of
the Punta Guifetti or Signal Kuppe, one of the loftiest peaks in
the Monte Rosa range, measuring 4539 m. The ice of the
Lys Glacier, dug out from the depths of a huge crevasse, also
contained ammonia ; nitrites and nitrates being absent in every
case. Accordingly we found that the water of the Indren
stream, during a very hot day, when the melting of the ice was
considerable, contained traces of ammonia.

We also found that the ice and snow collected on the various
peaks, passes, and snow-fields of the Monte Rosa range, contained
a few germs. The number of the species whose germs can thrive
at those heights is certainly not large ; the usual forms, living in
decayed matter and ia the intestines, cannot probably endure the
condition of temperature, pressure and light of the place.

Turin, October 28. PlERO Giacosa.

Chinese Beliefs about Caves.

Mr. Herbert Spen'CER, in his " Principles of Sociology"
(3rd edition. New York, vol. i. p. 207), relates the beliefs in the
creation of mankind under the ground or in caverns, current
among the Todas in Asia, the Basutos in Africa, and at least
one-half of the .'.merican tribes. A similar belief I have lately
found in a Chinese record. In Li Shih's Siik I'oh-wuh-chl
(written in the 13th cent. A.D., Japanese edition, 1683, torn. ii.
p. 3) a quotation from the Ning-kwoh-lun runs as follows : —
" Primitively there was no Liau-Kien in Shuh (n )w Sze Chuen) ;
this tribe emanated from red clay in a cave of Teh-yang
mountain, whence bits of the soil had began to roll out,
each roll enlarging them, so that at last thereby was created a
couple, who gave birth to many."

In another paragraph Mr. Spencer remarks: — "Stationary
descendants of troglodytes think that they return into a
subterranean other-world whence they emerged {ibid.
p. 213). According to this, I would suggest that the same
belief, entertained by some aborigines in China, has revived
itself among the Taoists, who used to call their paradise the
" Cave-Heaven " (Tung- Tien) — e.g. Twan Ching-Shih describes
the " Cave-Heaven " 10,000 lis in circumference and 2600 lis
in height (his " -Miscellanies, " Japanese edition, 1697, tom. ii.
p. I), and Li Shih enumerates thirty-six caves in the empire, all
entitled ' ' Heavens " (ibid. tom. i, p. 8).

KUM.\GllSU Ml.NAKATA.

15 Blithfield Street, Kensington, W., November 2.

Spots over Dogs' Eyes.

I wot'Lii have written a note on this subject long ago, had I
not failed to see similar spots general amongst wild animals
allied to the dog. The spots may, however, be more general
than I am aware. The spots are by no means always tan ; a
black dog will sometimes have thei! white, and a white dc^
black. 1 have a whiteand tan fox-terrier, in which the spots
are very eye-like and jet black ; in a brown bull-pug of mine,
the spots are also black. These spots are so eye-like , that when
the dogs are asleep they seem at first sight to be wide awake.

Has not the human eyebrow, highly developed in some crude
races, as in Australians and Ainos, a similar meaning ? The
eyebrow gives many sleeping persons the appearance of being
awake. Worthing roN G. Smith.

Dunstable.

Gravitation.

In his interesting paper upon the "Mechanical Stretching
of Liquids" {Phil. Trans. 1892, A, p. 370), Prof. Worthington
describes a phenomenon of attraction bitweeu bodies immersed

N J. 1307, VOL. 51]

58

NATURE

[November 15, 1894

in a stretched liquid. His explanation is ingenious : that the
close contact of the bodies liberates from a denser surface layer,
liquid which will go to supply the prevailing demand, and so
lower the energy of the stretched liquid

Whether this be a quite correct explanation or not, does not
the experiment suggest the possibility of an analogous phen-
omenon occurring in a tensile ether in which matter is immersed ;
giving rise to the effects which we appreciate as gravitational
attraction? J. JoLY.

Trinity College, Dublin, November 6.

Homogeneity of Structure the Source of Crystal
Symmetry.

To the lucid notice of my paper, '■ Ueber die geometrischen
Eigenschaften homogener starrer Slrukturen und ihre
Anwendung auf Krystalle," contained in your issue of October
1 8, it is perhaps desirable to add a remark.

The paper referred to is purely geometrical ; it starts with a
de&nition, and not with a supposition. Consequently the various
new theories advanced by the writers referred to in the notice
receive no support Irom il.

Homogeneity of structure pure and simple, unaided by any
theory as to the nature of matter, leads inevitably to all the
varieties of symmetry presented by crystals. It is useless,
therefore, to look to the facts as to this symmetry for any light
upon the vexed question whether the seat of the symmetry is in
the arrangement or in the configuration of the molecules, or,
indeed, for any proof of the existence of molecules or separable
units. \Vm. 1!.\rlow.

Muswell Hill.

THE PRESENT STATE OF PHYSIOLOGICAL
RESEARCH.

THE following extracts from an article by Prof. Max
Verworn, of Jena, on " Modern Physiology," pub-
lished in the Moni'st for April 1894, seem to be well
worth the attention of English biologists. It would be
interesting to obtain in the pages of X.\tlre an ex-
pression of opinion from our physiologists as to how far
the reproach is true, that "in treading the beaten paths
we are making no progress in physiology, and have stood
still for years on the same spot." How far is it true that
physiologists must revert to the point of view of com-
parative physiology, or the physiology of the endless
variety of lower and simpler forms of life which was that
which formerly so fruitfully shaped the research of the
great master Johannes Muller? Is it, or is it not, time that
the methods of horological physiology were less dominant
and gave place to a determined and persistent study of
living structure in many of its varied manifestations
other than the frog and the rabbit ?

" Psychologically, it is a highly interesting phenomenon, and
one of moment in the history of science, that now, almost
immediately after the final suppression of the old vitalism by
the new development of the natural sciences, we have again
arrived at a point which corresponds in the minutest details to
the reversion lo mystical viialism which took place after the
clear and successful research of the preceding century. As a
fact, the parallel between the conditions of the eighteenth
century and those of to-day is unmistakable. Now, as then,
the physico-chemical method of explaining phenomena of life
looks back on a brilliant, almost dazzling sequence of successes ;
now, as then, the tracing of vital processes to physical and
chemical laws has re.'<chcd a point at which, for many years,
with the methods now at our command, no essential progress
has been made, where, on the paths hitherto trodden, a
boundary line is everywhere distinctly marked ; and now, as
then, on the horizon of science the ghusi of a vital force looms
up. It has already t.ikcn posses-ion of the minds of serious
thinkers in Germ.iny, with the dire prospect of more extensive
conquests ; and in I- ranee, too, it would seem, science is slowly
opening its door to this invasion of genuine mysticism.

"To underpitand this phenomenon psychologically, and to
acquaint ourselves with the means lA slaving off a general
reaction into vitalism, it ii desirable to examine more carefully

NO 1307. VOL. 51]

the present state of physiology. A review of the productions
which appear in our different physiological journals, which will
best exhibit the present state and tendency of the science,
furnishes an extremely remarkable spectacle. Leaving aside
the science of physiological chemistr)', which is independently
developing with great success, we find, with the exception of a
few good contributions to the physiology of the central nervous
system, as a rule, only extremely special performances of very
limited scope and import, wholly without significance for the
greater problems of physiology, whether practical or theoretical,
and exhibiting no connection whatever with any well-delined
general problem of physiology. In fact, what is called physio-
logy is beginning here and there to degenerate into mere tech-
nical child's play. With every new number of our physiological
magazines, the unprejudiced observer is gradually gaining the
conviction that general problems of physiology no longer exist,
but that inquirers, driven to desperation in the struggle for
material, have no choice but to hunt up the old dry bones of
science, on which they fall with the nervous rapacity of hungry
dogs. And in the case of most of the productions, this im-
pression is strengthened by the fact that the results, when once
found, are wholly disproportionate to the tremendous expendi-
ture of labour and time which it might be seen beforehand they
would require. .\nd yet all the lime the great problems of
physiology everywhere stare us in the face and seek solution.
For. if we regard the problem of physiology as the investig.ition
of the phenomena of life, we are certainly yet very far from the
solution of even its most important and most general problems.
We need not go to the extreme that Bunge does in his excellent
text-book of physiological chemistry, of maintaining that the
phenomena of our organism which we have explained mechani-
cally are not genuine vital processes at all, no more than is
' the motion of the leaves and branches of a tree shaken by a
storm, or the motion of the pollen which the wind wafts from
the male to ihe female poplar.' Hut it is certainly no ex-
aggeration to say that what the splendidly-conceived methods
of the gre.it masters of physiology since Johannes Midler havc
explained, are not elementary processes of life, but almns:
exclusively the crude physical and chemical actions of llic
human body.

"For what have we attained? We have measured and
registered the motions of respiration, the mechanics of the
gaseous exchange in the lungs in their minutest details. We
know the motions of the heart, the circulation of the blood in
the vascular system, nay, even the slightest variations of Ihe
pressure of the blood, as produced by the most diverse causes,
as accurately as we do the phenomena of hydrodynamics in
physics. We know ihat respiration and the motion of the heart
are conditioned by the automatic activity of nervous centres in
the brain, but no spirometer, no kymogrnph, no measuring or
registering apparatus can give us the slightest idea of whal
takes place in Ihe nerve-cells of the brain that condition the
healing of the heart and respiration.

'■ Further, we have investigated the motions of the muscles,
their dependence on the most diverse factors, their mechanical
powers, their production of heat and electricity, as exhaustively
as only the phenomena of the special departments of mechanical
physics have hitherto been treated. Uut of wliat goes forward
in the minute muscle-cells during simple muscular contraction,
no myograph, no galvanometer has as yet given us the slightest
hint.

" We know also the laws of the excitability of Ihe nervous
fibres, of the propagation of irritations, of the direction and
velocity of nervous transmission, thanks to ihe ingenious
methods of recent physiology, in all their details. Hut of what
is enacted during these processes in the nerve-libres and in the
ganglion-cell from which it ramifies, no induction-apparatus or
muliiplicalor can give us the least information.

" We know beMdes, that the heal and electricity produced by
the body, and ihc mechanical energy of mu-cular work, are the
consequence of Ihe transformation of the chemical energy which
we have taken into our bodies with our food. Hut by means
of what chemical processes the cells of the individual structures
take part in these achievements, the most sensitive thermo-
meter or calorimeter will not disclose, and no thermal pile or
graphical apparatus will indicate.

" We might give any number of examples of this kind, but
those adduced exhibit distinctly enough the point lo be sigua-
lised. What we have hitherto attained is this; we have
measured, weighed, described, and rcgisleied the gross

November 15, 1S94J

NA TURE

59

•mechanical actions of the human body, for the most part with a
degree of precision that would excite the astonishment of the
uninitiated ; we have also acquired a considerable knowledge
of the rough mechanical interactions of the individual organs of
the body, the mode of operation, so to speak, of the machinery
of organisms. But all that has been done, has been done only
up to a certain point ; and this point, at which we are brought
to a halt, is the cell. We have traced all phenomena of change in
matter, form, and force back to the point where they disappear
in the cell. But of what takes place in the muscle-cell, the
ganglion-cell, the lymph-cell, the gland-cell, the egg-cell, the
sense-cell, and so forth, we have not the slightest conception.
Moreover, we discover here, that even the minutest cell exhibits
all the elementary phenomena of life ; that it breathes and takes
nourishment ; that it grows and propagates itself ; that it moves
and reacts against stimuli. The elemen taiy riddles of life,
accordingly, have so far defied all research.

" A balance thus cast of the results of past physiological
research does not, it must be admitted, exhibit a very
encouraging outlook.

" But the resignation of physiology has been strengthened by
anothci prominent factor. This is the attitude of physiological
research to psychical phenomena. This attitude is at the present
moment a varying one. On the one hand, we still find secretly
cherished the vain hope of a chemical and physical explanatiou
of psychical processes, that is to say, of a reduction of them to
the motions of atoms, even though Du Bois-Reymond, in his
famous address on ' The Limits of Our Knowledge of
T\ature,' ' characterised such an understanding as utterly futile ;
while on the other hand we meet with an absolute resignation
in the face of this question — an attitude which is simply
a frank acceptation of the conclusion of Du Bois-Rey-
mond's, address. Owing to the authority of its author, the
' Ignorabimus ' of Du Bois-Reymond has influenced great
numbers of inquirers, and produced in physiology a real
paralysis of research, so that the abandonment thus effected
of the solution of the old problem of explaining psychical
phenomena mechanically has caused physiology for the most
part anxiously and reverently to avoid any intrusion whatever
■of psychological questions. On the one side, then, is the idle
hope of solving a problem which, despite its being as old as
human thought itself, research has not yet even touched ; and
on the other, an absolute renunciation of any treatment of the
problem whatsoever.

Cellular Physiology.

"If on the one hand we can Ijustly cherish the hope that the
increasing extension of the monistic world-view in natural
science will ward off the dangers of a reaction to the old
•viialism, the fact neveitheless remains that in treading the
beaten paths we are making no progres whatever in physio-
logy, and that we have stood still for years on the same spot,
and not approached a single step nearer our goal of explaining
the elementary phenomena of life.

" We have reached a turning-point in physiological research
which could scarcely be made more prominent. The reappear-
-ance of vital force is a token of it. As before all great crises
of history portentous spirits appear to clairvoyant people, so in
our days the ghost of the old vital force has loomed up in the
fiiinds of some of our natuial inquirers.

" But striking and obvious as the fact is that we can no longer
approach by the old paths of research an explanation of the
-elementary phenomtna of life, still, it is exactly as obvious anil
striking in what direction there is the only chance or hope of
our approaching our goal.

" \Ve have traced the vital processes of man in physiology
back to the point where they aie lost in the cell. Now, what
is more reasonable than that we >hould seek them out in the
<:ell ? In the muscle-cell is hidden the riddle of -muscle-move-
ment, in the lymph-cell is hidden the causes of secretion, in
the epithelial cell is buried the problem of resorption, and so
■on. The theory of the cell has long since disclosed that the
cell is the elementary foundation-stone of the living body, the
■"elementary organism' itself, that in which the processes of
life have their seal ; anatomy anil evolution, zoology and
botany, have long since realised the significance of this fact,
and the wonderful development of these sciences has furnished a
brilliant proof of the fruiifulnessof this branch of inquiry. Only

^ Veber die Grcnzcn dcs ^'atiircrkenncns. Rcdtn. Erste Folgc.
Leipsic, 1886.

NO. 1307, VOL. 51]

in physiology was the simple, obvious, and logical consequence
overlooked, and until very recently not practically applied, that
if physiology regards it at all as her task to inquire into the
phenomena of life, she must seek these phenomena at the spot
where they have their origin, at the focus of life-processes, in
the cell. If physiology, therefore, is not simply content with
confirming the knowledge which is already gained of the crude
mechanical actions of the human body, but makes it its object
to explain clearly elementary and general phenomena of life, it
can accomplish this object only as cellular physiology.

" It may appear paradoxical, that although nearly half a
century has elapsed since Rudolf Virchow first enunciated in
several classical works the cellular principle as a basis of all
organic inquiry, a basis on which to-day, indeed, all our ideas
in pathology are constructed, physiology still is only just begin-
ning to develop out of a physiology of organs into a physiology
of cells. Vet this is the true and normal course of development
of science which always advances from the crude to the delicate.
And it would therefore be impardonable ingratitude, and a mis-
taking of the mode of development of human knowledge, if we
should seek in the least to underrate the high importance of the
physiological research of the past epoch, on whose shoulders in
fact we stand, and with whose results we more or less con-
sciously continue our work. Further, in our judgment of the
course of development of physiological research, a factor must
not be overlooked which controls the development of every
science, namely the psychological factor of fashion. The de-
velopment of every science depends on the stupendous influence
of great discoveries. Wherever we cast our eye in the history
of inquiry, we find that great discoveries such as, to take the
case of physiology, are represented in the works of Ludwig,
Claude Bernard, Du Bois-Reymond, and Liebig, deflect interest
from other fields and induce a great multitude of inquirers to
pursue research in 'the same direction, with the same methods,
especially when these methods have proved themselves so
wonderfully fruitful as in the cases adduced. Thus, certain
departments of inquiry become, in connection with epoch-
making performances, fashionable, and the interest of thinkers
in others subsides. But an equalisation in the course of time is
always re-effected, for every field of inquiry, every method of
inquiry is finite and exhausts itself in time. We have now
reached just such a point in physiology : the physiology of organs
is in its period of exhaustion. Also the method of cellular
physiology will exhaust itself in the course of time, and its place
will be taken by other methods which the present state of
the problem do not yet require.

But for the present the future belongs to cellular physiology.
There are, it is true, inquirers who, although they are convinced
of the present necessity of a cellulur physiology, and see
perfectly well that the cell as the focus of the processes of life
must now constitute the real object of research, yet doubt for
technical reasons whether it is possible to get at the riddles of
life as they exist in the cell. It may, therefore, be justly demanded
that some way, some methods be shown with which a
cellular physiology can be founded. The doubt of the feasibility
of this undertaking is in great part the outcome of a phenomenon,
which, unfortunately we must say, has characterised physiology
ever since the death of Johannes Miiller, namely, the total lack
of a comparative physiology. Physiology has not yet entered
on this rich inheritance ol the great master. How many among
the physiologists o( the day are acquainted with other objects of
experiment than the dog, the rabbit, the guinea-pig, the frog,
and a few other higher animals ! To how many are the
numeiuus and beautiful objects of experiment known which the
wonderful luxuriance of the lower animal world offers ! And
yet, just among these objects are to be found the forms which are
best adapted to a cellular-physiological solution of physiological
problems.

"Naturally, if we believe we are limited, in our cellular-
physiological treatment of the riddles of motion, digestion,
and resorption, solely to man and the higher animals, we
shall encounter in our investigation of the living muscle-
cell, lymph-cell, epithelial cell, and so forth, more or less in-
superable technical difficulties. And yet the splendid researches
of Heidenhain on secretion, digestion, lymph formation, and
so forth, have shown what good results the cellular-physio-
logical method can achieve even here. Well-planned his-
tological experiments, such as those which put the living
cell in its intact connection with the remaining woof of the
body under given conditions, and then investigate the results

6o

NATURE

[November 15, 1894

in the suddenly slaughtered animal, to get from such experi-
ments light on the processes peculiar to the condition of life,
undoubtedly furnish the germ of much valuable knowledge.
But it is of the very nature of these experiments that they must
always remain difficult and restricted, for the living object, the
tissue-cell, is accessible to microscopic investigation only with
the greatest difficulty. Comparatively small difficulties in this
respect are offered only by the free-living cells of the organism,
as, for example, by the leucocytes or blood-corpuscles. And as
a fact, by the researches of MetschnikofT, Massart, Buchner,
Gabritchevsky, and many others, we have recently acquired
some important and wide-reaching expsrimental knowledge
concerning the vital phenomena of these very objects.

" But if we place ourselves at the point of view of comparative
physiology which Johannes Muller represented throughout his
whole life with such success and energy, an intinitely broad
perspective opens itself up for cellular investigations. A com-
parative view shows one fact of fundamental importance,
namely, that elementary life-phenomena are inherent in every
cell, whether it be a cell from the tissues of higher animals or
from the tis-sues of lower animals, whether it be a cell of a
plant, or, lastly, a free cell, an independent unicellular
organism. Every one of these cells shows the general
phenomena of life, as they lie at the basis of all life, in their
individual form. With this knowledge, all that it is necessary
for the inquirer to do is to select for every special object of ex-
periment the fittest objects from the wealth of forms presented,
and with a little knowledge of the animal and plant world, such
forms really obtrude themselves on the attention of the experi-
menter. Accordingly, it is no longer necessary to cleave so
timorously to the tissue-cells of the higher vertebrate animals,
which, while alive and in normal environment, we can only use
for microscopic experiments in the rarest and most exceptional
cases ; which further, the moment they are isolated from their
tissues, are no longer in normal conditions, and quickly die or
give reactions that may easily lead to wrong conclusions and to
enocs. Much more favourable are the tissue-cells of many in-
vertebrate, cold-blooded animals or plants which can be more
easily investigated in approximately normal conditions of life ;
yet even these, as a rule, will not outlast protracted experi-
ments. But here appear as the fittest imaginable objects, for
cellular-physiological purposes, free-living unicellular organisms
— namely, protists. They seem to be created by nature ex-
pressly for the physiologist, for they possess, besides great
powers of resistance, the incalculable advantage of existing in
a limitless variety of form, and of exhibiting, as the lowest
organisms that exist, all phenomena of life in their simplest
conditions, such as are not to be found among cells which are
united to form tissues, on account of their one-sided adaptation
to the common life of the cellular colony.

"Concerning the application of experimental physiological
methods to the cell, wc need be in no perplexity as :o which
we shall choose. In tlic luxuriant multiplicity of form which
this world presents, there can always be found for every pur-
pose a great number of suitable objects to which the most
different special methods can be capitally applied.

" Wc can, to begin with the simplest method, apply in the
easiest manner imaginable to the free-living cell the method of
simple microscopic observation of vital processes. In this
manner mere observation has furnished us knowledge of the
individual life-phenomena of cells in many details, and also of
their mutual connection. Among the most recent achieve-
ments of this simple method may be mentioned only the ex-
tremely valuable knowledge concerning the more delicate and
extremely minute circumstances of fecundation and propagation
which Flemming, Van Beneden, the- llertwigs, Strasburger,
Boveri, and many others have gained in recent years, partly
from living cells and partly from cells fixed in definite
conditions of life.

" Moreover, we can also conduct under the microscope vivi-
lectional operations on unicellular organisms in exactly the
same scope and with greater methodical precision than can be
done on the higher animaU. .Several inquirers, as Gruber,
Balhiani, and Hofer, have alrer\dy trodden Ihii path with great
•access, and a considerable group of researches has shown dis-
tinctly enough the ftuitfulncss which this cellular vivisectional
method of operation promises for the treatment of general
physiological problems. With this vivisectional method also
Koux, the llertwigs, and others conducted their splendid in-
vestigations on the ' mechanics of anitiiil evolution,' by showing

what functions in the development of animals fall to the lot of
the different parts of the egg-cell, or to the first filial [cells that
proceed from their division. • ■ •

" We can also apply here, in its whole extent, that powerful
physiological method known as the method of irritation, and
investigate the effects of different kinds of irritation on the life-
phenomena of the cell or of dift'eient cell-forms. The vegetable
physiologists have already collected a great mass of material in
this field. But also in the department of animal physiology a
great number of recent works have endeavoured to prove that
the phenomenon of irritation which takes place on the applica-
tion of chemical mechanical, thermal, galvanic, and luminous
stimuli to unicellular organisms are of the greatest importance
for the phenomena of life generally.

'■ Finally, we can approach the life-phenomena of the cell
chemically, although in this direction only the very first begin-
nings have been made, seeing that the microchemical methods
have been hitherto little developed. Nevertheless, the labours
of Miescher, Kossel, .Vltmann, Zacharias, Liiwit', and others
have already shown that the microchemical investis;ation of the
cell has a future of great promise."

INK-CRYSTALS.

THE pictorial representations of the forms taken by
ice-crystals are familiar to everyone ; and many
young observers have been grievously disappointed with
the difference between nature's handiwork and artistic
fancy, as exemplified by the ice-crystals really seen and
those which embellish scientific works. These " ice-

NO. 1307, VOL. 51]

Fig, I, — C'ystals form:d !)>■ the Ev.iporaiion of Ink.

flowers," as Tyndall called them, cannot always be con-
veniently produced, so a substitute for them, in the form
of " ink-tlowers," should be interesting to students of
crystallography. Dr. K. Troucssart describes in La
Nature how " fleurs de I'encre " can be procured, and
the accompanying illustration reproduces some of the
forms observed by him. The method employed is very
simple. A drop of ink is allowed to dry on a slip of
gliss, and observed under a microscope with powers of

November 15, 1S94]

NA TURE

61

50, 100, or 200 diameters. The inks of commerce vary
somewhat in composition, hence the facihty with which
certain crystalline forms are obtained difters. All inks,
however, having a base of solution of gall-nuts and sul-
phate of iron, give analogous results.

Dr. Trouessart hesitates to express an opinion as to
the nature of the salt which crystallises in the forms
illustrated. The crystals chiefly belong to the cubical
system, and this suggests that they are magnetic oxide
of iron. On the other hand, their white colour, and the
peculiar shapes of some of the groups of crystals, indicate
that iron disulphide or marcasite is the substance in ques-
tion. Perhaps some worker in chemical crystallography
will determine the point.

NOTES.

We learn from the Lancet that the late Prof. Pouchet, of the
Museum d'Histoire Naturelle, has bequeathed his entire fortune
to the Paris Society of Biology. The bequest is made in the
following terms: "N'ayant pas de famille, je legue tout ce
que je possede a la Societe de Biologie, oil j'ai toujour^ trouve
bon accueil et sympathie depuis le jour oii j'en ai ele membre.
Je crois fermement que c'est le meilleur usage social a faire du
peu de bien que je laisse environ 2000 francs de rente." (^80
a year).

Dr. Walter Dickson, R.N., the author of "The Ant-
arctic Voyage of H.M.S. Pa^oJa," and several works on naval
hygiene, died on the 9th inst. at the age of seventy-three.

By the recent death of Lieut. -Colonel Garrick Mallery, in his
sixty-fourth year, the U. S. Bureau of Ethnology has lost one of
its chief ornaments. The results of his important researches into
the sign and gesture language of American aborigines occur in
the current annual report of the Bureau.

The Times reports a severe earthquake and volcanic eruption
at Ambrym, an island in the New Hebrides group. The dis-
turbance is said to have occurred on October 15, when several
severe shocks were felt throughout the whole island. Immedi-
ately afterwards the volcano, which is 2500 feet high, was
observed to be in active eruption. The lava destroyed the
native villages on one side of the island, and a large number of
natives sought refuge on board H.M.S. Dart, which was
cruising off the coast. Considerable damage appears to have
been done in a large portion of the island.

The Christmas course of lectures, adapted to children, at the
Royal Institution, will be delivered by Prof. J. A. Fleming,
F.R. S. The subject will be "The Work of an Electric
Current," and the first lecture will be delivered on Thursday,
December 27, at three o'clock.

For several weeks the weather over the British Isles has been
very unsettled, but no gales of serious importance had been
generally experienced until Sunday night, when a deep baro-
metric depression reached our south-west coasts from the Atlantic,
accompanied with very heavy rainfall in the south and west ;
'he amount measured at Scilly during twenty-four hours ending
8 a.m. on the 12th instant amounted to over three inches, or
nearly the average fall for the month, while at Hurst Castle, on
the Hampshire coast, the fall exceeded two inches. The central
area of the storm passed the whole length of the English
Channel, and crossed the North Sea during Monday night,
Strong northerly gales being experienced in the rear of the dis-
turbance, accompanied with thunderstorms, hail, and more
NO. 1307, VOL. 5 l]

heavy rain, the amount measured in London on the 13th
instant being about 075 inch. A very rough sea was experienced
in the English Channel and in the Irish Sea. This disturbance
was followed by another which approached our extreme north-west
coasts on Tuesday night, causing strong gales overall parts of the
country, and very heavy rain in the west. The temperature
has been from 4° to 6" above the mean ; during the week ended
the nth instant the highest maxima recorded were 61° in the
Channel Islands, and 60° in the south of England, and the
lowest minima fell to 29° in the south-west of England, and to
32° in the Midland Counties.

Prof. Guido Cora, of Turin, will, on his approaching
birthday, December 20, be presented by his former students
with "a special mark of esteem and affection" in the form of a
memorial in recognition of the twenty-fifth anniversary of his
first published paper. It is well known that he founded and has
maintained the geographical Journal, Cosmos, at his own expense.
In order to give his many scientific friends an opportunity of
sharing in the general recognition of Prof. Cora's labours, Prof.
Paul Revelli, 12 Via Galliari, Turin, is prepared to receive any
written "sentiment," portrait, drawing, or signature for the
memorial volume. The date up to which such tokens of respect
may be sent is extended to March 31, 1895.

Dr. Do.naldson Smith, who left London early this summer
to attempt to reach Lake Rudolf from the north-east, has been
able to send letters home from a position in 7° 11' N., and
42° n' E., dated early in September. He hid formed a
caravan at Berbera, started with more than a .hundred
camels, and travelled south-westward through an unmapped
country, of which lie has made a running survey. At Turfa he
reached a great river, which he believes to be the Erer, and to
be continuous with the Webi Shebell. Being unable to cross,
he spent a week in following the course of this river, thirty miles
of which he has mapped ; and on his return he succeeded in
finding a ford, where the caravan crossed with much difiiculty.
The country was very thinly peopled, on account of wars between
the Gallas and Ogadams, but some natives were found to carry
letters to the coast, a task which they must have performed very
expeditiously. Dr. Smith has made large collections of the
fauna and flora of the region traversed, and has had some thrill-
ing adventures with big game. His men were doing well, and
he was confident of success in his journey, although the time
necessary to complete it appeared likely to be rather longer
than was originally expected.

The death is announced of Colonel R. \'. .Vrmstrong, C.B.,
F.R.S., late of the Royal Engineers. He was born in 1839,
and was the son of the late Rev. W. Armstrong, of Cairy,
County Sligo.

In the last number of the Scottish Geographical Magazine
Mr. W. S. Anderson, of the Scottish Marine Station, discusses
the relative merits of the methods for determining the density o f
sea-water by means of hydrometers and by direct weighing. He
shows that if the temperatures of water, instrument, and air are in
equilibrium, and the observations made on land, the Chalicnger-
type hydrometer yields results of equal value with those of
Sprengel tubes, provided the mean of a large number of ob-
servations is taken. At sea the hydrometer is less satisfactory.
Mr. Anderson throws discredit on previous work in this
direction, and assumes that the work of some earlier observers
showed large discrepancies on account of the scale of the
hydrometer being read from the wrong end. Unfortunately, he
does not make any reference to the place where this work is
published. By the use of a very large hydrometer admitting of

62

NA TURE

[November 15, 1894

he detection of extremely delicate differences in density, Mr.
Anderson satisfied himself that capillarity has no perceptible effect
upon the accuracy of the readings. By a series of observations
at different temperatures he has been able to construct new tables
for the reduction of observed densities to standard temperature,
and for the calculation of the function D, which is the difference
of density between the sample and pure water divided by the
number of grammes of chlorine per litre, a function to which
considerable importance is now attached in the discussion of the
relative differences between samples of sea-water.

Our excellent contemporary, The Engineering Magazine,
commenced a "Review of the Industrial Press" in the October
number, andanindexof current technical literature. The object
of this review and index is to give concisely-written notices of the
most important articles of the month ; and to supply a carefully
classified index to all the articles published currently in the
scientific and industrial press of the United States and Great
Britain. An entirely new feature is the establishment of a
department to supply all or any portion of any article reviewed
or indexed. That technical journalism has grown to pro-
portions and importance which warrant such a development, is
a fact at which we can all rejoice.

Observations on the variations in level of well-water have
been made for the last three years at the Observatory of Catania
in Sicily, and the first results are described in a paper by
A. Ricci) and S. Arcidiacono (Boll. mens, delf Ace. Cioenia di
Sei. Nat. in Catania, fasc. 37, June 10, 1894.) They classify
the movements into progressive, annual and accidental, sub-
dividing the la'.ter into meteoric and geodynamic. The
accidental variations of geodynamic origin consist of small
abrupt changes of level, generally downwards, which frequently
correspond to movements of the ground. Shortly before the
eruption of Etna in 1892, and for several months after, the
changes in level of the water-surface were extremely irregular.
From June I, to December 31, 1892, corresponding to]thirly-nine
groups of earthquakes, there were abrupt changes of level within
twenty-four hours in twenty-one cases ; there were also fifty small
but marked changes coinciding with strong oscillations of the
tromometer. Somewhat similar observations have been made
in Wisconsin, by Prof. F. H. King (U. S. Dep. of Agri.
Weather Bureau, Bull. No. 5). Here the shock was imparted
by heavily-laden trains passing less than fifty yards from the
well ; but the surface of the water invariably rose, sometimes
as much as one tenth of an inch, returning to its former level
after a few seconds.

At a recent meeting of the Academy of Science of Amstec-
dam, Herr C. H. Wind read a note on the Kerr phenomenon.
Th;: author breaks up the clsclric current into two parts — a
current of conduction and a displacement current — and to these
attributes, as Lorentz has done, the Hall effect. He supposes,
however, that the electromotive force which constitutes the Hall
effect is different for the two constituents, while Lorentz sup-
poses them to be equal. The introduction of this hypothesis
into the calculations of Van Loghem does not alter the general
form of the results, but has the effect of giving expressions for
the phase and the amplitude of the magncto-op'.ic component
which differ by a constant quantity and a constant angle from
the old values. In this way the difference of phase discovered
by S.ssingh it explained ; and from the observed value of this
difference of phase the ratio Iwtween the intensity of the Hall
effect for the displacement and conduction currents can be cal-
cula'ed, and then from observations of the amplitude the value
of each of these can be found. From the calculations made
by the author, it appears that the values thus obtained are of
NO. 1307. VOL. 51]

the same order as those got by direct observation of the Hall
effect, if we suppose that the specific resistance of metals for
periodic currents of extreme rapidity is greater than for con-
tinuous currents. This view is further supported by other cal-
culations which have been made by the author. The paper
concludes with a comparison between the above theory and the
theories propounded by Thomson, Goldhammer, and Drude,

I.N" No. 38 of the Silztingshriihte of the Berlin .\cademy,
Prof. Goldstein gives an account of a curious effect which the
cathode rays exert on the colour of certain salts. If potassium
chloride be made to phosphoresce in a radiation-tube, it quickly
assumes a strong heliotrope shade, and eventually becomes
bright violet. On heating, the colour changes to blue, and at
high temperatures the salt becomes white. The same series of
colour-changes may be obtained with this decolourised salt,
and also with naturally occurring pot-issium chloride or sylvine.
Several haloid salts of the alkali metals were examined, and
with the exception of c.^ciium and rubidium chlorides all gave
after-colours. The chlorides of barium and strontium gave no
after-colours. In ordinary air the colour disappears the more
quickly the more soluble the salt. The colour of lithium
chloride fades almost immediately ; the blue colour of sodium
chloride lasts about a day. In contact with water the salts at
once lose their colour. In a vacuum or in dry air the deep blue
colour of lithium chloride has now lasted for two months with-
out apparent change. The colour of potassium chloride
gradually fades and completely disappears in ,-ibout a week ; the
behaviour of mosi of the salts is like that of potassium chloride.
The cause of these phenomena is unknown The salts were as
pure as could be obtained. Electrodes of different materials
gave the same results. The radiation-tubes contained, of
course, a little mercury vapour, but none of the kno.vn com-
pounds of mercury with the constituents of the salts have the
colours above described. Chemical decomposition is unlikely,
since the coloured salt gradually changes into its original con-
dition. The author inclines to the view that during phosphor-
escence the particles of the salt have been m.ide to take up
positions and motions di:Tering from those of the unaltered
substance, and that a physical modification of the salt has thus
been brought about.

Some efforts have again been made in France to overcome
the air resistance which a locomotive encounters when running
at a high rate of speed. La Nature, for October 27, contains
a very interesting article by M. .Max de Nansouty, descriptive of
the experiment; of M. Kicour, originally made in 1887. In
these, inclined planes were placed in front of the engine, and
by adopting this means, making the slanting planes four in
three, and filling up the spokes of the wheels, the resistance
was diminished by one half. This resulted in a notable in-
crease of useful work, and an economy of ten per cent, on the
coal consumption. The results are so satisfactory that M.
Ricourhas fitted his apparatus on forty engines belonging to the
Paris-Lyon-Mediterrance Railway, for general traffic. Similar
experiments were carried out in 1890 by M. Dresdouit, chief
engineer to the State railways, and they were of more prolonged
character. The engines in this case were ran 300,000 kilo-
metres, and by means of this apparatus they saved six to eight
per cent, in coal consumption, and sometimes as high as twelve
per cent. M. Max de Sonly tells us, however, "il est vrai que
le chauffeur et le mccanicien ctaient excel lents." A few other
experiments were tried with seemingly the same satisfactory re-
sults. The main poini, however, thai, on an average, a benefit
of four to five per cent, is obtained by the use of thesi inclined
planes, and it is asserted thit this is more than the saving
obtained from locomotives with compound and other systems.
If the statemen t be true, our locomotive superintendents had

November 15, 1894J

NATURE

63

betler take heed, as nothing has yet been done in this direction.
We are not told, however, how the apparatus behaves with a
side wind.

We have received a catalogue of botanical works ofTered for
sale by Messrs. Dulau and Co. The books refer to the anatomy,
morphology, and physiology oi plants.

The Journal of the Sanitary Institute, vol. xv. part iii.,
contains the addresses delivered at the Congress held at Liver-
pool in September. Dr. J. F. J. Sykes contributes a report of
the proceedings of the International Congress of Hygiene,
Budapest.

Messrs. Blackie and Son have published the seventh part
of Kerner and Oliver's " Natural History of Plants." The new
part, which is just .as admirable as the previous ones, concludes
the section on climbing plants ; and deals with erect foliage
stems; the resistance of foliage stems to strain, pressure, and
bending ; the floral stem. It also contains the beginning of the
section on the forms of roots.

"Electric Lighting and Power Distribution," by Mr. W.
Perren Maycock, published by Messrs. Whittaker and Co., has
reached a second edition. The book is described as "an
elementary manual for students preparing for the preliminary
and ordinary grade examinations of the City and Guilds of
London Institute." It is profusely illustrated and clearly
written, and is altogether a good introductory text-book of
technical electricity.

Dr. Oscar GRt;Licil has prepared a history of the founda-
tion and growth of the K. Leopoldinisch - Carolinischen
Akademie der Naturforsctier at Halle. The volume is dedi-
cated to Halle University, which celebrated its bi-centenary this
year. The first president of the Academy was J. J. Baier, who
held the office from 1731 to 1735. Many eminent investigators
have occupied the president's chair since then, and Prof. Dr.
Knoblauch h.-xs held it since 187S. Dr. Grulich's book chiefly
deals with the famous library and scientific collections of the
Academy.

The third volume of Sir David Salomons' " Electric Light
Installations," dealing with the applications of electric energy,
has been published by Messrs. Whittaker and Co. It will be
remembered that the original work, " Electric Light In-
stallations and the Management of Accumulators," was in one
volume, and it was not until a seventh edition was demanded
that the division into three volumes took place. The present
volume is mainly concerned with the mechanical details which
interest the electrical engineer, and the workmen engaged in
electric installations, and to such we cordially recommend it. I

Science Progress for November contains five articles of
technical interest and importance. Dr. A. D. Waller, F.R.S.,
describes the state of knowledge of inhibitory phenomena ;
Mr. J. W. Rodger contributes the third of a series of articles on
the new theory of solutions. Recent researches in thermal
metamorphism are described by Mr. Alfred Harker. Mr. S.
H. Burbury, F. R.S., discusses Dr. H. W. Watson's " Treatise
on the Kinetic Theory of Gases" and a communication made
by Prof. Tait to the Royal Society of Edinburgh, " On the
Foundation of the Kinetic Theory of Gases." Finally, Prof.
A. C. Haddon gives a bibliography of the ethnography of
British New Guinea.

The "Division of Microscopy" of the United States
Department of Agriculture is publishing a very useful series
of small manuals under the title " Food Products." The first
three numbers deal almost entirely with edible and poisonous
fungi, with directions for their identification, and for the culture ,

NO. 1307, VOL. 51]

and preparation for the table of the edible species. They are
illustrated by excellent coloured and uncoloured plates. It is
a significent illustration of the wide distribution of the lower as
compared with the higher forms of vegetable life, that every
one of the twenty-four edible and twelve poisonous species of
fungus here described is a familiar European species. The
letterpress is written by Dr. Thomas Taylor, chief of the
Division of Microscopy.

The Meteorological Council have just issued a volume con-
taining the meteorological observations made at stations of the
Second Order, for the year 1890. Such observations have been
published in a more or less complete form since 1866, and the
present volume contains returns from sixty-eight stations, part
of the information being obtained from the English and Scottish
Meteorological Societies. A map shows the distribution of the
stations, which are well distributed over the United Kingdom,
although in some districts, especially in the West of Ireland,
there appears to be difficulty in obtaining good observers. In
addition to daily observations at many stations, the work con-
tains carefully prepared monthly and yearly summaries, and a
table showing the number of hours of bright sunshine for each
month at those stations which are provided with sunshine
recorders.

In 1815 there was published in Philadelphia the second
edition of a "Geographical, Historical, and Commercial
Grammar," by William Guthrie. This edition contained an
account of North American Zoology, by George Ord, which was
by far the most complete and accurate that had appeared.
Prof. Baird, in his work on the mammals of North America,
refers frequently to this contribution to Guthrie's Geography,
and his citations have helped to establish its importance. The
Academy of Natural -Sciences, Philadelphia, being desirous of
rescuing Ord's work from extinction, determined to reprint it.
After considerable difficulty, a copy of Guthrie's Geography
was found, containing marginal pencil notes by Ord, on the
zoological portion. This section of the book has now been re-
printed, with the notes, and to it Mr. S. N. Rhoads has added
an appendix on the more important scientific and historic
questions involved. The reprint will be heartily welcomed by
students of the systematic zoology of .\merica.

Helmholtz remarked, in the autobiographical address de
livered on the occasion of his jubilee : " Many a time when the
class was reading Cicero or Virgil, both of which I found very
tedious, I was calculating under the desk the path of rays in a
telescope, and I discovered, even at that time, some optical
theorems, not ordinarily met with in text-books, but which I
afterwards found useful in the construction of the ophthalmo-
scope." The enquiring student of the present time has no
difficulty in finding optical theorems not referred to in the text-
books in common use, for in most elementary manuals on
optics, the sections appertaining to lenses and mirrors are
treated inadequately. It ought to be recognised, however, that
a thorough knowledge of lenses and mirrors is the all-important
point of optics. To supply the deficiency of text- books in this
respect. Prof. R. C. Bodkin has prepared a little pamphlet —
" On Lenses and Mirrors, and the -Vutomatic Image-Finder"
(John J. Griffin and Sons) — in which he simplifies the study of
lenses and mirrors, and deduces the construction of micro-
scopes, telescopes, &c., from first principles. The image-
finder referred to in the title is an ingenious piece of apparatus
for illustrating the directions of the rays forming the image of
an object.

We do not often receive a catalogue of educational books,
scientific and technical treatises, and works of general know-
ledge prepared for use in Chinese schools. Therefore we have

64

NA TURE

[NOVEMBEK 15, 1894

looked with unusual interest through such a catalogue received
from "the well-known Chinese Scientific Book Depot, 407
Hankow Road, Shanghai." According to the title-page of the
catalogue, the works described have been translated or written
by Dr. John Fiyer ; and as there are nearly two hundred of
them, covering the whole fields of natural and physical sciences,
we confess to a reverential feeling for Dr. Fryer's marvellous
industry and encyclopedic knowledge. The translations
are moslly based upon standard English ur .American educa-
tional books, and are arranged into five series. There is the
"outline" series, for general reading and elemenlar)' instruc-
tion; the " handbook " series, for more advanced students;
the "temperance physiology " series, the " magazine " series,
adapted for school reading books ; and the "Imperial Govern-
ment " series, consisting of treatises, which together form a
valuable encyclopedia. As the avowed object in publishing the
works is the higher education |and intellectual enliLjhtenment of
the Chinese nation, we echo the hope that the use of the transla-
tions will continue to extend wherever instruction in scientific
subjects is given in the Chinese langnage.

The additions to the Zoological Society's Gardens during the
past week include two Wtiite-shafted Francolins (Francoliniis
leucoscepus) from North-east Africa, presented by Lord Lilford ;
two Nilotic Crocodiles (CrocoJilui niloticiis) from West Africa,
presented by Mr. J. A. McDiarmid ; four Hispid Lizards
(Agama hispiJa) Uoai South .\frica, presented by Mr. J. E.
Matcham ; an Australian Fruit Bat (PUropus poliocephalus
from .\ustralia ; a White-fronted \maiOQ{Chrysolis leucocefhala)
from Cuba, purchased.

OUR ASTRONOMICAL COLUMX.

.\ New Variable Star of the .Algol Tyte. — Dr. E.
Hartwig announced in the middle of September that the star
B.D. + 15-3311 (R.A. lyh. 53m. 36i., Decl. r i5"8*47"-2,
1900) was a variable of the Algol type. He afterwards deter-
mined the period to be 3d. 23h. 49m. 32s. 7. (Aslro. Xcuh. 3260).
It appears, however, that Dr. S. C. Chandler discovered the
character of the star's variability at the end of July, and com-
municaled his discovery 10 several other observers, who con-
firmed ii. The star was assigned the notation 6442 Z.
Hercules about the middle of August, the period having
previously been determined as 3d. 23h. 50m. Prof. Duncr
has found that the minima follow each other at unequal intervals
of forty-seven and forty-nine hours. There appears to be a
secondary miniuium which occurs a few hours previous to the
lime midway between two successive primary minima.

The Polar Cais of Mars. — Several sketches of Mars,
made at the Juvisy Observatory, by M. Antoniadi, accompany a
paper by M. Flammarion in the current Complci-rciia'us. 'fhe
lii;ures show clearly the slow diminution of ihe snow -caps of
Mars during the summer of the planet's southern hemisphere.
The summer solstice occurred on August 31, and the planet
was kept under observation from June 1 to November I. The
following are the resulis of the measures of the diameters of the
cap at Ihe south |>ole of Mars, on different dates : —

Diameter in kilometres.

3900

3000

2520

2100

iSoo

900

660

300

Encke's Com LT. — Prof. M. Wolf has found Encke's comet
upon a photograph taken on October 31, that is, a day
before Dr. Cciulli's obicivation, noted last week {.4i/r.
Nailt. 3262). The comet has been observed by M. Perrotin,
and IS naid to be at the entreme limit of visibilily of the twenty-
eight-inch refractor of the Nice Observatory.

Dale«

Vrcoccnlric arc

June I

0
65

.. '5

5"

July I

42

,. IS

35

August 1 ...

30

„ 23

'5

September 27

II

November 1

5

STATISTICAL ACCOUNT OF FRENCH
FORESTS.^
"V [ D.AUBREE, the Director of the French Forest Depart-
' ment, has recently published a statistical account, up to
the end of 1S92, of ihe French forests which are managed by
that department ; and as these forei^ts, especially in the northern
and central parts of France, greatly resemble those which might
be grown in the United Kingdom, and of which some badly-
managed examples are still to be found, a short notice of this
work will be interesting to those who wish to know what are
the possibilities of economic forestry at home.

The areas of the forests in question are as follows : —

.Acres.

Belonging to the State ... 2,691,165

,, communes and public estab-

lishments (hospitals, colleges, &c.) ... 4,738,637

Total 7,429,802

Or 11,609 square miles, one-eighteenth of the total area of
France, which is about 207,100 square miles.

No account is here taken of the private forests in Fiance,
which contain about 20,813 .square miles, so that the area of all
the forests in France is 32,422 square miles, or 15^ per cent, of
ihe area of the country.

Of the 7^ million acres of forest managed by the State, 18
per cent, of the Stale forests and 36 per cent, of the communal
forests are classed as unproductive or not stocked with trees.

.\ larger proportion of the Slate forests is unproductive be-
cause the Slate is constantly acquiring waste lands in order to
prevent denudation of mountains by torrents, or the encroach-
ment of sandy dunes ; whilst land belonging to the communes,
&c., which is not fit for re.iftbresting, is not generally handed
over to be managed by the State Forest Department.

Twenty excellent maps are attached to the report, and are
differently shaded so as to show the distribution of the forest
area among the different J.'partemcnts, according to ownership ;
mode of management (coppice, coppice-with-standards, high-
forest) ; annual degrees of productiveness — in material (cubic
metres per hectare) ; in money (francs per hectare) — and also
in oak and coniferous timber.

From these maps and the slalement which precedes them, it
may be readily seen that the State forests are most extensive
north of Lyons, and especially in Lorraine, Bourgogne, Isle de
France, Normandy, le Bourbon nais, and that in these provinces
there are scarcely any unproductive areas, which chiefly occur
in the south of France. The communal forests are also chiefly
in the east of France, or bordering on the Pyrenees and in
Corsica; this distribution depends on political and not on natural
causes, for the climate of the west of France is very favourable
to forest growth, and this region contains some magnificent
State forests and large areas of loiests in private hands. As
regards the mode of treatment, the State forests are distributed
as follows : —

Percentage of
tol.il area.

Simple coppice ... .. 2'5

Coppice-with-standards ... ... 29'2

,, under conversion 10 high forest... ... i6'8

High-forests 5r5

The simple coppice belonging to the State is chiefly situated
in ihe south, where the Slate shares in the produce with certain
communes, or the inhabitants have rights lo fuel, which pre-
vent any improvement in I heir treatment, and they are generally
composed of Qii{nu> //<m, which yields tanning bark, and fire-
wood rather than limber.

Coppice-with-standards is applied to large forest areas border-
ing on Belgium, and lo another series of Slate forests stretching
from the Jura towards Paris. These forests are generally
situated near large towns or the northern coal mines, and find
a ready sale for their somewhat branchy timber and underwood,
as building material, pit-props, firewood, &c., provided their
rotations arc long enough 10 exclude a large supply of charcoal
wood, for which the demands are being gradually restricted.

A large area of coppice- withstandatds, which is remote from
large towns and the coal mines, is being converted into high
forest, to increase the supply of timber as compared with fire-
wood.

I SlAtiftlique des forill toumises au r^zime forestier. Ann4! 1S92. Kx-
Irail clu liiillelin du Minisli^rc da jAgricullure. Parij : Imfrimirie
SationnU^ 1^9^

NO. 1307, VOL 51]

November 15, 1894]

NA TURE

6s

More than half the area of the State forests is already under

the high- forest treatment, and consists chiefly of highly-pro-
ductive silver-fir and beech forest in the Vosges ; forests of
finui Laricio and Fittus Pinaster in Corsica, which only yield
poor returns on account of the frequency of forest fires ; beech
forests in Normandy with a small proportion of oak, and ex-
tensive oak forests on the Loire and its tributaries, where beech
is kept subservient to the principal species. The maritime
pine forests of the Landes and Gironde yield large quantities
of resin and turpentine, as well as inferior timber, pit-props, &c.
The communal forests are distributed as follows : —

Percentage
of area.

Simple coppice >4'7

Coppice-with-standards ... 53'^

,, under conversion to high-forest ... I "o
High-forests 311

The communal simple coppice areas chiefly supply fuel to
villagers, and consist mainly of Qiierciis Ilex in the south, and of
common oak and other species in the Ardennes and lower
slopes of the Alps, near the villages and below the coniferous
forests of the higher zones.

Coppice with-standards is the commonest mode of manage-
ment of communal forests, and is distributed chiefly in the
temperate regions of hills and plains of the north-east of
France, and little of this area is being converted to high-forest,
as the people do not care sufficiently for the benefit of futurity to
sacrifice a considerable part of their present revenues.

The high forests belonging to communes, &c. , are chiefly
situated in the Vosges, Jura, .\lps, Pyrenees, and in Corsica,
consisting chiefly of conifers mixed with beech.

Detailed tables are given regarding the yield of the forests in
material and money.

Thus the production of the forests during the year 1892 was
as follows : —

-

State forests. Communal forests, &c.

Wood

Cork

Bark for tanning
Crude resin

c. feet ' c. feet.
96,051,592 169,275,133

CWt. CWt.
2,300 6,100
283,000 463,000
37,800 , 16,300

1

Total value

;^846,I44 /1, 321, 804
at 25 fr. = £1

The average annual production per acre of the wooded area
of the forests is as follows ; —

c. feet. s. d.

State forests ... ... ... 43.^ ... 9 5

Communal and other forests... 37 ... 5 10

It is evident that the State forests yield more wood, and of a
better quality, than the communal forests.

Leaving out the Departments of the Seine and Corrcze, where
the production in quantity of material and money is abnormally
high, the areas of State forests in these Departments being in-
considerable, the forests of the Vosges head the list with an
annual yield of 7'I36 cm. per hectare, equivalent to loi c. feet
^ler acre, and worth £\ y. 4^.

This reiurn is exceeded in value, though not in quantity,
by the forests of the Doubs, «here there is much oak grown as
well as silver-fir, and the yield i.s 5'867 c. metres per hectare
= 84 c. feet per acre, and worth £1 Ts. ^d. an acre.

The productiveness in different classes of material of the
<lifferent lorests are as follows : —

Timber

CoHifers.

Exceeding 20 in. in diameter .. ... 94

Less than ,, ... ... 5'3

Poles 06

Firewood ... ... ... ... ... -.. 7'7

The proportions of the yield of broad-leaved and coniferous
timber is as follows : —

Percentage.

Broad -leaved... ... ... 77

Coniferous .. ... 23

It is noted that the broad-leaved species yield 74 per cent, of
firewood, while the conifers only yield 33 per cent.

In the communal and other forests the production is as
follows : —

Percentage.

Broad-leaved ... Sl'3

Coniferous... ... ... ... .. ... 187

And the percentage of firewood in the former case is 86 per
cent., whilst for the coniferous forests it is 25 per cent. These
forests are less productive in timber, and especially in timber
exceeding 20 inches in diameter, than the State forests, which
accounts for their reduced money reiurn.

If we omit the large sum of ;{^g9, 300 spent in 1892 on planting-
up dangerous mountain sides and regulating the beds of
mountain torrents, and £?i,^oo spent on fixing shifting
sands, the cost of maintenance of the whole of the productive
forests referred to in 1892 was ;^397,o8o, or about Ij. 2d.
per acre, which must therefore be deducted from the yield
of the forests to determine their net revenues per acre.

The following is a complete statement of the French forest
charges for 1892 : —

Establishment... ... ... 231,800

Forest schools 6,SSo

Works of improvement in the forests ... 58,000

Mountain reboisenunt ... ... ... 99,300

Fixing shifting sands ... .. ... ... 8,400

Working plans and fellings ... ... ... 16,000

Management of (ha:ses which are not leased 2,000

Taxes ... ... ... ... ... ... 72,400

Law and other charges ... 10,000

;£ 504. 780

Of this amount £s,\,2(>%, or about 2d. an acre, is refunded to
the State by the communes and public estahlishments for the
management of their property. W. R. Fisher.

State Forests.
Broad-leaved Species.

( Oak 20 in. in diameter and above
Timber •; Do. less diameter

( Other broad-leaved species ...
Poles
Firewood ...

NO.

1307, VOL. 51]

Percentage of

yield.

• ■ s
s
61

.. 3-8
■■ 57-1

THE PROPERTIES OF LIOUID ETHANE
AND PROPANE.

A COMPREHENSIVE study of the properties of these
■^ primary hydrocarbons in the liquefied condition has been
made by Dr. Hainlen in the laboratory of Prof. Lothar Meyer
at Tubingen, and an account of his work will be found in the
current issue of Liebi'o's .Annalin. Owing to the greater
ease with which it undergoes liquefaction, propane was first
investigated. The hydrocarbon was obtained in a slate of
purity by means of the admirable method of preparation dis-
covered in the same laboratory in the year 1883 by Kohnlein,
which consists in heating propyl iodide with aluminium chloride
in a sealed tube to 130°. .\fter subjection to this temperature
for twenty hours the tube was allowed to cool, and subsequently
placed in a freezing mixture ; while immersed in the latter it
was found practicable to open it without danger or loss, the
accumulated gas being readily transferred to a gasholder over
w.'tter.

In order to determine the boiling-point of propane, the
purified gas was first condensed to the liquid state in a U-tube
surrounded by solid carbon-dioxide. It was then transferred
to the special boiling-point apparatus by evaporation and re-
condensation, the last traces of impurities being eliminated by
this process of repeated distillation. The special apparatus
consisted of a glass tube closed at the lower end, furnished
with a side tube for the entrance of the gas, and with a stopper
at the open end perforated for the passage of an exit-lube and
a thermometer. The upper h.ilf of the cylinder was surrounded
by solid carbon-dioxide, and the lower portion was protected
by a mantle of badly-conducting felt. Upon the entrance of

66

NATURE

[November 15, 1894

the gas the air was expelled by the exit-tube, and the gas which
condensed in the upper portion of the cylinder collected in the
lower portion. When the protecting mantle was removed the
relatively warm air soon promoted ebullition, and the escaping
vapour was as rapidly recondensed in the cooled upper portion
of the cylinder, and fell back into the lower. If the hand were
brought into the proximity of the cylinder, the boiling became
most vigorou-. At first propane usually boils irregularly,
.quiescent intervals being s^ucceeded by almost explosive ebulli-
tion ; bat after a short time the formation of vapour becomes
perfectly regular, and a mercury thermometer dipping in the
liquid registers a temperature of - 3S°. After comparison of
the latter with an air ihermouieler, the correct temperature of
the boiling-point of propane is found to be - 37" at 760 m.m.
pressure.

Propane may safely be sealed in strong glass tubes after con-
densation by means of solid carbon dioxide, and thus preserved
in the liquid state. It is a perfectly colourless liquid, Imt much
more viscous than liquid carbon dioxide. The critical tem-
perature was determined by use of such a tube half filled with
the liquid. The tube was immersed alongside a thermometer
in a bath of liquid paraffin, furnished with a suitable stirrer.
Upon heating the apparatus to 101° the liquid meniscus com-
menced to become hazy, and the distinction between gas and
liquid became less and less pronounced until at 1 10° all trace of
it had disappeared. Upon cooling, the well-known nebulosity
was observed at 102°, and this temperature is considered to be
a close approximation to the critical temperature of propane.

The vapour pressures of propane for different temperatures up
to I2^'5 were determined by enclosing a quantity of the
liquefied hydrocarbon in one limb of a U-tube and dried air in
the other limb, the two being separated by means of a short
column of mercury. The closed apparatus was then cooled to
various temperatures in suitable baths, and the vapour pressures
calculated from the amount of compression of the air column.
The vapour pressures for temperatures superior to the ordinary
were determined by use of the Cailletet appar.itus and spring
manometer. The following table represents a summary of the
results :

Pressure in

Pressure in

Temperature.

atmospheres.

Tcmpe

raturc.

atmosphere:..

-33'

1-8

-f

l»

S-'

-19

27

-f

5° 5

S'9

-«s

3'

-1-

I2»-S

71

-11°

3-6

-t-

22°

90

- s'

4«

4-

53°

170

- 2°

4-8

-f

8S°

350

+ 102°

48-5

The critical pressure of propane corresponding to the critical
temperature of 102° is consequently 485 atmospheres.

Dr. Plainlcn has also determined the density of liquid pro-
pane at several temperatures. It is 0'536 at 0°, 0524 at 6°'2,
0*520 at if'S, and o'5lS at I5°'9, compared with water at 4°.

An investigation of the properties of liquid ethane upon
similar lines naturally presented greater difficulties, on .account
of the further removal of its boiling-point from the ordinary
temperature. The j^ure gas cannot be so conveniently prepared
by the method of Kohnlein, as the sealed tubes frequently ex-
plode with great force. It was therefore obtained by the well-
known method of Gladstone and Tribe from ethyl iodide and
the zinc-copper couple. A mixture of ether and solid carbon
dioxide is insufficient to effect liquefaction of the gas, but liquid
ethylene was found to bring about the necessary reduction ol
temperature, which latter was mcasiircrl by means of a copper-
silver thermoelement. Liquid ethane in the pure state is
perfectly colourless.

The boiling-point of ethane was determined as in the cose of
propane, the upper part of the apparatus, however, being sur-
rounded by the liquid ethylene instead of solid carbon dioxide.
Thecthylcnc was j»rcvented frotii vapr>urising rapidly by allowing
the cxIreDicly cold vapour proiluced by the evaporation to pass
through an outer cylinder, and thus to act as a protective cold
bath. The ethane was first cooled by means of ether and solid
carbon dioxide before admission into the boiling-point
apparalun, after which it was found to be rapidly condensed by
the coMer ethylene. One end of the thcrmo-elcmcnt was im-
mersed in the accumulated liquid inste.id of a ihcrinometer.
The temperature of the liquid when in regular ebullition, pro-

NO. 1307, VOL. 51]

duced by removing the cap protecting the lower half of the
cylinder, «as found to be - S9°'5 at 735 m.m. pressure.

Liquid ethane cannot be sealed in a glass tube without con-
siderable danger. Hence the determinations of vapour pressure
and density were effected by the use of a modified Cailletet
compressing apparatus and spring manometer. The various
temperatures were obtained by surrounding the narrow thick-
walled glass tube in which the liquid was produced by suitable
baths. The critical temperature at which the curious cloudy
appearance was observed, just before the complete disappear-
ance of the liquid meniscus, was found to be 34'''S, and the
corresponding critical pressure 50 atmospheres. The meniscus
becomes hazy at 32" and only disappears completely at 40°, so
that the critical temperature, as in the case of propane, does
not appear to be so sharp as with many other liquids of low
boiling-point. The following table represents the vapoar
pressures lor a few intervals of temperature.

Pressure in Pressure in

Temperature, atmospheres. Temperature. atmospheres.

-31" II o^ 23-3

-20° 14-5 4-15° 32-3

-11° iS-3 -f34°-5 so

Prof. Dewar in 1SS4 determined the critical temperature and
pressure of ethane, and gave them as 35" and 45 '2 atmospheres.
M. Cailletet had previously stated that at -f 4" the gas exerted
a pressure of 46 atmospheres. Prof. Dewar's numbers are
now found to be in close accordance with Dr. llainlen's results,
and the older statement of M. Caillelet must therefore be taken
as founded upon an error.

The density of liquid ethane was found to be o'446 at 0° and
0-396 at + io°"5.

It may be interesting to compare the facts now established
with relerence to ethane and propane, with those previously
well ascertained for marsh gas and for normal butane.

I

Boiling point.

Critical
tempeiature.

Density in
liquid state.

164 (Olszewski) — 8i-8(01s«wski) 54 9 0-4 is*' -■'4
•i6o(\Vroblcwski) - 959 (Dewar) ■ 50
Ethane C"H(t |— 89 "5 at 735 m.m. -f 34"5 so 1 0-446 at o

Propane 0:tHs ;— 37'Q at 76oni.m. -hio2 48*5 0536 at o

«-UutancCiHioi-h i — | — 060 at o

' (RonaMsi865>

If the above boiling-points are represented graphically alonjj
with those of the higher normal paraffins, molecular weight or
the number of carbon atoms being taken as absciss.-e and boiling-
point as ordinates, a perfectly regular curve is obtained, slightly
concave towards the axis of abscissa!, which very clearly indi-
cates the dependence of the boiling-point upon the molecular
weight. A. E. TUTio.N.

THE BRITISH CENTRAL AFRICA
PROTECTORATE.

lyr R. 11. II. JOHNSTONE opened the session of the Royal
•'■'■'■ Geographical Society on Monday evening with a jiaper on
liritish Central Africa, of which he is administrator. He con-
trasted the condition of the country ten years ago with what it
is now, explaining how the Mission schools, the .Scottish
planters, an 1 the Sikh police had produced changes in the
manners, productions, and means of tr.insport of the whole
region, and had succeeded in effectually repressing the slave
trade. A survey of the Protectorate has been in progress for
the last three years, and the map is beginning to acquire some
firmness of outline. The great advantage of the Protectorate
over the surrounding dislncls lies in the greater proportion of
high land over low swampy country. Roughly speaking, about
four-fifths of its land-surface is 3000 feet and upwards above the
level of the sea, and about onc-lifth is between 5000 and 10,000
feet. The immediate result of this elevation of the land is the
prevalence of a much cooler climate, than is usually found in
Central Africa so near the e<iuator. There arc portions of
British Central Africa where the heal is never oppressive, even

November 15, 1894]

NA TURE

67

jn the hot season, and where in the cold season bitter froits pre-
vail. Unfortunately, it is impossible to reach this delectable
.land from the coast withuat tiaversing the hot and unhealthy
valleys of the Zambezi and Shire.

There is an average rainfall ol 55 inches throughout the Pro-
tectorate, but it is not altogether uniform in character, some
districts receiving about 75 inches, and others not more than 35
inches. Still, it is decidedly a well-watered country, endowed
with many perennial streams, only a small number of which
dry up in the height of the dry season. Consequently, it is a
land which can almost everywhere be irrigated during the dry
season, and can thus grow a continual succession of crops. The
water is almost everywhere wholesome to drink.

The great attraction of the country lies in its beautiful
scenery, in its magnificent blue lakes, its tumultuous
cascades and cataracts, its grand mountains, its goMen
plains and dark green forests. A pleasant and peculiar feature
also of the western portion of the Protectorate is the rolling
grassy downs, almost denuded of trees, covered with short tur(,
<juile healthy, and free from the Tsetse fly ; these no doubt will
in the future become actual sites of European colonies, districts
in which Europeans can rear their children under healthful
conditions.

The lofiy plateau of Mlanje is a little world in itself, with
the exhilarating climate of Northern Europe. These plains
and valleys ace gay with blue ground-orchids, with a purple
iris, and with yellow everlasting ilowers. Here and there great
rocky boulders stand up in stern relief against the velvet turf,
and out of these elevated plains again rise other mountains,
gloomy in aspect and remarkably grand in outline. The
loiesis, on cloicr inspection, turn out to be mainly composed
•jf the handsome conifer IVuldringlonia Why lei.

No one has succeeded in reaching the highest summit of
Mlanje. Mr. Johnston ascended about as lar as 9300 feet,
and, estimating that there were fully 700 feet more ot'ascent,
approximately fixed the highest point at 10,000 feet. The
ascent of this high peak is tendered very difficult by the enor-
mous size of the boulders with which it is strewn. The whole
mountain mass of Mlanje probably occupies, with its outlying
peaks connected by saddles, an area of 1600 square miles, of
which 200 .'■quare miles consist of these level or gently un-
dulating plateaux, admirably suited for European settlements.
-Many of the salient features of Mlanje are repeated in the
striking mountains of Nyasaland, with the exception of the
cedars, which, however, are reporteil to exist on one or two of
the highest peaks ol Zomba, but have never been seen else-
w here.

The low plains surrounding Lake Nyasa and bordering the
rivers ofler a sharp contrast to the plateaux. Zebras, harte-
beests, water-buck, pallah, roan antelopes, and reed-buck may
be found in numbers, often dwelling gregariously together
t)n these hot plains ; and a few vultures, eagles, kites, and
Marabout storks wheel and float overhead in the dazzling
bluish-white sky, on the look-out for offal. The sable antelope,
the eland, the kudu, and the bush-buck seem to prefer the
sparsely forested hill-slopes to the flat plain, where there is
usually much less cover. The rhinoceros still ranges over these
plains, and wallows in the stagnant pools of the half-dried
livers. The heat prevailing on the plains in the summer-time
is very great — almost overpowering — but in the winter and
spring the air is exhilarating.

The Uritish settlements have now a settled and comfortable
appearance, with uniformed native policemen and trained
natives from the Mission schools working as printers and even
as telegraph operators at HIantyre. The most interesting feature
tn the neighbourhood of these settlements at the present time
is the coffee-plantation, which, to a great extent, is the cause
.and support of their prosperity. The variety which is cultivated
in the Shire highlands was actually introduced from Scotland,
having been derived from a small plant sent from the Edinburgli
£otaiiical Gardens to Blantyre about sixteen years ago. From
this plant the greater part of the five million cofiee-trees now
.growing in this part of Africa ate descended, while the original
mother tree is still alive in the Mission grounds at Biantyre.
The climate and soil of Nyasalantl would seem to suit the coffee-
tree to perfection, and iheciops given are unusually large. As
jet Nyasaland has been free Irom the cofi'ee disease, which, as
in Brazd and India, does not appear to be able to penetrate far
inland from the coast, though it has already committed ravages
iu German East Africa and in Natal.

EARLY BRITISH RACES.^
TDEFORE proceeding to trace the early history of man in
^ Britain, it is necessary to refer briefly to the physical
changes which geologists tell us have occurred since the close
of the Tertiary period in the configuration and temperature of
the north-western portion of F^urope.

At the beginning of the Plei>tocene period, the temperature
of Northern Europe became colder, and an ice-cap, like that
which now covers Greenland, gradually extended itself pro-
bably as far south as Middlesex, and covered the greater
part of Wales and the northern half of Ireland. This epoch
is known as the Great Ice Age. .M that time also the land
was more elevated than now, so that Great Britain and Ireland
formed part of the continent of Europe, and the western coast-
line extended some three or four hundred miles further
into the Atlantic Ocean than it does at present. This period
of cold was succeeded by a more genial one, during which,
but before the ice had disappeared, a great submergence of land
and of the glaciers still upon it took place, varying at different
parts of the country from 600 ft. to over 3000 ft. The
climate again became colder, and on the higher parts of
Wales, the North of England, and Scotland, glaciers were
formed once more, but not to the same extent as for-
merly. Then followed, in late Pleistocene times.a re-ele-
vation of the land to at least 600 feet above the present
level. Great Britain and Ireland once more became joined
to the continent, and the climate became temperate. In all
probability the geographical conditions of Britain, or rather
the British corner of Europe, in early and late Pleistocene
times, were almost identical. Finally the land connection with
the continent became severed by submergence, which went on
till almost the present coast-line was reached ; the sea once
more rolled in over the beds of the German Ocean and the
English Channel. These changes in the geographical confor-
mation of the north-western part of Europe took place slowly,
and were consequently s[)read over an immense interval of time.

According to some eminent geologists, man first took up his
abode in the British portion of Europe, either during the early
glacial or pre-glacial period. The evidence of his existence
here at that early period rests upon the discovery of many flint
implements of peculiar and special type on certain high chalk
plateaus in Kent in drift renting on Pleiocene beds, in drift de-
posits of Norfolk and Suffolk, and in certain caves in which
glacial drift is believed to be deposited over the flints. All
these implements are of the rudest make, more or less stained,
like the drift flints with which they are associ-ited, of a deep
brown colour. They show a considerable amount of wear, as
though they had been ruljbed and knocked about a good deal,
so that the worked edges ate commonly rounded off and blunt.
In few instances have the implements been wrought out of
larger flints, and the amount of trimming they have received is
very slight, and has heen generally made on the edges of rude
natural flints picked up from old flint drift ; indeed, sometimes
she work is so slight as to be scarcely apparent ; in other speci-
mens it is sufficient to show design and object. These imple-
ments indicate the very infancy of art, and are probably the
earliest efforts of man to fabricate tools and weapons from other
substances than wood or bone. They give us some slight in-
sight into the occupations and surroundings of the race who used
them, as they appear to have been employed for breaking bones
to extract the marrow, scraping skins, and rounding sticks and
bones for use as tools or (loles. From the absence of large mas-
sive implements, it would seem as though offensive and defen-
sive weapons had not been much needed, either from the
absence of large mammalia, or from the habits and character of
these early people. Many archaeologists are not saii^hed with
the 'evidence )et adduced as to the age of these flints, conse-
quently of man's existence in Britain at this early ilaie. and the
(juestion cannot be considered settled one way or omcr.

Whatever may be the ultimate decision as to the existence of
l)re-glacial man in Britain, all geologists and others are agreed
that alter the glacial period had pa-sed away, and Britain had
once mote become a part of the continent of Europe after its
submergence, a race of men known to us as Palaeolithic man
migrated into the country from the continent, across the valley
of the English Channel, in late Pleistocene times. Man of this
period is known to us from remains found in the river-drifts of
1 .A lecture delivered .it the Royal Inslilulion by Dr. J. G. Garson. We
are indebted to Prof, li^yd Dawk.ns fvrpcnnission to use the acconipanyins
illusliations.

NO. 1307, VOL. 51]

68

NATURE

[November 15, 1894

post-glacial age, and in the lower deposits oi certain caves. As
some evidence has been brought forward to show that the river-
drift people, as they are called, are earlier than the cave-
dwellers, we will consider the river-drift people first.

Remains of man from the river-drifts have only been found
in the south of England from Chard, Axminster, and the Bristol
Channel, in the west to the Straits of Dover, the lower Thames,

SufTolk, and Norfolk on the east, and as far north as Cambridge.
They are conspicuous by their absence north-west of a line
passing from Bristol to the Wash. The remains consist of a
small porti'in of a skull, reputed to be of this period, imple-
ments of flint, quartzite, and chert, antlers of deer, and of
certain fossil shells, probably used as ornaments.

The portion of skull was found by the late Mr. Henry Prigg,

n-.

A

<i.

'<^

in 1882, at Weslley, in .Suffolk, seven and a half feet from the
surface, in a pocket of brick earth eroded in the chalk, and in
an adjoining pocket two molar leetli uf mammoth and four
I'al.colithic flint implement* were found,' The fragment of
ikull was part of the vertex, and included the upper portions of
the frontal and parietal bones, with part of the coronal and
sagittal sutures. It wa« examined by Mr. Worthington .Smith,

' / //'. .\nihro/>. /ml , vol. xiv. p. 51.

NO. 1307. VOL. 51]

and in transit to the finder of it was unfortunately smashed. As
it was not a characteristic part of the skull, it shed little light
on the cranial characters of its owner. With this exception, no
human bones have been found in fluviatile deposits in Britain.

The implements from the river-drift consist principally of
oval-pointed flints which have been fashioned by chipping, and
were used without handles, oval or rounded flints with a cutting
edge all round, scrapers for preparing skins, pointed flints used
for boring, flakes struck ofl^ from blocks or cores by means of
large hammer-stones, often of quartzite, and choppers of pebbles
chipped to an edge on one side. The tools with which these
implements were manufactured consisted of anvil stones of
large blocks of flint, pointed flints or punches, and carefully

'C

KiG.

Fic. 5.

made fabricators. All the implements, though simple and
rude, show signs of manufacture, the more finely finished speci-
mens having been prepared by delicate chipping. Their manu-
facture seems to have been carried on at certain spots, on the
banks of rivers and other places, where there was plenty of
material to make them from. It will be observed that ;\t this
time there were no flint arrow-heads, and that man was but poorly
equipped for the chase, although it was undoubtedly by that
means he gained his livelihood. Besides these flints, man doubt-
less used wood and bone implements ; indeed, pieces of pointed
stakes of wood have been found on the Paleolithic floors where
he worked, by Mr. Worlhington .Smith. Bead-like fossil shells

of Cosciiwpora nlobulosa have been found by Mr. Smith, with
artificial enlargement of their natural orifices, which would
indicate that they had been used for necklaces or amulets,
so that primitive man seems not to have been without his
personal adornments even at this time.

It is of importance to consider for a moment the animals
which lived with man at this period. There are found in the
same slrata with him remains of the hippopotamus, two species
of elephants and of rhinoceros, the cave bear and lion, the wild
cat, h).ina, urus, bison, the wild horse and boar, stag, roe, rein-
deer, and other animals, many of which are now exlinct. Man
at that lime had no domestic animals. The only clothing he
had, if he wore any, was made from the skins of the animals he

November 15, 1894J

NATURE

69

killed in the chase and used for food. Being far from the sea,
if he used fish as food, they would be such as he was able to
catch in the rivers.

Let us now trace man of this period on the continent. In
the fluviatile deposits of the Somme and the Garonne, stone

Fic. 8.

implements have been found and recognised by such com-
petent authorities as Sir John Evans, Mr. Franks, Prof. Boyd
Dawkins, and others, as identical with the drift Palaeolithic
implements found in England. Similar ones have been

Fig. 9.

found in Spain, near Madrid, in Italy, Greece, Germany,
and other places in Europe ; also in Northern Africa,
Palestine, and India. From these finds we learn that man has
lived in a similar state of civilisation to what he did in Britain,

be made to these specimens when we deal with the cave
skeletons.

Caverns and rock shelters are well known to have been used not
only by man, but also by animals, from remote times down to the
present day. The strata which have been deposited in them at
different limes by their successive occupants, and the vicissitudes

'jfj^\^'^\z

Fig. 14.

of climate, are often well marked, and give much valuable and
reliable information, but great care is required in discriminating
the different periods which their contents represent. The
emains of Paleolithic man deposited in caves are much more

^^'■M^^

Fi.,. I

over a very wide area ; they also show that he must have
existed in this stage of culture for a very long time.

As regards his skeletal remains on the continent, a few have
been found. At Canstadt, near Stuttgart, it has been stated that

widely distributed over England than those from the river-drifts,
having been found as far north as Yorkshire and Derbyshire,
in North and South Wales, Gloucestershire, Monmouthshire,
Somersetshire, and Devonshire, also in Ireland, although these

irtion of a skull was discovered, in 1 700, in loess deposits, with

ines of the cave bear, hya'na, and mammoth. At Eguisheim,

nearColmar, Schaflfhausen, portion of another cranium was found

with mammoth and other animal remains of this period. At

Fig 12.

Clichy, in the valley of the Seine, a skull and some bones were
found at depths varying from 4 to 5 '4 metres from the surface in
undisturbed strata, with mammoth, woolly rhinoceros, horse,
and stag. The skull in these instances is long and narrow in

shape, with very prominent supraorbital ridges and glabella ;
the thigh and leg bones of the Clichy skeleton are laterally
■compressed, the former having a greatly developed tinea aspcra,
the latter being markedly platycnemic. Further reference will

NO. 1307, VOL. 51]

latter have not been much worked. The Paleolithic cave strata
shows three sub-strata ; in the two lower ones the flint imple-
ments are precisely similar to those of the river-drifts, but flat
pebble implements of quartzite are also found with part of the

Fig. 15.

natural smooth surface retained, while the rest is chipped and
fashioned into an implement.

In the upper substratum more highly finished articles, which
would point to a higher and probably a difierent social condition,
later in time, are obtained. We have in this higher substratum
flints of oval and lanceolate form, trimmed flakes, borers,
and rounded hammer-stones (Figs. I, 2, 3, 4, S^ ^> ^■'•^
7). These are of smaller size than the earlier implements,
and some of them had evidently been let into handles of wood.
Bone ntedles, with an eye bored .at one end (Fig. 8), bone
awls (Fig. 9), scoops (Fig. 10), and harpoons (Figs. II and 12),
barbed on one or both sides of deer's antler, are also met
with. Of great importance ate the representations of animals
which have been found incised on bone, as, for example, the

NATURE

[November 15, 1894

portion of rib with the incised figure of a horse upon it, found
in this layer in Robin Hood Cave in Derbyshire (Fig. 13).

No portions of the human skeleton have been found in the
Palseolithie stratum of British caves, except a single tooth.

On the continent many caves have been discovered in France,
Belgium, Germany, and Switzerland, with similar deposits and
implements to those found in England, and showing also the
same two stages of culture. More numerous examples of figure
carving of the same type as that found in the Derbyshire
cave have been obtained in French caves (Fig. 14), and the
teeth of carnivorous animals and shells, both artificially bored
for ornaments (Fig. 15).

By associating British and continental evidence we can form
a good idea of the mode of life of the cave-dwellers of Paleo-
lithic times. The caves gave him shelter in cold weather, from
which he further protected himself by fires, and clothing made
from the skins of animals he secured in the chase, sewn together
by means of bone needles and tendons of reindeer for thread.
.■\rmed with flint-tipped spears and daggers of bone ornamented
with carved handles representing the chase, he lived by hunting
the reindeer, the wild horse, and the bison ; he also lived on
birds and fish, which he speared with barbed harpoons. The
game he brought home was cut up with flint knives, and cooked ;
the long bones were broken with heavy flints for the marrow
they contained, which was evidently considered a delicacy.
When not engaged in the chase, the manufacture of flint im-
plements must have formed an important part of his home work.
He must also have spent much time in carving ornaments on
bone. These, it may be remarked, show that he was an artist
of no mean order in depicting animals, but give us little in-
formation regarding his own form, as he seldom represented
himself, and when he did he figured himself in miniatures and
naked (Fig. 14I ; they also show that he was in the habit of
wearing long gloves to cover his hands and arms (Fig. 15).
Besides ornamenting himself with perforated shells, pieces of
bone, ivory, and teeth, he probably painted his body of a red
colour. He, like the river-drift people, possessed no domestic
animals, and had no dog to assist him in hunting.

{To be continued.)

UNIVERSITY AND EDUCATIONAL
INTELLIGENCE.

Cambridge. — Dr. J. Lorrain-Smilh has been appointed
Demonstrator in Pathology, in the place of Mr. L. Cobbett,
who has been elected to the John Lucas Walker Research
Studentship.

An Isaac Newton Studentship in Astronomy, worth ;^200 a
year for three years, will be vacant in the Lent Term. Candi-
dates must he B.A.'s under the age of 25 on January i, 1895.
Names and testimonials are to be sent to the Vice Chancellor by
January 31, 1895, with a statement of the course of study or
research proposed.

At the biennial election to the Council of the Senate, held on
November 7, Dr. Peile, Mr. C. Smith, Dr. Maitland, Dr.
Sidgwick, Dr. D. Macalister, Dr. Forsyth, Mr. Whitting, and
Mr. K. T. Wright were returned for a period of four years.

Dr. Donald .Macalister was, on November 9, elected with-
out opposition to represent the University on the General
Medical Council for a second term of five years.

This year has been memorable as the twenty-first anniversary
of the establishment of the University Extension lectures, the
system having been founded by the University of Cambridge in
the year 1873. The twenty-first annual report of the Cam-
bridge Syndicate has just appeared. During the past session
seventy-five science courses have been delivered at various
centres. This number is less than those of the last two or three
years, the diminution being attributed almost entirely to the
decrease in the temporary work undertaken by the Syndicate
during the preceding sessions for the technical instruction com-
mittees of various County Councils. Whereas in some places
grants of money from the local authorities have enabled local
committees to arrange more easily courses of University Local
Lectures on scienlilic subjects, in others the cheap technical
classes organised independently by the lo;al authorities have
influenced very injuiiously the attendance at the local lectures,
and in some cases caused their discontinuance. The County

NO. 1307, VOL. 51 J

Councils are just beginning to feel their feet, but it 'seems
ungenerous of them to forget that they were helped over
their initial difficulties by University Extension Lectures.
The Technical and University Extension College at Exeter,
which is under the joint management of the local authorities
and the Cambridge Syndicate, has nosv completed its first
session's work, and about six hundred regular students have
already joined the College. Its success affords a striking illus-
tration of the method by which under the Local Lectures system
permanent educational institutions can be established. It should
not be forgotten that the Cambridge University Extension
movement was similarly largely instrumental in the foundation,
a few years ago, of University College, Nottingham, Firth
College, Sheffield, and other local colleges.

The London Technical Education Gazette, the first number of
which has just been published, is intended to contain the official
announcements of the Technical Education Board of the London
County Council ; notices of important steps in technical educn-
tion taken by the various institutions in London ; and useful
information bearing upon the work. In the list of the con-
ditions which have to be fulfilled by evening classes in science,
in order to obtain grants from the Board, we are glad to note
the following : — " That as a condition of aid being granted by
the Board for the teaching of chemistry, metallurgy, physics,
mechanics, and botany, it will be regarded as indispensable
that provision should be made, to the satisfaction of the Board,
not only for the experimental illustration of the lectures or class
teaching, but for experimental work by the students themselves,
either in laboratories belonging to the institution, or, where this
cannot be arranged, in the laboratories of some neighbouring
institution with which the class should be associated ; and every
lecture must be followed by at least one hour's practical work
on the fame evening, or some other evening in the same week."

SCIENTIFIC SERIALS

iViedemann's Annalen Jer Physik und Chemie, No. II. — Ex-
periment.il researches on the origin of fnctional electricity, by
C. Christiansen. Friction by itself does not generate electricity.
The appearance of the latter is due to chemical decompositions
which are initiated by contact and completed on separation.
These results are those of experiments with a tube coated on
the inside with various insulators, .arranged so that mercury
could be brought into contact with them and withdrawn, after
which a charge was indicated by a galvanometer. — On thermo.
couples of metals and saline solutions, by August Ilagenbach.
In the case of couples consisting of metals and their talis, tlie
E.M.F. increases with the dilution, and more rapidly than the
difference of temperature. In combinations of platinum with
hot and cold saline solutions the same acids give about the same
forces, and dilTercnces of concenttation have a very marked
influence. Thehighcst E.M.F. obtained was thatof aplatinum-
cupricchloridc couple, which, with a j'6 per cent, solution,
and with the two communicating portions of the liquid at 25°
and 80" respectively, gave an E.M.F. of o'l54l volts. — Changes
of length produced by magnetisation in iron, nickel, and cobalt
ellipsoid", by H. Nagaoka. The optical lever method was
employed. As the field intensity increases, iron first expands
and then contracts, going through the opposite stages on revers-
ing, and showing a decided hysteresis. Nickel simply contracts.
Cobalt contracts first and then expands, the expansion increas-
ing to a limiting value as the field intensity increases. — On
elliplically-polariscd rays of electric force, and on electric
resonance, by L. Zehnder. The author shows how to produce
circularly and elliptically polarised electric rays by two wire
gratings placed one behind the other, with the directions of
wires crossed. — On refraction and dispersion of rays of electric
force, by A. Garbasso and E. .\schkinass. To produce a prism
capable of affecting ether waves of the length of those due to
Hertzian oscillations, a prism was constructed of a series of
parallel glass plates, upon which were stuck " resonators " made
of strips of tinfoil. This was placed between an exciter and a
suitable resonator. It was found that the rays were refracted
by angles differing according to the wavc-lcnglli. The deviations
for three different resonators were 9° 6', 7° 18', and 5" 24' re-
spectively.

November 15, 1894J

NATURE

71

SOCIETIES AND ACADEMIES.

London.

Physical Society, October 26. — Prof. A. W. RUcker, F. R. S. ,
President, in the chair. — The meeting was held in the rooms of
I the Chemical Society, Burlington House. — In opening the pro-
ceedings the President said the occasion might be regarded as
another sign that the boundary between Chemistry and Physics
was breaking down. On behalf of the Council he tendered the
I thanks of the Physical .Society to the Chemical Society for the
1 use of the rooms. — Prof. H E. Armstrong, President of the
\ Chemical Society, said his Council offered a cordial welcome to
', the Physical Society. The change, he thought would prove of
much greater importance than a mere removal. Now that the
childhood of the Physical Society was passed, its manhood
involved new responsibilities, and great opportunities for good
presented themselves. The Physical Society of London
ought now to become the head-centre of physics in the United
Kingdom. He (Dr. Armstrong) was pleased to learn that the
Society had undertaken the preparation and publication of
abstracts of physical papers appearing in foreign periodicals, and
said the matter was of such great importance that it should be
done thoroughly. In a work of such a magnitude, he regarded
the co-operation of other societies, such as the Institution of
Electrical Engineers, as absolutely necessary. — The President, in
acknowledging the welcome, said the Physical Society was
extremely obliged to the President and Council of the Chemical
Society for the great benefits conferred. Dr. .Armstrong's
ailvice to go ahead would not be forgotten. He then announced
that at future meetings tea would be provided for members at
4. 50. — The exhibition of a voltameter by Mr. Naber was post-
jjiined. — Mr. E. H. Griffiths .read a paper on the influence of
temperature on the specific heat of aniline. After pointing
out that most observations of specific heat depend on water,
whose capacity for heat varies considerably with temperature,
the author said large differences existed between the values
obtained by different observers as the latent heats of evaporation
of water and other liquids, and these differences were probably
due to the variability of the water standard, which had been
erroneously assumed constant. Precise measurements in calori-
metry were of such great importance that the exact relation
between the capacity for heat of water and its temperature
should be completely determined. With apparatus such as he
had used with aniline, this could be done in six months, pro-
vided someone could be found who could devote his whole time
to the subject. The results of his own experiments were ex-
))ressed in terms of the capacity for heat of water at 15' C. (at
which J = 4'I98 X lo'" ergs.), and hence were referred to
a definite standard. A great desideratum in calorimetric
work was a calorimeter whose ^surroundings could be kept
at a very -constant temperature. This he had obtained by
using a tank holding about 20 gallons of water, in which
a steel ve^sel, shaped like a hat-box with lioilow sides and
bottom, was immersed. The cavity w.is filled with about 70
pounds of mercury, and served as the bulb of a thermometer ; a
nilie communicating with this bulb acted as a regulator to
Liiutrol the gas supply which healed the water in the lank.
The tank water was circulated rapidly by a screw-propeller.
L'nder ordinary conditions the temperature of the outside of the
steel chamber could be kept constant within i/ioo" C. The
calorimeter itself was of brass, and suspended by glass tubes
from the lid of the steel chamber. A stirrer worked by an
electromotor kept the contents in rapid motion. In the experi-
ments on aniline, heat was supplied to the liquid in the interior
by maintaining known potential differences (equal to some
multiple of the E. M.F. of a Clark's cell) between the ends of a
coil of German silver wire placed inside. The rate of rise of
temperature of the inside over the outside was measured by
platinum thermometers, one of which was placed in the
calorimeter, and the other embedded in the walls of the
steel vessel surrounding the calorimeter. By this means differ-
ences in temperature of i/iooo of r C. could be detected with
certainty. A special method of adjusting the potential differ-
ence between the ends of the German silver wire was employed,
by which the constancy could be maintained within i part in
I0,ooo. To minimise corrections arising from heat generated
by stirring the liquid, and that lost by radiation, &c., from the
calorimeter, the ex[>eriments were made about temperatures at
which these corrections balanced each other ; the rise of tem-
perature was then due to the electric supply alone. The

specific heat, S, of the liquid at temperature flj could then be
determined from the formula

dt JRj(SiM + a/i)

where — i = rate of rise of temperature at temperature flj

J = mechanical equivalent of heat,
E = potential difference between the ends of the coil,
R] = resistance of the coil,
M = mass of liquid,
and u\ = water equivalent of calorimeter at temperature 9;.

Experiments were made with different values of E, and two
widely different masses of liquid were used. The author was
thus enabled to find S, without knowing vi^. Having found
S,, the water equivalent of the calorimeter could then be
determined. Many important details of construction and
manipulation of the apparatus, as well as the method employed
in reducing the results, are given in the paper. The final values
(or Si and w^ at several temperatures are given below.

Specific heat of Water etjtiivalent of

.iniline. calorimeter.

0-5137 79'82

Temperaturt.

is°c. ..

20 o'SiSS So-ii

30 o'5i98 8o'9o

40 o'S244 S2-I9

50 05294 83-39

The aniline employed was supplied by Messrs. Harrington
Bros, as "pure colourless," but had initially a light brown
tinge. After being in use some time, the colour had darkened
considerably, but its specific heat had not sensibly changed.
Recently he had tried a hydrocarbon liquid which promised to
be still more satisfactory as a standard liquid in calorimetry.
In the course of his remarks the author said a name for
"capacity of heat per unit volume" was greatly needed, and
invited suggestions. Dr. Armstrong thought the author had
made a particularly happy selection in aniline, for it could now
be obtained in any quantity absolutely pure. When pure it did
not discolour on exposure, and would probably be very satis-
factory as a standard liquid. He doubted whether any hydro-
carbon could be better. Prof. Ayrton congratulated the author
on the extreme accuracy (obtained. Recently he had arranged
an experiment for determining the mechanical equivalent of heat
by the electrical method, which gave very accurate results
without any corrections whatever being necessary. Prof. S. P.
Thompson thought the whole phraseology of specific heat
required revising. Prof. Perry agreed with Mr. Griffiths that a
name for "capacity for heat per unit volume" was greatly
needed, and Mr. Lucas suggested "heat density," but this was
not satisfactory. Dr. Sumpnersaid most text-books on physics
attribuledithe advantage of the mercury thermometer to the low
specific heat of mercury, whereas the capacity for heat per unit
volume was the important factor. Mr. Watson inquired to
what temperature the alloy which the author had used lo connect
glass to metal had been tested? The President said the paper
was of great impDrtance because it dwelt with the application
of electrical methods to thermometry. The mercury thermo-
meter had been quite superseded for work such as had just been
described. Mr. Griffiths, in reply to Mr. Watson, said the alloy
had been used successfully between 10° and 62" C. It gave
way at 71° C. lie was glad to learn from Dr. .\rmstrong that
aniline could now be got ))ure. Prof. Ramsay had written to
say he did not think the slight impurities in ordinary aniline
would have much effect on its specific heat. Mr. Blakesley
asked if aniline could be taken as pure if it did not change
colour on exposure. Dr. -Armstrong, in reply, said yes, if the
boiling point was also constant.

Paris.
Academy of Sciences, November 5. — M. Loewy in the
chair. — On an apparatus serving to demonstrate certain con-
sequences of the theorem of areas, by M. Marcel Deprez. This
is an apparatus designed to show that a body passing freely
through s| ace may rot.ate on its own .axis without suffering the
application of any exterior force, such rotation being produced
by interior movements of parts of its system. — On the theorem
of areas, by XL P. AppcU. — On the theory of flow for a weir
with depressed or partly submerged liquid sheet, in the case
where a horizontal armature gives the inferior maximum con-
traction, by M.J. Boussinesq. — On the vaporisation of carbon,
by M. Henri Moissan. The heatof the electric furnace enables

NO. 1307, VOL, 51]

72

NATURE

[November 15, 1894

carbon to be volatilised : the sublimed carbon is always deposited
nnder the form of graphite at ordinary pressures, and there is
no evidence whatever of the liquefaction of the carbon, for
instance the lid of a carbon crucible did not adhere when the
whole mass had been converted into graphite, and a carbon
needle heated in a carbon tube did nit in any case become
attached to the latter. Previous experiments have, however,
shown .that under great pressures carbon may be fused, and
diamond is then formed. — New observations on the menhirs
of the Meudon woods, by M. Berlhelot. — Note by M. Maurice
Levy accompanyinc the presentation of his " Study of the
mechanical and electrical methods of traction of boats." The
author gives a short account of the contents of the first volume
of his work dealing with cable traction only. — M. Bouquet de
la Grje, in the name of the Bureau des Longitudes, presented
the " Connaissance des Temps " for the year 1S97. This volume
con!ains, en the maps of solar eclipses, the curves passing
through the points on the earth at which the commencement
and end of the eclipse are simultaneous. The ecliptic elements
of the great planets and their satellites, including their elonga-
tions and the elements of Saturn's ring, are also given.- —
Observations of the new planet BE, made at Paris Observatory,
by M. G. Bigourdan. — The polar snows of Mars, by M. C.
Flammarion (see " Our Astronomical Column "). — Relations
between the vapour pressures of a body in the solid and
in the liquid state : influence of pressure on the temperature
of fusion, by M. A. Ponsot. — Influence of form on the
sensitiveness to light and aberration of the eye, by M.
Charles Henry. — Researches on mercuric nitrates, by >L
Raoul Varet. The heats of formation are determined.
In the dissociation of mercuric nitrate by water the least
endothermic of the possible reactions is the one that
takes place. Nitric acid, like sulphuric, picric, acetic, and
oxalic acids, is displaced completely from mercuric combinations
by hydrochloric and by hydrocyanic acids. — On thecanipholenic
acids and the campholenamides, by M. A. Bchal. — On the
presence of methyl salicylate in some native plants, by M. Em.
Bourquclot. — On the formation of new colonies by Termes
lucifugiis, by M. J. POrez. — The defence of the organism against
parasites among insects, by NL I.. Cucnot. — External cliaiacicr-
istics of chyltidio>isof the vine, by M. A. Prunct. — On a myco-
bacterial disease of TrUhohma terreiitii, by M. Paul Vuillemin.
— Defence of " Saharien " as a name for the last geological
period, by M. Mayer-Eymar. — On the presence and distribution
of glycogen in tumours, by M. A. Braull.

Berlin.

Meteorological Society, October 9. — Prof. Ilellmann,
PrcbiJcnt, in the chair. — After the President had dwelt on the
loss sustained by meteorology owing to the death of von Ilelm-
hollz. Dr. Schwalbe spoke of his own endeavours to utilise for
scieniific purposes the curves of temperature obtained from
the " Uranus " pillars. He found am<ng the many meteoro-
logical pillars in Berlin which had given continuous records
during the years 1892 and 1893, very few whose readmgs corre-
sponded with those of control instruments. Taking the month
ol July for each year, he had endeavoured to arrive at the mean
daily temperature by taking the mean of the temperatures regis-
tered every hour of each day in the month. He found this mean

,. , ,^ , , L 6-f2-(- 10

temperature tone between the values ol the expressions - -

and ^"*'*'^ '"*"'.— Dr. Kassner had instituted observations

4
doring ihe year on cloud-waves, to which, since Helmholtz'
researches on the formation o( waves when two layers of air of
different density and travelling with different velocity move
past each other, meteorologists have devoted very special
atlcnliuD. From these it appears that the above form of cloud,
consisting mostly ol cirius and cirrocuniulus, usually causes
deposits. The speaker expressed the wish that thorough and
continuous ol»civation of this phenomenon might be made in
order to leit it.

BOOKS, PAMPHLETS, and SERIALS RECEIVED.

Books. — Imcgral Calculus: J. EUwards (Macmillan).— A Treatise on
Cbcmutry : Sir H. t- Rosto« and C. Sctiorlemmcr, Vol. 1, new
cd lion (Macmillan)— KciM nacti Sudindira : E. Schmidt (LcipiiK,
Engtimann) — Lihibuch der Ptlrograpliic : Dr. F. Zirkcl, Dfiitcr

NO. 1307. VOL. 51]

Band (Lciprie, Engelmann). — Resultatcn dcr Aetzmethodc in der Krys-
tallographi^chcn Forschunc : Dr. H. Baumhauer, Text and Atlas
(Leipzig, EngelmannV — Electric Lighting and Power Distribution: W.
P. Maycock, new edition (Whitiakcr) — Electric Light Installatt ns . Sir
D. Salomons, Vol. %: Application, 7th edition (Whittaker). — Forest Birds,
their Haunth and Habits: H. F. Witherby(K. Paul).— By Order of ihe
SuD to Chile to see his Total Eclipse, April 16. 1893; J. J. Aubertin{K.
Paul). — The V.iccination Question : A. \V. Hutton (Methuen). — Reports
from the Lab^rator>' of the Royal College of Physicians. Edinburgh. Vol. 5
(Edinburgh, Clay). — Dr. William Smellie and his Contemporaries : Dr. J.
Glaister (Glasgow, MacLehose) — The Dawn of Civilisation : G. Maspero,
translated by M. L. McCIure (SP.CK ).— Preparatory Physics : Prof. W.
J. Hopkins (Longmans).

Pamphlets. — The Maya Year: C. Thomas (Washington).— Tableau
Mitrique de Logarithmcs : C. Dumesnil (Paris, H.-^chette). — On Pedal and
Antipedal Triangles : A. S. Ghosh (Calcutta, Patrick Press). — VVei-imannism
once more: H. Spencer (Williams and Norgate). — On the Use of Detached
Coefficients in Elemcntarj' Algebra: J. D. Paul (Bell). — Pearl and chank
Fisheries of the Golf of Slanaar : E. Thurston (Madras). — Die Tempera-
ture: Dr. A. E. Forster (Wicn, Holzel).— Mean Density of the Earth; E.
D. Preston (Washiogton). — Analytischc Theorie der t trganischen Entwick-
elung : H. Driesch (Leip/Ig, Engelmann). — Das Veihahnis der Phtlosophie,
&c. : D Weiterhan (Leipzig, Engelmann). — Gedii:h[nis*eredc auf Hermann
von HelmhoUi : Th. W. Engelmann (Leipzig, Engelmann). — Grundiuge
der Mathematischen Chemie : Dr. G- Helm (Leipzig, Engelmann). — Ver-
handlungcn der Deutschen Zoologischen Gesellschaft *iuf der vierten
JahresversammluDg zu Munchen, den 9, bis 11, April 1S94 (Leipzig, Engel-
mann).

Seriai.5. — Science Progress, November(Scientific Press, Ltd.). — Scien-
tific Roll— Climate ; Baric Condition, No. 6(Castlc Printing and Publishing
Company). — Medical Magazme, November (Southwood) — Zeiischrift fiir
Phvsikalische Chemie, XV. Band. 3 Heft (Leipzig, Engelmann). — Imperial
University, College of Agriculture, Bulletin Vol. a, No. 2 (lokyo)—
Memoirs and Proceedings of the Manchester Literary and Philosophical
Society, Vol. 8, No. 3 (Manchester). — Himmcl und Erdc, November
(Berlin) — .American Journal of Science, November (New Haven). — En-
gineering Magazine, November (Tucker). — Journal of the Sanitary Insti-
tute. October (Stanford). — Portfolios of Photographs: Beautiful Britain.
Art Scr.es. No. 1. (Werner Co.). —Journal of the .Asiatic Society of Bengal,
Vol. Ixiii. Part 2, No. 2 (Calcutta).

CONTENTS. PAGE

Historical Exposition of Mechanics. By Prof. A. G.

Greenhill, K.R.S . 49

Newth's Inorganic Chemistry. By M. M. Paltison

Muir 52

Our Book Shelf:—

Porro : '•Astronomia Sferica. An Elementary Trea-
tise" 53

"The New Technical Educator."— N. J. L 53

Hooker: "Index Kewensis Plantarum Phanerogam-
arum " 54

Ilardwickc : " Alpine Climates for Consumption " . . 54
Letters to the Editor:—

" Acquired Characters."— Prof. E. Ray Lankester,
F.R.S. ; Prof. Edward B. Poulton, F.R.S. ;

Francis Gallon, F.R.S 54

Science Teaching in Schools. — W. B. Crump ; Grace

Heath 56

Italian Scientific Expedition to Monte Rosa. — Dr.

Piero Giacosa 57

Chinese Beliefs about Caves. — Kumagusu Mina-

kata 57

■Spots over Dogs' Eyes.— Worthington G. Smith . 57

Gravitation.— Dr. J. Joly, F.R.S 58

Homogeneity of Siruciure the Source of Crystal

Symmetry.- Wm. Barlow 58

The Present State of Physiological Research ... 58

Ink Crystals. (IlluslraUJ.) 60

Notes 61

Our Astronomical Column : —

.•\ XcA \'ariahlc Star of the Alg>l Type 64

The Polar Caps of Mars 64

l-^ncke's Comet . , .... 64

Statistical Account of French Forests. By Prof.

W. R. Fisher 64

The Properties of Liquid Ethane and Propane. By

A. E. Tution 65

The Britisn Central Africa Protectorate 66

Early British Races. (ilhisliaU.I.) By Dr. J. G.

Garson . • •67

University and Educational Intelligence 70

Scientific Serials 7°

SocieiicR and Academies 7'

Books, Pamphlets, and Serials Received 72

NA TURK

7Z

PSYCHOLOGY OF MEXTAL ARITHMETI.
CIANS AND BLINDFOLD CHESS-PLAYERS.

Psychologie des Grands Calctilateurs et Joiteurs d'Echecs.
Par Alfred Binet. (Paris : Hachette and Cie., 1894.)

WHOEVER may hereafter write about mental im-
agery will be imperfectly equipped for liis task unless
he has mastered the contents of this curious and instruc-
tive volume. It analyses the mental processes of two groups
of remarkable men — those who possess extraordinary
powers of mental arithmetic, and those who are capable
of playing eight or more games of chess, blindfold and
simultaneously. The idea of making the inquiry is due
to the late Prof. Charcot ; its prosecution has been
conducted almost wholly by M. Binet, and principally at
his laboratory in the Sorbonne. The prosecution of such
an inquiry with the accuracy needed by modern rjsycho-
logy is exceedingly difficult, and it is also very difficult
to express such results as may be obtained from it, in
unambiguous language. The author has, however, suc-
ceeded in the latter as well as in the former, and he has
framed many happy turns of expression which will
contribute to the much desired evolution of psychological
language.

The book begins by quoting the series of historical
cases of mental arithmeticians, that was published by
Scripture in iSSi, in the American Journal of Psycho-
logy. They suffice for making useful generalisations,
though few of the cases were tested with much precision.
Then the original work commences. It refers to two
remarkablecalculators, whoare now living, both of about
the age of twenty-six, but whose mental processes entirely
differ in their most obvious characteristics. The one is
Inaudi, a Piedmontese, who performs his mental sums
wholly, or almost wholly, by imagined sounds, one, tiuo,
three, &.z. ; the other is Diamandi, a Greek, who attains
the same end almost wholly by imagined figures, as 1,2,
3, &c. The careful testing of these two men, and the
analyses and comparisons of the results, show the
strange unlikeness of human minds in the above well-
marked features, accompanied, it may be, with a nearer
likeness in those deeper and more obscure qualities,
which are exceedingly difficult to grasp. I, myself, had
the pleasure of testing Inaudi at my own house, in com-
pany with a few scientific friends. Even the small
number of experiments that there was then time to
make, rendered it clear to my own mind that the con-
clusions which had been arrived at, after prolonged and
careful experiments in France, were i.|uite justified,
namely, that he performs his long sums almost wholly by
his auditive imagination, supplemented possibly by the
motive, or gesture sense, but that the visual form of imag-
ination was practically absent during the calculations.
His case is an extremely rare one, and proportionately
valuable for study. On the other hand, Diamandi is an
excellent example of the common type of mental calcu-
lators, who work almost wholly by the visual imagination.
A comparison between the achievements of Inaudi aiid
NO. I30S, VOL. 51]

Diamandi under similar tests, is the main feature of the
first half of Binet's volume. He succeeds in distinctly
negativing the assertion that the visual memory, even of
a man who is so exceptionally gifted in that way as
Diamandi, resembles actual vision either in its accuracy
or in its completeness. Thus if a small square table of
twenty-five figures, five figures in breadth and five in
height, is shown to and learnt by Diamandi, he takes
only nine seconds to repeat them in successive lines,
but if he is asked to repeat them in the order of the
columns, he is just four times as long in doing so, whether
the columns are mentally read from their tops downwards,
or from their bottoms upwards. He does not therefore
read the figures as if they were written on a mental
blackboard, which could be done as easily in any one
direction as in any other, but he has, in some obscure
way, to puzzle the figures out. When another table of
twenty-five figures is taken, in which the figures are
variously coloured, Diamandi's power of re-presenting
colours being about as strong as that of re-presenting
form, he has no difficulty in learning them, but he does
it by two successive operations, first learning the figures
and then the colours, and he is consequently twice as
long over his task. This could hardly be the case if the
visualised schedule had the completeness of an " after-
image " or of a photographic plate.

A great difficulty in the way of testing the power

of the memory of professional calculators is caused by

their habit of accumulating large stores of mnemonic

; helps, which produce results that simulate those of

j a direct memory. It is indeed difficult for any one

to free himself wholly from the use of such helps,

j which arise unbidden, more or less consciously, certain

runs of figures, or accidents of position in the page, being

; more readily fixed in the memory than others. Binet's

chapter on this subject is very instructive.

The most famous calculating boys had their calculating
faculties developed very early in life. Many began to
calculate of their own accord before they could read or
write, and for the most part they were born in humble
circumstances. It is found, so far as present information
goes, that they did not inherit their gifts, except in a few
cases, of which the Bidder family is a conspicuous in-
stance. For my own part, I hesitate for awhile to accept
the above negative result as a fact, and on the following
grounds. Two mental peculiarities have to concur in
the making of a calculating boy : the one is a special
capacity for mental calculation, and the other is a passion
to e.xercise it. Both of these peculiarities are rare, and
they are not necessarily coordinated, therefore the chance
of their concurrence in full force may be very small ir.-
deed. I have, however, reason to suppose that the
capacity for mental calculation is more common than is
usually believed, but that it does not commonly interest its
possessor, and may even be unknown and consequently
neglected by him. Trustworthy evidence for or against
its hereditary transmission could hardly be obtained under
these conditions. I may quote the case of a deceased lady
of remarkable ability, which I indirectly verified to my own
satisfaction at the time. She told me, and her husband
confirms my recollection, that one night, while travelling
I to the south of France, she could not sleep,' so she

E

NA TURE

[November 22, 1S94

amused herself, as is common on such occasions, with
various idle trains of thought. Then it occurred to her
to tr\" mental sums, and finding, much to her surprise,
that she had great facility in doing them, she became
interested and exerted herself to the utmost. Before her
train had reached Lyons, she had successfully multiplied
one series of eleven figures into another series also of
eleven figures. She subsequently trained herself to
multiply fifteen figures into another fifteen. I am
informed that her first attempt at the latter had one
error, and, on being told that it was not correct, she went
over it again mentally and gave the correct result.
Another case comes to my memory. It appears
that there was a craze for mental arithmetic in the
period 1S20-30, or thereabouts. My father was in- j
terested in the subject and made experiments on many
friends and on all his servants, with the result, as I used
to hear, that the best performer of all, and a really re-
markable one, was a somewhat obtuse and uninteresting
servant girl. She took no especial pleasure in calculation,
and on that account would never have made a study of
its processes by herself ; nevertheless, she had the
capacity for using them. An innate passion for arith-
metic, such as all the great calculators possessed, is
certainly uncommon. If only a moderate passion for it
should exist, it is likely to become repressed by circum-
stances, because it is nearly useless to the possessor.
It is difTicult to imagine that anyone who was not
fascinated by figures would devote the best part of
his time and energy to them. Professional calculators
are said to be usually (by no means always) narrow-
minded, and to have their heads filled with mnemonic
contrivances.

I may be permitted to allude to an inquiry analo-
•gous to that which has here been made into the visual
and auditive imaginations, which 1 made on myself,
on a small scale, in respect to the olfactile imagin-
ation. I tried to perform mental arithmetic, not by
imaginary visual symbols, or by imaginary sounds, but
by imaginary smells. As sums are set in the two former
cases, either in really visible symbols or in really audible
sounds, while the results are reached through imaginary
ones, so in my experiment the sums were set in real odours,
and were worked out through imaginary odours. I de-
scribed the result briefly, not many months ago, in the
American Psychological Review, and think the imiuiry
worth repetition, especially by experimenters, who may
possess the power of re-presenting odours to themselves
more vividly than I have. It would enable them to per-
ceive the processes gone through in mental arithmetic
from a new point of view. My apparatus consisted of
glass lubes, each drawn to a nozzle at one end like a short
syringe. One end of a piece of india-rubber tube, six or
eight inches long, was pushed tightly over the other end
of the glass. A different odorous substance, camphor,
carbolic acid, gasolin, &c., was inserted and packed
lightly with cotton wool in the several lubes, whose ends
were afterwards tied up. On grasping one of these tubes
tightly, at the moment when its nozzle was brought to
the nostril, a whiff of its peculiar odour was ejected and
simultaneously sniffed up. This could be rapidly repeated
three or four times without much diminution of the
odour of the whiff. (An arrangement with valves would
NO. 1308, VOL. 51]

have much improved its action, by ensuring that no air
should be ejected that had not passed through the scent.)
I thus possessed a set of tubes that could be used
sincllingly, in the same way as the symbols i, 2, 3, &c.,
are used visually, or the words one, two, three, &c., are
used audibly. This is not the place to enter into further
details. I only desire to emphasise one fact which the
e.xperiment taught me, namely, the existence of a large
substratum of mental work that my power of introspec-
tion failed to penetrate. I progressed far enough to be
able to add or subtract small sums, so that a i followed
by a 2, both in smell language, associated themselves at
once with the imaginary sniff of a 3, whenever I was en-
gaged in addition, or with that of a i when I was engaged
in subtraction. But the two associations of 3 and i
never clashed ; they were mutually exclusive. I could not
ascertain through introspection what was the nature of
the atlitude of tnind which determined whether the
association was to be the one needed for addition or for
subtraction, for division or for multiplication. Another
point that strongly impressed me was the enormous |
amount of labour that must have been gone through [
by all of us in thoroughly learning the multiplication |
table. I made a very few similar experiments with the |
gustatile or taste-imagination, but they were trouble-
some, and I did not follow them up.

There is little room now left to speak of the latter half
of Binet's volume, which refers to the great chess-players,
who play eight or more games blindfold and simul-
taneously. The evidence is overwhelming that the faculty
of visualising is not exercised by them in the same sharp
and distinct way that it is commonly supposed to be
They do not see the chessmen and the complete board all
at once and with clear definition, but they commonly see
all besides the portion they are considering, more or less
vaguely, and they appreciate the positions of the men
as hidden centres of forces. Two letters, which close
the volume, by the distinguished chess-players Goetz and
Tarrasch, seem to me models of exact introspection and
of clear description. Francis Galion.

THE COLLECTED IVORKS OF OLBER^.

Wilhelm Others, sein Leben und seine Werke. Im Auf-
trage der Nachkommen herausgegeben von Ur. C.
Schilling. Erster Band, Gesammelte Werke. xix. +
707 pp. Svo., with portrait. (Berlin, 1894.}

GERMANY has not produced as many amateur
astronomers as England has, but among them the
man whose complete writings have now been published
occupies a most remarkable place. Olbers was an
amateur, but his work was that of a professional as-
tronomer. Though occupied all day in the extensive
practice of a physician, he devoted his nights to search-
ing for comets, making micrometric observations of
these bodies, whether found by himself or others, with
the annular micrometer, an instrument the immense value
of which he was the first to perceive, and computing
their orbits by the simple method devised by him, which
he is said first to have applied practically while watching
at the bedside of a patient. At the top of his house in
the Sandstrasse in Bremen he had his exceedingly

November 22, 1894]

NA TURE

75

modest observatory, at the equipment of which, con-
sisting only of small and portable instruments, any
modern amateur would turn up his nose. For years he
was obliged to correct his clock by tedious observations
of equal altitudes with a sextant and artificial horizon,
until he devised the simpler and quicker method of
watching the disappearance of stars behind a distant
tower. But his labours brought him a plentiful reward,
not only in the discovery of the planets Pallas and Vesta
and various comets, and in the renown which these and
his important publications procured him, but also in the
friendship of Schriiter, Zach, Gauss, Bessel, Schumacher,
Encke and others, who always in their letters and
published writings mention him with the greatest
veneration.

The publications of Olbers are scattered through
many volumes of the various periodicals of his time,
some of which are not readily accessible now-a-days.
But most of them are still of the highest importance,
not only those describing the method which is practic-
ally the only one used for computing cometary orbits,
but also those in which Olbers has deposited the results
i>f his deep study of the literature of comets, ancient
and modern, as well as the many articles which bear
witness to his having possessed mathematical abilities of
no mean order. The appearance of the complete edition
of his works now before us will therefore be hailed with
pleasure by astronomers. It is to be followed by two
other volumes, containing the correspondence of Olbers
with Gauss, and a biography by the editor.

The celebrated and epoch-making memoir on the
most convenient method of computing the orbit of a
comet was printed separately (in 1797), and it naturally
opens the volume now published. After it (and the
appendix published in the Jahrbuch for 1833) the editor
has placed twelve other papers under the common head-
ing " Abhandlungen." It is not easy to see why these
particular papers have been distinguished in this manner.
It is not because they are the longest, for some of them
occupy only a few pages, so it must be because the
editor considers them specially important. But if so,
why are others, fully as important, not put along with
them, as, for instance, the classical paper on the tail of
the great comet of iSi i ? The arrangement of the other
papers in six groups also frequently challenges criticism.
Under the heading " Comets " are given no less than
110 papers, but half a dozen notes on comets are
relegated to the group of " Miscellanea from letters,"
near the end of the book, apparently simply because
they were written in the form of letters to the editors
of various journals. The useful index at the end of the
volume will, however, enable the reader to read these
notes in connection with the other papers on comets.
On the other hand, the papers on the comets of 1802 and
181 1 (pp. 293 and 315) are made up of pieces detached
from two editorial articles in the Monailiche Corre-
spondent, omitting all the observations not made by
Olbers ; and this patchwork might, perhaps, better have
been put among the miscellaneous notes. It would have
been much simpler, and apparently more satisfactory, if
all the papers (except the separately published book of
1797) had been printed in chronological order, as the
index would even then have made it easy to pick out
NO. 1308, VOL. 51]

I

papers on any special matter. It is, however, more to be
regretted that the editor has not seen fit to add some
explanatory notes, which would greatly have increased
the value of the book to young students of astronomy>
who cannot be supposed to be thoroughly acquainted
with its literature. We shall only point out a few cases
where such notes would have been particularly useful.
The first is Olbers' letter to Encke about the mysterious
comet alleged to have been observed by D'Angos at
Malta in 1784, reprinted here from Encke's well known
paper with the startling title, " Imposture astronomique
grossicre du Chevalier D'Angos." We certainly think
that the editor might in a short note have given refer-
ences to the more recent investigations on this matter by
d' Arrest and Gyldc'n, which render it at least very pos-
sible that D'Angos really found and on two nights
observed a comet. At any rate we cannot be certain
that the whole matter was nothing but a fraud, and a
different heading to the article might have been chosen.
On page 226 it should have been pointed out that the
orbit of the comet of 1558 has also been computed by
Hoek (from observations by Pa,ul Fabricius), whose
results differ considerably from those of Olbers. On p.
228, Olbers suggests that the manuscripts of Father
Schall in the Vatican might contain comet observations
from 161S. It would have been useful to have added a
note to the effect that these manuscripts have afterwards
been found not to contain any such observations [Corresp.
Astron. V. p. 143). .Similarly the article on Cacciatore's
supposed planet of 1835 (p. 526) should have been
accompanied by a note referring the reader to the calcu-
lations of Valz and Luther, as well as to Nature, voL
xviii. p. 260, which might prevent some rash student
from wasting his time on this object.

The papers have been reprinted from the originals
without any alterations, so that even errors pointed out
in subsequent papers have been allowed to stand {c.i;. pp.
523 and 53S, compare pp. 649 and 542). Some papers
will be quite new to most readers, as they were published
in journals of limited circulation, such as Harding's
Kleine Ephemeriden, Gottingische Anzeigen, and Gruit-
huisen's Analekten and his Jahrbuch. The charming
character of Olbers is seen in his notes to Gruithuisen,
in which he frequently gently corrects mistakes in the
writings of this enthusiastic but somewhat erratic ob-
server. In an appendix are given two papers of 1787
and 178S on mesmerism. Olbers' dissertation for the
decree of M.D. (De oculi mutationibus internis, Got-
tingen 1780) is not reprinted.

The book is well printed, and has as frontispiece an
excellent portrait of Olbers. In addition to a table of
contents and an index, it contains a list of all the papers,
arranged according to the journals in which they first
appeared. No mention is here made of the catalogue
of cometary orbits (published in Schumacher's Ahhattd-
liingcn) ; but this has not been reprinted, and is of course
long ago superseded.

In laying aside this splendid volume, we cannot refrain
from making one more remark. We have now the
collected works of Laplace, Gauss, Bessel, Encke,
Olbers ; how long are we to wait for a complete edition
of the works of William Herschel ?

J. L. E. D.

NATURE

[November 22, 1894

QUA TERN IONS.
Anwciidiing dcr Ouitternionen auf die Geometric. \on

Dr. P. Molenbroek. (Leyden : E. J. Brill, 1S93.)
The Outlines of Quaternions. By Lieut. -Colonel

H. W. L. Hime. (London: Longmans, Green, and

Co., 1S94.)

IN these books we have evidence of the growing 'de-
mand for quaternion literature. Dr. Molenbroek's
work is the promised sequel to his first volume on the
Theory of < Quaternions, and contains many admirable
e.>camples of the application of the method to geometry.
.•Ul who are familiar with Hamilton's and Tait's classics
on the subject will recognise many of these examples as
old friends, taken almost verbatim from their original
sources. In not a few of the applications, however, Ur.
Molenbroek ventures into fresh fields, and shows that he
can use quaternions with ease and power. It is interest-
ing to notice the occasional eti'ective use of the conjugate
quaternion, an invention of the great master which is
apt to be lost sight of after the foundations of the
calculus have been laid. The treatment throughout is
on the familiar Hamiltonian lines, the author's aim being
development and not fancied improvements. The book
consists of six chapters, in which are taken up — to name
a few of the most important applications — spherical
trigonometry, the plane and sphere, quadric surfaces,
surfaces in general, curves in space, and the theory of
rectilinear rays. The elementary properties of the
remarkable operator V> and 'he integration of partial
differential equations of the first and second orders, are
discussed as part of the general theory of surfaces. In
the same chapter. Dr. Molenbroek, by means of two new
differentiating operators, obtains a simple symbolic re-
presentation for the first, second, and higher polars of a
point with regard to a given surface. These remarks
will indicate sufficiently the scope of a work which,
though not altogether above criticism in minor details,
is a distinct addition to quaternion literature, and
deserves a wide circulation.

Colonel Hime's work is a much more modest produc-
tion; being intended for the mere beginner. In general
scope it might be compared to the first nine chapters of
Kelland and Tait's " Introduction to Quaternions. ' The
book contains many good examples in the simpler applica-
tions of quaternions to the geometry of triangle, plane,
sphere, conic section, cone, Ovc, but it is less satisfactory in
the exposition of the fundamental principles of the cal-
culus. For example, the identification of unit vector and
right versor is stated, but the reason for this identification
is nowhere distinctly given. Again, the truth that the
familiar Hamiltonian symbols /' j k may be regarded as
in a sense im.ti^iitaries, because i- = J- = k- — — I, is
supposed to lead to the equation
i=j = k = \/ - I = - i = -j= - k (Eq. 8, p. 40).
This seems to be playing sad havoc with one's very
definitions. Then on page 76 we find what is virtually
the equation Aji 'd = y transformed into (i- — y^, the
non-commutative principle being wholly ignored, and in
consequence a quaternion and a scalar equated ! These
errors, especially the latter, are very surprising in a book
whose author is a true disciple of Hamilton. Of minor
blemishes we might refer to the appeal to Cartesian
NO. 1308, VOL. 51]

expansions in order to demonstrate (?) the associative
principle in multiplication. Xor do we quite understand
Colonel Hime's system of referring to authorities. For
example, why should Prof. Hardy be quoted as the
authority for the statement that every versor may be
represented by a power of a unit vector : for is it not all
in Hamilton (see " Ele.nents,'' § 309) .' .Again, Dr. ()dstrcil
is credited with a proof that the three angles of a plane
triangle are together equal to two right angles, the proof
being an obvious particular case of Hamilton's remark-
able expression for the product of the versor arcs of a
spherical triangle. But surely the theorem regarding the
angles of a plane triangle underlies the fundamental
properties of quaternions and versors ; so that the sup-
posed proof is really reasoning in a circle. Dr. Odstrcil
is worthy of higher praise than this. These blemishes
apart, however, and leaving out of account the two errors
already noted, we find in Colonel Himes book a ser-
viceable exposition of the elementary applications of
quaternions. A careful study of its pages will go far to fit
the reader for the arduous task of grappling with the
higher and more characteristic developments to be found
in the writings of the masters of the quaternion calculus.

OUR BOOK SHELF.

Sir Victor Brooke, Sportsman and Naturalist. By O.

L. Stephen. (London: John Murray, 1S94.)
The late Sir Victor Brooke was an excellent example
of a combination of sportsman and naturalist. In this
book his life as a sportsman predominates; but a chapter
on his researches in natural history, by Sir William
Flower, shows that he possessed the keenness of
observation required in a man of science. His most
important contribution to science was an exhaustive
paper, published in the Proceedings of the Zoological
.Society, the subject being the classification of the
Cen'ida:. At one time he was an enthusiastic student
of natural history, but the state of Lady Brooke's
health having compelled him to live out of England
for the greater part of the year, he could not con-
veniently carry on his researches. From about iSSo
his life was chiefly devoted to foreign travel and sport.
The extracts from his letters and journals are full
of stirring adventures, and contain some interesting
observations on animal life and habits. Mr. Stephen
prefaces these extracts with a memoir of his dead friend.
The book is beautifully printed, and is illustrated by
ten fine plates. It appeals particularly to those who
were acquainted with Sir Victor Brooke, and who ad-
mired his character ; nevertheless, such of the public
as read it will find the contents interesting.

A Text-book 0/ Dynamics. A Text-liook of Statics. By
William Briggs and G. H. Bryan. (The University
Tutorial Series.) (London: W. B. Clive, 1894.)
These books belong to the elementary class, and a
perusal of them shows that they will prove excellent
additions to this series of useful text-books.

In both the authors have assumed little or no know-
ledge of trigonometry, and they have been written
so that either may be read first. The treatment is con-
spicuous for its clearness and conciseness, and is all that
a student about to enter a course could desire. The
figures are neatly drawn, and many new ones are
noticeable in the latter book.

Notwithstanding the fact that these text-books are
published to meet the requirements of candidates for
certain examinations, they may still be used by others,
who are making themselves acquainted with these sub-

November 22, 1894]

NA TURE

77

jects. Besides several excellent series of examples,
a very useful summary is added to each chapter,
which will be serviceable for revision purposes. The
adoption of different sizes and kinds of type, when it is,
as here, carefully done, is also a very great boon to
beginners.

The Sliiie-Rule. A Practical Manual. By Charles X.

Pickworth, Wh.Sc. (London : Emmott and Co., Ltd.,

1894.)
The most modern form of slide-rule is of the Mannheim
or Tavernier-Gravct type, and undoubtedly surpasses its
predecessors in many ways. At the present time this
instrument is in general use on the continent, principally
in France and Germany, and it is now becoming more
popular in England.

The slide-rule may be defined as an instrument for
mechanically effecting calculations by logarithmic com-
putation. By its aid arithmetical, algebraical, and
trignometrical processes may be performed much
more quickly and with greater ease than by the
ordinary methods, while the accuracy of the results
are quite within the limits of error for all practical
purposes. There is no doubt that when the instrument
is better known, and its labour-saving property recog-
nised, it will be more commonly seen in the laboratory
and workshop than it is now. So many manipulations
can be done with it that, without some guide, its full value
cannot be appreciated. In the present little manual
the author brings these all together, and in such a form
that the reader can, by paying attention to the mechanical
and mathematical principles, obtain an intelligent interest
in the manipulations, and have confidence in the results.

W. J. L.

/ Fondainenii Matematici per la Critica dei Risullali
Speriiitenlali. Del Prof. P. Pizzetti. (Genova, 1892.)

An elaborate memoir, of the nature of a complete treatise
on the Method of Least Squares, in its application to the
reduction to order of a long-continued series of experi-
ments and of their numerical results.

It contains a valuable bibliography of writings on the
subject, arranged alphabetically according to authors'
names.

Hitherto the astronomer has made most use of this
theory ; but the artillerist is now finding it important for
his purposes, in calculating from the number of hits to
effect a desired amount of destruction the amount of
ammunition required. G.

Teppich-crzeuffung tin Orient. By various Contributors
Pp. 204. (W'len : K. K. Osterr.Handels-Museum,
1895.)

Thls work consists of a series of monographs on im-
portant antique tapestries contained in European
museums and private collections, contributed by Sir
George liirdwood, Mr. C. Purdon-Clarke, .Mr. Vincent J.
Robinson, Mr. S. J. A. Churchill, Dr. W. Bode, M.
Gerspach, and M. O. M. Stoeckel. In addition to the
history of antique tapestries, the work contains descrip-
tions of a number of the more important types of modern
tapestries of the Levant, Persia, and India. The illustra-
tions are numerous and of high quality.

A Laboratory Manual. By \V. R. Orndorff, A.B., Ph.D.
(Boston : D. C. Heath. London : Isbisier and Co.,
1894.,

A COURSI': of experiments in organic chemistry, system-
atically arranged as an adjunct to Prof. Ira Remsen's
work on the " Compounds of Carbon." As Dr. Orndorff
has had a large experience in the laboratory work to
which the book refers, the conditions of the experiments
described can be depended upon, which is the highest re-
commendation that can be given to a manual of this kind.

NO. r -^08, VOL. 5 1]

LETTERS TO THE EDITOR.

The Editor docs not hold himself responsible for opinions ex-
tressed by his correspondents. Neither can he undertake
to return, or to correspond zvilh the writers oj, rejectee
manuscripts intended for this or any other part o/ifATVRK.
No notice is taken of anonymous communications. ]

Finger-Prints.

I HAVE been quite unable, since I saw Mr. Faulds' letter in
your issue of October 4, to take the matter of it in hand hithet to ;
and I do so now only because I think Mr. P'aulds is entitled to
raise the question if he pleases. To the best of my knowledge,
Mr. Faulds' letter of 18S0 was, what he says it was, the first
notice in the public papers, in your columns, of the value of
finger-prints for the purpose of identification. His statement
that he came upon it independently in 1879 (? 1S78) commands
acceptance as a matter of course. At the same time I scarcely
think that such short experience as that justified his announcing
that the finger-furrows were " for-ever unchanging."

How I chanced upon the thing myself in 1858, and followed it
up afterward?, has been very kindly slated on my authority by
^Ir. Gallon, at whose disposal I gladly placed all my materials
on his request. Those published by him are only a part of what
were available. (See his "Finger-Prints," page 27, and his
" Blurred Finger-Prints.") To what is there stated I need now
only .add, at -Mr. Faulds' request, a copy of the demi-official
letter which I addressed in 1877 to the then Inspector-General
of Jails in Bengal. That the reply I received appeared to me
altogether discouraging was simply the result of my very
depressed state of health at the time. The position into which
the subject has now been lifted is therefore wholly due to Mr.
Gallon through his large development of the study, and his
exquisite and costly methods of demonstrating in print the many
new and important conclusions he has reached.

I take the opportunity, in reference to a late article on An-
thropometry (in the A'ineteeiith Century of September 1894,
p. 365), to deprecate, as being to the best of my knowledge
wholly unproved, the assertion that the use of finger-marks m
this way was "originally invented by the Chinese." I have
met no evidence which goes anywhere near substantiating this.
As a matter of fact, I exhibited ihe system to many passengers
and officers of the P. and O. steamship Moii^'olia in the Indian
Ocean, during her outward voyage in February 1S77 ; and I
have the finger-prints of her captain, and of all those persons,
with their names. It is likely enough that the idea, which
caught on rapidly among the passengers, may have found a
settlement in some Chinese pott by this route, and have there
taken a practical form ; but whether that be so or not, I must
protest against the vague claim made on behalf of the Chinese,
until satisfactory evidence of antiquity is produced.

Littlemore, November 7. \V. J. Herschel.

(Trie Copy of Office Corv. )

Hooghly, Au^ist 15, 1877.

Mv De.ar B . — I enclose a paper which looks unusual,

but which I hope has some value. It exhibits a method of
identification of persons, which, with ordinary care in execution,
and with judicial care in the scrutiny, is, I can now say, for all
practical purposes far more infallible than photography. It
consists in taking a seal-like impression, in common seal ink, of
the markings on the skin of the two forefingers of the right
hand (these two being taken for convenience only).

I am able to say that these marks do not ( bar accidents)
change in the course often or fifteen years so much as to affect
the utility of the test.

The process of taking the impression is hardly more difticult
than that of making a fair stamp of an office seal. I have been
trying it in the Jail and in Ihe Registering Office and among
pensioners here for some months past. I have purposely taken
no particular pains in explaining the process, beyond once
showing how it is done, and once or twice visiting the office, in-
specting the signatures, and asking the omlah ' to be a little
more careful. The articles necessary are such as the a'a/Zari-
can prepare on a mere verbal explanation.

Every person who now registers a document at Hooghly has
to sign his "sign-manual." None has offered the smallest ob-
jection, and I believe that the practice, if generally adopted,
will put an end to all attempts at personation.

' Clerks. 2 Man in charge of stattODcr)'.

78

NATURE

[November 22, 1894

The cogency of the evidence is admitted by every one who
takes the trouble to compare a few signatures together, and to
try making a few himself. I have taken thousands now in the
course of the last twenty years, and (bar smudges and accidents,
which are rarely bad enough to be fatal) I am prepared to
answer for the identity of every person whose " sign-manual"
I can now produce if 1 am confronted with him.

As an instance of the value of the thing, I might suggest that
if Roger Tichborne had given his "sign-manual" on entering
the Army on any register, the whole Orton case would have
been knocked on the head in ten minutes by requiring Orton to
make his sign-manual alongside it for comparison.

I send this specimen to you because I believe that identifica-
tion is by no means the unnecessary thing in jails which one
might presume it should be. I don'l think 1 need dilate on
that point. Here is the means of verifying the identity of every
man in jail with the man sentenced by the court, at any moment,
day or night. Call the number up and make him sign. If it is
he, it is he ; if not, he is exposed on the spot. Is No. 1302
really dead, and is that his corpse or a sham one? The corpse
has two fingers that will answer the question at once. Is this
man brought into jail the real Simon Pure sentenced by the
magistrate ? The sign-manual on the back of the magistrate's
warrant is there to testify, &c.

For uses in other departments and transactions, especially
among illiterate people, it is available with such ease that I
quite think its general use would be a substantial contribution
towards public morality. Now that it is pretty well known
here, I do not believe the man lives who would dare to attempt
personation before the registrar here. The mitkhttars ' all
know the potency of the evidence too well.

Will you kindly give the matter a little patient attention, and
then let me ask whether you would let me try it in other jails?

The impressions will, I doubt not, explain themselves to you
without more words. I will say that perhaps in a small pro-
portion of the cases that might come to question the study of
the seals by an expert might be advisable, but that in most
cases any man of judgment giving his attention to it cannot fail
to pronounce right. I have never seen any two signatures
about which I remained in doubt after sufficient care.

Kindly keep the specimens carefully.

Yours sincerely,

\V. IlERSCHEL.

Boltzmann's Minimum Function.

Mr. CrLVEKWELi., in his letter to Nature of October 25,
questions the existence of Boltzmann's minimum function, and
asks will somebody tell us what the 1 1 theorem really proves?

As I have made use of the theorem on several occasions, I
may be permitted to say a word in its defence. I will en-
deavour to answer Mr. Culverwell's question what the theorem
proves for the simple case of equal elastic spheres. If I can do
thai, it will probably not be dilTicuU to generalise the result.

Let then V, or OC in the figure, denote the velocity of the
common centre of gravity of two ehastic spheres, each having
diameter c Let k be their half relative velocity. If we de-
scribe a ipherical surface with radius K about centre C, and if
P/ be any diameter of it, the actual velocities of two spheres
are OP and O/.

L;t the number per unit of volume of spheres whose velocities
arc represented by lines drawn from O to points wiihin the clement
of surface i/S at P be denoted by l'"(/.S. I^ct///S denote Ihc cor-
responding number fur the element i/.S at p. Then l-yi/S is the
number of pairs whose relative velocity K falls within the cone
I Alforneys,

NO. I30S, VOL. 51]

described with solid angle (/S about PC/* as axis. Let P'C^'
be any other diameter, and let FVS', f'J?> be the cor-
responding number of spheres with velocities OP' and 0/>'.

If a pair of spheres collide the relative velocity assumes, as
the result of collision, a new position only, and what that
position shall be depends on the coordinates of the collision,
i.<. the point in which a line parallel to the relative velocity
through the centre of one sphere cuts a circular area of radius
c, drawn through the centre of the other sphere at right angles
to that line. If the collision coordinates be taken at random,
then the following condition holds, viz. : — For any given direc-
tion of R before collision, all directions after collision are equally
probable. Call that condition A.

Now assume condition A to be fulfilled, and consider all
collisions which take pl.ice between pairs of the V R spheres.

The number which after the collisions belong to the class

F/i/S will be on the above assumption '11 Fy</S'.

A-' J J
But before the collisions it is Fy;/S. Therefore, as the result

of collisions it is increased by (/S

://(Fy.

'7f: - A

4ir /

That is

constant.
Therefore

F/)rfS', F/" being treated in the integration as

and if

dt 4ir

_ ir^R
4'

H = /"j>log/-i),/S,

j j'dsfjiF'J-- F/)Iog(F/)rfS'

f IjjdSdSWf - F/01og(F/)

= '"■15 f 1' f fdSJS'(F/ - F'f) log ¥'/ by symmetry

= 4 ''"^ ( /"{Fy - F/) log ^.'/S./S',
4'r J J r /

which is necessarily negative if not zero. The above is true
for all values of V and R, and therefore for the whole system.

Thus we have proved that if condition A be satisfied, then if
all directions of the relative velocity for given V are not now
equally likely, the effect of collisions is to make H diminish.

The objection that I understand to be made is that if you
reverse all the velocities after collisions, the system will retrace
its course with 11 increasing — which is supposed to be contrary
to the thing proved.

The objection is wrong because in your reverse motion con-
dition A is not fulfilled. The proof (is not wrong but) ceases
to be applicable by failure of the condition on which it is based.

Somebody may perhaps say that by this explanation I save the
mathematics only by sacrificing the importance of the theorem,
because I must (it will be said) .admit that tliere are, after all,
as many cases in which H incre.ises as in which it diminishes.
I think the answer to this would be that any actual material
system receives disturbances from without, the cflect of which,
coming at haphazard, is to produce that very distribution of
coordinates which is required to make II diminish. So there
is a general tendency for II to diminish, although it may con-
ceivably increase in particular cases. Just as in matters
political, change for the belter is possible, but the tendency is for
all change to be from bad to worse. S. H. BURBURV.

I New .Square, Lincoln's Inn, November 12.

The Kinetic Theory of Gases.
I CANNOT quite agree in Mr. Bryan's remembrance of what
took place in the discussion of the Thermodynamics Report at
Oxford. As far as I recollect, Prof. Boltzmann's reply wits
not in special reference to such a point .as the specific heats of
gases, but was in answer to a very vigorous, if somewhat
general, onslaught of Prof Fitzgerald, who sim|)ly stated that
It appeared evident from the spectra of gases and other con-
siderations, that the energy could not be e(|ually divided among
all the degrees of freedom of the coirdinates, and said what he
w.intcd to know from Prof. Boltzmann was w/un the thtoiy

November 22, 1S94]

NATURE

79

became iuappUcabU, what assumptions became invalid? — why,
if Dr. Watson's method of generalised coordinates were valid,
the ether, the solar system and the universe generally were not
subject to the Maxwell-Boltzmann law, so that the mean kinetic
energy of every coordinate in the universe should be the same
and so on, insisting that what he wanted to know was w!iy the
theory failed, what assumptions were invalid.

After the other speakers had concluded, Prof. Boltrmann
arose to reply, and he took up a perfectly logical position. He
said that the theory as it left his hands was a mathematical
theorem, a piece of pure mathematics, and that it was for
physiiisls to say how far it applied to gases — that the reason of
any disagreement between the theory and the facts was "a
mystery, as Lord Salisbury had said."

That appears an unassailable position, and the only mis-
apprehension which, so far as I can see, could arise, would be
that Boltzniann had admitted not only that his work was a piece
of pure mathematics, but that it was nothing; more, a bare
theorem without the promise that future adaptations would lead
to an even closer accord between the theory and the facts. If
such an impression as that has got abroad, Mr. Bryan has done
good service in calling attention to the matter.

There seem many difficulties about the suggestion (made by
Dr. I. armor at Oxford, and referred to by Mr. Bryan in his
letter) that the spectra of gases need not be explained by the
Boltzmann law, as they arise not from molecular but from
ethereal vibrations set up by the molecules. Surely if so, the
molecules cannot be regarded as an independent system, and
Dr. Watson's generalised coordinates must include ethereal co-
"rtlinates also, and the Maxwell-Boltzmann law must be
^apposed to hold for matter and ether alike, which does not
lOem to get over the difficulty.

November lo. Edwd. P. Cui-Verwell.

Homogeneity of Structure the Source of Crystal
Symmetry.

Mr. Barlow's letter on this subject (p. 58) raises a problem
of considerable interest, which may be stated in simple words.

He has inquired in the most general manner possible how
anything can be uniformly distributed in space so as to con-
stitute a homogeneous system ; the word homogeneous may be
taken lo signify that round any one member of the system the
distribution of the remainder is the same as round any other.
It is not necessary to say that the units of which the system
consists are figures or solids, but merely that, whatever the unit
may be, it is homogeneously repeated.

Now repetition may conceivably take place by sliding the
unit from one position to another, by rotating it about an axis,
by reflecting it across a plane, or by a combination of these pro-
cesses ; in other \>ords, by translation, rotation, and inversion.
If the last process be excluded, we cannot arrive at all the types
of symmetry presented by crystals ; if it be included, we obtain
all those types and no others. Therefore the crystal structure
is one in which this process is operative. Mr. Barlow himself
does not include inveision as a mode of homogeneity, but
regards it as an additional property possessed by some
crystal structures. Earlier writers have specialised the
problem by taking a particular unit. Bravais and Sohncke,
for example, to whom the modern treatment of the subject is
entirely due, have investigated systems of points. Now the re-
flection of a point is an identical point, so that it is useless to
introduce the principle of reflection or inversion as distinct from
translation in order to derive any one point of such a regular
system from another. The same is true of spheres and many
symmetrical fi;;;ures, and unfortunately molecules have usually
in such investigations been treated as points or spheres or
symmetrical figures.

Mr. Barlow does not consider that his solution of the
geometrical problem supplies a theory of crystal structure or
settles the question whether the seat of the symmetry is in the
arrangement or in the configuration of the molecules.

But it appears to me that a step of very great importance has
been made, for, surely, these investigations prove that the
symmetry of such a structure can be entirely explained by the
arrangement of the unit?. I would go farther, and a^k whether
the result does not suggest that the units which determine the
symmetry of a crysial are units capable of repetition by the
processes of translation, rotation, and inversion. If this be so,
we are not justified in treating them generally as points or as
symmetrical figures.

Many things besides unsymmetrical figures can be conceived
which are capable of such repetitions ; for example, a solenoid,
a vortex motion, a system of forces in statical equilibrium.

I would add that Mr. Barlow's investigation cannot be said
either to support or to contradict the theories of Fedorow and
Schunflies ; it is, as he remarks, purely geometrical, and in this
respect is identical with their researches, and leads to the same
results. It is true that Fedorow has proposed a theory of
crystal structure, but this is only an application of the
geometrical principles which he had previously established.

H. A. MiERS.

British Museum (Natural History), November 19.

Gravitation.

I REGRET that I cannot agree with Dr. Joly's suggestion
(vide p. 57 supra) that the curious adhesion which I observed
between solids immersed in a stretched liquid, lends itself to
any explanation of gravitation on the lines that he indicates.
The phenomenon is, and was described by me as, one of
adhesion, and not, as Dr. Joly puts it, of attrac/ion, for there
was no evidence of any approach of bodies separated by a
measurable thickness of liquid, and there is, further, no reason
to suppose that the phenomenon would occur unless the medium
were already modified in the neighbourhood of the solid sur-
faces, i.e. unless a condition which we may provisionally ascribe
to gravitation already e.xisted. For this reason Dr. Joly's
suggestion appears to me to be an invitation to argue in a
circle.

If there were evidence, which there is not, that the ether
round celestial bodies was modified to a great distance, the sug-
gestion would, I think, be legitimate, but it would then be
necessary to explain the modification.

Devonport, November 18. A. M. Worthington.

The Foucault Pendulum Experiment.

Prof. Greenhill gives currency to quite an erroneous idea
in last week's Nature (p. 50). He says " in the Foucault
experiment of the pendulum which shows the rotation of the
earth, the slightest current of air will destroy and reverse the
desired motion ; so that it is advisable in showing the experi-
ment to have an elastic ball concealed in the palm of the hand,
which can send a slight current of air on the bob of the pendulum ,
and thus accelerate the initial precession of the plane of the
vibration so as to gratify the eyes of the audience and diminish
their impatience at the slowness of the motion." If Prof.
Greenhill will go to the Western Galleries of the South Iven-
sington Museum any day, he will be able to see a Foucault
pendulum fulfilling its purpose without being particularly pro-
tected from draughts, and without the accessory pufts to which
he refers. The pendulum is suspended in a place where people
are continually passing to and fro, yet its plane of vibration
always rotates in the same direction as watch-hands, or rather
the table under the pendulum turns in the opposite direction.
I have watched the pendulum dozens of times without seeing
it Tail. G. A. R.

November 19.

An Observation on Moths.

An experiment was tried in 1S94, on a number of pupa: of
Samia promethea and .Samia cecropia, which brought out a point
of which I have seen no mention. When the moth is almost
ready lo burst through the thin shell which encloses it, this
outer skin becomes dark-coloured and friable, and the insect can
often be seen moving wiihin.

If the enclosing envelope is then removed with a scalpel and
forceps, the moth struggles out, apparently as lively as when
legitimately hatched.

The only hitch in the proceedings seems to be in the non-
expansion of the wings, the development of which usually lakes
place at once. The moth crawls about, like a forlorn penguin,
for a period varying from one to three days, when the wings
seem to realise the absurd state of affairs, and make a brave
effort to fulfil their part of the contract. The effort, however,
is only partially successful, for owing to their dry condition the
expansion is irregular and incomplete, and the poor moth
remains a helpless cripple.

This would seem lo demonstrate that the wings do not mature
as rapidly as the test of the body, and that until complete
maturity is reached, no eflbrt towards expansion is made.

L. C Jones.

N<^. 1308, VOL. 51]

8o

NATURE

[November 22, 1894

PHOTOGRAPHS OF A TUMBU.\G CAT.

MMAREY'S recent photographs of a falling cat,
. taken with the view of determining the mechanical
conditions which enable the animal to alight on its feet,

The former gives a side view of pussy, and the latter
a back view. The cat was held by its feet, and was
let go in that position. In each of the pairs of figures,
the series of images runs from right to left, and the lower
is a continuation of the upper. The expression of offended

h-trWn'n

Fig, I. — Side view of a falling cat. (The series runs from right to left.)

Fig. 3.— Eni view of u falling cat. (I'he series rant from rii;ht to left.)

have excited considerable interest. Figs, i and 2 accom-
panied his paper on the tumbling of cats, presented to
the Paris Academy, and are reproduced in La Nature,

NO. 1308, VOL. 51]

dignity shown by the cat at the end of the first series
indicates a want of interest in scientific investigation.
The rotation of the fore and hind parts of the cat's

November 22, 1894]

NATURE

61

body takes place at different stages. At first the twist is
almost exclusively confined to the fore part, but when this
amounts to about iSo degrees the rear part of the animal
turns. M. Marey is of the opinion that an inspection of
the figures altogether excludes the idea that the animal
uses the hands that let it go as a fulcrum by means of
which a movement of rotation is obtained. The first few
images in each of the two series show that at the begin-
ning of the fall the cat exhibits no tendency to turn
either one side or the other.

As to the hypothesis that the resistance of the air
affords a means of turning, this also appears to be inad-
missible ; because, on account of the tumbling motion
of the animal, if this resistance had an appreciable
effect, it would produce a rotation in the opposite direc-
tion to that observed.

M. Marey thinks that it is the inertia of its own mass
that the cat uses to right itself. The torsion couple
which produces the action of the muscles of the vertebra
acts at first on the forelegs, which have a very small
motion of inertia on account of the front feet being fore-
shortened and pressed against the neck. The hind legs,
however, being stretched out and almost perpendicular
to the axis of the body, possesses a moment of inertia
which opposes motion in the opposite direction to that
which the torsion couple tends to produce. In the second
phase of the action, the attitude of the feet is reversed,
and it is the inertia of the forepart that furnishes a
fulcrum for the rotation of the rear.

BIOLOGY IN THE UNITED STATES— A
PROSPECT}

'T^HIS volume is slightly larger than its predecessor
•'■ published in 1S91, and is an advance upon it in
the number and class of its illustrations. During the
interval of publication of the two volumes, much of the
work announced in the first one has appeared in full ;
and the present one shows that although, perhaps,
more might be made of the resources of the Wood's
Holl Laboratory and its rich surroundings by a better
appreciation on the part of the scientific public, there
is no falling off in either the energy or enthusiasm of its
founders and chief supporters. The ten lectures reported
in this volume are chiefly special ones, given by investi-
gators who undertake to review their chosen field of
labour, and to set forth the results of their own inquiry
— it being an avowed object to bring forward unsettled
problems of the day, and discuss them freely. The
lectures are published for the first time, with the exception
of that which is the most striking of the series and one
of the most remarkable contributions to recent biological
literature, viz. Prof. C. O. Whitman's thesis on " The
Inadequacy of the Cell-theory of Development,"originally
read before the Zoological Congress of the World's
Columbian Exposition, and already reprinted in the
Journal of Morphology. Prof. Whitman's work in this
department dates from his inaugural dissertation for the
degree of Doctor of Philosophy in the University of
Leipzig, dealing with the embryology of Clepsine, in
which he laid the foundation of his now famous telo-
blast theory. The researches which this essay has
provoked rank foremost in interest among all those
recently devoted to the study of the germinal blastemata.
No one has more assiduously followed up Prof. Whit-
man s suggestive lines than Prof. E. B. Wilson, whose
lecture on '• The Mosaic Theory of Development " ranks
first in order in the present volume. His recent work on
the cell-lineage of Nereis is second only to that of Whit-
man in interest and importance. His present treatise

'* Biological Leclures delivered at the Marine Biological Laboratory of
Wood's Holl." Vol. li. (Boston: l'..nn and Co., 1894 )

NO. 1308. VOL. 51]

is a review of the embryological work of the last decade
in its bearing upon the biogenetic law. Prof. Whitman
would seek the secret of organisation in ultimate elements
of living matter "for which idiosovics seems an appro-
priate name " ; Prof. Wilson, that of differentiation
during development in the interaction of the embryo-cells.
There next follows a lecture by Dr. E. G. Conklin, on
"The Fertilisation of the Ovum," apropos of the author's
researches into the development of the marine gas-
teropod Crcpidula plana.

Lecture iii. is by Prof. Jacques Loeb, " On some
Facts and Principles of Physiological Morphology.''
He first considers the question of "heteromor-
phosis" or substitution of organs, as illustrated (under
the maltreatment of Antennularia') by the develop-
ment of new roots and apices in relation to gravi-
tation, and by root formation at points of contact
with solid bodies, in Margeliss and other hydroids. He
shows that it is possible to obtain roots and polyps at
will over various and interchangeable areas, in direct
response to modified conditions of growth. There fol-
lows this a lecture by Prof. Ryder on " Dynamics
in Evolution," which is suggestive but imaginary.
New terms and statements of probabilities it does
contain, but new facts it does not. Its most interest-
ing portions are those relating to surface tension in
its probable bearings on protoplasmic activity ; but it
appears to us rather more sensational than sound. The
comparison of the behaviour of a contracted smoke-ring
to an amccba in motion is suggestive, perhaps in a sense
not intended by the author. Dr. Watasu follows with a
dissertation " On the Nature of Cell Organisation."

Lecture vii. is a very welcome one, by Dr. Howard
.■\yers, on Bdellostoma Dombeyi, apropos of its author's
work upon the comparative morphology and physiology
of the vertebrate ear. He deals at some length with the
habits of the animal, and adduces additional evidence
for the belief in the primitive, as distinguished from the
alleged "by parasitism degenerate" nature of the
cyclostomi which has been so generally accepted.
He records the fact that the gills vary in number from
eleven to thirteen on either side, in individuals from
diflerent localities ; he regards this variation as in-
dicative of suppression, and the numerically highest
as the most primitive type, instituting comparisons
with the larval AmpJiioxus which appear to us
unsound. We welcome his conclusion that the numerical
variation of the gills has nothing to do with the forma-
tion of the ductors cesophago-cutaneus. He pro-
visionally argues that Bdellostoma is unique in the
fact that geographical distribution has had little or
no effect upon its anatomical structure ; and proposes to
recognise but a single genus and species of this form, in a
manner curiously mindful of his notorious attempt to
similarly unite Protopterus and Lepidosircn. Not even
allowing for the possibility that the hitherto ac-
cepted species of Bdellostomas may be distinct in their
habits as well as taxonomically, this proposal ap-
pears to us premature, and systematic ichthyo-
logists will certainly not acquiesce to it. In common
with most subsequent investigators, he finds himself
unable to confirm Beard's alleged discovery of calcified
teeth in these creatures. He regards Beard's '' bone ' as
" much hardened horn, produced by the methods used in
preparation.' This we cannot accept. The cells of
Beard s " calcified teeth," although uncalcified, are
mesoblastic, and the structure described by him as an
" enamel cap " (whatever it may be) certainly does appear
in individual sections. He finds that hermaphrodites
occur even among old individuals ; but while examples
possessed of ripe ova and spermatozoa may be forth-
coming, he finds them to be rare, and concludes
that preponderance of males is the ordinary con-
dition. His observations upon the olfactory organ

S2

NATURE

[November 22, 1894

have led him to the belief in the paired nature of the
cyclostome nose, but they are curiously at variance with
those of Von Kupffer that have lately led to the opposite
conclusion. His remarks upon the functions of the
thread-forming type of cutaneous gland are particularly
welcome, in correlation with Weymouth Reid's work
upon the origin and constitution of the thread substance.
Concerning the ear, he records the striking result that
while removal of one labyrinth leads to marked disturb-
ances in the equilibrative function, on the removal of
both ears all trace of such disturbance disappears.
Morphologists and physiologists will await with interest
the full edition of this important communication.

Lectures viii. and ix. are botanical, and as unequal in
merit as any two in the whole work. One of them, by
Prof. Muirhead Macfarlane, on " Irrito-contractility in
Plants," is a record of some beautiful and striking experi-
ments, a very charming one being that with a block of
ice, from which he has drawn the conclusion that
displacement of the Oxalis leaf under its action is the
etTect of cold and not of weight. The author
reverts to his earlier observation, no less beautiful
and striking, that in order to induce the closure of the
Dionaa leaf the application of two successive stimuli
within proper intervals is necessary. He deduces two
leading principles — (i) that plants, like animals, being
in a condition of protoplasmic continuity, are, by virtue
of it, possessed of a power of general contractility ; and
(2) that the positions taken up by the Oxalis and other
leaves under the action of the tropical sun are due to heat
and not light effects. The other lecture, by Prof. W. P.
Wilson, on " The Influence of External Conditions on
Plant Life," contains little new, and is in part vague
and unintelligible.

The volume closes with an illustrated report on " The
Marine Biological Stations of Europe," by Dr. Bashford
Dean, and an appendix on " The Work and the Aims of
the Marine Biological Laboratory " at Wood's Holl, by
Prof. Whitman, giving a list of close upon too papers
produced under its auspices.

It cannot have escaped the reader's notice th.';t the con-
tents of the book are largely reports upon experimental
work which bears directly upon the recent theories of
Weismann, so popular in our own land. Contemporane-
ously with the labours of Wilson and Loeb, of which an
account is given in its pages, the work of Driesch,
Herbst, and others, which carries us back through that of
Vejdovsky, Chun, and Chabr>', to the classical obser-
vation of Ha:ckcl, now twenty-five years old, that
detached portions of the fully segmented ovum (of the
Siphonophoran Crystallodcs) may give rise to young
animals, have materially modified our conception of
certain fundamentals of embryology. The observation
that variation in development, '' twinning," and other kin-
dred phenomena, may bear a definite relationship to
variation in temperature, chemical composition, and
osmotic pressure of the surrounding medium, is now
well established. The discovery that after the removal
of cither the micromcrcs or macromeres, the segmenting
embryonic mass may still form a gastrula — that the
differentiation of outer layer cells to form certain larval
organs may be directly a question of location — and that
certain blastomcres if separated at the two-celled stage
may each give rise to an embryo one-half size, and if
isolated at the four-celled stage to one of one-fourth
size, is very extraordinary ; and, viewing the situa-
tion generally, one is prone to ask where now are
the said theories i" Concerning them. Prof. Wilson
replies " the fine spun thread . . . leads us little
by little into an unknown region, so remote from the
lerra firina of observed fact that verification and
disproof are alike impossible." The theories of Weis-
mann were ori>;inally framed with the laudable desire of
stimulating inquiry. They do not seek to explain the

NO. 1308, VOL. 51]

actual modus operandi of the hereditary process so much
as to localise the seat of hereditary tendency and influ-
ence. The implication that neither proof nor disproof are
possible, applies, for the matter of that, to even the
theory of descent with modification 7'cr.f;/.f that of special
creation. The educated mind has, however, upon purely
logical grounds, chosen between the alternatives in this
instance, and it may be safely relied upon to do so in
the other. G. B. H.

NOTES.

The anniversary meeting of the Royal Society will be held
on Friday, November 30.

At the first monthly meeting of the Royal Statistical Society
for the present session, held on Tuesday afternoon, a gold Guy
Medal was presented lo Dr. Robert Gifl'en, C.B., F.R.S., in
recognition of his long and exceptional services to statistical
science.

M. Louis Figuier, who died on November S, was an
eminent populariser of the results of scientific research. He
was born at Montpellier in 1819, where he took his degree
of Doctor of Medicine in 1841. A few years later he
became Professor of Pharmacy in the Paris Ecole de Pharmacie.
In 1850 he took his degree as Doctor of Science at Toulouse,
lie published some important memoirs on chemical subjects,
but will be remembered chiefly for his numerous works on
popular science. Since 1856, he issued every year the Aniu'e
Scieiilifique, in which he summarised the most interesting and
important scientific discoveries of the year.

The Manchester correspondent of the Lancet says that the
sum of ;£'783 \os. 31/. has been raised for the fund in memory of
the late Prof. Milnes Marshall, and after expenses £^(iO 2s. ^J.
will be left. Of this sum ;{;^65o have been invested in Man-
chester Corporation Stock to provide for the maintenance of
the Marshall Biological Library given to the Owens College by
the relatives of Prof. Marshall, while ;f 102 8i. 6./. have been
similarly invested to provide a " Marshall Gold Medal" to be
annually competed for at the Owens College athletic sports.

Dr. J. ScHKlNER, of the Potsdam Astro-Physical Observa-
tory, has been appointed Extraordinary Professor in Berlin
University.

A severe earth<iuake occurred on Friday last in Sicily and
Southern Italy. The shocks were felt not only in the city and
district of Messina, and several other places in Sicily, but also
throughout the province of Reggio di Calabria, in Southern
Italy. The disturbance was also recorded upon the seismic in-
struments at Rome and Ischia. Shocks of more or less violence
were felt at Palmi, Seminara, Santa Eufemia, and San Pro-
copio, in the province of Reggio di Calabria. The centre of
the disturbance in thi< province appears to have been in the
west, round the towns of Palmi and ISagnara. San Procopio,
a town near Palmi, h.-is been almost entirely destroyed, and it is
estimated that at least two hundred persons have perished at
that place alone. Since Friday the district of Kcggio di
Calabria has been slightly disturbed, but these tremors have
not caused any further damage.

The Drapers' Company have contributed /'20 lo the funds of
the Epjjing Forest Museum, now being formed in (^uecn
Elizabeth's Lodge, Chingford, by the Essex Field Club, under
the sanction of ihc Epping Forest Committee of the Corporation
of London. The museum is intended to illustrate the natural
history, antiquities, and scenery of this beautiful district.

The Weekly Weather Refcrl o{ the lyih instant shows that
in many districts the rainfall greatly exceeded the mean ; over
all the southern counties of Engl.and the amount was nearly four
times as much as the average. The largest amounts recorded at

November 22. 1894I

NATURE

individual stations during the week were 6-25 inches at God-
manstone (near Dorchester), 5-51 inches at Scilly, 5-13 inches
at Killarney, and 470 inches at Falmouth, while 460 inches
fell at Crowborough, Sussex, in six days. The rainfall since the
beginning of the year has now exceeded the average in all dis-
tricts, except the Midland Counties and the west coast of Scot-
land. The excess in the south of England and south of Ireland
amounts to over five inches.

Reports in the medical papers show that the enthusiasm
roused in France by the results of the antitoxin treatment of
diphtheria has by no means abated. We learn from the British
Medical Journal \)i^\. the administrative Society of the Sauve-
teurs de la Seine have presented M. Roux with the Grand
Diph'ime d'llonneur. The Var General Council has voted an
equivalent of £\o for the Pasteur Institute, and ^80 towards
creating a similar institute at Marseilles. The Lille Municipal
Council has declared for the erection of a diphtheria laboratory,
and has opened a subscription in order to collect the necessary
funds. The city of Lille has subscribed /■looo. The Council
has undertaken to furnish from /i400to ^1600 for a municipal
bacteriological laboratory. The Havre municipality has voted
^200 towards the cost of establishing a laboratory for the pre-
paration of anti-diphtheric serum. The Paris correspondent of
the Lancet reports that the Municipal Council of Paris has voted
a subvention of fifteen thousand francs to the Pasteur Institute
in aid of the preparation and, distribution of anti-toxin. A
sum of seven thousand six hundred francs has also been voted
for the erection of accommodation for immune horses, and an
allowance of fifteen hundred francs has been made to enable
the institute to prepare and distribute anti-diphtheric serum
during the present month and the month of December. In our
own country. Sir Joseph Lister's appeal for funds has resulted
in the sum of ^£'850 being raised. It is estimated that at least
;^200O will be required by the British Institute of Preventive
Medicine in order to establish an installation for the manufac-
ture of a sufficient quantity of the fluid to supply the demand.

A MARINIC laboratory founded and maintained by a religious
corporation, is probably unique of its kind ; but such is the case
with the Russian station on the island of Solowetzk, in the
White Sea, as an interesting article in Die Natur informs us.
From the early part of the fifteenth century Solowelzk or Holy
Island has been the seat of an important monastery, but the
foundation, in 1S81, of a marine laboratory in connection with
it was principally due to the efforts of Prof. R. Wagner, of St.
Petersburg, and to the friendly offices of the late Archimandrite
Mileti. The laboratory results from the conversion of a herring
factory already existing there on a favourable site. It is now a
convenient two-storied building, furnished with tank-room,
museum, and six work-rooms with large windows, fully provided
with all necessary utensils and reagents. Perpetual day is
enjoyed from the middle of May to the middle of July, and
during that period the energetic naturalist can work continuously
with his microscope night and day, if he so pleases. A little
fleet of sailing-boats is at the disposal of the station, but, owing
to the uncertainty of the winds, a steam-launch ii found to be a
great desideratum. The attendants are selected from the
peasants serving longer or shorter periods in the monastery, and
the laboratory naturally suffers a good deal of inconvenience
from the frequent changes which ensue. The director for some
three years past has been M. Knipowitsch, whose local know-
ledge has considerably facilitated the researches of visiting
naturalists. A long deep lagoon on the east of the island
presents features of unusual interest to the biologist. Owing to
its physical conformation the lower layers of water remain
throughout the year at a constant low temperature, enabling
such .'\rctic forms as Yoldia arctica to survive through the

NO. I30S, VOL. 5 l]

summer heat ; while the warming of the tidal surface waters in
summer favours the development of such forms as Cyprina
islandica, and markedly hastens the development of medusae
such as Cyanea and Aurelia. Solowetzk may be reached from
St. Petersburg either via Jaroslaw and Archangel, or, more
directly, viA the lakes, Povjonelz and Szumski.

Captain Wiggins, who had left the Yenesei in the Slj\:rne>:,
late in the season for England, has been wrecked in Yugor
Strait, but a telegram from .\rchangel states that all on board
are well. Particulars have not yet been received, but the fact
points to a serious condition of the ice in the Kara Sea.

The Christm.as Lectures to Young People, arranged by the
Royal Geographical Society, will this year be delivered by Dr.
H. R. Mill. The course, entitled " Holiday Geography," will
include four lectures, dealing respectively with maps as holiday
companions ; geographical pictures, with special reference to
amateur photography ; a neglected corner — the English lakes ;
and a geographical holiday on the edge of the Alps. The
lectures will take place in the map-room of the Royal
Geographical Society, and will be profusely illustrated by the
lantern.

The Royal Geographical Society initiated the new technical
meetings for geographers on Monday afternoon, by the discus-
sion of a piper on a pre-Columbian discovery of America, by
Mr. Yule Oldham. The claim for the discovery of Brazil by a
Portuguese navigator in 1447 was based on a map of Andrea
Biancho prepared in 144S, on which an "authentic island 1500
miles west of Cape Verde" was shown. This evidence was
supported by various additional arguments, including the St.
Brandan's Island of Martin Behaim's globe of 1492. A
very lively discussion ensued, in which Mr. E. G. Ravenstein,
Mr. Payne, Mr. Beazeley, Dr. Schlichter, Mr. Delmar Morgan,
and others took part. The general conclusion of the meeting
was unfavourable to the view of the early discovery of Brazil,
but all speakers united in expressing their admiration of the
manner in which Mr. Oldham marshalled the facts and ex-
pounded his theory.

Dr. .\dolf E. Forster, of Vienna, has made a very careful
study of the temperature variations in the rivers of Central
Europe, which has just been published in Prof. Penck's
Geographisclie Al'liaitdluiigen. He has collected a great number
of isolated sets of observations, in several cases extending over
many years, which have been made by different observers on the
main rivers and tributaries of the Vistula, Oder, Elbe, Weser,
Rhine, Danube, Adige, Po, Rhone, Loire, Seine, and Thames.
These are discussed in order to bring out the amount of diurnal
range, the effect on the mean result of different methods of
observations (including the effect of depth), the relation between
the temperature of water and air in different classes of rivers,
the annual march of river-temperature, the variability of water-
temperature from the long-period means, the influence of ice,
and various other factors, such as the effect of dynamical heat-
ing on account of fall from higher to lower levels. Dr. Forster
recognises the necessity of farther observations of a strictly
comparable kind in order to obtain sure results, especially with
regard to the bearing of river-temperature on meteorology ; but
the results he has obtained are of great interest. He shows
how the relation of air- and water-temperature depends on the
character of the water-surface considered. In glacier-fed rivers
the air is colder than the water only for four months in winter and
early spring ; in summer the maximum temperature of air and
water coincides with the greatest excess of aii-temperature. .\
similar though less marked relation holds good for mountain
streams which are not fed by glaciers. In lakes and the outlets
of lakes the air-temperature is higher than that of the water
only during the four months during which heat is being stored,
th curves crossing close to the maximum. In rivers flowiog

^4

NATURE

[November 22, 1894

over plains, such as the Oder at Breslan, and the Marne at its
junction with the Seine, the water-temperature remains through-
out the year from one to three degrees Centigrade warmer than
t 1 ■

Herr E. Lecher, in the Wiener Bcrichle, gives an account
of an experiment he has performed to test whether when a
magnet turns about its magnetic axis the lines of force remain
at rest or turn with the magnet. A magnet is dividei by an
equatorialiplane into two parts, which can turn independently.
I'nder these circumstances it is possible, by means of suitable
contact brushes, to obtain from the two extremities of the
magnet an induced current of such a magnitude as cannot
be explained by the cutting of the rotating lines of force by the
extremely short brushes employed. These currents can be ex-
plained if we suppose, as did Faraday at one time, that a
rotating magnet cuts its own lines of force which remain fixed
in space.

Mr. Carl B.\Rfs, in the current number of the American
journal <ij Science, describes a simple chronograph pendulum
which is likely to be very useful to those who have no break-
citcuit chronometer or seconds clock at their disposal. It is a
simple mechanism by which an ordinary seconds pendulum is
both kept in motion and made to record its oscillations on one
or more chronographs sharply. The heavy metallic bob of the
pendulum is electrically connected with the knife-edge, and its
top is surmounted by a soft iron armature, which is attracted
during part of the swing by an electromagnet, and thus kept
in motion. A longer and very much lighter pendulum, con-
sisting of a flat bobsu-pendeJ by two wires, is suspended by the
side of the first, and swings in the same plane, but with a
longer period. As the heavy pendulum approaches it, it
(ouches a platinum spring projecting from the other bob. makes
current for a moment, and works the chronograph, and at the
same lime sends the current through the electromagnet. The
contact is quite momentary, as the spring causes the wire
pendulum to be hurled off ballistically. On its return it is
brought to rest, without rebounding, by a stop, against which it
leans till the seconds pendulum returns. The bob of the light
peoduluoi is made up of two small square parallel plates,
between which the wires and the platinum strip are clutched by
a single central screw. A band of platinum foil is wrapped
round the heavy bob, in order to ensure reliable electric contact.
The chronographs and the electromagnet are connected in
parallel. The records show that the time of contact does not
reach o'l sec. It is desirable to use electromagnets of high
resistance to prevent exhausting the battery.

Part 1. of vol. vii. of Cohn's Beilmge is taken up with a
long paper, by Dr. W. Rothert, on Heliotropism. He finds
that the heliotropic .stimulus received on one part may be trans-
mitted to another part of the same organ, or even to a diHerent
organ, and there give rise to heliotropic curvature. The trans-
mission can only take place in a basipetal direction, and its rate
i< always small : in favourable cases 2 cm. per hour. Contrary
(o Darwin's views, he believes that the whole region which
b capable of heliotropic curvature, is also heliotropically sensi-
tive, although this sensitiveness is often unequally dislributed
in the same region. In all cases of this unequal distribution,
it is a small region at the ap<x of the organ which is
distinguished by a greater sensitivenes', whilst the rest ex-
hibits this sensitiveness often in a far less degree. Further,
the author investigated the effects of cutting off the apex of the
cotyledon of seedlings of grasses, and found that this gives rise
to two independent phenomena : a diminution in the rate of
growth of the base, and a complete suspension of its heliotropic
and gcotropic sensitiveness. Both these effecls are, however,
only temporary. It was also unexpectedly found that these
effects aic not consequent on every injury done to the cotyledon,

NO. 1308, VOL. 51]

but that large cuts made either into the apex, or even two semi-
sections made below the apex from opposite sides of the org.nn,
and only 2 mm. apart, do not cause the diminution in the r-ite
of growth, nor the sTispension of heliotropic and geotropic
sensitiveness, but that this is only effected by the complete
section of the cotyledon.

Messrs. \V. Wesley and Son's "Natural History and
Scientific Book Circular," No. 122, contains a full classified list
of important works on botany.

The thirteenth monthly part of "The Royal Natural
History " ^ Frederick Warne and Co.), bein^ the first part of
the third volume of the work, has been published.

The Royal College of Physicians, Edinburgh, has just issued
the fifth volume of Reports from their Laboratory, edited by
Drs. J. Batty Tuke and D. Noel Patou. The volume presents
the results of investigations carried out during the past two
years.

The ninth number of the handy and useful Alembic Club
Refrinls (Edinburgh : W. F. Clay) is devoted to Davy's
papers on the property and nature of " muriatic acid " and
" oxymuriatic acid," published in the Philosophical Transac-
tion: between iSog and iSlS. Our readers need hardly he
reminded that though Gay-Lussac and Thenard were inclined
to believe in the elementary nature of the latter, it was Davy
who established the correctness of this view. This reprint of
the eight communications to the Royal Society, on his experi-
ments to demonstrate the elementary nature of chlorine, will be
valued by students of historical chemistry.

We have received No. 6 of The Scientific Roll, conducted
by .\. Ramsay, and dealing with the baric condition of the
atmosphere. This publication is intended to be a summary of
what is known of this subject from the works of various writers,
so that anyone may make himself acquainted with what has
been written without obtaining and reading the original books,
some of which are now difficult of access. The present number
contains notes taken from Prof. Kimtz' Vorlesiingen uher
Meteorolc:;ie, published in 1S40, and translated into English by
Mr. C. V. Walker in 1S45. I:i addition to retaining the
original scales, the author reduces ail values to what he terms
the " baric unit," which is taken as equivalent to one million
pounds weight on the square mile. Thus one inch of mercury
at 60° F., and under the ordinary pressure of sea-level, corre-
sponds to 2000 such baric units, and a millimetre under the
same conditions to 7874 baric units.

Prof. Lothar Meyer communicates to the Berichlc a
warning note concerning the dangerous nature of explosive mix-
tures of acetylene and oxygen. It is a well-known fact, fre-
quently demonstrated upon chemical lecture-tables, that
detonating mixtures of hydrogen and oxygen, or of marsh gas,
ethylene, or carbon monoxide and oxygen, may be ignited in an
open glass cylinder without danger provided the vessel is not
narrowed at the neck, which would be likely to cause undue
pressure. Prof. Meyer states that he has frequently performed
the experiment with the above gaseous mixtures, employing a
strong straight glass cylinder four centimetres wide and with
very thick base, without ever having experieiice<l an accident.
Upon performing the experiment recently, however, with a
mixture of acetylene and two and a half to three times its volume
of oxygen, igniting the gas by approaching the mouth of the
cylinder to a flame, the cylinder was blown to innumerable frag-
ments in his hand, happily and almost miraculously without
injuring him, although unprotected by a cloth, and the report
of the explosion «as so loud as to deafen for a time those in the
neighbourhood. It has long been known that acetylene ex-
plodes with oxygen in closed vessels with great violence, fre-
quently destroying an eudiometer, but this remarkable destruc-

t

November 22, 1894]

NA rURE

8=;

tion of an open cylinder is a new evidence of its disruptive
force. In the year 18S4 Prof. Meyer, in conjunction with Prof.
Seubert, showed that the detonating mixture of acetylene and
oxygen ignites at a lower pressure than all other combustible
gases, a pressure equal to thirty-two millimetres of mercury
being sufficient to enable it to explode, while hydrogen and
oxygen require a pressure of at least one hundred millimetres,
and carbon monoxide and oxygen over two hundred millimetres.
This, however, is not sufficient to account for the enormous
pressure developed in an open cylinder. A^oreover, it cannot
be due to the more rr^pid rate of propagation of the explosion,
for M. Berthelot and Prof. Dixon' have independently found
that the rapidity in the case of the acetylene detonating mixture
is but slightly greater than in the mixtures of oxygen with ethylene
or marsh gas, and much less than in the case of a mixture of
hydrogen and oxygen. Prof. Meyer suggests that the smaller
amount of hydrogen contained in acetylene than the other hydro-
carbons, resulting in the production of less water vapour and
relatively more carbon dioxide, together with the fact that the
theoretical temperature of the combustion calculated from exist-
ing thermal data, is extremely high in the case of acetylene, may
afford some explanation of the extraordinary energy developed
during the explosion of the latter.

A PURE white di-sulphide of tin has been obtained by Dr.
Schmidt in the laboratory of the Berlin University, which is
further distinguished by the property of being readily soluble in
ammonium carbonate. It may easily be pre.>ared as follows :
Metallic tin is first dissolved in hydrochloric acid, and the
stannous chloride oxidised by digestion with nitric acid to
stannic chloride, and the excess of acid largely removed by
evaporation. After dilution with water ths tin is precipitated
as the ordinary yellow sulphide by sulphuretted hydrogen. The
washed precipitate is next freed from traces of arsenic by solu-
tion in concentrated hydrochloric acid and reprecipitating
the diluted and filtered solution with sulphuretted hydrogen.
The well-washed yellow precipitate is then digested with a
large excess of ammonium hydrate for some days at the
ordinary temperature, when the whole of it eventually dissolves
except small traces of the black sulphides of lead and bismuth.
Upon diluting the clear ammoniacal solution and neutralising it
with dilute sulphuric acid, an almost perfectly while precioitale
is obtained. This precipitate dissolves at once almost com-
pletely in ammonium carbonate, and upon again neutralising
with dilute sulphuric acid the disulphide precipitated is pure
white. This new form of stannic sulphide is very voluminous,
and it apparently owes its absence of colour and greater bulk
to the fact that stannic sulphide here exists either in a difterent
state of molecular aggregation or of hydration. It is signifi-
cant that upon drying it becomes amber-yellow and loses its
property of dissolving in ammonium carbonate.

The additions to the Zoological Society's Gardens during the
past week include a Lesser White-nosed Monkey {Ccrcopithecns
pttaurista), a Pel's Owl (Scolopcliti pelt), an Angolan Vulture
{Gypohitrax angolensis), a Black Kite {A/i/vm migrans}, a
Buzzard (Buleo, sp. inc. ) from West Africa, presented by Mr.

C. B. Mitford ; two Baboons {Cynoctphaliis, sp. inc.) from

East Africa, presented by Mr. Charles Palmer ; a Chilian Sea
Eagle (Geratioitliis mslanoleuius) from South America, pre-
j sented by the Rev. Fred L. Curne ; two Bronze-winged
I Pigeons {/Viaps chalcoptcra) from .\ustralia, presented by Mrs.
Amy Jones ; ten Surinam Toads (/'/pra amcricaiia) from
Surinam, presented by Mr. F. E. Blaauw ; five Three-streaked
Euprepes (Eiiprefres triviltalus) from South Africa, presented
by Mr. J. E. Matcham : a Muscat Gazelle {GazeHa mtiscalensis)
from Muscat, an Echnida {Eckiiida /lyilrix) from New South
Wales, deposited; four Lapwings {Vantllin crislalus), British,
purchased.

WO. f3o8, VOL. 51]

OUR ASTRONOMICAL COLUMN.

Observations 01 the Transit of Mercury.— Several
French astronomers made preparations for observing the recent
transit of Mercury across the sun, but the weather conditions on
the other side of the Channel were just as unfavourable as they
were here. The current Complss renclus contains a brief note on
the transit, by M. Trouvelot. This observer saw Mercury pro-
jected upon the sun at 4h, 12m. The planet was sharply defined,
and appeared as a circular, imensely black, spot on the luminous
background of the sun. In spile of careful observation, M.
Trouvelot was unable to detect any trace of a luminous ring
such as he observed round the planet during the transit 01
187S. The unfavourable conditions of observation, however,
are sufficient to explain the absence of the phenomenon.

Dr. Janssen also contributes a note on the transit of Mercur)'
to Comptes retuliis. He intended to look particularly for the
"black-drop" observed during the transit of Venus in 1874, but
clouds prevented the observation.

Ephe.meris ok E.ncke's Comet.— The following positions
for Encke's Comet duiing this year are from an ephemeris given
by Dr. O. Backlund in the Astronomiiche Naclirichlen, No.
3263. The comet will pass perihelion on February 4, 1895.
In the year 1S62, its perihelion passage occurred on February 6.

Ephemirii for oh. Bcrliit Mian Time,
i8y4. R..^ app. Decl. app.

h. ni. s. . , /,

Nov. 22 ... 223554-79 ... -f 9" 651-0

24 ■•■ 33 2502 • • 8 40 53-6

„ 26 ... 31 793 8 15 59-1

>. 28 ... 29 3-11 7 52 9-1

3° ■•■ 27 9-98 ... 7 29 240

Dec. 2 ... 25 28-18 ... 7 7 43-2

4 ■•■ 23 57-09 ... 6 47 5-3

,, 6 ... 22 3602 ... 6 27 27-9

8 ... 21 24-29 ... 6 8 485

,, 10 ... 20 21-19 ••- 5 51 36

„ 12 ... 19 25-94 ... 5 34 8-3

„ 14 ... 18 37-75 ... 5 17 577

„ l6 ... 17 5577 ... 5 2 257

„ 18 ... 17 19-11 ... 4 47 25-7

,, 20 ... 16 4682 ... 4 32 506

,, 22 ... 16 17-82 ... 4 iS 320

,, 24 ... 15 50-85 ... 4 4 190

,, 26 ... 15 24-59 ... 3 49 592

„ 28 ... 14 57-30 ... 3 35 182

„ 30 ... 22 14 2709 ... -^ 3 19 583

Recent Observations of Jupiter.- Prof. E. E. Barnard
communicates to this month's Astronomy and Astro-Physics an
account of his recent observations of the great red spot and other
markings on Jupiter. The following points with regard to these
features are of interest to observers : " The surface of Jupiter
is very strongly marked, during this opposition, by two" broad
reddish belts, one on each side of the equator, and a bi-oad white
belt between them at the equator. The great red spot is fairly
distinct in outline, though quite pale — a feeble red. The great
bay in the south equatorial belt north of the red spot is still per-
sistent and well marked." Prof. Barnard has observed a
number of small black and white spots in Jupiter's northern
hemisphere. Two of these objects, a black and a white spot,
can easily be seen opposite the great red spot on the planet's
disc. Prof. Barnard's measures indicate that the white spot
will be in conjunction with the dark one about the middle of
January next year, but as the two objects are not exactly on the
same parallel, they will only graze in passing one another. The
black spot appears to have about the same rotation period of the
great red spot. Numerous white spots have been observed in
Jupiter's southern hemisphere. .\ few dusky markings have
also been seen on the great white equatorial belt.

THE NEW CYPRESS OF NYASALAND.
TN the most easterly corner of the British Protectorate ofNyasa-
land, immediately south of Lake Shirwa (between 35' and
36" E. lal, and a little north of 16° S. lat.), lies the large isolated
mountain-mass of Milanji. From the plains which surround it
the land rises gradually to a height of about 3000 feet, and
for^js the lower spurs of the mountain. Above these outlic
the mount.iin is carried up another 3000 feet in abrupt elevatior* /
only broken in places where the larger streams flow down. ""'^

86

NA TURE

[November 22, 1894

iimpart of cliffs borders the upper plateau of Milanji, which is
elevated about 6000 feet above the sea-level, and is ol consider-
able extent, thouRh split up into various portions by ravines and
precipices. In the centre of the plaleau peaks rise to a further
height of 3500 feet, thus giving Milanji a total elevation of
nearly 10,000 feet above the sea-level.'

Mr. Alexander Whyte, the naturalist attached to the
staff of Mr. H. H. Johnston, C.B., M.B.M. Commissioner
and Consul-General, who usually resides at Zomba, made a
botanical excursion to Milanji in 1S92, and obtained a good
series of the mountain-plants. An account of this collection,
prepared by the officers of the Botanical Department in the
British Museum, is given in a recently issued part of the Botanical
Transactions of the Lionean Society.

photograph, and kindly lent to us by the Linnean Society. The
timber is of a pale reddish colour, of excellent quality, and easily
worked. The bark on the old trees is of great thickness, consist-
ing of layers which are .innually shed .ind renewed. The foliage
recalls that of the juniper, while the fruits or cones, which are
crowded from four to six together on short lateral shoots, are
about three-quarters of an inch long, and from that to one inch
wide when open. They consist of four thick woody scales,
united below, spreading above, and bearing at their bases on
the internal surface a number of small winged seeds.

Examination of the specimens sent home has shown that we
are here dealing with a new species of WidJringtonia, a small
genus of conifers allied to the cypress and juniper. Mr. Whyte's
discovery has considerable scientific interest, from the fact that

The Milanji Qyfmi(Wi(Uiringt0Hia wliyUi).

'■'^>

Among the many plants new to science discovered by Mr.
Whytc, and descrilwd in this memoir, one is of special interest,
owing to its importance from an economic point of view.
' In his exploration of the mountain, Mr. Whytewas much im-
prei«ed with "a large cypress," which formed the most striking
feature of the upper plateau. One prosirate trunk, and thai by
no means the largest seen, measured 140 feet in length, with a
[liameter of sJ feet at six feet from the l).vse, and had a clean,
^raight stem of ninety feet. In other coses long straggling
nchcs are given off nearer the base, as shown in the accom-
'ing ligure, pre|)ared by Mr. Worlliinglon Smith from a

• KoulM and Dislricia in Soulhtm Nyasaland," by llcnrain L.
, RE, liiocrapli. Jtiurn., November iSjj.

.0. I30S. VOL. 51]

it extends the geographical r.mge of the genus, hitherto known
only from South Africa, Madagascar and Mauritius, itito
tropical .Mrica ; and his name has been fittingly associated with
the plant, which will henceforth be known .as WulJiinglonia
:i'hyUi,

Its nearest ally, W. jiiiii/'eroidts, is found in the Ccderberg
Mountains, Cape Colony, where, according lo a note by
I'arlalore in Dc Caiidollc s PioJromuS (vol. xvi. part 2, p. 442),
it once formed large forests, but is now rare. 'I'hc Milanji
species is also threatened with extinction ; in this case by the
buih-fires, the devastating effects of which, .Mr. Whytc says, it
is deplorable to witness, and which reach even the lofty and
almost inaccessible plateau. These fires, originating during the

November 22, 1894]

NATURE

87

dry months of August and September in the villages on the
lower slopes of the mountain, gradually creep up the precipitous
cliffs from tuft lo tuft of dried herbage till they gain the grassy
table-lands, and raging over the plain eat their way along the
edges of the remaining belts of forest ; annually scorching, if not
burning, the bark and timber of the outside trees, and killing
outright the young seedlings. In exceptionally dry seasons
even the damper gorges are invaded, and Mr. Whyte describes
hundreds of giant trees lying prostrate and piled on each other
in all stages of destruction. We are glad to learn that Mr.
Johnston, under whose directions Mr. Whyte's exploration was
made, has taken steps to prevent a recurrence of such disasters.

M'idiiriitgtonia zohytei promises to be of great economic value
from the excellent quality of its timber for building purposes
and furniture. It is easily worked, and is moreover a tree of
rapid growth, for Mr. Whyte tells us that in a plantation which
he has formed near the residency at Zomba, three-year-old
seedlings have already reached a height of ten feet.

Seeds of the nev/ conifer, forwarded by Mr. Whyte, reached
this country in 1S93, and healthy seedlings have been raised
in the Royal Gardens, Kew ; in the Botanical Gardens, Edin-
burgh ; in Messrs, Veitch's Nurseries ; and in the Zoological
Society's Gardens ; so that we may hope to see this fine tree
ultimately established in Europe.

The existence of a large cedar-like tree on Milanji was first
discovered by the Rev. Robert Acland, of the Blanlyre Mission,
who visited the mountain in 1889 for the purpose of fou'-ding a
Mission Station. In Mr. Buchanan's narrative of his journey
along the southern frontier of Nyasaland (Proc. R. Geogr. Soc.
1891, p. 271) it will be found alluded to as "a species of pine-
tree " existing in the ravines on the north-eastern slope. In the
latter part of 1891, Dr. W. A. Scott and Mr. Henry Brown
made the first ascent of Milanji, going up the southern face, and
ascertained the existence of large forests of the so-called
" pine" at an altitude of 6000 feet above sea-level. A month
later Mr. Whyte succeeded in ascending to the trees, and, as
already stated, obtained the first specimens which reached this
country, and enabled the tree to be classified and described.

When Fort Lister was founded in 1893, the cedar forests were
found to come down to a much lower altitude on the north-east
slopes of Mt. Milanji, and .idvantage was at once taken
of this to procure a supply of the timber. It was cut up on the
spot, and the planks carried to Zomba, where they have been
employed for many purposes. When the residency at Zomba was
re-roofed with iron this timber was used for the woodwork.
There can be, therefore, no question about the value of this
discovery.

SCHIAPARELLI ON MARS.

'T'HE following extracts from a translation communicated to

■*■ Astronomy and Aitro-Phyiics, by Prof. W. H. Pickering,

I "^ of special interest at the present time, for they set forth

' . hiaparelli's observations of the planet Mars, and show his

■ "'ews on various Martian phenomena. The original article was

contributed by this keen observer to Nalitra cd Arte.

The Polar Caps.
j Many of the first astronomers who studied Mars with the
I telescope, noted on the outline of its disc two brilliant white
spots of rounded form and of variable size. In process of time
it was observed that whilst the ordinary spots upon Mars were dis-
placed rapidly in const ijuence of the planet's daily rotation, chang-
ing in a few hours both their position and their perspective, that
the two white spots remained sensibly motionless at their posts.
It was concluded rightly from this, that they must occupy the
poles of rotation of ihe planet, or at least must be found very
near to them. Consequently they were given the name of
polar caps or spots. And not without reason is it conjectured,
that these represent upon Mars an immense mass of snow and ice,
iinilar to that which today prevents navigators from reaching the
I' lies of the Earth. We are led to this conclusion not only
l>y the analogy of aspect and of place, but also by another im-
j'"rtant observation.

As things stand, it is manifest, that if the while polar spots of
M.xrs represent snow and ice, they should continue to decrease
111 size with the appro.ich of summer in those places, and in-
crease during the winter. Now this very fact is observed in the
most evident manner. In the second half of the year 1892 the
southern polar cap was in full view ; during that interval, and
especially in the months of July and August, its rapid diminu-

NO. 1308, VOL. 5 l]

tion from week to wee'K was very evident, even to those
observing with -common telescopes. This snow (for we may
well call it so), which in the beginning reached as far as
latitude -}o\ and formed a cap of over 2000 kilometres (1200
miles) in diameter, progressively diminished, so that two or
three months later little more of it remained than an area of
perhaps 300 kilometres (180 miles), at the most, and still less
was seen later in the last days of 1892.' In these months the
southern hemisphere of Mars had its summer ; the summer
solstice occurring upon October 13. Correspondingly the mass
of snow surrounding the northern pole should have increased ;
but this fact was not observable, since that pole was situated in
Ihe hemisphere of Mars which was opposite to that facing the
Earth. The melting of the northern snow was seen in its turn
in the years 1SS2, 1884, and 1886,

The southern snow, however, presents this peculiarity, that
the centre of its irregularly rounded figure does not coincide
exactly with the pole, but is situated at another point, which is
nearly always the same, and is distant from the pole about 300
kilometres (180 miles) in the direction of the Mare Erythrxum.
From this we conclude that when the area of the snow is
reduced to its smallest extent, that the south pole of Mars is
uncovered ; and therefore, perhaps, the problem of reaching it
upon this planet is easier than upon the Earth. The southern
snow is in the midst of a huge dark spot, which with its
branches occupies nearly one-third of the whole surface of
Mars, and is supposed to represent its principal ocean. Hence
the analogy with our arctic and antarctic snows may be said to
be complete, and especially so with the antarctic one.

The mass of the northern snow-cap of Mars is on the other
hand centred almost exactly upon its pole. It is located in a
region of yellow colour, which we are accustomed to consider
as representing the continent of the planet. From this arises a
singular phenomenon which has no analogy upon the Earth.
At the melting of the snows, accumulated at that pole during
the long night of ten months and more, the liquid mass produced
in that operation is diffused around the circumference of the
snowy region, converting a large zone of surrounding land into
a temporary sea, and filling all the lower regions. This pro-
duces a gigantic inundation, which has led some observers to
suppose the existence of another ocean in those parts, but which
does not really exist in that place, at least as a permanent sea.
We see then (the last opportunity was in 18S4) the white spot
of the snow surrounded by a dark zone, which follows its peri-
meter in its progressive diminution, upon a constantly diminish-
ing circumference. The outer part of this zone branches
out into dark lines, which occupy all the surrounding region,
and seem to be distributory canals, by which the liquid mass
may return to its natural position. This produces in these
regions very extensive lakes, such as that designated upon the
map by the name of Lacus Hyferhorcus ; the neighbouring
interior sea called Mare Acidalium becomes more black, and
more conspicuous. And it is to be remembered as a very pro-
bable thing, that the flowing of this melted snow is the cause
which determines principally the hydrographic state of the
planet, and the variations that are periodically observed in its
aspect. Something similar would be seen upon the Earth, if
one of our poles came to be located suddenly in the centre of
.\sia or of Africa. As things stand at present, we may find a
miniature image of these conditions in the flooding that is
observed in our streams at the melting of the Alpine snows.

Other white spots of a transitory character, and of a less
regular arrangement, are formed in the southern hemisphere,
upon the islands near the pole, and also in the opposite hemi-
sphere, whitish regions appear at times surrounding the north
pole, and reaching to 50" and 55^ of latitude. They are per-
haps transitory snows, similar to those which are observed in
our latitudes. But also in the torrid zone of Mars are seen
some very small white spots more or le>s persistent. Perhaps
we may be permitted to account for these by the existence of
a mountain capalile of supporting extensive ice-fields. The
existence of such a mountain has been supposed also by some
recent observers, founded upon other facts.

Martian Mf.teoroi.ogv.
As has been slated, the polar snows of Mars prove, in an in-
controvertible manner, that this planet, like the Earth, is sur-
rounded by an atmosphere capable of transporting vapour from
one place to another. These snows are in fact precipitations of

1 A note on the melting of the southern snow-cap this year appeared
the last number of Natuke (p. 64).

88

NATURE

[November 22, 1894

vapour, condensed by the cold, and carried with it successively.
How catrietl with it, if not by atmospheric movement ? The
existence of an atmosphere charged with vapour has been con-
firmed also by spectroscopic observations, principally those of
Vogel ; according to which this atmosphere must be of a com-
position differing little from our own, and above all viry rich in
aqueous vafour. This is a fact of the highest importance,
because from it we can rightly affirm with much probability,
that to water, and to no other liquid is due the seas of Mars and
its polar snows. When this conclusion is assured beyond all
doubt, another one may be derived from it, of not less import-
ance— that the temperature of the Arean climate, notwith-
standing the greater distance of that planet from the Sun, is of j
•he same order as the temperature of the terrestrial one.
Because, if it were true, as has been supposed by some !
investigators, that the temperature of Mars was on the average j
very low (from 50' to 60' below zero 1 1, it would not be possible
for water vapour to be an important element in the atmosphere
of that planet, nor could water be an important factor in its
physical changes ; but would give place to carbonic acid, or to
some other liquid whose freezing point was much lower.

The elements of the meteorology of Mars seem then to have
a close analogy to those of the Earth. But there are not lack-
ing, as might be expected, causes of dissimilarity. From
circumstances of the smallest moment, nature brings forth an
infinite variety in its operations. Of the greatest influence
must be the different arrangement of the seas and (he continents
upon Mars, and upon the Earth. We have already emphasised
the fact of the extraordinary periodical flood, which at every
revoluliDn of Mars inundates the northern polar region at the
melting of the snow. Let us now add that this inundation is
spread out to a great distance by means of a network of canals,
perhaps constituting the principal mechanism (if not the only
one) by which water and with its organic life) may be diffused
over the arid surface of the planet. Because on Mars it rains
very rarely, or ptrhafs tvcn, it Joi; not rain at a/I.

The atmosphere of Mars is nearly perpetually clear, and
sufficiently transparent to peimit one to recognise, at any
moment whatever, the contours of the seas and continents, and
more than thai, even the minor conl'igurations. Not indeed
that vapours of a certain degree of opacity are lacking, but they
ofTer very little impediment to the study of the topography of
the planet. Here and there we see appear from time to lime a
few whitish spots, changing their position and their form, rarely
extending over a very wide area. They frequent by preference
a few regions, such as the islands of the .l/.jrir Amtrak. and on
the continents, the regions designated on the map with the
names of Klysiutii and Tempe. Their brilliancy generally
diminishes and disappears at the meridian hour of the place,
and is reinforced in the morning and evening, with very marked
variations. It is possible that they may be layers of cloud,
because the upper portions of terrestrial clouds, where they are
illuminated by the Sun, appear white. But various observations
lead us to think that we are dealing rather with a thin veil of fog,
instead of a true nimbus cloud, carrying storms and rain.
iDdecd it may be merely a temporary condensation of vapour,
under the form of dew or hoar-frost.

.Vccotdingly, as fnr as we may he permitted to argue from
the observed faces, the climate of Mars must resemble that of a
clear day upon a high mountain. By day a very strong solar
radiation hanlly mitigated at all by mist or vapour, by night a
cop ous radiation from the soil towards celestial space, and
because of that a very marked refrigeration. Hence a climate
of extremes, and great change; of temperature from day to
night, and from one season to another. And as on the Earth
at altitudes of 50CO and 6ocx) metres (17,000 to 20,000 feet),
the vapour of the atmosphere is condensed only into the solid
form, proilucing those whitish masses of suspended crystals,
which we call cirrus clouds, so in the atmosphere of Mars,
it would be rarely possilile (or would even be impossible) to
find collections of cloud capable of producing rain of any
coniequence. The variation of the temperature from one
season 10 another would be notably increased by their long
I duration, and thus we c.in understand the great freezing and
] melting of the snow, which is renewed in turn at the poles at
\cach complete revolution of the planet around the Sun.

TorocRAriiicAL Tints.

^n its general topography Mars does not present any analogy

I the Earth. A third of its surface is occupied by the great

Auilrale, which is strewn with many islands, and the

continents are cut up by gulfs and ramifications of various
forms. To the general water system belongs an entire series
of small internal seas, of which the Hadriacum and the Tyr-
rhenum communicate with it by wide mouths, whilst the
Cimmerium, the Sirenum, and the Solis Lacus are connected
with it only by means of narrow canals. We shall notice in
the first four a parallel arrangement, which certainly is not
accidental, as also not without reason is the corresponding
position of the peninsulas of Ausonia, Mesperia, and Atlantis.
The colour of the seas of Mars is gener.ally brown, mixed with
grey, but not always of equal intensity in all places, nor is it
the same in the same place at all times. From an absolute
black it may descend to a light grey, or to an ash colour. Such
a diversity of colours may have its origin in various causes, and
is not without analogy also upon the Earth, where it is noted
that the seas of the warm zone are usually much darker th.in
those nearer the pole. The water of the Baltic, for example,
has a light, muddy colour, that is not observed in the -Mediter-
ranean. And thus in the seas of M.irs we see the colour become
darker when the sun approaches their zenith, and summer begins
to rule in that region.

All of the remainder of the planet, as far as the north pole,
is occupied by the mass of the continents, in which, save in a
few areas of relatively small extent, an orange colour pre-
dominates, which sometimes reaches a dark red tint, and in
others descends to yellow and white. The variety in this
colouring is in part of meteorological origin, in part it may
depend on the diverse nature of the soil, but upon its real cause
it is not as yet possible to frame any very well-grounded hypo-
thesis. Some have thought to attribute this colouring to the
atmosphere of Mars, through which the surface of the planet
might be seen coloured, as any terrestrial object becomes red,
when seen through red glass. But many facts are opposed to
this idea, among others, that the polar snows appear always
of the purest white, although the r.iys of light derived from them
traverse twice the atmosphere of Mars under great obliquity. We
must then conclude that the Arean continents appear red and
yellow, because they are so in fact.

Besides these dark and light regions, which we have described
as seas and continents, and of the nature of which there is at
present scarcely left any room for doubt, some others exist,
truly of small extent, of an amphibious nature, which some-
times appear yellowish like the continents, and are sometimes
clothed in brown (even black in certain cases), and assume the
appearance of seas, whilst in other cases their colour is inter-
mediate in lint, and leaves us in doubt to which class of regions
Ihey may belong. Thus, all the islands scattered through the
Mare Australe and the Mare F.rythra;um belong to this category,
so too the long peninsula called Deucalionis Kegio and Tyrrh.-e
Regio, and in the vicinity of the Mare ,\cidalium the regions
designated by the names of Baltia and Nerigos. The most
natural idea, and the one to which we should be led by analogy,
is to suppose these regions to represent huge swamps, in which
the variation in depth of the water produces the diversity of
colours.

Not without reason, then, have we hitherto attributed to the
dark spots of Mars the i)art of seas, and that of continents to
the reddish areas which occupy nearly two-thirds of all the
planet, and we ^hall find later other reasons which confirm
this methoti of reasoning. The continents form in the northern
hemisphere a nearly continuous mass, the only important ex-
ception being the great lake called the Mare Acidalium, of
which the extent may vary according to the time, and which
is connected in some way with the inundations which we have
said were produced by the melting of the snow surrounding the
north pole. To the system of the Marc .\ci<l.-ilium undoubtedly
belong the temporary lake called Lacus llyperboreus and the
Lacus Niliacus. This last is ordinarily separated from the Mare
Acidalium by means of an isthmus or regular dam, of which
the continuity was only seen to be broken once for a
short time in 18S8. Other smaller dark spots are found
here and there in the continental area, which we may designate
as lakes, but they are certainly not permanent lakes like
ours, but are variable in appearance and size according to the
seasons, to the point of wholly disappearing under certain
circumstances. Ismenius L.acus, Lunx Lacus, Trivium Cha-
rontis and I'ropontis are the most conspicuous and durable
ones. There are also smaller ones, such as Lacus Mo ris and
Fons juvenile, which at their maximum size do not exceed 100
to 150 kilometres {Oo to 90 miles) in diameter, and are among
the most difficult objects upon the planet.

.NO. i;o8, VOL. 51]

November 22, 1894J

NA TURE

89

The Canals or Chanmels.

All the vast extent of the continents is' furrowed upon every
side by a network of numerous lines or fine stripes of a more or
less pronounced dark colour, whose aspect is very variable.
These traverse the planet for long distances in regular lines,
that do not at all resemble the winding courses of our streams.
Some of the shorter ones do not reach 500 kilometres (300
miles), others on the other hand extend for many thousands,
occupying a quarter or sometimes even a third of a circum-
ference of the planet. Some of these are very easy to see,
especially that one which is near the extreme left-hand limit of
our map, and is designated by the name of Nilosyrtis. Others
in turn are extremely difficult, and resemble the finest thread of
spider's web drawn across the disc. They are subject also to
great variations in their breadth, which may reach 200 or even
300 kilometres (120 to 180 miles) forthe Nilosyrtis, whilst some
are scarcely 30 kilometres (18 miles) broad.

These lines or stripes are the famous canals of Mars, of
which so much has been said. As far as we have been able to
observe them hitherto, they are certainly fixed configurations
upon the planet. The Nilosyrtis has been seen in that place
for nearly one hundred years, and some of the others for at
least thirty years. Their length and arrangement are constant,
or vary only between very narrow limits. Each of them always
begins and ends between the same regions. But their appear-
ance and their degree of visibility vary greatly, for all of them,
from one opposition to another, and even from ore week to
another, and these variations do not take place simultaneously
and according to the same laws for all, but in most cases
happen apparently capriciously, or at least according to laws
not sufficiently simple for us to be able to unravel. Often one
or more become indistinct, or even wholly invisible, whilst
others in their vicinity increase to the point of becoming con-
spicuous even in telescopes of moderate power.

Every canal ' (for now we shall so call them) opens at its ends,
either into a sea, or into a lake, or into another canal, or else
into the intersection of several other canals. None of them
have yet been seen cut off in the middle of the continent,
remaining without beginning or without end. This fact is of
the highest importance. The canals may intersect among them-
selves at all possible angles, but by preference they converge
towards the small spots to which we have given the name of
lakes. For example, seven are seen to converge in Lacus
Phtenicis, eight in Trivium Charontis, six in Lunse Lacus, and
six in Ismenius Lacus.

The normal appearance of a canal is that of a nearly uniform
stripe, black, or at least of a dark colour, similar to that of the
seas, in which the regularity of its general course does not ex-
-elude small variations in its breadth, and small sinuosities in its
two sides. Often it happens that such a dark line opening out
upon the sea is enlarged into the form of a trumpet, forming a
huge bay, similar to the estuaries of certain terrestrial streams.
The Margaritifer Sinus, the Aonius Sinus, the Auroras; Sinus,
and the two horns of the Sab.xus Sinus are thus formed, at the
mouths of one or more canals, opening into the Mare Ery-
thr.-eum or into the Mare Auslrale. The largest example of
such a gulf is the Syrtis Major, formed by the vast mouth of the
Nilosyrtis, so called. This gulf is not less than 1800 kilometres
{ivx> miles) in breadth, and attains nearly the same depth in
■a longitudinal direction. Its surface is little less than that oi
the Bay of Bengal. In this case we see clearly the dark surface
of the sea continued without apparent interruption into that of
the canal. Inasmuch as the surfaces called seas are truly a
liquid expanse, we cannot doubt that the canals are a simple
prolongation of them, crossing the yellmv areas or continents.

Of the remainder, that the lines called canals are truly great
furrows or depressions in the surface of the planet, destined for
the passage of the liquid mass, and constituting for it a true
hydrographic system, is demonstrated by the phenomena which
■are observed during the melting of the northern snows. We
have already remarked that at the time of melting they appeared
surrounded by a dark zone, forming a species of temporary sea.
At that time the canals of the surrounding region become
blacker and wider, increasing to the point of converting, at a
certain time, all of the yellow region comprised between the
edge of the snow and the parallel of 60" north latitude, into
numerous islands of small extent. Such a slate of things does
not cease, until the snow, reduced to its minimum area, ceases

1 The correct Iransl.ilion of the Italian word idHrt/f, used with reference
to the streaks on Mars, is channel or strait, and not canal.

NO. 1308, VOL. S']

to melt. Then the breadth of the canals diminishes, the tem-
porary sea disappears, and the yellow region again returns to its
former area. The different phases of these vast phenomena are
renewed at each return of the seasons, and we have been able
to observe them in all their particulars very easily during the
oppositions of 1882, 1884, and 18S6, when the planet presented
its northern pole to terrestrial spectators. The most natural
and the most simple interpretation is that to which we have
referred, of a great inundation produced by the melting of the
snows — it is entirely logical, and is sustained by evident analogy
with terrestrial phenomena. We conclude, therefore, that the
canals are such in fact, and not only in name. The network
formed by these was probably determined in its origin in the
geological state of the planet, and has come to be slowly
elaborated in the course of centuries. It is not necessary to
suppose them the work of intelligent beings, and notwithstand-
ing the almost geometrical appearance of all of their system,
we are now inclined to believe them to be produced by the
evolution of the planet, just as on the Earth we have the
English Channel and the Channel of Mozambique.
The Gemination of the Canals.

The most surprising phenomenon pertaining to the canals of
Mars is their gemination, which seems to be produced princi-
pally in the months which precede, and in those which follow
the great northern inundation, at about the times of the equi-
noxes. In consequence of a rapid process, which certainly
lasts at most a few days, or even perhaps only a few hours, and
of which it has not yet been possible to determine the par-
ticulars with certainty, a given canal changes its appearance,
and is found transformed through all its length, into two lines
or uniform stripes, more or less parallel to one another, and
which run straight and equal with the exact geometrical pre-
cision of the two rails of a railroad But this exact course is
the only point of resemblance with the rails, because in dimen-
sions there is no comparison possible, as it is easy to imagine.
The two lines follow very nearly the direction of the original
canal, and end in the place where it ended. One of these is
often superposed as exactly as possible upon the former line,
the other being drawn anew, but in this case the original line
loses all the small irregularities and curvature that it may have
originally possessed. But it also happens that both the lines
may occupy opposite sides of the former canal, and be located
upon entirely new ground. The distance between the two lines
differs in different geminations, and varies from 600 kilometres
(360 miles) and more, down to the smallest limit at which two
lines may appear separated in large visual telescopes — less than
an interval of 50 kilometres (30 miles). The breadth of the
stripes themselves may range from the limit of visibility , which
we may suppose to be 30 kilometres (iS miles), up to more than
100 kilometres (60 miles). The colour of the two lines varies
from black to a light red, which can hardly be distinguished
from the general yellow background of the continental sur-
face. The space between is for the most part yellow,
but in many cases appears whitish. The gemination
is not necessarily confined only to the canals, but tends
to be produced also in the lakes. Often one of these is
seen transformed into two short, broad, ilark lines parallel to
one another, and traversed by a yellow line. In these cases
the gemination is naturally short, and does not exceed the limits
of the original lake.

The gemination is not shown by all at the same time, but
when the season is at hand, it begins to be produced here and
there, in an isolated, irregular manner, or at least without any
easily recognisable order. In many canals (such as the Nilo-
syrtis for example) the gemination is lacking entirely, or is
scarcely visible. After having lasted for some months, the
markings fade out gradually and disappear until another season
equally favourable for their formation. Thus it happens that in
certain other seasons (especially near the southern solstice of
the planet) that few are seen, or even none .it all. In different
oppositions the gemination of the .same canal m.iy present dif-
ferent appearances as to width, intensity and arrangement of the
two stripes, also in some cases the direction of the lines may
vary, although by the smallest quantity, but still deviating by a
small amount from the canal with which they are directly asso-
ciated. From this important fact it is immediately understood
that the gemination cannot be a fixed formation upon the
surface of Mars, and of a geographical character like the canals.

The observation of the geminations is one of the. greatest
difficulty, and can only be made by an eye well practised in

9°

NATURE

[November 22, 1894

snch work, added to a telescope of accurate construction and of
great power. This explains why it is that it was not seen before
1882. In the ten years that have transpired since that time, it
has been seen and described at eight or ten observatories.
Nevertheless, some still deny that these phenomena are real,
and tax with illusion (or even imposture) those who declare
that they have observed it.

Explanations of the Gemination of Canals.

Havins regard then to the principle that in the explanation
of natural phenomena, it is universally agreed to begin with the
slmi'lest suppositions, the first hypotheses on the nature and
cause of the geminations have for the most part put in opera-
tion only the laws of inorganic nature. Thus the gemination
is supposed to be due either to the effects of light in the atmo-
sphere of Mars, or to optical illusions produced by vapours in
various manners, or to glacial phenomena of a perpetual
winter, lo which it is known all the planets will be con-
denined, or to double cracks in its surface, or to single cracks
of which the images are doubled by the effect of smoke
issuing in long lines and blown laterally by the wind. The
examinaiion of these ingenious suppositions leads us to con-
clude that none of them seem to correspond entirely wiih
the observed faci-s either in whole or in part. Some of these
hypothcse.s would not have been proposed had their authors
been able to examine the geminations with their own eyes.

It is far easier to explain the gemination if we are willing to
introduce the forces pertaining to organic nature. Here the field
of plausible supposition is immense, being capable of making an
infinite number of combinations capable of satisfying the appear-
ances even w iih the sm.-illest and simplest means. Changes of vege-
tation over a vast area, and the production of animals, also very
small, but in enormous multiiudes, may well be rendered visible
at such a distance. An observer placed in the moon would be
able to see such an appearance at the times in which agricultural
operations are carried out upon one vast plain — the seed time j
and the gathering of the harvest. In such a manner also would i
the flowers of the plants of the great steppes of Europe and Asia
be rendered visible at the distance of .Mars— by a variety of
colouring. A similar system of operations produced in that
planet may thus certainly be rendered visible to us. But how
difficult for the Lunarian's and Areans lo be able to imagine the
true causes of such changes of appearance, without having first
at least some superficial kno« ledge of terrestrial nature ! So
also for us, who know so little o( the physical stale of Mars,
and nothing of its organic world, the great liberty of possible
supposition renders arbitiary all explanations of this sort, and
constitutes the gravest obstacle lo the acquisition of well-founded
notions. All that we may hope is that with time the uncertainly
of the problem will gradually diminish, demonstrating, if not
what the geminations are, at least what they cannot be. We
may also c jnfidc a lilllc in what Galileo called " the courtesy of
nature," lli.irks lo which, sometimes from an unexpected source,
a ray of light will illuminate an invesiigali.n at first believed
inaccc-sible to our speculations, and of which we have a
beautiful tx.Tnii-1c in celestial chemistry. Let us therefore hope
and »tu<K

EARLY lililTISH RACES}
\\.

IN continental caves human skeletons of this period have been
found; of these, pcihaps, the best known is the famous
Neanderthal one, from a cave near Diisseldorf. Upon this
skeleton alone it woulil not have been prudent to have base.l
the chaiacieis of I'.ilaioliihic cave men, because Ihe circum-
stances under which it was found have given rise to some
doubt ax lo in being of this age, and it is by some con-
sidered "o belong to the next period which we have lo deal
with. When it is taken in conjunction with others presenting
similar characlem, regarding which there is no doubt as to
the age lo which ihey belung, ihe evidence it affords is
consiiltrably Mrerglhcncd. The find of two skeletons at
Spey (in Hclgium) in 1886, has been most important, both in
advancing our knowledge and confirming ihe characters
ascrilicd 10 this race from various less complete specimens. The
cranium of the Neanderthal »kcleton, though very imperfect,
is long and pro|«irtionatcly n.nrrow in form, having a cephalic
index of 72, the glabella, brow ridges, and external orbital pro-
I Conliniicd from p. 7C^

cesses are enormously developed, the forehead is remarkably
fl.ittened, the occiput is prominent, and the elevation of the
whole vault is extremely low. The skulls of bolh the Spey
skeletons are also long and narrow, one having a cephalic
index of 70, and the other of 746 ; the superciliary ridges and
also the glabella are very prominent ; the frontal sinuses are
large, the external orbital processes are thick and projecting,
the ridges on the frontal, parietal, and temporal bones for
muscular attachments are strongly developed ; Ihe occiput is
prominent with a well-marked "torus" at the junction of the
curved muscular ridges, which are also large : the cranial vault
is low and llattened from above downwards, and presents an
antero-posterior curve very similar to the outline of the side of
an ellipse. The malar bones have thick and broad orbit.al
processes, the orbital cavities are deep, and the oviiilal breadth
is;but slightly inferior to the width ; the zygomatic arches are
large. The sire of the lower molar teeth increases from before
backwards, the first molar bting the smallest, and the wisdom
or last molar the largest. The lower jaw shows no prominence
of the chin ; indeed, it recedes somewhat from the alveolar
border downwards, and has a symphesial angle of ill". It is
thus a counterpart of the Naulette mandible, which presents
similar characters, bolh as regards the molars and symphesial
angle. The stature of the Neanderth.al skeleton, estimated
from the length of the femur, is I 604 metres (5 ft. 3 in.l, and
from the humerus 2 cm. less ; that of the Spey skeleton (there
being only one of these in which the long bones could be
measured), estimated from the femur and tibia, is i 504 metres
(4 ft. Ili in.), and from the femur alone, i'540 metres
(5 ft. o\ in.). The stature of the Naulette skeleton, that of a
woman, estimated from the ulna, is i"433 metres (4 ft. 4A in.),
and shows that she also was very short.

The long bones of bolh upper and lower limbs of the Neander-
thal skeleton are characterised by their unusual thickness, and
the great development of the elevations and depressions for the
attachment of muscles, the articular ends of the lemur are
also of larger size than usual. The femur of ihe Spey skeleton is
more arched forward than usual, it is somewhat llatlened from
side to side in section, and the articular ends are of large size,
especially the lower, in which there is enormous anteroposterior
development of the articular surface of the condyles. The
tibia is actually and proportion.ately very short, flattened later-
ally, and therefore plalycnemic. The bones generally are
remarkable for their sioutness, and indicate that the muscles
attached to them were large and powerful, especially those of
the lower limb. In respect to the plalycnemism of the tibia,
the Spey skeleton corresp nds to the Langcrie Hasse and Made-
lainc bones from the I'erigord Caves, and confirms in a very
positive manner the evidence of thtir surroundings and relicts
that Palreolilhic jieople were sons of the chase, as it is connected
with the development of the tibialis posticus muscle, and not a
race character.

Portions of skulls and skeletons found in various parts of the
continent, associated with Pal.-colithic implements and animal
remains of late Pleistocene limes, suppoit the peculiar race
characters of the specimens just described. The osieological re-
mains of Pal.-colilhicage now in hand from different pans of the
continent seem to me lo afford sufficient evidence of the exist-
ence, both in drift and in cave deposits, of a race of men
possessing physical characters quite distinct from those of the
Neolithic period, which we will next consider. The assertions
which have been made at various times wilh respect to indi-
vidual specimens being more or less pathological, will, to my
mind, not hold good when we fiml specimen alter specimen
from the same deposits showing similar characters. It may not
be possible, in some cases, to establish the fact that the speci-
men cannot have been deposited at a later period in the stratum
in which it is found, but a careful examination of each speci-
men, such, for example, as Prof. Topinanl has made of the
m.andilile from Naulette, shows anatomical conditions which,
not in one respect but in several, indicate as dislincllv as his
iinplcmenis the progress of man's evolution, ami preclude the
idea of this type being a variety ol the Neolithic people. The
specimens ol Pala;olilhic man seem lo me to show identity of
race, whether ihcy have been found in the river drift or in the
Palaroliihic stratum of caves. Ihe ideaol Prof, lioyd Dawkins,
that the implements found in the rivcrdi ids and later Palrco-
liihic deposits of caves, give evidence of lliere being two Pala;o-
lithic races, is not supported by the osieological remains yet to
hand. From extensive examination of ancient Hiilish skelelonF,

NO. TH08, vol. si]

November 22, 1894]

NATURE

91

I do not consider that there is any evidence of the existence of
the direct descendants of Palasolithic man amonj; the osteo-
logical remains of Neolithic or subsequent date in Britain.
Here he seems tojpe as extinct as many of his contemporary
animals of the late Pleistocene period ; this may not be the ca<e
with respect to his existence in other parts of Europe. Whether
he has still representatives in America, as surmised by I'rof.
Boyd Dawkins and some American anthropologists, is outside
the scope of the present lecture.

The next period at which we find remains of man in Britain
is separated from the previous one by a space of time measur-
able only by the changes occurring in the interval. Great Britain
and Ireland had once more become islands almost of the same
dimensions as at the present day, with a moister and more con-
tinental climate — hotter in summer and colder in winter — ■
abundant forests extending as far as the extreme north of Scot-
land, and numerous morasses and peat bogs. Not less signi-

From these camps have been obtained spindle whorls and
bone combs toothed at one end, showing that they were
acquainted with the arts of spinning and weaving, bone
needles, fragments of coarse pottery, made by hand and
not turned on the wheel, either plain or ornamented with
simple lines or dots, bones of the roe, red deer, dog, goat,
short-horned ox, horse, pig, &c. , and fish, but no trace of metal
is found. Of all their implements the stone axe is perhaps the
most important. P'lints used for implement-making were now
often quarried from below the soil, with antlers of deer as picks.
The implements were distributed over districts far removed
from where they were m.ide, probably by barter, Jadite or
Nephrite implements having been found in Britain, which Mr.
Kudler has shown may have been obtained from Switzerland,
Silesia, or Styria. They possessed canoes formed out of the
trunks of trees, in which they probably reached this country
from the continent.

iralktr fri;,^,.

Fig. j6.

ficant was the advance in civilisation man had made since
Palfcolithic times, as we now find him dwelling in fixed habita-
tions, with a knowledge of the arts and agriculture, with
domestic animals, and with stone implements of a much more
developed character, as he had now learned to smooth them by
grinding and polishing.

The^e Neolithic people, as they are called, lived in camps,
surrounded by ditches and ramparts, on the to| s or sides of
hills, or in suitable valleys. The camps were intersected with
numerous drains or ditches, which would show that the
climate was moist. Inside the camps they hollowed out pits,
in or round which they dwelt. Excellent examples of the
encampments or villages of the same Neolithic people, but of
a much later date, have been discovered and described by
General Pitt-Rivers in his excavations near Rushmore, from
the main outlines of which some idea may be formed of what
their earlier dwelling-places were probably like (Fig. i6).

NO. 1308, VOL. 5 ll

They buried their dead in caves, which had been used a
dwellings, in their camps, and in chambered and unchambered
barrows. The most characteristic British barrows of this period
are of long oval shape, and often of large size, but Neolithic
interments are also found in circular barrows. The dead were
buried in a contracted or crouched position, and with ihem,
stone and bone implements of various kinds, and pottery, which
would seem to show that these articles were intended for the
use of the dead or their spirits. Relics of art in the form of
carvinijs are seldom fuund, and are very inferior to those of late
PahTiolithic times.

O.-teological remains of the Neolithic people are distributed
all over Britain, from the south of England to the extreme north
of Scotland. They are most numerous in the south-west of
England, especially in Wilts and Gloucestershire, the part of the
country occupied by the Drobuni, or Silures, at the beginning
of the historic period. They have been foundjin considerable

92

NA TURE

[November 22, 1S94

numbers in Yorkshire, Derbyshire, and Stafford. Huxley and
Wilson have describe I ihe same race from horned cairns in
Caithness, and (roin other places of Scotland. I havedesciibed
them from Wiltshire, Yorkshire, Middlesex, and from Orkney.
There is some doubt of their having been found yet at an
early period in Ireland, as Prof. Macalister informs me that he
has not recognised them in Ireland, where there are no long
barrows. Sir William Wild, on the other hand, recognised
Neolithic skulls from Somersetshire as identical with certain
ancient Irish skulls. Any skulls from Ireland I have seen,
which have shown characters similar to the Neolithic skulls
from England, are of later date, but Huxley describes them from
ch.imbered touibs, peat mosses, and river deposits of Ireland.
I iliink we may conclude, as regards Ireland, that although it
is doubtful whether the Neolithic people were there at as early
a date as in Britain, ihey were certainly there later.

The characters of the skeletons are well marked. The skull
is large and well formed, the calvaria is long and proportionally
narrow, having a cephalic index of about 70. and of oval shape.
The superciliary ridges and glabella aie moderately or even
feebly developed, the forehead is well formed, narrow, and
curves gracefully to the occiput, which is full and rounded.
The upper margins of the orbits are thin, and the malar bones
are never prominent ; the profile of the face is vertical, and
there is no tendency to piognathism ; the chin is prominent,
the symphesial angle is from 70° to So° ; the length of the face
from the root of the nose is comparatively short, but as a whole
the face is oval in form ; the jaws are small and fine, the teeth
are of medium size, and generally in a good stale of preservation,
not much worn down. The last molar is always the smallest
tooth of that seiies. The facial characters are mild, and
without exaggerated development in any one direction ; the
same may be said of the calvaria generally. The age of the
persons to whom they belong averages, according to Thurnam,
forty-five years, which would seem to indicate that the duration
of life was rather short at that time.

The stature of the Neolithic people is short. From Dr.
Thurnam's measurements of the femora of twenty-five skeletons,
i; averages I 674 m. (5ft. bVm.) by Rollet's formula ; but from
my own observations of other specimens which have parsed
through my hands, I am inclined to consider this as too high an
average. In their general characters the bones are slender,
often with a well-marked linca aipera on the femur and plalyc-
nemic tibia, which would show that the Neolithic people led
an active life, probably as hunters. Dr. Thurnam has noted
that sometimes two or more of the cervical or dorsal vertebra-
have a tendency lo anchylosis, but I cannot say I have ever seen
this.

On the continent of Europe remains of the Neolithic people
arc found chiefly in caves, and show much the .'-ame state of
culture and physical features as just described, for instance the
well-known Cro-.Magnon race ; but the sequence of their
existence there is not so well defined as in Britain, where they
held apparently undisputed possession of the country for a
considcralile period. Indeed, it is only lately that continental
anthropologists have admitted their priority to that of people
presenting the character of the next race we will have to deal
with.

From the evidence to hand, it seems probable that the
Neolithic people occupied the whole of the west of Europe at
one time ; and I agree with several observers in considering that
they are to be ideniified with the old Iberian race, of which
the Bas'jue may be considered a remnant. There is certainly
a strong similarity between Basque skulls and those of the
Neolithic people of Britain.

Unlike I'ala;olithic man the Neolithic people have never be-
come extinct in Britain, and their descendants exist to the pre
sent time. It is true that subsequent invaders drove them, in
many instances, to particular pans of the country, as early
history and the excavations of General ritt-Kivers and others
show ; but skeletons from ancient tombs indicate that they also
mixed with their cor.querors.

The next people 10 appear upon the scene, previous to the
dawn of history, aie those who were in possession of the
greater pan of Britain at the lime of Ihe Roman invasion.
They came into Bmain from France and Belgium at a consider-
ably earlier period, and subjugated or displaced the Neolithic
race. These are the so-called Cells. Their advent is marked by
the inlroduciion of Ihe use of metals into Britain, and Ihey are
associated with the Bronze age. From the custom Ihey had

NO. IjCS, VOL. 5 l]

of interring their dead, whom they chiefly cremated, in barrows
of a circular shape, they are often known as the Round Barrow-
people. They show- a marked advance in civilisation beyond
that of Neolithic times, as they were agriculturists, and lived
by tilling the soil : they manufactured weapons and ornaments
of bronze, and richly decorated pottery ; their flint implements
also were of better make, as evidenced by their beautiful
barbed arrow-heads. To this period belong many of the
curious lake dwellings found all over Great Britain and Ireland,
Picts houses of Scotland, and bee-hive houses of Ireland.

Their osleological remains show lh.it the skull «-as large with
strongly-developed superciliary ridges and glabella, the brow
well formed and broad, the upper occipital region not project-
ing, Ihe tuberosity being the most prominent. In general form
the brain-case is broader and rounder than in the Neolithic
race, the cephalic index centring round Si ; they were, there-
fore, a distinctly brachycephalic people. The upper border
of the orbit is thick, the malar bones are prominent and large.
The jawbones are large, n:aci\y:;nat'ioiii, and likewise the
teeth, which are often much ground down ; the profile of the
upper jaw is somewhat prominent, which gives a progna-
thous look to the skull ; the chin is well formed. The face
as a whole is of an angular lozenge form. The ridges for
muscular attachments, both on the cranium and face, are well
developed, and the expression is very rugged and savage-like.
From the skull Thurnam estimated the average age of the per-
sons interred in the round barrows was fifty-live years, while
that of the long barrows was ten years less.

The stature of the Round Barrow race averages I '747 metres
(5 feet 9 inches), which is more than the mean stature of the
population of the British Isles at the present day. The limb
bones are large, with strongly-developed ridges and depressions
for muscular attachments.

This race i< everywhere to be found over Great Britain and
Ireland, and although conquered by ihe Romans and subsequent
invaders, forms a very important element of the population of
the country down to the present day.

[I have to ihank I'rof. Boyd Hawkins for his kind permission
to use woodcuts from his work on " Karly Man in Britain," for
the purpose of illustrating this publication of my lecture, and
to General Pitt-Rivers lor permitting the reproduction of a
block from his plate in "Excavations near Rushmore," vol. ii.
The lecture, as delivered at the Royal Institution, was illustrated
by numerous lantern slides, which were not suitable for
reproduction.]

UNIVERSITY ASD EDUCATIONAL
INTELLIGENCE.

Oxford. — The Statute relating lo Research Degrees has been
promulgated, and has given rise to some dissatisfaction among
many of those who have hitherto warmly supported the scheme.
The supervision of those who wish to qualify for a Research
Degree is to be placed, according to th-_- proposed Statute, in the
hands of a Delegacy composed of the Vice-Chancellor and
Proctors and twelve other member?, to be nominated by the
Vice-Chancellor and Proctors, the llebdomadai Council, and
the Members of Congregation This amounts to the creation of
a new Delegacy similar in constitution and in powers to the ex-
isting Delegacy of non-collegiale students, and it is felt that it i.-.a
most unsuitable mode of supervising the work of men none cf
whom may be less than twenty-one years of age. It was thought
that the supervision of the researchers should be vested in the
Professorial body, and it is much to be hoped that the proposed
Statute will be thrown out in Congregation, for it is nearly
certain that no persons qualified for research would submit
themselves lo the supervision of such a heterogeneous body as
the proposed Delegacy, and the scheme, of which so much is
expected, would become a dead letter.

In a meeting of ihc Junior Scientific Club, held on Friday,
November 16, Mr. P. Flford, of St. John's, exhibited a specimen
of shale oil, and papers weic read by Mr. F. Dtuce, of Magdalen
College, on anticyclones and other types of atmospheric
pressure, and by Mr. W. W. Fisher, of Corpus Christi College,
on the Oxford water s-jpply.

Mr. P. L. Sclater, F.R.S., has been elected an honorary
Fellow of Corpus Christi College.

NoVE.MliER 22, 1894J

NA JURE

Cambridge. — Dr. Forsyth, F.K..S., has been appointeil
Chairman cjf=the Examiners for I'art II. of the Mathematical
Tripos.

Mr. E. H. Ilankin, Fellow of St. John's College, and Pro-
fessor ol Bacteriology at .\s;ra, has been appointed lo represent
the University at the Indian Medical Congress to be held at
Calcutta in December.

The following is the Syndicate appointed to consider a repoit
in the question of special encouragement, by new degrees or
'therwise, for post-yraduale study and research in the University :
Ihe Vice-chancellor, Dr. Maiiland, Dr. D. Macalitter, Dr.
Jebb, Dr. Forsyth, F.R.S., Prof Marshall, Prof. Gwatkin,
Prof. Foster, F.R.S., Prof. Thomson, F.R.S., Mr. A. \V. \V.
Dale, of Trinity Hall, and Mr. W. Bateson, F.R.S., of St.
John's College.

A Grace authorising the Cavendish Laboratory Syndicate lo
obtain specifications and tenders for the proposed extension of
the Laboratory, was offered to the .Senate on November 22.

SCIENTIFIC SERIALS

American /ournal 0/ Siiiiicf, November. — On variations and
mutations, by W. B. Scott. The author discusses the problem
of animal morphology in its various aspects, and the different
lines along which a solution has been sought for. These are
that of comparative anatomy, embryology, and paU,;ontology,
to which, since Bateson's work on the study of variation, a
fourth has been joined. The author criticises in detail Bate-
son's method and its results, and comes to the conclusion that
we can no longer assume as a fundamental and self-evident
truth that individual variations are the material from which new
species are constructed. — Resonance analysis of alternating
currents, by M. J. Pupin. This analysis is performed by means
o( a " resonator circuit" consisting of an inertia coil, a rheostat
and a condenser in shunt with an electrostatic voltmeter. The
capacity of the condenser is gradually increased from zero
upwards. Whenever a capacity has been reached, which with
the self induction of the resonator circuit produces resonance
with one of the harmonics in the main circuit, then the reson-
ant rise of potential produces a large deflection in the voltmeter.
In this manner all the harmonics which are present in the
current of the main circuit can be detected in a few minutes. —
On some new methods of obtaining platinochlorides, and on
the probable existence of a platinum subchloride, by .M. Carey
Lea. One of the new methods employs potassium acid
sulphite, with a solution of which potassium platinic chloride
is moderately heated. The reduction takes about ten to twelve
liours, and is known to be complete when the solution has
a pure red colour free from yellow. The second method is
that with alkaline hypophosphites. If in obtaining potas-
sium platinochloride with the aid of a hypophosphile in
excess, the heat is continued after complete conversion to the
red salt, the solution in a few minutes changes from red
:o dark brown. The substance which gives the solution this
dark brown colour is very deliquescent, and cannot be crystal-
lised. It cannot be completely separated from the other
substances in solution. The author is led by its reactions to
suspect that it is a subchloride of platinum, analogous to that of
silver.

lounial of Anatomy and Physioh\^y, October. — Dr.
Gustav Mann, in a paper entitled "Histological Changes
induced in Sympathetic, Motor and Sensory Nerve Cells
by Functional .\ctivity (preliminary note)," gives an .iccount
of experiments made by him to test the observations of
Hodge and F. Vas. Dr. Mann's observations relate to
the cervical symp.ilhetic ganglia (which also formed the
subject of F. Vas's investigations), the motor area of the
cerebrum, and to the retina and optic centres of the brain. His
results in part agree with thise of Hodge, in part with those of
Vas, but they also in other particulars go beyond both. He
considers that he has placed beyond doubt, that: (i) During
rest, several chromatic materials are stored up in the nerve cell,
■ind that these materials are used up by it during the perform-
ance of its function. (2) .Activity is accompanied by an in-
crease in ^ize of the cells, the nuclei, and the nucleoli of
sympathetic, ordinary motor and sensory ganglionic cells. (3)
Fatigue of the nerve cell is accompanied by shrivelling of the
nucleus, and probably also of the cell, and by the formation of a
diffuse chromatic material in the nucleus.

NO. 1308, VOL 51]

SOCIETIES AND ACADEMIES
London.

Royal Society, November 15. — " On the Ascent of Sap."
By Henry H, Dixon, .-Assistant to the Professor of Botany,
Trinity College, Dublin, and Dr. J. Joly, F.R.S.

Slrasburger's experiments have eliminated the direct action of
living protoplasm from the problem of the ascent of sap, and
have left only the tracheal tissue, as an organised structure, and
th e transpiration-activity of the leaf wherein to seek an explana-
tion of the phenomenon. The authors investigate the cap-
abdity of the leaf to transpire against excessive atmospheric
pressures. In these experiments the leaf was found able to
bring forward its water meniscuses against the highest pressures
attained and freely transpire. Whether the draught upon the
sap established at the leaf during transpiration be regarded as
purely capillary or not, these experiments lead the authors to
believe that it alone is quite inadequate to effect the elevation by
direct tension of the sap in tall trees. Explanations of the
lifting of the sap from other causes prove inadequate.

K reconsideration of the principal experiments of previous
observers and some new experiments of the authors lead to the
view that the ascent is principally in the lumen and not in the
wall.

The explanation of how the tensile stress is transmitted in the
ascending sap without rupture of the coluinn of liquid is found
in the stable condition of this liquid. The stale of stability
arises from two circumstances : the internal stability of a liquid
when mechanically stretched, whether containing dissolved
gases or not, and the additional stability conferred by the
minutely subdivided structure of the conducting tissue, which
renders the stressed liquid stable even in the presence of free
gas.

By direct experiments upon water containing large quantities
of dissolved air, the state of internal stability is investigated
And, further, by sealing up in the vessels, in which the water to be
put under tension is contained, chips of the wood of Taxus
Inucata, the authors find that their presence in no case gives
rise to rupture of the stressed liquid, but that this occurs prefer-
ably anywhere else, and usually on the gl.oss walls. The estab-
lishment of tensile stress is effected in the usual way, by cooling
the completely filled vessel. A measurement possessing con-
siderable accuracy afforded '\ atmospheres as being attained in
some of the experiments.

The second condition of stability arises directly from the
property of the pit-membranes to oppose the passage of free
gas, while they are freely permeable to the motion ol a liquid.
Hence a chance development of free gas is confined in effect
to the minute dimensions of the compartment in which it is
evolved, and this one lumen alone is rendered for the time being
non-conducting. On the other hand, in the water-filled portion
of the tiacheal tissue, the closing membranes, occupying the
median and least obstructive position, the motion of the stress
sap is freely allowed. The structure of the conducting tissue
is, in fact, a configuration conferring stability on a stressed
liquid in I the' presence (from various causes) of free gas.
.\s neither free gas nor unwetted dust particles can
ascend with the sap, the authors contend that the state of
tensile stress necessary to their hypothesis is inevitably induced.

The energy relations of the leaf with its surroundings, on the
assumption that evaporation at capillary water-surfaces is
mainly responsible for the elevation of sap, may be illustrated
by the well-known power of the water-filled porous pot to
draw up mercury in a tube to which it is sealed. The authors
describe an engine in which the energy entering in the form of
heat at the capillary surfaces may be in part utilised to do
mechanical work : a battery of twelve small porous pots, freely
exposed to the air, keeping up the continuous rotation of a fly-
wheel. Replacing the porous pots by a transpiring branch,
this too maintains the wheel in rotation. This is, in fact, a
veget.nble engine. In shoit, the transpiration effects going on
at the leaf are, in so far as they are the result of spontaneous
evaporation and uninfluenced by other physiological phenomena,
of the "sorting demon " class, in which the evaporating surface
pl.ays the part of a sink of thermal energy.

If the tensile stress in the sap is transmitted to the root, the
authors suggest that this will establish in the capillaries of the
root surface meniscuses competent to condense water rapidly
from the surrounding soil. They show by experiment the power
possessed even by a root injured by lifting from the soil, of con-
densing water vapour from a damp atmosphere. Such a state

94

NATURE

[November 22, 1894

of Ihiogs may be illustrated by a system (which the authors
realised) consisting of two porous pots connected by a tube and
all filled with water ; one, the " leaf," exposed to the air gives
out vapour, the other, the "root," buried in damp earth sup-
plies the demand of the "leaf," and an upward current in the
connecting tube is established.

"Further Obseivations on the Organisation of the Fossil
Plants of (he Coal-Measures. Part ii. The Roots of Ca/<i»/;V«."
By Dr. W. C. Williamson, F.R.S., and Dr. D. H. Scott,
F.R.S.

The conclosioDS at which the authors arrive are the follow-
ing :—

(1) The fossils hitherto described under the name of
Aittomyilon WUIiamsonis are the adventitious roots of
CalarniUs.

(2) Their structure is in all respects that characteristic of
roots, as is proved by the centripetal primary wood, the alter-
naling strands of primary wood and phloem, the endogenous
mode of branching, and the absence of nodes.

(3) The smallest specimens, with little or no medulla,
represent the finest branches of the same roots, of which the
large medullate forms are the relatively main axes.

Linnean Society, November i. — Mr. C. B. Clarke, F.R.S.,
President, in the chair. — Mr. .\lexancler Whyle was admitted.
— Messrs. H. and J. Groves exhibited an undescribed C/;a/afrom
Wesimcilh, and made remarks upon its peculiar mode of
growth. — Mr. J. O. Tepper exhibited photographs of a new and
remarkable fungus from .South Australia, Laccocephalum liasi-
lafiloides, which explained the formation of the peculiar stone-
like nodules occasionally found when clearing scrub-land.
These were found to be due to the agglutinating nature of the
mycelium of this fungus, the grains being permanently cemented
by lime and ferruginous oxides. — The Rev. G. llensiow made
some remarks on a peculiar mode of propa;;ation of Oxalis
ceriitiat observed in Malta, and exhibited some views taken
during his sojourn here. — Mr. Miller Christy exhibited a long

f)iece of leaden pipe which had been gnawed through its entire
ength by rats, in a manner which showed that the object was
not, as generally supposed, to get access to water. — Mr. II. M.
Bernard exhibited some photographs of corals taken with the
"Kodak "camera. — Aseriesof that remarkable beetle Golinthus
giganteus, from West Africa, was shown by Dr. Ileath, and
Mr, E. M. Holmes exhibited son:e plants from Japan. —
On behalf of Mr. A. W. Waters, a paper was then read on
Mediterranean and New Zealand Retipora and on a fenestrate
bryozoan ; and on behalf of Dr. J. .Miillcr, a paper on certain
lichens in the Kew Herbarium.

Zoological Society, November 6. — Sir W. H. Flower,
K.C.B.,, F.R.S., President, in the chair. — The President read
a letter addressed to him by the late Emin P.aslia, containing a
diary of ornithological ob.scrvations made during the last part
of his journey towards the Congo. This letter and journal had
been taken from the Arabs on the Upper Congo by the officers
of the Congo F"rce State, and forwarded to the President. — A
communication from Mr. F. E. Blaauw, contained some re-
marks on the colour of the bill in a living specimen of Cygniis
aiiieridipiui. — A communication was read from Mr. K. Trimen,
containing a reply to .-ome remarks of Dr. A. G. Butler on his
paper on the Manica Butleidies collected by Mr. .Selous. — A
communication «a read from Dr. R. W. .Shufeldl, containing a
correclion to his paper on the affinities of the SUganopodes,
recently published in the SocKiy'i Proceedings. — Mr. <). Salvin,
F. R.S., exhibited a pair of the newly described butterfly
Ontitlwflera faroilisea, from the Finistcrre Mountains, Ger-
man New Guinea. — Mr. C. Davies Sherbotn exhibited a copy
of, and made remarks on the recently issued reprint of George
Ord's "American Zoology." — Mr. G. A. Boulenger, F.R.S.,
exhibitc I a Gecko, forwarded to him by Mr. R. T. Lewis,
which had been captured in winter (July), fully active, on the
snow U|>on the highest portion of the Drakcnsberg Range,
Natal. It lielongcd to a genus believed until 1888 to be
characteristic of the Australian fauna, and differed from its
nearest ally, (Eiiiira it/riaina, in the smaller and convex
f^nules covering the head and in the rostral shield not enter-
ing the nostril. Mr. Boulenger proposed for it the name
ir.iiutii utvaria. — Mr. M.irlin jacoby read descriptions of some
new species of the genus (liiiioiiyiliis and allied genera of
Coleoplera. — Mr. W. G. Kidcwoid read a paper on the hyoid
arch of Ceralodui. The author instituted a comparison between

NU, 1308, VOL. 51]

the ventral elements of the hyoid arch of Ceratodus and the
basi- and hypo-hyal cartilages of the Elasmobranchii. The
relations of the hyomandibular cartilage were dealt with in
detail, and attention was called to the wide range of variation
which this vestigial cartilage exhibits. Arguments were also
adduced to show that there is no connection between the re-
duction of the hyomandibular in the Dipnoi and its adaptation
as a secondary suspensorium in the hyostyllc fishes. — Mr. G.
A. Boulenger, F.R.S., read a third report on additions to the
Batrachian Collection in the Natural History Museum, con-
taining a list of the species, new or previously unrepresented, of
which specimens had been added to the collection since 1S90,
and descriptions of some new species. — A communication was
read from Mr. R. J. I.echmere Guppy. containing an account of
some Foraminifera from the microzoic deposits of Trinidad. —
A communication was read from Sir W.alter L. Buller, contain-
ing remarks on a petrel lately described as new by Captain
Hulton, under the name of (F.slrela/a tcucophrys.

Geological Society, November 7. — Dr. Henry Woodward,
F.R.S. , President, in the chair. — Sir John I.ubbock exhibited
some interesting specimens from the valley of Lauterbrunnen at
Murren. The rock forms part of the calcareous strata which
stretch to the southwest to Leuk, and to the north-east to the
celebrated gorges of the Aar. It has also a great thickness,
and is coloured in the geological map of Switzerland as
Malm, though some Swiss geologists have recently attributed
it to the Trias. Notwithstanding the careful researches of the
Swiss geologists no fossils, however, had yet been found in it.
During one of the recent excursions of the International
Geological Congress, Sir John Lubbock found a Layer which is
rich in fossils — amongst others Nummnlilcs Ramondi, Orl'itoides
disfaresus ?nd OrHloides tapyiaieus. The rock therefore is
not Malm, but Eocene. The species have been verified by Prof
Rupert Jones. Sir John Lubbock showed the spot to Prof.
Etheridge, who also exhibited some fossils from the same layer.
The find will necessitate a substantial correction of the
geological map, and is perhaps the more intcre-ting because
the specimens were found in a quarry by the roadside in the
village of Murren, and actually between the two principal
hotels. — Notes on some recent sections in the Malvern Hills,
by Prof. A. H. Green, F.R.S. The sections described occur
on the east side of the Herefordshire Beacon, and for con-
venience are named the Warren House Rocks. They are
bedded, and have a general north-andsouth strike. The great
bulk of the rocks are hard, close-grained, and spilinlety, and
are largely altered, and in many cases thickly veined with
calcite. Details of their structure were given ; and the author
stated that he is inclined to regard them as a group of bedded
acid lavas and tuffs, crossed by three bands of dolerite. What
little balance of evidence there is seems to be in favour of the
intrusive character of the dolerites. No true limestones have
been found, and the only very calcareous rock seen is regarded
as a rock belonging to the volcanic group which h.as been
largely calcified. A discussion followed, in which Mr. Watts,
Dr. Hicks, Mr. Rutley, and Mr. Harker took part. — The
Denbighshire series of South Denbii;bshire, by Philip Lake.
The area to which this paper chiefly referred is the south
western quarter of the Llangollen basin of Silurian rocks.
The t>eds are there very little disturbed, and the sequence was
readily made out. On comparison with other aieas it was
found that the .succession is almost identical with that in the
Long Mountain, in North Denbighshire, and in the Lake
di-tiict. Prof. Hughes, Mr. Ilopkinson, Dr. Hicks, Mr.
Marr, and Mr. Walts ni.i<le a few remarks upon the subject of
the paper. — On some points in the geology of the Harlech
area, by the Rev. J. F. Blake.

Entomological Society, November 7.— Colonel Charles
Swiidioe, Vice-1'residenl, in the chair —Colonel Swinhoe ex-
hibited a female of Pafilio leteaichus, Hewitson, which he had
leceived by the last mail from Cherra Punji. He said that this
was the only known specimen of the female of this species, with
the exception of one in Mr. L. de Nici'ville's collection, which
he had described in the ^oh'ho/ of the Bombay Natural History
Society in 1893. He also exhibited a male of the same species
for comparison. — Mr. C. G. Barrett cxiiiliitcd abnormal forms
tif Paran;e mtgitra, P. <rgeiia, Melilea alhalia, Chrysophanus
fhlaai, Chaiirasgraminis, l.ophoplery.xeanutina, i'lusia gamma,
CxKullia chamomilliT, Poarmia iepaiid,ila, var. coiiversaria, and
other specie.', all collected by Major J. N. Still on Dartmoor,

November 22, 1894]

NATURE

95

Devon. He also exhibited for Mr. Sydney Webb, of Dover,
a longj series of most remarkable varieties of Arctia ca/a^ and
Arctia villica. — Mr. Gervase F. Matthew, R.N., exhibited
seven beautiful and striking varieties of Arctia villica, bred
from larvK obtained on the Essex coast, near Dovercourt, in
March and April 1893 and 1894. — Ilerr Jacoby exhibited two
specimens of [Slaps miurotiatus, with soft elytra, taken on a
wall at Hampstead. The Rev. Canon Fowler and Mr. G. C.
Champion made some remarks on the subject of the elytra of
immature l)eetles.— Mr. H. Goss exhibited a specimen of
Periplaneta aiistralasii£, received from Mr. C. E. Morris, of
Preston, near Brighton. Mr. McLachlan said the species had
been introduced into this countr)', but was now considered a
British insect. — Mr. B. G. Rye exhibited specimens of the
following rare or local species of Coleoptera, and gave the
names of the localities in which they had been taken :
Cicindela g^rmanica, Ettmicnis riifus, Triarthron markeli,
Mfzium affine, Homaloplia ruricola, Anomala frischi, var.
jtilii, Synapliis Jiliformis, Lixus pnrapUcticus, Balaninus
cerawrum, Asemtim striatum, and Ziugophora Jlavicollis.—yit.
McLachlan exhibited for Mr. G. C. IJignell two new species
of Ichneum.inida;, from Devonshire, viz. Pimpla liriJ;;mani,
Bign., a para-ite on a spider, Drasstis lapidicolens, Walck., and
Pracm absinthii, Bign., a parasite on Siphonophora absinthii,
Linne. — Mr. C. O. Waterhouse stated that the Acridium re-
ceived from Captain Montgomery, and exhibited by Mr. Goss
at the last meeting, was Acridium septemfasciatum, and he ex-
hibited the species with the wings extended. — Mr. Ridley
exhibited a species of a scale insect (? Lecanium) found on a
nutmeg tree in Malacca, and made some remarks on Formica
smaragdina,, which makes its nest on the trees, joining the
leaves together by a thin thread of silk at the ends. The first
step in making the nest is for several ants to bend the leaves
together and hold on with their hind legs, and one of their
number after some lime runs up with a larva, and irritating
it with its antennae, makes it produce a thread with which the
leaves are joined ; when one larva is exhausted a second is
fetched, and the process is repeated. — Mr. Waterhouse read a
paper entitled "Some remarks on the Antennae of Insects."
A discussion followed, in which Messrs. Champion, Jacoby,
McLachlan, and Gahan took part.

Mathematical Society, Novembers. — Mr. A. B. Kempe,
F.R.S., President, in the chair. — At this meeting, which was
the first held since the incorporation of the Society, the by-laws,
which had been drawn up by the council, were passed unanim-
ously. The ballot was then taken, and the gentlemen whose names
were published in Nature (November i, No. 1305, p. 19)
were declared duly elected to form the new council and officers.
The new President (Major Mac.Mahon, F.R.S.) having taken
the chair, Mr. Kempe read his address, the title of which was
"Mathematics." Other communications made were — a general-
ised form of thehypergeometric series, and the differential equa-
tion which is satisfied by the series, F. H. Jackson ; third (and
concluding), memoir on certain infinite products, Prof. L. I.
Rogers ; on the kinematics of non-Euclidean space. Prof. W.
Burnside, F.R.S.

Royal Microscopical Society, October 17.— The Rev.
Edmund Carr in the chair.— Dr. W. II. Dallinger, F.R.S.,
described a new model microscope which had been made by
Messrs. Watson. — Messrs. Ross exhibited examples of their
"Eclipse" microscopes. — Mr. R. T. Lewis exhibited some
parasites which had been found upon |a penguin from Isipingo,
Durban. — Ur. H. Stolterfoth's paper on the genus Cortthron
was read by Prof. Jeffrey Bell.— Mr. E. B. Green read a paper
on some parasitic growths on the root-hairs of plants. Mr.
A. W. Bennett made some remarks on Mr. Green's paper. —
Prof. Bell called attention to the loss the Society had suffered
by the death of Dr. G. E. Blenkins, a former secretary. — Mr.
F. Chapman gave a rlsiimJ at part of his paper on the Fora-
minifera of the Gault of Folkestone. The chairman and Prof.
Bell made a few remarks on Mr. Chapman's contribution. —
Owing to the absence of the author, Mr. Nelsoii's paper, on the
measuring of the refractive indices of various media, was deferred
to the next meeting on November 21.

Cambridge.
Philosophical Society, October 29.— Prof. T. McKenny
Hughes, President, in the chair. — The officers for the ensuing
session were elected as follows :— President : Prof. J. J. Thom-
son. Vice-Presidents : Prof. Sir G. G. Stokes, Prof. Hughes,

NO I " VOL. 51]

Mr. F. Darwin. Treasurer: Mr. Glazebrook. Secretaries:
Mr. I. armor, Mr. Newall, Mr. Bateson. New Members of
Council : Dr. Glaisher, Prof. Ewing, Mr. F. H. Neville, Mr.
E. II. Gr.ffiihs. Mr. W. B. Hardy, Mr. H. F. Baker. The
retiring President, Prof. Hughes, before vacating the chair,
addressed the Society. The President elect. Prof. Thomson,
on taking the chair, referred to the loss sustained by science in
the death of Prof, von Helmholtz. — Note on geometrical
mechanics, by Prof. Sir Robert S. Ball. — On a model of
the twenty-seven lines on a cubic surface, by Mr. W. H.
Blythe. Mr. Blythe exhibited a model of the twenty-
seven straight lines on a cubic surface, together with the draw-
ings from which it was constructed. He stated that the 135
points of intersection of these lines can, in a special case, be
determined by a simple geometrical construction without refer-
ence to any equation. Seven points taken at random on the
edges of a tetrahedron are sufficient to give values to all neces-
sary constants, and these points acting as pointers by pairs, fix
the position of eleven other points ; these eighteen points being
used to determine others, and so on. This method is also
applicable to the general case, but determines fifteen lines only ;
when however the sixteenth line or one point on it is fixed by a
process of adjustment the remaining points can be found in the
same way. — ^Exhibition of some photographs showing the marks
made by stars on photographic plates exposed near the focus of
a visual telescope, by Mr. H. F. Newall.

Paris.
Academy of Sciences,, November 12. — M. Loewy in
the chair. — The President announced the death of M. Duchartre,
and an account of this botanist's life and works was delivered
by M. Bornet. — On the transit of Mercury, by M. J. Janssen.
Owing to unf.-ivourable weather, only a part of the transit was
observed at Paris. — Researches on the condensation of electro-
lytic gases by porous bodies, particularly by metals of the
platinum group ; applications to the gas battery ; electric accu-
mulators under pressure, by MM. L. Cailletetand E. Collardeau.
Platinum and pr.lladium in the spongy condition, and ruthenium,
iridium, and gold in the finely divided state form poles which
condense electrolytic gases, and hence produce a gas battery,
on subsequent connection of the poles, capable of giving up
the stored energy during a short time. The storage capacity
may be vastly increased by subjecting the poles to great pressure
during charging. With spongy platinum and iridium a storage
capacity may be attained greater than the practical capacity of
lead accumulators per unit weight. Silver, tin, nickel, cobalt,
and carbon do not form accumulators under these conditions
with capacity increasing with the pressure. — New details con-
cerning .the Nymphaiin^ of the Lower Cretaceous system,
by M. G. de Saporta. — A study of the causes of saline
digestion, by M. A. Dastre. Saline digestion is not due
to the action of soluble ferments, and is not caused by
microbes. — On the disappearance of the southern polar spot
of Mars, by M. G. Bigourdan. — The transit of Mercury,
by M. E. L. Trouvelot. (See our Astronomical Column.)—
Onan error detected in the " theory of numbers" of Legendre,
by .M. Dujardin. — On the representation of left-handed
algebraical curves and on a formula by Halphen, by M.
Leon Autonne. — On an empirical formula, by M. Per-
vouchine, by .M. Ernest Ces,iro.— Direct experimental deter-
mination of the specific heat of saturated vapour and of the
heat of internal vaporisation, by M. E. Mathias. The general
method given permits, by means of a double series of calori-
metric experiments with an apparatus charged once for all, of
the complete resolution of the problem of the calorimetric
study of a substance, and shows that the .specific heat of satu-
rated vapour is susceptible of direct experimental determina-
tion.—Determination of the molecular weight of liquids, by M.
Ph. A. Guye. The author gives methods of determining mole-
cular weights of substances from a knowledge of their critical
coefficients and molecular refractions and from their critical co-
efficients only. The relationships for a number of hydrocarbons
are given, and the deduction is drawn that these hydrocarbons
have the same molecular weights in the gaseous state, in the
critical state, and in the liquid state. — On active amylacetic acid
and some of its derivatives, by Mdlle. Ida Well. The rotatory
powers of a number of these derivatives are given. Methyl
amylacetate has a rotatory power [ajo = + 671 ; for the cor
responding ethyl salt [o]b = + 6-66. The products of asym-
metry calculated for the same compounds bear the ratio 375 :

96

NATURE

[November 22, 1S94

343. — On the camph .,er,es and on the constitation of camphor,
by M. A. Bchal.— Researches on the oxidation of alcohols by
Fehling's solution, by M. Fernand Gaud. Methyl, ethyl, and
propyl alcohols yield the corresponding aldehydes and salts of
the corresponding acids when the alcohol is in excess ; when
the reagent is in excess and the heating is prolonged at a higher
temperature, salts of the corresponding acids are obtained,
but no aldehyde. — Biological observations m'^&^on Schiitocerca
fercirina, Olivier, during the invasions of iSol, 1S92, and 1S93
in Algeiia, by M. T Kunckel d'Herculais.— L>n the swarming
of Termites, bv M'. J. Perez.— On the assimilation of nitrates
by plants, by M. Demoussy.

Berlin.
Physical Society, October 19.— Prof, du Bois Raymond,
President, in the chair.— The President referred to the loss the
Society had sustained by the death of von Helmholtz. — Prof
P.oemstein demonstrated an experiment of Messrs. Elster and
Geitel on the intluence of polarisation on the outflow of nega-
tive electricity which may be brought about by light. The
most suitable roelals for the experiment are sodium or potas-
sium or their alloys. A liquid alloy of potassium was charged
with negative electricity so that the leaves of an electroscope
connected with it were widely divergent. As soon as the rays
of an incandescent lamp were allowed to fall on the surface of
the alloy, the room being previously darkened, the leaves of
the electroscope approached each other as due to an outflow of
electricity. AVhen the light was polarised by a Nicol prism it
now led to a discharge only when the plane of its vibrations co-
incided with that of its incidence : in the plane at right-angles
to the above the action of the light was reduced to a minimum.

Prof. Koenig recounted the results of his researches on the

significance of visual purple. (Previously communicated to the
Physiological Society on July 20. See Natl-RE, Xo. 129S,
p. 492.) .\ discussion followed, in which the President, Prof,
von Bezold, Prof. Neesen, and Dr. Rubens took part. The
last-named supported Prof. Koenig"s view that the fovea cen-
tralis is colour-blind for blue, by pointing out that fine blue lines
in the spectnm cannot be seen by absolutely direct vision, but
only by indirect vision.

Physiological Society, October 26.— Prof, du Bois Rey-
mond, President, in the chair.— The President dwelt on the
recent deaths of their honorary President, von Helmholtz, and
Prof. Pringsheim, and drew attention to the more importatit
botanico-physiological researches of the latter. — Dr. Bendix
spoke on the influence of sterilising milk on its digestibility. |
If milk is sterilised by prolonged boiling or the passage of steam j
through it, a series of changes take place. The sugar is turned
into caramel, and the sweet taste changes correspondingly, and,
further, on cooling the fat tends to form lumps, and thus destroy
the emulsion. Three experiments had been made on children
between the ages of one and two yeais, each experiment con-
sisting of two series. In the first, the children received either
fresh milk, or such as had only been once boiled-up, together
with some white bread ; in the second, the same amounts of
sterilised milk and bread. A comparison of the nitrogen and
lat in the food and f^tccs showed that the sterilised milk was
just as completely utilised as the unsterilised, — Dr. Cowles
spoke on his cardiographic researches carried out on mammals.
In bis earlier experiments he had found the frog's heart to be
the most suitable object, lying firmly as it does in a depression
of the liver. Working with this, he had observed that as long
as the heart is normally filled with blood the apex remains at
rest on the surface of the liver during systole, whereas when
deprived of blood it is raised at each systole. -Among mammals
he had not as yet found a heart so suitable for the experiment.
In the dog, rabbit, and cat, the heart lies on the lung-tissue, is
hence easily pushed to one side, and is thus readily displaced by
any levers or other apparatus brought to bear upon it. In
monkeys, also, there is a fold of the lungs lying between the
diaphragm and the heart, so that up to the present he had not
been able to obtain any reliable cirdiographic tracings by
placing levers on t)ie outside of the mammalian heart.

GuTTINGEN.

Royal Society of Sciences. — The A\i^,:unicn June
July 1894) conums :hc following papers of scientific interest .

June 9. — ' '. Wallach : Un the relations of the carvon-series
^C„HnO) and the properties of the oximes of cyclic ketones

WO I ;oS. VOL 5 l]

(III.). J. Hermes; On the division of the circle into 65,537
equal parts. .\. von Koencn : On the geological survey of
Southern Hanover.

Tune 23.—?. I>rude : Studies on the electric resonator.

■July 7. — David Hilbert : Outlines of a theory of Galois'
Zahikcrper. K. Schering and C. Zeissig : New photographic
method of registering the time and the position of the magnets
in magnetometers and galvanometers. Ludwig .Aschoff: Cor-
tribvition to the subject of atypical epithelial proliferation and
the origin of pathological glandular growths.

BOOKS, PAMPHLETS, andSERIALS RECEIVED.

Ho)KS. — N'viclicnictnde: Prof. H. I. Haas (Leiprig, Weber).— .-^ Labora-
tory Manual of Organic Chcmi»tr>' : Dr. W. k. Umdortf (Boston, Heath).
—Practical Methods in Microscopy C. H. Clark (Boston, Heath).— Life at
the Zoo: C. J. Cornish (Seeley) — .Membit Club Reprints, No. 9 : The
Elementary Nature of Chlorine ; Humphr>- l)avy(Edinburzh. W, F. Clay).
—Outlines of Biology ; P. C. Mitchell (Methuen)— Radiant Suns: A.
Giberne (Seeley).— By Vocal Woods and Waters. E. Step (Bliss) —
Kh>thmic Heredity: H. C. Hiller (Williams and Norgate).— Report of the
Filth .Meeting of the Australasian Association, September 18.15 (Sydney). —
Practical Inorganic Chemistry ■ E. J. Cox, jrd edition (RivinjtonX—Aus-
trala-i.a. Vol. 1 : Malay-la and the P.-tcific Archipelagoes : Dr. F. H. H.
Guillemard (Stanford).— Cloudland: Rev. W. C. Ley (Stanford) —Primer
ifP-ychology : Prof. J T. La Jd (Longmans). — Psychology for Teachers:
C. Lloyd Morgan (.\moM).

Pamphlets.— Notes on Tours along the Malabar Coast : E. Thurston
(Madras)— In Defence of Pasteurism : Dr. M. B. Colah (Bombay) —
Mittcilungen des Vcrcins fur Erdkunde zu Halle a.S. 1894 (Halle a.S. ).

SKKlAt.s.— Psychological Review, November (Macmillan). — American
Meteorological Journal, November (Ginn).— Journal of the franklin Insti-
tute, November (Philadelphia). — Journal of the Anthropological Institute,
November (K. Paul).— Royal Natural Histor>-, Part 13 (vVarne).— Pro-
ceedings and Transactions of the Queensland Branch of the Royal Geo-
graphical Society of Australasia. 1S03-94 (Brisbane). — .-Vstronomy and
.\stro- Physic*, November (Wesley).— .American Naturalist, November
(Wesley) —i.c Monde des Plantes : P. Constantin, fasc. i (Paris, Bailliere).
English Illustrated Magazine, Christmas (19S Strand).

CONTENTS. PAGE

Psychology of Mental Arithmeticians and Blind-
fold Chess-players. By Francis Gallon, F.R.S. . 73
The Collected Works of Olbers. By J. L. E. D. . . 74

Quaternions 70

Our Book Shelf:—

Stephen: "Sir Victor Brooke, Sportsman and

Naturalist " 7^

Briggs and Bryan : " A Text-book of Dynamics. A

Text-book of Statics " 76

Pickworlh: ' The Slide-Rule."— W. J. L 77

Pizzetti : " I Fondamenli Matematici per laCritica dei

Kisultati Sperimcntali." — G 77

" Tcppicherzeugung im Orient " 77

Orndorff; " A Laboratory Manual " 77

Letters to the Editor:—

lingerPrints.— Sir W. J. Herschel, Bart. . ... 77
BoUzmann's Minimum Function. (Il'it/i Diagram.)

S. H. Burbury, F.R.S 78

The Kinetic Theory of Gases.— Edwd. P. Culver-
well 7S

Homogeneity of Structure the Source of Crystal

Symmetry.— H. A. Miers 79

Gravitation. — Prof. A, M, Worthington, F.R.S. . 79

The Koucault Pendulum Experiment. -G. A. R. . . 79

.■\n Observation (ill Mollis.— Dr. L. C. Jones ... 79

Photographs of a Tumbling Cat. (lliiairaUJ.) ... 80

Biology in the United States— A Prospect. By

G. B. H 81

Notes 82

Our Astronomical Column : —

Observations of the Transit of Mercury 85

Kphtmerisof lincke's Comet 85

Recent Observations of Jupiter 85

The New Cypress of Nyasaland. {Ulinlrated.) . . ..85

bchiapaielli on Mars 87

Early British Races, II. (llluslraleJ.) By Dr. J. G,

Garson 9''

University and Educational Intelligence 92

Scientific Seiials 93

Soclellc^ 4iid Acaden ies 93

Books, Pampolets, anj Serials Received 96

NA TURK

97

THURSDAY, NOVEMBER 29, 1S94.

LOCOMOTIJ'E CONSTRUCTION.
The Construction of the Modern Locomotive. liy George
Hughes. Pp. 260. (London : E. and F. N. Spon,
1S94.)

OK all the many branches of engineering, that of
locomotive engineering has been generally over-
looked by the writers of te.\t-books, and until quite
recently the only works on this important subject were
the classic. il works of Z. Colburn and D. K. Cletk,
" Locomotive Engineering and the Mechanism of Rail-
ways," and " Railway Machinery." These works are
more than twenty years old, and do not now represent
modern practice, although the rules and formula; given
are largely made use of to this day, besides which the
experimental data obtained by D. K. Clerk on the old
Edinburgh and Glasgow Railway, some time before the
year 1S55, may still be regarded as of great value.

Locomotive engineers in this country owe more to the
late Mr. William Stroudley than they care to admit. To
Mr. Stroudley is due the thoughtful and careful designing
of every part of the locomotive, from the valve motion
to the damper on the ash-pan, and, thanks to his example,
locomotive design has become as near a science as it is
possible to be, always bearing in mind that abstract cal-
culations are nearly useless for this purpose. A very
important point in the design of a locomotive is that of
facility of repairs in the running-shed. It is possible
to point to more than one type of British engine where
the draughtsman appears to have had entirely his own
way in the design, and consequently an ordinary repair,
such as changing a spring, entails the partial stripping
of the engine in order to lift it high enough to
effect this : whereas it should be possible to do it
with a couple of jacks, just to ease the weight off the
spring, take the pins out, and then replace the spring.
Another similar case may be quoted. Some heavy main
line passenger tank engines have recently been con-
structed ; and should a copper stay leak badly on the
side of the fire-box, the side tanks cannot be removed to
get at the leak without cutting out rivets and removing
the angle-iron supporting the side platform ; whereas had
the draughtsman been an engineer, he would have fore-
seen such an emergency, and provided for it. These
examples are sufficient to show that when designing an
engine, the position of every pin and bolt should be care-
fully considered, so that their removal, if necessary, will
be an easy matter in the running-shed.

The volume before us, unfortunately, does not deal with
design, but treats only with the manufacture of a locomo-
tive in the works of the Lancashire and Yorkshire Rail-
way Conip.'iny at Horwich. As these works are compara-
tively new, it is only fair to expect to find the practice
thoroughly up to date, and as the author is an assistant
in the chief mechanical engineers' department, the in-
formation given may be considered to be authentic. The
title chosen for the book is a little misleading, because
only one type of engine is discussed ; moreover, this engine
is fitted with the Joy valve gear, a type of motion cer-
tainly not generally adopted by locomotive engineers.
NO. 1309, VOL. 51]

Thework is divided into six sections,and these areagain
subdivided when necessary. Each section describes the
actual progress of the work done in that section. Taken
as a whole, this book is unique ; it is the only one we
know of that appeals to the locomotime engineer in
the language and phraseology of the works, and without
the cant usually found in text-books of to-day dealing
with mechanical subjects. The book being of a thoroughly
practical nature, it may be as well to follow its contents
in order.

Section i. deals with the boiler, the materials used in
its construction, and the methods of manufacure. Steel is
the material used for the shell in most cases. The author
observes that if a plate is buckled, this buckling is got
out of the plate by planishing, or by a multiple roller
straightening machine. The former method cannot
be recommended for boiler-plates, but for tank side, cab,
or splasher-plates it is the common practice. The ques-
tion of locomotive boiler drilling is thoroughly well gone
into, but the methods described are not those of most
recent practice, which may be concisely stated to be—
the edges of all plates must be machined, rivet and other
holes to be bored after rolling the plates to shape, and drill-
ing all holes out of the solid. Many complicated multiple
drilling machines have been constructed to meet these
requirements, but it is questionable whether such com-
plicated tools are necessary, especially when the self-
pitching attachment is used, because the holes in each
seam must be set out in order to find the position of
the holes for the "holding together" bolts, which
are usually placed 12 to 14 inches pitch, and which are
usually drilled through a template in bunches before the
plates are rolled. Further on the author describes a plate-
bending machine capable of rolling a plate to the very
edge. As such a machine is certainly very badly wanted
it may be here questioned whether the one described
is really capable of doing this. The old method of setting
the last 4 or 5 inches with a "former" has long been
condemned, but with vertical rolls the ends of the plates
may be rolled to the true radius by means of a curved
packing piece which holds the plate up to the movable
roll, resting against the smaller live rolls behind.

We are told that the inside and outside butt strips are
sheared to size, and not machined on edge ; unless they
are afterwards annealed, this practice cannot be com-
mended. One cannot help being astonished at the free
use of cast-steel in the boilers. This is very much up to
date ; but what gain there can be in using a cast-steel tee-
bar in place of a rolled one for the longitudinal and sling
stay attachments, cannot be seen. The crown of the fire-
box is stayed with cast-steel girder-stays or roof-bars,
and ferrules are used to preserve the proper distances.
Surely these ferrules might be replaced by bosses cast on
the stay-bar, into which the bolts would be screwed, thus
strengthening the bar, and being less complicated. The
foundation rings are also of cast-steel ; these castings
evidently require much setting and " paening." Surely
they are machined inside and out, as required by good
practice ?

The paragraphs dealing with flanging plates and the
tools used, leave nothing to be desired ; they are concise
and to the point. Reasons might have been given for
the adoption of the " Webb " fire-hole ; it seems to

98

NATURE

[November 29, 1894

«ntail very severe treatment of the plates for no obvious
purpose. There are many ways of placing the copper
stays in position, and the author evidently cuts off the
ends after screwing them home. Here he is behind the
times : " modern practice " requires them to be cut to
length in the lathe, afterwards being screwed home by a
sort of stud-driver. This does away with any chance of
injuring the threads by cutting them in position by
eccentric portable shears, or the more barbaric hammer
and chisel.

The quadruple tapping machine (illustrated) no doubt
does its work very well, but it must be moved from boiler
to boiler, and this entails much labour and loss of time ; a
far simpler tool is generally used, namely, a light radial jib
carrying a movable carriage, over which the ropes run to
the tool-holders, all the compensating gear being on the
wall. Taken as a whole. Section i. is extremely well
written, and covers a large field of detail ; it concludes
with the testing of the completed boiler. The hydraulic
test of 200 pounds per square inch is much below the
usual test-pressure in water, viz. one and a half times the
working pressure, for new boilers.

Section ii., occupying eighty-seven p.iges, is dis-ided
into three parts. The first part deals with the iron
foundr>-, the second on the use of steel castings, and
the third describes the brass foundry. It is evident, \
after careful perusual, that much attention has been given j
to this particular branch of the works, especially the
careful manner in which the mixings of the different
metals is carried out, and the valuable illustrative tests '
showing the necessity for annealing steel castings. As
an example of foundry practice, we find a full description
of the moulding of a pair of twin cylinders, probably the
most difficult and important piece of work occurring in a
railway foundry ; a few other examples are also given. In
part two of this section the author wisely suggests that
engineers should formulate a standard specification for
the grade of material for steel castings for locomotive
work, and recognise a standard size for both tensile and
bending test bars. With this we cordially agree ; speci-
fied tests vary far too much, and in some cases tend to
make the specifying engineer a laughing-stock for
contractors.

Section iii., dealing with forgings, is divided into two
parts. The manufacture of tyres, axles, coupling rods,
and smaller details, is well described, the usual tests
being given. The method of work is illustrative of modern
practice, particularly the stamping of detail work under
the drop hammer. Engine tyres for India usually are
required to have a minimum tenacity of from 42 to
44 tons, and with a sectional area of test piece of
\ square inch. The extension, measured over a length
of 3 inches, must not be less than 20 per cent. The
second part of this section deals with the manufacture of
springs, among other things. Page 164 illustrates the
means taken to weld a lever on to a shaft ; figures C and
F may make a "job," but it is preferable to fit the lever
end half through the shaft before welding — that is, for a
brake or a reversing shaft ; for a damper shaft, a dab weld
may be good enough.

In Section iv. we find a description of general
copper-smith's work ; and in passing we may observe that
the hemispherical tops for steam dome casings are in

NO. 1309, VOL. 51]

some works made from mild steel plates in dies under
the hydraulic press, as well as the upper parts of safety-
valve casings and corner mouldings for fire-boxes. This
reduces the cost of these items considerably.

The machine department of a locomotive works is
always interesting. The machinery is in many cases of
a special nature ; and in railway works, where duplica-
tion is said to exist, the machines may be still more of a
special type, because only one class of locomotive is
made. The Horwich Works appear to be largely fitted
with milling machinery, to judge by the amount of care
the author takes in his descriptions. Whether milling in
its competition with planing, slotting and shaping
machines, will ultimately prove the cheaper process,
remains to be seen. On page 204 we find the statement
that all frame-plates are put on the levelling table and
straightened (levelled ?) by the aid of two hydraulic jacks ;
further on we read that the frame template has been
given up, owing to its liability to become distorted, and
that a man can draw in a frame in two hours: again, it is
stated that a batch of eight frames is slotted, firstly by
roughing out, and secondly by a finishing cut. Surely
this cannot be called modern practice ? To thoroughly
and truly level a frame-plate it is necessary to heat it to
a cherry-red heat, and level it on a plain surface ; for this
reason it is usual to punch the frame-plate roughly to
shape before being levelled. This punching to shape
allows the frame-slotting machine to commence at once
roughing out the bunch of plates. Moreover, the plate is
] more or less annealed by the furnacing.

The frame template generally used is made in three
' pieces dovetailed together, and the angle-iron bracing is
conspicuous by its absence : very little trouble is caused
by such a template. Surely the author has made some
mistake in stating that a man can '• mark out one frame,
which is a two hours' job." To mark out a frame from
a drawing, without a template for slotting and drilling,
will take one man two days or more. Moreover, the
frame-plates are not said to be planed on one side.
If this is the case, much time is lost in erection and
fitting the horn-blocks, assuming of course this fitting is
properly done. Such a frame-plate can be planed in from
three to four hours.

Case-hardened wrought-iron axle-boxes are said to be
things of the past ! The Midland KaiUvay Company use
nothing else, and many new engines for other rail-
ways are being fitted with them ; in fact, such boxes
working in chilled cast-iron or cast-steel guides are hard
to beat.

The last section of this interesting book deals with the
final erection of the engine, and we are glad to see that
Horwich does not go in for throwing an engine together
in ten hours or] more, to be afterwards re-erected when
the " wonder " has ceased to be talked about.

It appears that the practice of fitting the horn-blocks
to the frames when in a vertical position is followed.
This cannot be commended ; it is far easier for the
men to do it before they reach the erecting-shop, when
laying on trestles ; the holes can then be opened out,
and the bolts or cold rivets driven in comfortably.
Pianoforte wire has long been abandoned for squaring
over cylinder centre-lines by contractors, for the
reason that it can be bent between the fingers, and

November 29, 1X04]

NA TURE

99

thrown one way or another by the men. The three-inch
tube for setting the slide-bars cannot be trusted for
accurate work, owing mainly to the end drooping by its
own weight, and slackness in the glands and temporary
front cylinder cover. .Squaring over the frames is nowdone
by a long square, one arm being placed through the driving
horns, and held against them. The distance is then
measured from the leading and trailing horns to the
other arm of the square when held in the four positions.
If the frames are square, these measurements should
agree, if the horns are similar throughout. A woven
silk cord is best for lining up the frames and cylinders.

The volume concludes with a lengthy description of
the Joy valve gear, a gear not generally used in loco-
motive work. It is a pity the author does not treat the
so-called .Stephenson link motion in a similar exhaustive
manner. In conclusion, we must congratulate the author
on having written the first readable and accurate book
on the construction of the locomotive engine. He has
treated his subject in a masterly way ; he describes, as a
rule, the most recent practice in a thoroughly professional
manner. The work is well and copiously illustrated, and
will be of great use to those who take an interest, either
professionally or in an amateur way, in the construction
of the locomotive. N. J. LoCKYER.

INDO-MALAYAN SPIDERS.
Malaysian Spiders. By Thos. and M. E. Workman.
Parts I, 2, and 3. (Belfast : Published by the Authors,
1S94.)

THE material upon which this work is based was
obtained by the authors during a recent visit to
the East Indies ; and since the entire collection has
been submitted for e.\amination and description to Dr.
Thorell, who has made a special study of the Arachnida
of this quarter of the globe, it may be taken for granted
that the species have been as satisfactorily identified as
is possible. Most of them, whether old or new, have
been already described in detail by this specialist. But
his systematic zoological work, although in its way of
unrivalled excellence, is open to two objections. We
have, in fact, heard it alleged, firstly, that the span of
human life is too short, and the number of existing
spiders too great, to admit of deserving attention being
paid to his exhaustive descriptions ; and, secondly, that a
deal of vexatious trouble and valuable time might be
saved by the addition of a few figures to the overwhelm-
ing amount of text. It is evident that Mr. and :\Irs.
Workman have realised the full force of these two objec-
tions ; for this book of theirs may be briefly described as
a supplement designed to make good the defects in Dr.
Thorell's report upon their collection.

The work is being issued at intervals in shilling parts,
of which three, comprising in all twenty-nine plates, have
up to the present time appeared. Every species is
illustrated by a hand- coloured figure, together with out-
line sketches of structural details ; and accompanying
each set of figures is an explanatory page of text, giving
the name and synonymy, the affinities and distribution
of the species, and some measurements of the type-
specimen. Moreover, in some instances interesting
items of news respecting habits, &c., are added ; and in
the case of the orb-weavers, a figure of the web charac-
NO. 1309, VOL. 51]

teristic of the species is engraved on a separate plate.
It is this part of the work, we feel sure, that w ill prove of
the greatest interest to the student of spider-life. Even
the pure systematist may learn from it valuable facts
bearing upon his aspect of the subject. For the figures
and descriptions of the webs afford indisputable evidence
that remotely allied genera may construct snares of
substantially the same kind, as may be seen by a com-
parison of the nests of Callinethis, Gea, Argyroepeira,
Epeira, and Gaslracantha, represented in parts I and 3 ;
and that within the limits of the same genus, species may
be found that spin webs differing widely in important
points of structure, as a glance at the figures of the webs
of Epeira calyptrata, iinicolor, and heccarii, in parts i
and 3, will show. Clearly the importance of these facts
must be steadily kept in view by those who base their
classification of spiders on the structure of the webs.

The discovery of the snare of Uloborus qiiadri-tuber-
culatiis has given rise to a curious problem. This web
is always spun on the pine-apple, and is of a peculiar
basket-shape, the peculiarity consisting in the remark-
able adjustment that is exhibited between the structure
of the web and that of the plant. But the pine-apple is
a native of South America, and has only of late years
been introduced into Singapore ; so that if the spider is
truly a native of the latter place, it has evidently rapidly
modified its spinning instincts in response to the slight
change in its environment brought about by the introduc-
tion of the pine-apple. Before such a conclusion, how-
ever, can be looked upon as an established fact, evidence
must be produced that the spider and the plant were not
concomitantly brought from the Neotropical to the
Oriental region.

Another very interesting fact is noticed in connection
with Argyroepeira striata. We are told that this spider,
which is normally of a bright golden tint, " has the power
j of darkening down its brilliant colouring when fright-
i ened.'' (part 3, p. 19.) The importance of this obser-
vation is greatly enhanced by the independent discovery
made by Mr. H. H. J. Bell, and published in X-\ture
(vol. xlvii. p. 558), to the effect that a West African
species of Argiope possesses the same faculty of rapidly
varying its colour under the stimulus of changing sur-
roundings.

From what has now been said, it may be judged that
the value of this book, as an addition to the literature
of spiders, is both great and unquestionable. But it is
impossible to shut one's eyes to the fact that its general
excellence is slightly marred by a few blemishes, which,
at the risk of appearing ungrateful, we think it our duty
to point out ; not, be it understood, with the object of
fault-finding, but in the hope that none of them may be
copied by other authors, and that some, at least, may
not reappear in succeeding parts of the work.

In the first place, respecting the method of publica-
tion, it is a pity that both preface and introduction have
been altogether omitted, and that species belonging to
such widely different families as Oxyopida:, Attida,
Thomisidce, and Epeiridcc, should be indiscriminately
mixed, as they have been in part i. With regard to
the preface, we hope that the authors will see the appli-
cation of the maxim, "Better late than never"; and
although the adage, " What is done cannot be undone,"

lOO

X.-i TURE

[November 29, 1894

holds good in the case of the parts already issued, we
should like, nevertheless, to see a little more method
displayed in the grouping of the species contained in
the forthcoming parts.

In the second place, since more than one species is
now for the first time made public property, it may
prove as serious an oversight as it is an irreparable one,
that the exact date of the issue of the several parts has
not been permanently recorded on the title-pages. More-
over, these new species, instead of being rendered con-
spicuous as such by the familiar symbol n. sp., are ascribed
to Dr. Thorell, with the simple addition of the words
" Thorell MS." No doubt the considerations of courtesy
expressed by this ascription are worthy of all praise ;
but it will be as well to bear in mind that the species
arc for the first time described and figured in a work,
not by Dr. Thorell, but by Mr. and Mrs. Workman. It
is, consequently, within the bounds of probability that
some of us may feel inclined to question the right of the
latter two authors thus to constitute the former the
founder of these species ; seeing that his sole claim to the
title rests upon an unpublished suggestion respecting their
names, coupled with a privately expressed opinion that
they were new forms.

We should also like to suggest that a little more pre-
cision in the printing of the figures would greatly add to
the value of the plates, without much increasing the cost
of their publication. If this and the other alterations
we have ventured to propose are adopted for the remain-
ing parts, it is certain that the work, when complete, will
rank as one of the most important contributions to the
natural history of spiders that has appeared in the last
quarter of this century. R. I. POCOCK.

THE PLATEAU REGION OF SOUTHERN
FRANCE.
The Deserts of Southern France ; an Introduction to tlie
Limestone and Chalk Plateaux of Ancient Aquitaine.
By S. Baring- Gould, M.A. With illustrations. In
two volumes. (London : Methuen and Co., 1894.)

THE region described by Mr. Baring-Gould, lies,
roughly speaking, to the south and south-west of
Auvergne, forming a kind of border-land to that country
and the Cevennes. .Most of it goes by the name of Les
Gausses. This is a limestone region, furrowed deep by
gorges, and pierced by caves. On the eastern side it
rises, in three steps, from the neighbourhood of the Gulf
of Lyons to the central iiuissif of ancient granite and
schists and of comparatively modern volcanic-rock ; on
the western side it falls, in like manner, to the sandy
lowlands on either bank of the Garonne.

The scenery of these gorges is always striking and
often grand ; the finest canons being those traversed by
the Lot and the Tarn. Mr. Baring-Gould's first men-
tion of the former river may serve as an example of the
characteristic scenery.

" Near its cradle it passes under the frowning Gausses
of Sauveterre, then it cleaves the limestone of the
Rouergne, and afterwards winds and writhes like a ser-
pent through the Gausses of '^uercy. Everywhere, at
every stage, it affords surprises ; the scenery is sublime
and quaint. On both sides the cliffs arc encrusted with

VO. 1309, VOL. 51]

castles and domestic habitations, built half into the crags.
Churches and towns stand on the tops of the cliffs, and
look down on the boats that glance by. In its sinuosities
it washes overhanging scars, without leaving soil at their
feet on which to plant a foot, whereas an alluvial meadow,
rich and rank, is on the farther bank : then, suddenly,
the capricious river turns to the opposite side and treats
it as the first. Consequently a road was only to be
carried up the Lot valley by means of tunnels and
bridges."

Among the natural wonders of this region, its caves
and swallow-holes are not the least. These Mr. Baring-
Gould seldom ventured to examine in person, but he
quotes extensively from M. E. .-\. Martel, one of their
most adventurous explorers, and gives some excellent
illustrations. The latter remind us of similar features in
the Carinthian Alps to the north of Trieste, and in the
Carboniferous Limestone districts of our own country,
with which Prof Boyd Dawkins has made us familiar in
his book on " Cave Hunting." In exploring these under-
ground regions a human interest is not always wanting ;
for the investigator may come across the skeleton of a
suicide or the remains of prehistoric man, while the
stalactites are sometimes remarkably fine.

It is unfortunate that Mr. Baring-Gould did not get
some friend, more expert in geology, to look over the
proofs of his book. His references to that subject are
often wanting in clearness and precision, and thus arc
sometimes rather perplexing. This is perceptible even
on the title-page, where he speaks of the " limestone and
chalk plateaux." But " chalk " /.f a " limestone," so we
conclude that the author uses the term in a limited sense,
whether it be the descriptive or the geological. But if
the former, then, so far as we are aware, the soft white
limestone which we call chalk does not occur in the
Cretaceous system of Southern France ; and if the latter,
some distinctive epithet, such as "Jurassic," should have
been inserted before " limestone." Such a statement as
this also is puzzling: "The lowest stage (of the Gausses)
. . . is of chalk with a layer of lias above it in places."
This is incomprehensible, unless Mr. Baring-Gould uses
chalk merely as a synonym for light-coloured limestone
(which he often does, unless we misunderstand him), or
some strange faulting has occurred (which seems highly
improbable). The following passage, also, will hardly
satisfy either a zoologist or a geologist :

" The Dolomitic limestone is held to be coral rock built
up under water by the industrious insect that is at jjresent
forming reefs and islands in the Pacific. At the time
when these tremendous masses were composed, the lias
lay at the bottom of a warm shallow sea, and on its
banks the coral worm worked. Gradually the bottom of
the sea sank, and as it sank, so did the insects build
upwards towards the light and warmth. After a lapse of

ages the whole was upheaved \s the construction

is vertical, the structure is vertical, and as the coral
insects twisted and turned about sponges, masses of sea-
weed, and avoided cold currents, the whole mass of rock
abounds in hollows in which water accumulates, and in
passages through which rivers run. '

These, however, are trilling blemishes, which can be
readily put right in a second edition. The book is de-
lightful reading, and is full of interesting information, at
which we have only time to glance. Mr. Baring-Gould,
among other things, gives a good account of the curious
fire-hills of Gransac, produced by spontaneous com-

November 29, 1894]

NA TURE

lOI

bustion, in the coal basin of Decazeville and Aubin. His
description also of the irreparable mischief wrought by
the reckless destruction of forests, is well worth reading,
for it must be remembered that the weird desolation of
the limestone plateaux is a thing of comparatively recent
date, and an indirect consequence of the French Revolu-
tion. Of the rock shelters of the " reindeer age" in the
valley of the Dordogne and of other rivers, he has much
to say, and of the dwellers in " holes of the rock " down
to the present day ; for these caves have been enlarged,
or faced with masonry, or actually excavated, at various
dates, and in some cases are still inhabited. Of the
dolmens and other megalithic remains which are com-
mon on the plateaux region, Mr. Baring-Gould writes as
one who has made a study of the subject. Perhaps some
of his ethnological speculations may not meet with uni-
versal acceptance, but they are, at any rate, worth con-
sidering. The book contains many curious bits of
folk-lore, as we might expect, and narrates sundry
remarkable historical episodes in the medix'val struggle
between France and England, and in the spnguinary
conflicts of Huguenots and Romanists. A chapter is also
devoted to the romantic, though often discreditable, story
of Jo.ichim Murat, who was born at a dirty little " bas-
tide " of the same name on the Causse de Gramat, near
the source of a tributary of the Lot. The book, in short,
while it indicates the author's cultivated tastes and wide
range of reading, directs the attention of travellers to a
region of singular and varied interest, which hitherto
has received but little notice even from the French
themselves. It is only inadequately described in
Reclus' great work, "Gdographie Universelle." It has
not, however, escaped the indefatigable emissaries
of Baedekker, who gives, in the volume on Southern
France, a succinct account of the district, evidently
founded on personal knowledge. Armed with the little
red book, and Mr. Baring-Gould's more bulky volumes, a
rich reward undoubtedly awaits the visitor. The guide-
book will direct his steps aright ; Mr. Baring-Gould's
pleasantly written and admirably illustrated volumes will
give him abundant information about the chief points of
interest, whether physical, archaeological, or historical,
and will be an unfailing resource during those hours of
enforced leisure, which, on a journey, are apt to become
tedious. T. G. Bonnev.

OUR BOOK SHELF.

An Eliinentaiy Treatise on Theoretical Mechanics.
Part 1. Kinematics. Part II. Statics. By .Mexander
Ziwet, Assistant Professor of Mathematics in the
University of Michigan. (London and New York:
Macmillan and Co., 1893.)

Amkric.an mathematicians have always followed the
system of the French and continental school, so that the
progress of the .American student in analytical develop-
ment has not been arrested and stunted by the excessive
reverence of the Newtonian methods prevalent in this
country.

According to the continental system a student is
introduced at the earliest possible stage to the Cartesian
methods of geometry and to Leibnitz s extensions in
the domain of the Differential and Integral Calculus ;
and then, even with a comparatively small equipment
of analytical knowledge, hardly extending beyond an

NO. 1309, VOL. 51]

acquaintance with the notation, he is prepared to study
and appreciate a work like the present ; while the Eng-
lish student is kept back by clumsy antiquated methods,
on the pretext of developing his geometrical and general
reasoning powers.

This work is intended as an introduction to the science
of theoretical mechanics, adapted to the particular wants
of engineering students who, with the characteristic
practical energy of their race and age, will not desire to
be kept marking time over the rudiments.

The general treatment of the subject is elegant and
complete, and valuable collections of illustrative examples
are introduced at the different stages. One of these,
however (ex. 6, § 276), caught the eye, as requiring amend-
ment ; as also the Fig. 29 of the catenary.

.•\n old friend, the problem of the beam in a bowl — in
other words, of a spoon in a teacup — given as ex. 20,
g 151, deserves separate discussion, and a complete
solution in the text.

The present opportunity is favourable for expressing to
Prof. Ziwet the thanks of mathematicians in this country
for his valuable Report of Prof. Klein's Lectures on
Mathematics, called the " Evanston Colloquium," held
before members of the Congress of Mathematics in
connection with the World's Fair at Chicago, at North
western University, Evanston, 111. G.

By Order of the Sun to Chile to see his Total Eclipse,
April 16, iSg-^. By J. J. Aubertin. Pp.152. (London:
Kegan Paul, Trench, Trubner, and Co., 1S94.)
Two years ago Mr. J. J. Aubertin, having seen a copy of
N.\TURE for October 13, 1892, containing a letter on the
then coming solar eclipse, went home and dreamed a
dream. In his vision the Sun visited him and ordered
him to gird up his loins, and go to the desert of .Atacama
and watch the eclipse. This brief explanation is necessary
in order to account for the rather clumsy title of the book
before us. Mr. Aubertin, regardless of the belief that
dreams should be reversed, and that he was seventy-five
years of age, travelled to Chile, and, meeting Prof.
Schaeberle there, became one of the eclipse party. He
was, however, more an interested layman than a scientific
observer, and therefore his book is of very little value
to astronomers. In fact, the book is chiefly taken up
with tittle-tattle of interest to very few beyond the parties
concerned. A picture of the corona, as seen by the
author, is very pretty, and compares favourably with the
impressions recorded by observers of the phenomena
before photography monopolised the field as a coronal
artist. But at the present time, the results of visual ob-
servations of the corona are regarded with suspicion, and
rightly, for they never afford any very definite information
as to the true form and structure of the sun's surround-
ings. However, Mr. Aubertin faithfully records what he
saw, so his observation must be accepted. The book
contains Prof. Schaeberle's photograph as a frontispiece.
/\eise nach Siidindien. Von Emil Schmidt. Mit 39
Abbildungen im Text. (Leipzig : Wilhelm Engelmann,
1894.)
Herr Sch.MIDT's book is a plain, straightforward narra-
tive of a tour through Southern India, in the course of
which he visited Madras, Travancore, made an excursion
to Cape Comorin, proceeded by Trivandrum to Cochin,
and thence by Coimbatore to the Anamalay Hills, going
afterwards to the Nilgiris, and finishing at Calicut. The
object of the journey was mainly to study the native
peoples, and numerous ethnological photographs give a
certain value to the book. There is, however, nothing
new in the way of an important contribution to science
in the work, which is most interesting as showing the
impressions produced on an intelligent and observant
German by a visit to Southern India. The style is lively,
but perfectly serious, and cannot fail to be of nnjch value
' in Germany, where it appears few books have been pub-

I02

NATURE

[November 29, 1S94

lished dealing with the lighter aspects of Indian life. It
is pleasant to note that Herr Schmidt found the English
otiicials and planters everywhere very hospitable and
cordial, ready to assist him in his inquiries as to the
people, and able to give him much valuable information
on the subjects which he was studying.

By Vocal Woods and Waters. Bv Edward Step. Pp. 254.

(London : Bliss, Sands, and Foster, 1S94.)
A RESURRECTIO.N book, made up of papers originally
contributed to Good Words, Leisure Hour, Sunday
Magazine, Silver Link, and other periodicals. The
author is well known as a close observer of nature, and
he has the amount of poetry in his composition essential
in a writer on popular natural history. The book is
nicely printed and illustrated.

LETTERS TO THE EDITOR.
[_Tke Editor dots not hold hirme!/ responsible for opinions ex-
tressed by his correspondents. Neither can he undertake
to return, or to correspond ivith the writers of, rejected
manuscripts intended for this or any other part cf NATURE,
No notice is taken 0/ anonymous communications, ]

Acquired Characters.

I.N reference to the question as to how far the signification
of the term "acquired characters" may usefully be extended
beyond the precise limit given in Lamarck's two laws (quoted
in my letter of November 15), or what phenomena may be
brought into close relationship with those indicated by Lamarck,
the following considerations, will, I think, be found useful.

Let us consider a relatively stable local "race" of some
species of organism. The race is found to present a certain
range of variation, but has an average character ; and cases
approximating to the average are so far more numerous than de-
partures from it, that for our immediate purpose we may leave
the aberrant individuals out of account. The average specific
character is a matter which may be determined by measurement
and weighing. It can be stated in numerical form as to length
of such and such parts, breadth and depth of other parts, weight
{i.e. amount) of pigment or other chemical product here or
there. We know by experiment that these quantities can be
altered in immature individuals -.I'ithin limits by changing the
physical conditions in which the individual is placed. These
physical conditions are (roughly speaking) such measurable
quantities as those relating to temperature, light, mechanical
strains, moisture, and varying amounts of chemical compounds
or elements operating on the organism through its absorbing
surfaces (respiratory organs, digestive organs, integument).

From such experiments we are led to conclude that without
destroying the life of an individual many characters can be in-
creased in quantity, bat that there is a limit beyond which they
cannot be so increased ; and that many characters can be re-
duced in quantity in the same way in an individual without
destroying its life, but that here also there is a limit. Hence it
seems that we are justified in distinguishing the "potential"
from the " actual " characters of an organism.

This potentiality of the individual is something inborn or con-
genital. On the other hand, ihe actual quantitative condition of
the average characters of a naturally occurring assemblage of
individuals is necessarily to some extent the result of the opera-
tion of the measurable physical agencies which constitute the
normal environment of the species or race. (The range of
difference, it may here be noted, between the potential and the
actual characters of a species .-is thus indicated, is found to differ
very greatly in different species and in regard to different parts
of the organism.) Thus then every individual exhibits certain
quantitative characters, the amounts of which are determined by
the operation on the individual of given and related quantities of
external agencies. Toacharactcr thus quantitatively determined,
some writers have extended the term "acquired character,"
inasmuch as it is not the congenital potential character in its
purity (if such a thing were possible) which we thus contemplate,
but the congenital character as moulded, increased, or restrained
by surrounding conditions. Hut whilst I am very decidedly of
opinion that a consideration of this moulding, expanding, or
restraining influence of the normal environment is likely to throw

NO. 1309, VOL. 5 l]

important light upon the implications of Lamarck's doctrine, I
agree most emphatically with Mr. Francis Gallon in thinking
that the use of the term " acquired char.icters " must be limited,
as indicated by Lamarck's own statement, to characters, " which
are regularly found in those individuals only which have been
suljjected to certain special and abnormal conditions" (to quote
Mr. Galton's words). The word "acquired " was used by
Lamarck, and should continue to be used as pointing to an
acquisition, under neiv conditions, of «<:;;■ ch.aracter or characters,
distinct from the normal characters which form, as it were,
the starting-point, however determined or brought into
existence.

It is, however, true that the difference between the actual
characters of an individual organism as compared with its
potential characters — a difference the origin of which may be
expressed by calling the former "responsive characters" — is of
the same order whether the actual characters are determined in
their amount by the normal environment of the race, or by
abnormal quantitative changes of that environment.

.\nd it seems to me, that in considering this we are led to the
conclusion that the second law of Lamarck is a contradiction of
the first. Normal conditions of environment have for many
thousands of generations moulded the individuals of a given
species of organism, and determined as each individual developed
and grew "responsive" quantities in its p.irts (characters) ; yet,
as Lamarck tells us, and as we know, there is in every indi-
vidual born a potentiality which has not been extinguished.
Change the normal conditions of the species in the case of a
young individual taken to-day from the site where for thousands
of generations its ancestors have responded in a perfectly defined
wav to the normal and defined conditions of environment ;
reduce the daily or the seasonal amount of solar r.idiation to
which the individual is exposed ; or remove the aqueous vapour
from the atmosphere ; or alter the chemical composition of the
pabulum accessible ; or force the individual to previously
unaccustomed muscular effort or to new pressures and strains ;
and (as Lamarck bids us observe), in spite of all the long-con-
tinued response to the earlier normal specific conditions, the
innate congenital potentiality shows itself The individual
under the new quantities of environing agencies, shows wirtw
responsive quantities in those parts of its structure concerned,
new or "acquired " characters.

So far so good. What Lamarck next asks us to accept, as
his "second law," seems not only to lack the support of ex-
perimental proof, but to be inconsistent with what has just
preceded it. The new character, which is e.\: hy^olhoi, as was
the old character (length, breadth, weight of a part) which it
has replaced — a response to environment, a particular moulding
or manipulation by incident f )rces of the potential congenital
quality of the race — is, according to Lamarck, all of a sudden
raised to extraordinary powers. The new or freshly-acquired
character is declared by Lamarck and his adherents to be
capable of transmission by generation ; that is to say, it alters
the potential character of the species. It is no longer a merely
responsive or reactive character, determined quantitatively by
quantitative conditions of the envlronnR-m, but becomes fixed
and incorporated in the potential of the race, so as to persist
when other quantitative external conditions are substituted for
those which originally determined it. In opposition to Lamarck,
one must urge, in the fir>t place, that this thing has never been
shown experimentally to occur ; and in the second place, there
is no ground for holding its occjrrence to be probable,
but, on the contrary, strong reasun for holding it to be
improbable. Since the old character (length, breadth,
weight) had not become fixed and congenital after many
thousands of successive generations of individuals had developed
it in response to environment, but gave place to a new character
when new conditions operated on an individual (Lamarck's first
law}, why should we suppose that the new character is likely to
become fixed after a much shorter lime of responsive existence,
or to escape the operation of the first law ' Clearly there is no
reason (so far as Lamarck's statement goes) for any such sup-
position, and the two so-called laws of Lamarck are at variance
with one another. To push the lu.alter further — in those cases
in which experiment has been made, it has been found th.at a
character acquired by an individual removed from the operation
of a related condition normal to the race of which that in-
individual is an example, is replaced by the old character when
the old condition is restored in the environment of the off-
spring of that individual. No doubt I shall be challenged to

November 29. 1894]

NATURE

10-

produce evidence confirming this last statement. I admit that
carefully studied and conclusive instances are not very numerous,
but I refer to such cases as the non-transmission [a) of plus or
minus variation in pigment produced in individuals by greater
or less exposure to sunlight ; (/') the effects of dry or moist
climate on individual plants ; [c) the effects of change of diet on
individual animals ; (</) the effects of increased use of muscles in
men and animals.

It seems that we are driven to the conclusion that the causes
which have been active in producing changes the accumulation
of which amounts to specific, generic and larger differences,
must be causes which are able to act upon the potential con-
genital quality of the individual, and that there is no reason for
associating the somewhat superficial and late responses or
reactions of the parts of a growing individual lo normal or
abnormal forces of its environment with that more subtle and
profound disturbance, which is permanent and affects the
potential character of the germ, and mote or less of all the germs
derived from it.

At any rate this is the absolutely unanimous testimony of all
those observers, in all countries and in all ages, who have been
practically concerned (often with vast pecuniary interests at
stake) in the production of relatively permanent new races of
animals and plants. Breeders of horses, cattle, sheep and
dogs, pigeon and poultiy-fanciers, crop growers, nurserymen,
tulipomaniacs, and the like, have never in any single instance
put the Lamarckian principle into practice. On th.; contrary,
they laugh it to scorn. Not one of them ever produced a new
race by moulding the parents. But, on the other hand, they do
subject (he selected parents to novel and disturbing con-
ditions, to which the changed characters of the offspring (not of
the parents) have no "responsive" relation; they cross-breed
here and cross-breed theie, until the "specific potential" is
broken-down, and strange unlooked for varieties are born and
grow up irrespective of normal or abnormal environmeni.
From these congenital variations they select desired forms, and
perpetuate them with perfect assurance and security.

For the present I see no evidence of a production of new
races on the face of the earth, excepting by the method adopted
by these men, viz. by the selection of congenital variations ;
such congenital variations being produced as the result of (but
without any direct adaptational relation to) a disturbance of
the material of the reproductive particles of both sexes ; that
disturbance being increased, if not determined, by changed
environment of the parental organisms or the coupling of remote
strains. E. PIay Lankester.

Oxford, November 17.

The Present State of Physiological Research.

The extracts given in N.a.ture of November 15, from an article
by Prof Max Verworn, of Jena, on " Modern Physiology," will
serve to draw the attention of biologists to the reawakening of
interest which is now evinced by many physiologists in regard
to the fundamental phenomena exhibited by living things. As
the opinion of physiologists is expressly invited in reference to
the questions raised in this article, I venture to express my own
as being in the main the same as that of Prof. Verworn.

It seems to me an obvious truism to say that the methods
which can ensure a real advance in general biological knowledge
must be those in which comparative physiology takes the lead.
In my recent presidental address to the Liverpool Biological
Society I urged the establishment of laboratories for the
systematic study of the comparative physiology of the simpler
organisms, the end in view not being the elucidation of the
functions of organs '«\\.\\&narrure pais^t as to their relation to
man, but the examination of the activities for their own sake,
since this inquiry forms the only means of approaching the
mystery which enshrouds the essence of living existence.

The determination of the reactions of simple organisms to
physical changes (stimuli), and the grouping of such resultant
effects carried out systematically, form a line of physiological
inquiry of transcendent importance, both because of its large
scope and fundamental character, and because it opens the way
towards the partial elucidation of the physiologist's real pro-
blem. This problem is the one involved in the question, to
what extent all living phenomena are to be regarded as reac-
tion phenomena ? Are we, on the other hand, compelled to
postulate the existence in every living thing of a ./«« ex machimi

which can, if it will, act independently of every physical
stimulus, a so-called " vital force " \

Prof. Verworn is right in forcing upon the attention of
physiologists the paramount necessity for work of this kind. I
venture, however, to point out that he has not done justice to
the judgment of his contemporary physiologists if, as I imagine,
he has been led to infer from the character of the mass of
current physiological work, that they do not realise the import-
ance of such comparative physiology. But to realise the
importance of an inquiry and to be able to carry that inquiry
into effect, are unfortunately by no means identical positions.

There are undoubted obstacles to the latter, however ardently
we may desire its fulfilment.

In the first place physiology is, in this country, more or less
shackled by its position. It owes everything to medicine. Its
laboratories are adjuncts to medical schools, its professors must
take their share in the teaching in such schools, and this teach-
ing is essentially connected with human physiology.

The debt, which as physiologists we owe to medicine, is one
which we gratefully acknowledge, but even with the thanks on
our lips we may be supremely conscious of the chains which
still hang on and impede the debtor. It is this close relation-
ship which, in my opinion, has served to accentuate the separa-
tion between physiology and the science of which it properly
forms part, biology ; a separation which is now almost a
judicial one, and if unchecked may become an actual divorce.
It is rare to fine a physiologist who has been highly trained in
zoological investigation, and rarer still to find a zoologist who
has attempted to perfect himself in the methods used in physio-
logical laboratories. Vet the appropriate blend is essential for
the advent of those comparative physiologists who alone can
do full justice to the systematic inquiry now advocated.

Another difficulty in this country is undoubtedly due to the
scanty pecuniary help afforded to scientific work which is
neither technical nor directly concerned with what is regarded
as the public good. Physiology, to-day, is maintained in Great
Britain solely because it forms an essential part of a specialised
technical education, that of the medical student ; it is not
maintained in order to inquire into the mystery of living things
as such

In order to adequately develop such an inquiry as this, it
would be necessary to have a new department furnished with
the equipment of both a zoological and a physiological labora-
tory, and with skilled workers who have leisure to prosecute
their investigations. Since this means money, its full establish-
ment may have to be postponed until that pious benefactor
appears whose dawn even a Bodleian librarian has now anxiously
to await.

Finally, I do not think the outlook is so discouraging as Prof.
Verworn seems to believe, nor that " we are making no progress
in physiology."

He admits that during the last twenty years we have attained
to a precision in our experimental methods such as excites the
astonishment of the uninitiated ; and surely the mastery of
method is the first step, and that an invaluable one, towards its
future more fruitful employment. I do not imagine that even
the systematic physiological investigation which he advocates,
will involve the employment of new methods to the exclusion
of old ones ; it is the material which will be novel, not the
entire experimental technique. Isolated instances of the
application to simple excitable organism^, of .such physiological
methods as have been employed in ekaborate detail for the inves-
tigation of muscle, nerve, &c. , are well known to us all, and to
no one better than Prof. Verworn ; the real desideratum is^
surely that the instances should be no longer isolated, but form
part of a broad systematic inquiry. FrAiN'CIS Gotch.

University College, Liverpool,
November 17.

Wilde's Theory of the Secular Variation of Terrestrial
Magnetism.

Mr. Wilde's reply in Nature of October 11 to my letter
of criticism in the same of August 9, with respect to his com-
munication to the Royal Society, contained in the Proceeditigi
for .March 1S94, has just come to my attention.

As the letter consists entirely in an attempt to show
the inaccuracy and unreliability of my statements with re-
spect to the inclination-observations made at St. Helena,

NO. 1309, VOL. 51]

104

NATURE

[November 29, 1894

behoves me to confine my own remarks to this matter. In
order that my explanations may be understood, the table
previously given is here reproduced.

No.

Dale.

Observer.

^ Observed
inclinitioa.

Wilde's
incHnation.

Observation
-Theory.

-rf!

I

1700

Kansteen Chan

2° S.

3°9N.

1 B

1 -59

2

17543

La Caille

9-00

0-5 S.

' -8-5

3

'77«-4

Ekeberg

i3'00

3-5

, -95

4

'775-4

Cook

1 1 42

40

-74

5

1780

Hansteen Chart

10-5

51

-54

0

18250

Duperrev

14-93

14-7

-0-2

7

1S401

Ross

iS-27

18-5

> +0-2

S

'S42-3

Belcher

1 7 00

190

+ 2-0

9

18468

Smyth

1939

20-5

1 +11

10

1890-1

U.S.C. &G.S

29-65

33-8

t ■<-4-l

II

18901

•■

31-18 S.

33-8

; +2-6

This table is in every respect the same as originally given
with the exception of the v.alue for 1700, the erroneous value of
1 1' 5 S. having been given instead of 2' S. Owing to my sojourn
in Europe being but a temporary one, I have not with me all
my data, and so cannot ascertain definitely how this error crept
into my table. My original scaling was probably 15 S., which
by a copying blunder may have been converted into 1 1 -5.
This, however, I cannot control now. It would have been a
most natural inference on Mr. Wilde's part if he had ascribed
'.his to the " printer's devil," all the more so as no use what-
ever was made in the text of my communication with this
value. On account of so apparent an error he casts a slur upon
my trustworthiness in general in regard to terrestrial magnetic
matters. Such a poor method of argument reveals the weak-
ness of his position.

Furthermore, with reference to this table, Mr. Wilde says :
" I regret to observe that L. h. Bauer, in his intolerance of the
magnetarium results, has inserted in his table guesses of his own
for observations, which are very wide of the truth." I can
find no excuse whatever for this statement. Mr. Wilde has
acknowledged that he possesses a copy of Hansteen's " Mag-
netisms der Erde." Let him turn to Tafel II. : " Neigung der
Magnetnadel," p. 36, and he will find the following observa-
tions given for St. Helena : —

Obacrver.

Dale. 1 Inclination.

DelaCaille . .

Ekeberg. . . .
Cook . . . .

April 10, 1754 90S.
May 19, 1771 13 0 S.
May 17, 1775 " 25 S.

Position assigned by Hansteen: latitude 15° 55' S., longi-
tude II' 52' E. of Ferro, or 354' 12' E. of Greenwich. By in-
specting the table given above it will be seen that these form
Observations Nos. 2, 3, and 4. Xo. 5, as slated, is taken from
Hansteen's Chart for 1780. Mr. Wilde does not appear to
question this value, nor the remaining ones, which can be
easily found in Sabine's " Contributions to Terrestrial Mag-
netism." He will, furthermore, find thai Hansteen had so much
faith in the early observations, which Mr. Wilde insinuates
are unirustworlhy, that in 1857 he made use of all the observa-
tions known up to that time, viz. Nos. 2, 3, 4, 6, 7, 8, and 9,
for the establishment of a periodic formula representing the
secular variation of the inclination during this epoch. These
investigations of Hansteen's can be found in " Den magnctiske
Inclinations Korandringcr i den nordlige og sydlige Halvkugle
af Christopher Hansteen," Copenhagen, 1857, -4'. Hanslccn,
by a least square adjustment of the observations named, derived
the following interpolation formula : —

1= - i3'58-455 - 5'-44405(/- iSoo) -o''ooioi3 (/- 1800)'.

I denotes the inclination at the time /, south inclination
being reckoned as minus. This formula at the utmost should
not be used more than ten years prior to 1754, nor ten years
later than 1S46. The following table shows how the values
computed with this formula agree with observation.

NO. 1309. VOL. 51]

Date.

1754-28
1771-58
'775'38
1 824 96
1S4010

' 842-35
1846-79

Observed
incUnaiion.

From this comparison it will be seen that the formula re-
presents the observations fairly well. Let us compute then
with it what the inclination would be in 1747. We obtain
- 9°'2. Now Mr. Wilde's magnetarium has given us for this date
ihe value 00. Hence there is an oulstanding difierence of
about 9', which he has made no attempt to explain other-
wise than by insinuating that I have put "guesses" in my
table, or that the observations are unirustworlhy. The burden of
the proof that the observations are not trustworthy, rests with Mr.
Wilde. Anyone, who has made any endeavour to familiarise
himself with the literature of the subject of terrestrial mag-
netism, will know that it is an old story for theorists to charac-
terise observations as doubtful if they do not happen to agree
with their theory. I am willing to admit that the early inclina-
tions in such a locally disturbed region as St. Helena, perhaps,
cannot be depended upon nearer than to 2' or 3° ; but, if
Mr. Wilde will pardon my scepticism, 1 do not believe that
it is possible for him to reproduce .\ny inclination with his
magnetarium that can be relied upon even to this extent.
Hence, it is fair for me to compare the magnetarium results
with that of observations (so long as the latter have not been
overthrown) without consideration of the probable error of
either result.

Mr. Wilde appears to have thought his position proven
when he found that I made an error wilh respect to my first
value. But even wiih the value as given by him, the outstand-
ing difference is 5°-6°, with which he. appears perfectly
satisfied. If he will permit me a probable error as large as he
permits himself in the establishment of his theory wilh his
magnetarium, I can supply him with a dozen periods that will
satisfy observations as well as his magnetarium. I would like
to refer him to a recent attempt by Dr. F'clgentraeger, who
endeavours to prove the universality of the secular period by
establishing periodic formuire upon the b.asis of most carefully
collected material. He deduces a period of 477 years — instead of
Mr. Wilde's 960— upon the basis of the declination observations
made at London 15S0-18S2, and Paris 1541-1890.' Adopting
this period he found that he could represent exceedingly well
the observations made at London, Paris, Rome, Clausthal,
Chambersburg (U.S.A.), Rio de Janeiro, Cape of (lood Hope,
and Cape Comorin. Here we have a more extensive comparison
than .Mr. Wilde has given us, and we find a better agreement
with observations with a period one-half of his! In this brief
communication I cannot set forth my o«n position with respect
to the secular-variation period. I hope to present Mr. Wilde
with a copy of my investigations some time in December.

With respect to my opinion of the magnetarium in particular,
I may say that my criticisms m.ide thus far have applied solely
to the theory as evolved from the magnetarium results, and do
not touch the magnetarium as a valuable instrument of research.
Indeed, I think much good can be accomplished with it. Mr.
Wilde has m.ade a most laudable attempt to reproduce mechani-
cally the complex phenomena of terrestrial magnetism, and if
the achievements with his ingenious mechanism had not received
Ihe publicity they did, or had been propeilv iiilerpreted, my
criticisms would never have been made. That he has not
succeeded in giving us a better representation is no fault of
his, but owing to the complexity of Ihe phenomena.

The fact that Mr. Wilde has succeeded, by an arbitrary dis-
tribution of magnetic mailer in his m.agnetaiium, in representing
the Jistriliulion of terrestrial m.agnetism for Ihe year 1880
apparently so well, is no proof of his secular-variation theory or
his period, which plays no part in determining the distribution.
Nor is the fact that wilh hii distribution of magnetic matter he
gets a good representation a proof that that is the actual distri-

' Dr. W, K<:'KenIr.ieger : Die lungtle nachwciobarc Siiciil.irc Pcrinde der
erdm.-i(ineliichen Elenienie. 'Icil i: Deklinalion. Iiiailg. Diss. Universiut
zu li'-ltingcn, G"ttingen, \%i, Buchdru-.Ic'rci vnn Lou-s Hofer.

November 29, 1894]

NATURE

ic;

bution prevailing in the uarth. It can be demonstrated as a
mathematical fact that in the absence of terrestrial magnetic
observations wilhin and without the earth's surface, an infinite
number of different distributions is possible that will satisfy the
effects observed on the surface alone.

In conclusion, it is my duty to make one more explanation.
Mr. Wilde understood from my first letter that I am .still in the
employ of the U.S. Coast and Geodetic .Survey. In view of
the fact stated by him, that he sent, at considerable trouble and
expense to himself, a duplicate of his magnetarium to the
" Survey," and, hence, it might appear that it was somewhat
discourteous in a member of the " Survey " to thus criticise him
publicly, I may say that I severed my connection with the
Survey two years ago, and that my criticisms have been made
without any knowledge whatsoever of what has been accom-
plished with it by the " .Survey."

Friedenau bei Berlin, October 31. L. A. B.\uer.

Boltzmann's Minimum Theorem.

Mr. Culverwell's letter of October 25 ought lo have re-
ceived a much earlier answer. That it did not do so was owing
to purely accidental circumstances which I very much regret.

In that letter Mr. Culverwell criticises my treatment of Boltz-
mann's familiar proposition concerning the properties of the H
function on the following grounds : —

(i) The choice of the generalised coordinates. In investi-
gating the circumstances of a collision or an encounter between
two systems of molecules of m and it degrees of freedom re-
spectively, he sees a difficulty in my choice of the coordinates
as Qi, Q2 . . . Q,,„ y,, q-i . . ijn, where (y„ = a) deter-
mines a collision, or encounter. But supposing the requisite
number of degrees of freedom to be secured, the choice of the
independent variables is surely quite optional. I had myself
assumed this as self-evident, perhaps too hastily, but at any
rate Mr. G. H. Bryan has placed this proposition beyond doubt,
in the exhaustive report submitted by him to the British
Association last August. Take for example sets of plane
circular disks moving amongst each other in their own plane ;
here each pair of disks constitutes a material system, whose
position is completely determmed (assuming the orientation of
each separate disk to be indifferent) by the following four vari-
ables, viz. the two coordinates of the centre of one disk of the
pair, the distance p between their centres, and the inclination
of that distance to a line fixed in the plane ; this third variable
f is the ./„ of my proposition.

(2) Mr. Culverwell objects that the general Boltzmann proposi-
tion j , always negative unless F/= Fy j, or H a minimum

for one, and one distribution only, cannot be true, because if a
system were started from any initial configuration (P, Q), and
after the time /arrived at the configuration (/, (/)andthe definite
integral H were evaluated in these two configurations, the pro-
position asserts that the second H must be less than the first
H, or W, <H„, whence it would, follow by the same proposi-
tion that if at the end of the time / each velocity component
were reversed, the H^, must be less than 11/, and this, doubt-
less, I do assert. But Mr. Culverwell maintains that such an
.assertion is obviously untrue because at the end of the second
interval / the system has returned to its original condition, and
therefore W^i must be the same as H , and lo this proposition
I demur.

Doubtless when a material system in a field of any conserva-
tive forces is started from any initial position and velocities,
arrives after a time / at another position and with other veloci-
ties, and here has each velocity reversed, it is true that at the
end of the next interval / it will be in its initial position, with
each velocity component reversed ; but it remains to be proved,
and cannot be asserted </ priori, that the Hj/ is equal to H,,,
and the only proposition available for the investigation is this
very proposition of Boltzmann's, which proves that H^ will be
less than II., and therefore less than H .

Finally, Mr. Culverwell inquires, somewhat despondently, if
anyone will point out the use of the H function, and what i-^
proved by it.

I have already said in my second edition, that the proposi-
tion is not of my invention, and therefore that I have no
claim to answer this question with any authority, but to my
own mind the proposition appears certainly lo clear away one

NO. 1309, VOL. 51]

obvious difficulty. Without the aid of this proposition we are
enabled to assert that if F (p, q) were a function of the cg
ordinates and momenta of a molecule such that in the absence
of encounters -vith other moleciiks, F remains constant for all
time, then the form of F satisfying the condition F/= Y'f
must render F {p, q) ap dq a permanent law of distribution,
and therefore i( we can assert that F (/, (/) must of necesity be
of the form F (E) (E sum of potential and kinetic energy),
then the e'''^ law of distribution is certainly a permanent law
(neglecting, i.e., all but binary encounters) ; but in the absence
of this proposition, we cannot assert that the F/'= F'/' is
necessary as well as sufficient, because we cannot insist upon the
necessity of an exact compensation in the passage from the p ./
to the /' (/' state, and conversely, t.aking place at eacii upurate
encounter. The H proposition, therefore, removes this element
of uncertainty, and reduces the question to that of the F (E)
restriction, because it proves that unless F/'= F'/' for eai/i
pair of encountering molecules, H and therefore F and / must
be a function of the time. As I have already asked for a dis-
proportionate share of your space, I will not enter upon the
question of the F (E) restriction now.

H. W. Watson.

I DID not exactly, as Mr. Burbury suggests, question Boltz-
mann's minimum theorem, but only the pages thereon in Dr.
Watson's " Kinetic Theory of Gases. " Indeed, I said that though
I had not seen Boltzmann's proof, I supposed it to be all
right.

It appears from Mr. Burbury's letter that in order to prove
the theorem, even for the simple case of perfectly hard and
elastic spheres, some amount of assumption as to an average
state having been already attained must first be made, and of
course the .7 priori reasoning in my letter is not applicable to
such a theorem. Mr. Burbury's letter is exactly the kind of letter
I hoped to elicit, and if he can say what assumption in a general-
ised system will r-'place the assumption of equal distribution of
velocities in different direction in a system of hard spheres, he
will clear up the whole difficulty. Unfortunately, the case with
which he deals is one in which the error-law is known from other
considerations to be the only permanent state.

I observe that Mr. Bryan, in his British Association Report,
quotes the oversight I pointed out in Dr. Watson's proof, with-
out making any criticism on it.

Edwd. p. Culverwell.

Trinity College, Dublin, November 24.

The Alleged Absoluteness of Motions of Rotation.

Prof. Gree.nhill, in his review of Mach's "Science of
Mechanics" (Nature, November 15), writes as if he dis-
approved of that author's not accepting "Newton's distinction
between the relativity of motion of translation and the
absoluteness of motion of rotation." He appears to think that
Mach would have obtained more insight into this distinction
from a study of Maxwell's "Matter and Motion." It might
more truly be said that Maxwell would have profited by a
perusal of Mach's book The latter finally refutes the paradox
contained in Newton's statement, and supported by .Maxwell,
and by so doing renders a great service to Mechanical Science.
He has disposed once and for all of "absolute rotation. " It is
high time that writers on Mechanics should revise the prelimin-
aries of their science so as to state their results in terms of
relative motion, whether of translation or rotation. This has
been partially done by Maxwell, and a further step has now
been taken by Mach. It is unfortunate that the reviewer in
drawing attention to this part of the book should have preferred
to stand by the prejudice he owes to Newton and Maxwell when
he might have done something to hasten its abandonment.

\. E. H. Love.

St. John's College, Cambridge, November 20.

Mach s,ays truly (p. 237) "that precisely the apparently
simplest mechanical principles are of a very complicated
ch.aracter ; that these principles are founded on uncompleted
experiences, which can never be fully completed," &c.

The modern student of theoretical mechinics is in a dilemma;

io6

NATURE

[November 29, 1894

either he mast accept the complete idea of the relativity of all
molioD, of rotation as well as of translation, as professed by
Milton, Mach, and Mr. I.ove ; or else he must follow N'ewton,
Maxwell, and the German writers Streintz and Lange (attacked
by Mach in Appendix iv. ), and distinguish between the relativity
of the motion of translation and the absoluteness of rotation.
Euler, it appears, was a waverer, and according to Lange never
arrived at any settled and intelligible opinion upon the subject.
The first theory appears more analogically complete, but in-
troduces unnecessary complication at an early stage ; and
stronger arguments than those of Mach, and others that I have
yet met with, will be required to convert me to their side of the

question.

November 26.

A. G. Greenhii.l.

Science Teaching in Schools.

In the discussion on the teaching of science, and in the
schemes put forward for reorganising this teaching, mathematics
has so far been Itft out of consideration.

At present mathematics is taught for itsowneducalional value,
which has been traditional since the time of Plato ; only in
modern times has its great practical value been recognised.
The teaching in schools takes little account, however, of
the applications of mathematics, and whatever Prof. Green-
hill may say (in his review of Prof. Mach 's excellent book), there
is still wanting complete harmony between those two points of
view ; not perhaps in the higher branches of the subject and its
applications, but certainly in school teaching.

Boys, and girls too, in public schools are taught the elemenis
of mathematics as if all were expected to become mathema-
ticians, and the practical side is kept out of view. In the
modern, or science side, which has been introduced at many
schools, one finds too often chiefly those boys who show no
talent either for classics or mathematics. Many of these have
made little or no progress in Euclid ; they cannot grasp the
altogether abstract notions and symbols of algebra, and they
therefore never come near trigonometry. But they are expected
to understand the elements of chemistry, mechanics and
physics ; and it is instructive to find that they very often do
understand a good deal of what is taught under these heading-:.
Now none of these subjects can be accurately taught — and
Inaccurate leaching is worse than waste of time— without
the introduction of mathematical reasoning. Here we are
in a vicious circle : the boys are considered incapable of learn-
ing mathematics, and therefore mechanics and physics have to
be taught without any more than the most elementary notions
of geometry and algebra ; hence not much progress can be
made.

In my opinion the order of procedure might be reversed
Mathematics might be taught through experimental science. If
the boys themselves make, as they should do, experiments
where they perform actual measurements, they will learn there
are certain laws connecting various quantities ; they will see
that such laws can be exprosed in simple symbols, and they
will thus grasp in the concrete form the meaning of a formula
or an equation which in the abstract form of pure mathematics
remained a mystery to them.

Mathematics could in this manner be made very much easier
and more interesting to the majority of boys. Geometry can be
treated to a very great extent experimentally by aid of geo-
metrical drawing and a development of the Kindergarten
methods ; the abstract logic of Euclid can then follow, or it
can be treated at the same time.

Trigonometry need not be at once as fully gone into as is
generally done, but the definitions of sine, cosine, &c. , as
Dames for certain ratios, can be easily and early introduced and
made use of at or.ce in mechanics or physics. Here also special
experiments may easily be devised where measurements of
angles or lines are made, and lines and angles calculated.

To explain fully what I mean I should reiiuire a great deal
of space ; in (act it would be almost necessary to draw up a
distinct syllabuj for a course on the above lines, or to give at
least a great number of examples.

At prcient I wish only to urge that, while many attempts are

being made to improve science teaching, and with it technical

education, mathematics should be included, and to express my

opinion that this science also allows of experimental treatment.

November 19. O. IIENRICI.

NO. 1309. VOL. 51]

Mr. Crump i^:ide p. 56) though adopting a critical form and
tone, really endorses the grounds of my suggestion that the Science
and Art Department should dissever itself by an age limit from
school science. He is inclined to be especially severe upon the de-
fects of the Government examinations because they are controlled
by scientific men, and to excuse the proper school examining
boards because they have — according to Mr. Crump^attempted
to examine in science without any qualification to do so. Hut I
fail to see why eminent scientific men should be expected to be
experts in elementary science teaching, any more than distin-
guished litterateur.', in the art of teaching to read, and it seems
to me — in spite of Mr. Crump's "absolute" denial — that
examining boards, neither professedly literary nor scientific but
professedly educational, are more to blame in following and
abetting the Department's premium upon text-book cramming.
The fact remains that the London Matriculate ignores practical
teaching of any kind, and that the "practical chemistry" of
the Locals and College of Preceptors is essentially the same test-
tube analysis as the South Kensington examination. .-Vnyone
who knows the London Matriculation examination — witness
Miss Heath's concluding remark — will appreciate the quiet
humour of Mr. Crump's allusion to it as "awakening and de-
veloping the powers of observation and reasoning."

II." G. Wells.

The Explosion of a Mixture of Acetylene and Oxygen.

With reference to your note in last week's Nature, I may
say that, whilst the thanks of chemists, and particularly of those
whose duty it is to perform lecture-experiments, are due to
Prof. Lothar Meyer for once more drawing attention to the
dangerously explosive nature of mixtures of acetylene and
oxygen, it may be assumed that the facts already known con-
cerning acetjlene account sufficiently well for the great violence
of the explosion, and hence for the circumstance that the
mixture will shatter even the open cylinder in which it is
detonated. What .M. Berthelot terms the molecular rapidity
of the reaction, as distinguished from the rapidity of propaga-
tion, in the case of mixtures of acetylene and oxygen is very
high. The heat of the reaction, too, is nearly five times
as much as in the cases of electrolytic gas and of carbonic oxide,
and more than twice as much as that of methane. It is slightly
exceeded by that of ethylene, but, on the other hand, the
theoretical temperature of ihe change with acetylene is
enormously greater than in the case of any other explosive
mixture of gases. The temperature, too, required to initiate
the change is, as Prof. Lothar Meyer showed indirectly some
ten years ago, much lower in the case of acetylene than in that
ol the other gaseous mixtures of which he speaks. All the
conditions tend to make the duration of the reaction so nearly
instantaneous that the initial pressure cannot be far removed
from the theoretical pressure, and this is sufficient to smash a
much stronger envelope than a glass cylinder, even if the
" tamping " be nothing more ihan the air. Everything we
know about acetylene combines to show that it is extremely
"sensitive" as an explosive, and th.at in this respect, as in its-
destructive action, it resembles mercuric fulminate.

T. E. Thorpe.

"Newth's Inorganic Chemistry."

Thf.RE are one or two points in Mr. Pattison Muir's review,
upon which I should like to be allowed to say a few words.
Criticising the general plan of the book he says :
" It seems to me that the method of the author is radically
wrong. Descriptive statements of facts ought surely, neither to
precede, nor to follow, but to accompany the reasoning oi»
these facts whereby general principles are gained."

It is not easy to see how the Jescriptivt slalevinits of/acts, ana
\^e reasoning on these fa,:ts a.ra\.o hi: printed in a book at all,
unless one either precedes or follows the other. I can only
suppose that my reviewer means, that such theoretical and
other considerations as I have included in part i., and have
' called "introductory outlines," should in his opinion not be
I collected together cither at Ihe beginning or at the end of the
book, but should be sprinkled among the descrip'ive chapters.
It seems to me that the plan I have .i.lopied, beMdcs being a

November 29, 1894]

NA TURE

107

more orderly arrangement, and one more convenient for refer-
ence, is also the one that best enables the student to study the
subject in the way advocated by my reviewer ; and in order lo
impress upon the student that the study of descriptive facts
should accompany the study of the reasoning on these facts, he
is directed to "slowly and carefully " read part \. while he is
studying the descriptive chapters. I venture to think also, that
this method tends far less to " perpetuate the vicious and unreal
distinction between chemistry and chemical philosophy ' than
that of obliging the student to gain his information ol facts from
one book, and his knowledge of theory from another.

Commenting upon the fact that part ii. is devoted to the study
of four typical elements, Mr. Muir says :

" But hydrogen, oxygen, nitrogen, and carbon are not
treated as typical elements ; they are not compared and con-
trasted with other elements."

This criticism is not true. Chapter ii. of part iii. is prefaced
with a short general account of the elements oxygen, sulphur,
selenium, tellurium, in which the typical element oxygen is
compared and contrasted with its conjrires. Chapter iii. is
prefaced with a similar brief sketch of the elements nitrogen,
phosphorus, arsenic, antimony, bismuth, wherein the typical
element nitrogen is compared and contrasted with the others of
the group ; and similarly at the beginning of chapter ix. the
typical element carbon is compared and contrasted with silicon,
i;ermanium, tin and lead.

My reviewer is good enough to say : " The descriptions in this
ook of the members of each group of elements seem co me to
e exceedingly well done ; many portions of the chapters treat-
i\l; of principles and theories . . . are admirable." And again,

few lines further on : " The purely descriptive portions of the

ijrk are often extremely good, as far as they go. The facts,
r rather half-facts, are stated in a clear and orderly way."

I am a little curious to know what half-facts are ; and
whether if such things can be, it would be possible to state them
" in a clear and orderly way." If my reviewer merely means
that there are so many more facts known than I have stated,
hat roughly speaking it may be said that I have only described
ne half of the known facts, I can only reply that I have
'endeavoured to select *' from the overwhelming burden of so-
called facts " such as seemed to me to be most important for the
student, and which could be conveniently included within the
limits of a small text-book.

Mr. Muir finds fault with my book because he does not dis-
cover in it "some fair and fitly fashioned building," which he
says "ought to rise on this broad superstructure " I regret
that this objection has not been stated in rather more explicit
terms ; I have ttied to understand it, but cannot — perhaps it is
poetical. In ordinary language one does not speak of a build-
ing as rising upon a superstructure. In no text-book of chemistry
with which 1 am acquainted, is any trace of such a phantom
edifice to be found, and it is sincerely lo be hoped, that when
the Joshua appears, who by raising such a "fitly fashioned
building" shall "rescue chemistry from the overwhelming
burden of so-called facts beneath which the science is in danger
of being buried," he will choose some more suitable vehicle for
making his views known to the scientific world than that of an
elementary text-book on inorganic chemistry.

G. S. Newxh.

I STILL hold that Mr. Newth's method is radically wrong.
I admit it is not easy to make the descriptive statements of
chemical facts accompany the reasoning on these facts ; but
although not easy it can be done.

As regards Mr. Newth's treatment of the four typical
elements, hydrogen, oxygen, nitrogen, and carbon, I can only
repeat that the comparisons and contrasts made between these
elements and those of which they are representative are, in my
opinion, worth very little.

I cannot enter into a discussion of the meaning of the term
"half-fact" ; but I can assure Mr. Newththatin saying he had
staled "half-facts in a clear and orderly way," I did not mean
to say he had stated about half of the known facts and omitted
the rest. It is characteristic of hall-facts that they are very
amenable to clear aud orderly arrangement.

When I spoke of " some fair and fitly fashioned building "
rising "on this broad superstructure," of course I should have
written "broad substructure." I am much obliged to Mr.
Newth for pointing out this stupid slip.

NO 1309, VOt. S']

I thought Joshua was more concerned with demolishing towns
than with raising buildings ; but my Hebrew history is a
little rusty. M. M. Pattiso.n Muir.

Cambridge, Nov. 21.

Singing Water-Pipes.

At Oxford, Prof. Osborne Reynolds showed an interesting
case of sound in water. There is another familiar effect, of
which he has probably given the reason, but it does not seem
to be commonly known.

A little while back there was a clear steady note carried
through my house by the water-pipes, a note of the middle
octave of the quality of an organ diapason pipe. When the
source was found, it was easy to change the note through the
octave. The music arose as often as the scullery tap was
turned on, and lasted so long as the water was running. The
tap was worn, and the flow of water kept up a rapid tapping of
the loose part, just as in Trevelyan's Rocker.

The singing is sometimes heard after a tap is turned off.
This happens because the ball-tap of a cistern has thus been left
running. W. B. Croft.

W'inchester College, November 26.

An Aurora on November 23.

Steppi.n'g out of doors to-night, November 23, at 7.30, 1 was
surprised to see the whole northern sky filled with luminous
mist, so clear that our shadows were dimly observed on the
shining surface of the wet highway. There were few tremulous
motions, but the light clouds advanced southwards in great
patches. For a while the planet Jupiter shone to the east of the
luminous haze. Then the mist passed over Jupiter, who shone,
however, with nearly its wonted splendour until a great de-
tached belt hung between Jupiter and Pleiades, over to the
south-west horizon.

The Milky Way became obscured as the haze passed right over
our heads. By eight o'clock the detached luminous belt, which
was not uniform, but in patches, had reached the planet Mars.
Neither was the light in the north uniform, but here and there
were clear spaces. By 8. 10 the aurora was much dimmer. By
8.30 there was no luminosity except in the north, between the
Great Bear and the horizon. J. Shaw.

Tynron, Dumfriesshire.

A Snake "Playing 'Possum."

A ruFFi.NG adder, Heterodon platyrhintis, caught by the
writer in May 1894, exhibited a most curious instance of feigned
death which may be worthy of record.

The snake when discovered at first tried to escape, but on
being captured it turned on itself with mouth wide open, head
thrown back sharply, and tongue limp and protruding. The
mouth remained open thus to its fullest extent, while the head
and upper part of the body threshed violently from side to side
for a few times, and then his snakeship rolled over on his back,
and after a few convulsive movements became apparently lifeless.
The body was then quite limp, and remained in whatever posi-
tion it was placed, providing the snake was on his back, but
when turned over in the proper position, he immediately rolled
back by an almost imperceptible muscular contraction. When
struck lightly, pinched or held up by the tail, there was very
slight resistance. He continued in this state for about half an
hour, when no attention having been paid to him, he resumed
his normal position. A little leasing caused a repetition of this
performance a number of times afterwards, and it did not vary
in any essential particular. It would be interesting to know
whether this is a ruse common 10 individuals of this species, and
if so whether it is confined to them alone.

L. C. Jones.

The Soaking of Seeds.

In reply to Mr. Alfred W. Bennett's inquiry as to the
soaking of seeds in milk before sowing, it may interest him to
learn that in book iii. section v. of his "Deipnosophists," Theo-
phrastus is quoted by .-Mhen.-eus as saying that "cucumbers
contain a more agreeable and wholesome juice if the seed be
steeped in milk or mead before it is sown," and that "plants
come up quicker if they are steeped in water or milk before
they are put in the ground." P. C. Glubb.

Pendean, Liskeard, November 13.

io8

NATURE

[November 29, 1894

HISTORY OF E SOKE'S COMET.

HISTORICALLY, Encke's comet, which has recently
come into view again, stands next in interest to
Halley's. The history of the latter can be carried back
much farther than that of any other comet. It was in-
deed conjectured that the one (the first telescopically
discovered comet, by Kiich) which made so near an
approach to the sun in i6So, and in reference to which
Newton first applied his principle of universal gravita-
tion to the motions of these bodies, was identical with
comets seen at intervals of about 575 years before, and
Gibbon (not exactly an astronomical authority, who
recommends others to study Newton and Halley on the
question) devotes a section of his forty-third chapter to
the supposed history of these early appearances (two of
them in mythical times', concluding with the remark
that the calculations with regard to it might perhaps
in the year 2355 "be verified by the astronomers of
some future capital in the Siberian or American wilder-
ness,"little thinking how many splendid telescopes would
be employed on the study of the heavens in the " far
west," before a century had elapsed from his own death.
There was then, in 1794, no observatory on any part
of the American continent. But it is now known that
the period of the comet of 16S0 amounts not only to
hundreds, but to thousands of years ; and one of the
supposed previous appearances, that in the reign of the
Emperor Justinian, was in all probability a return of the
smaller or less conspicuous comet which appeared in
l6S2,and at the next return in 1758-9 acquired the name
of Halley's comet, because that eminent astronomer had
confidently predicted its return at that date, calling upon
posterity to notice that the prediction had been made by
an Englishman. He recognised its identity with comets
observed in 1531 and 1607, by a comparison of the orbits
calculated for each, and considered from the similarity of
period, that the fine comet of 1456 was also probably
an earlier appearance of the same. Later investigations,
and the accessibility of Chinese records, have shown
since his time that successive appearances of this body
can be traced with very great probability to a date before
the Christian era, our distinguished countryman, Dr.
Hind, having taken a leading part in these calculations.
Of the subsequent observations of this comet in 1S35,
this is not the place to speak, nor of the full expectation
astronomers then living will entertain of seeing it again
in 1910, and applying the new methods of analysis to it,
thereby obtaining information respecting its consti-
tion, which was beyond the wildest flights of imagination
at its last appearance. Tor our present subject is a comet
which acquired the name by which it is now universally
known as a fitting meed of honour to an astronomer who
worthily presided over the then new observatory at
Berlin within our own recollection. .Many comets have
since that time returned according to prediction ; but
when Encke announced that the small one discovered by
Pons at .Marseilles on November 26, 1818, was identical
with the discovery of Mcchain in 1786, of Miss Herschel
in 1795, ■''"d °f Thulis in 1S05, no predicted return of !
any comet but Halley's had ever taken place, though two
predictions had been made, by himself and by Bessel re-
spectively, of the returns of comets observed in 18 12 and \
1815, which duly came to pass in 1S83 and 1887, the
periods of these being nearly as long as that of Halley's.
The remarkable point about Encke's comet was the ex-
treme shortness of its period, amounting only to 1212
days, or three years and about four months. It was
therefore concluded that it would reappear in 1822 ; true
to prediction it did then appear, but from its situation in
the heavens was visible only in the southern hemisphere,
which then possessed only one observatory, that estab-
lished (but which has long ceased to exist) by Sir Thomas
Brisbane at Paramatta, New South Wales, wherj the

NO. 1309, VOL. 51]

comet was rediscovered by Riimker on June 2. The
next appearance took place in the autumn of 1825, when
the comet was observed in this hemisphere, and since
that time it has never failed to be observed at the calcu-
lated epochs. Encke did not desert it after he had deter-
mined its period in 1S19, but. following up its motions
with accuracy, was led to notice a remarkable continuous
shortening of the period by a fraction of a day at each
return. The question had before his time been started
whether a medium might be diffused through the solar
system which, though insufficient to atTect the motions
of the planets, would produce appreciable effects upon
those of comets, composed as they must be of matter in a
state of great rarity. Here was a case which seemed to
settle the question in the affirmative. Encke's calculations
showing that the diminution in the observed length of the
period was such as might well be caused by the action
of such a resisting medium checking the onward motion
of the comet, which would bring it a little nearer to the
sun at each return, and thus shorten both the orbit of
revolution and the period of time in which it was accom-
plished. The difficulty remained how to explain the fact
that no such effect was perceptible in the motions of any
other comet ; a difficulty which the lapse of time has not
removed, for though in one other case (that of a comet
known as Winnecke's) a similar effect was for a while
thought to be noticed, further investigation showed that
this view could not be sustained. Encke, however, to
the end of his life (he died in 1S65) was able to trace the
above continuous effect in the motion of his own comet,
the period of which was then i2io"2 days, or i'6 days
shorter than it had been in 1S19. But, strangely enough,
soon afterwards, the amount of retardation was reduced
by about one half, at which it has remained from 1868
to the present time. Must the resisting-medium theory
be modified, or must it be altogether abandoned and
some other cause be sought for the retardation in
question.' Prof. Young suggests a regularly-recurring
encounter with a cloud of meteoric matter.

When nearest the sun, Encke's comet is at very nearly
the same distance from him as the planet Mercury.
When farthest from him, it is in the zone of small planets
(nearly four hundred of which are now known), revolving
between the orbits of Mars and Jupiter. May the at-
traction of some of these have something to do with the
effect above referred to .' Small as is the mass of most
of the tiny bodies in question, it is possible that at cer-
tain times some of them may act together and produce a
cumulative and appreciable effect. Of great value to
astronomy has been the position of Encke's comet at the
other extremity of its orbit, in perihelion. Before its dis-
covery, the mass of Mercury had been rather a matter of
conjectural inference than of actual calculation, that planet
having no satellite the motionsof which would beaffected
by its attraction. But at certain returns, the comet of
which we are treating, made very near approaches to the
planet, and the effects pro luced on these occasions have
enabled astronomers to obtain determinations of the
mass of the planet as accurate, or nearly so, as those
determined for the larger planets which have satellites.
The first of these near approaches since the comet's dis-
covery took place in 1S35 ; the last at the most recent
return, in 1891.

We now come to the physical appearance of
Encke's comet. It has on some occasions, when nearest
the i:arlh,been just visible to the naked eye, particularly
in the autumns of 1S28 and 184S. After Miss Herschel
had detected it (supposed to be a new comet), at its
return in 1795, her brother. Sir William Herschel,
observed it on November K, and noticed it the following
day pass centrally over a star of the twelfth magnitude
without obscuring it, whence he concluded that the
comet " is evidently nothing but what maybe called a
collection of vapours." Maskelyne, who observed it at

November 29, 1894]

NATURE

109

Greenwich a few nights afterwards (Bode had in the
meantime, in company with an amateur astronomical
friend, detected it at Berlin on November ii, four days
after Miss Herschel's discovery at Slough), contested
this view on the ground that the nucleus might be
situated not in the apparent centre of the comet. And
this indeed would seem to be the case ; the general
appearance of the comet, when seen under the most
favourable circumstances, being that of a slightly oval
vaporous mass, with a small ill-defined nucleus
eccentrically situated within the coma. In 1848,
towards the end of September, a faint brush of light was
noticed by Prof. Bode, extending from the more con-
densed part of this towards the sun ; and a few weeks
afterwards a tail, between one and two degrees in length,
was seen on the other side, i.e. the normal position of a
comet's tail. Late in the month of November in the
same year, it may be remarked, the comet made one of
its very near approaches to Mercury, coming within the
distance 003S of the Earth's mean distance from the
sun, or about three and a half millions of miles. The
return of 1871 was a noteworthy one in several respects ;
and particularly for the remarkable fan-like appearance
which the coma presented in November and December.

The apparent contraction of a comet's bulk as it ap-
proaches the sun, and dilatation of it again when receding
from him, which has been manifested in several of these
bodies, has been especially marked in the case of
Kncke's, the visible diameter at perihelion being not
ecjual to the twentieth part of what it is about the time
when the comet first comes into view. The most probable
cause of this would seem to be that suggested by Sir
John Herschel, which would make it rather apparent
than real, namely, that near the sun a part of the cometary
matter becomes invisible by evaporation, just as a cloud
of fog might be.

In 1871 the spectrum of this comet was examined by
Prof Young, and found to consist of three bright bands,
of which the central one was the most prominent ; they
were somewhat sharply defined on the least refrangible
side, whilst on the other they were diffused. " Of a
continuous spectrum there was no trace, and the spec-
trum was the same from every part of the comet.' But
in 1S81 a faint continuous spectrum was detected by Prof
Tacchini, so that the result of spectrum analysis applied
to this comet would seem to be essentially the same as
that obtained from the great majority of comets of which
the light has been examined in this way.

At the last appearance of Encke's comet, in 1891, it
was first seen by Prof. Barnard at the Lick Observatory
in California, at the beginning of August, and passed its
perihelion on October iS. At the present return it was
detected at the Nice Observatory on October 31, in the
constellation Pegasus ; and Dr. Max Wolf found it
registered on a photographic plate taken by him the same
evening at Heidelberg. As on several previous occasions,
its ephemeris has been calculated by Dr. Backlund, of
Pulkowa ; and it is matter of regret to notice his ac-
companying announcement that this is the last occasion
on which he will be able to undertake it. The earlier
portion of this ephemeris was given in NatL'RE last
week.

W. T. LvxN.

PROGRESS OF THE CATARACT CONSTRUC-
TION COMPANY'S WORKS AT NIAGARA.

'pHE general scheme of the Niagara Falls Power Com-
■"■ pany has already been described in these columns
(N.ATURE, vol. xlix. p. 482). We understand that the
great power house is now complete, and the foundations
ready for the three great 5000-horse power dynamos

NO. 1309, VOL. 51I

which have been constructed by the Westinghouse
Company. The turbines and vertical shafts up to the
floor of the power house have long been in place, and the
dynamos may now be shipped any day. They have
already been revolved in the shops at full speed. Our
readers will remember that there is no gearing. The
dynamos are on a vertical shaft, and the revolving fields
are external to the armature, forming a sort of bell-cover
to it, with the poles pointing radially inwards. This was
the only design which Prof Forbes could make to fulfil
the requirements of the turbine designers as to maximum
weight and minimum fly-wheel effect to be allowed. It
gives a splendid mechanical construction, as the re-
volving pole-pieces and coils are retained in place against
the centrifugal forces by the nickel-steel ring which forms
the yoke.

The first place to be supplied with current is the
aluminium works of the Pittsburg Reduction Company.
To convert the two-phase, 2000 volt alternating current
into a continuous current of 160 volts at these works.
2500 feet from the power house, transformers are there
used, and the low pressure alternating current in two
phases is supplied to commutating machmes. This is a
new departure of great interest, as no machines of this
class have been previously built except for experimental
purposes. They are each of 500-horse power, and are
continuous current machines with four rings attached to
four bars of the commutator. The alternating current is
supplied by brushes rubbing on these rings, and it drives
the machine as a motor. The continuous current is taken
from the commutator by brushes in the ordinary way.
All this machinery was made for the Cataract Con-
struction Company by the General Electric Company,
which is far the largest electrical concern in the United
States. The machinery was tried in September, and it
seems to work admirably. Four of these machines, with
eight transformers, equal to 2000-horse power, are being
put down to begin with.

The next place to be supplied is the Carborundum
Company, which makes a substitute for emery, much
harder, being composed of carbon and silicon raised to a
high temperature in an electric furnace. They begin with
looo-horse power, and their factory is making good pro-
gress.

After that the Buffalo transmission will go on, but the
selling of power in the neighbourhood is more profitable
than at a distance ; and many of the manufacturers, who
have been holding back for two years to see how the
tariff was to be settled, will now start factories, and
some of them will settle at Niagara Falls to get the
cheap power.

The transformer house, for raising the electric pres-
sure from 2000 to 10,000 or 20,000 volts, is on the side of
the canal opposite the power house, and these are con-
nected by a massive stone bridge, with a covered way
for carrying the cables. The concrete subway starts from
the transformer house, and is at present to be used for
supplying the flrst customers on the Company's lands.

Everything looks most promising at present, and
as to the electrical works, everything indicates that
any other general scheme than the one adopted
would have been vastly inferior. Especially is low
frequency proving itself invaluable. The continuous
current could not have been got for the aluminium works
without it, the motors will be far more satisfactory, and
the safety and economy of the line is far higher. It
was once objected that transformers could not be cheap
or efficient at the low frequency proposed. Prof. Forbes
held, however, that large sizes could be got even with
low frequency at half the cost and at higher efficiency
than anything that had been done on a small scale.
This statement was based upon his own designs ; and
now it is entirely supported by all the manufacturers
who have made designs for the work.

no

NATURE

[November 29, 1894

THE NILE RESERVOIR.

AN official memorandum upon the proposed modifica-
tions in the Assuan dam project has been drawn
up by Mr. \V. E. Garstin, C.M.G., Under-Secretary of
State in the Egyptian Ministry of Public Works, and is
published in Tuesday's Tiims. It will be remembered
that an account of the schemes for the irrigation of
Egypt was given in these columns a few months ago
(vol. I. p. So).

Several arguments have been brought against the
Assuan cataract as the site for the dam. The first is
that this site is not the only possible one to be found
north of Wadi Haifa. The second, and, at first sight,
the strongest, argument against the proposal is that it is
impossible to lay down as an axiom that the Assuan
cataract site is the only feasible one for a dam, while the
river valley south of Wadi Haifa has been une.'cplored and
unsur\-eyed.

Mr. Garstin criticises the arguments, and shows that
the project proposed best meets the case. In this
opinion he is supported by the English and Italian
members of the Technical Commission — Sir Benjamin
Baker and Signor Torricelli — who reported that there is
only one safe site for a dam between Cairo and Wady
Haifa, namely, the Assuan cataract. Subjoined is Mr.
Garstin's description of the scheme. The careful con-
sideration which has been given to the matter reflects
great credit upon the Egyptian Government. Science is
to be congratulated upon the action that has been
taken ; for the benefits that will accrue to it from the
investigations which it is proposed to carry out over the
whole of Nubia will be of the highest importance.

The Council of Ministers on June 3, 1S94, approved in
principle of the proiiosed dam and reservoir at the Assuan
cataract, and directed the Ministry of Finance, when preparing
the Budget for 1S95, to occupy itself with the question of ob-
taining the funds necessary for the execution of this work.

The project, as then submitted to the Government, consisted
of a dam with its crest at K.L. II4'00, which height would
have enabled wa er to be stored in sufficient quantity for the
requircmenls of Middle and Lower Egypt ; in other words, for
the whole country lying to the north of Assyut.

Most unfortunately the construction of this dam would have
necessitated the submersion for some six months every year of
the celebrated Philx temples, as well as of a considerable num-
ber of Nubian monuments, which, although less known than
those of Phila:, arc of great importance to all those interested
in the history of ancient Egypt.

The archruologlcal societies of Europe, upon hearing of this
proposal, protested against it in the strongest terms, and begged
the Egyptian Government to reconsider its decision, and to
endeavour to find some alternative scheme by which the country
might reap the advantages to be derived from a storage reser-
voir, without sacrificing the interests of science and archeo-
logy.

The Ministry of Public Works, recognising that these jiro-
tests were founded upon reasons so strong as to command re-
spect, reconsidered the whole matter in detail, and endeavoured
to find such modifications of the original scheme as might re-
concile the interests of Egypt and of science.

The result of its studies is the modified project which has now

been submitted to the Egyptian Government.

• • • ♦ •

The modified scheme as at present submitted is of the nature
of a compromise ; it is hoped that it will satisfy the scientific
world, while, at the same lime, it will further the interests of
thii country.

It is now proposed to build a dam at Assuan with its crest at
R.L. 10600, or eight melrei (26ft.) lower than that of the
original project. This work will of necessity store very much
less water than the high-level dam would have done. At the
same time a reservoir of this height will supply sufficient water
for the wants of either Middle or Lower Egypt separately,
although not for their combined areas.

This will mean that the reclamation of the country will pro-
ceed more slowly than was at first proposed ; and when in
course of time the cmniry 10 the south has been explored a

NO. 1309. VOL. 51]

second dam can be made which will store sufficient water for
the needs of the rest of Egypt.

This proposal is no new one, but has been fully discussed and
estimated for in Mr. Willcocks's report upon the different sites.
The great advantage to be derived from carrying out the work
in the above manner is that it will only submerge portions of
the Phila: island, while it will leave the rest of the Nubian
monuments untouched. A reference to Mr. Somers Clarke's
note upon these latter will show that their levels are all well
above that of the highest water surface in the modified project
as now submitted.

As regards the PhilK temples, the main buildings will be
above high-water level altogether. It is true that the South
Quay wall, and .^ome of the smaller temples, would be sub-
merged if left unprotected. It will, however, be possible, by
the construction of a low water-tight wall, or by other means,
to so arrange for their protection that no damage will be done to
them by the water.

To a certain extent the artistic beauty of the group will be
impaired, but in a land so full of interesting relics as is Egypt,
it is unfortunately impossible to carry out any great public work
without in some degree interfering with some one or other of
these. The only thing to be done is to try and minimise this
interference as far as is possible, and in the present case the
Ministry of Public Works thinks that it has succeeded in so
doing.

As regards the details of the protection works to be carried
out upon the Phila; island this Ministry will consult the scientific
societies upon every point, and will endeavour, as far as lies in
its power, to meet their wishes in the matter.

In order to still further minimise any possible loss to science
which might ensue from the construction of the reservoir, it is
proposed to carry out an archa-ological and scientific investiga-
tion of the whole of Nubia.

The English societies very rightly impressed the necessity of
this work upon the Egyptian Government. The latter, although
both willing and anxious to carry it out, found it impossible to
do so, owing to the necessary funds not being available. If,
however, the reservoir be made this difficulty at once disappears,
as the cost of the above investigation will be added to the
estimate of the dam itself

The Public Works Department has been directed to put in
hand as much of the work as lies within its scope and power
during the ensuing winter season. Topographical surveys will
be made and plans prei)ared ; the true bearings of the temples
will be fixed and the preliminary plans of all sites completed.

This portion of the work being done, the Egyptian Govern-
ment will ask the European scientific societies to depute certain
of their members to come to Egypt and complete the work.

In thi-^ manner it is hoped that a record and a knowledge will
be obtained of this most interesting country which will be
worthy of the present age, and which should be of the greatest
value to the scientific world in the future.

NOTES.

Where the good of science is concerned, the Goldsmiths'
Company is generally among the leading benefactors. With
characteristic generosity, the Company has decided to make
a grant of one thousand pounds for the purpose of prosecuting
research work in connection with the anti-toxin treatment of
diphtheria, and in aid of the manufacture of the serum. At
the request of the Company, the Laboratories' Committee of
the Royal College of Physicians and Surgeons have undertaken
the administration of the grant.

Reuter's correspondent at Rome reports that at a quarter
past six on the morning of Tuesday, November 27, an eiirth-
quakc occurred at Brescia, in Lombardy. The shock was fol-
lowed by subterranean rumblings. A simiLir, though less
violent, movement was felt at Bologna at nine minutes past six.
Kivc minutes earlier a sharp disturbance occurred at Vienna,
lasting four seconds. It was followed almost immediately by a
second slighter shock of two seconds' duration. Shocks were
experienced about the same time at nomodossola, Mantua,
Pavia, Paimo, and liergnnio, «hileat Rome the seismic instru-
ments gave evidence of disturbance.

November 29, 1894J

NA TURE

I II

The Socictc Internationale des Electricians established a
central laboratory at Paris about seven years ago. The prin-
cipal object of the laboratory was the preservation of electrical
standards, and to afford practical electricians an opportunity for
testing their various instruments. It is evident that such a
laboratory offers special advantages for the investigation of
questions belonging to the science and industry of electricity.
These facilities have been to some extent utilised ; but in order
to increase the usefulness of the institution, the Society has
added to it a School of Applied Electricity. This school, which
will be opened on December 3, has been constructed on a plot
of land granted by the city of Paris, the funds for the building
having been raised by private subscription. Purely practical
instruction will be given at the school. There will be two
chief courses, one dealing with the industrial applications of
electricity, and the other with electrometry. It is hoped that
the school will be a training ground for higher work in the
Central Laboratory, to which it is attached.

A Russian ethnographic exhibition will be held next year in
the Champ de Mars, Paris.

The University of Chicago is establishing a special depart-
ment of botany, with Prof. J. M. Coulter at its head.

It is announced that the printing of the important and
laborious " Index Kewensis " will probably be completed about
Midsummer 1895.

The death has recently occurred of Dr. L. Schwarz, the
Director of Dorpat Observatory, and the Professor of Astro-
nomy in the University there.

The resolutions passed by Convocation at Oxford, last
summer, in favour of conferring degrees upon persons who have
pursued a course of special study or research in the University,
were submitted to a Congregation on Tuesday, and, after some
discussion, the preamble was carried by a majority of sixty-nine
votes.

A Dalziel telegram from Halifax, Nova Scotia,dated Novem-
ber 27, says : "It is reported that the steamer Falcon, of the
Peary Arctic Exploration Expedition, was wrecked on the
Virgin rocks, some distance off the southern coast of Greenland
in October, and that all on board perished."

The Royal Botanical Society of Belgium has established a
Committee of Vegetable Pathology, holding its sittings in the
Botanic Garden at Brussels, for the purpose of affording informa-
tion to nurserymen, horticulturists, and arboriculturists, respect-
ing the diseases which attack plants, and the best mode of
combating them.

In January last, attention was drawn to the fact that a sale
of seven lions had taken place at the gardens of the Royal
Zoological Society of Ireland, of which number six were born
in Ireland. A further batch of five cubs, all males, has recently
been disposed of by the Council, after a protracted correspon-
dence. The total exchange value for these twelve lions ex-
ceeds, we understand, ^500.

Agricultural Associations seem to be waking up to the
necessity for the scientific investigation of diseases and pests
affecting crops. One of the resolutions passed at a largely-
attended conference of agricultural societies of New Zealand
held during the past summer, was — " That the seivices of a first-
class entomologist be obtained by Government, who shall give
his whole lime to an examination of insect pests, with a view to
their destruction." It was also resolved to request the Govern-
ment to get expert opinions as to the best method of
exterminating the grub in corn and grass crops.

The promotion of an intellectual observance of Sunday is the
object of the .Sunday Society. At present the Society numbers

NO. 1309, VOL. 51]

among its chief aims the opening of the Natural History
Museum and the South Kensington Museum on Sundays, so
that the scientific collections of the nation shall enlighten a
wider public. In furtherance of the general principle involved,
a number of special sermons will be delivered next Sunday, this
being the Society's third annual Museum Sunday ; and several
science and art collections will be open to members of the
Society.

Near Dankeld Cathedral, in the Duke of Athole's grounds,
are two of the original five larch trees said to be the first intro-
duced into this country. They were planted in 1738, and io
the year 18S8 they were measured with the following results :

Height

. 102 ft.

4 in.

Circumference :

3 ft. from ground

.. 17 ft.

2 in.

5 ft- „ ..

.. IS ft.

I in.

17 ft. ,,

.. 12 ft.

io4 in.

51 ft

8 ft.

8 in.

6Sft. „

6 ft.

I in.

Mr. Walter B. Harris gave an account of his recent
journey to Tafilet, at the last meeting of the Royal Geographical
Society. He left Morocco city on November i, 1893, in dis-
guise, and crossed the Atlas at an elevation of a little over 8000
feet. In connection with this, it is worth noting that the
Bulletin of the Paris Geographical Society (vol. xv. p. 199)
contains a description, by M. Gabriel Delbrel, of a visit he paid
to Tafilet last year.

Dr. Karl K.\rstens, of Kiel, has made a critical revision
of the various estimates of the average depth of the oceans, as
arrived at by the methods of different calculators. These
methods he classes as of three kinds : that of measuring areas by
the planimeter on a contoured map, that of calculating the
areas of successive profiles drawn at intervals of 5' of latitude
apart, and that of taking the mean depth of the soundings in
definite small areas, and combining these to give the mean
depth of the whole. Murray and Penck had made calculations
by variations of the first method, and got out the mean depth of
the oceans as 3797 metres (2074 fathoms) and 3650 metres (1995
fathoms) respectively ; Heiderich, by the second method, got
343S metres (1881 fathoms); and Kriimniel, by the third method,
gave the figure 3320 metres (1815 fathoms). Since Kriimmel's
calculations were made in i886, his student Karstens has gone
over them, taking advantage of the very numerous additional
soundings which have been made, and he comes to the con-
clusion that the average depth of the oceans as a whole is
3496 metres, or 1909 fathoms. The maximum probable value
was 3632, and the minimum 3377 metres. The mean depth of
the Pacific Ocean is given as 3829, of the Indian Ocean 3593,
and of the .\tlantic 3160 metres.

Herr P. DiNSE published the first part of a discussion of
the geographical characteristics of fjords in a recent number of
the Zeitschrift of the Berlin Geographical Society (vol. xxix.
p. 189). This instalment deals with the morphology of fjord-
riven coasts, a subsequent paper being intended to treat of the
theory of the origin of fjords, The author distinguishes
between fjords or inlets running into steep coasts, and some-
times branching, including one or more basins deeper than the
sea immediately outside, and fjord-chaniHls or sounds which
are similar but open at both ends, and fjord-lakes which are
similar but closed at both ends, and separated from the sea.
.\ farther distinction is drawn between the different kinds
of inlet which superficially resemble fjords, the most contrasted
! in submarine configuration being the rias of Spain and other
coasts, in which the depth of the water gradually increases from
the head until it merges in the general deepening of the sea
outside. The inlets of the soulh-west of Ireland areexamples
of this type, contiasting with the characteristic fjor.is of ll'.e

1 1:

NATURE

[November 29, 1S94

north-west of Ireland, the west of Scotland, and Norway. The
greater part of the paper is occupied by an account of the
distribution of the varieties of fjord-coasts in different
parts of the world, and the generalisation is made that
there are none of those coast- features outside the limits
of lands which bear signs of recent glaciation. Herr
Dinse has made a complete discussion of the principal
dimensions and the exact configuration of eighty-three fjords in
all pans of the world, taking his data from the largest-scale
sea-charts available for each region, and these figures are
printed as an appendix. The paper is illustrated by a few
contoured maps of fjords, and by profiles showing their longi-
tudinal and transverse sections.

The Gradient-Telemeter Level, of which we give an illus-
tration, should be of service to civil engineers and surveyors.
Its novelty consists in the absence of a vertical circle, while a
circle tilted out of the horizontal plane takes the place of the
horizontal circle in an ordinary theodolite. So constructed, the
instrument can be used to obtain linear distances, gradients, and
differences in level of objects without the use of land-chain or
tape. The circle is divided into natural tangents instead of
degrees. When the reading is zero, the telescope is horizontal,
but by rotating the circle, the telescope is • inclined to the
horizontal line, and the inclination is indicated by the pointer
to the circle. .\s an examp'e of the use of the instrument,

suppose the whole of the levelling staff to be below the hori-
zontal line of sight. Setting the circle for a gradient of one in
twenty-five, let the rcadirg of the staff be 13S6. Now set the
circle so that the index points to a gradient of one in twenty,
and let the reading be 8'45. The difference between these two
readings is 5'4I, and, eliminating the decimal point, the number
obtained — 541 — is the horizontal distance in feet between the
instrument and the staff, without any further calculation. Other
pain of gradients may be used, and the difference of their staff-
readings gives the linear horizontal distance. The instrument
thus greatly aimplifies many surveying operations.

A COLLECTION of valuable notes on the aborigines of various
parts of Australia is given in the November Journal o[ the
Anthropological Institute. The notes, which take the form of
answers to questions on the manners, custom^, religions, super-
stitions, &c.,of the native tribes of Australia, have been col-
lected by iJr. E. C. Stirling. The natives arc divided into
NO. 1309. VOL. 5 l]

innumerable tribes, and different customs prevail every two
hundred miles or so. Arithmetic is beyond their comprehension.
Most of the tribes appear to h.ive distinctive names for one and
two, but for three they say two and one ; for four, they say two
and two ; and for five, two two and one. The fingers are
used in counting, but numbers beyond five are very seldom
used. Numbers greater than len are usually described as
" plenty " and " many," and explained by opening and closing
the hands several times. The tribes have a very limited know-
ledge of the measurement of time. They tell the time of day
by the sun, and speak of the diiTerent limes of the position of
the sun. They reckon by so many moons, and determine the
year by the seasons ; but they have no knowledge of the con-
stellations, nor have they any names for the months, or moons,
as they call them, or any recognised beginning of the year, nor
artificial timekeeper of the nature of sun-dials, though the lengths
of the shadows of trees is used by some tribes to determine the
time of day. The heavenly bodies are not worshipped, neither
are any ceremonies performed at the new moon, sunrise, sunset,
the solstices, equinoxes, S;c. The Milky Way is supposed to
be the largest creek or river. A fresh sun is believed to shine
every day, and the phases of the moon are explained by the
prevailing course of the wind and prevailing quarter of the rain.
Eclipses, rain, thunder, lightning, rainbows, wind, and Aurora
Australis are supposed to be the work of evil spirits. Many
other beliefs are described in the notes, which will be read with
great interest by every student of anthropology and folk-lore.

The mutual alterations effected between an invading igneous
m.iss and the rock which it invades, have long been the subject
of much study and speculation. -•Vn interesting case, present-
ing some exceptional features, has recently been described by
Prof. Cole (Trans. Roy. Dublin Soc. vol. v. (n.s.) No. 5).
On the coast of Co. Down, the Ordovician strata are cut by
numerous basic dykes. In some cases, material of more acid
composition has intruded at a later da'e, and, forcing its way
along the same lines of weakness as the earlier basic material,
has produced " compound " dykes. It is one such compound
dyke, at Glasdrumman, consisting of basaltic andesitc rifted
lengthwise by later eurite, that Prof. Cole describes in detail.
The new-comer has rc-melled the more easily fusible andesite,
and the two magmas have mixed along the contact. Various
stages of mixture are described, but the most interesting facts
are those concerning the large crystals of quartz and felspar
which abound in the marginal portions of the eurite. These
crystals have evidently consolidated under other, and earlier,
conditions than the main mass of the rock, since portions of
the curite-matrix have eaten their way into them before solidi-
fying. But crystals undoubtedly so corroded are also found in
the andesite, into which they must have floated from the eurite.
The presence in a rock of crystals of evident foreign origin is
no new thing, but hitherto it has, in all such cases, been either
shown or assumed that they were caught up by the rock in
which they are found from some other into which it had
intruded ; whereas, here, it is the invading eurite that has
parted with its crystals for the benefit of its host. Thus the
common dictum, that "an enclosed block must be older than
the rock immediately enclosing il," is apparently controverted ;
yet, since consolidation is the datum from which age is
measured, it becomes a decidedly nice point in geological
nomenclature whether a partially re-fused rock can be allowed
to pass as entirely older than the rock which has re-melted it.

Some interesting particulars concerning " aventurine glass,"
one of the most curious products of the world-renowned glass-
works at .Murano, near Venice, are given in the current number
of the --/«;(■»■;■> u« /ournal cj Hcicn.t, by Mr. Henry S. Washing-
ton. Its name is derived from its supposed discovery " by

November 29, 1894]

NATURE

1 1

chance," some brass filings having been dropped accidentally
into a pot of molten glass. Afcer the late Dr. Silviati's revival
of the glass industry at Murano it was rediscovered, but the
present process is a trade secret. The best ^lass is of a copper-
brown colour, and transparent to translucent in thin flakes,
showing on the edges a pale brown colour. It is filled with
innumerable small flakes and spangles of a slightly brownish
yellow colour and brilliant metallic lustre, consisting of
crystallised copper. Under the microscope the glass shows a
porphyritic structure, the ground-mass being composed of a
perfectly clear and colourless glass basis. The crystallised
portions consist of large phenocryst.«, small phenocrysts, and
..icrolites. The former range in diameter from 0"05 to 0'I2
mm., are tubular and extremely thin, the thickness scarcely ex-
ceeding o '002 mm., and are perfectly opaque notwithstanding
their excessive tenuity. Most of them are hexagonal in outline,
the he.xagons being of almost ideal symmetry; but equilateral
triangles, which occasionally show truncated angles, also occur.
The smaller phenocrysts are much more diverse in crystalline
form, and may be generally grouped in one of three divisions :
cubo-oclahedral forms, octahedra, and twins. They occur in
portions of the glass free from the larger phenocrysts, but filled
with abundant microlites, from which they are usually
separated by a clear zone. The copper has evidently crystal-
lised out from solution in the molten glass exactly like a salt
from water, following Lehmann's laws of crystal growth in
solutions. Mr. Washington is of the opinion that the glass is
produced by melting together glass, cuprous oxide, and some
reducing agent, such as siderite ; and that FeO is in this case the
reducing agent is shown by the greenish colour of the imperfect
glass, which is not the blue green of copper, but the yellow green
of ferrous glass, and perhaps due to too large a quantity of
reducing agent.

.\T the last meeting of the French Physical Society, MM.
Cailletet and Colardeau read a very interesting paper on the
condensation of the gases produced by electrolysis on electrodes
formed of metals of the platinum group. It is well known
that when acidulated water is electrolysed by means of platinum
electrodes that, on removing the battery and connecting the
electrodes, a current is obtained in the opposite direction to the
original current used to perform the electrolysis. This current,
which only last -i for a short time, is explained by the recombin-
ation of the hydrogen and oxygen which coat the platinum elec-
trodes. The authors, taking advantage of the well-known
property of finely-divided platinum of occluding gas in large
quantity, were led to use masses of finely-divided platinum con-
tained in silk bags as electrodes, and in this way, using electrodes
weighing six grms. each, a current was obtained, after discon-
necting the battery, which continued for some time, and was of
sufficient strength to ring an electric bell. By enclosing this
'form of the cell in a receiver, and compressing the air within the
receiver, the following results were obtained : — With an
additional pressure of one atmosphere, the E.M.F. immediately
after charging was i '8 volts, which fell regularly to zero when
the cell was discharged. On increasing the pressure the
•character of the disch.irge-curve obtained entirely alters, and
consists of three parts, (i) A portion in which the intensity
of the discharge current rapidly diminishes. (2) A portion dur-
ing which the current remains constant. This period occupies
the major part of the time occupied in the discharge, and the
E.M.F. at this time is about one volt. (3) A second period in
which the current diminishes and finally becomes zero. The
capacity of such an accumulator, the weight of the two elec-
'rodes being I kilogram, is, unier a pressure of 580 atmo-
spheres, 56 ampere-hours, while a current of loo amperes can
be obtained. To obtain the best possible result, 'he negati' «
NO. 1309, VOL. 51]

electrode should contain three times the weight of platinum in
the positive electrode. With finely-divided palladium a storage
capacity of 176 ampere-hours per kilogram of palladium was
obt.iined at a pressure of 600 atmospheres. It is interesting to
note that the storage capacity of an ordinary lead accumulator
is about 15 ampere-hours per kilo of metal.

Leon Guignard, in Ihe Journal de Botanique, adds another
important contribution to our knowledge of the centrospheres
of plant-nuclei, entitled " Sur I'origine des spheres directrices."
It will be remembered that this author was the first to demon-
strate the existence of these structures in vegetable cells
(Comptes-rendus, 1S91), and also, in a later paper, to describe
their behaviour during the origin of the sexual cells and the
part they take in the phenomena of fertilisation (./«>;. dis Sc,
Nat. 1S91). In these earlier works Guignard already figured
many resting nuclei with the centrospheres lying outside the
nuclear membrane, and usually in close proximity to it, while
within the nuclear membrane are to be seen one or more
nucleoli. Strasburger also observed and figured centrospheres
outside resting nuclei in Sphacelaria scoparia {Hisl. Biitrii^e,
iv. p. 52). Recently, however, G. Karsten was led to believe
from a study of the relations of the nucleoli and centrosomes in
the mother cells of the spores of Psilottim triquiriim that the
centrosomes (or minute bodies included in the centrospheres)
owe their origin to the nucleoli, and after karyokinesis are re-
included as nucleoli in the daughter nuclei. Guignard's last
paper is chiefly concerned with an examination of this point,
and he comes to the conclusion that prior to karyokinesis the
centrospheres in the cells of the sporangia of P. triquetrum
are external to the nuclear membrane, and that after karyo-
kinesis, while some of the small nucleoli which have not
disappeared during the division of the nucleus are re-included
within the nuclear membranes of the daughter nuclei, they
remain external to them.

A RECENT number of the Minnesota Botanical Studies con
tains a bibliography on the subject of the fixation of free nitro-
gen by plants, embracing over 600 titles.

The report of the fifth meeting of the .\ustralasian Associ-
ation for the Advancement of Science, held at .\delaide, in
September 1893, has just reached us from Sydney, where the
permanent office of the Association is situated.

Messrs. Rivington, Percival, and Co. have published a
third edition of " Practical Inorganic Chemistry," by Mr E. J.
Cox. The book is intended for students preparing for the
elementary practical chemistry examination of the Department
of Science and Art.

In the form of " Bulletin No. 56," Mr. P. H. Mell, the
State Botanist for Alabama, records the result of a series of
observations on the crossing of different varieties of the cotton-
plant at the Agricultural Experiment Station at Auburn.
The plant is pollinated by the agency of the wind and of in-
sects, and he finds inter-crossing to have a material eflfect in
increasing the strength of the fibre.

Miss Ormerod will issue in a few days an abstract of infor.
mation on the history and habits of that seriously destructive
cattle-pest, the Warble Fly or Ox Bot Fly. The description will
be very fully illustrated, and will be an epitome of the knowledge
and experience gained up to the present time, and especially
during the years 1884 to 1S94. It will deal practically with
means of prevention and remedy. The publishers are Messrs.
Simpkin, Marshall, Hamilton, Kent, and Co.

.\N " .-\rtificial Spectrum Top," devised by Mr. C. E Ben-
ham, and sold by Messrs. Newton and Co., furnishes an in-
teresting phenomenon to students of physiological optics. The
top consists of a disc, one half of which is black, while the

114

NA TURE

[November 29, 1894

other half has twelve arcs of concentric circles drawn upon it.
Each arc subtends an angle of forty-five degrees. In the first
quadrant there are three such concentric arcs, in the next three
more, and so on ; the only difference being that the arcs are
parts of circles of which the radii increase in arithmetical pro-
gression. Each quadrant thus contains a group of arcs differ-
ing in length from those of the other quadrants. The curious
point is that when this disc is revolved, the impression of con-
centric circles of different colours is produced upon the retina.
If the direction of rotation is reversed, the order of these tints
is also reversed. The cause of these appearances does not
appear to have been exactly worked out.

The additions to the Zoological Society's Gardens during the
past week include a Black Lemur {Lemur macaco, { ) from
Madagascar, presented by Mr. Roche ; a Snowy Owl (A'yctea
scanditua), captured in mid-.\tlantic, 700 miles from land,
presented by Mr. Harston Eagle : two Levaillant's Cynictis
(Cynictis Itvaillanti), two Domestic Sheep (Ovis aria, var.),
two Puff' Adders ( Vipera arietans), a Cape Bucephalus
(Bucephalus capeusis), six Hispid Lizards {Agama hispida), five
Rough-scaled Lizards [Zonurus corydlus), a Delalande's Lizard
(Nucras delalandi), a Crossed Snake (Psammopltis crucifer) from
South Africa, two Bennett's Tree Kangaroos {Dendrolagus
itnne/iauus) from North Queensland ; an Allied Goshawk
(Astur afprcximans), three Long-necked Chelodines {Chelo-
dina lon^icollis), twenty-two Golden Tree Frogs (//j/a aurea),
seventeen While's Tree Frogs (Hyla dcrula) from Australia,
a Spix's Macaw (Ara spixi) from North Brazil, deposited ; two
Caroline Conures [Couurus carolinensis) from North America,
purchased; two Queensland Tree Kangaroos (Dendrolagtis
lumholtzi, i 9 ) from Queensland ; four Brush Turkeys
(Tategatla lalhami, 4 <J ) from Australia, received in exchange.

OUR ASTRONOMICAL COLUMN.

Tub Parallax of Neiiula k 2241. — .A.t the time when
Dr. Wilsing took photographs of the nebula B.D. -|- 4i°-4004
for the determination of parallax, he obtained also a series of
negatives of B.D. -i- 41 '•4773 (.4 2241) for the sane purpose.
This nebula is almost ring-shaped, and displays a cen.ral con-
densation. The latter appears more distinct on the photo-
graphic plates than can be seen by eye observations, and ils
contour is only sufficiently sharp for micromelric measurements
on the best plate-, so that the centre of the whole apparent disc
has been generally used. From June 1S92 to August of the
following year, 33 plates were obtained, 31 of which have been
used in this research. .Six comparison stars, the positions of
which were taken from the Bonn zones, have been adopted.
In ihi- account of the result obtained (Aslro. Nach. No. 3261),
Dr. Wilsing gives a table showing the deduced distances of the
nebula from the two comparison stars 3 and 6. A second table
contains ihe mean monthly values of these distances with their
differences from the whole mtan value obtained from all the
measuremeni^, toj;cihcr with the most probable errors of the
measurements.

The following table shows these differences between the toial
and monthly means for the two stars 3 and 6 :

IN.3I

1892 June 21 ... -003
July 13 ... -^o■|I
Aug. 9 ... +007
Sept. 25 ... -HO-OI
Oct. 4 ... -0'I3
Nov. 8 ... -(-0'20
Dec. 22 ... -o 53

1893 Feb. 4 ... -0-I3
July ... -O'oJJ
Aug. ... -053

tN-,61

Frob. enor.

•fo-28 ... ±0oS ... S

-l-o*o3 ... o'o6 ... 9

-0'04 ... 0-13 ... 2

-006 ... COS ... 5

-l-o'oi ... 0-13 ... 2

+ 003 ... O'lO ... 3

-044 oiS ... I

-034 ... 018 ... I

-019 ... o'i3 ... 2

-0-14 ... Q-iS ... I

suggests, to be cautiously dealt with, and he is led to conclude
from this series of measures that the relative parallax of this
nebula does not exceed one or two tenths of a second of arc.

.•V Possible New Zo.ne of Asteroids. — The secular
variations of the orbits of the four inner planets has lately
occupied Prof. Newcomb's attention, with the result that
several elements h-ive been found to vary in a manner un-
accounted for by existing theory. {Astronomical J ouriia!. No.
327.) "These anomalies," says Prof. Newcomb, "cannot be
simultaneously explained either by an intra-mercurial zone of
planets, by the action of matter rellecting the zodiacal light, or
by a deviation of gravitation from the usually accepted law.
The uncertainty as to the mass of Mercury makes the construc-
tion even of a working hypothesis difficult ; but apart from all
considerations of probabilities, .! priori, the hypothesis which
best represents observations, is that of a ring of planetoids of
small eccentricity a little outside the orbit of Mercury, and a
little more inclined to the ecliptic. The total m.iss of the ring
may range from one-fiftieth to, perhaps, one three-hundredth of
the mass of Venus, according to its distance from Mercury."
Prof. Newcomb intends to carefully investigate the matter in
order "to decide whether the results of the hypothesis are such
as to counterbalance its extreme improbability."

A New Co.met. — Edinburgh Circular, No. 43, dated
November 23, stales that a telegram received from the Central
Astronomical Station at Kiel announces the discovery of a very
faint comet, by Mr. Edward Swift, at 8 p.m., Californian time,
on the 20th inst. It was situated in Right .\scension, 22h. iSm.
24s., and South Declination, 13° 7', and was moving slowly
towards the east.

No. ..r

plates.

The«e differences, wh;n considered in relation with the
probable errori of the measurements, have as Dr. Wilsing

NO. 1309. VOL. 5 l]

A NEW SERIES OF NITROGEN COMPOUNDS.

A NOTHER new series of nitrogen compounds, containing
•**• four atoms of that element along with one atom of carboD
in a closed chain, are described by Prof. v. Pechmann and Ilerr
Runge in the current Bcrichte. They are termed " tetra-
zolium " compounds, and the parent base of the series is tetra-
zolium hydroxide, whose constitution is represented by the

^N-NH
formula HC; | ,, . The fundamental base itself has

'\

N N

\,

II •
OH

not yet been isola'ed ; the compounds prepared comprise the
derivative in which the two hydrogen atoms directly attached
to the two end nitrogen atoms are replaced by phenyl, together
with a large number of salts of this base, formed by replace-
ment of the hydroxy! by halogens or other acid radicles just as
in the case of metallic hydroxides. The hydrogen atom atl.\checl
to the carbon is likewise capable of replacement by many
organic radicles, so that a large number of still more compli-
cated bases havelikewisebeen prepared, together wilhtheir corre-
sponding salts. The hydroxides of this new series are character-
ised by possessing strong basic properties. They m.ay all be pre-
pared most conveniently from their chlorides, by the action upoi»
them of silver oxide. They are extremely soluble in water, but
are completely piccipilated from their solutions by ether. The
aqueous solutions absorb carbon dioxide ami behave very much
like caustic alkalies. They cannot, however, be crystallised,
forming rtslns upon concentration. The salts, on the other
hand, crystallise admirably ; they are usually soluble in water,
react neuiral to litmus, and possess a very bitter taste. Diphenyl
,,N— NPh

tetrazolium chloride, HCy

: taken as

•v I y-Di,. which may be I

^N -aC

CI
a typical salt of the .series, crystallises in colourless radiating
groups of needles very sensitive to light, which renders then>
yellow. The aqueous solution yields a ffesh. coloured precipi-
tate of a chloroplatinate with platinum chloride, and the double
salt may be crystallised from hot water. .V crystalline double
chloride is likewise produced with gold chloride. The addition
of a soluble nitrate or iodide causes the precipitation of the
difficultly soluble nitrate or iodide of the base. A solution of
iodine in potassium iodide precipitates an iodine addition pro-
duct, which can be crystallised from alcohol in beautiful brown
tabular crystals exhibiting a violet reflection. The parent base
is produced in solution upon the addition of silver oxide, silver

Il

November 29, 1894]

NATURE

115

chloride being likewise formed. The chloride is reduced by
' ammonium sulphide to a compound of the constitution :
^N— NHPh
HC,; , a substance which Prof. v. Pechmann has

\n NPh
previously described, and which is interesting as forming the
starting-point for the preparation of the new series. For the
chloride may at once be prepared from this latter substance by
oxidation with amyl nitrite and hydrochloric acid. The sub-
stance is readily prepared by the action of diazobenzene chloride
upon malonic acid, constituting the insoluble product of the
reaction. It is of considerable interest to observe that the
main product of the dry distillation of diphenyl tetrazolium
chloride is azobenzene.

THE SCIENTIFIC INVESTIGA TIONS OF THE
SCOTTISH FISHERY BOARD.

•yHE Twelth .Vnnual Report of the Fishery Board for Scot-
■'■ land (Part III. Scientific Investigations for 1893) con-
tains a quantity of new information upon fishery problems,
and marks an important stage in the history of the Board,
lowing to the successful inauguration during the past year of a
hatchery at Dunbar for the artificial propagation of ma-ine
focjd-fishes.

.\ number of important conclusions are formulated by the

rd upon various matters. In the first place, the closure of

territorial waters to beam-trawling is admitted to have had

ippreciable effect towards arresting the continued decline in

supply of flat-fishes, although the interdicted area has been

very large. The greater part of the territorial waters of the

K:ist Coast, the Firlh of Forth, and St. Andrews Bay have

been protected (except for experimental purposes) since l885,

and this area was greatly extended in 18S3, when practically

the whole of the territorial waters and several extensive bays

i (the Firth of Clyde and the Moray Firth) were closed against

I the operations of the beam-trawler. The reason for the failure

I of this method of protectiDn is sought for in the fact that the

I present protected area does not embrace the spawning grounds

"f fojd-fishes, except in the case of the Moray Firth. It is

-t unfortunate that, from lack of a safficiently seaworthy

^il, the Board has been unable to devote the same attention

I) the Moray Firth as to the Firth of Forth and St. .A.ndrews

I'.ay, for statistics upon the condition of the Moray Firth

lughout the year would have been invaluable. But it can

lefinitely asserted that the mere protection of areas that do

iiui include spawning grounds is practically useless to prevent

[depletion of the home fisheries. The recommendation of ihe

! recent Parliamentary Committee that the present territorial

: limit should be considerably extended, is accordingly endorsed ;

and, in order to ensure the enclosure of the more important

breeding-grounds, the Board emphasises its recommendation of

the previous year, that the limit of jurisdiction should be ex-

, tended to ten or twelve miles from shore.

i Experiments have been made upon the effects of alteration in
I the size of the mesh of the beam-trawl upon the capture of im-
i mature fish. It was found that, contrary to the opinion of most
' practical men at the recent Parliamentary inquiry, the size of
I the mesh has a moit appreciable influence in determining the
'size of the fish captured. Dr. Fulton's effective experimental
trawlings show that the proportion of fishes that escape through
the cod-end of the trawl increases greatly as the width of the
J meshes is enlarged.

I Prof. M'Intosh gives an interesting review of the trawling
I question in general, and includes a valuable sketch of the
changes which have taken place during the past ten years in
trawling-vessels and their apparatus. Reasons are adduced
which tend to show that line-fishing is quite as destructive as
trawling to immature round fishes, such as cod and haddock ;
and it is maintained that the perennial abundance of the floating
, fauna, of which larval stages of bjttoin-animals form so large a
proportion, is sufficient to prevent the trawling-grounds from
being depleted of fish-food to any serious extent.

The volume includes a number of papers of a more purely
biological character upon the development of fishes, on the in-
vertebrate fauna of the Firth of Forth and certain inland lochs,
on the oviposition and rate of growth of the sand-eel and certain
other fishes, and on some seasonal changes in the histology of

NO. 1309. VOL. 5 l]

fishes. Two papers on the osteology of the tunny and on the
anatomy of the pectoral arch in the gurnard seem to us to be
completely out of place in an official publication ostensibly
devoted to fishery investigations, with which they have nothing
to do.

Turning to Prof M'Intosh's "Remarks on Trawling,"
justifiable as his general position appears to be, he has, never-
theless, left himself open to criticism on a number of minor
points. It is difficult to reconcile with the statistics of the
f7a;7i!«(/ trawlings the Professor's remark that "the closure
of the inshore waters — e.g. St. Andrews Bay — must have
conduced to the prosperity of the turbot and the brill of
that neighbourhood, most of the turbot (ranging from 9 to II
inches) which formerly ivcrc captured by the trawler^ now being
unmolested " (p. 167). ForinDr. Fulton's introductory report
on the work of the CarlaiiJ it is stated that in St. Andrews
Bay, as in the Firth of Forth, there was an actual decrease in
1S93 of "turbot and brill" in the closed areas as compared
with 1892 (p. 26) ; and the decrease of flat-fishes in general
during the eight years of closure is demonstrated on p. 33.
Moreover, out of the twenty-four experimental trawlings con-
ducted by the Garland in the closed waters of St. Andrews
Bay in 1893 only two turbot, and no brill at all, were obtained.
Indeed, the average take of turbot was twice as great in the un-
protected as in the protected areas of the Bay (p. 42).

In one of the most interesting sections of his "Remarks"
(p. 1S4), Prof. M'Intosh discusses the "effect of trawling on
the invertebrate fauna of the sea-bottom (forming fish-food)."
It is full of valuable observations from the rich stores of the
Professor's experience, but, as an argument, seems to us to be
vitiated by a very questionable assumption which underlies it,
viz. that'all invertebrate life on the sea-bottom furnishes food
for fishes. Half the groups, at least, which are mentioned by
the Professor in this connection should, in our opinion, be
eliminated, viz. sponges, hydroids, anemones, alcyonaria, star-
fishes, balani, and ascidians, although we are quite prepared to
allow that now and then, in exceptional cases, particular species
of some of these groups may be swallowed by fishes. Therefore
the Professor's argument that the trawl causes little impoverish-
ment of the supply of fish-food, owing to the rapid powers of
growth and repair which the above groups (among some others)
possess, is seriously impaired.

In Mr. Harald Dannevig's Report (p. 21 1) we notice the
interesting observation that fishes which spawn during the night
in open ponds will do so during the day also if the pond be
darkened.

Coming to the biological investigations, we observe that Prof.
M'Intosh has overlooked (p. 227) the fact that the Norwegian
Topknot (Zeiigopterus norvegieiis) has been recorded by Mr.
Cunningham as occurring in considerable numbers at Plymouth
{Jour. M.B.A. ii. 1892, p. 325). In connection with Mr.
Sandeman's investigations on seasonal changes in the histology
of fishes, attention may be drawn to another paper by Air.
Cunningham (your. M.B.A. ii. 1891, pp. 16-421, in which a
number of remarkable histological changes are shown to take
place in the female conger during the period of the maturation
of her eggs.

The main results of Mr. Dickson's physical investigations
in the Faroe-Shetland seas seem to us to be of profound im-
portance. If, as he contends, a mass of .Atlantic water is every
year admitted through the Fanie-Shetland Channel, winds
round the Shetlands, and bores its way down the eastern coasts
of Scotland in the summer months, guided by a bank of dense
water in the upper regions of the North Sea, it is clear that we
have at once an explanation of numbers of isolated facts of
occasional or periodic distribution of pelagic animals in those
regions, which have hitherto seemed merely freaks of Neptune
or .Eolus. .And it cannot be doubted that a further exiensi.>n
of such investigations as Mr. Dickson has been carrying out
in H. M. S. Jaekal, if coupled with a corresponding survey of
the pelagic fauna, will provide the long-sought solution of the
migralions of the herring and other nomad fishes round our coasts.
In congratulating the Board upon its scientific achievemenis
for the year, we cannot help expressing our intense regret that
the recently vacant chairmanship was not offered by the Govern-
ment to Dr. John Murray. His experience and energy would
at all limes be invaluable, but at the present juncture, when so
many import.ant fishery problems of a physico-biological nature
are pressing for solution, the loss to the Board and (o the
country of his counsel and aid is incalculable. W. G.

Ii6

NA TURE

[November 29, 1894

SIR JOHN DOXXELL V OX TECHNICAL
EDUCATIOX.

A T the first ordinary meeting of the new session of the Society
•'^ of Arts, Major-General Sir John Donnelly delivered an
address in which he dealt with some points in the history of
the Socielj", and especially with those connected with the
promotion of education. The following is a condensed report
of his remarks bearing upon the development of technical
instruction : —

In 1S6S, a Cooference on Technical Education was held
by the Society of Arts, and shortly afterwards — on March 24,
1S6S — on the moiion of Mr., now Sir B. Samuelson, Bart., the
House of Commons granted a Select Committee, of which he
was appointed chairman, " to inquire into the provisions for
giving instruction in theoretical and applied science to the
industrial classes." The first three of their conclusions were—
(l) That, with the view to enable the working classes to benefit
by scientific instruction, it is of the utmost importance that
efficient elementary insiructioa should be within the reach of
every child ; (2) that unless regular attendance of the children
for a sufficient period can be obtained, little can be done in the
way of their scientific instruction ; (3) that elementary instruc-
tion in drawing, in physical geography, and in the phenomena
of nature should be given in elementary schools. Throughout
these discussions the object-lesson afforded by the Paris Exhi-
bition of 1867 was universally acknowledged to be the main
feature of the movement.

Sir John Donnelly brought before the Society in 18723 scheme
for examinations in technology, which were to be supplementary
to the examinations of the Science and Art Department. The
scheme did not meet with much enthusiasm, and manufacturers
set themsel%-es against it on the grounds that trade secrets
should not be the talk of the class-room. However, since then
the examinations have been very largely developed by the Ciiy
and Guilds of London Institute.

Owing to a set of circumstances, with which everyone is now
thoroughly conversant, there was, shortly after the passing of
the Technical Instruction Act, in 1S89, a great windfall for
technical instruction. Under the Customs and Excise Act of
1890, the residue, amounting to something over three-quarters
of a million of money in England and Wales, became applic-
able to technical education. It has been so applied very largely.
From a recent return it appears that, of the forty nine County
Councils, excluding Wales and Monmouth, forty-one are
applying the whole, and eight a part of the residue to technical
education. Of the sixty-one County Boroughs, fifty-three are
applying the whole, and seven a part of the residue to technical
education ; while in one case only (the County Borough of
Preston) the residue is being applied wholly to relief of rates.
Further than this, ten County Boroughs are, in addition, levy-
ing a rate under the Technical Instruction Acts.

For the year 1893-94, 'fie forty-nine County Councils have
allocated about £,^()^,(jao, and the County Boroughs about
;^l6l,ooo from the Customs and Excise grant, besides raising
over Z' 1 2. 700 by rates. This makes a total of almost exactly
;^626,ooo provided in England alone for technical instruction
(or the year, independent of the grants from the Science and
Art Department.

It is purely at the option of local authorities whether they
apply the "beer" money to technical education, or whether
they use it in relief of the rates. It is very gratifying to see the
extent to which they have devoted it to the former object, and
it shows that the operations of the Science and Art Depart-
ment, the Society of Arts, the City and Guilds of London, and
other bodies which had |)reviously been engaged In the uiove-
menl, have not been unfruitful. But unquestionably a great
danger lurks around a sudden outburst 01 zeal of this kind.
How far have the public generally been convinced of the efficacy
of science and art and technical instruction, and the advantage
of spending all the money on it, rather than in relief of rales ?
or how far have lliey been only momentarily carried away un-
willing captives at the chariot-wheels of the enthusiasts ? How
soon will the pendulum of public opinion which has been so
auddcniy and so severely forced in one direction swing back
again.' Or— a still greater danger — how scm will llie critic,
the cynic, and the "practical " man commence their innings by
asking to have the account balanced and the profit shown ?
There are already murmurings in the air: did not our fore-
fathers get on very well without technical education ? or how i>

it that we stand — or, at least, stood — at the head of manu-
facturing and commercial fame and engineering ability ?
At all events, if you cannot show any fruit let us have an
inquiry ; dig up the plant and have a look at its roots to see
that we have planted the right sort.

Now what is this "technical instruction " with which the
country is so much occupied at the present time ? It is defined
in the Act of 1889 as instruction in the principles of science
and art applicable to industries, and in the application of special
branches of science and art to specific industries or employ-
ments, as well as in modern languages and commercial and
agricultural subjects, but not in teaching the practice of any
trade, or industry, or employment.

The Act, in fact, provides for instruction in technology and
not in technics. Besides, though the definition clause is careful
to indicate that the principles of science and art are to be culti-
vated, the title of the Act appeals to the sympathy of the great
mass who always clamour for a short cut^some way for arriving
at the money-making application of science and of art without
that preliminary study which is so laborious and apparently un-
remunerative.

After dwelling upon changes of style in artistic work and
design, Sir John Donnelly went on to say that every now and
then we hear a great outcry against South Kensington and its
"system." .\nd if South Kensington now, why not in a few
years hence the technical schools and courses of instruction
which are being set up with so much care and thought in all
parts of the country ? This danger is already felt by many who
are interested in technical instruction. The Science and .\rt
Department couKl always point to the fact that, if its science
teaching was wrong, it erred in good company, for the sylla-
buses were prepared, and the examinations were conducted by
some of the most eminent men of science of the day.

But to whom can the local authorities under the Technical
Instruction .•\ct appeal ? It seemed to him that for their own
satisfaction, and lor the future stability of technical instruction,
they will desire, instead of remaining, as it were, isolated and
self-conlained. to have an influential examining and inspecting
board, to which they might refer, if they found it desirable, for
assistance ami advice. There are at present several bodies
partially covering the ground — but only partially, and there is
ttie great disadvantaije of a want of unity. He threw out the
suggestion that the Society of Arts, which is at present cover-
ing part of the field, should take the initiative in bringing all
these bodies together, so that they may form some kind of joint
board, or a! least co-operate.

T^

THE BA TTLE OF THE FORESTS}

I.

HE earth is a potential forest. Given time, freedom from
geologic revolutions and from interference by man, the
tree growth must finally dominate everywhere, with few excepted
localities.

Its perennial nature and its elevation in height above all other
forms of vegetation, together with its remarkable recuperative
powers, assure to the arborescent flora this final victory over its
I competitors.

So impressed was Dr. Asa Gray with the persistence of indi-
vidual tree life that he questioned whether a tree need ever die :
" For the tree (unlike the animal) is gradually developed by the
successive addition of new parts. It annually renews not only
its buds and leaves, but its wood and its roots ; everything,
indeed, that is concerned in its life and growth. Thus, like the
fabled .ILson, being restored from the decrepitude of age to
the bloom of early youth, the most recent branchlels being
placed by means of the latest layer of wood in favourable com-
munication with the newly-formed roots, and these extending at
a corresponding rate into fresh soil, why has not the tree all the
conditions of existence in the thousandth that is possessed of
in the hundredth or the tenth year of lis age?

'The old and central part of the trunk may, indeed, decay,
but this is of little moment, so long as new layers are regularly
formed at the circumference. The tree survives, and it is
difficult to show that it is liable to death from old age in any
proper sense of the term."

' A lecture Jclivcrcd by Prof. U. E. Fcrnow. Chief of tlic Korestry
Depirimcnl of Agriculture. U.S.A., during ifie Brooklyn meeting of the j

American Atsociaiijn for tiie Advancement cjf Science..

NO. 1309, VOL. 51]

November 29, 1894]

NATURE

i'7

However this may be, we know trees succumb to external
luses. Nevertheless, they are perennial enough to outlive
;.ight else, " to be the oldest inhabitants of the globe, to be
more ancient than any human monument, and exhibit in some
of the survivors a living antiquity compared with which the
mouldering relics of the earliest Egyptian civilisation, the pyra-
mids themselves, are but structures of yesterday. ' The dragon
'rees, so called, found on the island of Teneriffe, off the African
oast, are believed to be many thousand years old. The largest
., only 15 feet in diameter and 75 feet high. Our sequoias are
lore rapid growers, and attain in 3000 to 4000 years, which
ii.ay be the highest age of living ones, more than double these
i.mensions.

While this persistence of life is one of the attributes which
in the battle for life must count of immeasurable advantage,
ihe other characteristic of arboreal development, its elevation
in height above everything living, is no less an advantage over
x\\ competitors for light, the source of all life. Can there be
ny doubt that in this competition size must ultimately triumph,
,ind the undersized go to the wall ?

Endowed with these weapons of defensive and offensive war-
'are, forest growth, through all geologic ages during which the
•arth supported life, has endeavoured, and no doubt to a degree
succeeded, in gaining possession of the earth's surface.

As terra Jlrma increased emerging in islands above the ocean,
so increased the area of forest, changing in composition to
irrespond with the change of physical and climatic conditions.
.\3 early as the Devonian age, when but a small part of our
-mtinentwas formed, the mud flats and sand reefs, ever in-
casing by new accumulations under the action of the waves
.nd currents of the ocean, were changed from a bare and
ifeless world above tide level to one of forest-clad hills and
Inles.

Not only were such quaint forms as the tree rushes Calamites,

I.ei.idodendron and Sigillaria present, but the prototype of our

ine, the Dadoxylon, had made its appearance.

The same class of flowerless plants known as vascular

lyptogams, with the colossal tree ferns added, became more

umerous and luxuriant in the Carboniferous age, as well as the

lowering .Sigillaria and coniferous Dadoxylon. This vegetation

,irobibly spread over all the dry land, but the thick deposits

if vegetable remains accumulating in the marshy places under

i^nse jungle growth and in shallow lakes with floating islands,

ere tinally, in the course of geologic revolutions, turned into

lie great coal fields.

In those and subsequent geologic times some of the floral
ypes vanished altogether and new ones originated, so that at
'.t; end of Mesozoic times a considerable change in the land-
j.ipe had taken place.

In addition to coniferous trees, the palms appeared, and also
the first of angiosperms, such as the oak, dogwood, beech,
"■plar, willow, sassafras, and tulip tree. Species increased in
imbers, adapted to all sorts of conditions ; the forest in a most
..uied and luxuriant form climbed the mountain-sides to the very
crests, and covered the land to the very poles with a flora of
tropical and semi-tropical species.

Then came the levelling process and other changes of post-
Tertiary or Quaternary times ; the glaciation of lands in
northern latitudes, with the consequent changes of climate,
which brought about corresponding changes in the ranks of the
forest, killing out many of the species around the north pole.
Only the hardier races survived, and these were driven south-
ward in a veritable rout.

When these boreal times subsided in a degree, the advance
of the forest was as sure as before, but the battle order was
somewhat changed to suit the new conditions of soil and
climate. Only the hardiest tribes could regain the northernmost
posts, and these found their former places of occupancy changed
by fluvial and lacustrine formations and the drifts borne and
deposited by the ice-sheets, while some by their constitution
were entirely unfitted from engaging in a northern campaign, or
found insurmountable barriers in the refrigerated east-west
elevations of Europe and Western Asia.

In addition, there had come new troubles from volcanic erup-
tions, which continually wrested the reconquered ground from
\he persistent advance guards of the arboreal army, annihilating
them again and again.

Finally, when the more settled geologic and climatic con-
ditions of the present era arrived, and the sun rose over a
world ready for human habitation, man found what we are

NO. 1.^09, VOL. 5 l]

pleased to call the virgin forest — a product of long- continued
evolutionary changes — occupying most, if not all the dry land,
and ever intent upon extendmg its realm.

This prehistoric view of the battle of the forest cannot be left
without giving some historic eviilences of its truth.

Not only have palaeobotanists unearthed the remnants of the
circumpolar flora, which give evidence that it resembled that of
present tropic and semi-tropic composition, but they have also
shown that sequoias, magnolias, liquidambars and hickories-
existed in Europe and on our own continent in regions where
they are now extinct. We have also evidences of the repeated
successes and reverses of the forest in its attempts to establish
itself through long geologic transformations.

One of the most interesting evidences of these vicissitudes in
the battle of the forest is represented in a section of Amethyst
.Mountain in Yellowstone National I'ark, exhibiting the remains
of fifteen forest growths, one above the other, buried in the
lava. Again and again the forest subdued the inhospitable ex-
coriations ; again and again it had to yield to superior force.

Among these petrified witnesses of former forest glory, mag-
nolia, oak, tulip tree, sassasfras, linden and ash have been iden-
tified, accompanying the sequoia in regions where now only the
hardiest conifer growths of pines and spruces find a congenial
climate.

As the forest formed and spread thus during the course of
ages, so does it form and spread to-day, unless man, driven by
the increasing needs of existence, checks its progress and reduces
its area by the cultivation of the soil. This natural extension
of the forest cover or afforestation takes place readily when-
ever soil and climate is favourable, but it is accomplished
just as surely, though infinitely slower, in unfavourable situa-
tions. On the naked rock, the coarse detritus and gravel beds,
on the purely siliceous sand deposits of river and ocean, or in
the hot dry plains, the preliminary pioneer work of the lower
vegetation is required. .A.lgie, lichens, mosses, grasses, herbs,
and shrubs must precede to cultivate the naked rock, to mellow
the rough moisture by shading the ground, and gradually render
it fit for the abode of the forest monarch. The army of soil-
makers and soil-breakers, the pioneers, as it were, of the forest,
are a hardy race, making less demands for their support than
those that follo«-. They come from different tribes, according
to the soil conditions in which they have to battle.

The aspen [Popiihis tremuloides) is one of these forerunners,
which is readily wafted by the winds over hundreds of miles,
re.adily germinates and rapidly grows under exposure to full
sunlight, and even now in the Rocky Mountains and elsewhere
quickly takes possession of the areas which man has ruthlessly
destroyed by fire. This humble and ubiquitous, but otherwise
almost useless, tree is nature's restorative, covering the sores and
scalds of the burnt mountain side, the balm poured upon
grievous wounds. Though short-lived, with its light summer
foliage turning into brilliant golden autumn hues, it gives
grateful shade and preserves from the thirsty sun and wind some
moisture, so that the better kinds may thrive and take its place
when it has fulfilled its mission.

One of the shrubs or half-trees which first take possession of
the soil in the western mountain country is the so-called moun-
tain mahogany [Ccreocar/iis h-dif alius), covering the bared
slopes after the lire has killed the old timber.

In other regions, as on the prairies of Iowa and Illinois, hazel
bushes, or in the mountains of Pennsylvania and the .\lleghanies
in general, ericaceous shrubs like the laurel and rhododendrons
or hawthorn, viburnum and wild cherry are the first comers,
while along water-courses alders and willows crowd even the
water into narrower channels, catching the soil which is washed
from the hill sides and increasing the land area.

One of the most interesting soil-makers, wresting new terri-
tory from the ocean itself, is the mangrove along the coast of
Florida. Not only does it reach out with its aerial roots, entang-
ling in their meshes whatever litter m.iy float about, and thus
gradually building up the shore, but it pitches even its young
brood into the advance of the battle, to wrestle with the waves,
and gain a foothold as best it may.

Not less interesting in this respect is that denizen of the
southern swamp, the bald cypress, with its curious root excres-
cences known as cypress knees, which, whatever their physio-
logic signilicance, are most helpful in expediting changes of
water into land sufficiently dry to be capable of supporiiiig the
more fastidious species in regard to moisture and conditions.

On the dry hot mesas, and in the arroyos of the south-'western

iiS

NATURE

[November 29, 1894

tier of our States and Territories, we meet a different set of
skirmishers following up the huge cacti and agaves, which to-
gether with the tree yuccas, penetrate into the very desert. In
these regions the mesquite or algaroba and others of the acacia
tribe form the second phalanx, as it were, gradually advancing
their lines in spite of adverse conditions. In other regions the
pine, satisfied with but scanty favour of soil moisture, and the
spruce, able to sustain life in shallow soil, and the lir, in the
higher, colder, and wetter elevations, sometimes much stunted,
form the skirmish line. These improve the soil in its moisture
conditions by their shade, and by the foliage and litter falling
and decaying they deepen the soil, forming a humus cover. The
duff that is found covering the rocky subsoil of the Adirondacks
is formed in this way at the rate of about one foot in 500 years.
They are soon followed by the birch, maple, elm, and ash, and
in moister situations by the oak — first, that hardy pioneer, the
black oak tribe, and then the more fastidious white oak, with
whom the slower but persistent hickories, beeches, and other
shade-enduring species begin to quarrel for the right of occu-
pancy of the ground, until the battle is no longer that of the
forest against the elements and lower vegetation, but between
the mighty conquerors themselves. This struggle we can see
going on in our primeval forests, wind, storms, and decay acting
as allies now to one, now to the other side, and thus changing
the balance of power again and again.

In this struggle for supremacy between the different ar-
borescent species the competition is less for the soil than for the
light, especially for tree growth. It is under the intluence of
light that foliage develops, and that leaves exercise their functions
and feed the tree by assimilating the carbon of the air and
transpiring the water from the soil. The more foliage and the
more light a tree has at its disposal, the more vigorously it will
grow and spread itself.

Now the spreading oak or beech of the open field finds close
neighbours in the forest, and is narrowed in from all sides and
forced to lengthen its shaft, to elevate its crown, to reach up
for light, if it would escape being overshadowed, repressed, and
perhaps finally killed by more powerful densely-foliaged
competitors.

The various species are differently endowed as regards the
amount of light which they need for their existence. Go into
the dense foiest and see what kinds of trees are vegetating in
the dense shade of the older trees, and then go into the opening
recently made, an abandoned field or other place, where the
fall benefit of light is to be had by all alike, and one will find
a different set altogether occupying the ground and dominating.
In the first case there may be found, perhaps, beech and sugar
maple or fir and spruce ; in the second case aspen, poplar,
willow, soft maple, oak or pine, tamarack, &c.

All trees thrive ultimately best in full enjoyment of light.
But some, like those first mentioned, can at least subsist and
their foliage functionate with a small amount — they are shade-
enduring kinds, usually having a dense foliage, many leaves,
and each one needs to do but little work — and exert considei»
able shade when fully developed. Those last named, however,
are light-needing kinds, and having less foliage, cannot exist
long without a considerable amount of light.

To offset this drawback in the constitution of these latter,
nature has endowed them as a rule with the capacity of rapid
height growth, to escape their would-be suppressors ; but again,
what they have gained in the rapidity of development they
lose in the length of life. They are mostly shortlived species,
while the shade-enduring are generally slower growers, but
persistent and long-lived. Some kinds, like most of the oaks,
stand between the two ; while exhibiting a remarkable capacity
of vegetation in the shade, they are really light-needing species,
but comparatively slow-growers and long lived. One of the
same species behaves also somewhat differently under different
soil and climatic conditions; for instance, as a rule, the light-
needing species can endure more shade on moist soils, and the
thadc enduring require more light on drier soils.

In liie earliest stages of life the little seedlings of most trees
require partial shade, and are quite sensitive in regard to light
and conditions. Some have such a small range of light and
shade endurance that, while there may be millions of little
seedlings sprouted, they will all perish if some of the mother
trees are not removed and more light given ; and they will
pcri-sh equally if the old growth is removed too suddenly, and
the delicate leaf structure, under the influence of direct sunlight,
is made to exercise its functions beyond its capacity.

Left to itself the forest grows up, and as the individual trees
develop, each trying to hold its ground and struggling for light,
a natural thinning lakes place, some trees lagging behind in
growth and being shaded out, until in old age only as many
trees remain as can occupy the ground without incommoding
each other.

This struggle among the individuals goes on during their
entire life. Some few shoot ahead, perhaps, because of a
stronger constitution or some favourable external cause, and
over-tower their neighbours. These, lagging behind, fall more
and more under the shading influence of their stronger neigh-
bours until entirely suppressed, when they only vegetate until
they die. The struggle continues, however, among the dominant
class, and it never ends.

Thus the alterations of forest growth take place, oak follow-
ing pine, or pine following oak ; the poplar, birch and cherry
appearing on the sunny burns, or the hickory, beech, and
maple creeping into the shadier pine growths. While in
the eastern forests under natural conditions the rotation of
power is accomplished in at least from 300 to 500 years, the old
monarchs of the Pacific, towering above all competitors, have
held sway 2000 or more years. In this warfare, with changes
in climatic and soil conditions going on at the same time, it may
well occur that a whole race m.iy even be exterminated.

The study of the form.itive period of the forest is necessary in
order to show clearly that the virgin forest is a product of long
struggles, extending over centuries, nay, thousands of years.
Some of the mightiest representatives of the old families,
which at one time of prehistoric date were powerful, still
survive, but are gradually succumbing to their fate in our era.

The largest of our eastern forest trees, reaching a height of
140 feet and diameters up to twelve feet, the most beautiful and
one of the most useful, the tulip tree (Liriodendroii lulififiia),
is a survivor of an early er.i, once widely distributed, but now
confined to eastern North -Vmerica, and doomed to vanish
soon from our woods through man's improper partisanship.

Others, like the Torreya and Cupressus, seem to have suc-
cumbed to a natural decadence, if we may judge from their
confined limits of distribution. So, too, the colossal sequoias,
remnants of an age when things generally were of larger size
than now, appear to be near the end of their reign, while the
mighty taxodium or bald cypress, the big tree of the East, still
seems vigorous and prosperous, being able to live with wet feet
without harm to its constitution, weird with the grey tillandsia
or .Spanish moss.

Having thus scanned through the traditions of unwritten
history of the battle of the forest, having seen some of the
combatants in the struggle, and learned something of their
methods of conquering the earth and each other, we may take
a look at the condition of things on the North American con-
tinent as it presumably was in the beginning of historic times
or within our century.

As far as occupancy of the soil by the forest is concerned,
we find that the struggle had not yet been determined in its
favour everywhere. While a vast territory on the Atlantic side
and a narrower bell on the Pacific Coast, connected by a broad
belt through the northern latitudes, was almost entirely under
its undisputed sway, and while the backbone of the continent,
the crest and slopes of the Rocky Mountains, was more or less
in its possession, there still remained a vast empire in the
interior unconquered.

Of parts of this territory we feel reasonably certain from
strong evidences that the forest once occupied them, but has
been driven off by aboriginal man, the firelnand taking sides
with the grasses, and the buffalo probably being a potent
element in preventing re-establishment. In other parts it is
questionable whether the lines along the river-courses, the
straggling trees on the plateaus and slopes, are remnants of a
vanquished army or outposts of an advancing one. In some
parts, like the dry mesas, plateaus and arroyos of the interior
b,asin and the desert-like valleys toward the southern frontiers,
it may reasonably be doubled whether arborescent flora has
more than begun its slow advance from the outskirts of the
established territory.

Certain it is that climatic conditions in these forestless regions
are most unfavourable to tree growth, and it may well be ques-
tioned wbttther in some parts the odds are not entirely against
the progress of the forest.

Temperature and moisture conditions of air and soil deter-
mine ultimately the character of vegetation, and these are

NO. 1309, VOL. 51]

li

November 29, 1894]

NATURE

119

dependent not only on latitude, but largely on configuration of
the land, and especially on the direction of moisture-bearing
winds with reference to the trend of mountains.

The winds from the Pacific Ocean striking against the coast
range are forced by the expansion and consequent cooling to
give up much of their moisture on the windward side ; a
second impact and further condensation of the moisture
takes place on the Cascade range and Sierra Nevada. On
descending, with consequent compression, the wind becomes
warmer and drier, so that the interior basin, without additional
sources of moisture and no additional cause for condensation, is
left without much rainfall and with a very low relative
humidity, namely, below 50 per cent. The Rocky Mountains
finally squeeze out whatever moisture remains in the air
currents, which arrive proportionally drier on the eastern slope.
This dry condition extends over the plains until the moist
currents from the Gulf of Mexico modify it. Somewhat
corresponding, yet not quite, to this distribution of moisture,
the western slopes are found to be better wooded than the
eastern, and the greater difficulty of establishing a forest cover
here must be admitted ; yet since the forest has the capacity of
creating its own conditions of existence by increasing the most
important factor of its life, the relative humidity, the extension
of the same may only be a question of time.

Temperature extremes, to be sure, also set a limit to tree
growth, and hence tl G so-called timber line of high mountains,
which changes in altitude according to the latitude.

If now we turn our attention from the phyto- topographic
consideration of the forest cover to the phyto-geographic and
botanical features, we may claim that the North American
forest, with 425 or more arborescent species, belonging to 158
genera, many of which are truly endemic, surpasses in variety of
useful species and magnificent development any other forest of
the temperature zone, Japan hardly excepted. In addition there
are piobably nowhere to be seen such extensive fields of distri-
bution of single species.

These two facts are probably explained by the north-and-
south direction of the mountain ranges, which permitted a re-
establishment after the Ice Age of many species farther north-
ward, while in Europe and the main part of Asia the east-west
direction of the mountains offered an effectual barrier to such
re-establishment, and reduced the number of species and their
field of distribution ; nor are the climatic diflferences of different
latitudes in North America as great as in Europe, which again
predicates greater extents in the fields of distribution north and
south. On the other hand, the dilferences east and west in
floral composition of the American forest are greater than if an
ocean had separated the two parts instead of the prairie and
plains. This fact would militate against our theory ihat the
intermediate forestless region was or would be eventually
forested with species from both the established forest regions,
if we did not find some species represented in both regions and
a junction of the two floras in the very region of the forestless
areas.

{To be continued.)

SOCIETIES AND ACADEMIES.

London.

Zoological Society, November 20. — Sir W. H. Flower,
K.C.B., F.K.S., President, in the chair. — Mr. F. G. Parsons
read a paper on the anatomy of Athcrttra africaua^ compared
with that of other porcupines. In addition to the points men-
tioned by Drs. Gray and Giinther, as differences between the
skulls of A. africaiui and A. niaciiira, the arrangement of the
fronto-nasal suture, the position of the maxillo-malar suture,
and the frequent presence of an " »j anti-epilepticum" were
noticed. — A communication from Mr. J. T. Cunningham
treated of the significance of diagnostic characters in the
Pleuronectidie. — Mr. A. Smith Woodward read a description
of the so-called Salmonoid fishes of the English Chalk, dealing
with the osteology of OsmtroiJes Icioesicnsis, Elopopsis crassiis,
and Aiilolepis typiis. — Mr. W. Garstang read a paper on the
Gastropod Colpodaspis pusilla of Michael Sars. lie described
a specimen of this rare moUusk found by him at Plymouth
in the early part of the year. — A communication from Mr.
A. D. Bartlelt gave an account of the recent occurrence
in the Society's menagerie of a case of one boa swallowing

another of nearly equal size.— A communication from Prof. R.
Collett contained a description of a new Agonoid fish from
Kamtschatka, proposed to be called Agoiius gilberli.

Royal Meteorological Society, November 21. — Mr. R.
Inwards, President, in the chair.— Dr. H. B. Guppy read a
paper on suggestions as to the methods of determining the
influence of springs on the temperature of a river as illustrated
by the Thames and its tributaries. The methods suggested
were (l) comparison of the curves of the monthly means of the
temperatures of the air and of the water for the river under
observation with those of a river beyond the controlling
influence of springs ; (2) comparison of the monthly means of
the temperature of the river under investigation with that of a
river beyond the control of the springs ; (3) comparison of the
range of the monthly means of the river temperature with that
of the air in the shade ; (4) comparison of the daily range of
water temperature at different stations along a river's course ;
(5) comparison of sunrise observations made at different
stations along a river's course ; (6) comparison of observations
made at difterent stations along a river's course at the hour of
maximum temperature ; (7) comparison of the results obtained
from a single series of observations made in one day along the
whole course of a small tributary like the Wandle, or along the
upper course of a larger tributary as the Kennet ; and (8) deter-
mination of the distance from its sources at which the river begins
to freeze. — Mr. Eric S. Bruce exhibited and described some
lantern slides showing the disastrous effects of the great gale of
November 17 and 18, 1893, upon trees in Perthshire, Scotland. —
Mr. Alfred B. AYollaston gave an account of the formation of
some water-spouts which he had observed in the Bay of Bengal.

Cambridge.

Philosophical Society, November 12. — Prof. J. J. Thomson,
President, in the chair.— On the inadequacy of "the cell theory
and on the development of nerves, by Mr. A. Sedgwick. The
I author pointed out that the cell-theory, in so far as it implied that
j the organism was composed of cell-units derived by division
from a single primitive cell-unit, the ovicell, would not bear the
scrutiny of modern embryology, and that in fixing men's
attention too much upon the cell as a unit of structure, it had
had a retarding influence on the progress of the knowledge of
structure. He illustrated this latter point by reference to the
current ideas on two important subjects : the structure of the
embryonic tissue called mesenchyme, and the development of
nerves. The mesenchyme is not composed of separate branched
cells, but has rather a spongy or reticulate structure, and is
continuous both with ectoderm and endoderm. Nerves do
not develop as outgrowths of the central organ, but arise in
situ from the mesenchyme. — Note on the evolution of gas by
water-plants, by Mr. F. Darwin.

Paris.
Academy of Sciences, November 19. — M. Lcewy in the
chair. — After the reading of \.\i& prods verbal, the meeting was
adjourned as a mark of respect to the late Czar of Russia.

Amsterdam.

Royal Academy of Sciences, October 27.^Prof. Van de
Sande Bakhuyzenin the chair. — Mr. Franchimont, in presenting
Mr. H. van Erp's thesis for the Doctorate in Chemistry at the
University of Leyden, entitled " Studie ober ahphatische
nitraminen," described it as a summary of all the known acid
and neutral nitramines and nitramides, and also of their modes
of formation. In dealing with the action of water, acids and
alkalies on these bodies, Sir. van Erp considers them as derived
from the amide of nitric acid, and compares them to the analogous
derivatives of nitrous acid, hypochlorous acid, &c. For ex-
perimental purposes he made the unknown butyl- and hexyl-
derivatives ; nine urethanes, seven nitro-urethanes, four acid
nitramines with several salts, two mixed neutral nitramines. He
failed, however, to obtain nitro-compounds of the tertiary butyl
amidoformates. He has observed that while the potassium
salts of the acid nitramines yield the neutral methyl-derivatives
hy the action of melhyliodide, the silver salts produce an
isomeric methylated nitramine, or a mixture of the two. Similar
observations in the case of the salts of phenylnitramine were
made later by Bamberger. The behaviour of acid nitramines
lowards dilute sulphuric acid was studied on hexylnitramine,
the result being N^O, two hexanoles, a primary and a secondary

NO. 1309, VOL. 51]

120

NATURE

[November 29, 1694

(2 ? , hexene (l^ and a dihexylic ether. Mr. van Erp has also
observed the behaviour of neutral nitramines with alkalies.
Dimethylnitramine gives nitrous acid, monomelhylamine,
formic acid (and methyl alcohol ?). Diethyl- and dipropyl-
nilramine seemed not to be changed. Normal butylmethyl-
nitramine, less easily than dimethylnitramine, gives nitrous
acid, butylamine, formic acid (and methyl alcohol?). It
therefore seems that mixed nitramines give the amine with the
greatest alkyl, or the methyl radical is most easily separated
from the nitrogen. — On quadrinodat quintics, by Mr. Tan de
Vrie^. — On the cranial nerves of vertebrates in amphioxus, by
Mr. van Wijhe. The olfactory nerve represents a type of its
own. The ventral nerves, or nerves of the myotomes, do not
exhibit special characteristics. Among the dorsal or septal
nerves, the trigeminal, facial, glossopharyngeal and vagus
ner^•es could be recognised with more or less probability, chiefly
by their relations to the branchial clefts, the first of which on
the left side becomes the opening of the velum.

DIARY OF SOCIETIES.

LONDO.N.

THURSDA y, November 39.
Sanitary I.sstitutb, at 3. — Workers io Copper, Zinc, Brass, and Tin :
Dr. R. M. Simon.

FR/DAV, November 30.
RotalSocistv, at 4.— Anniversary Meeting.
Institl'tion op Civil Engineers, at 8.— Sub-aqueous Excavation at

Ncwry: C. H. Ollcy.
Sanitary Institute, at 8.— Sanitary Law : Prof. A. Wyntcr BIyth.

S[/.\'DAi% Decembkr a.
SuNDAT Lecture Society, at 4. — Village Life in India: Mr. R.W. Frazer.

MONDAY, DbCEMBER 3.

SociKTV OF Arts, at S. — Modem Developments in Explosives : Prof.
Vivian H. Lewes.

SociBTVor Chemical lKDUSTRv(BurIinKtnn House), atS —The Rational
Sterili-^aiion of Alimentary Liquids : Mr. E- W. Kuhn (of Paris). — \i\
Invcsiigationof the Natural Sodium Sulphate Lakes of Wyoming. US. A. :
Dr. D. H. Aiifield. — Specimens of Inrtia-mbbcr. and Petroleum Oil,
Varnish, and Soap will be exhibited by Mr. Thos. Christy.

Victoria iNSTiTUTE.at 4.30.— Semitic Languages: Mr. T. G. Pinches.

TUESDAY, December 4.

Zoological Society, at 8.30.-00 some Points in the Anatomy of
(Jmithorh^-nclius paradoxus : Mr. T. M.inners Smith.— On certain Points
in the Visceral Anatomy nf Orniihorhynchus : Mr. F. E. Beddard,
F. K.S. — On M>me Remarkable Corals of Great Size from North- West
Australia: Prof. F. Jeffrey Bell.— Second Report on Additions to the
Lizard Collection in the Naiui.tl History' Museum: Mr. G. A. Boulenger,
F.R.S.

iNsr.TiTiON OF Civil Engineers, at 8.— The Machitwry of War-Ships :
Mr. AlbenJ. Durston. -Colliery Surface-Works: Mr. E. H. Wain.

Royal Statistical Society, at 4.45— The Eleventh United States
Census: Hon. R. P. Porter.— Kxhibition of the Hollerith Electrical
Counting Machine :«Dr. H. Hollerith.

lYEDXESDAY, December 5.

Society or Arts at S.— Fire Protection : Edwin U. Sachs.

Geoliicical Societv, at 9. — Supplementary Note on the Narborough
District (Leicestershire): Piof. T. G. Bonney. F- R.S.— The Tarns of
UkeUnd: .Mr. J. E. .Marr. F.RS.-The Marble Beds of Natal: Mr.
Djvi '. I rji.rr —1 tr . rlpiion of a Ncw Instrument for Surveying by the
Ai'' '1 some Observations uiH)n the Applicability of the

In-r I Purposes: Mr. J. Bridges Lee.

Ent._ : ., at 8— A List of the L^-pidoptera of ihe Khasia

Hili«, fart IJl.: Colonel Charles Swinhoe. — A Monograph of British
Braconidx, Part Vf. : Rev. T. A. Marshall. — On the Longicorn Cole-
»pirr^ .A ri,- UV^t India Islands: Mr. Charles J. Gahan. — Notes on the
iu- .«nd Eating Habit of Scricomyrmex opacus, Mayr. : Mr.

F. '•'' 1 App.'xrrnt Case of Sexual Preference in a Male Insect :

Pr^:. .. ... 1 ...;.n. I-.R.S.

rZ/i/^.S'ZJWr, December 6.

.'"'. — Experimcnial Researches on Vegetable Assimila-
No I. On a New Method for Investigating the
■-1 of Plants. No 2 : i)n the Paths of fLxscous
al Leaves and the Atmosphere : Mr. F. F. Black-

. at4

at 4.30.— Roman and British Indian Systems of
. l.<e-Wamer, C.S."

OVAL S'-iriPT^*

tifin '

Car

Kv

man.
SociiTV or Arts,

Government : Hod. W.
Linnran .Society, at 8. — A New Revision o' Dipierocarpex, with Lantern

Slides : Sir !>. Brandts, F.R.S.— On the Spinning Glands in Phryous :

M:. H. M. Bernard.
Chemical Society, at 8.— T>ir l\c of the GIi.be In the Study of Crystal-
lography: J V Buchan.-tn, F. R.S. — Latent He.ni of Fusion: Mr. H,

Crompton. — New Method of F'rrp.iring Dihydroxytariaric Acid: Mr. H.

J. H. Fcnion, — fc*i«oua; •>! d rtcp«: Mr. A. C. Chapman.
LnHi>ON Institution, ac 6.— The Fauna of Rivers and Lakes: Prof.

Sydney Hick son.

FRtDA >', \H' KMUHR 7.

Royal Imstitutiok, at 5.— General Monthly Meeting.

Gkol/>oi«.ts' A^«.ociation. .-it 8 — Noic -to Megalovaurian Teelh. dis-
covered by Mr. J. Alsioae in the Portlandianof Ayleshury : Mr. .A. Smith
Woodward.— On the Geology of the Si. Goihard Pass: Mr. H. W.
M Dock Ion.

SATURDAY^ Dbcimber 3.

ROTAL BOTAHIC SoCIKTV, at 3.43.

NO. 1309, VOT.. 51]

BOOKS, PAMPHLETS, andSERIALS RECEIVED

BojK<. — Imperial University of J.apan, Calendar 1593-4 (Tky
Maruya).— Catalogue of the Snakes in the British Museum (Natural
History-): G. A. Boulenger, Vol. 2 (London).— The Flower of the Ocean,
the Island of Madeira : Surg eon -General C A. Gordon CBaillic'e). — Topo-
graphische Anatomic des Plerdes : Ellcnbur^er and Baum. Zweiter Teil
(Berlin, Parcy). — Buiterfiies and Moths (British): W. Furneau.v (Long
mans).

Pamphlets.— Sulk Oscillazioni Eletiriche a Piccola Lunghezia d'Onda-
%fi. : Prof A. Kighi (Bologna). — North of England Institute of Mining and
Mechanical Engineers : Report of the Procecding^v of the Flamcless Ex-
plosives Commiiicc. Part i. Air and Combustible Ga-ies : A. C. Kayll
(Reid). — Rcsultate der im Sommer 1893 in dem Ni>rdlichsten Theile Nor-
wegcns ausgefuhrtcn Pendelbeobachtungen : O. E. Schiol? (Kristiania.
Dybwad).

Serials.— Casscll's Maganne, December (Cassell). — Proceedings of the
Aristotelian Society. Vol. 2, No. 3. Part a (Williams). — Transactions and
Proceedings of the Botanical Society of Edinburgh, Vol. .\.v. Part i (Edin-
burgh).— Proceeding> of the American Academy of Arti and Sciences, new
series. Vol. xxi. (Boston). — Brain. Part Ixviii. (Macmillan). — Kr>' pi oga men-
Flora von Schlesien, iti. Band, a Halftc, 3 Liefg. (Brc-ilau, Kern). — Journal
of the Institute of Jamaica, September (Sotheran). — Longman's Magazine,
December (Longmans) — Chambers's Journal, December (Chambers). —
Natural Science, December (Macmillan). — Good Words, December and
Christmas (Isbistcr).— Sunday Magazine, December and Christmas (Isbis-
ter). — Ci:ntur>' M.tgazine, December (Unwin). — Humanitarian. December
(HutchinstJn). — Udgivct af den Norske Gradm-ialings-Konimission. \'aiid-
stansobscTvaiioncr. v. Hefie (Christiania, Fabritiiis) — Botanische Jahr-
bucher, &c., Zwanzigster Band, i and 2 Heft (Leipzig, Engelmann).

CONTENTS. PAGE

Locomotive Construction. Ry N. J. Lockyer ... 97

Indo-Malayan Spiders. By R. I. Pocock 99

The Plateau Region of Southern France. By

Canon Bonney, F.R.S 100

Our Book Shelf:—

Ziwet : " An Elementary Tieatise on Theoretical

Mechanics." — G loi

Aubertin : " By Order of the Sun to Chile to see his

Total Eclipse', April 16, 1893" 101

Schmidt: ■' Keise nach SUdindien " loi

Step: " By Vocal Woods and Waters " 102

Letters to the Editor:—

Acquired Characters. — Prof. E. Ray Lankester,

F.R.S 102

The Present Stale of Physiological Research. —

Prof. Francis Gotch, F.R.S 103

Wilde's Theory of the Secular Variation of Terrestrial

Magnetism.- L. A. Bauer 103

Boltzmann's .Minimum Theoicm. — Rev. H. W.

Watson, F.R.S. ; Edwd. P. Culverwell ... 105
The Alleged Absoluioness of Motions of Rotation. —
A. E. H. Love, F.R.S. ; Prof.'A. G. Greenhill,

F.R.S 105

Science Teaching in Schools.— O. Henrici ; H. G.

Wells ic6

The Explosion of a Mixture of Acetylene and Oxygen.

Dr. T. E. Thorpe, F.R.S lOO

"Newlhs Inorganic Chemistry."— G. S. Newth ;

M. M. Pattison Muir 106

Singing W-iter Pipes.— W. B. Croft 107

An Aurora on November 23. —J. Shaw ... 107

A .Snake "Playing 'Pussum.' L. C. Jones . . . 107

The Soaking of Seeds.— P. C. Glubb 107

History of Encke's Comet, liy W. T. Lynn . . loS
Progress of the Cataract Construction Company's

Works at Niagara 100

The Nile Reservoir no

Notes {IlliislraleJ.) '">

Our Astronomical Column :—

The Parallax of Nebula A 2241 1 14

A Possible New Zone of Asteroids 1 14

.\ New Comet . . ■ ' '4

A New Series of Nitrog:en Compounds 114

The Scientific Investigations of the Scottish

Fishery Board, liy W. G. . 115

Sir John Donnelly on Technical Education . 116

The Battle of the Forests. I. By Prof. B. E.

Fcrnow >">

Societies and Academies 119

Diary of Societies '20

Books, Pamphlets, and Serials Received 20

NA TURK

12 I

THURSDAY, DECEMBER 6, 1S94.

PECULIARITIES OF PSYCHICAL RESEARCH.
Apparitions and JhoKght Transference. By Frank
Podmore, M.A. (London : Walter Scott, 1894.)

MR. PODMORE, in the opening chapter of this
popular exposition of telepathy, pleads for the
recognition of psychical research by the general body of
scientific workers. He reminds us of the opposition
geological and biological discoveries have encountered,
and ventures to compare the circumstances of the small
group of investigators with which he is connected, and
more particularly the prejudice and derision they
encounter, with the experiences of Cuvier and Agassiz.
Convincing as this comparison may appear to the general
reader, in one respect at least it fails. Three hundred
years ago, all these phenomena of crystal gazing, thought
transference, and apparitions had a broader basis of
belief than they have to-day ; even a hundred years ago,
the ordinary scientific investigator was at little or no
advantage over the exponent of magic arts. But though,
as Mr. Podmore reminds us, the leading propositions of
natural science once encountered popular prejudice,
ridicule, contempt, hatred, far more abundantly than has
ever been the lot of psychical interpretations, they have
won through and triumphed, while the credit accorded
such evidence as the S.P.R. accumulates has, if any-
thing, diminished. A thing Mr. Podmore scarcely lays
sufficient stress upon is the fundamental difference in the
quality of the facts of " psychical research," as dis-
tinguished from those of scientific investigation — using
scientific in its stricter sense. It is true he has, with
an appearance of frankness, devoted a chapter to " special
grounds of caution," in which he concedes the truth of
various criticisms, and owns to several undeniable im-
postures ; but even here he passes from admissions to a
skilful argument in favour of telepathy, and avoids the
cardinal reason for keeping aloof from this field of
inquiry, that lies in the quality of the evidence.

The scientific advances of Cuvier and Agassiz, like all
true scientific discoveries, were based upon things that
could be perceived directly by themselves, and which
could be reproduced whenever required, and completely
examined under this condition and that, by those who
doubted the facts. That is the essential difference
between natural science and such a subject as history ;
science produces its facts, history at best produces
reputable witnesses to facts. Scientific men have never
attached much importance to unverifiable statements,
however eminent the source. If, to suppose an instance,
the greatest living anatomist were to announce that he had
dissected a dogfish and discovered lungs therein, adduce
his wife, a local general practitioner, two servants, and a
lady " named MissZ." in evidence, and add that he had
lost the specimen, there can be scarcely any doubt that,
in spite of his position and his character, the science of
anatomy would remain exactly where it was before his
discovery was proclaimed. But in this " psychical re-
search " the deliberate reproduction of phenomena under
conditions that admit of exhaustive sceptical examina-
tion appears to be generally impossible, and we are re-

NO. I3IO. VOL. 51]

peatedly asked to form opinions on the hearsay of Mr.
Podmore and his fellow-investigators.

This is not all. Few of the phenomena are directly
observed. Dr. Dee had his Kelly, Prof. Oliver J. Lodge
his Mrs. Piper. If Prof. Sedgwick would read the
thoughts of Prof. Oliver J. Lodge, or— as a phantasm of
the living— take to haunting some sceptical person, we
should have at least a statement at first hand, to doubt :
but as it is, these investigators manifest, as a rule,
no other mental phenomena than belief and repe-
tition. Reading through Mr. Podmore's book, the
student will be struck by the fact that the persons
who are in imm.ediate contact with the alleged pheno-
mena, the hireling eyes of the psychological in-
quirer, are persons usually youthful and coming from a
social level below that of the investigators. Take, for in-
stance, the Guthrie cases, to which Mr. Podmore attaches
considerable importance. Mr. Guthrie is a draper in
Liverpool, and by some means, not stated, he became
aware of psychic powers possessed by two of his em-
ployees— young ladies — whose identity is for some reason
veiled under the initials " E." and " R." These young
ladies were accordingly liberated at intervals from the
toils of shop or workroom, and made the subjects of
various experiments'; Mr. Guthrie, for instance, putting
cayenne pepper in his mouth, during a profound silence,
and Miss E. experiencing a taste of " mustard." Now
we must insist upon the fact, because it seriously affects
this question of evidence, that to a young lady following
the irksome and precarious calling of a drapers assistant,
the manifestation of psychic gifts opens up eminently
desirable possibilities and interests. Then, among other
of these intermediaries, we find "Jane"— a pitman's wife
— " Bertha J.," a peasant woman, hospital nurses and
out-patients, two men " who had been subjects of an
itinerant lecturer upon hypnotism," most of the letters
of the alphabet, several American M D.'s, lady medical
students, a baker's assistant, Mr. P., "a clerk in a whole-
sale house, aged nineteen, who possesses a good deal of
humour," and so forth.

Scarcely ever is the medium a person really inde-
pendent, in a financial sense, of the investigators who are
craving for pjienomena. It is necessary for us to believe
in the general good faith of this extremely dubious
material, or in the adequacy of the precautions against
fraud taken by persons whose scientific reputations are
now hopelessly bound up with the reality of the alleged
facts, before one can even begin to accept the experi-
mental basis upon which the theory of telepathy rests.
And this is the character of the investigations that Mr.
Podmore has compared with the work of Cuvier and
Agassiz : In no other field of inquiry is so much faith in
personal character and intelligence demanded, or so little
experimental verification possible. Indeed, the book is
oddly suggestive in places, with its use of initials and
second-hand guarantees of character, of the testimony
one finds adduced in favour of patent medicines.

Now, to the attentive reader of Mr. Podmore, the per-
suasion is unavoidable that the ordinary psychical in-
vestigator is endowed with a considerable facility of
belief, and is by no means instinct with the scientific
method. And this, where we are to take very much on
faith, is a material consideration. Anonymous statements

G

122

NATURE

[December 6, 1894

are accepted, and not only anonymous but self-contra-
dictory ones. Mrs. Piper hypnotised, personated a
French physician Dr. Phinuit, who did not know French,
and failed to give a satisfactory account of himself. Mrs.
riper, during her trance as Dr. Phinuit, gabbled,
made chance shots, " tished " for information, and was
generally a transparent enough imposition. Yet she
occasionally spoke of things she could not, according to
the investigators, have obtained a knowledge of by
ordinary means. For that they give her credit, and
forgive all her failures. Prof. Lodge, apparently eager to
believe, compares her utterances to the experience of
anyone listening at a telephone : " you hear the dim and
meaningless fragments of a city's gossip till back again
comes the voice obviously addressed to you, and speaking
w:th firmness and decision." Imagine in a real scientific
inquiry an investigator pursuing a theory through a com-
plicated series of observations, arbitrarily selecting those
that advance his views, and calling the others " dim and
meaningless until back comes the result obviously ad-
dressed to you : "

As one instance of the absence of scientific method
from these discussions, take M. Richet's and Mr.
Gumey's experiments with cards. In these experiments
an agent looked at the card, and a percipient guessed the
suit. M. Richet conducted 2927 trials, and 7S9 correct
guesses were made, the theory of probability only granting
732. The S.P.R. trials numbered 17.653, with 4760 suc-
cesses—347 in excess of the probable number. Now this is
adduced by Mr. Podmore as evidence for telepathy ; we
are asked to believe that about once in sixty times — that
is the excess above the probable ratio of successes — the
mental impression of the agent recorded itself upon the
brain of the percipient. Whether during the interval of
fifty-nine trials telepathy was in abeyance, Mr. Podmore
does not say, and the failure of the American S.P.R. to
confirm these results he sets aside because the details of
their experiments are not given— an excellent example to
the sceptic. Are we to believe that only once in sixty
times did the transferred thought surge up into con-
-ciousness, or that the transference occurs only at the
sixtieth time, or what ? A most obvious collateral test
seems to have been altogether overlooked, namely, for
someone to guess cards before the agent saw them, and
so to ascertain how far pure haphazard guessing of this
kind, or guessing on any particular gambler's " system,'
may fall away from the theory of probability. The de-
ductions of the theory of probability, be it remembered,
become certainties only when the number of cases is
mfinite. We have no grounds for assuming that in
seventeen thousand or seventy thousand, or in any finite
nvimber of cases, facts come into coincidence with this
theory. In an infinite number of sets of 17,653 trials we
might have every possible divergence from the average
result up to 17,653 successive failuresor 17,653 successive
successes. Taking a number of sets, they may be expected
to fluctuate round a mean result in agreement with the
theory of probability — that is all. These three sets of ex-
periments manifestly prove nothing. And this is how Mr.
Podmore prefaces his account of them : " In the follow-
ing cases, where the exact nature of the impression
received was not apparently classified by the percipient.
It may be presumed to have been either of a visual or
NO. I 3 10, VOL. 51]

an auditor)- nature.'' He begs the question, and in a
book addressed to the untrained mind of the general
reader 1 Nothing could show more clearly the tendency
of this psychical research to accept as evidence what is
really not evidence at all, its lack of critical capacity and
severe confirmatory inquiry, and the missionary spirit of
its exposition.

Enough has been said to show the essential difference
between "psychical " and scientific investigations, and
to justify the attitude of scepticism. After all, that
scepticism does nothing to hamper Mr. Podmore and his
associates from collecting their evidence, clarifying
their opinions, and building up such a defensible case as
their peculiar circumstances permit. And be it remem-
bered the scientific man of to-day occupies a responsible
position, that he possesses even a disproportionate share
of the public confidence, because of his reputation for
sceptical caution. The public mind is incapable of the
suspended judgment ; it will not stop at telepathy. Any
general recognition of the evidence of " psychical "
research will be taken by the outside public to mean the
recognition of ghosts, witchcraft, miracles, and the
pretensions of many a shabby-genteel Cagliostro, now
pining in a desert of incredulity, as undeniable f.icts.
Were Mr. Podmore's case strong — and it is singularly
weak — the undeniable possibility of a recrudescence of
superstition remains as a consideration against the un-
qualified recognition of his evidence.

H. G. Wells.

THE BEGINNINGS OF HISTORY.
The Dawn of Civilisation^Egypt and Chaldaa. By G.
Maspero. Edited by A. H. Siyce. Translated by
M. L. -McClure. (London : Society for Promoting
Christian Knowledge, 1S94.)

A S the winter season advances, and folk begin to
•^»- wend their way to Egypt, the enterprise of authors
and publishers keeps up a steady supply of good litera-
ture concerning the country which, since the English
occupation in 1SS2, has exercised upon people of all
nations a fascination which may be described as mar-
vellous. Only a few weeks ago an English translation of
Dr. Erman's Acgyptcn appeared, and already we have
before us a translation of a very important work by Prof.
Maspero in the same language. Hoth works are excel-
lent, but each is typical of the nationality of its writer,
and is really addressed to a different class of readers.
The work of Dr. Erman possesses a minuteness of detail
characteristic of the true German student, laborious and
accurate, while that of M. Maspero, though no less
accurate, discusses facts on a large scale with due refer-
ence to everything which bears upon them, and contains
generalisations which all thoughtful rea lers will accept
with gratitude ; added to this, we have the light and easy
style and logical arrangement of facts and sentences which
are the type of the work of the French master of his
subject. In short, Ur. Erman's book will form a standard
work of reference for the student of Egypt ; but that of
M. Maspero will take its place as a general history of
early oriental civilisation on the banks of the Nile,
Tigris, and Euphrates, and in the countries which lie
between.

December 6, 1894]

NATURE

123

The volume which we have in our hands, although it
is nowhere stated in it, seems to be the first of a series
which M. Maspero intends to devote to the history of the
ancient nations of the East ; and indeed the original
French work began to appear in weekly numbers with
the general title of Histoire Ancienne des Penples dc
rOrient some time ago. It is necessary to state this in
order that the reader may not confuse the new work of
M. Maspero with the small and older work, the first
edition of which appeared in Paris so far back as 1875,
for although both books run on the same lines, and have
the same aim, and the smaller originated the idea of the
larger, yet the scale of the new work has been so greatly
increased that it practically forms a new and indepen-
dent treatise on Oriental history and archaeology. The
first work ran through four editions at least, and was ex-
ceedingly popular ; but the new work, with its beautiful
illustrations, is intended to be in France what Rawlinson's
" Ancient Monarchies" was in England.

M. Maspero divides the first volume of his history
into two parts : the first treats of Egypt, and the second
of Ancient Chaldasa, six chapters being devoted to the
former subject, and three to the latter. A detailed de-
scription of the formation of Egypt as a land is folio wed
by an account of the Nile and of its influence upon the
history of the country and its people. The civilisation
of Egypt, according to M. Maspero, sprang up in the
country on the banks of the Nile, which was bounded
by Gebel Silsila on the south, Buto in the Delta on the
north, the mountain of Bakha on the east, and the
mountain of Manu on the west. The origin of the people
who produced it is difficult to trace, for the camp of
Egyptologists is divided in opinion on the matter. Many
scholars hold that the Egyptians came from Asia, but
not all who are of this opinion agree as to the route
followed by them into Egypt. Some would have them
enter Egypt by the Isthmus of Suez, and having gained
possession of the Delta, make their way up to Memphis,
Heliopolis, and further south ; others would have them
cross the Red Sea to Kosseir and so thence to Coptos,
and thus account partially for the traditions which made
Abydos in Upper Egypt the oldest city in Egypt ; and
again, others would make them cross over from the
Arabian Peninsula by the Straits of Bab el-Mandeb into
Africa, and skirting the Abyssinian mountains, enter
Egypt from the south. The first theory holds water so
long as we assume that the Egyptians made their way
from the East by the old trade routes into Egypt through
Syria ; in fact, this would be their only way if they set out
from countries on about the same parallel of latitude as
Babylon, for the want of water in the desert between the
Euphrates and Egypt has from time immemorial made
the route impossible even for the armies of mighty
kings, and every invasion of Egypt by peoples from
this region has been made by the way of northern
Syria. The second theory makes it necessary for the
emigrants from Asia to have crossed the waterless desert
in the Arabian Peninsula, and to have built boats suffi-
ciently large to cross the Red Sea ; this appears to be
the most improbable of all the theories yet put forth.
The third theory has much in its favour, for the passage
across the Straits of Bab el-Mandeb would be easy, and
the distance from shore to shore was probably less in
NO. I 3 10, VOL. 51]

those days than now. There exists yet another theory^
however, as to the Asiatic origin of the Egyptians. In a_
paper read at the Oriental Congress in 1892, Dr. Hommel
boldly asserted that the Egyptian civilisation was
derived from that of Babylon, and he attempted to prove
that the names of the gods of the one country were but
slightly modified forms of those of the others. Egypto-
logists have not, up to the present, accepted this theory.
A still more remarkable theory is that of Reinisch, who
believes that Asiatics, Europeans and Africans spring
from one family, whose original home was in the heart
of Africa, near the great equatorial lakes. M. Maspero
does not accept the theory of an Asiatic origin, but rather
believes that the Egyptian

"population presents the characteristics of those white
races which have been found established from all anti-
quity on the Mediterranean slope of the Libyan continent ;
this population is of African origin, and came to Egypt
from the west or south-west. In the valley, perhaps, it
may have met with a black race which it drove back or
destroyed ; and there, perhaps, too, it afterwards received
an accretion of Asiatic elements, introduced by way of
the isthmus and marshes of the Delta."

The caution with which M. Maspero puts forth this
theory shows that he has some doubts about it, and,
indeed, leaves the question exactly where it was. As to
the relationship between the Semitic languages and the
language of the hieroglyphics, he has no doubt that at one
time they all belonged to the same group ; the latter, how-
ever, separated from the former very early, "at a time when-
the vocabulary and the grammatical system of the group
had not as yet taken definite shape." This is an important
pronouncement for an Egyptologist to make, and although
it was said long ago by Semitic scholars, it is none the
less welcome since it comes from one of the first Egypt-
ologists of our times. Passing from the origin of the
people to their religion and manners and customs, M.
Maspero concisely and graphically describes their gods
and mythology, and the beliefs which swayed the minds
of the Egyptians for several thousands of years. The
size of M. Maspero's work and the limits of a brief article
absolutely preclude the possibility of noticing many rew
points in these subjects, which are admirably described,
and we rapidly pass from the account of the political
constitution of Egypt to the historical section of this
division of the book, which treats of the first fourteen.
dynasties.

The second part of the volume follows the plan of the
first, and sets out by describing the country, people,
gods, &c., of the ancient Chaldasans, or more properly
Babylonians, and the chapter which treats of their ideas
concerning the Creation is of considerable interest. In
this M. Maspero has rightly relied upon Jensen's epoch-
marking book, " Die Kosmologie der Babylonier," for
information, but it is to be regretted that Zimmern's
translations of the "Creation" and other tablets were not
published in time to be used by him. M. Maspero is,
however, the first to describe popularly the excellent
results achieved by Jensen in a subject which before he
treated it was truly chaos. Passing to historical times,
M. Maspero describes the foundation of the Babylonian
empire, basing all his statements upon a series of works
by Assyriological authorities, and cleverly harmonising

124

NATURE

[December 6, 1894

their various opinions. The chapter on the Chaldaean
civilisation is interesting, and is full of curious infor-
mation. The volume is concluded by an appendix treat-
ing of the Pharaohs of the Ancient and Middle Empires,
and by a useful index. M. Maspero is fortunate in
having found so careful a translator as Mrs. McClure,
who introduces her work in a preface which is at once
business-like and to the point. The editor's remarks
are, however, somewhat rambling, and in professing to
criticise M. Maspero's knowledge of matters Egyptian or
Babylonian, we think greatly out of place.

THE TRAXSMISSION OF POWER.
On the Dei'tlopment and Transmission of Power. By
William Cawthome Unwin, F.R.S. (London : Long-
mans, Green, and Co., 1S94.)

IT is well known that the author of this work has had
special opportunities for studying the subject of
transmission of power by all the various methods which
have, at different times, been adopted, and the engineering
world is to be congratulated on having received from his
pen a summary of the principles utilised in this class of
work, and of the possibilities of the future, as well as
very complete and authentic information about the
principal work that has been done In the past. This book
is ihe outcome of a course of " Howard' lectures de-
livered before the Society of Arts in 1893. It deals with
the generation, storage, and transmission or distribution
of power. The methods of transmission and distribution
Include water under pressure, compressed air, wire ropes,
steam, gas and electricity. The author recognises the
fact that transmission of power to distances has not been
so fully developed in the past as it is likely to be
shortly, and that the electrical transmission and distri-.
bution of power has more to claim in the way of promises
for the future than large achievements in the past.

The first chapters deal with the generation and the
cost of generating power by steam or hydraullcally.
One of the most valuable parts of the book is found in
those chapters where the economy of steam engines is
considered. These chapters deal with the losses in
boiler and engine In a very complete manner. The author
has realised very fully the fact that In any case of
generating power in large quantities, and distributing it
to small consumers, the cost of the horse power depends
largely upon the load curves at different times of the day,
and he draws attention to the very large excess of cost
per horse power of electric lighting stations over those
which are delivering power at a constant rate. Even in
a pumping station where the work is continuous, he finds
that about 35 per cent, more fuel is required than in a
careful trial, but in a station from which electric light or
power is distributed, the losses due to banking of boilers
and to engines working a portion of their time at an out-
put which is not economical, are such that the quantity
of fuel used per indicated horse power rises from \\ lbs.
per hour in a test trial with a condensing engine, to
3'3 lbs. under the special circumstances. The relative
advantages of the condensing and non-condensing
engines of the simple, compound, and triple expansion
engines, of the slcam-jacketing and superheating, are all
discussed admirably. Some pages also are devoted to
NO. I 3 10, VOL. 51]

the utilisation of house refuse as a fuel, and the Halpin
system of thermal storage receives some attention.

Some of the most important cases of utilising water
power are also discussed. It will surprise many readers
to find that even in 1876, 70,000-horse power was gene-
rated for manufacturing purposes from waterfalls in
Switzerland, and that in the United States in 1880,36
per cent, of the power used in manufacturing was water
power, and only 64 per cent, steam power.

Among the chapters devoted to transmission of power,
the most important, as pertaining more especially to the
author's experience, are those on hydraulic and com-
pressed air transmission. But in all branches of the
subject, not only are the general principles dealt with, but
there is to a pretty full extent a recapitulation of what
has already been done. The London Hydraulic Power
Company is taken as the best example of hydraulic
transmission, but Liverpool, Birmingham and Manchester
.ire also referred to, whilst most interesting accounts of
the hydraulic supply at Zurich and Geneva are given.
The principles of pneumatic distribution are very com-
pletely described, and the author has certainly made out
the case that when these principles are properly applied,
this system of distribution deserves more consideration
than is generally accorded to it. Naturally the Paris
distribution by this method is dealt with very fully, but
other examples of Interest are added. With regard to
the distribution of power by steam, the most important
case is that of New York, which Ur. Emery started In
1 88 1. Eight pages upon gas distribution for power
purposes are well worth some study, whether with regard
to manufactured gas, or the natural gas supply in Penn-
sylvania. Whilst compressed air receives the author's
attention to the extent of forty-eight pages, electrical
distribution is by no means so well favoured ; but the
author explains that, in the first place, it is not his own
speciality, and, in the second place, there are at the
present moment few cases of electrical transmission
combined with a complete system of distribution in a
town. A chapter is at the end devoted to the great
work which is now approaching its full development at
Niagara Falls.

This short review cannot pretend to give an adequate
Idea of the contents or value of Prof. Unwin s book.
Regarding the merits of the work generally, it is sufficient
to say, first, that throughout it is written with the utmost
fairness and impartiality ; and secondly, that if any
engineer were planning a system of transmission and
distribution of power in any special case, he would be
labouring under very considerable disadvantages if he had
not first consulted this latest and most complete work on
the development and transmission of power. G. F.

OUK BOOK SHELF.

A Treatise on Hygiene and Public Health. By Thomas
Stevenson, M.D., F.R.C.P., and Shirley F. Murphy.
(London : J. and A. Churchill, 1894.)

This volume is devoted to the subject of sanitary law,
and it well maintains the all-round excellence of the two
volumes that preceded it. Health officers will welcome
the appearance of such a lucid and comprehensive digest
of the law relating to the public health in England and
Wiiles, Ireland and Scotland.
iJuring comparatively recent years an immense amount

December 6, 1894]

NA TURE

'25

of piece-meal legislation bearing upon the public health
has been passed ; that much of this legislation, despite
subsequent amendments, still remains obscure and un-
satisfactory is clearly shown in the results of proceedings
undertaken by those whose duty it is to put it in force.
What cause to wonder, then, if the lay reader, by reason
of obscurities in the particular Act itself, or from the fact
that either amendments have been introduced by suc-
ceeding enactments or the particular Act is itself an
amendment of earlier statutes, becomesbewildered, and a
laudable desire to master an important subject is nipped
in the bud ? Those who are concerned in the adminis-
tration of this branch of the law have frequent occasions
to regret the lamentable ignorance existing among all
sections of the community as to their powers and
liabilities in matters which may seriously affect their
vital interests. Any simplification and consolidation,
therefore, more especially when it is undertaken, as in
this instance, by gentlemen of recognised legal ability,
should prove very welcome not only to health officers,
but also to the general public.

The decisions of the authors of the work to collate
the various provisions contained in different enactments
dealing with the same subject, and to present these — so
far as possible — freed of all legal phraserlogy, was a
happy one ; it makes the work unique in its service-
ability to the lay reader, who will gain from its perusal a
clearer and more definite knowledge of the public health
laws of the different parts of the United Kingdom than
he would succeed in doing — at a much greater sacrifice
of time and patience — from any other publication
dealing with the same subject.

Involution and E^'olution according to the Philosophy of
Cycles. By Kalpa. (London : Eyre and Spottiswoode,
1894.)
This is one of the books that most people would be glad
to lay aside, and, indeed, it is very difficult to say with
what object it has been written. The cycles decribed
have nothing to do with approximate commensurability
of planetary motions, and certainly not with evolu-
tion as understood in the modern acceptation of the
term. The author is a disciple of the school of Mdme.
Blavatsky, and draws his inspiration from that source,
tinged, it may be, with something of esoteric Buddhism,
and a good deal " spider-wove from his own brain." If
anyone wants to know what absurdities modern theo-
sophy is capable of, by all means let him read it, but
most people will be satisfied to take the contents at
second-hand. A very objectionable feature in the book
is the occasional cjuotation at the heads of chapters of
extracts from recognised writers of authority, conveying
the impression that the contents of the chapters following
are based upon modern science, and would meet the
approval of the authors from whom the quotations are
made. One illustration will be sufficient to show the
style of the author's reasoning and the character of the
information conveyed. The particular object is to de-
monstrate the birth of comets and worlds (p. 148). " But
the least subtilised type of those disembodied groups
does not take the same direction as the others. It keeps
going in orbits round the sun, shooting beams at him,
which, expelled (seemingly, at least), spread out behind
as a lengthy tail. Then, when the sun takes a short
rest, his brilliancy nearly spent, that entity moves olT,
its beams showing the way, but greatly reduced, and
of which nought remains ere the comet disappears for
parts unknown. It will be known to us as comet I."
We have, approximately, 200 pages of this sort of stuff,
paragraph after paragraph, all of which are utterly incom-
prehensible, and to wind up the whole we have sheet after
sheet of diagrams or illustrations which no man can
understand, and on which we should imagine the author
himself would pass a very doubtful examination.

NO. 1310, VOL. 5 l]

The Mountains of California. By John Muir. Pp. 381.

(London : T. Fisher Unwin, 1894.)
Few regions offer more remarkable subjects for the
student of nature than the State of California. There
are the two great mountain ranges — the Coast Range on
the west, and the .Sierra Nevada on the east. Great
canons furrow the latter to depths of from two
thousand to five thousand feet, and in the midtlle
of the deepest of them flourish the Sequoia,
the noble sugar and yellow pines, Douglas spruce,
Libocedrus, and the silver firs, each a giant of its
kind. Floods of lava cover the north half of the
High Sierra, and volcanic craters, recent and in all
stages of decay, are dotted over it. Mount Shasta is one
of these volcanic cones, rising to a height of more than
fourteen thousand feet above sea-level. Deep grooves flute
the sides of the mountains, and testify to glacial erosion.
It appears that so far south as latitude thirty-six degrees,
traces of glacial action abound. Mr. Muir has found sixty-
five residual glaciers in the portion of the Sierra
lying between latitudes thirty-six and thirty-nine
degrees. [The first one of these was discovered by
him in 1 871 between two of the peaks of the Merced
group. He also determined the rate of motion of
the middle of the Maclure glacier, near Mount Lyell,
to be but little more than an inch a day. Mount Shasta
has three glaciers ; while Mount Whitney, though the
highest mountain in the range, has none.

The special features of the volume are the descriptions
of the glaciers, glacier lakes, and glacier meadows in the
Californian mountains, and the interesting account of the
grand forest-trees of the Sierra.

LETTERS TO THE EDITOR.

\lhe Editor does not hold hiiiiulf resfonsible for opinions ex-
pressed by Ins correspondents. Neither can lie undertake
to return, or to correspond with the writers of, rejected
manuscripts intended for this or any other part of NATURE.
No notice is tahen of anonymous communications.]

Origin of Classes among the "Parasol" Ants.

Mr. T. H- Hart is Superintendent of the Royal Botanic
Gardens in Trinidad. He has sent me a copy of his report
pre.sented to the Legislative Council in March 1S93, and has
drawn my attention to certain facts contained in it concerning
the "Parasol" ants— the leaf-cutting ants which feed on the
fungi developed in masses of the cut leaves carried to their
nests. Both Mr. Bates and Mr. Belt described these ants ; but
described, it seems, different, though nearly allied, species, the
habits of which are partially unlike. As they are garden-pests,
Mr. Hart was led to examine into the development and social
arrangements of these ants ; establishing, to that end, arlificial
nests, after the manner adopted by Sir John Lubbock. Several
of the facts set down have an important bearing on a question
now under discussion. The following extracts, in which they
are named, I abridge by omitting passages not relevant to the
issue ; —

" The history of ray nesls is as follows: Numbers one and
two were both taken (.\ugust 9) on the same day, while de-
stroying nests in the Gardens, and were portions of separate nests
but of ihe same species. No. 3 was procured on September 5,
and is evidently a different although an allied species to Nos. I
and 2.

" Finding neither of my nests had a queen, I procured one
from another nest about to be destroyed, and placed it with No. I
nest. It was received by the workers, and at once attended
by a numerous relinue in royal slyle. On .Vusjust ,;o 1 removed
the queen from No. I and placed it with [So. 2, when it was
again received in a most loyal manner. . . .

"Ants taken from Nos. I and 2 and placed with No. 3 were
immediately destroyed by the latter, and even the solJiers of
No. 3, as well as workers or nurses, were destroyed when placed
with Nos. I and 2.

'■ In nest No. 2, from which I removed the queen on .\ugust
30, there are now in the pupa stage several queens and several

120

NATURE

[December 6, i 894

cules. The fomii of aot in nests Nos. i and 2 are as follows :
(a\ queen (i") mile (both wiogei, bj: the queen loses ils wings
after marital flight), (i' large workers, {d) small workers, and
(«) nurses. In nest No. 3 I have not yet seen the queen or
male, but it possesses — (j) so'.dier, {j>) larger workers, (.:)
smaller workers, and Kd) nurses ; but these are different in
foul to thise or niits No. I anl No. 2. Probably we might
add a third form of worker, as there are several sizes in the
nest. . . .

*' It is carious that in No. I nest, from which the queen was
removed on August 30, new q leens and males are now being
developed, while in No. 2 nest, where the queen is at present,
nothing but workers have been brought out, and if a queen larva
or pupa is placed there it is at once destroyed, while worker
larvae or pupse are amicably received. In No. 3 all the eggs,
larva;, and pupae collected with the nest have been hatched, and no
eg^ have since made their appearance to date. There is no
queen with this nest. ... On November 14 I attempted to
prove by experiment how small a number of 'parasol' ants it
required to form a new colony. I placed two dozen of ants (one
dozen workers and one dozen nurses) In two separate nests, No. 4
and No. 5. With No. 4 I placed a few larva: with a few rose petals
for them to manipulate. With No. 5 I gave a small piece of nest
covered with mycelium. Oa the i6th these nests were destroyed
by small foraging ants, known as the ' sugar ' or ' meat ' ant, and
I had to remove them and replace with a new colony. My
notes on these are not sufficiently lengthy to be of much impor-
tance. Bat I no'.ed four eggs laid on the l6:h, or two days after
being placjd in their new quarters ; no queen being present.
The experiment is bein^ continued. I may mention that in
No. 4 nest, in which no fungus was present, the larvae of all
sizes appeared to change into the pupae stage at once for want
o( food [a fact corresponding with the fact I have named as
observed by myself sixty years ago in the case of wasp larv.i;].
The circumstance tends to show that the development of the
insect is influenced entirely by the feeding it gets in the larvx
stage.

" In nest No. 2 before the introduction of a queen there were
no eggs or larv.-t. The first worker wa> hatched on October 27,
or fifty-seven days afterwards, and a continual succession ha>
since been maintained, but as yet (November 19) no males or
queens have made their appearance.'

In a lelter accompanying the report, Mr. Hart says : —

" Since the»e were published, my notes go to prove that ants
-can practically manufacture at will ; male, female, soldier,
worker, or nurse. Same of the workers are capable of laying
egg^, and from these can be produced all the various forms as well
as from a queen's egg.

" There does not, however, appear to be any difference in the
character of the food ; as I cannot find that the larger larva; are
fed with anything different to that given to the smaller."

These results were obtained before the recent discussion of the
<]ue«tion commenced, and as they agree with the results reached
by Grassi in the case of the TtrmiUi,-\\ can now scarcely be
doubted that the various forms or classes among the social injects
are wholly determined by the treatment of the larvae

S:. Leonards, December 2. IIkrbekt Spencer.

"Acquired Characters."

I DO not think we are in any way bound by the terms of
•the law enunciated by Limirck. Those laws m.iy be shown
to be erroneous in all but the suggestion of a principle which
may poisibly be developel into an important and far-reaching
doctrine, and if so the importance of the doctrine will be in no-
wise diminished by the crudity of the early .suggestion. There
is scarcely any scientific generalisation which does not require
an amended enunciation in each generation if it is to be in ac-
cordance with the contemporary state of knowledge. Neverthe-
less it seems to me that the second law of Lamarck does not
state thit a character acquired by individuals for Ihe first tiiiit is
inherited, or "alters the potential character of tile species."
Tne law stales tha'. nature preserves by generation what has been
acquired by individuals by the influence of the circumstances to
which their ra<c has been long exposed ; nut by the influence of
the circamstances lo which they alone have been exposed in their
own individual existences.

leaving Lamarck's laws and doctrines entirely out of the
■ juestion, if we dein; an acquired character as one which is
determined by the "operation on the Iniividual of given and

NO. 1310, VOL. 51]

related quantities of external agencies," I am not aware that
anyone has ever asserted that such a character is inherited. In
the sense of being completely reproduced in the offspring with-
out the operation of those external agencies. Bu; I think there
Is reason to believe that if the same quantity of external agency
acts on successive generations, it will produce more effect on
the second than on the first, or, to use more correct language,
that the effect in the second generation will be increased by a
potentiality derived from the dxA. It is argued that the very
possibility of the acquisition of new characters by the individnal
under new conditions is a proof that the old character had not
become fixed and congenital after the action of the old condition
on thousands of successive generations. But this is an illus-
tration of the difficulty of completely expressing the problem
in abstract language without reference to particular cases. If
I we consider the case of the pigmentation of the skin of the
I flounder, we find experimentally that exposure to light of the
1 lower side for some years produces some pigmentation, but not
so much as that on the upper side exposed in the individual for
I the same time. The action on the two sides in the individual
being thus equal, or even greater on the lower side, how are we
lo account for the difference in favour of the upper? Evidently
the congenital potentiality of the two sides is different. The
old character has then become fixed and congenital to a certain
very important degree. If no efl'ect were produced by the
action of light on the lo.ver side of the individual, there would
be no evidence that the congenital difference in the two sides
had been produced by the difference in the relation to light
repealed in countless successive generations. O.i ihe other
hand. If the equal exposure of both sides produced equal pig-
mentation in the same time, this would be evidence that the
difference in the pigmentation under normal conditions was not
a congenital character at all. But as the facts stand, the only
conclusion which is in accordance with them is that the con-
genital difference between the two sides is due to the gradual
accumulation of slight effects on the congenital potentiality of
the germ consequent upon th; action of light in the individual,
I could mention many other similar instances, which I think do
constitute a reason for " assocLating the s imewhat superficial
and late responses of the parts of a growing individual to normal
or abnormal forces of its environment with that more subtle
and profound disturbance which Is permanent and affects the
potential char.icter of the germ."

I am far, however, from supposing that all specific, generic,
or morphological characters are due to the direct action of the
environment in the somi, and equally far from admitting that
every one of these characters has a part to pl.iy in the struggle
for existence. J. T. Cr.NNiNt".HAM.

Plymouth, November 30.

The distinction between the "acquired characters" of
Lamarck and the other " responsive characters " which follow
the " influence of the normal environment " Is, I venture to
think, not very important. The two kinds of characters are
indeed admitted by Prof. Linkestcr to be "of the same order,"
and their cssentLal unity is clearly sho.vn when we attempt to
trace the history of evolution as Limirck conceived it.

'X\\t first Increase in length of the neck of the giralTe or swan
was no doubt, according lo Lamarck, "an acquisition under
ticu conditions of iic-v character." Hut when the process had
started, its subsequent sl.iges could hardly be spoken of in this
way. The effort of stretching, which was supposed to supply
the condition for further increase, was then neither "new " nor
" special and abnormal."

In the numerous discussions of the last seven years the term

" acquired" has b;en employed to cover both classes of charac-

' lers, and, indeed, the argument has chiefly turned 011 the effect

I of normal rather than abnormal and special conditions, bec.iuse

' the evidence supplied by the former for or against hereditary

transmission was so much more convincing than that supplied

by the latter.

Although the term " acquired " is an unfortunate one, and
has added many difficulties and obscurilies which would have
been avoided by the substitution of Prof. Lankesler's term,
" responsive, ' 1 think it would only increase the difficulties
if it were now authoritatively maintained that, although the
majority of instances discussed and the really crucial cases ad-
duced are "of the same order" as .acquired characters, they
must no longer be called by this name.

I entirely agree with Prof. Lankestcr as to the mutual anta-

December 6, 1894J

NA TURE

gonism between the two laws of Lamarck. The first law assumes
that a past history of indefinite duration is powerless to create a
bias by which the present can be controlled ; while the second
assumes that the brief history of the present can readily raise a
bias to control the future. Edward B. Poulton.

Oxford, December 2.

The Homing of Limpets.

In Nature, vol. xxxi. p. 200, Prof. .-Vinsworth Davis de-
scribes some observations he had made on the habits of the
limpet. Marked individuals were found to return from their
excursions, extending to a distance of some three feet, and to
settle down on the spot which is their permanent home. By
exci-ion of the tentacles in two individuals Prof. Davis was led
to conclude that it is not by these organs that the limpet finds
its way back to its own particular scar. "The sense of smell
then suggested itself, and it occurred to me," writes Prof.
Davis, "that one reason why limpets kept on their scars when
covered by the water was lo prevent the scent being washed
oflf. With a view to determine this, the space between a
wandering limpet and its scar and the scar was carefully washed
again and again with sea-water. In spite of this, the limpet in
question readily found its way back again."

Last summer I had some opportunities of making observa-
tions at Mewps Bay, near Lulworlh, in Dorsetshire. I trust
that Prof. Davis will not consider a brief record of the results ot
these observations a case of unsportsmanlike poacning on his
preserves.

The method I adopted was to remove the limpets from the
rock and affix them at various distances from their scars. This
can be done without difficulty or injury if one catches them as
they are moving. But one must make sure that they are iust
leaving or returning to their own proper homes, and are not
taken in the midst of a more extended peregrination, as in that
case their special scars cannot be noted. Failure to be
careful in this matter vitiated my earlier observations, which
are therefore excluded in the following table : —

No.

Distance

No. returnod.

removed.

in inche-;.

In 2 tides. In 4 tides. L

25

6

21 ... — ...

21

12

13 ... s ...

21

18

10 ... 6

36

24 ..

I ... I

From the nature of the strata the removal to a distance of
12 inches or more generally involved taking the limpets over a
corner of rock.

In most cases the individuals which failed to return :o their
respective scars look up new positions. In several cases when
they were removed to a distance of a few inches from this new
position they returned to it. In one case where the limpet had
taken up such a new position it returned thereto after having
been removed to its original scar.

Observation of the limpets without such experimental re-
moval shows that they make their excursions in search of food
chiefly as the tide leaves them and when it is returning. They
generally seem to get back to the scar before the tide has well
covered it. I have watched them return over considerable dis-
tances. In one case ten inches, over a somewhat curved
course, was covered in a little under twenty minutes. In
another case the limpet on its return journey had to pass
between two other limpets, which necessitated the lifting of the
shell to some height so as to pass over one of these. On reach-
ing their scar they twist and turn about so as to fit down.
When they come wrong way round they rotate pretty rapidly
through the iSo° to get into position. The final position on
the scar is a constant one. One was observed to make a short
excursion from and to return lo its scar under stillish water.
As a rule they seem to remain fixed under water.

The greatest distance I have watched a limpet reach from its
scar was 22 inches. But I have found limpets at a distance of
3 feet from their scars — that is to say, from scars on to which
they fitted perfectly. This was on a large fiat surface.

When they move, the tentacles are projected out beyond the
shell, and keep on touching and slightly adhering to the rock.
On reaching the scar they carefully feel round it with the tent-
acles. I am disposed to question the results of Prof. Davis's
experiments on the removal of the tentacles. But further

NO.

I3IO, VOL. 51]

observations and experiments are needed to settle the point.
I understand that Prof. Davis is now at work upon the subject.
.\n injury to the edge of the shell seems to be repaired with
whitish shell-material in the course of about ten days. And
when a new position is taken up to which the shape of the shell
is not suited, there appears lo be a tendency for the shell to
accommodate itself to the uneven surface of new growth along
the edges. But this again is a matter on which further obser-
vation and experiment are required.

C. Lloyd Morgan.

Gravitation.

The nature of my suggestion {vide Nature November 15,
p. 57) is simply this: — A phenomenon of adhesion between
solids immersed in a tensile liquid presents itself. The explana-
tion ofi'ered (as I understand it) suggests that whether the bodies
are attracted at long or short distances, will be a question
entirely of the extension in the stressed medium of the modified
layer. If this explanation be a correct one, or if any explana-
tion involving a reaction between a modified layer (whether
condensed or rarefied) and a tensile liquid will account for the
phenomenon, then I say the experiment is a suggestive one as
regards gravitation.

How far the modified layer will extend depends upon the l.iw
according to which the stress is distributed in the medium. In
the case of matter acting upon matter at molecular distances we
have reason to believe that the decrement of the stress is a rapid
one. We possess no such knowledge when matter and ether
alone are involved, and until we know how a modification of
the ether around matter would display itself to our observation,
I do not think the possibility of a remotely extended modifica-
tion can be denied. Gravitation might be the sole resultant
phenomenon affecting our senses. J. Joly.

Trinity College, Dublin.

The Ratio of the Specific Heats of Gases.

I REMEMBER that in the discussion of eighteen years ago it
was understood that you could get I '4 for the ratio, if the-
molecules had each five degrees ol freedom only— if they were,
for instance, perfectly smooth, elastic spheroids. Probably the
ultimate source of our knowledge in this respect was Boltzmann'-.^
paper, to which Mr. Bryan refers us. The difficulty at the time-
seemed to be mainly one of faith. One could not believe that
the molecules were solid elastic bodies, however useful the dis.
cussion of such bodies might be in defining a limiting case. As.
the white posts along a road are put to show you where yon
should not go, not where you should go. It was further sup-
posed, perhaps without sufficient reason, that the phenomena
of the spectroscope required us to attribute many degrees of
freedom to the molecules.

I hope Mr. Bryan will, as I have no doubt he can, develop-
his theory that all these phenomena can be accounted for by:
the electromagnetic theory of light, without attributing to thir
molecules more than five degrees of freedom. We have to ex-
plain, as it seems to me, how the ether will assume ditTerent sel-^
of vibrations according to the shape of the bodies in contact
with it. S. H. BURBURY.

I New Square, Lincoln's Inn.

An Observation on Moths.

I THINK Dr. L. C. Jones (No. 130S, p. 79) has missed the-
true reason of the unexpanding wings of his moths liberateil
from the pupa-case before the struggles of the inmate had splii
the skin, and freed them in the ordinary course.

What was missing to them was the pressure in the act of
emergence, which at one and the same time expels a discharge
of superfluous humours from the abdomen, and forces the vital
fluids through the folded and crumpled wings. Special extra
provision is made for this, in the flask-shaped cocoons ol
Saturnia Pavania- minor, for example, and if the pupa be
taken out of this, and allowed to emerge at full matuiity, it is
always an abortion with heavy, overloaded abdomen, and
wings that never expand. Every collector, also, who has bred
the earth-burying sphinxes — Sphinx Liguslri, for example —
knows how often they emerge in this condition, either through
not being supplied with soil of the needful tenacity, or from the
difficulty of keeping it of the natural degree of moisture.

I 28

NA TURE

[December 6, 1894

It woold be rash to assume that the straggles of parturition
have no analogous bearing on the after vigour and welfare of
offspring in the mammalid also. Henry Cecii-.

Bregner, Bournemouth, November 27.

Snakes "Playing 'Possum."

In connection with Dr. L. C. Jones' account last week of
•.he Puffing Adder that feigned death, it may be of interest to
note that on several occasions I have observed similar behaviour
on the part of the English grass-snake {Coluber iiatrix). On
finding escape impossible the animal would roll slightly over,
with its mouth open to its widest extent, and its tongue pro-
truded, and remain perfectly limp and flaccid, allowing itself to
be stroked, moved, and even carried in the hand with the head
and tail dangling down on opposite side.«, without showing any
signs of animation. So sudden is the change from activity to
quiescence, and so admirable the imitation of lifelessness that

VOLCANIC STALACTITES.

\ CURIOUS formation is described by Mr. E. Gold-
■'^ smith in the Proceeiiings of the Philadelphia
Academy of Natural Sciences (parti. 1S94, p. 107). It
is well known that the highly heated and very tluid lava
in the Kilauea crater at Hawaii, as well as in other
craters, is occasionally shot up into the air some thirty
feet or more. This lava in its descent through the air
becomes very porous. If such a highly porous rock have
a space underneath, a fresh deposit of liquid lava will
trickle through the porous cooled lava, forming as it
solidifies the pendant stalactites shown in the accom-
panying picture, which illustrates Mr. (Goldsmith's paper,
and has been kindly sent to us by the Academy.
The figure represents the entrance to a volcanic cave,
photographed by Profs. Sharp and Libbey. It shows an
overhanging roof of porous basalt, from which are sus-

Flr,, t. — Volcanic Stalactites and .Stalagmites.

It pif scnf-, lliat on the lirst cccation on which 1 witnessed it
(now many years ago), I tclievcd the snake to have been seized
by some tpccics of fit, and to be at the point of death until, in
the laint hope of alleviating its seemingly dcspeialc condition,
I plunged It into some cold water, with the happy lesult of
efTecling its immediate ictloralion, ihc snake possibly thinking
its ruic had been successful, and it was once moie free. I have
known case;, however, in which Ihe symptoms have persisted
ifter the application of the cold-water cure. Sul>sci|uently I
disco\eicd that no lieaimcnt of any kind was nccessaiy, as the
make would "come to" of its own accoid after a while.

A point which I should be very inlercslid to Icain is whether
this condition is produced voluntarily by the animal for protec-
tive purposes, "the fan.e with intent to deceive," or is the
result ol a gcrcral nei«ous inhibition, produced icflcxly by Ihc
a. tion of fright, which would tender it mote or less analogous
10 a fainting fit. G. IC. Hauow.

NO. 1310. VOL. 51]

pended irregularly gnarled rods of volcanic stalactites «
on the floor are scattered fantastic-shaped volcanic
stalagmites, which seem to be much thicker than the
pendant rods above. Mr. Goldsmith says that the
stalactites are about one-lourlh o( an inch thick, and
about eight inches long. They show no disposition to
form cones like those seen in limestone caves. They
are mostly hollow and porous, and very brittle. The
colour is usually a deep black, but sometimes a part is of
a brownish tint, due, Mr. Goldsmith thinks, to a higher
oxidation of the magnetite present. Fragments of the
stalactites, when microscopically examined, exhibited a
glasfy felspar having apparently the characteristic of
sanidine. Magnetite occurred in great profusion, and
also gases, probably air. Augite was suspected, but not
definitely determined. The specific gravity of a coarse

December 6, 1894I

NA TURE

I 29

powder produced from the stalactites was found to be
2"85. The lava is decidedly basic, as the quantity of
silica determined analytically was 4S'5J per cent. On
some of the stalactites a thin layer of colourless crystals
were recognised under the microscope. An examination
of these incrusting crystals proved them to be selenite.

NOTES.

We are pleased to note Ihat the Court of the Salters' Com-
pany have placed at the disposal of the City and Guilds of London
Institute a grant of £,iyi a year, for founding one or more
Fellowships for the encouragement of higher research in
chemistry in its relation to manufactures. The Fellowships
will be awarded by the E.'ieciitive Committee of the Institute,
and the amount of the grant attached to each will be determined
by the Committee, with reference to the nature of the research,
the time required to complete it, and the merits of the candidate.
The Executive Committee will each year apply the sum pro-
vided by the .Salters' Company to the award of Fellowships to
British-born subjects, of a value not exceeding ;^I50 (a) to
students of the Institute who have completed a full three-years'
course of instruction in the chemical department of the
Central Technical College, or (/') to candidates duly qualified
in the methods of chemical research in its relation to manu-
factures, without restriction as to age or place of previous
study. A Fellowship may be renewed for a second and third
year, but cannot be held by anyone for more than three years.
The holders of the Fellowships will be required to devote their
whole time to the prosecution of research, unless otherwise
sanctioned by the Executive Committee. The researches will
be carried out at the Institute's Central Technical College. Ap-
plications for Fellowships should be made in writing addressed
to the Honorary Secretary of [the Institute, Gresham College,
Basinghall Street, London, E.C., and should state the nature
of the research proposed to be undertaken, and the qualifications
of the candidate. The first award will be made early in the
new year.

We notice with deep regret that Sir Charles T. Newton,
K.C.B., the eminent archceologist, died on November 28.

Communication by telephone between Vienna and Berlin
has just been opened. The length of the line is 410 miles.

Dr. S. Nawaschin has been appointed Professor of Botany
and Director of the Botanic Garden at the University of Kiew ;
and Dr. IC. Schilbersky Professor of Botany and Vegetable
Pathology at the Hungarian Agricultural Institute, Buda-Pesth.

The editorship oixhejahrhiklurjurwiiscnschajllkhe Botanik,
vacant by the death of Dr. I'riiigsheim, has been accepted by
Prof. Pfeffer, of Leipzig, and Prof. Strasburger, of Bonn. All
communications should be addressed to the former of these.
The /(i/(;-('w/;«- have been edited by Dr. Pringsheim since their
commencement in 1857, and contain many important contri-
butions to structural and physiological botany.

Dr. Philip Lenard, who was the late Prof. Hertz's
assistant and prival-docent at the University of Bonn, has
recently been appointed Extraordinary Professor of Physics in
the University of Breslau. He has published a number of im-
portant investigations on cathode rays, phosphorescence,
electrification of water-drops, and kindred subjects.

The Council of the British Institute of Public Health,
realising the great and general interest which is at the present
time taken in the question of the anti-toxic serum treatment
of diphtheria, have made arrangements for a lecture to be
given in the Examination Hall of the Rjyal Colleges of

NO. 1310. VOL. 5 1]

Physicians and Surgeons, Victoria Embankment, on Friday,
December 7, at 5 p.m. by Dr. G. Sims Woodhead, entitled
"The Diagnosis and .\nti-toxic Treatment of Diphtheria. "

The second series of lectures fgiven by the Sunday Lecture
Society begins on Sunday afternoon, December '9, in St,
George's Hall, Langham Place, at 4 p.m., when Mr. E,
Neville Rolfe will lecture on " The Buried Cities of
Campania." Lectures will be subsequently given by Mr.
Wyke Bayliss, Prof. Marshall Ward, F.R.S., Prof Vivian B.
Lewes, Mr. Oswald Brown, Mr. .\tthur Clayden, and Mr. Jas,
Craven.

The following lecture arrangements have been made at the
Royal Institution : Prof. J. A. Fleming, F. R. S., six lectures
(adapted to a juvenile auditory) on the work of an electric
current ; Prof Charles Stewart, twelve lectures on the internal
framework of plants and animals ; Mr. L. Fletcher, F.R.S., three
lectures on meteorites; Dr. E. B. Tylor, F. R. S., two lectures
on animism ; Lord Rayleigh will also deliver six lectures.
The Friday evening meetings will commence on January iS,
when Prof. Dewar will deliver a discourse on phosphores-
cence and photographic action at the temperature of boiling
liquid air. Succeeding discourses will probably be given by
Sir Colin Scott-Moncrieff, Dr. G. Sims Woodhead, Mr. Clin-
ton T. Dent, Prof A. Schuster, Prof. A. W. Rucker, Prof.
Roberts-Austen, Prof. H. E, Armstrong, and Lord Rayleigh,
among others.

Dr. Patterson, in a lecture before the Piscatorial Society,
at the Holborn Restaurant this week, entitled " Salmon, Sea-
trout, and Trout— What are they ? " maintained that they were
all varieties of one species, varying according to their environ-
ments. On the same evening an exhibition of this year's speci-
men fish was held by this Society in their museum at the Holborn.

At a meeting held at the Borough Road Polytechnic, on
November 23, a London branch of the Conchological Society of
Great Britain and Ireland was formed. -It is thought that such
a branch, with monthly meetings for discussion, for exhibition,
and for exchange, cannot fail to be of advantage. The branch
will in no way be a rival of the Malacological Society, but
probably a feeder to it. The first ordinary meeting will be held
on Thursday, January lo, 1895, at 7 p.m., in a room lent by
the Governors of the Borough lioad Polytechnic. The attend-
ance of any conchologists in or near London will be welcomed
at this meeting.

During the past few years the American Museum of Natural
History, situated in Central Park, New York City, has grown
very considerably. It suffers from the common complaint, how-
ever, of not having suflicient funds to devote to the enlargement
of the collections, and this in a city where millionaires most do
congregate. The report of the operations of the Institution last
year shows that the opening of the museum on Sundays is greatly
appreciated. Many important additions have been made to the
various collections, the most noteworthy accessions being in the
department of mammalian palasontology. .\lthough only in
the third year of its establishment, the collections in this depart-
ment already equal in importance those secured by other
institutions through many years of eflfort. The intention is to
form a great collection to represent the evolution of the mam-
mals of North America. Thus far the expeditions to the
Rocky Mountain region have secured nearly one thousand five
hundred specimens. Fifteen perfect skulls have been obtained
from the Bridger Uasin, Wyoming. The remains of monkeys,
horses, tapirs, primitive rhinoceroses and rodents have also
been obtained by the explorations under Dr. J. L. Wortman,
and many of them are in an excellent state of preservation.
The most notable specimen in the collection is a complete

l.iO

A'A TURE

[December 6, 1S94

skeleton of a large Carnivore of the size of a tiger, and is said
to. be the most perfect specimen of the kind ever found. The
total number of volumes in the library now exceeds twenty-
eight thousand. We sincerely hope that the citizens of New
York will see that the usefulness of the Institution is not
limited by the lack of means to acquire new and important
material, and to provide proper accommodation for it. They
must surely recognise thai, even from a commercial point of
view, the museum is of the highest value.

In connection with our note last week, on the wreck of the
Falcon, the steamer of the Peary expedition, and the loss of all
on board, it ought to have been stated that the vessel, after
landing the returning members of Mr. Peary's party, had sailed
from St. John's with a cargo of coal, and that none of the ex-
ploring party, whose charter of the vessel terminated on their
landing, were on board.

In the Geo^rafhical yournal for December, Captain Mockler
Ferryman describes and illustrates the glacier lake known as the
Dxmme Vand, near the Hardanger Fiord, in Norway. The
Rembesdal glacier at the head of the Simodal, stretches across
and dams up a lateral valley in which the lake in question
is formed. When during summer the ice-barrier gives way, as
it occasionally does, floods of the most disastrous kind are pro-
duced in the Simodal. The Norwegian Government has deter-
mined to construct a tunnel through the rocks at the mouth of
the lateral valley, through which the surplus water of the
Dxmme Vand may be harmlessly drained when the level rises
to a dangerous height.

Chemical laboratories can now dispense with the wasteful
and unpleasant installation for generating sulphuretted hydro-
gen, for we learn from Indintrics and Iron that liquid sulphur-
etted hydrogen is commercially obtainable. Although this gas is
easily liquefied, the difficulties of manufacture in large quantities
at an economic rate have prevented its introduction as a labora-
tory reagent. Messrs. Baird and Tatlock, who are the sole
agents for this commodity, supply the liquid compressed into
specially-prepared steel cylinders, each containing one pound of
liquid, equal to about eleven cubic feet of gas at atmospheric
pressure. Larger cylinders can also be had. In this compressed
form, the gas has the advant.ige of being cleanly and always
ready for use, and in those laboratories in which it is only
occasionally required as a reagent, a cylinder ought to be in-
cluded in the laboratory stock. Our contemporary announces
that the same firm is about to place liquid chlorine and ethylene
on the market.

For collections of Coleopterous, Lepidopterous and other
insects, the nature of the pin for fastening the specimens is a
question of great importance. Ordinary pins of brass, even
though well tinned, frequently oxidise in the body of the
insect, and eventually destroy the specimen. Black varnished
pins are almost as bad, for the varnish soon cracks, leaving the
metal exposed. Even plated pins do not appear to resist the
action of the compound) developed in the bjdy of the insect,
though solid silver ones will. Ur. II. G. Knaggs introduced a
bronze pin which has found favour among many entomologists ;
nevertheless, it i« far from being a perfect fastener. In the
December number of the Iintoiiiolof^i>l' > Moiilkly Magazine, he
direct-- attention to a pin made from a nickel alloy by Mesirs.
Deyrolle, of Paris. This pin posjoscs great advantages over
those generally used, and of which the metal basis is brass. It
will probably be widely used by collectors, for its price need
only be a little higher than that of an ordinary pin.

That the efTiciency of acoustic fog-signals for purposes of
navigation is a< yet very doubtful, may be seen from a dis-
cusiion appearing in llama. There are many peculiarities in

NO. 1310, VOL. 51]

the behaviour of sound, propagated over the surface of the sea
from the coast, which require further scientific investigation.
Mr. Arnold B. Johnson, author of "The Modern Lighthouse
Service," gives it as a general rule, that in proceeding from the
neighbourhood of the fog-signal apparatus out into the sea for
about two miles a zone is entered in which the signal becomes
inaudible. This zone has a width varying from one mile to a
mile and a half. That this phenomenon is not confined to
coast stations is evident from the fact that it was observed in
the case of a station situated on a rock twenty miles from the
nearest land. Several such zones are often produced when a
steep cliff lies at the back of the signal station. The observa-
tions made on the coast of New England are fully borne out by
those made at the mouths of the Elbe and Weser. .Vmong the
pilots of the German coast it is well known that the sound
rockets fired on Heligoland are heard at distances sometimes
exceeding twenty miles, become inaudible on approaching the
island, and reappear in the immediate neighbourhood of the
island. An altogether unexplained and apparently undiscussed
phenomenon is that noticed in a specially marked manner in
the fog-horn of the Weser lightship. When the sound com-
mences it appears to proceed from a direction entirely different
from that in which it dies away.

A SERIES of Bulletins of the Madras Government Museum
has been commenced by the superintendent, Mr. Edgar
Thurston ; and parts i. and ii., which have reached this country,
contain much useful information upon the fisheries and marine
zoology of the Presidency. Part i. contains a revised account
of the superintendent's "Notes on the Pearl and Cliank
Fisheries of the Gulf of Manaar," and its subject matter is
already known in great part to British students of "applied
zoology." Part, ii., entitled " Note on Tours along the Mala-
bar Coast," records a number of interesting observations in
marine zoology made on the west coast of Madras. It is in-
structive to note that even there the natives have their fishery
question. It is stated that formerly the sardines of the co.ast
always arrived reguKirly, and remained throughout the season ;
and the fishermen's belief is that they are at the present d.ay
frightened away by the numerous steamers which call at Cochin,
and retire in search of a less disturbed spot. In addition to
steamboat tralVic ; noises in boats, ringing church bells, artillery
practice, the erection of lighthouses, gutting fish at sea, using
fish as manure, burning kelp, and the wickedness of the people,
have been charged with being responsible for a falling of! of the
fish supply ; but, as Mr. C. E. Fryer has naively remarked,
"of these alleged causes only the last, it is to be feared, has
been, and is likely to be, a permanent f.actor in the case."

We have received from the Rev. S. Chevalier, the second
repoit of the Shanghai Meteorological Society. This number
is entirely devoted to a notice of the typhoons of the year 1S93,
and a final chapter on the general tracks of the typhoons in the
Chinese seas. The discussion of each storm is accompanied by
diagrams showing the position of the centre at various dates ;
several examples reportetl in the present work .show that the
bearing of the centre coincides with the direction of the swell
of the sea, but further observations on that special point are
required. The tracks of the typhoons have been cl.ossed (I)
according to the times of their occurrence, and (2) according to
the countries which they visit. The first month of the typhoon
season is May, but the storms are of rare occurrence before
July ; it is noticeable that they originate in dilTerenl positions,
and take somewhat different routes In illflerent months. From
the middle of September the typhojns do not reach .Shanghai,
but they occur further south for some months later. In dividing
them according to localities. Father Chevalier distinguishes
three classes, viz. Japan typhoons, China, and Cochiu China
t yphoons.

December 6, 1894]

MATURE

131

The Report of the Botanical Exchange Club of the British
Isles for 1893, just received, contains a number of useful and
interesting notes on critical and rare British species, the general
Kiiliiis, Hittacium, and Polamogitoii coming in for a specially
Urge share of attention. It is edited by Mr Jas. Groves.

The results of the meteorological observations made at the
United States Naval Observatory during 18S9, and the mag-
netic observations made at the same observatory during 1892,
have just reached us. It would be to the advantage of science
if the observations could be published without such a long
delay.

The twenty-first annual report of the Geological and
Natural History Survey of Minnesota has been received. It
embraces statements relating to progress in the strictly
geological portion of the Survey. Independent reports will be
published upon the botanical and zoological departments of the
work.

The December number of the Geological Magazine contains
an account of the life and work of the late Mr. William
Topley, F. R. S. , written by Mr. H. B. Woodward, and
accompanied by a portrait of the deceased geologist. The
memoir is a tribute to a life of unremitting labour in .he cause
of geology, and an expression of the high regard in which
Mr. Topley is held by all who cherish his memory.

The Geographical Journal this month gives prominence to a
new feature in the way of short summaries of the most recent
and trustworthy literature on parts of the world where public
interest is concentrated for the time. The regions dealt with
are the Waziri country and Madagascar, and in addition there
are two special papers of considerable length on Eastern Asia
— one by Mr. A. R. Agassiz, on the commercial resources of
Manchuria ; the other by Baron von Richthofen, on China,
Japan, and Korea.

Hitherto Brehm's well-known collection of works on
natural history, in the Merveilles de ia Naiure series, published
by MM. J. B. Bailliereet Fils, Paris, has not comprised a volume
on botany. This gap is now, however, to be filled by " Le
Monde des Plantes," of which the first part has just appeared.
The author of the work is Prof. Paul Constantin. There will
be eight fasciculi altogether. When the work is completed
its two volumes will run into fifteen hundred pages, and be
embellished by two thousand illustrations. Particular attention
is paid to the use of plants for food, and in medicine, industries,
agriculture, and horticulture. The biological characters are
also carefully treated. The work promises to be the best
popular botanical work published in France, and therefore
6ttingly finds a place in Brehm's series on the wonders of nature.

Mr. a. S. Ghosh has sent us a slender little pamphlet on
"Pedal and Antipedal Triangles," being an attempt to in-
vestigate the laws of their evolution. (Calcutta : Patrick Press,
1894.) The primitive triangle is considered as obtained from
the pedal triangle, and is called its antipedal triangle ; so that
what is sometimes called the excentric triangle is the antipedal
of the primitive triangle. The whole of the pamphlet, which
is a fairly neat piece of work, is merely a solution in cxtemo of
a "ten-minute conundrum."

We have received the Proceedings and Transactions of the
Royal Society of Canada, for the year 1892 (vol. x.). The
volume contains six papers in the section of mathematical, physi-
cal, and chemical sciences. Among these we notice one on the
Mexican type in the crystallisation of the topaz, and another
11 'jbseivations of sun-spots at the McGill College Observatory.

lie section of geological and biological sciences contains the
presidential address on the diffusion and sequence of the Cam-
brian faunas ; and, among others, papers on the artificial propa-

NO. 1310, \OL. 51]

gation of marine food fishes and edible crustaceans, and on the
correlation of early cretaceous floras in Canada and the United
St ites.

At the inaugural meeting of the fourteenth session of the
Institution of Junior Engineers, held on November 16, Mr.
Alexander Siemens gave some wholesome advice to young
engineers and inventors. In the course of his address, he
dispelled the fable about the circumstances which led to the in-
vention of the steam engine. According to the popular version.
Watt, as a small boy, saw the lid of a tea-kettle move up and
down, when the water was boiling, and this suggested to him
the construction of the steam engine. As a matter of fact.
Watt made himself acquainted with what had been done before
(a point altogether ignored in the popular version), and had to
work verj' hard before he brought his invention to a successful
issue. His example is typical of the true method of progress,
and it may be said generally, that in order to approach a
problem with the best prospect of success, it is necessary (l) to
define, as accurately as possible, the want that exists, or the par-
ticular object that is to be attained ; (2) to be well acquainted with
the scientific principles which come into play ; (3) to know how
the want is met, or the'object attained in practical life ; (4) to
find out what proposals have been made by others in the same
or in a similar case. A careful attention to these re-
quirements will prevent much disappointment and waste of
energy. The records of the Patent Office show that one or
more of these conditions is frequently ignored. A large class of
inventors do not realise that a knowledge of scientific prin-
ciples would be an assistance in their efforts ; or if they study
science at all, they think they can acquire the necessary
knowledge by a short study, and without much trouble.

A NOTE concerning the synthesis of the chlorides of carbon
CjCI, and C^Cl,;, during the preparation of carbon tetrachloride
by the chlorination of carbon disulphide at low temperatures,
is communicated to the Berichte by Prof. Victor Meyer. It is
a well-known fact that at a red heat the vapour of carbon tetra-
chloride is dissociated, a portion of the chlorine being liberated
and the two chlorides above mentioned being produced. It now
appears that this change occurs to some extent at temperatures
but slightly elevated above the ordinary. At the chemical
works of Messrs. Miiller and Dubois, near Mannheim, carbon
tetrachloride is manufactured in large quantities by the
chlorination of carbon disulphide at temperatures between 20°
and 40°. Each operation is allowed to proceed for several
days, and the completion is indicated when the liquid has be-
come deeply coloured owing to the formation of sulphur
dichloride, SXl.j. The carbon tetrachloride is then distilled
ofi, leaving the chloride of sulphur behind. Upon rectification
of the carbon tetrachloride a quantity of a higher boiling oil is
obtained, the nature of which Prof. Meyer has investigated.
Upon fractionation it separates into three constituents,
carbon tetrachloride CCIj, the liquid chloride analogous to
ethylene CjClj, and the solid chloride CoClj, the so-called per-
chlorethane. Excellent crystals of the latter compound are at
once obtained practically pure. That a real synthesis of these
two latter compounds occurs during the manufacture of carbon
tetrachloride at so low a temperature as 20°-40°, is proved by
the fact that the carbon disulphide employed is found to be quite
pure, except for a mere trace of dissolved free sulphur. Prof.
Meyer considers that the two chlorides are produced in
accordance with the equations :

2CS., -I- loCl = CjClj -f 2S.,C1.„
2CS; -H SCI = C2CI4 + 2SXI,.

The atomic weight of bismuth has been re-determined by Frot
Schneider, of Berlin, and the result is remarkable as once more
affording exactly a whole number, 20S, as the relative weight of

i;;2

A'A TURE

[December 6, 1894

«n elementar)- atom compared with the atom of hydrogen. The
relative weight of this particularly heavy atom was determined
so long as forty-three years ago by Prof. Schneider, and the
value obtained was identical with that which is now afTorded.
Eight years after Prof. Schneider's first determination, Dumas
published the results of a number of atomic weight de-
terminations, among them being that of bismuth, to which he
assigned the value 210. From that time, 1859, until 1SS3,
Dumas' value came to be generally accepted, although no
doubt his method was by no means so little open to objection
as that employed by Prof. Schneider. However, in 1SS3
Marignac took up the subject, and as the result of determinations
carried out with the thoroughness for which he was remarkable,
the number 2o8'i6 was obtained, thus substantiating the work
of Prof. Schneider. More recently Classen has obtained a
higher result, 2oS'9, by an electrolytic method, and Prof.
Schneider has undertaken a further series of determinations with
the view of testing certain suggestions of Prof. Classen regard-
ing possibility of error in his former estimations. The method
is based upon a comparison of the equivalent relation of metallic
bismuih to bismuth trioxide. The final result obtained, if
O = 16, is 208 05, and the greatest divergence from this number
among the whole of the individual values is only o"2l. Prof.
Schneider's original work, and likewise that of Marignac, is thus
confirmed, and bismuth must now be added to the rapidly
growing list of elements whose atomic weights are represented
by whole numbers.

The aiditions to the Zoological Society's Gardens during the
past week include a Sykes's Monkey (,Cercof>itheciis alhi-
gularis, i ) from West Africa, presented by Mr. J. II. Prestwich;
a Mozambique Monkey (Cercopithecus fygfryt/iriis, i) from
East .Africa, presented by Mr. C. O. Gridley ; a Leopard
(Felis pardus) from Southern India, presented by Mr. John
Christie ; two Spotted Eagle Owls (Bubo maculosa) from
South Africa, presented by Mr. R. A. Langford ; an Antipodes
Island Parrakeet (Cyanorhamphiis uiiicolor) from Antipodes
Island, seven South Island Thrushes ( Tiirnagra crassirostris)
from South Island, New Zealand, presented by Sir Walter L.

Buller ; two Canary Finches {S,ri>iiis canariiis), (onr Frogs

{Rana, sp. inc.) from Madeira, four Dwarf Chameleons,
(Chantuleon pnmilui) from South Africa, presented by Mr. H.
Bendelack ; a Rhomb-marked Snake (^Psammophylax rhom-
htalut) from South Africa, presented by Mr. J. E. Matcham ;
an .\rctic Fox (Canis lagopiis) from the Aictic Regions,
deposited ; four Nutcrackers {Ntici/raga earyocacles), European,
purchased ; sixteen Deadly Snakes ( Tiigonocephalm alro.x), born
in the Gardens.

OUR ASTRONOMICAL COLUMN.

The New Cumf.t. — The comet of which the discovery was
announced in the last number of Nature is likely to prove
a very interesting object. A communication from Prof.
Krueger informs us that Dr. Berberich, who is probably in pos-
session of ephemcrides of the lost comets depending on various
daleo of perihelion passage, has noticed the coincidence in the
positi'jn of this comet at the first observation with that which
De Vico's comet of 1844 can assume. It will be remembered
that it was thi< same aitrunomer who conjectured from some-
what similar grounds the identity of Holmes' comet with that
of Biela. But the conjecture in this case seems to be belter
founded, for elements computed by Dr. Leuschner show a
decided similarity with those of De Vico, as computed by the
late Dr. Ilrunnow from the 1844 observations. Seeing that the
comet has undergone some fifty years' perturbations since that
time, and that the present elements arc founded on the observa-
tions of but three consecutive days, and can only be considered
as roughly approximnte, we must be prepared for some con-
tiderable deviation.

Leiischner's

elements

of Swift's

comet.

Brunnow*s

elements

of De Vico's

comet.

Long, of perihelion ... 291 48 ... 342 30
,, nodes ... 43 4 ... dl 49

Inclination 3 16 ... 2 55

Minimum distance ... I '4703 ■■• l'lS64

De Vico's comet has not been seen since 1844, though, with
a period of approximately five and a half years, nine returns
have occurred, and when the perihelia fall in the autumn, the
comet is fairly favourable for observation. There is extant, it
is true, an observation of a nebula by Goldschmidt in May
185s, which he thought might have reference to the comet, but
Brunnow could not reconcile it with the computed path, and it
is usually believed that the comet disappeared after observation
in 1844. But Le Verrier and Brunnow both thought that the
comet of 167S was identical with that of 1S44, and if this be the
case it would seem that the comet might be subject to fluctua-
tions of brilliancy, which would explain the fact of its passage
through perihelion without notice.

Further, a similarity between the elements of Finlay (1886
VII.) and De Vico has been noticed, and the agreement be-
tween those of the present comet and FinKiy's is probably more
marked than with De Vico. Tisserand's well-known criterion
of identity does not favour the supposition that De Vico and
Finlay are one and the same comet, since a very considerable
perturbative effect would have to be attributed to the action of
Mars. It would seem, therefore, more probable that several
comets are moving in approximately the same orbits than that
we have to do with the actual return of a comet lost for so
long a period as De Vico's. But under any circumstances, seeing
that the comet is diminishing in brilliancy, it is of the utmost
importance to secure observations as early and as long as
possible, since upon the accurate determination of the orbit
several important questions may finally rest. The following
positions are given in the ephemeris received from Kiel : —

R.A. Decl.

lSc4. 1). m. S.1 ,

Dec. 6 23 2 52 ... -7 so'9
„ 7 23 s 40 ... -7 311

The Si'ECTRU.M or Mars. — Prof. W. W. Campbell has
lately brought together all the observations of the spectrum of
Mars, and discussed them in connection with the telluric
spectrum and with his own observations made during the past
summer. {Ptil'Ikaliotis of iht Aflronomical Soticly oj tin Pcuific,
vol. vi. No. 37.) He concludes as follows : —

(1) The spectra of Mars and the Moon, observed under
favourable and identical circumstances, seem to be identical in
every respect. The atmospheric and aqueous vapour bands
which were observed in both spectra appear to be produced
wholly by the elements of the Earth's atmosphere. The observa-
tions, therefore, furnish no evidence whatever of a Martian
atmosphere containing aqueous vapour.

(2) The observations do not prove that Mars has no atmo-
sphere similar to our own ; but they set a superior limit to the
extent of such an atmosphere. Sunlight coming to the Earth
via Mars p.-isses twice either partially or completely through
his atmosphere. If an increase of 25 to 50 per cent, in the
thickness of our own atmosphere produces an appreciable effect,
a possible Martian atmosphere one fourth as extensive as our
own ought to be cielected by the method employed.

(3) If Mars has an atmosphere of appreciable extent, its
absorptive effect should be noticeable especially at the limb of
the jilanet. Prof. Campbell's observations do not show an
increased absorption at the limb. This portion of the investiga-
tion greatly strengthens the view that Mars has not an extensive
atmosphere.

VO. 13 10, VOL. 51]

THE ANNIVERSARY MEETING OF THE
ROYAL SOCIETY.

'T'lIE anniversary meeting of the Royal Society was held in
■*• the aparlmcnts of the Society at Hurlinglon House on St.
Andrew's Day, November 30. The auditors of the Treasurer's
accounts having presented their report, the Secretary read the
lisls of Fellows elected and deceased since the last annivers.ary
meeting. The qualificaticn of the new Fellows on the home list
were given in Nati-RE of May l7(vol. I. p. 55). The new Fellows

December 6, 1894J

NA TURE

on the foreign list are Henri Ernest Baillon, Henri Poincate,
and Eduard Suess. During the year,;the Society lost eighteen
F'ellows and three Foreign Members.

H.R.H. Louis Phillippe d'Orleans, Count of Paris, Septem-
ber 8, 1S94, aged 56.

John Tyndall, December 4, 1S93, aged 73.

The Earl of Lovelace, December 29, 1893, aged 89.

Sir Samuel White Baker, December 30, 1S93, aged 72.

Arthur Milnes Marshall, December 31, 1893, aged 41.

Pierre J. Van Beneden, January 8, 1S94, aged 93.

William Pengelly, March 16, 1S94, aged 82.

Lord Hannen, March 29, 1894, aged 73.

Dr. Charles Edouard Brown-Sequard. April I, 1894, aged 77.

Lord Bowen, April 10, 1S94, aged 58.

Biian Houghton Hodgson, May 23, 1894, aged 94.

George John Romanes, May 23, 1S94, aged 46.

Lord Coleridge, June 5, 1S94, aged 74.

Charles R. Alder Wright, July 25, 1894, aged 50.

Rev. William Bentinck Latham Hawkins, August 31, 1894,
aged 83.

Admiral Sir Edward Augustus Inglefield, September 5, 1894,
aged 74.

Hermann Ludwig Ferdinand von Helmholtz, September 8,
1894, aged 73.

Jean Charles Galissard de Marignac, September 15, 1S94,
aged 77.

William Topley, October 2, 1894, aged 53.

Lord Basing, October 22, 1894, aged 68.

Colonel R. Y. Armstrong, November I, 1S94, aged 55.

Lord Kelvin, the President, then delivered the Anniversary
Address as follows : —

Science has lost severely during the past year. In the list of
Fellows deceased, which I have read to you, you have heard the
names of Tyndall, Milnes Marshall, \'an Beneden, Pengelly,
Brown-Sequard, Romanes, Alder Wright, Helmholtz, Marignac,
Topley, all well known to you as having been in their lives
zealous and successful scientific investigators, who have largely
contributed to the object for which the Royal Society works,
"The Increase of Natural Knowledge." Tyndall, full of fire
and enthusiasm in solid experimental work advancing the
boundaries of science, contributed largely, by his brilliant
lectures and books, to make science popular, as it now is in
England and America. By the sad death of Milnes Marshall
on .Scawfell, in Cumberland, on the last day of 1S93, we lost a
young, able, and enthusiastic worker in zoology. A few
months later, we lost the veteran Pengelly, who did so much
for geological science, and gave such delightful and valuable
lessons to the larger world of not scientific geologists, in what
he did in his exploration of Kent's Cavern, Torquay.
Romanes, full of zeal, fighting to the end with the most
difficult problems that have ever occupied the mind of man, and
devoting his health and his wealth to promote not merely
philosophical speculation but also the experimental research by
which alone philosophy can have a foundation, left us at the
early age of forty-six.

A year ago, in my anniversary address, I called your attention
to Hertz's experimental demonstration of electric waves, which
he found in workmg out an expeiimental problem originally pro-
posed by Helmholtz to him when he was engaged in experimental
researches in the Physical Institute of Berlin in 1879. An
English translation by Jones, of Hertz's book describing his
work on electric waves, dedicated "with gratitude" to
Helmholtz, was published in England and America in
December 1893. On the first day of the new year the disciple
died, and within the year the master fallowed him. Of the
whole of Helmholtz's great and splendid work in physiology,
physics, and mathematics, I doubt whether any one man may be
qualified to speak with the power which knowledge and
understanding can give : but we can all appreciate, to some
degree, the vast services which he has rendered to biology by
the application of his mathematical genius and highly trained
capacity for expeiimental research to physiological investigation.

In his interesting autobiographical sketch he tells us that his
early natural inclination was for physics, which he found more
attractive than purely geometrical and algebraic studies ; but his
father could only give him the opportunity of studying physics
by his learning medicine to earn a livelihood, and he himself was
by no means averse to thus entering on the study of living matter
instead of confining himself to the physics of dead matter. 1

NO. 1 3 10, VOL. 51]

think we may now feel that the world has gained largely by this
early necessity for a young man of great genius and power to
I choose a practical profession.

j One early result was his careful examination, while still a
I student, of the theory of animal heat, and a little later (1847)
' his great essay, " Ueber die Erhaltung der Kraft," Conserva-
Mion of Energy as we now call it, communicated to the
Society of Berlin on July, 3 1847, of which he said in 1891,
" My aim was merely to give a critical investigation and
arrangement of the facts for the benefit of physiologists." As
a student he had found that Stahi's theory, ascribing to every
living body the possession of the property of "The Perpetual
Motion " as an essence of its "vital force," was still held by
most physiologi>tf." His essay on the "Conservation of
Energy," giving strong reasons for rejecting that theory, though
looked upon, at first, by many of the physical and philosophical
authorities of the time as a fantastic speculation, was enthusi-
astically welcomed by younger student philosophers, and must
soon have convinced the elder men that, whatever may be the
real efficiency of vitality, vast and wonderful as it is, it does not
include the performance of work without drawing upon a source
of energy. This conclusion had been virtually foreseen before
the end of last century by Rumford and Davy, and had been
clearly stated and powerfully supported by Joule and Mayer a
few years before Helmholtz found it for himself and successfully
persuaded others of its truth.

It is interesting for us now to know that, while thus con-
tributing so effectively to the abandonment of the old doctrine
that vital "force" can work without drawing on an external
source of energy, Helmholtz was even more effectively con-
cerned in the establishment of a new doctrine which has given
a vast extension to the province of life previously perhaps
undreamt of, but now universally recognised as thoroughly
well established, and supremely important in modern physiology
and medicine. On recovering from a typhus fever in the
autumn of 1841, at the age of twenty, the last year of his under-
graduate course in the Army Medical School of the Friederich
Wilhelm's Institute, he spent the accumulations of his income,
which free treatment at the hospital during his illness had left
him, in the purchase of a microscope, an instrument then but
little used in medical education. He began immediately to
use it, and made some important observations on the ganglion
cells of invertebrates, which, at the suggestion of his
master, Johannes Miiller, he took as the subject of his
inaugural thesis for the doctor's degree, in November 1842, and
which was his first published work.' With the same micro-
scope, he observed vibrios in putrefying liquids, which he
described in his second published paper (1S43), "On the
Nature of Putrefaction and Fermentation. " His distinguished
comrade, Schwann, in the laboratory of Johannes .Muller, had
already shown that vegetable cells are present in fermenting
solutions of sugar, and that air, which had been highly heated,
was incapable of exciting the fermentation which the access of
ordinary atmospheric air was known to produce. Helmholtz
found that oxygen, yielded by the decomposition of water in
flasks containing small pieces of boiled meat, did not produce
putrefaction. 'Thus the doctrine, held perhaps by all before
them, and certainly supported by the great Liebig, that putre-
faction and fermentation are purely chemical processes of erema-
causis (or slow combustion), produced by oxygen, was thoroughly
disproved by the two young investigators. But Helmholtz went
farther, and showed almost certainly that the actual presence of
a living creature, vibrio, as he called it, bacterium, as we more
commonly call it now, is necessary for either fermentation or
putrefaction. He proved by experiment that a partition of
moist bladder, between the yeast and the fermentable liquid, pre-
j vented the entrance of the vibrios which he had observed, una
pievcitlcd I'm fermentaticiti. It had been reasonably suggested
that fermentation or putrefaction might be a purely chemical
process produced by a quasi-chemical agent or poison secreted
I by a living organism ; but Helmholtz's observation disproved
I this supposition almost certainly, because any .^uch chemical
substance in solution would pass by diffusion through the
bladder, and produce its effect without any direct action of the
living creatures. Although Helmholtz himself was character-
istically philosophical and conscientious in not claiming, as
absolutely proved, what he had only rendered probable, it is
certain that this early work of his on putrefaction and fermenta-
tion constituted a very long step towards the great generalisa-
' Helmholtz's " Wissenschaftliche .A^handlungen," vol.-il. p. 663

^34

NATURE

[December 6, 1894

lion of Pasteur, adverse to spontaneous generation, and deci-
sive in attributing to living creatures, born fiotn previous living
creatures, not only fermentatioa and putrefaction, but a vast
array of the virulent diseases and blights, which had been most
destructive to men, and the lower animals and crops and fruits.
It is well that Helmholtz himself lived to see the great benefits
conferred on mankind by Pasteur's work ; and by the annul-
ment of the deadliness of compound fractures and the abolition
of hospital gangrene in virtue of Lister's aniisep'ic treatment ;
and by the sanitary defences against fevers and blights, realised
by many other distinguished men as practical applications of
the science which his own typhus fever of 1841 helped so much
to create.

Close after his work on this subject and on animal heat, fol-
lowed investigations on the velocity of transmission along the
sensory nerves ol the disturbance to which sensation is due, the
time which the person perceiving the sensation takes to decide
what to do in consequence, and the velocity of transmission of
his orders along the motor nerv-es to the muscles which are to
carry out his will. Results of the highest scientific interest and
of large practical importance were given in two great papers
published in 1850.' This was followed a few years later by his
" Tonempfindungen," a great work not merely confined to the
perception of sound, but including mathematical and experi-
mental investigations on the inanimate external influences con-
cerned in sound, investigation of the anatomical structure of the
ear in virtue of which it perceives sound, and applications to
the philosophical foundation of the musical art ; which holds a
unique position in the literature of philosophy, and is certainly
a splendid monument to the genius and indomitable working
power of its author. Another great work of Helmholtz is his
" Physiologische Optik " ; who shall say which of the two
books is the more important, the more interesting, or the more
valuable ? Each of them has all these qualities to a wonder-
fully high degree. Perhaps the most interesting of his experi-
mental investigations in physiological optics was the measure-
ments, by his ophthalmometer, of the curvatures of the several
refracting surfaces constituting the lens-system of the eye, from
which he ascertained that it is almost altogether by changing
the curvature of the front surface of the crystalline lens that the
eye is accommodated by its possessor to vision at different
distances. His ophthalmoscope, by which for the first time he
himself saw and showed to others the retina of the living eye,
was a splendid and precious contribution to medicine. By
allowing that outlying portion of the brain to be distinctly seen
and examined, it has shown the cause of many illnesses which
had been regarded as hopelessly obscure ; and for diagnosis and
guidance of medical treatment, it is now continually used not
only by oculists, but by general practitioners.

Constrained as I feel not to overtax your patience, I find it
impossible, on the present occasion, to enter upon Helmhollz's
researches in mathematics and mathematical physics farther than
just to mention his small but excjiiisite paper on anomalous
dispersion, and the grand contribution to hydrodynamics which
we have in his " Integrals of the Hydrodynamical Equations
which express Vottex Molion."-

Sinceour last anniversary, important questions regarding the
coodoct of the ordinary meetings and the publication of papers,
both in the Tr,i>i!<uliotis and Proiecdinp of the Royal Society,
have l.een engaging the attention of the Council, with the
assistance of a committee appointed on July 5, 1893. The
final report of this committee was submitted to the Council on
July 5, 1894, when resolutions were adopted accepting some of
it« recommendations and deferring the consideration of others
until alter the recess.

.\t the request of the Royal Geographical Society, a com-
mittee was appointed by the Council of the Royal Society to
consider the advisability of asking the Government to under-
take an .Xntarctic expedition. A very important and valuable
report ou the advantages which such an expedition would bring,
both to science and to practical navigation, was presented by
th-s committee to the Council on May 24. The Council, afier
much careful consideration, resolved to ask ih; Lords of the
Ailmiralty to grant an interview on the subject with repre-
senla'ives of the Royal Society. This request w.as assented to :
and an interview waj accordingly held between Ih; First Lord

61.
■ ton by Talt of
■•'//in 1853, and
' vVt>Mi.^UMftiit.he Alifiaodlungen, vol i.

> H-
3 /

the or..

which hai Lcc;i fcj/uUtJied li>

pp. Joi 134.

NO. 1310, VOL. 51]

of the Admiralty and representatives of the Royal Society ;
but the proposal of an Antarctic expedition was not favourably
received.

The Joule Fund Committee submitted its report on December
7, 1S93, and the Council, on its recommendation, adopted the
following resolutions : —

L That the regulations for administering the Joule-Memorial
Fund be as follows : —
11) That the proceeds be applied in the form of a studentship
or grant, to be awarded every year, to assist research,
especially among younger men, in those branches of
phy>ical science more immediately connected with Joule's
work.
(2) That this grant be international in its character, and
awarded alternately in Great Britain and abroad, or in
such order as the President and Council shall fiom time
to time decide.
(31 That it be awarded in Great Britain by the President and
Council of the Royal Society ; and, for award in France,
offered to the Academic des Sciences, P.iris ; and in
Germany to the K. Akademie der Wis-enschaften,
Berlin ; or, in any other country, to the leading scientific
institution, for award in that country.
(4; That the award in Great Britain be made on the recom-
mendation of a committee, from time to time appointed
by the President and Council of the Royal Society, but
not of necessity confined to Fellows of the Society.
n. That a sum of ;^loo, which is now, or shortly will be,
available, for the first studentship or grant be awarded in
accordance with Regulation 4.

The first appointment was accordingly madeon June 21, 1894,
when it was resolved : —
(i) " That a Joule Scholarship of the Royal Society Memorial
Fund be awarded to Mr J. D. Chorlton, of Owens
College, Manchester, for the purpose of enabling him to
carry on certain researches on lines laid down by Dr.
Joule, mor<: especially with the view of determining the
constants of some of the instruments employed by Dr.
Joule, which can be placed at his disposal by his
representatives."
(2) "That the value of the Scholarship be jfioo, payable
quarterly, on the certificate from the authorities of
Owens College that the researches are being conducted
in a satisfactory manner."
On the occasion ol Sir George Buchanan's retirement from
the post of Chief Medical Officer to the Local Government
Board, it w,as decided by some of his friends that a testimonial
should be presented to him, and a sum, amounting to about
;^340, has been subscribed by medical officers of health,
sanitary engineers, and others interested in sanitary science.
It was resolved, on the suggestion of .Sir George Buchanan him-
self, that this testimonial should take the form of a medal, to
be awarded periodically for work done in connection with
sanitary science, and that the Royal Society should be asked
to administer the testimonial fund under the following con-
ditions : —

(i) The money collected, after p.iying expenses incurred, to
be devoted —

(a) To the foundation of a Gold Medal of the value as nearly

as may be of twenty guineas, with a portrait of Sir George
Buchanan on the one side and an appropriate design on
the other, to be awarded every three or five years in
respect of distinguished services to Hygienic Science or
Practice, in the direction either of original research or of
professional, administrative, or constructive work.

(b) To the bestowal on the recipient of the Medal of the

amount (remaining after p.iying for the Medal and dis-
charging the incidental expenses) which has accumulated
since the last award.

(2) The Medal to be awarded without limit of nationality or
sex.

The Council of the Royal Society has accepted the trust
under these conditions ; and it was agreed that the first medal
should be given to Lady Buchanan by the tcstimonialists them-
selves.

The Catalogue Department has been specially active in the
past session. Mr. I.udwig Mond's generous gift of £2000,
which I announced to the .Society in my anniversary address
last year, has given a new impulse lo our operations in that
department, and enabled us lo increase the staff of assistants.
Under the able superintendence of Miss Chambers, volume 10

DLCiiMuiiu 6, 1S94J

NA TURE

^o:^

of the Catalogue under authors' names has been completed,
and was issued in June of the present year. The Society is
indebted to several members of the Catalogue Committee who
have lent their scientitic knowledge to aid in the revision of the
proofs, and especially to the Treasurer, under whose experienced
eye every sheet in the catalogue has passed. The preparation
of copy for a supplementary volume, which will include papers
from a large number of periodicals not included in the existing
volumes, is now nearing completion.

The Catalogue Committee hive held several meetings and
discussed some important questions. The proposed subject-
index to the existing catalogue has been the chief matter under
consideration, and the burning question of the respective merits
of an alphabetical and a classified index has been so far settled
as to make it possible to commence the work of transcription
and translation, nearly 40,000 slips being already finished, so
that when the details of the plan agreed upon have been finally
settled, as there is good hope they will be in the near future,
the preparation of the copy for the printer can be speedily pro-
ceeded with. Before, however, any final steps can be taken,
it will be necessary that the supplement volume of the catalogue
should have issued from the press. The preparations for this
volume are in active progress.

A kindred subject, but one of still wider scope, has been
discussed by a special committee appointed by the Council at
their first meeting in the present session. The question,
namely, of a scientific subject-catalogue, which it is proposed
to carry out by means of international cooperation. This com-
mittee, with the sanction of the Council, have addressed a
circular letter to scientific societies and institutions in this
country and abroad, offering by way of preliminary sugges-
tions, first, that the catalogue should commence with the next
century ; secondly, that a central office or bureau should be
maintained by international contributions ; and third, that this
office should be supplied with all the information necessary for
the construction of the catalogue. The circular invites the
views on this subject of scientific bodies and scientific men,
without in any way committing the Society to farther action.
A large number of replies to this circular have been received,
many of them carefully prepared and able documents. They
will be submitted to the new Council of the Royal Society, and
will, I am sure, be most valuable in assisting it to judge as to
future proceedings.

The principal question which the Library Committee have
had before them during the past session is the accumulation of
the stock of J'hilosofhual Transactions from the beginning of the
century to the present time. New racks have been erected in
the basement, which have partly relieved the pressure on our
space, but the Committee recognise the necessity of some
active measures being taken to increase the sale of this
accumulated stock. They are of opinion that the sale might
be much facilitated if the memoirs composing the volumes
published in the past were made separately available to the
public, as is done with those that are published at the present
time. On the advice of the committee, the Council have
empowered the Treasurer to treat with one of the leading
booksellers with the view of bringing some such arrangement
into effect.

The collection of marble busts belonging to the Society,
which is of such personal and historical interest to all our
Fellows, has received a most important and valuable accession.
The sons of our former President, Mr. William Spottiswoode —
Messrs. Hugh and Cyril Spottiswoode — have presented to the
Society a marble bust of their father, by Woolner, which will
find in our apartments a fitting home among the busts of many
of our former Presidents and distinguished Fellows, and will
hand down to posterity a striking likeness of one who deserved
so well of the Society and whose premature decease we all still
deplore.

The Mouse and Soiree Committee have discussed the
advisability of increasing the accommodation in the tea room,
.ind have presenied a report to the Council upon the subject.
The Council, while not disagreeing with this report, considered
it wiser, in the present state of finances, to defer the matter for
a time.

A third report of the Water Research Committee has been
issued during the present year. It gives the results of further
experiments by Prof. Marshall Ward on the " Action of Light
on Bacillus .\nthracis," and on the " Bacteria of the Thames,"
and the experiments of Prof. Percy Frankland on the

NO. 1310, vor . 5 l]

" Behaviour of the Typhoid Bacillus and of the Bacillus Coli
Communis in Potable Water," the whole filling 242 octavo
pages.

Unusually large as was the amount of matter published last
year, this year the amount is even larger. In the mathematical
and physical section of the Philosophical Transactiotis, seven-
teen papers have been published, eighteen in the biological
section. The two sections together contain, in all, 1992 pages
of letterpress, and 112 plates ; to which must be added eight or
ten papers now passing through the press, and probably to be
issued before the close of the year. Of the Proceedings, ten
numbers have been issued, containing 1026 pages. As a result,
the finances of the Society are, I regret to say, in not such a
satisfactory condition as could be desired. The cost o'
the publications, which, last year, was far in excess of
what it was in previous years, and of what the Society
could really afford, has, in the year 1S94, amounted to nearly
;£'326o, or about £<)qs more than it was in 1893. For litho-
graphy and engraving alone ;i^i5i6 have been paid, as againsr
£S11 last year. There is, moreover, an accumulation of
printed matter now almost in readiness to be issued, the cost of
which has still to be defrayed. To meet this extraordinary
expenditure it has been necessary to sell out enough of the
Society's funded capital to produce ^1000, and rigorous re-
trenchment will be necessary in order to avoid further loss ol
provision for continued work in future. While the Council
feels the importance of all the publications of the Society being
as completely illustrated and as fully detailed as the subjects
discussed may require, it is evident that some check must be
placed on the extent of the publications, and the best manner
of effecting this end is occupying the careful attention of the
Council.

The establishment of the Faraday-Davy Research Labora-
tory, in connection with the Royal Institution, is a splendid
benefaction which science has gained during the past year,
through the untiring and grand generosity of Mr. Ludwig \Iond.
The Royal Society interests itself in all work contributing
towards the object for which it was founded — the increase ol
natural knowledge ; and while gratefully remembering the
assistance so generously given to it in the humble but highly
valuable work of cataloguing papers which describe the results
of scientific investigations already made, it hails with delight
this grand foundation of a practical laborator)', of which the
purpose is not the teaching of scientific truths already discovered,
but the conquering of fresh provinces from the great region of
the unknown in nature.

The greatest scientific event of the past year is, to my mind,
undoubtedly the discovery of a new constituent of our atmo-
sphere. If anything could add to the interest which we must all
feel in this startling discovery, it is the consideration of the way
by which it was found. In his presidential address to Section
A of the meeting of the British Association at Southampton in
18S2, Lord Raylergh, after calling attention to Prout's law,
according to which the atomic weights of the chemical elements
stand in simple relationship to that of hydrogen, said : — -"Some
chemists have reprobated strongly the importation of A priori
views into the consideration of the question, and maintain that
the only numbers worthy of recognition are the immediate results
of experiment. Oihers, more impressed by the argument
that the close approximations to simple numbers cannot
be merely fortuitous, and more alive to the inevitable;
imperfections of our measurements, consider that th<-
experimental evidence against the simple numbers is of a
very slender character, balanced, if not outweighed, by th--
1) priori argument in favour of simplicity. The subject i<
eminently one for further experiment ; and as it is now-
engaging the attention of chemists, we may look forward to the
settlement of the question by the present generation. The
time has, perhaps, come when a redetermination of the densities
of the principal gases may be desirable — an undertaking for
which I have made made some preparations." The arduous
work thus commenced in 1882, has been continued for twelve
years,' by Rayleigh, with unremitting perseverance. After

t "On the rcl-itive Densities of Hydrogen .ind Oxygen. Preliininary
Notice," by Lord R.-iyleigti, February a, i3S3. '* On the Compcsition ■ f
Water." by Lord R.-iylcith, P'ebruary 26, 1889. "On the relative Densities
of Hydrogen and Oxygen. IL" By Lord Rayleigh, Februarj- 5. xSg:.
" On the Densities of the principal Gases," bylAjrd Rayleigh, March 23.1893.
"On an .-Vnomaly encountered in Determinations of the Density of Nitrogen
G.as." by Lord Rayleigh, April 19, 1894. All published in the PivceeHings
of the Royal Society.

136

NA TURE

[December 6, 1894

twelve years of it, a first importaot part of the object, the
determinalion of the atomic weight of oxygen with ail possible
accuracy was attained by the comparison,' of Scott's determina-
tion of the ratio of the volumes of hydrogen and oxygen in the
constitution of water, with Rayleigh's determination of the
ratio of the densities. The result wa> 15S2, which is almost
I per cent. (0S7 per cent.) less than the 16, which it
would be according to Prout's law. It is very slightly less
(I per cent.) than Dittmar and Henderson's value obtained by
an investigation- for which the Graham medal of the Glasgow
Philosophical Society was awarded in 1S90. Valu:s, not quite
so small as tlie-e for the atomic weight of oxygen, had been
previously found by Cooke and Richards (15869) and by Leduc
(15 876). There can be no doubt whatever now that the true
value is more than \ per cent, smaller than according to Trout's
law, and that in all probability it agrees exceedingly closely
with the results o!)tained by Rayleigh and Scott, and liy Dittmar
and Henderson. The question of Pioul's law being thus so far
set at rest, Rayleigh, persevering in the main object which he
had promised in 1SS2, "a redetermination of the densities of
the principal gases," attacked nitrogen resolutely and, stimulated
by most disturbing and unexpected difficulties in the way of
obtaining concordant results for the density of this gas as
obtained from diSferent sources, discovered that the gas obtained
by taking vapour of water, carbonic acid, and oxygen from
common air was denser-' by i 230 than nitrogen obtained
by chemical processes from nitric oxide or from nitrous
oxide, or from ammonium nitrite, thereby rendering it
probable that atmospheric air is a mixture of nitrogen, and a
small proportion of some unknown and heavier gas. Rayleigh
and Ramsay, who happily joined in the work at this stage, have
since succeeded in isolating the new gas, both by removing
nitrogen from common air by Cavendish's old process of passing
electric sparks though it, and taking away the nitrous com-
pounds thus produced by alkaline liquor; and by absorption
by metallic magnesium. Thus we have a fresh and most in-
teresting verification of a statement which I took occasion to
make in my presidential address to the British Association in
1871,'' " Accurate and minute measurement seems to the non-
scientific imagina'ion a less lofty and dignified work than look-
ing for something new. But nearly all the grandest discoveries
of science have been but the rewards of accurate measurement
and patient long-continued labour in the minute sifting of
numerical results." The investigation of the new gas is now
being carried on vigorously, and has already led to the wonder-
ful conclusion that the new gas does not combine with any
other chemical substance which has hitherto been presented to
it. We all wait wiih impatience for further results of their
work ; we wish success to it, and we hope that it will give us,
before the next anniversary meeting of the Royal Society,
much knowledge of the properties, both physical and chemical,
of the hitherto unknown and still anonymous fifth constituent of
our atmosphere.

Copley Medal.

Dr. Edward Frankland, !■'. K. S.

The Copley Medal is awarded to Dr. E. Frankland for his
eminent services to theoretical and applied chemistry.

At a time when the classification of organic compounds in
homologous series was a comparative novelty, when isomerism
was still a profound mystery, and the theory of compound
radicles introduced by Liebig was still on its trial, Dr. Frankland
made his first attempt 'in 1S48) to isolate the radicle of common
alcohol. Though the attempt was in one sense unsuccessful,
ina.<much as the free radicle was never obtained, for reasons
which we now more fully understand, the research led to
important consequences. The discovery of the organo-melallic
compriunds, and the study of their composition and properties,
wax followed by a recognition of the fact, first that the capacity
for combination possessed by the atoms of the metals was
limited (I'hil. 7'raiii., 1852), and secondly that variation of
"atomicity," as it was then called, usually occurs by an even
number ol units (yoiini. Chcm. Soc, 1866), represented by
alomi of hydrogen, chlorine, or such compound radicles as
methyl, ethyl, and the rest. These discoveries form the basis

* Scoll, '■ On the Composition of Water by Volume." communicated by
Lord kayl^ie**. f^fy ^01- i'rac, March 2\. iSoj.

2 /• ^ ' •' - '■ ' ■ -' ^ V of Glalgow, 1890-1891.

a - '-rminalion^ of the Density of

\itr

* K^l' 1^ I rir J >n ■ >i ii .i t'u'ii..i ,. ...turet ftoU Addresses."

of the modern doctrine of valency, with all the important
consequences that follow, including the idea of the orderly
linking of atoms, and hence the theories of structure or
constitution now current.

The discovery of zinc ethyl placed in the htinds of chemists
an important new instrument of research, which Dr. Frankland
was himself the first to use in his investigations concerning the
synthetical production of acids of the lactic and acrylic series.
Further important synthetical work, conducted in concert with
Mr. Duppa, led to a method of ascending the series of acids
homologous with acetic acid.

Dr. Frankland's researches in pure chemistry are almost
rivalled in interest by his discoveries in physical chemistry,
especially in relation to the influence of pressure on the rate of
combustion, on the light emitted during combustion, and on
the cause of luminosity in hydrocarbon flames.

The important work done by Dr. Frankland in the study of
water supply and sewage, and illuminating gas, has proved of
great practical value, and has rendered his name famous in
connection with the application of chemistry to technical
purposes.

RuMFORD Medal.

Professor Dr,var.
During more than twenty years past Prof. Dewar has been
engaged in researches of great difficulty, in the first instance at
very high, and latterly at very low temperatures, his inquiries
having extended over an extraordinary wide field, as will be
seen by reference to the "Royal Society Catalogue" of
scientific papers.

In conjunction with Prof. Liveing, he has communicated to
the Royal Society a large number ot papers which have added
much to our knowledge of spectroscopic phenomena.

During recent years he has made the liquefaction of gases a
subject of deepest study, and in the course ol this work has
displayed not only marvellous manipulative .skill and fertility of
resource, but also great personal courage, such researches being
attended with considerable danger. One of his chief objects
has been so to improve and develop the methods of liquefying
the more permanent gases that it shall become possible to deal
with large quantities of liquid, and to use such liquids as instru-
ments of research in extending our knowledge of the general
behaviour of substances at very low temperatures. In this he
has already been highly successful. Not only has he suc-
ceeded in preparing large quantities of liquid oxygen, but he
has been able by the device of v.acuuni-jacketed vessels to
store this liquid under atmospheric pressure during long
periods, and thus to use it as a cooling agent. Very valuable
outcome of these labours has been the series of determinations,
made by him in conjunction with Dr. Fleming, of the electrical
conductivity of metals at exceedingly low temperatures, which
have furnished results of a most unexpected character, and of
extraordinary interest and importance. Prof. Dewar's experi-
ment showing the great magnetic susceptibility of licjuid oxygen
is exceedingly important and interesting. His recent observa-
tions on phosphorescence, and on photography,' and on ozone-
at very low temperatures, have given surprising results of a
highly instructive and interesting character. It is difficult to
exaggerate the importance of extending these researches, which
certainly deserve all possible encouragement and support. The
award of the Rumford Medal to Prof. Dewar is made in
recognition of the services which he h.is rendered to science by
the work which he has already done and the provision he has
been .successful in making for future work, in the investigation
of properties of matter at lowest temperatures.

Royal Medal.
Prof. J. J. Thomson, KA'.S.

Prof. 1. J. Thomson has distinguished himself in both mathe-
matical and experimental fields of work. His first essay on
vortex rings showed power of grappling with difficult problems,
and added to our knowledge concerning the encounter of rings
which came within a moderate distance of one another so .is
to deflect each others' paths.

His theoretical work in the borderland of chemistry and
physics has been very interesting and suggestive. His cxperi-
menial work has likewise been mainly on the borders of
chemistry and physics. He has observed the large conductivity

t Chfiii. See, Prt't., June 28, 1894.

-' /'//// Ma/.:, August i&^4, pp. 3j8, ajy.

NO. 13 10. i'OL. 51]

December 6, 1894J

NA TURE

•37

of many gases and vapours, and proved the non-conducting
power of several others", founding on the conducting power of
iodine vapour important speculations as to its probable
chemical constitution.

He has also measured the specific resistance of various
electrolytes, under extremely rapid electric oscillations, by an
ingenious and valuable method, based on the partial opacity of
semi-conducting matter to electromagnetic waves. Recently
he has worked at the discharge of electricity thiough rarefied
gases, getting induced currents in closed circuits in sealed bulbs
without electiodes, and, in especial, measuring to a first ap-
proximation the absolute velocity of the positive discharge through
a long vacuum tube, proving that it was comparable with,
though decidedly less than, the velocity of light. lie also gave
an ingenious theory of the striae— a theory which he has since
endeavoured, with some success, to extend to a large number of
electrical phenomena, the whole of electric conduction and in-
duction being regarded by him from the chemical side as a
modified or incipient electrolysis, or as concerned with electro-
lytic chains of molecules or " Faraday tubes."

Some of his recent mathematical work on the theory of
electric oscillations in spheres and cylinders, and in dumb-bell
oscillators of the kind used by Hertz, with reference to not only
their oscillation-frequency but also their damping efficiency,
has been of much service to experimental workers in those
branches of physics. And, in general, the effective manner in
which he attacks any electrical problem presenting itself, as
evidenced by his book on " Recent Researches iii Electricity
and Magnetism," wherein he worthily carries on into a thiid
volume the great treatise begun by Clerk Maxwell, is evidence
of consummate ability combined with remarkable energy and
power of work.

Royal Medal.
Picf. Victor HorsUy, F.R.S.

A Royal Medal is awarded to Prof. Victor Horsley, F.R.S.,
for his laborious and fruitful researches in physiology and
pathology, and particularly for those relating to the functions of
the nervous system and of the thyroid gland. His inquiries
relating to the former subject have been pursued for more than
ten years, and have been communicated to the Royal Society in
a succession of papers, the most important of which have been
published in the Philosophical Transactions. The first of the
series of researches (/'/;;/. Trans., |8S8), which was conducted
in co-operation with Prof. Schiifer, and concerned the relation
of a part of the cerebral cortex (the limbic lobe) to sensation,
afforded a new confirmation and extension of the doctrine of
the localisation of cerebral function now generally accepted.
While this work was in progress. Prof Horsley engaged with
Dr. beevor in a long and laborious series of experiments for the
purpose of determining with the utmost attainable accuracy the
nature of the muscular responses which are evoked by stimulat-
ing the convolutions in the quadrumana. The results of these
researches were communicated in four papers, of which the first
three relate to the "cortical representations ' of the movement
of the limbs, and of those of the tongue and face (/'/;// Trans.,
1887-1890) ; the fourth on the channels (in the internal capsule)
by which the cortex exercises its influence on the rest of the
nervous system (/VhY. Trans., 1S90).

These experiments not only served to bring to light a number
of new facts, and to elucidate their physiological relations in a
very remarkable way, but had a special interest in their bearing
on the physiology and pathology of the brain in man. Their
importance in this respect is enhanced by the circumstance that
in the course of the inquiry the opportunity offered itself of
comparing the brain of the monkey with that of the orang
(Phil. Trans., 1890), a brain which so closely approaches that
of man in its structure that the knowledge acquired by these
researches may now be confidently used as a guide in the dia-
gnosis and treatment of cerebral disease. Prof. Horsley has
himself shown — and this is not the least of the merits which it
is desired to recognise in the bestowal of the Royal Medal — in
how many instances the knowledge which is acquired by patient
and skilful work in the laboratory may be made available for
the saving of life, or the alleviation of human suffering.

In connection with this leading series of researches, two
others relating to the physiology of the central nervous system
must be referred to. In one of these {Phil. Trans., 1890),
Prof. Horsley (in co-operation with Dr. Semon) established the
existence, not only of a co oniinating centre in the liulh, but of

NO. 1310, VOL 5 l]

a cortical area in physiological relation with the respiratory and
phonatory movements of the larynx ; in the other, in conjunc-
tion with Prof. Golch, he investigated the electrical changes in
the spinal cord which are associated with excitation of the
cortex and internal capsule, and showed how the observation of
these facts can be made available for tracing channels of con-
duction in the cord.

As regards the thyroid gland, Pi-of. Horsley's inquiries relat-
ing to functions of that organ were like those relating to the
nervous system, begun ten years ago, though the results were
not communicated to the Royal Society until three years later.
Their purpose was to ascertain the nature of the very marked
influence which the thyroid was known to exercise on the
nutritive functions of the organism, and to show that ihis influ-
ence is constant and definite. In this field. Prof Horsley has
not only the merit of having been one of the earliest workers,
but of having at ihis early period arrived at results which the
numerous investigations of subsequent writers have in all
essential particulars confirmed.

D.WY Medal.
Prof. Peter Theodor Clez'c.

The Davy Medal is awarded to Peter Theodor Cleve, Pro-
fessor of Chemistry in the University of Upsala, for his services
to chemical science during the last thirty year.s, and in particular
for his long-continued and valuable researches on the chemistry
of the rare earths.

This field of inquiry is pre-eminently Scandinavian. By the
manner in which he has cultivated it, Prof Cleve has shown
himself a worthy successor of such forerunners as Gadolin,
Berzelius, and Mosander, and by sound and patient investigation
he has faithfully upheld the traditions inseparably associated
with these names. All chemists are agreed that no department
of their science demands greater insight or more analytical skill
than this particular section. Many of the minerals which furnish
the starting-point for investigation are extremely rare, and the
amounts of the several earths which they contain are frequently
very small. Moreover, the substances themselves are most
difficult of isolation, and their characters are so nearly allied that
the greatest careandjudgment are requiredin order todetermine
their individuality.

A remarkable example of Prof Cleve's power in overcorning
these difficulties is seen in his masterly inquiry into the affinities
and relations of the element scandium, discovered by Nilson.
This, one of the rarest of the metals, is found only in gadolinite
to the extent of o'OOj per cent., and inytirolitanite to the extent
of about 0'005 per cent. The whole amount of the material, as
oxide, at Cleve's disposal was only about I gram, but with
ihii small quantity he determined the atomic weight of the
element, and ascertained the characters of its salts with such
precision as to leave no doubt of the identity of scandium with
the element Ekabor, the existence of which w.as predicted by
Mendeleef, in the memorable paper in which he first enunciated
the Law of Periodicity. Cleve's research, indeed, constitutes
one of the most brilliant proofs of the soundness of the great
generalisation which science owes to the Russian chemist.

A not less remarkable instance of Cleve's skill as a worker is
seen in his research on samarium and its compounds, which he
communicated as one of its Honorary Foreign Fellows to the
Chemical Society of London. The existence of samarium was
inferred independently by Delafontaine ami Lecoq de Bois-
baudran, but we owe to Cleve the first comprehensive in-
vestigation of its characters and chemical relations. From the
nature of its compounds, a large number of which were first
prepared and quantitatively analysed by Cleve, and from the
value of its atomic weight, which was first definitely established
by him, it would appear that samarium most probaoly fills a gap
in the eighth group of -Mendelcef s system.

We are further indebted to Cleve for a series of determinations
of the atomic weights of the rare substances yttrium, lanthanum,
and didymium ; these are generally accepted as among the best
authenticated values for these particular bodies.

No record of Cleve's scientific activity would be complete
without some reference to his investigations in the domain of
organic chemistry, and more particularly to his studies, extend-
ing over twenty years, of naphthalene derivatives. By these
researches, made partly independently, and partly in conjunction
with his pupils, among whom may be named .Vtterberg, Widman,
Forsiing, and Hellstr<im, Cleve has gradually brought order out
of confusion, and has supplied most valuable experimental

I3S

NATURE

[DECEArBEK 6, 1804

evidence of the constitution of naphthalene, and of the course of
substitution of naphthalene derivatives. Within recent years a
score ofworkers have occupied themselves with the same field of
research, and no greater proof of Cleve's accur.-icy and care as
an investigator could be furnished than the manner in which his
naphthalene work — confessedly one of the most intricate and
complicated sections of the chemistry of aromatic compounds —
has stood the ordeal of revision.

Darwix Medal.

Ri^hilflon. T. H. HuxUy, F.R.S.

The Darwin Medal is awarded to Thomas Henry Huxley.

Of Mr. Huxley's general labours in biological and geological
science I need say nothing here. They are known of all men,
and the Society showed its appreciation of their worth when it
awarded lo him the Copley Medal in 1SS8. The present medal
is a token of the value put by the Society on the part of his
scientific activity bearing more directly on the biological ideas
with which the name of Charles Darwin will always be
associated.

All the world now knows in part, no one perhaps will ever
know in full, how, in the working out of his great idea, Darwin
was encouraged, helped, and guided by constant communion
with three close and faithful friends, Charles Lyell, the younger
Joseph Dalton Hooker, and the still younger Thomas Henry
Huxley. Each representing more or less different branches of
science, each bringing to bear on the problems in hand more or
less different mental characters, all three bore share, and were
proud to bear share, in aiding the birth of the " Origin of
Species." Charles Lyell has long been removed from amongst
our midst. Two years ago it was my pleasing duty to ulace the
Darwin Medal in the hands of Joseph Dalton Hoo ^r; that
pleasing duly is renewed today in now giving it to the last of
the three "who kept the bridge."

To the world at large, perhaps, Mr. Huxley's share in mould-
ing the thesis of " Natural Selection" is less well known than
is his bold unwearied exposition and defence of it after it had
been made public. And, indeed, a speculative tiifler, revelling j
in problems of the "might have been," would find a congenial i
theme in the inquiry how soon what we now call " Darwinism "
would have met with the acceptance with which it has met, and 1
gained the power which it has gained, had it not been for the
brilliant advocacy with which in its early days it was expounded
to all classes of men.

That advocacy had one striking mark ; while it made or strove |
to make clear how deep the new view went down and how far
it reached, it never shrank from striving to make equally clear
the limits beyond which it could not go. In these latter days
there is fear lest the view, once new but now familiar, may,
through being stretched farther than it will bear, seem to lose
some of its real worth. We may well be glad that the advocates
of the "Origin of Species by Natural Selection," who once bore
down its foes, is still among us ready, if needs be, 10 "save it
from its friends."

The Society next proceeded to elect the officers and Council
for the ensuing year. We gave the list of those recommended
for election in our issue of November S.

In the evening the Fellows and their friends dined together
at the Whitehall Rooms of the H.'.lel .Mclropole.

After the usual toasts, the President proposed that of "The
Medallists," cou^lir.g with it the names of Prof. Cleve and
Mr. Huxley. The toast was most cordially drunk. The
Times reports the responses as follows : —

Prof. Cleve, in responding, quoted ihe noble words of Davy—
"Science, like that nature to which it is bound, is neither
limited by time nor by space ; it belongs to Ihe world, and is
of no country and of no age." In the same sense the Royal
Society continued lo award its medals to men of science, with-
out regard to their nationality. It was a g'eat and elevating
thought that there existed a spot in the world where members
of all nations met each other as friends, assisting each other in
their work for the advancement of science, aiid theicforc for ihe
good of humanity and the prosperity of mankind. It was the
first lime that the Davy medal had found its way to Sweden,
but it was not the first time that other medals of Ihe Koyal
Society had been voled to Professor.^ of the Vnivcrsity lo which
he was attached. The Kumfoid medal had been given not less
than three limes lo his colleagues, and when he offered to the

NO. t3IO, VOL 51]

Royal Society his respectful thanks he was happy to include also
those of the University of Ipsala.

Mr. Huxley said— I am extremely grateful for the respite which
has been afforded me by the distinguished f ireigner to whom
you have just been listening with so much pleasure, because I
am loaded with five distinct and separate parcels of gratitude.
That is a substance of which I believe the specific gravity has
never yet been accurately determined. I am told that in some
parts of the world, and especially in the political world, it is
lighter than hydrogen ; but in the scientific world, and when
the object of it is the approbation of a body like ihe Royal
Society, I am disposed to think that we may rank it rather with
platinum, so largely does it affect the destinies of those who are
fortunate enough to receive it. In respect of four of these
paicels I am simply a representative, and perhaps I ought to
content myself with acting purely as a representative of those
who I wish had been called upon to express their gratitude for
themselves. But pet haps I may venture to add that in some
cases I have a little personal word to say for myself, as, for
example, in that of the Copley medal, which you have adjudged
one of my oldest friends and many years a colleague, so that I
have a strong and warm interest in the fact that his great
services to the science of chemistry have been recognised. .'Vnd,
again, I think that there is another friend in whom I may
claim a personal interest— I mean my friend Prof. De war— for
the remarkable character of his discoveries allows a person who
indulges so little in flights of imagination as myself to think of the
time when, instead of the excellent liquid with which we have
been supplied here, we may have at these dinners of the Royal
Society liquid oxygen Hen Jrafpc, and then, gentlemen, with
that stimulus there is no saying to what length the eloquence
of persons who address you may go. .\nd then, again, in one
of the youngest of those whom you have honoured with your
approbation to day, and whose work lies within the province
in which I am still capable if not of knowledge at le.ist of appre-
ciation—I mean Prof. Victor Horsley— I may say that it is
pleasant to nie to see him here like a Ulysses who has escaped
from the toils of the Circes of anti vivisection. Hut the most
difficult task that remains is that which concerns myself. It is
forty-three years ago this day since the Koyal Society did me
the honour to award me a Royal medal, and thereby determined
my career. But, having long retired into the position of a
veteran, I confess I was extremely astonished — 1 honestly also
say that I was extremely pleased— to receive the announcement
that you had been good enough to award to me the Darwin
medal. But you know the Royal Society, like all things in this-
world, is subject to criticism. I confess that with the ingrained
instincts of an old official that which arose in my mind alter the
reception of the information that I had been thus disiinguished
was to start an inquiry which I suppose suggests itself to every
old official— How can my government be justified ? In reflect-
ing upon what had been my own share in what are now very
largely ancient transactions it was perfectly obvious to-
me that I had no such claims as those of Mr. Wallace.
It was also perfectly clear lo me that I had no such claims as
those of my life-long friend Sir Joseph Hooker, who for twenty-
five years placed all his great sources of knowledge, his sagacity,
his industry, at the disposition of his friend Darwin. And
really, I began to despair of what possible answer could be
given to the critics whom the Koyal Society, meeting as it does
on November 30, has lately been very apt to hear about oiv
December i. Naturally there occurred lo my mind that famous
and comfortable line, which I suppose has helped so many
people under like circumstances, " They also serve who only
stand and wail." I am bound to confess that the standing and
waiting lo which I refer, has been, so far as I am concerned, of
asome»hat peculiar character. I can only explain it, if you
will permit me lo narrate a story which came to me in my old
naulic.-il days, and which, I believe, has just as much foundation
.IS a good deal of other information which I derived at the same
period from ihe same source. There was a merchant ship itt
which a member of the Society of Friends had taken passage.
That ship was attacked by a pirate, and the captain thereupon
put into ihe hands of the member of the Society of Friends a
pike, and desired him lo lake part in the subsequent action,
to which, as you may imagine, the reply was that he would do
nothing of Ihe kind ; but he said that he had no objection lo stand
and wail at the gangway. He did stand and wait with the pike
in his hand, and when the pirates mounted and showed
ibemselvcs coming on board, he thrust his pike (with the

December 6, 1894J

NATURE

139

sharp end forward) into the persons who were mountinp,
and he said, " Friend, keep on board thine own ship." Ic is
in that sense that I venture to interpret the principle of stand-
ing and waiting to which I have referred. I was convinced as
firmly as I have ever been convinced of anything in my life
that the " Origin of Species " was a ship laden wiih a cargo of
great value, and which, if she were permitted to pursue her
■course, would reach a verit-able scientific Golconda, and I
thought it my duty, however naturally averse I might be to
■figliiing, to bid those who would disturb her beneficent opera-
tions to keep on board their own ship. If it has pleased the
Royal Society to recognise such poor services as I may have
ren'lered in that capacity I am very glad, because I am as much
convinced now as I was thirty-four years ago that the theory
propounded by Mr. Darwin, I mean that which he propiunded
— not that which has been reported to be his by too many ill-
■instiucted, both friends and foes — has never yet been shown to
te inconsistent with any positive observations, and if I may use
a phrase which I know has been objected to and which I use in
a totally different sense from that in which it was first proposed
ty its first propounder, I do believe that on all grounds of pure
science it "holds the field," as the only hypothesis at present
tefore us which has a sound scientific foundation. It is quite
possible that you will apply to me the remark that has often
teen applied to persons in such a position as mine, that we are
apt to exaggerate the importance of that to which our lives
have been more or less devoted. But I am sincerely of opinion
that the views which were propounded by Mr. Darwin
thirty-four years ago will be understood hereafter to maik
an epoch in the intellectual history of the human race.
They will modify the whole system of our thoughts and
opinions, and shape our most intimate convictions, I do not
know, I do not think anybody knows, whether the particular
•views which Darwin held will be fortified by the experience of
the ages which come after us. But of this thing I am perfectly
■certain, that the present state of things has resulted from the
feeling of the smaller men who have followed him that they are
incompetent to bend the bow of Ulysses, and in consequence
many of them are preferring to employ the air-gun of mere specu-
lation. Those who wish to attain to some clear and definite
solution of the problems which Mr. Darwin was the first person
to sec before us in later times, must base themselves upon the
facts which are stated in his great work, and, still more, must
pur^ue their inquiries by the methods of which he was so brilliant
an exemplar throughout the whole of his life. Vou must have
his sagacity, his untiring search after the knowledge of fact, his
readiness always to give up a preconceived opinion tothat which
was demonstrably true, before you can hope to carry his doctrines
to their ultimate issue ; and whether the particular form in which
lie has put them before us may be such as is finally destined to
survive or not is more, I venture to think, than anybody is capable
at this present moment of saying. But this one thing is perfectly
certain — that it is only by pursuing his methods, by that won-
derful single-mindedness, devotion to truth, readiness to sacrifice
■all tilings for the advance of definite knowledge, that we can hope
to come any nearer than we are at present to the truths which he
Struggled to attain.

THE BA TTLE OF THE FORESTS.^

II.

TN the sand-hills which traverse Nebraska from east to west
there are now found in eastern counties the sand-drowned
trunks of the western bull pine, and the same pine belonging to
the Pacific flora is found as.ociated with the black walnut of
the eastern region along the Xiobrara River.

We may, however, divide the North American forest, accord-
ing to its botanical features, into two great forest regions,
namely, the Atlantic, which is in the main characterised by
broad-leaved trees, and the Pacific, which is made up almost
.vholly of coniferous species.

In the Atlantic forest we can again discern several floral sub-
divisions, each of which shows special characteristics. The
souihernmosl coast and keys of Florida, although several degrees
north of the geographical limit of the tropics, present a truly

* A lecture delivered by Prof. li. E. Fernow. Chief of the Forestry
Depart tiicnt of Agriculture, U.S.A., during the Brooklyn meeting of the
American Association for the Advancement of Science. (Continued from
page 119.)

tropical forest, rich in species of the West Indian flora, which
here find* its most northern extension. There is no good reason
for calling this outpost semi-tropical, as is done on Sargent's
map, W'ith the mahogany, the mastic, the royal palm, the
mangrove, the sea grape, and some sixty more W'est Indian
specits represented, it is tropical in all but its geographic posi-
tion. That the northern flora joins the tropic forest here, and
thus brings together on this insignificant spot some hundred
species, nearly one quarter of all the species found in the Atlantic
forest, does not detract from its tropical character.

On the other hand, the forest north of this region may be
called sub-tropical, for here the live and water oak, the mag-
nolia, the bay tree and holly, and many other broad-leaved trees
are mixed with the sabal and dwarf palmatto. As they retain
their green foliage throughout the winter, this region is truly
semi-tropical in character, and under the influence of the Gulf
Stream, extends in a narrow belt some twenty or twenty-live
miles in width along the coast as far north as North Carolina.

While this ever-green, broad-leaved forest is more or less
confined to the rich hammocks and moister situations, the poor
sandy soils of this as well as of the more northern region are
occupied by pines ; and as those, especially the long leaf pine,
are celebrated all over the world, and give the great mercantile
significance to these forests, this region may well be called the
great southern pine belt. North of the evergreen subtropic
forest stretches the vast deciduous leaved forest of the Atlantic,
nowhere equalled in the temperate regions of the world in ex-
tent and perfection of form, and hardly in the number of
species. This designation applies to the entire area up to the
northern forest belt, for the region segregated on the
census map as the northern pine belt is still in the main the
dominion of the deciduous-leaved forest trees. On certain areas
pines and spruces are intermixed, and on certain soils, especially
gravelly drifts and dry sand plains, as on the pine barrens of
Northern Michigan, they congregate even to the exclusion of
other species. Instead, we can divide this deciduous-leaved
forest by a line running somewhere below the fortieth degree of
latitude, where with the northern limits of the southern mag-
nolias and other species we may locate in general the northern
limit of the southern forest flora. Northward from here, in
what may be called the " middle Atlantic forest," the deciduous
species rapidly decrease, and the coniferous growth predomi-
nates, until we arrive at the broad belt of the northern forest,
which, crossing from the .-Vtlantic to the Pacific, and composed
of only eight hardy species, takes its stand against the frigid
breath and icy hands of Boreas,

.\bounding in streams, lakes, and swampy areas, the low
divides of this region are occupied by an open stunted forest of
black and white spruce, while the bottoms are held by the
balsam fir, larch or tamarack, poplar, dwarf birch and willow.
Tne white spruce, paper or canoe birch, baUam poplar and
aspen stretch their lines from the Atlantic to the Pacific over
the whole continent.

On the Pacific side the subdivisions are rather ranked from west
to east. While the northern forest battles against the cold blasts
from icy fields, the front of the Pacific interior forest is wrestling
with the dry atmosphere of the plains and interior basin. Here,
on the driest parts, where the sage brush finds its home, the
ponderous bull pine is the foremost fighter, and where even this
hardy tree cannot succeed in the interior basin several species of
cedar hold the fort, in company with the nut pine, covering
with an open growth the mesas and lower mountain slopes.
Small and stunted, although of immense age, these valiant
outposts show the maiks of severe struggles for existence.

On the higher, and therefore moister and cooler elevations,
and in the narrow canyons, where evaporation is diminished
and the soil is fresher, the sombre Douglas, Engelmann, and
blue spiuce, and the silver-foliaged white fir, join the pines or
take their place.

With few exceptions, the same species, only of better de-
velopment, are found in the second parallel, which occupies the
western slopes of the .Siena Nevada. Additional forces here
strengthen the ranks, the great sugar pine, two noble firs, a
mighty larch, hemlocks and cedars vie with their leaders, the
big sequoias, in showing of what metal they are made. The
third parallel, occupied by the forest of the Coast Range, the
most wonderfully developed, although far from being the most
varied of this continent, is commanded by the redwood, with
the tide-land spruce, hemlock, and gigantic arborvitae -joining
the ranks.

5-1

I40

NATURE

[DECEMbEK 6, 1894

Broad-leaved trees are not absent, but so little developed in
compariion with the mighty conifers that they play no conspi-
cuous part except along the river bottoms, where the maple,
Cottonwood, ash, and alder thrive, and in the narrow interior
valleys, where an open growth of oak is found. Towards the
south and on the lower levels these broad-leaved trees again
become evergreen, as on the Atlantic side, but of different
tribes, and form a sub-tropic flora.

Along the coast we find several species of true cypress, in-
cluding the well-known, although rare, Monterey cypress, which
clings to the gigantic rocks, and braves the briny ocean winds,
and with its branches twisted landward. Finally, flanking the
battle order of the Pacific forest, we find another section of the
army, composed of the northern extension of the Mexican flora,
mingled with which are species from the Pacific forest on the
west, and from the Atlantic on the east.

The mesquile and some acacias, the tree yuccas and the
giant or tree cactus are perhaps the most characteristic and
remarkable species of the deserts of this region, while the high
mountains support dense forests of firs and pines.

So far we have considered the forest only from the geo-
graphical and botanical point of view, and have watched the
history of its struggle for existence against the elements and
against the lower vegetation and other forces of nature. \ new
chapter of its life history, which we shall have time only to
scan very briefly, began when man came upon the scene, and
the economic point of view had to be considered.

For ages man has taken sides against the forest. Not only
has he contested for the occupancy of the soil, in order to culti-
vate his crops or to make the meadow for his cattle — a most
legitimate and justifiable proceeding — and not only has he utilised
the vast stores of wood accumulated through centuries, for the
ten thousand uses to which this material can be applied, and
in the application of which he exhibits his superior intelligence,
but he has also shown a woeful lack of intelligence in the wilful
or careless destruction of the forest without justifiable cause,
and by just so much curtailing the bountiful stores provided
by nature for him and his progeny. Not only has he, like a
spendthrift, wasted his stores of useful material, but more — he
has wasted the work of nature through thousands of years by the
foolish destruction of the forest cover, wresting from it the toil-
somely achieved victory over the soil. He ha-^ destroyed the
grasses and even all vestige of vegetation, and has handed over
the naked soil to the action of wind and water. As the fertility and
agriculture of the plain is dependent upon the regular and
eijuable flow of water from the mountains, such as a forest
cover alone can secure, he has by barring the slopes accom-
plished in many localities utter ruin to himself, and turned them
back into inhospitable deserts as they were first before the
struggle of the forest had made them inhabitable.

One would hardly believe that certain mountains in France
had ever seen a luxuriant forest growth, and could during his-
toric limes have been so utterly despoiled of their vegetal cover.
Yet axe, fire, and cattle have been most successful, and the con-
sequences have been felt not only in the mountains, but in the
valleys below. The waters in torrents have brought down the
soil and debris, covering out of sight the fertile fields of thou-
sarjds of toiling farmers. They themselves have brought this
ruin upon iliem on account of their ignorance of the relation of
forest cover to their occupation. Now, with infinite hard work
and ex|iendiiure of energy and money, the slow work of restor-
ing the lorest to its possession has begun. The first work is to take
care of the rain-waters, and by artificial breaks turn them from
rushing torrents over the bare surface into a .succession of gentle
runs and (alls by fascine and stone works. This work must be
begun at the very top ol the mountains, at the very source of
ihc evil, where the water receives its first momentum in the de-
scent to the valley. The fascines or wattles, laid across each
iivulet at more or less frequent distances from each other, and
fastened down fiy heavy stones, are made of live willows or
other readily sprouting species, which in course of time strike
root and become living barriers. The pockets behind these
breastworks gradually fill up, and the contour of the mountain-
si Ic is changed from an even and rapid descent into a series of
sieps with gentle fall, over which the formerly rushing waters,
giadually and without turbulence, find their way to llic valley
below. Where the incline is too steep, and higher breastworks
are necessary, they arc made of masonry, sometimes at great
expense. At the ba^e of these overflow dams an opening is left
(or the water to drain through, even aflcr ihc depression behind

the rampart has filled up with debris, and soil has washed dow i
from above. Then, when in this way the soil has come to rest
forest planting begins, and gradually the torrent is " drowne.'
in vegetation.'' Sometimes, where on a steep moun
tain-side the naked rock alone has been left, it be
comes necessary to carry in baskets the soil to the trenche
hewn in the rock, where the little seedlings may take their fir*
hold, until they are strong enough to fight their own battle an ;
make their own soil, gradully restoring the beneficent condition-
which nature had provided before the arrival of man and hi>
senseless, improvident, self-destructive greed. By the irrational
destruction of the forest, first for the supply of timber, then
through the careless use of fire, by the clearing for unsuitable
farm use, by excessive grazing of sheep and goat, the mountain
sides themselves are not only dev.Tstated and made useless, but
fertile farms for two hundred miles from the source of the evil
are ruined by the deposits of debris, and the population pauper
ised and driven from their homes. Many millions of dollars
have been and many more will have to be spent before these
regions become habitable again.

That we are working in this country towards the same con-
ditions is too well known to need rehearsnl. Go to the shores
of Lake Michigan, or visit the coast of New England, New
Jersey, Pennsylvania, down to the Gulf, and you can -sec the
destructive action of the shifting sands set loose by improvident
removal of the plant cover. Go to the Adirondacks, the high-
lands of Mississippi, or the eastern slopes of the Rocky Moun
tains, and aspects similar to those derived from France will meet
your view.

What the farmer has brought upon himself here by excessive-
clearing, the lumberer, prospector, miner, or hunter prepare^
in the farthest West hy reckless and purposeless use of fire
Burnt mojntain-sides, where no living thing can subsist in com
fort, cover not acres but hundreds of square miles in the westerii
country. While the first fire only deadens the trees or under-
mines their constitution, the second or third fire usually is
suflicient to kill what remain alive, and even to clean up the
fallen timber. That these bald spots are not more frequent
than they are, is only due to the short period of our endeavours
in disturbing the balance of nature.

But as our nation prides itself on the rapidity of its develop-
ment, exercising to the utmost our constructive energies, so do
we excel in destructive and wasteful energies and tendencies,
and we shall come to grief with our resources much sooner than
some of our happy-go-lucky friends would like to make us
believe. While these exhibitions of American vandalism are
beyond the proprieties of legitimate warfare, there is not much
more propriety or intelligence visible in the manner in which
we levy tribute from the forest for our legitimate needs.
Forests grow to be used, but there is a great diflerence between
intelligent and unintelligent use. Improvidence and ignorance
characterise the pre^ent methods of using the forest growth.
The value of it is not even known. Of the 425 or more species
which are represented in the forests, not more th;in forty or fifty
at the most are found in the markets. .-Mthough, to be sure,
many of the species are of but little or no economic value, the
number of the truly useful trees is probably twice or three
limes as great as that actually used. Ignorance as to the
true value of them keeps many from little more than
simply a strictly local use, or from their most fit employ-
ment. The story of the black walnut used for fence
rails or firewood is well known. Six years ago the red gum
or liquidambar, now a fashionable finishing material, was
despised. Ten years ago large hemlock trees were mouldering
in the woods after the bark h.ad been taken fur tanning pur-
poses because the value of the wood was unknown. Cypress
and Douglas spruce cannot yet overcome the i)rejudice of the
market. On the other hand, collonwood and tulip poplar, not
long ago among the de.s[)ised or only locally used, can hardly
now be furnished in sufficient quantities, and the long leaf pine,
which had been bled for turpentine, was considereil an inlerior 1
material, which, as has lately been shown, is nothing but an
unwarranted prejudice.

In a vague empirical way the choice of the useful has been
attempted, and only lately have we begun to systematically
study our forest resources, to determine the qualities and adapt-
abilities of our limbers, and to find out the conditions under
which they produce not only the largest amount but the best
quality of limber.

Vet in ano' her direction do the forest users act unintelligently

N"'

1310.

V( L.

I

December 6, 1894J

NATURE

141

As we have seen, most of our forest trees are of a social
l.aracter. With few exceptions, they keep company with
her kinds than their own ; they appear in mixed forests.
Hence, where certain specie-;, as the pines and spruces, become
gregarious, and form unmixed, pure forests, the axe of the
lumberer does not as a rule level the entire forest, but he selects
the kinds which he wishes to use — he culls the forest. At first
sight this would appear rather an advantage for the existence of
the forest. So it is from a botanic, geographic, or landscape
point of view, yet from an economic point it is exactly the
reverse — it is disastrous.

In the well managed forests of Germany the undeserving
^pecies are exterminated, and the most useful fostered, just as
'he agriculturist exterminates the weeds and cultivates the crop.
Not only is the forest there confined to those soils and locations
Aliich cannot be used to better advantage, or which require a
) irest cover in order to protect the soil against detrimental dis-
placement, but it is so managed as to become a more and more
valuable resource, a crop of increasing importance, under the
management of skilled foresters, of whom, in a late debate on
the floor of the Landtag of Prussia, it was said that "While
most other productive business has declined, the forest ad-
ministration has steadily improved and yielded increasing
revenues."

The battle of the forest in this country is now fought by man,

lie unintelligent and greedy carrying on a war of extermination,

. ithout the knowledge that victory may lead eventually to iheir

.vn destitution; the intelligent and provident trying I-- defend

le forest cover, and endeavouring to prevent its removal from

;ch lands as cannot serve a better purpose, and to restrict the

lie of the balance to such rational harvest of its material, with-

at injurious effects on soil and water conditions, as will insure

:i ever reproducing crop and a permanent national resource.

While man may study the geography of the earth as it exists,

jre is about the only opportunity for him to make geography,

J shape the surface conditions of the earth, and even to some

extent influence its climatic conditions.

The lecturer then referred to the Adirondacks in particular,
showing views of forest destruction by fire, water storage, and
lumbering, and claiming that they need especially conservative
: L-alment, because the soil itself theire is made by the forest, the
;tT covering the native rock formed at the rate of one foot
n 300 to 500 years by the decay of foliage and litter, and hence
ts loss by washing of the rains is practically irremediable.

lie showed the paramount interest which the State has in

maintaining favourable forest conditions, and claimed that the

rivaie owners, being naturally interested mostly in the timber

Illy, and not caring for the future generations or distant and

: lirect benefits to others, could not be expected to manage

- nservalively.

Let it not be overlooked, that the State is not only the

representative of communal interests as against individual

iteresls, but also of future interest as against the present ; the

I ivate interest is not sufficient to protect this class of lands;

•hat State ownership or, what is more objectionable and less

ettective. State supervision of private forest lands is indispens-

Me in those regions where the forest subserves other functions

I ui that of mere material supply.

Grant for once that the community is interested in the pre-

crvation of the forest cover and its rational use with proper

reijard to the maintenance of permanently beneficial conditions,

'i.it the community would suffer from a destructive policy in

lose watersheds, and you must come to the logical conclusion

. t the community alone can be expected to guard its interests,

lit the community, the State, must own and manage these

. ' lods.

This does not mean that the same should be kept in virgin

ndition and unused, that the timber should be left to rot, and

•J productive capacity of nature's forces be allowed to go to

iste, but that a conservative management be instituted, keep-

il; in view both the indirect and the direct benefits of the

rest cover, utilising the crop without detriment to the forest

jnditions.

This, to be sure, is not done by such rules of thumb as a

restriction to cutting trees of given diameter, nor can the legis-

i.itor prescribe to the forest how to grow. He cannot be

expected to legislate how many trees to cut, how many to

leave, or to lay down rules of technical forest management, any

more than he would attempt to prescribe the size of the pillars

-upporting the roof of the Capitol, or to legislate on the pro-

NO. 1310, VOL, 51]

portions of an arch. It requires the knowledge, the experience,
the skill of a professional, technically educated engineer, just
as an eflective manageinent of the forest requires the knowledge,
the experience, the skill of professional foresters, and may not
be left to the ignorance and carelessness of the wood-chopper.

May the wisdom of the people of New York, of their legis-
lators and executive officers, be equal to the difficuhies of
solving the problem as a business proposition, and settling it in a
common sense, business-like manner. May their intelligence
and business capacity at least equal that of other States and
nations, and forestall the disastrous consequences that follow
unavoidably from neutrality or improper partisanship in this
battle of the forest.

yi

THE RELATION OF ENERGY OF COMBINA-
TION TO ELECTRICAL ENERGY.

HE problem of directly converting the storedup energy of
coal into available electrical energy is one of great import-
ance ; and as a first attempt to perform this operation, the ex-
periments made by Dr. W. Borchers, of Duisburg, and which
he described before the first annual meeting of the Deutsche
Elektrochemische Gesellschaft, possess great interest. The
author in the first place produced an electric current by the
' ' combustion " of carbonic oxide gas. The original form of the
apparatus used consisted of a glass vessel divided into three
compartments by two glass plates which nearly reached to the
bottom of the vessel. In the two exterior compartments copper
tubes were placed, which served for the introduction of the car-
bonic oxide, while the middle compartment contained a bell-
shaped mass of carbon. This carbon bell constituted one plate
of the cell, and the oxygen was introduced by means of a tube
within this bell. As electrolyte the author uses an ammoniacal
or acid solution of cuprous chloride ; this liquid readily absorbs
both oxygen and carbonic oxide, and is therefore particularly well
suited to form the electrolyte in a gas battery in which these
gases are used. Coal gas which contains 5 per cent, of car-
bonic oxide was, alter the first experiments, used in place of
pure carbonic oxide. The copper tubes were weighed before
and after each experiment, and no decrease in their weight was
ever found. With such a cell working through an external
resistance of 01 ohm a current of o'5 ampere was obtained,
while with an external resistance of 50 ohms the difference of
potential between the terminals was o'4 volt.

With a cell in which the outer compartments were filled with
copper turnings, in order to increase the absorption of carbonic
oxide by exposing a greater surface, and by ujing coal gas in
place of pure carbonic oxide, a maximum current of o'64 am-
pere was obtained, and by increasing the external resistance a
maximum difference of potential of o'56 volt was maintained.
The E.M.F. obtained by calculation from the heat developed
in the combination of CO and O is f47 volts, so that in the
above experiment 27 per cent, of the energy of combination of
the fuel is converted into electrical energy. Since a solution
of cuprous chloride dissolves hydrocarbons, powdered coal was
tried in place of carbonic oxide, when a maximum current of
o'4 ampere and a maximum E.M.F. of o'3 volt were obtained.
The above E.M.F. (O'J) corresponds to about 15 per cent, of
the energy corre-ponding to the oxidation of carbon. In the
case of the coal-dust, even when the liquid was kept in motion,
there was always a considerable falling ofTin the current, while
the pollution of the electrolyte by the coal would quite prevent
its use. With the gases, however, there is no falHng oflfof the
E.M.F., and this pollution of the electrolyte does not occur.

UNIVERSITY AND EDUCATIONAL
INTELLIGENCE.

C.\Mi;R1dge. — Dr. R. D. Roberts has been appointed chief
secretary for the University Extension scheme, in the room of
Mr. A. Berry, who retires at the beginning of the Lent Term
1S95.

The General Board of Studies report in favour of steps being
taken to establish a closer connection between .\ddtncirooke's
Hospital' and the University teachers in the departments of
medicine, surgery, and therapeutics.

The Syndics for State Medicine report that in the past year
fifty-six candidates presented themselves for examination in this

142

NATURE

[December 6, 1894

subject ; of these thirty-tno received the University's diploma
in Public Health.

Mr. H. Vule Oldhim, Uuiversi'y Lecturer in Geography,
has been admitted by incorporation to the degree of M..\.

The i'nivenity Reporter of Decembers contains a full report
of the speeches delivered at a meeting in King's College for the
purpose of promoting the foundation of a memorial library of
Oriental literature in honour of the late Prof. Robertson Smith,
editor of the Encydop^idia Brilnnnica.

SCIENTIFIC SERIAL.

Ariuri.ati Melioroh^i\a! yoiirna/, November. — Cyclonic pre-
cipitation in New England, by Prof. W. Upton. A list of
cyclones was made out, including nearly all in which the pre-
cipitation had been general over New England, and the amounts
and distribution noted on maps, with regard to the track of
the minimum pressure. The velocity with which the storms
passed r.^nged from fifteen to sixty miles per hour. The tables
show that the heaviest rainfall is rarely found along the central
path of the storm. Of the cyclones which came from the west
atross New England, only ten out of sixty-nine had their heaviest
precipitation on or nearthe storm-path, while forty-five had the
maximum area on the right of the storm-track ; similarly, out
of eighty-four cyclones which moved from the west mar New
England, seventy-three had their maximum precipitation south
of the storm-track. Further comments are reserved until the
results of a study of the storms coming from the south are given.
— The barometer at sea, by T. S. O'l.ear)'. This paper deals
with observations made chiefly by captains of American vessels.
The author considers that a great step forward was made when
the number of observations was reduced from twelve to one
daily, the result being that the number of observers has increased
nearly eight-fold. Another valuable feature is that the leaves
of the log-books are forwarded to the central office as soon as
opportunities are offered, so that the captains can see their
observations made use of without delay. A simple plan for
obtaining comparisons of the barometers has been adopted with
very satisfactory results. The observers when in port record
readings at certain hours, and forward them on post-cards to the
central office ; a copy of the "corrections" is immediately
returned to them, and copies filed for use and future reference.

SOCIETIES AND ACADEMIES.
London.

Royal Society, November 15. — "The Pigments of the
Pieridie. A Contribution to the Study of Excretory Substances
which function in Ornament." ByF. Gowland Hopkins.

The wing-scalesof the white Pieridx are shown to contain uric
acid, this substance practically actingasa white pigment in these
insects. A yellow pigment, widely distributed in the group, is
shown to be a derivative of uric acid, and its artificial production
as a bycproduct of the hydrolysis of uric acid is demonstrated.
That this yellow pigment is an ordinary excretory product of
the animal is indicated by the fact that an identical subst.nnce is
voided from the rectum on emergence from the pupa.

These excretory pigments, » hich have well-marked reactions,
are apparcnily confined to the Pieiidjc, and are not found in
other Rhopalocera. This fact enables the observation to be
made that when a pierid mimics an insect belonging to another
group, the pigments of the mimicked and mimicking insects,
respectively, arc cliemic.illy quite distinct.

Other pigments existing, not in the scales, but between the
wing membranes, are described, and are ■'hown sometimes to
function in ornament. The analysis, and the properties of the
yellow scale pigment are fully discussed in the paper.

Physical Society, November 23. — Prof. Riicker, F.R S.,
President, in the chair. — Mr. Womack read a paper on a
modification nf the li.illistic galvanometer method of determin-
ing the electromagnetic capacity of a condenser. The con-
denser is placed in parallel with one arm (.S) of a Whcalstone's
bridge arrangement of non-inductive resistances. A balance
for st?.vly currents having been obtained, the condtnser is
placed in circuit, and the throw on depressing the battery key
determined. The condenser is then thrown out of circuit, and

NO. I 3 ID, VOL. 51]

the proportionality of the arms of the bridge disturbed by
changing the value of S to S -F i/S. The steady deflection
due to this change is then read. From these two reading*; and
the known values of S and ./S the capacity is immediately
determined. In practice readings of dttlection may be taken
with equal positive and negative values of ./S. To avoid
changes of E.M F. of the battery, the author finds it best to
use a reversing key in the battery circuit, and to observe the
throw on reversing the current instead of on simply breaking
it. One advantage of the method is that there is no need to
know the galvanometer- or battery-resistance, and the author
points out that it may be of service in the simultaneous deter-
mination of the resistance and of the joint capacity and
inductance of a submarine cable or of a telephone or telegraph
line. Prof. Perry asked what were the .idvantages of the
method as compared with the Rayleigh-Sumpner method.
Mr. Bl.ikesley thought that the correction for damping in the
ballistic part of the experiment might be avoided if in the
second part the disturbance of balance due to the incremen'.
</3 were measured by half the first throw of the needle oninakini;
the galvanometer circuit, instead of by the steady deflection. He
doubted whether reversing the current in the battery circuit
would have just twice the effect of simply breaking the circuit.
In reply, Mr. Womack said he had not tried the method of
reading suggested by Mr. Blakesley, but with regard to the re-
versing of the battery circuit, that w.as found to give in practice
as nearly as possible twice the deflection which resulted from
simply breaking. — .\ paper, by Prof. S. P. Thcmp^on and Mr.
Miles Walker, on mirrors of magnetism, was re.id by Prof
Thompson. It was pointed out that, corresponding to the theory
of electric images produced by insulated conductors, there is a
theory of magnetic im,iges produced by bodies of infinite mag-
netic permeability. A magnet pole in the latter theory is the
analogue of an electric charge in the former, and a body of in-
finite magnetic permeability is the analogue of an insulated con-
ductor (which is electrostatically indistinguishable from a body
of infinite dielectric capacity). Experiments were made to de-
termine how far the magnetic images due to thick sheets of iron
accorded with those deduced by theory for the case of infinite
permeability. The image of a north pole in an infinite plane
sheet should consist of a south pole of the same strength at a
point coinciding with the optical image of the north pole, to-
gether with an equal north pole distributed uniformly over the
surface of the infinite sheet, as a free electrical charge would be,
and so exerting no finite action. Working at distances of a
few inches in front of the surface, a sheet of iron a few feet in
length and breadth, and a couple of inches thick, was found to
realise the theoretical conditions with very tolerable exactness.
In a coil of wire placed on one side of the sheet a current was
started or stopped, and the electromotive impulse produced in a
subsidiary exploring coil was detected by means of a ballistic
galvanometer. That the eflect of the actual mirror
was equivalent to that of the theoretical image, was
verified by substituting for the iron a coil equal
and similar to the first, and coinciding wiih its optical
image. Sending the same primary current as before round
the two coils (with due regard to its direction in the second coil),
hardly any appreciable difference in the secondary impulse w.as
observed. This was found to hold good whether the original
primary coil had its axis peipcndicular or oblique to the plane
of the magnetic mirror. Some observations on spherical sheets
were also recorded, but in this case the conclusions were less
simple. The paper was followed by a discussion, in which Mr.
Boys, Prof. Petry, Prof. Ayrton, Dr. Burton, Mr. W. Bailey,
and Prof. Carey Foster took part. — Prof. Ayrton exhibited a
student's apparatus for verifying Ohm's law, designed by him-
self and Mr. Mather. The current flowing through a circuit is
to be measured (not necessarily in terms of any defined unit) by
means of a galvanomclc-r, while the potential. diflerence between
two fixed points is measured by means of an idioslatic electro,
meter. Within small limits of experimental error, the current
and potential-dilTerence ore found to vary in the same pro-
portion ; but the electrometer and its manner of use constituted
the chief interest of the paper. The fixed and moving parts
(inductors and needle^i are alike cylindrical inform (the term
being understood in its most unrestricted sense), and the
generating lines are vertical. There is a vertical axis of sym-
metry, .such that the disposition of these cylindrical parts would
remain unchanged if the instrument were rotated through 180*
about the axis. The needle is hung by a very thin phosphor-

December 6, 1894J

NATURE

143

bronze strip, and to obtain a reading when it differs in potential
from the inHuctors by an amount which we have to measure, it
is brought back to its ordinary zero position by turning a torsion-
head to which the upper end of the suspending strip is fixed.
The potential difference is then proportional to the square root
of the angle through which the torsion-head has been turned, but
the E.M.F. of a moderate battery of accu-inilators can be read
with very fair accuracy. The authors have bestowed great care
on the design of the needle, so that, fur a given potential-
difference, the turning-moment divided by the moment of inerti.i
may be as great as possible. The whole instrument is pro-
tected from external inductive influence by having the inner
surface of its glass case coated with a transparent conducting
varnish, which Prof. Ayrton has described elsewhere. — Prof.
Ayrton also showed an idiostatic electrometer, whose needle,
instead of being suspended, was pivoted on an axle. The
instrument is rapid and nearly dead-beat in action, and gives a
scale-reading of about three inches for an E.M.F. of too volts.
Prof. S. P. Thompson expressed great admiration for the
instruments exhibited, but denied that the law which they
served to prove was Ohm's law at all ; and this led to some dis-
■cussion as to what Ohm's law really is. Prof. Ayrton briefly
replied.

Chemical Society, November l. — Dr. Armstrong, Presi-
dent, in the chair. — The following papers were read : The
electromotive force of alloys in a voltaic cell, by .\. P. Laurie. —
Determinations of the E.M.F. developed by sixteen alloys of
the heavy metals confirm Malthiessen's conclusion that the tin-
gold alloy is the only definite compound amongst them. — A
product of the action of nitric oxide on sodium ethylate, by
G. W. MacDonald, and O. Masson. Nitric oxide is absorbed
by an alcoholic solution of sodium ethylate with formation of
an explosive salt, probably the sodium salt of methylenedihy-
droxynitrosamine, CH2[N(NO)OH]„. The incomplete com-
bustion of some gaseous carbon compounds, by W. A. Bone
and J. C. Cain. When a hydrocarbon containing n atoms of
carbon is burnt with n atoms of oxygen, the interaction may
be represented by the following equation : C„Hv + 0„ =

»C0 -f - Hj, — Derivatives of tetramethylene, by W. H.

Perkin, jun. A number of halogen and hydroxy-deri-
vatives of tetramethylene and tetramethylenedicarboxylic
acid are described. Pentamethylenedicarboxylic acid,

CH

.CHj. CH.COOH

, by E. Haworth and W. H. Perkin,

"\cHj. CH.COOH

jun. A number of derivatives of this acid are described. —
Substituted pimelic acids, by A. W. Crossley and W. H.
Perkin, jun. The authors have succeeded in preparing ethyl-
and methylethyl-pimelic acid, and also describe several other
new aliphatic acids. — Homologues of butanetetracarboxylic
acid and of adipic acid, by B. Lean. The disodio-
derivative of ethylic butanetetracarboxylate reacts readily with
the alkylic iodides or chlorides yielding derivatives which on
hydrolysis are converted into tetracarbo.xylic acids of the
constitution, CR(COOII)„ . CHo . CH, . CR(COOH)2; on
heating these acids, di-substituted adipic'acids are obtained. —
Contributions to the chemistry of cellulose. (l) Cellulose
sulphuric acid, and the products of its hydrolysis, by A. L.
Stern. Cellulose disulphuric acid, CgH^OatHSOj)™, is obtained
by dissolving cellulose in sulphuric acid ; on hydrolysis, it yields
first cellulose monosulphuric acid, and then products containing
less sulphur.— The chlorination of aniline, by J. J. Sud-
borough. —Condensation of benzil with ethyl malonate, by
F. R. Japp and W. B. Davidson. Benzil and ethylic malonate
condense yielding monoelhylic benzoinylmalonate COPh.
CPh(OH).CH(COOH)COOEt, and desylenemalonic acid
COPh. GPh:C(COOHV

Linnean Society, November 15.— Mr. C. B. Clarke,
F.R.S., President, in the chair.— Mr. J. E. S. Moore exhibited
preparations illustrative of his investigations concerning the
origin and nature of the achromatic spindle in the sperma-
tocytes of elasmobranch fishes. I lis results were approximately
in agreement with those arrived at by Hermann in regard to the
corresponding elements in amphibia, and more in accord with
those of Ishikawa relating to the division of noctiluca. As to
the spindle fibres themselves, it appeared that during the diastral
Stage of the division they were the optical expression of thick-
enings in the wall of a membranous cylinder stretched out

NO. 13 10, VOL. 51]

between the chromosomes. — The Rev. G. Henslow exhibited
some curious iron implements of somewhat varied pattern, used
in Egypt for cutting off the top of the Alexandrine fig, ficus
Sycamorus, Linn., the operation being necessary to render it
edible by getting rid of the parasitic insect Synofhaga eyas-
fipcs, Westwood, with which it is always infested. The prac-
tice was said to be very ancient, being described by Theo-
phrasles, and alluded to by the same word, KVi^aiv, in the
septuagint version of the Old Testament (Amos vii. 14) in
translating from the Hebrew.— Mr. H. N. Ridley showed some
drawings of the green larva of a sphinx moth mimicking a green
tree snake, Trimeresiiriis IVayleri, as well as a cluster of cater-
pillars mimicking a fruit, all of which were found in Singapore.
He also exhibited a drawing from life of the tan-producing
gimbir-plant (Ciicaria Gambir) in flower. — Mr. Thomas Christy
exhibited some germinating seeds of pepper showing the testa
being carried up by the cotyledons. — A paper was then read
by Dr. D. Prain, on the plant-yielding Bhang Cannabis saliva.
Illustrating by lantern slides the anatomy of flower and fruit in
Cannabis, he reviewed the theories propounded of theirstruc-
ture ; confirmed from teratology those of Payer (1857) and
Celakovsky (1S75), and refuted those of B. Clarke (1853)
and Macchiati (1889). He then explained (1) the preven-
tion of fertilisation for development of narcotic properties,
and (2) of the various forms of the narcotic to each other.
.\ series of monoKious conditions described in plants of both
sexes show that the so-called i flower is probably an inflores-
cence, the perianth segments being bracts, not sepals, while the
stamen is the homologue of the anterior sterile carpel of the 9
flower. — A paper, on the proposed revision of the British
Copepoda, by Mr. Thornas Scott, was, in the unavoidable
absence of the author, read by the secretary.

Geological Society, November 21.— Dr. Henry Wood-
ward, F.R.S., President, in the chair. — The Pleistocene
beds of the Maltese Islands, by John H. Cooke. An especi-
ally noticeable feature of these beds is the absence of ordinary
anticlinal and synclinal folding, and the predominance of mono-
clinal faults, which largely affect the character of the surface.
These faults were formed prior to the deposition of the Pleisto-
cene beds. The plateaux of Malta, rising to a height of 600-
Soo feet above sea-level, occur south of the great east-and-west
fault, which has a downthrow to the north. They have no
Pleistocene deposits upon their summits. Three classes of
superficial deposits were described, namely : ( i ) Valley-deposits ;
(2.) agglomerates and breccias found along coast-lines and
fault-terraces, alwaje at the foot of the fault-terraces, or along
the lower slopes of the depressed areas ; (3) ossiferous de-
posits of caves and fissures. — Geological notes of a journey in
Madagascar, by the Rev. R. Baron. — On a collection of fossils
from Madagascar obtained by the Rev. R. Baron, by R. BuUen
Newton.

Mineralogical Society, — Anniversary meeting, November
20.— Prof. N. S. Maskelyne, F. R.,S., President, in the chair —
The annual report of Council was read and adopted. — The
following were elected ordinary members of Council : Prof.
A. H. Green, F.R.S., Mr. A. Harker, Mr. A. E. Tutton, and
Mr. W. W. Watts, in place of the four retiring members; in
other respects the list of officers and Council remains unchanged.
The following papers were read ; On cone-in-cone structure,
by the Rev. Prof. T. G. Bonney, F.R.S. ; confirming and
extending the views previously published by Prof. Cole.— On a
basic ferric sulphate from Parys Mount, Anglesey, by Prof.
A. H. Church, F.R.S. ; containing the analysis of an earthy
mineral corresponding to a compound of one molecule of
coquimbite with five molecules of normal ferric hydrate.—
Augelite, by Mr. G. T. Prior and Mr. L. J. Spencer ; contain-
ing a full account of the|chemical, physical and crystallographical
characters of specimens fiom Machacamarca, Bolivia, of a
mineral previously described only from massive material found
in Sweden. — On the occurrence of delessite in Cantyre, by
Prof. M. F. Heddle and Mr. J. S. Thomson ; containing two
analyses of the mineral. — Specimens of augelite, and of a
beautiful opal cast of a bivalve from Australia, were exhibited.

Paris.
Academy of Sciences, November 26.— M. Loewy in the
chair. —Photographic studies of some parts of the lunar surface,
by M M. Loewy and Puiseux. The need of care in interpreting
photographs takemi under ordinary conditions is emphasised ;
the many ways in which accidental circumstances may produce

144

NATURE

[DhCEMiJER 6, 1894

markings in the photographic film corresponding to no real
object render it essential that the more obscure details shall be
fully confirmed by a close correspondence in form and extent on
different negatives. Again, the tendency to aggregation of the
reduced silver in the negative destroys all value in enlarge-
ments carried beyond a certain limit, say thirty or forty
times the original size. Certain clear negatives, obtained at
Paris on February 13 and March 14, have been enlarged by
Dr Weinek and compared with the best maps of the corre-
sponding region, with the result that many new details, fully
described in the paper, have been added to our knowledge of
the moon's surface.— .\ note on the calculation of the orbits of
planets, by M. F. Tisserand.— -■^n observation of Wolf s planet
(1S94, BE), made with the Bordeaux equatori.-il, by *•• G.
Raye,'_On the laws of air resistance, by M. E. \allier.
Formula are derived which express the specific resistance of
air to a moving body {a) where the velocity is greater than
^',0 metres. (/') where the velocity is between 330 and 100
metres, and (c) where the velocity is less than 100 metres per
second.— New details concerning the Nympha'in;^ ; tertiary
NvmphxinK.by M.G. de Saporta.— The elements of the planet
BE by M L. Schulhof.— Observations of Swift's new comet
E (1S94 November 20^ from the Paris Observatory, by
M G Bigourdan.— On the distribution of planets between
Mars and Jupiter, by >I. E. Roger. .\ mathematical paper
in which the author endeavours to obtain, from the known
distribution of the minor planets, some support for a hypothesis
formulated in a previous communication {Comples-rendus,
t. cxvi. ).— On the movement of a solid body, by M. G. Kojnigs.
—On an application of the principle of areas, by M. L.
Lecomn.— On functional equations, by M. Leau.— On Ber-
trand's theorem, by M. Cartan.— .\ rklavtation concerning
M. P. Siiickel's note' on the problems of dynamics of which
the differential equations admit an infinitesimal transformation.
M. Quo Staude published a paper on this subject in 1S92. M.
Stackel merely extended the theorems therein demonstrated
from I wo and three to « variables.— On the tempest of November
12 1S94, by M. .\lfred Angot. A tabular comparison is made
between data obtained at the Meteorological Bureau and on the
Eiffel Tower respectively. Interesting conclusions are drawn
from the tower observations, which are free from the disturb-
ances ordinarily brought in owing to the nearness of the surface
of the soil —On the conversion of propionic acid into lactic
acid, by M. Fernand Gaud. By healing a mixture of 10 per
ceni of propyl alcohol with Fehling's solution for 200 hours at
240°, the author has obtained both the ordinary and isomeric ^
lactic acids. .\s metallic copper is produced on hciting copper
propionate with excess of water at 200°, the equation repre-
senting the production of the lactic acid must be written
2(C,H,0.). L'u -h 2H,0 = 2Cu + ^C^H.O^ -i- 2C3H6O..-
On the ethereal salts derived from active amyl alcohol, by M.M. |
Ph. A. Guve and L. Chavanne. The specific rotations
are given for a number of these esters, the maximum value is
obtained for the fatly salts with amyl propionate. The product of
asymmetry reaches its maximum with amyl acetate.— On the
!to-callcd organic chlorine of the gastric juice, by M. H.
Lescocur. A direct method of determining organic chlorine
is described, and it is pointed out that the ori^anic chlorine of
MM. Ilayem and Winter is partly derived Irom ammonium
chloride, which is if.elf partly formed at a high lemperature
from the sodium chloride present.— On the composition of
the red pigment from Viemyctylui firiJesieiii, by M. A. B.
Griffiths The analytical results give the formula C,„H„N;U-
for die.nyctyline.— On acid leathers, by MM. Ballaiid and
Maljean.— A new cnloptical phenomenon, by M. S. Tchiriew.—
The principles of chroology or physiological synthesis of colour,
bvM. W. Nicati.— On the effects of ablation of the venom-
Rlandt in the viper ( ('//^ni .Upis, Linn.), by MM. C. Phisalix
and G. Bertrand.— Contributions to the study uf the cellule
conjonctive" in the molluscous Gasteropods, by M.Joannes
Chalin.— Anew method for the cultivation offish-ponds, by M.
Jouisel de Bellesme.— The reptiles of the upper Jurassic age in
the Boulonnais, by M. II. E. Sauvage,— On the new ivory
human matuelles from the quaternary station at Brassempouy,
by M. Ed. Piette.— Influence of arsenic acid on the growth of
alga: by M. Raoul Bouilhac. It is shown that arsenic acid in
certain cases acts like phosphoric acid, which it may replace in
•omc plant cultivations. -On the age of Lake Bourget and the
ancient alluvial deposits of Chamber/ and the valley of the
Iscrc, by .M. .\. Dclebecque.

BOOKS, PAMPHLETS, and SERIALS RECEIVED

BoOiC^ -The Province of South .\ustrali.i t J. D. Woods (.\delaije, Bri.~-
tow).— fh<^ Mechanism of Weaving: T. W. Fox (Macmillan).— Meteor-
oloKV, Practical and .Applied: Dr. J. W. Moore (Rebman) — Life of
Richard 0«en: Rev. R. 0«en. i' Vols. (Murray).-tlc,nems of Astro-
nomy : G. W. Parker (Longmans).— .\ H»nd-book -to the Order Lep.dop-
.era. Pan 1. Butterflies, Vol. . : W. F. K.rby (.\Iien).--.\ H.and-book 10
the Primates: Dr. H. O. Forbes. 3 Vols. (.Allen).— Ostwald s klassiker der
Exakren Wi>sen>chaften : Nos. 54-5y (Lt'PziK. Engelm.alin) — Physikal-
ische Kr^■staIl0l!taphie: P. Groth. Dritte .Auflaae. I .ind i Abth?. (Ulpzig
En'clm.innl- Grundii^sder P^vcholog.e : O. kiilpe (Leipzig. Engelmann)
-Portraits beruhmter Naturforscher (Wien, Richler).-Ihe Iron-bcirms
Kockscf the Me,>abi R.aoge in Minnesota: J. E. Spurr (Minneapo is).—
Coal Deposits of Iowa : C. K. Keyes (Des Moines).— I .S-Oeologicil Sur
vey. Twelfth Annual Rtporl. i5.>o-9i. Part i, Geology ; Part 2 Iirigation
(WashiDgton),-Ditto.Thirtcenth Annual Report. Part i, Report of Director :
Part 2 Geology: Part ^, Irrigation (W ashington).— N Z. P.ipers and
Reports relating to Minerals and Mining (\Ve,lington).-An.maire de
I'Observatoire Municipal de .Montsouris, 1S93 (Pans, Gauthier-% lllars).-
Kitchen-Boiler ExpK.<ions: R. D. Monro (t^fhn), -The Llememary
Properties ol the Elliptic Functions: Prof. .A. C. Dixon (Macmillan).-
Birds of the Wave and Woodland: P. Robmson (Isblster).— Llementary
Commercial Geography: Dr. H. R. Mill, 2nd edjiion (Cambridge Un,.
versity Press).— An Inttodiiciion to the Theory of Electricity . L. Cum-
ming. 4th edition (Macmillan).-SymbDlic Logic : Or ). Venn, 2nd ediiioi,
(Macmillan).— Farm Vermin, edited by T. Watson (Rider).— The Cyclo-
paedia of Names : edited by B. E. Smith (L nwin).

Pamphlets. -Geological and Natural Hisory of Minnesota : N. H-
Winchell (Minneapolis).-Magnetic Observ.a,ions nuiJe at^^he U£_N^^
Obsen-atory durmg ihe\car iSja*. Frof. b.J.

Brown (Washington). ■

Me7.Vrolog1cal Observations and Results. IJ.S. Naval Observatory, .83,
(Washington). -The Warble Fly : E. A. Ormerod (S.mpkm) -Amer.can
Museum of Natural History, .Annual Report for 1893 (New \Ork).

Sekial:

-Archiv fur Entwickelungsmechanik der Organismen : Prof. W.
■ '^ ' n). — Studies from the

Roux^ ErsterBand. Erstes Heft (Leip/ig, EngelmannJ.-Studies from th
Y-tle Psychological Labora.or;-, Vol.2 (New Havenl.-BiologyrNotes, Nos.

' 1 .^^ . F 1. I, ii_.:_ „f .1 — A ........--in MatKi-niaftr.il Soi-letv. 20

nd -VChelmifordj.-Burieirnof the American Mathematical Society
""-^x . .. .kr ,-.^1. *f :n.,«\ — '^.-K^ol Review, No

nd
series Vol i. No'.'j (NewVork, M.icmillan). -School Review, November
(H.amilton, New York).-Journal oj; the College_o(^Scie_nce, Imp^^^

;^"t^'^g;;ar;;;i7^Iou™::i"iV MicrilcJi^cal- Science. NoOeii^r
ChurchillX-Forlnightly Review. December (Chapmar,).-Morpho ogischen
lahrbuch 22 Band. . Heft (Leipzig, Engelmann).-Zeitschrifl fur Physikal-
Sie Chemie, XV. Band, 3 H.f. (Leipzig, Engelmann) -- N..t.onal Review,
December (Arnold). -Scriboer's Magaiine, December (Low).

CONTENTS. PAGE

Peculiarities of Psychical Research. By H. G.

Wells . . . „

The Beginnings of History ■ - ■ "

The Transmission of Power, by G. F iz4

Our Book Shelf: — , . j n ui-

Stevenson : "A Treatise on Hygiene and Public

Health" ; •. ■ • ' ',.' '.' .u. '^^

Kalpa : " Involution and Evolution according to tne

Philosophy of Cycles" -^ • • : „ '^^

Muir: "The Mountains of California '-^i

Letters to the Editor: —

Origin of Classes among the "Parasol" Anls.-

Herbert Spencer ■■■■„' i^

"Acqui.ed Characters.' -J. T. Cunningham; Prof.

Eaward B. Poulton, F.R.S ', • ' '^°

The Homing of Limpets -Prof. C. Lloyd Morgan .27

Gravitaiion.-Dr.J.Joly. F.R.S. ^ ■.■■■..■ '^^
The Ratio of the Specific Heats of Gases.— S». «-

Burbury, F.R.S. . . •■■••, 'J,

An Observation on Molhs.-^Henry Cecil . . . - 27

Snakes "Pbying 'Possum.' -G. E.Hadow . . . 127

Volcanic Stalactitef. (lllxstrauJ.) '^o

Notes

Our Astronomical Column :—

The New Comet ^^'

The Spectrum of Mars • ; • ■ • • ', i " :!,„ ' ' ,^2

The Anni'versary Meeting of the Rtjyal Society . .3'

The Battle of the Forests. H. By Prof. B. E. ^^^

The^ReUtUin of Energy of Combination to Elec- ^^^

University VndEducationkllntelligence Ut

Scientific Serial j

Societies and Academies . . • ■ •. , , .

Books, Pamphlets, and Serials Received 144

NO. I 3 10, VOL. 51I

NA TURE

145

THURSDAY, DECEMBER 13, 1894.

DILETTANTISM AND STATISTICS.
The Gro-i'th of St. Louis Children. By William Town-
send Porter. Vol. vi. No 12 : Transactions of the
Academy of Science of St. Louis.

THE anthropometrical researches of Mr. Francis
Gallon have had a very widespread influence, and,
under his inspiration, a large mass of material has been,
and is being collected, which cannot fail to be of
service in elucidating a number of knotty problems. In
particular, very comprehensive measurements of children
have been made in America by Bowditch, Sargant, and
Porter, the results being tabulated by aid of Mr. Galton's
method of percentiles.

It is not only in the form of statistics of measurements
on man, but also of measurements on the lower animals
and on plants, that material for the study of variation
and correlation is accumulating with almos'. alarm-
ing rapidity. VVe say with almost alarming rapidity,
for not only is theory lagging somewhat behind the
needs of statistical experience, but, what is far
worse, many collectors have no real insight into the
theory which does e.xist. They are tabulating results in
a form which will be of no permanent service, or neglect-
ing to publish the very details which alone would enable
us to test any development of statistical theory. The
ignorance of the elements of mathematics, to say nothing
of the theory of chance, is, indeed, singularly character-
istic of many investigators, who think statistics can be
handled, and conclusions drawn from them, without the
least preliminary training. For e.xample, in a recent
paper on variation in the flowers of buttercups and
clover, by Herr de \'ries, we are introduced to our old
friend the normal curve of errors as a definite sym-
metrical polygon ; no attempt is made to fit it by aid of
the probable error of the observations, but a particular
form of it, apparently selected at random., is plumped
down on the top of another polygon representing the
observations. The odds against the thus selected
theoretical polygon (curiously called the " Galton Curve ")
expressing the real distribution of variation, are, it is need-
less to say, many thousands to one. Still more curiously,
sets of observations giving theoretically very good fre-
quency curves of the type which occurs in infantile
mortality, the valuation of houses, &c., are termed
" Half-Galton-Curves," although the type, so far from
being represented by the half of the normal curve of
errors, corresponds to a curve asymptotic to the ordinate
of maximum frequency ! We might pass these eccen-
tricities by, were not statistics thus handled used to
support some vague theory of heredity, or to question
some principle of variation.

Mr. Porter is not quite so wild in theory as Herr
de Vries, but for him also the normal curve of errors
appears to be a polygon, and he tells us, on p. 277, after
a table of its ordinates — which are quoted from Thoma,
and given only to the units, and not to decimals — " that
there is a limit beyond wkici; no deviation occurs." It is,
perhaps, needless to say that if we start only with a know-
ledge of the theory of chance, such as may be found in
NO. 1311, VOL. 51J

works like those of Thoma and Stieda, we are hardly
likely to avoid bad theoretical blunders. Mr. Porter
is no worse than many writers of memoirs in the Toiirnal
of the Royal Statistical Society; but the time has come
when statistics, as well as archaeology, must be taken
out of the hands of the dilettanti, and when a man, if
he takes upon himself to publish statistical researches,
must, like the physicist, show his credentials in the form
of a fair mathematical training.

Unfortunately, Mr. Galton's method of percentiles,
useful as it is in the right place, is now acting as a
distinct check to statistical theory in a somewhat un-
expected manner. Before that theory was disseminated
the dilettante statistician was compelled to publish his raw
material, and his remarks on it did not impair its value
to the trained scientist. Now, however, the percentile
method of dealing with statistics seems so intelligible,
that the non-mathematical anthropologist or physiologist
grasps it at once, reserves his raw material, and pub-
lishes tables of percentiles. It is hard to conceive any-
thing more disastrous for true statistical progress.

The reason for this is easily explained. As is well
known, any normal curve of errors can be reduced to any
other by uniform stretches (or squeezes) parallel to its
base and its axis. The area of any portion of any normal
curve up to a deviation of given magnitude cannot be
given by a finite series ; it can by stretching be reduced
to an integral, the values of which are tabulated, but
which is not itself finitely expressible for an indefinite
value of the deviation. The tables formed of this in-
tegral, however, enable us to pass from selected percen-
tiles to the constants, and so to the form of the frequency
curve. Now, innumerable frequen cy curves in biological,
just as in economical statistics, are »<•/ of the normal type.
.•\ generalised frequency curve can be theoretically ob-
tained fitting closely the observations in many, perhaps in
all such cases, but owing to its asymmetry or skewness, its
limited range and other features, it neither possesses the
stretch property of the normal curve, nor can its areas
be expressed by tables of one entry. The tables required
are, according to the type, of two or three entries, and
such tables are not likely to be prepared for a long time
to come, and if prepared, would be of little service except
for the case when the statistics are given in percentiles. In
other words, the use of percentiles may suffice to demon-
strate the skewness of the statistics, but at once precludes
the use of any theory higher than that of the normal curve,
by which the skewness could be accounted for. This is the
fundamental defect of Mr. Porter's labours. He gives us a
most extensive system of measurement on boys and girls
from six to twenty years of age— ample material, if properly
dealt with, to provide solutions for innumerable problems
in correlation and selection with age. The material, how-
ever, is only given in the form of percentiles or in dia-
grams of the "ogive" curve corresponding to the integral
of the frequency curve. These diagrams fully confirm
the results of Bowditch— Ma/ the statistics are skew, and
that the degree of sxe'u'ness varies -ujith the age. But all
means of scientifically treating this skewness disappear,
because we have only percentile results. The skewness
of theoriginal frequency curve cannot be deduced from nine
or ten points on a curve, the equation of which is only
expressible by an unintegratable form containing the con-

H

146

NATURE

[December 13, 1894

scants to be determined. This is all the more tantalising,
as the variation with age (or with selection) of the
skewness of the frequency curve for a given organ is
verj- probably a most important factor in the mathe-
matical treatment of evolution, while it is precisely
human material which enables us to record the
age, too often an unknown quantity in investiga-
tions on the lower animals. It must not be sup-
posed, however, that Mr. Porter realises that skew-
ness in the percentiles marks want of normality in the
frequency curve. On the contrary, he takes the raw
material for the height of 2192 girls aged eight, and fits
it, not very accurately, to a normal frequency distribution.
Although the measurements better fit a skew than a
normal distribution, the divergence from the normal is
not very marked, and Mr. Porter writes :

" It is not necessary to make this comparison at more
than one age, or in more than one dimension, for it is
known that if one series in a group like that with which
we have to deal shows this agreement, the other series
will be found to do the same." (p. 290.)

Now the whole point of the measurements, if properly
interpreted, is to ascertain the varying degree of skew-
ness with age, i.e. the varying amount of divergence
from the normal curve. To emphasise this divergence
when remarking on his raw material, but to fail to
recognise what bearing it has on theory, is typical of the
untrained statistician.

As we have seen, the use of percentiles renders Mr.
Porter's material of small value for the problem of selec-
tion. The same remark again applies in the case of cor-
relation. The ten organs measured would have been
most valuable material for the problem of correlation ;
the percentile results alone being given, nothing can be
done. In Chapter ix. Mr. Porter does develop a theory
of correlation, which, however, seems to us absolutely
erroneous. As he makes it the basis of a scheme for
the school physician to testify whether the pupil's strength
is equal to the strain put upon it, this want of accurate
theoretical knowledge appears doubly unfortunate.

We have ventured to point out these failings in Mr.
Porter's work, not because they are peculiar to him —
they are characteristic of much work of a statistical
kind which is now being turned out in both Europe and
America — but rather because they point to a new need,
which the public has hardly yet recognised. There has been
up to the present time — with the honourable exception of
courses of lectures by iJr. X'enn in Cambridge — no teach-
ing of statistical theory in England. There is no chair
of statistics in any English university, and the Newmarch
lectureship at University College, except for the year of its
tenancy by Prof. Edgeworth, has been held by economists,
and not by mathematically trained statisticians. We
want a centre, which shall not only contain a statistical
museum, but embrace as well a statistical laboratory
and workshop. In such a centre students might not only
receive a mathematical training in dealing with raw
statistics, but also be exercised in the methods of
collecting and tabulating, which must precede mathe-
matical reduction. To such a centre the biologist and
anthropometrist could send their measurements to be
"fitted," the physicist his observations to be dealt with,
and the economist or sociologist his price or labour
NO. 131 I, VOL. 51]

statistics to be analysed. At the same time, absolute
measurements might be made bearing on the problems of
evolution, disease and national economy. In this manner
a number of efticient young statisticians might be trained,
who would not only find a life-work ready for them in
craniology, zoology, botany, and economics, but who,
passing into government departments, census offices and
labour bureaus, might remove from us the reproach of a
recent continental writer, that nowhere were statistical
dilettanti so rampant as in England.

Karl Pe.\rson.

WATER SUPPLY AND WATER-WORKS.
The Principles of Water-works Engineering. By J. H.

Tudsbery Turner and A. W. Brightmore. (London :

Spon, 1S93.)
The Water Supply of Towns. By \\. K. Burton.

(London: Crosby Lockwood and Son, 1894.)

WITH the constant growth of population, and the
increasing tendency of the population to con-
gregate into large towns, the provision of an ample
supply of pure water to towns becomes every year of
greater importance ; whilst, as the nearer sources of
supply become inadequate for the ever-growing demands,
a sufticient supply becomes more difficult to obtain, and
has to be sought at considerable distances. Accordingly,
the subject of water-supply has assumed an enhanced
importance within recent years ; and till these books
appeared, there was a dearth of comprehensive text-
books on this branch of engineering. As the sources of
water-supply, and the works for its provision and distri-
bution are comprised within very definite limits, both
books necessarily traverse much the same ground, and
deal with similar classes of works ; but, nevertheless,
they exhibit dili'erences in arrangement, and in the
method of treating the various subjects. Thus, whereas
'Water-works Engineering" extends over 420 pages,
separated into only eight chapters, and illustrated by one
hundred and twenty figures in the text, " The Water
Supply of Towns " is subdivided into twenty-two chapters,
occupying only 272 pages, somewhat larger in size, but
illustrated by two hundred and fifty-seven drawings,
several of which are put into forty-three large folding-
plates. The first book, moreover, is subdivided
into numbered sections, the numbers of which are
merely used for reference, and instead of the pages
in the index ; whilst the various subjects in the
second book are clearly indicated by black-letter
headings. Altogether, " The Water Supply of Towns "
is much better arranged for reference ; and though
containing slightly less matter, it is much more fully
illustrated, is in larger print, and has a somewhat longer
index than " Water-works Engineering." Neither book
gives a summary of contents at the head of each chapter,
which is often serviceable for reference.

In " Water-works Engineering," the sources, measure-
ment, collection, storage, purification, conveyance, and
distribution of water, and the maintenance of water-
works, are successively dealt with in the eight chapters.
The most logical sequence would be to describe in regular
order the various processes to which water is subjected,
from its source up to its delivery to the consumer.

December 13, 1^94]

NATURE

U7

This has only been partially accomplished in " Water-
works Engineering," for, owing to the small number of
chapters, such dissimilar subjects as the available rain-
fall and the gauging of the flow of streams have been put
in the same chapter, near the beginning of the book,
with water-meters, which latter subject should pro-
perly have been dealt with at the end, in connection
with consumption and waste. Moreover, impound-
ing reservoirs and dams are grouped with service
reservoirs, tanks, and house cisterns ; whilst the
filtration, purification, and softening of water, are con-
sidered before the preliminar)- process of conveyance
from the source of supply by aqueducts and conduits.
Though the grouping of dissimilar subjects has been
avoided in " The Water-Supply of Towns " by the
multiplication of chapters, the natural sequence of pro-
cesses has not been always maintained ; for the chapters
on pumping machinery, and the flow of water in conduits
and open channels, follow after the chapters on purifi-
cation ; whereas the flow of water is intimately connected
with the conveyance of the supply from impounding
reservoirs; and purification and softening are mote needed
for waters pumped out of rivers, or from wells, than
for waters impounded in a reservoir in a mountainous un-
inhabited district. In this book, however, the descriptions
of water-meters are given in the chapter on the prevention
of waste of water, to which subject they properly belong ;
and cisterns are referred to in this connection, as well as
in relation to distribution.

The most notable difference between these two books
consists in the use made of mathematical calculations
and formulx. Prof. Burton rarely introduces any
formulae, contenting himself, in the case of high masonry
dams, with diagrams of the theoretical profiles proposed
by Prof Rankine and Mr. Wergmann, in addition to the
actual sections of the Vyrnwy dam in Wales, and the
Tytam dam at Hong Kong ; whilst he refers his readers
to Fanning's " Treatise on Hydraulics and Water-works
Engineering " for formula; relating to the flow of water.
A less cursory treatment of these important subjects, in
relation to water-supply, might reasonably be expected in
a book which is stated, on its title-page, to be "a practical
treatise for the use of engineers and students of en-
gineering " ; but perhaps Prof. Burton exercised a wise
discretion in this matter, for in the calculation of the
cross-section of a stream, on page 28, he falls into an
obvious error in including the depths at both extremities
to obtain the average depth. The authors of "Water-
works Engineering," on the contrary, incline towards the
other extreme, and devote more attention to mathematical
solutions than to practical considerations. Some amount
of mathematical tre.itment is unquestionably expedient
in dealing with the flow of water and the design of
masonry dams ; and formula; based upon experience,
together with diagrams, furnish almost indispensable
aids in the consideration of these matters, and for their
practical application. It is, however, an undue extension
of the province of mathematics, in such a treatise, to use
them to prove that impalpably fine matter in suspension
in water would never fully settle (pp. 266-7), which is a
subject for physical experiment ; and the result would
vary with the nature of the material and its specific
gravity. Moreover, considering the uncertainties that
NO. 131 I, VOL. 51]

exist as to the precise distribution of the pressures over
the masonry of a reservoir dam, it appears somewhat
superfluous to devote over two pages in calculations
proving that wind pressure against the outer face of a
masonry dam has only a very slight influence in modi-
fying the position of the line of resultant pressures, with
the reservoir empty, under the e.xceptional conditions of
a high wind blowing up the valley, and the reservoir
being empty. The somewhat free use of mathematical
processes, and the occasional introduction of the integral
calculus, will unfortunately be liable to deter persons, who
have not received a regular mathematical training, from
consulting " Water-works Engineering " ; though the
greater part of the book deals clearly and concisely with
the practical matters and works relating to this branch of
engineering. More frequent references to executed works,
by way of illustration, would have added interest to the
book, and would have served to exhibit the methods of
application of general principles, and their results ; but
the authors explain in their preface, that they considered
descriptions of works outside the scope of their book.
Owing doubtless to their having lived in cities supplied
from wells and impounding reservoirs, they condemn the
quality of river waters in stronger terms than the inhabi-
tants of London, deriving a large proportion of their
supply from the Thames, would be prepared to admit as
correct. They say : " The quality of river- water is seldom
unexceptionable, and is frequently bad. . . . Rivers are
generally charged with impurities of vegetable, animal,
and mineral origin, to such an extent as to render them
frequently a most desirable source of water for irrigation
purposes, but not for domestic supply.'' .\fter this it is
only a slight consolation to be told that, " still, by certain
processes, even the most unpromising river-water is often
rendered generally serviceable," especially as, shortly
after, they quote the statement of the Rivers Pollution
Commission of 1S68, that "there is no river in the
United Kingdom long enough to effect the destruction
by oxidation of sewage put into it at its source," and
add, in conclusion, that " the result of the aeration pro-
duced by even the Falls of Niagara is so insignificant as
to be insensible so far as regards any purifying eft'ect
upon the water."

As the author of "The Water Supply of Towns'' is
Professor of Sanitary Engineering in the University of
Tokyo, he has naturally inserted some matters relating
more particularly to Japan, such as, for instance, certain
special provisions for the extinction of fires which are
very common in Japan, owing to the light construction
of the houses, and more especially the probable eflects
of earthquakes on water-works, and the precautions to
be taken against them. Most, however, of these special
matters have been relegated to foot-notes and an
appendix ; whilst some particulars of general interest
relating to the Tokyo water-works are given in the text.

Both books contain a fairly complete exposition of the
principles relating to the water supply of towns, and a
general description of the construction of water-works ;
and they should both prove valuable to the engineer and
the student, in relation to this special branch of engineer-
ing. Whilst, however, the engineering student, who has
had the advantage of a mathematical and scientific
training, will doubtless prefer the more scientific metho

uS

NATURE

[December 13, 1894

exhibited in " The Principles of Water-works Engineer-
ing," the practical engineer will obtain fuller information,
with less trouble, from the more clearly arranged and
better illustrated pages of " The Water Supply of Towns.''

HAMILTON'S PATHOLOGY.

A Text-book of Pathology, Systematic and Practical.
By D. J. Hamilton, M.B., F.R.C.S.E., F.R.S.E.,
Professor of Pathology, University of Aberdeen.
\'ol. ii. Parts i and 2. ;London: Macmillan and Co.,
1S94.)

THESE two handsome volumes complete the labor-
ious task which Prof. Hamilton set himself many
years ago, of producing a text-book of pathology, which
should include not merely morbid anatomy and histology,
but should deal also with clinical medicine, and those
new but rapidly developing sciences, pathological
chemistry, pathological physiology, and bacteriology.

It is true that the many varied problems which come
before a pathologist require for their solution a more or
less extensive acquaintance with each and all of these
branches. So many, however, are the workers, and so
vast has the literature become in each branch, that it is
already impossible for anyone to be equally proficient in
all. and it is necessary to specialise.

If this is the case with the individual, it is much more
so with the text-book. It is impossible to compress
within even 1800 pages, a tithe of our present knowledge
of all these branches, and opinions will differ widely as
to how the selection should be made.

The task of making such a selection is herculean
enough to daunt any man, and the thanks of all
interested in pathology are due to the Professor for the
very valuable addition he has made to our literature on
the subject. The amount of original work is considerable,
and the volumes are copiously illustrated by drawings,
the majority of which are by the author.

.\n extremely useful feature in the book consists in the
bibliography of both the English and foreign literature
at the end of each section. The convenient system is
also adopted of indicating the title of any publication
referred to in the text by a number in Roman letters,
while the full titles and the corresponding numbers are
given in a list at the end of the book. The first volume,
which was reviewed in these columns in 1SS9, met with
general appreciation. This volume commenced with full
directions for making systematic post-mortem inspections,
and for the practical bacteriology and histology of the
tissues removed. .Nearly 200 pages were devoted to
a full account of inflammation and suppuration, and of
tumours and new formations, while the remainder of the
book was occupied by an account of the heart, the blood,
and the vascular system generally.

The two parts of the second volume now issued are
bound up separately. The first part of the present
volume is devoted to a systematic account of the patho-
logy of the respiratory organs, the liver and the kidney ;
a good solid piece of work containing much original
research, in which arc embodied the well-known papers of
the author on diseases of the lungs, and on cirrhosis of
the liver. .Among the many observations, we would draw
attention to the important conclusion that in nephritis
NO. 131 I, VOL. 51]

the fatty granular remains of the convoluted epithelium
are absorbed by the lymphatic system, and are not, as is
generally supposed, mainly washed out by the urine.

The drawings, illustrating the author's views, are worthy
of all praise ; they are well executed, and are sufficiently
diagrammatic to impress the conclusion to be indicated,
while their reproduction also reflects great credit on the
publishers.

The remainder of the volume deals with the diseases
of the digestive, the nervous, the osseous and the
cutaneous systems, finishing with a short statement of
the various malformations, and a good summary of
systematic bacteriology and of human parasites.

The present volume is overweighted by 150 pages of
normal anatomy and physiology, which preface the
accounts of the various organs, nearly fifty pages and
twenty illustrations being devoted to the nervous system.
This material is surely out of place in a book, in which
the author has been compelled by the exigencies of space
and time to reduce his account of the pathology of many
conditions to too brief an account to be of value, so that
often there is no indication as to which lesions and
causes are common and important to remember, and
which are exceptional ; frequently a mere list of them is
given.

It is also to be regretted that it has been thought
desirable to devote valuable space to the description ol
the various tests for sugar and albumen in the urine, as
this information is contained in the ordinary standard
books on clinical medicine.

The author apologises for the lapse of five years since
the appearance of the first volume; and we cannot help
regretting that Prof. Hamilton did not publish only the
first part of the present volume, and allow himsell
another year or more in which to have worked up the
second part to the high standard reached in the earlier
portion of the book. Although five years may appear a
long time, for the production of the second volume of
this book, still the amount of labour required was so
extreme that more time was really necessary. The lack
of space also has necessitated so much compression, that
often the pathology is reduced to a mere explanation of
the terms used ; while the numerous omissions of im-
portant facts suggest that this part has been produced at
very high pressure, so that the facts are not presented in
their due relation to one another, while there are several
statements to which we would take exception.

While such common causes of optic neuritis as plum-
bism and aniumia are omitted, excessively rare ones, such
as pneumonia and measles, are given ; again, while optic
neuritis is discussed, optic atrophy is omitted. Among
the causes of cerebral h;emorrhage, such well-recognised
ones as glioma and aneurysm are omitted.

Through oversight the following conflicting statements
have been allowed to appear. Under cysts of the liver,
the association of such with similar ones in the kidney
is said to be fortuitous ; while under the head of
renal diseases, it is noted that out of sixty-two cases of
cystic kidneys, seventeen were associated with similar
cysts in the liver. On one page, in discussing the growth
of typhoid bacilli, great doubt is thrown on whether they
spore ; on the next page, it is stated that they invariably
spore when grown under suitable conditions.

December 13, 1894]

NA TURE

149

The excellence of the work, and it is great, lies in the
histological and bacteriological portions, and in the
numerous and ingenious theories and suggestions ; but
the necessity of finishing the book soon, and of keeping
it within reasonable size, appear to be responsible for the
less satisfactory accounts of the morbid anatomy and of
the etiology of the lesions in certain of the sections. This,
however, will probably be remedied in later editions.

OUR BOOK SHELF.

The Mechanism of Weaving. By T. \V. Ko.\. Pp. 464.
(London: Macmillan and Co., 1894.)

One result of the application of the "beer money" to
education is the increasing production of technical hand-
books similar to that before us. Technical Instruction
Committees found, very soon after their responsibilities
were thrust upon them, that there were few competent
teachers of technology, and that the literature of arts and
crafts was very limned. .Many books have been made
for the purpose of supplying the need, some good and
others of doubtful utility. The new conditions have been
favourable to the development of technological books and
teachers, and we must not complain if a few monstrosities
occur in the case of each, for they are more than counter-
balanced by many admirable examples on the other side.
The book under review is one of these new guides to in-
dustries, and nothing but good can be said of it. It deals
with a branch of weaving that has been almost ignored by
previous writers. Much has been written on designing
and fabric structure, but practically nothing on the
mechanical processes of the weaving trade, though new
machinery and new processes have been increasing ever
since the power-loom supplanted the hand-loom. This
gap is admirably filled by Mr. Fox's treatise. The
leading types of weaving machinery are clearly described,
and the numerous illustrations (256 in all) of machines,
appliances, and constructions pertaining to the te.xtile
industry are most instructive. We have no hesitation in
saying that Mr. Fox, who is the lecturer on textile fabrics
at the e.xcellent Municipal School at Manchester, has
produced a practical handbook of great value.

Memorials of Old Whithy. By Rev. J. C. Atkinson,
D.C.L. Pp.326. (London: Macmillan and Co., 1894.)
Fiction, " like the baseless fabric of a vision, leaves
not a wrack behind," because it has no foundation in
iact. Stories that are commonly classified as ''fabulous"
usually have, however, a nucleus of scientific import.
In the words of Canon Atkinson : " The myth, the fable
(of the mystic sort), the legend, has always a base, a
substratum or foundation of some sort. Like the
Pentacle, with its mystic application and use, or the
Svastika, Fylfot, or Hammer of Thor, the Monolith or
Standing-stone — from Jacob's stone at Bethel, and before
and since — it has always had its own something to rest
upon, to spring from its actual material 'base' or occasion."
Scientific inquiry is required to reveal this base ; but by
this we do not mean that facts of physical or of natural
science are necessarily involved in every marvellous
story, but rather that the investigator of legendary lore
should conduct his research in a scientific spirit, discard-
ing speculative evidence, and reducing the problem to
its simplest appearance. This is the spirit in which
Canon Atkinson has investigated the myths, legends,
and traditions connected with Whitby. His treatment
of the Caedmon legend is worthy of special mention. It
will be remembered that Caedmon produced his great
sacred poem at Whitby. According to Baeda, he was a
common cowherd or oxherd, to whom the gift of poesy
was miraculously, or at least suddenly,- given, and this
story has been generally accepted in spite of its great

NO. I 3 I I , VOL. 5 I 1

improbability. Canon Atkinson rids the story of its
miraculous element, and justifies the dictum poeta
nascitur, non ft. He shows that it is largely mythical,
and that Caedmon was probably a homeh native poet
of some genius, but undeveloped, before the Abbess Hild
took him up. This view is practically clinched by
the evidence that Caedmon's name is of Celtic origin,
and that therefore he doubtless possessed the fervid im-
agination and vivid fancy of the Celtic temperament.
It need hardly be said that the miracle described by
Baeda would have been eliminated from the story at
once by a man of science. To us it seems that Canon
Atkinson comes to the only conclusion possible after a
careful consideration of historical records, and a com-
mon-sense view of the case. Other stories and customs
connected with Whitby are discussed with a similar
broad-mindedness, and in a manner which local historians
generally would do well to follow.

Die Schopfung der Tierwelt. Von Dr. Wilhelm Haacke.
Pp. 552. (Leipzig and Vienna : Bibliographisches
Institut, 1893.)

It is just as well to state at once that this is a scientific-
ally-arranged description of the animal kingdom, pro-
fusely and beautifully illustrated with twenty coloured
plates and 469 figures in the text. The illustrations are
certainly among the finest of their class, and one cannot
help regretting that, as the text is in German, the work
can only have a limited sale in England. We can con-
sole ourselves, however, with Mr. Lydekker's ''Royal
Natural Histor\-." now being published, and which is
rather more popular than the volume under review. The
order in which Dr. Haacke treats his subject is un-
common. The book is' divided into two parts,, one deal-
ing with the various forms of animal life from the point
of view of their development, while in the second part
the characteristics of different groups of animals are
described. The first part is thus chiefly concerned with
embryology and palosontology in their relations to
zoological affinities ; with the functions of organs and the
influence of environment ; and with the distribution of
animal life upon the earth. In the second part, inverte-
brated and vertebrated animals occupy two separate
sections, and life is traced from the protozoa up to the
higher forms. From this brief sketch it will be seen that
the book has the theory of evolution as the basis of its
construction. It is therefore a work in which the facts
of natural science are presented in scientific order, and
as such deserves high commendation.

The Vaccination Question. By Arthur Wollaston Hutton,
M.A. Pp. 128. (London: Methuen and Co., 1894.)

Mr. Hutton is among the mistaken people who dis-
trust vaccination, and advocate the repeal of the com-
pulsory laws relating to it. His book is in the form of a
letter addressed to Mr. Asquith, in the hope of converting
him to the opinion that compulsory vaccination is inde-
defensible. It would be futile for us to discuss the subject,
or to attempt to show the fallacy of much of the evidence
adduced against vaccination. We may, however, point
out that, to be consistent, the anti-vaccinationists must
oppose the treatment of diphtheria by anti-toxic serumt ;
but this they are doubtless ready to do.

Dr. William Smellie and his Contemporaries. By John
Glaister, M.D. Pp.360. (Glasgow : James Maclehose
and Sons, 1894.)
Dr. Gi.aister'S book throws some new light upon the
history of obstetrics in Great Britain and France, during
the eighteenth century, in addition to tracing the career
of one of the founders of scientific midwifery.

Smellie's work, however, was so purely medical in
character, that a review of it would be of little interest to
most of the readers of NATURE.

mo

NATURE

[December 13, 1894

LETTERS TO THE EDITOR.

t The Editor does nol hold himself resf>onsiHe for opinions ex-
pressed ty his correspondents. Neither can he undertake
to return, or to correspond viith the writers of. rejected
manuscripts intended for this or any other part of NATURE.
No notice is taien of anonymous communications.]

Dr. Watt's Dictionary of the Economic Products of
India.

The notice of this important undertaking in a recent number
of N.^TfRE (N'ovember l, p. 4), seems to me somewliat un-
sympathetic, and scarcely to do justice to its undoubted merits.
.■Vt any rate, the Government of India, at whose instance the
Dictionary was prepared, might draw the conclusion from the
review that the work was more open to criticism than I believe
to be really the case. A British Government is never too ready
to undertake an enterprise of this kind, and anything of the
nature of a disappointment, when it has made the experiment,
i> little likely to induce it to make another.

.\s I warmly encouraged the inception, and have taken a keen
interest in the progress of the Dictionary, I feel bound to ex-
press my opinion that it is one of the most important aids which
h.i« yet been given to the material advancement of India.

.\s the reviewer correctly remarks, " the large proportion of
the products " of that country " are of vegetable origin." It is,
hoaever, astonishing how little they are known in Europe.
I can speak with some confidence on this subject, because, in
1880, the India Office transferred to Kew the entire economico-
botanical collections forming part of the India Museum at
S>uth Kensington. Their incorporation with the existing con-
tents of the Kew Museum was carried out under my supervision.
1 was struck, as every one has been who has had to do with the
subject, with the profusion of products for which some useful
purpose ought to be found in the arts. As Kew undertook the
duty of acting as referee with regard to these matters,
it became necessary to accumulate information with re-
gard to them. I therefore formed in my office a sort
of rough dictionary, in which I posted up every paper,
document, and scrap of information which I could collect
about Indian vegetable products. This enabled me to deal
rapidly with a great number of commercial inquiries. But for
this purpose. Dr. Watt's Dictionary is an infinitely superior
instrument. It is in constant use in my ofVici, and I am at a
loss 10 conceive how the day's work could now be got through
without it. As I am continually testing its contents, I can only j
express my surprise at the degree of accuracy which Dr. Watt
has attained. I am quite satisfied that the catalogue of not
very important blemishes which the reviewer has managed to
delect, must have co>t him no small labour. The criticisms,
with one exception, I do not propose to discuss. I cannot help,
however, regretting that the reviewer both begins and ends his
article with something like a sneer — in the one case at the size
of the book, in the other at the paper on which it is printed.

Such an encyclopa;dia of economic products as the Dictionary
affords, has long been needed. Indirectly I regard it as one of
the outcomes of the Famine Commission, the second part of
whose Report was presented to Parliament in 1880. In this
Report (p. 175) the Commission point out that "at the root of
much of the poverty of the people of India . . . lies the unfor-
tunate circumstance that agriculture forms almost the sole
occupation of the mass of the population." " Facilities for
obtaining profitable markets (or all sorts of produce " is a neces-
sary means of remedying this slate of things. But it is obvious
that the markets will not come into existence till the products
ate brought into demand by better knowledge.

The bulk of the book and the length of the articles was, 1
imagine, the result of a deliberate plan on the part of the De-
partment of Revenue and .\griculture under whose authority |
the Dictionary was issued. One object in view was to afford to
Indian officials, who cannot be expected to lake a miscellaneous
library about with Ihem, a standard book of reference. The
want of something of ibc kind led Mr. Edwin T. Atkinson, of
the Bengal Civil .Service, to commence a sort of industrial
survey of the north-western provinces. The work is only a
fragment, as Dr Wall's Dictionary has since covered the ground.
The preface to the first part (.\Ilahabad, 1876) puts the needs of
Indian officials so clearly, that it will be useful to quote
from it :

" There ii no subject perhaps regarding which so much

NO. I3II, VOL. 51]

has been written and spoken as ' the development of the
resources of the country.' The phrase is a pretentious
one, and has a rounded, rolling sound worthy of many
of the ideas launched in its name, but really expresses what
must form one of the first duties cA every civilised Government.
As early as June 1S04 a Mr. Got! was deputed to examine the
forests of Rohilkhand and Gorakhpur, with the view of ascer-
taining what local products could be advantageously brought to
the notice of the European world. . . . He was followed by
Laidlay and others, who examined into many of the questions
which even now aie made the subjects of inquiry. Their re-
ports lie unused and unknown amid the twelve hundred volumes
of records composing a portion of the immense library of our
Board of Revenue, and surely it would be a saving
of money and labour if these reports were given to
the official and non-official public. My own inquiries have
shown uie that it is the tendency of all these questions to
crop up in cycles, with the same result, the same perfunctory
procedure ; and were official memory long enough to recollect
what has already been done, and know where to find it, one
half of the erratic circulars which now puzzle and worry the
district officers, might be answered by a reference to the cor-
respondence on the same subject. . . . .\ review of the efTorts
m.ide in the past to attain a knowledge of the resources of the
country is not unmixed with regret. They have all gone by
without leaving any trace behind them, and without advancing
our knowledge one single step, because they wanted organisa^
tion."

In criticising Dr. Watt's Dictionary, a statement like this
should be borne in mind. Dr. Wall has, in fact, and it is one
of the great obligations we owe to him, gutted an.I boiled down
the colossal and in.iccessible official literauireof India. For the
first time, an Indian official has at hand all that is practically
to be said about any local product with which he has to deal.

These points were, I think, not clearly brought out in the
review in N.vture, and I think it is only due to the Govern-
ment of India thai they should be stated.

There is one detailed criticism on which I absolutely take
issue with the reviewer. He devotes some space to the ex-
pression of the opinion that with regard to " drugs and ihera-
peulics, the details are out of place in a description of economic
products." He particularly objects to the inclusion of plants,
"solely because of some medicinal, or supposed medicinal,
use, frequently by ignorant people." To me the subject seems,
on the contrary, of the deepest importance. It is the empirical
knowledge acquired by "ignorant people ' which is at the
base of almost all our knowledge of drugs. And the extension
of modern therapeutics must in the main depend on following
up the beginnings in new directions which ignorant people have
made. In this respect the Dictionary is a mine of information
available for the guidance of future research. In India itself a
truslworlhy account of the properties of the plants used by the
natives for therapeutic or even criminal purposes, must, it seems
to me, be of everyday utility.

W. T. Thiselton-Dyer.

Royal Gardens, Kew, December S.

I.N your recent review of the above work, attention is drawn
to the startling stalement that " Diamond dust is known 10 be a
powerful mechanical poison." This statement, occurring as it does
in an official work, issued by the Government of India, aroused
my am.azement when I first had occasion to consult the Dic-
tionary. It occurred to me then, and I still think, that the author
would have done better to have quoted the words of Colonel
Wilks on the subject (" South of India," vol. ii. p. 197), namely,
" Whatever doubts may be enleilained of llie fact, there is none
regarding the belief (by the Mahommedans of Southern India
in the power of diamonds .as a poison], and the supposed
ponder of diamonds is kept as a last resource like the sword of
the Roman, l.ul I never met with any person, who from his
o*n knowledge couM describe its visible 1 fleets, &c."

Better still perhaps, iiislcad of giving what, as you have pointed
out, is an erroneous account of the celebrated Gaikwar's case,
Dr. Watt might have quoted the emphatic words of the Com-
missioners who tried the Gaikwar, that " Diamond dust accord-
ing to the best aulhoiities has no injurious eflecl on the human
body " (" Commission Report," p 223)'

With some inconsistency — although Dr. Watt quotes an
account of the reputed medicinal qualities of prepared diamond

December [3, 1894J

NA TURE

151

— he does not follow up the first statement by including
it in his list of reputed poisons (vol. vi. p. 309.)
It may be added that Dr. Watt's selection of authorities,
generally, appears to be somewhat capricious. He does not
appear to be acquainted with Garcia de Orla's famous work on
Indian drugs, for he gives Linschoten and others credit for
observations not originally made by them, but by Garcia, e.g.
art. Miinna.

Again, when writing of ambergris, surely he might have found
some more direct source of information regarding a product
derived from whales, than a work, excellent though it be,
which deals properly with the products of the Punjab.

I write as one not wishing to find fault, especially as I recog-
nise the good services done by Dr. Watt, but because I believe
such a work so brought out, should be a faithful .■nummary of
recorded facts, which, if hitherto only known to comparatively
few, should be so stated as not to mislead the many who may
have occasion to refer to the Dictionary. V. Ball.

Science and Art .Museum, Dublin, November 19.

Drift-Bottles in the Irish Sea.

In Nature for Nov. 8 (p. 35) mention is made of the travels
of some drift-bottles in the south seas. It maybe of interest
to put on record the results so far obtained of the distribution
of bottles set free by the Liverpool Marine Biology Committee
in order to get further information in regard to those currents
in the Irish Sea which would affect small floating bodies. The
objects we have had in view are : (l) A purely scientific matter,
the source and distribution of the plankton ; and (2) the probably
utilitarian object of determining the movements of the food
of fishes, and so one of the causes of their migrations, and also
the drift of the floating ova and embryos of food fishes. The
tidal currents of the area in question are to a considerable ex-
tent known, and marked on the charts and given in books on
" Sailing Directions"; but to these currents have to be added
the modifying influence of prevalent winds, and what we want
to get at is the resulting average effect. We want to know in
what direction an object set floating at any spot will probably
be carried at various times of the year in ordinary weather. The
surface organisms are such feeble swimmers, if locomotory at
all, that any results obtained from small floating bottles may
reasonably enough be regarded as holding good for the plankton.

The form of bottle we have chosen is cheap, buoyant, strong,
and well corked. It measures 7 5 cm. in length over all, and
I -8 cm. in diameter. Inside it is placed a printed paper re-
questing the finder to fill in date and locality, in spaces left for
the purpose, and post it back to myself. The papers are
numbered, and are folded in the bottle in such a way that the
distinguishing numbers can be read through the glass, so as to
ensure that the bottles are set free in consecutive order. After
the bottle has been corked up, the end is immersed a couple of
times in melted paraffin, so as to close up the pores in the cork.
None of the papers that have been returned show signs of
water having got into the bottles.

As to the distribution, I sent off the first few dozen myself
from steamers crossing between Liverpool and the Isle of Man,
dropping a bottle over every fifteen or twenty minutes between
the Bar and Douglas, and also from a steam-trawler while
dredging between Port Erin and Ireland. Mr. A. Holt has
had a number of bottles distributed for me from his outward-
bound steamers on their course between Liverpool and St.
George's Channel, and from the Mull of Galloway round to
theMcisey, The Lancashire Sea-Fisheries steamer has set free
another series along various lines up and down the Lancashire
coast, and finally some have been set free at equal intervals of
time during the rise and fall of the tide from the Morecambe
Bay Light vessel in the northern part of the district, and from
the Liverpool Northwest Light vessel in the southern pan.
The distribution has now been going on since the beginning of
October, and a very fair proportion (about one out of every
three) of the papers have already been returned to me duly
filled in and signed. They have come from various parts of the
coast of the Irish Sea — Scotland, England, Wales, Isle of Man,
and Ireland. Some of the bottles have gone quite a short
distance, having evidently been taken straight ashore by the
rising tide. Others have been carried an unexpected length —
f i'. one (No. 35) set free near the Crosby Light vessel olT
Liverpool at 12.30 p.m. on October I, was picked up at Salt-
coals in Ayrshire on November 7, having travelled a distance

NO. 13 II, VOL. 51]

of at least iSo miles (probably far more) in 37 days or less ; an-
other (H 20), set free near the Skerries, Anglesey, on October
6, was picked up at Ardrossan, Ayrshire, on November 7,
having gone at least 150 miles in 31 days.

It would be premature as yet, until many more dozens or
hundreds have been distributed and returned, to draw any very
definite conclusions. It is only by the evidence of large
numbers that the vitiating effect of exceptional circumstances,
such as an unusual gale, can be eliminated. However, I may
state, as provisional results so far, that nearly fifty per cent, of
the bottles found have been carried across to Ireland, and they
are chiefly ones that had been set free in the southern part of the
district (between Liverpool and Holyhead) and ofi" the Isle of
Man. The bottles set free along the Lancashire coast and in
Morecambe Bay seem chiefly to have been carried to the south
and west — to about Point of Ayre, in North Wales, and Douglas,
in Isle of Man. It is apparently only a few that have been
carried out of the district through the North Channel. The
most interesting point, so far, is that so many of the bottles have
been stranded on the Irish coast, although they were sent off
for the most part much nearer to the English and Welsh coasts,
showing no doubt the influence of the spell of easterly winds
in October. W. A. Herdmam.

University College, Liverpool, November 29.

The Explosion of Gases in Glass Vessels.

When Prof. Lothar Meyer was visiting Manchester a few
years ago (on the occasion of the meeting of the British Associa-
tion), he surprised me by saying that it was his custom in lecture
to explode mixtures of ethylene and other hydrocarbons with
oxygen in glass cylinders, some 10 to 12 inches long by li to
2 inches in diameter (if I remember rightly), and that he had
never had an accident. I suppose I did not sufficiently conceal
my surprise, for he immediately demanded that we should go
to the laboratory and repeat the experiment. Not having a
mixture of ethylene and oxygen ready, I could not accept the
challenge on the spot. The issue was therefore changed.
Prof. Lothar Meyer said that lie would fire a mixture of hydro-
gen and oxygen in a thin glass test-tube without breaking it. I
confess I was sceptical, until I saw him do it time after time
without injury. He argued that if the thin test-tube would
withstand the explosion of hydrogen and oxygen, a thick glass
cylinder would withstand the more violent explosion of a hydro-
carbon. Nevertheless I ventured to warn him against trying
the experiment with either acetylene or with cjanogen, the two
gases I had found to explode more violently than any others,
specially wilh a small quantity of oxygen. Prof. Meyer's
recent accident with acetylene and oxygen has led him to warn
chemists against the danger of that mixture. I would wish to add
to that warning that the danger is equally great, if not greater,
with a mixture of cyanogen and oxygen.

Prof. Lothar Meyer asks how we can account for the violence
of the explosion of acetylene, when the velocity of its explosion
is so little greater than the velocity of explosion of marsh gas
and of ethylene, while it is far less than that of hydrogen? It
is important to bear in mind that the explosion-wave is not set
up at once ; when a gaseous mixture is ignited at the open end
of a tube the flame starts comparatively slowly. The violence
of an explosion in a short tube depends mainly on whether the
explosion wave is set up or not. I think the immunity
so long enjoyed by Prof. Meyer's cylinders depends on the
fact that the wave was not set up. I have found that pieces
of strorg combustion tubing, which will stand an hydraulic
pressure of twenty-five atmospheres, are broken by the ex-
plosion-wave of hydrogen and OX) gen. It requires exception-
ally strong glass tubes, capable of bearing at least 120 atmo-
spheres, to withstand the shock of the explosion-wave with
cyanogen or acetylene. With both these gases it is the incom-
plete combustion which occurs with the greatest rapidity and
violence. According to the hypothesis I have published, viz.
that the explosion-wave travels with the velocity of sound in
the burning gases, the pressures existing in the explosion-wave
of cyanogen and acetylene with their own volume of oxygen
are 1 17 and 105 atmospheres respectively. <^uite apart Irom
this hypothesis, the pressures may be calculated from Riemann's
equation for the propagation of a wave of constant type, since
we know the density of the unburnt gases and the rate of pro-
pagation of the wave. According to Riemann's equation the
pressure in the cyanogen explosion is 140 atmospheres, and in

1^2

NATURE

[December 13, 1894

the acetylene explosion 114. Some experiments I have recently
made in conjunction with Mr. J. C. Cain confirm these calcu-
lated pressures. When the explosion-wave was propagated
through a mixture of equal volumes of cyanogen and oxygen it
broke soda-lime tubing of iS m.m. external diameter andv2"5
m.m. thickness. Pieces of this tubing broke at a mean
hydraulic pressure of 70 atmospheres. Green glass tubing of
2"S mm. thickness withstood the explosion ; it broke at a
pressure of 140 atmospheres. More exact results were obtained
when the gases were diluted with an equal volume of nitrogen :
—C.N. -r O5 -f 2N3 = 2CO + 3N5.

Pieces of the tube which were broken by the explosion were
broken hydraulically at 63 atmospheres ; pieces of the tube
which withstood the explosion were broken hydraulically at S4
atmospheres.

Prtisura in the Explosion IVave.

Gaseous mixture.

Calculated pressures.
kieni.tnn. Dixon.

Observed
pressures.

C,Xj -^ o.

140 At. 117 M. 70- 140

-I-

C.N-, -I- Oj H- 2N. 73S At. I 57 At. 63-84

When oxygen is added to these mixtures the rate of explosion
is diminished and the pressure falls. For instance, according
to Kiemann's equation, the pressures produced in the explosion
of acetylene with increasing quantities of oxygen are as
follow : —

' ia^eous mixture.

C,H, + 0,

Calculated pressure,
114 At.

C.Hj + O3

98 At.

CjH, -J- r>.

78 At.

In the same way the pressures produced in the explosion of
ethylene with different quantities of oxygen may be calcu-
lated :—

The lowest of these pressures is probably sufficient to break
the cylinders used by Prof. Lothar Meyer. As Prof. Thorpe
says in Nature, the danger of acetylene lies in the rapidity
with which the explosion-wave is initiated, even when the air
alone is used as " tamping." Safety lies not in thickening the
glass, but in shortening the tubes. H. B. Dl.\ON.

Owens College, December i.

The Kinetic Theory of Gases.

I HAVE to thank Mr. Culverwell for bis reply to my letter
on the discussion at Oxford. To quote his own words (in
answering Mr. liurbury, p. 105J, Mr. Culvcrwell's letter was
" exactly the kind of letter that I hoped to elicit," as I had
not been able to recall the exact purport of Prof. Fitzgerald's
"onslaught." Although Prof, liultzmann made no attempt to
answer Prof. Fitzgerald's objections in the short space of time

NO. 131 I, VOL. 51]

available after the other speakers had concluded, he several
times mentioned the question to me after the debate as one
which had not been hitherto satisfactorily cleared up. In pre-
paring my Report, the question of the spectra of gases came
prominently before me, but I purposely refrained from express-
ing my own opinions on a subject about which so little had been
written in a report which was intended to be chiefly a record ol
work actually done. My frequent allusions to the question of
the uniqueness of the Bollzmann-Maxwell Law were intended,
however, to pave the way, if possible, for an explanation of the
discrepancies alluded to by Prof. Fitzgerald, and I should like
now to attempt to answer some of his objections.

According to Mr. Culverwell, Prof. Fitzgerald asked why the
ether, the solar system, and the whole universe were not sub-
ject to the Boltzmann-Ma.xwell Law ? Let us take the solar
system first.

The law is obviously inapplicable to a single system (as I
pointed out in my Report, and hope to prove still more con-
clusively shortly). In order to apply it, Prof. Fitzgerald
would have to take an infinitely iar^e number oj sular
systems, each consisting of similarly constituted planets differ-
ing, however, in their motions. What the law states is
that, if the coordinates and momenta of the different systems
were at any instant distributed according to the Boltzmann-
Maxwell distribution {i.e. with frequencies proportional to e - ''•),
they would be so distributed at any subsequent instant In the
absence of mutual action between the various solar systems, this
would not be the only permanent distribution, nor would there
be any tendency to assutne such a distribution. If, however,
the different solar systems were to collide with or encounter one
another at random in such a way that transference of energy
was liable to take place between any of the coordinates ol any
one system and any of the coordinates of any other system, the
Boltzmann-Maxwell distribution tiw/A.' probably be unique,and
there would be a tendency to assume such a distribution as
the ultimate result of .i great number of encounters taking place.
Will not Prof. Fitzgerald agree to this?

With regard to the ether, I notice that Mr. Culverwell
emphasises Prof. Fitzgerald's contention that the investigations
ought to lake " ethereal " as well as " molecular " coordinates
and momenta into account. But here I agree with Prof. Boltz-
mann that the onus probandi lies with physicists. If they will
give us a clear and definite statement as to what arc the co-
ordinates and momenta of the ether., and how transference oj
energy lakes place hel-vc<n these and the molecules, and if they
will show that the Boltzmann-Maxwell Law is violated under
conditions under which we have proved it to be unique, a " true
bill will have been found."

.\t present all we assert is that if the " ethereal coordinates
and momenta " satisfy a determinantal relation similar to that
proved on p. 22 of Dr. Watson's new edition, the Boltzmann-
Maxwell distribution, // // ever once existed, will be permanent
in the absence of disturbing influents. But the test case in
which molecules are regarded as smooth solids symmetrical about
an axis (see my Report, § 45, case iii.) affords an instance in
which partition of energy does not t.ike place between all the
coordinates of a system, the angular velocity of each molecule
about its axis of symmetry being constant and unaffected by
collisions, and therefore independent of the Bollzm.inn-
Maxwell Law. .\nd why should not a similar explanation
be applicable to the ether ? -At any rate, this hypothesis is sup-
ported by the views advanced by I'rof. Oliver Lodge at the Not-
tingham meeting of the British Association (" Nottingham
Report," p. 688). G. M. Bryan.

Cambridge, November 30.

It appears to me that the difficulty raised by recent critics
against Maxwell's law of partition of energy in the theory of
ga^cs, and Bollzmann's minimum theorem relating thereto, by
consideration of the effect of a complete reversal of the motions,
is capable of direct explanation ; and that whatever weak points
the theory may have, they are not in that direction. Indeed, if
that were not so, the criticism would apply equally against the
Second Law of Thermodynamics.

The theorem in question is that there exists a positive function
belonging to a group of molecules, which as they settle them-
selves into a steady slate maintains— on the average derived
from a great number of configurations — a steady downward
trend ; ihat the .Maxwcll-Boltzmann steady slate is that one for

I

December 13, 1894I

NA TURE

■OJ

which this function has finally attained its minimum, and is thus
the unique steady state : it still being borne in mind that this is
only a proposition of averages derived from a great variety of in-
stances in which nothing is conserved in encounters except the
energy, and that exceptional cases may exist, comparatively very
few in number, in which the trend is, at any rate temporarily,
the other way. .

Such an exceptional case is in fact the very striking one,
pointed out by Maxwell and Helmholtz, in which the motions
of the system are all at some stage precisely reversed, so that it
retraces its previous history backwards, and the trend of the
reversed system is therefore in the opposite direction to the one
which would lead towards the steady state. Now it has been
assumed, at first sight plausibly, that there are just as many
cases of this reversed motion as there are of the direct motion ;
and if that were so, it would undoubtedly go hard with the distri-
bution theorem. But a fallacy underlies such an assumption, as
indeed the other accepted proofs of simple cases of the distribu-
tion theorem would lead us to expect. Consider an arbitrary distri-
bution of velocity and configuration of the system to begin with ;
and let it settle down for a time towards the final state, whatever
that may be. Suppose at the end of that time that its velocities
are all reversed ; the system will retrace its course up to the
initial state, but when it has got there, it will presumably go on
settling down towards the final state by another route, because
there is no longer any reason for exceptional behaviour. Thus
there will be only a temporary aberration in the course of the
reversed system ; and further, if the original progress towards a
steady state was at all rapid, this aberration will be sensible only
for a brief time, the remainder of the history of the reversed
motion corresponding nearly to the steady stale. It is true that
if the whole universe were thus reversed, the aberration would
be permanent ; but then the whole universe i> a permanently
dissipative system, and there is no question of a steady state
being attained by it in measurable time. For a finite system,
like a mass of gas imagined as bounded by a rigid envelope,
the case would be different.

Tims even if these reversed states amounted to half the
possible states, there would still be a preponderating, though
not immense, probability in favour of a final settling down. Bat
are these reversed states half the total number ? The character-
istic of such a state is that it is derived from an entirely for-
tuitous initial distribution by a process of change which is in
the direction of the final steady state, whatever that may be,
and much in that direction if the time concerned be consider-
able. It seems then that the number of configurations which
can retrace their history for a sensible time is very much more
limited than the total number of possible configurations, and
that they are simply the exceptions which do not disprove the
rule. For a theorem of average, derived from a very great
number] of instances, is of course not invalidated by picking
out a comparatively small number of instances which depart
widely from the average. J. L.\RM'jR.

Cambridge, December 4.

" Peculiarities of Psychical Research.

Mr. II. G. Wells disposes very aptly of most of the claims
set up by Mr. Podmore and his colleagues to be real scientific
investigators. But, I think, he rather disguises the significance
of the card-drawing experiments to which he refers. The
experiments of M. Kichet and those of the .S. P. R. belong to
two very different categories. In the former case, 7S9 correct
guesses were made in 2927 trials, or a deviation from the most
probable result of 57 or 58 ; this is about 24 times the
standard deviation, or the odds against a deviation in excess of
this amount are only about 100 to I, or odds of only about 50
to I of a deviation of this magnitude either way.

On the other hand, in the S.P. R. trials we have a deviation
from the most probable of 347, about six times the standard devia-
tion. That is to say, the odds against such a result are in round
numbers about 2,000,000,000 to 3 \ Now, this is of a totally
different order to that given by M. Richet's numbeis. I have ob-
tained odds as great as 100 to I against the results of very care-
fully conducted lottery experiments. There is in reality nothing
significant about such odds. But the odds against the S. P.R.
experiments are almost equal to the odds against the Monte
Carlo roulette returns! The experiments are significant, very
significant — not to my mind, however, of telepathy, but of the
want of scientific acumen in the psychical researchers. The

NO. 131 I, VOL 51]

interesting point as to whether an abnormal distribution was
also in the cards turned up as well as in the percipient, does not
appear to have been recorded. Mr. \Yell5has, however, passed
over the difference between the two cases, and given, I fear,
the psychical researchers the chance of a little self-glorification
on their due appreciation of the significant.

University College, December S. Karl Pearson.

Chronometer Trials.

The Mersey Docks and Harbour Board have, by an Order
dated November 29, 1894, modified the regulations under which
they are prepared to issue certificates to those who deposit
chronometers and other scientific apparatus at their Observatory
for test and examination. Under the new regulations, instru-
ment-makers can re-submit their apparatus within a twelvemonth
of first deposit, without any additional fee. In the case of
chronometer-makers this concession will probably be welcomed
for the following reasons. Hitherto, the certificates granted
have simply been regarded as a protection to the public, and
the makers have had 10 apply their own tests to ensure accurate
performance before submitting them to independent examina-
tion. But it will now be possible for makers to spare, in some
degree, their own rigorous control, since the certificate granted
will show the direction in which correction must be made,
and a second certificate will be granted without fee to
the improved instrument. If no alteration be needed, the
time required for the additional trial is of course saved.
Another modification, which will be appreciated by those who
seek certificates for watches, is that affecting the condition under
which these certificates are granted. The alteration will be
best shown by an example. Suppose a watch to have a normal
rate in the first position of trial of nine seconds a day, and
under the various tests to which it is submitted the rate increase
more than a second daily. Such a watch or chronometer, under
the old regulations, would be refused an " A " certificate because
the daily rate increased to more than ten seconds from mean
time. But the watch might evidently be superior to one
with a normal rate of two seconds, and which varied some five
or six seconds in the various stages of its trial. The alteration
in the regulations sanctioned by the Board will n^w permit the
variations to be reckoned from the normal rate, and not from
mean times. William E. Plummer.

Liverpool Observatory, December 10.

Indo-Malayan Spiders.

In* your issue of November 29, Mr. R. I. Pocock,
reviewing Mr. and Mrs. Workman's book on "Malaysian
Spiders," states: "But the pine-apple is a native of South
America, and has only of late years been introduced into
Singapore ; &c." Now, twenty years ago it was as common at
Singapore as any other fruit, more so than many indigenous
ones. How long before it may have been introduced I am
unable to say, but that also should surely be stated "Before
such a conclusion, however, can be looked upon as an estab-
lished fact." I quite grant that in all probabiUly the plant and
spider were introduced simultaneously.

New Club, Grafton Street, W. B. .\. MuiRHEAD.

Death-feigning in Snakes.

In Nature of November 29, p. 107, L. C. Jones asks
whether death-feigning is, among snakes, confined to Hcterodon
plalyrriiinus.

A writer in the American Naturalist, November 1894,
pp. 966-8, tells almost precisely the same story of the
" Moccasin " snake (Ancisirodon) and of " a black or blowing
viper."

He also finds " letisimulation " in the toad, and in certain
arthropods, worms, and protozoa.

December i. Gerard W. Butler.

The alleged Absoluteness of Motions of Rotation.

Proi". Gkelnhill's remarks on my letter on this subject
{Nature, November 29), admitting that he is unconverted, and
throwing out a suggestion that further arguments or explana-
tions are desirable, appear to open a wider question than can

154

NA TURE

[December 13, 1894

be effet lively dealt with in the limits of an ordinary letter. I
propose therefore to deal with the subject in a special article to
be written shortly. A. E. H. LoVE.

St. John's College, Cambridge, December 3.

Gravitation.

May I asit Dr. Joly whether Newton himself did not point
out that a graduated tension excited by matter in a continuous
inextensible medium, of an intensity proportional to the mass
and the inverse distance, would account for gravitation ; and
whether he did not refrain from furiher elaborating this idea
because there seemed at that time no adequate way of explain-
ing the existence of such a tension? Oliver J. Lodge.

" Outlines of Quaternions."

Mav I make a short explanation on one or two points on which
my reviewer (Nature, November 22) does not appear to have
understood me ?

(1) I mentioned Prof. Hardy and Dr. Odsticil's names in one
or two places, because I quoted their language verbally. I found
it was better than any language I could devise.

(2) The extraordinary oversight on p. 76 would never have
seen the light had I had either good health, or the assistance of
a friend, in correcting the proofs of a MS. which was written
at odds and ends of time, at places as widely separated as
Norway, Gibraltar, and India.

(3) My reviewer says eq. S of p. 40 — :' = \' — I — "plays
sad havoc with one's very definitions." Having defined i as a
right versor on p. 37, and explained on p. 39 that «- means ii,
I deduced in the usual manner the eq. — i^ — - I, or —

it = r- = - I = V - I n' - I.
Hence I concluded that « = V - i ; and I fail to see how I
have played havoc with my definitions in doing so. Had I
begun by explaining that Hamilton built up hissystemby treating
\ - I as a right versor perpendicular to the line it operates on,
I might have been open to criticism ; but I did not do so. I
took another course, which may not have been the best one ;
but that is a different thing from violating one's own definitions,

H. W. L. Hime.
24 Haymarket, S.W., November 26.

[A pointed reference to a scientific writer usually implies
one of three things — that the writer is an authority on the
particular subject under discussion, or has made a noted dis-
covery in connection with it, or has been guilty of a serious
blunder. Dr. Odstrcil's corollary hardly comes under the second
category, and Prof. Hardy's statement differs in no essential
word from Hamillon'sown language in the " Lectures " (p. S3).

Equation 8 (p. 40, in "The Outlines of Qualernions ") asserts
the equality of J, y, /■, - i, - /, - /!•, and as these symbols are
by definition all different, the said equation is inconsistent with
the definitions. To speak of v' - I as an indeterminate right
versor, that is, an operator which rotates any vector through a
right angle about an indeterminate axis — a most difTicult
operation for the mind even to imagine — may be permitted as a
figure of speech ; but to equate this backboneless thing to a
real unit vector or right versor with all its powers of action, is
making a serious demand upon the credulity of the student.
After titfinirig i, j\ /• as symbols involving both axis and angle,
what right or reason has Colonel Hime thus arbitrarily to
annihilate the axis ? Is it not playing havoc with the very props
of the calculus? — The Reviewer.]

THE WARBLE FLY}

TT is only within comparatively recent years that much
*■ attention has been paid to the insect pests of the
farm and garden. It is true that when these assume un-
usuilly devastating proportions, especially when they
make their appearance suddenly, as in the case of locust-
swarms, the attention of whole nations is called to them

' " ObMrvationi on Warble Fly or Ox Bot Fly {ffy/'oJtrma I't.'U, Dc
Gmt)." By Eleanor A. Ormirod, F. R.Mct.Soc., &c. (tendon : Simpkin,
Marvhall, Hamilton, Kent, aorl Co , Ltd., 1S94.}

MO. 131 I, VOL. 51]

for the moment ; but the loss caused by less obtrusive
creatures may proceed unchecked and almost unsuspected
for years, without attracting the notice even of those who
suflfer from it most. But there are now many entomolo-
gists, among whom Miss Ormerod deserves special notice
in England, and Prof. Riley in America, who have been
working zealously for years to diminish the loss and
injury caused by injurious insects ; and the pamphlet
before us, with its clear descriptions and statistics, and
excellent illustrations, conveys a mass of information, in
a very handy form, which certainly deserves the most
serious attention of all who are interested in the cattle
and leather trades, whether as graziers, butchers, or
tanners.

The total loss caused by the warble fly in the United
Kingdom alone is estimated at something like /8,ooo,ooo
per annum ; an enormous amount, but which the facts
given in Miss Ormerod's pamphlet fully appear to
bear out. When hides are sometimes so deteri-
orated that the loss on each may be as much as
from twenty-five to thirty shillings, to say nothing
of hides rendered utterly worthless ; cattle killed,
or the best parts of the carcase destroyed, and
diminished yield of milk, the importance of the matter
becomes very apparent. And beyond this, there remains
a very serious question which Miss Ormerod has not
touched upon at all : how far the milk of badly-infested
cows, or the apparently sound portions of a carcase, even
when all the obviously diseased part has been con-
scientiously removed, may be liable to cause disease
in man— disease, possibly, of a nature the origin of which
is at present absolutely unknown and unsuspected by
medical men. And yet we remember once to have met
with the statement that the best hides generally contained
warbles. This, however, if true in any sense, could
only mean that the fly attacks the strongest and healthiest
animals in preference to weaker ones, thereby of course
increasing the mischief produced by its attacks.

Although the insect is so abundant that as many as
500 maggots have been found in .a single hide, yet the
fly is rarely seen. When the cattle are attacked by it, they
gallop wildly about, with their tails in the air, and seek
the shelter of trees or sheds, or rush into the water ; and
in any of these situations, the tly docs not appear to
follow them. Cattle will act in the same manner when
attacked by true gad-tlies, one of the largest British
species of which, Tabaniis boviniis, is likewise noticed
and figured by Miss Ormerod in her pamphlet. The
gad-flies, however, simply pierce the i-kin of the cattle,
and suck their blood, but inflict no permanent injury;
and their larvae are subterranean, and not epizootic.

According to the observations of Prof. Riley in
America, the egg of the warble fly is deposited on,
and not under, the skin. In the earliest stage of
the maggot, which Miss Ormerod has herself ob-
served, it is a small blood red worm-like creature,
scarcely visible to the naked eye, embedded in a
slight swelling, composed of blood-red tissue, through
which a fine channel, no wider than a hair, passes up
to the surface of the skin (Fig. i). In the very young
stage, the maggot, which ahvaysrests with its head at the
bottom of the sore, and the breathing apparatus, which is
at the opposite extremity of the body, directed towards
the opening which communicates with the external air,
is provided with two forks or diggers, probably used for
piercing through the substance of the hitje. Inthisstage,
too, the maggots are capable of inflating theinselves with
fluid which they have apparently no means of discharg-
ing, and become so hard that they can scarcely be
compressed with the fingers, thus forming living and
growing plugs, which act the part of setons, and which
cannot be pressed back out of the wound, more especially
as they arc furnished with short bands of prickles along
a portion of the back. Having penetrated the hide, the

December 13, 1894]

NATURE

'50

maggot rests in the sore, and presently assumes a more
pear-shaped form.

When about one-third grown, agreat change takes place
in the structure of the creature, which, while it was forcing
its passage, was " little more than a bag of fluid, with a
large proportion of the space occupied by brcathing-tiibes."
At this stage, however, " the hard tips necessary, or at
least serviceable for forcing a passage up the hide, are
no longer needed, and they are exchanged for a broad form
of spiracle, and the internal organs become suited to pro-
vide material for the development of the fly, which will
presently form in the dry husk of the maggot, which
serves as the chrysalis-case."

The further development of the maggot is so well
known that we scarcely need trace its course until
it reaches its final shape of a hairy two-winged
fly, not very unlike a small humble-bee in general
appearance, nor need we go into the elaborate accounts
of the enormous loss which is frequently caused by it
to all persons interested in living or dead cattle. The fly

Fig. I- — Hypoderjtta bovls. i, egg: 2, maggot; 3 and 4, chrysalis-case;
3 and 5 natural size, after Bruey Clark ;Jthe other figures, af'ter Brauer, and

appears to be found in most parts of the world, but is
a much greater pest in some countries than in others ;
and it is worthy of notice that, while goats appear to suffer
from the warble as much or more than cattle, horses
seem never to be attacked by it.

Miss Ormerod, however, gives several easy, harmless,
and efficacious methods by which the mischief may be
abated or removed ; and the fly appears to be sluggish,
and not to stray far from where it lived as a maggot, for
after a few years' careful destruction of the maggots, the
pest seems to disappear, without the farm being liable to
fresh incursions from surrounding farms where similar
precautions have not been taken to exterminate the
maggots. Miss Ormerod has evidently done her best
to show the farmers how they may be^t exterminate the
pest ; and if they do not avail themselves of the in-
formation which she has been at so much trouble to
collect and to disseminate, it will not be her fault. The
accompanying illustration is from her useful pamphlet.

W. K. KIKBY.

FERDINAND DE LESS EPS.

n"'HE death of M. de Lesseps, on Friday last, removes
*■ from the world one of its more prominent men.
To say that it was his indefatigable energy which
brought to a successful termination the scheme to pierce
the Isthmus of Suez, is but to repeat what is known to
every schoolboy. With the affairs that during the last
two years have obscured his fame to the political eye we
have nothing to do. The work which earned for him the

NO. 1311, VOL. 5 I ]

title of" Le Grand Franqais " is sufficient to command
the admiration of every man of science. The appre-
ciative obituary notice in the Times, running into
nearly four columns, deals largely with de Lesseps'
diplomatic career, but this does not concern us. We
are indebted to the notice, however, for some of the
following particulars of interest to our readers.

Ferdinand de Lesseps was born at \ersailles, Novem-
ber 19, 1S05. His early public life was spent in the
diplomatic service, for which he manifested the same
predilections as his ancestors. 15ut so far back as 1S41,
the project for cutting through the Isthmus of Suez had
occurred to him. It was not until 1S54, however, that
he first revealed the scheme that will be most lastingly
associated with his name. Two years later. Said Pasha,
the Viceroy of Egypt, granted him a formal letter of
concession. In the same year de Lesseps published a
clear and definite exposition of his views in his pamphlet
" Percement de I'isthme de Suez. Expose et docu-
ments officiels." Many eminent engineers questioned
the practicability of the scheme ; neverthe-
less a capital of two millions of francs was
subscribed, and in 1S59 the works were
commenced.

Difficulties and disputes of a most serious
character cropped up from time to time,
but they were overcome, with the result that
a canal, having sufficient water to admit of
the passage of steamboats, was opened on
August 15, 1865. The channel was widened
and deepened by special machinery, and in
March, 1867, small ships were able to make
use of the Canal. The waters of the Medi-
terranean mingled with those of the Red
Sea in the Bitter Lakes on .August 15, 1S69,
and the event was commemorated by grand
fcles at Suez. On November 20 following,
the Canal was form illy opened at Port Said
amid a series of brilliant festivities. The
Canal is about 100 miles long, with a bottom
width of upwards of 200 feet, and a depth of
28 or 29 feet.

Honours poured in upon M. de Lesseps after the suc-
cessful opening of the Canal. In February, iS/O, the
Geographical Society of Paris awarded him the Em-
press's neiv prize of 10,000 francs. He gave it as a
contribution to the Society's projected expedition to
Equatorial Africa. He was appointed to the rank of
Grand Cross of the Legion of Honour, and received the
cordon of the Italian Order of St. Maurice. The
honorary freedom of the City of London was presented
to him, and Queen \'ictoria created him an honorary
Knight Grand Commander of the iJrder of the Star of
India. In July, 1873, the Paris .Academy of Sciences
elected M. de Lesseps a member, in the place of the late
M. de \'erneuil. In 1875 he published his " Lettres,
Journal, et Documents pour servir a I'Histoire du Canal
de Suez." For this work the French .\cademy awarded
to him the Marcelin Gmirin prize of 5000 francs. In
June, 1 88 1, he was elected President of the French
Geographical Society, in the place of Admiral de la
Roncitre-le-Noury. The Broad Riband of the Persian
Order of the Lion and the Sun was presented to him
in 18S3.

M. de Lesseps promoted the project of the Corinth
Canal, and made a journey in Algeria and Tunis to study
the scheme of Commandant Rondaire for the creation of
an inland sea in Africa — a scheme of which he formed a
favourable opinion. Gradually, however, he became
wholly absorbed in the undertaking which was to prove
his ruin — the Panama Canal. All the world knows how
this ended. .After the humiliating drama had been played
out at the beginning of last year, the central figure sunk

nd 6, fly;
la^inified.

156

NATURE

[December 13, 1S94

into a state of stupor, and in this condition — almost
obli\'ious of everything that went on around him — be re-
mained until he passed into the silence of death.

But let us forget these events. However dark they may
seem to be, they cannot hide from us the wonderful
applications of science we owe to Lesseps.

\Ve learn from the Times that Mdme. de Lesseps has
received many messages of condolence. The Emperor of
Germany telegraphed to her, " All intellectual and scien-
tific people mourn over the tomb of one of the greatest
minds and of a genius which embraced the universe."
Lord Dufferin has conveyed the sincere grief of the
Prince of Wales, as also the sympathy of Lord Kimberley.
It is understood that a committee of the Suez Canal Board
is to propose to the company that a statue be erected
to M. de Lesseps at the expense of the company, and
that the city of Paris is to be asked to grant a site in
one of the public squares.

These expressions show the high regard in which
de Lesseps was held. A still more striking testimony
is afforded by the fact that the Paris Academy of Sciences
adjourned on Monday in sign of mourning, when the
president, M. Loewy, is reported to have said : " Many
storms had latterly broken over the head of the illustrious
veteran. It is, perhaps, not to be too much regretted
that his declining strength had for several years made
him almost a stranger to the melancholy affairs of this
world. His name will for ever be linked with a grand
work, the success of which is due entirely to his glorious
efforts, and will be a memorable date in the history of
civilisation."

Scientific posterity will remember the Academy's act
of respect to de Lesseps, and .^L Loewy's words of tribute
to his colleague's memory.

NOTES.
We are glad to see the report that M. Pasteur, who has been
poorly for some little time, is improving in health.

Prof. G. Lewitzkv, the Director of Charcow Observatory,
has been appointed Director of Dorpa*. Observatory, in succes-
sion to the late Prof. L. Schwirz. Dr. L. Struve goes to fill
Prof. Lewitzky's place at Charcow.

The Academy of Sciences of Berlin has granted a subsidy of
1200 marks to Dr. P. Kuckuck, to aid him in the investigation
of the alga-flora of Heligoland.

Wt learn from the Botaniiches Centralblatt, that Herr W.
Siehe, of Berlin, ha; undertaken a botanical exploration of the
almost unknown region of Cilicia Trachaea.

Considerable changes have recently been made in the
scientific department of Smith College, U.S.A. The botanical
department has been reorganised, and Dr. W. F. Ganong
appointed professor. Miss Grace D. Chester, formerly in-
structor in botany, has been appointed instructor in cryptogamic
botany.

Our correspondent at Cambridge has sent us the following
notes : — The Council of the Senate have appointed Dr. R. D.
Roberts to be a governor of the Royal Holloway College,
Egham. Dr. H. H. Tooth, of St. John's College, has been
appointed an additional examiner in medicine. The Walsing-
ham Medal for biologic.il research has been awarded to H.
Barkill, assistant curator of the Herbarium. The following
awards for Natural Science have been made at Si. John's Col-
lege : G. S. West, Royal College of .Science, London, Founda-
tion Scholarship of /'So a year; E. F. Hudson, Dulwich
College, and T. F. R. McDonnell, St. Paul's School, Minor
Siholarships of Cyi a year ; A. C. Ingram, Felsted School,
Exhibition of Clo.

NO. 131 I, VOL. 51]

A SociETt des Amis des Explorateurs francais has recently
been formed at Paris. Its object is to collect and administer
funds for the purpose of aiding travellers, particularly in their
return, and to contribute to the progress of geography by the
publication of the resultsof explorations, and other contributions
to geographical science. The Society is in connection with the
Paris Geographical Society.

We thought it would come. The anti-vaccinationists, anti-
vivisectionists, and kindred souls have, if only for the sake of
consistency, protested against the new treatment for diphtheria.
At the ordinary fortnightly meeting of the Metropolitan Asylums
Board, on Saturday last, a deputation, headed by Lord Coleridge,
waited upon the Board to present a memorial against experi-
ments being carried out in the hospitals in the Metropolitan
Asylums district in the use of the anti-toxin cure for diph-
theria. The Royal College of Physicians had offered to supply
serum for the treatment of diphtheric patients in the Board's
hospitals, and the General Purposes Committee advised the
acceptance of it, but the deputation wished to stop the action
altogether. By arguments that have been u.-;ed over and
over again, it was urged that the experiments led to in-
jurious effects, and were of doubtful utility. Therefore, the
deputation submitted, "public money ought not to be devoted
to experiments in physiology." The Board, however, thought
differently, for the report of the Committee was adopted.

Prof. W. C. McIntosh writes on the artificial hatching of
marine food-fishes ia Science Progress for December. In the
course of his article, he pleads for increased funds to carry on
experiments on a larger scale than is at present possible at
Dunbar. The sum of £yxK> per annum is granted to the
Scottish Fishery Board for scientific investigations, but really
only /'iSoo a year is available for research. " This income has
to bear the salaries of the staff, experiments in fish-, lobster-, and
mussel culture, the cost of apparatus, the marine laboratory at
St. Andrews, the hatchery for marine fishes, with its small
laboratory at Dunbar, and the carrying out of other scientific
fishery work." Leaving England out of consideration, com-
pare this with what is done on the other side of the Atlantic.
"The United States spends annually ^70,000 on fish-culture
and scientific investigations, and employs two large steamers
and a sailing vessel exclusively for the work. Besides this large
sum, the Fish Commissioners of the various States also disburse
considerably on the development of their fisheries. Canada,
again, expends /■ioo,ooo yearly on her fisheries, of which a
sum of about ;£'io,ooo is devoted to fish culture."

It was pointed out by Lord Rayleigh in these columns in
1883 (vol. 27, p. S3S), that whenever a bird pursues its course
for some time without moving its wings, we must conclude
either (l) that the course is not horizontal, (2) that the wind is
not horizontal, or (3) that the wind is not uniform. Prof. S. P.
Langley's recently published memoir on the internal work of
the wind shows that the condition represented by the third
cause, which Lord Rayleigh believed must sometimes operate,
alw.iys exists. The investigations described in the memoir
distinctly prove that (he wind is never a homogeneous current,
but consists of a continued series of rapid pulsations varying
indefinitely in amplitude and period. These pulsations un-
doubtedly help a bird to maintain lis flight without working its
wings or expending energy. This may be accomplished by a
succession of ascents and descents ; the ascents being made
during the wind-gusts, and the descents during the lulls. Prof.
George K. Curtis, of Washington, has lately investigated
mathematically whether the third case of Lord Raylcigh's
analysis is the one actually employed by a bird in soaring ;
that is to say, he has tested whether the pulsations of the wind,

December 13, 1894J

NA TURE

'57

in addition to being qualitatively applicable, are also quantita-
tively sufficient to produce the result. {Annals of Mathematics,
vol. viii. No. 6.) With this application in view, he has deter-
mined the course in the air of a free heavy plane subjected to
definite wind pulsations. For a period of action of ten seconds,
the following result was obtained " without any internal
source of energy, during the lo seconds of alternate calm and
wind, the plane has in the first 275 seconds made a descent of
36 feet, and in the remaining 7-25 seconds has risen 46-9 feet,
travelling at the same time horizontally a distance of 251 feet,
of which 154 feet is made against the wind. In addition, the
relative velocity of the plane and wind (58"9 feet per second) at
the end of this period is sufficient, if the wind continue with
the same velocity, to yield a considerable further ascent before
the vertical component of pressure is reduced to such an extent
that it no longer exceeds the weight of the plane under the con-
stant angle of inclination." Though the conditions of the
problem solved by Prof. Curtis are seldom met with in nature,
the results he has obtained have a very important bearing upon
mechanical flight.

A NUMBER of papers of considerable value are published in
the MUtheihingen der Prahistorist hen Commission Jer Kais.
Akademic der Wissenschaftcn. (Bd. I, No 3. V.'ien, 1893).
J. Szombathy describes the ceramics discovered by him in a
tumulus at Langenlebarn, in Lower Austria. lie points out that
double and multiple vessels were common in the finds of the
bronze period and first iron age of the eastern Mediterranean
countries, especially in Cyprus and Troas, somewhat rarer at a
later time in the graves of the first Italian iron age, and still
more rare in the later graves of the Ilallstatt period of the
Austrian Alps and of Central Europe. The doubling arose
from the gradual increase in diameter of the lower portion
of the long cylindrical neck of an earlier type of vessel.
Dr. M. Hoernes gives a study of the forms of various pre-
historic objects which he has observed in the museums of
North-east Italy. Amongst other objects he refers to bronze
and iron knives in the museum at Padua. The resemblances in
the handles and ornamentation of certain clay vessels leads
him to the conclusion that the culture of the bronze age
of Northeastern Italy extended to the East, and in-
cluded Bosnia-Herzegovina and Istria ; but from this he
does not deduce an ethnical relationship. In the broni'.e period
of Eastern Upper Italy not only were pile-dwellings inhabited,
but mounds as well, as in Istria and Bosnia-Herzegovina. Even
if related pile-structures are not to be found in the north-west
of the Balkan Peninsula, the difference in the mode of life is
counterbalanced by other considerations. The evolution of the
Italians and the Illyrians later diverged in the historically well-
known way. He would add the Ligurian people as belonging
to the same culture group of that age ; this culture-uni'y
separated these people from other peoples living further north
and south of this zone. Dr. Hoernes also describes some
triangular and other ornaments, human and animal forms,
especially those with associated birds, as well as bronze and
iron fire-dogs. Prof. R. Trampler writes on the oldest graves
in the Briinnen Valley district ; and F. Heger, on finds from pre-
historic and Roman times in Lower Austria. The author of this
well-illustrated paper states that there was a pure bronze age
in the district of Upper and Lower .Vustria, which had points
of relationship with the Western finds, and especially with those
in the North and East.

A CURloi;s formation is illustrated in the first annual report
of the Iowa Geological Survey, published a few months ago.
Good exposures of limestone rocks are found .ill along the
Mississippi from Keokuk to Burlington, in south-eastern Iowa.
The limestone often stands out in overhanging cliffs over the
NO. 1311, VOL. 51]

softer shale beds beneath, and gives the appearance of a cas-
cade, as shown in the accompanying illustration, which is reduced
from a plate in the report. The Survey was only established

in 1892, but the report shows that a large amount of useful
information, of great economic interest to the people of the
State, has already been collected.

The volume referred to in the foregoing note showed us that
the publications of the Iowa Geological Survey were to be of a
high character. The second volume, which reached us a few
days ago, goes to confirm this view. It is a description of the
coal deposits of Iowa, by Dr. C. R. Keyes, and is a model of
what a general report should be. With text running into more
than five hundred quarto pages, eighteen full-page plates of a
high quality, representing interesting formations in connection
with the coal-measures, and over two hundred figures in the
text, the volume is an attractive handbook for the coal-miners
of Iowa. It is not a detailed account of the geological features
of the coal districts — that will follow when sufficient facts have
been accumulated ; it is rather a preliminary report, somewhat
general in character, but sufficient to supply temporarily the
demand for information pertaining to the coal deposits of the
State. Separate volumes will be devoted to practical mining
in Iowa, and to a description of the uses and properties of Iowa
coals. We offer our congratulations to Dr. Keyes and the
geological corps with which he is associated. May their inten-
tions with regard to future work be satisfactorily realised.

In the current number of the Zoologischer Anzeiger (No.
462), Dr. Arnold Graf records some novel observations made by
him in the course of some experiments on the effects of com-
pression on the segmentation of the egg of the sea-urchin
Arbacia. Driesch has already shown that compression of the

»5S

NA TURE

[December 13, 1894

segmenting egg between slide and cover-slip leads to the forma-
tion of a flat plate of blastomeres, and Dr. Graf's observations
coincide completely with those of Driesch up to the 32-ceIl
stage. .\t this point the author determined to remove the
pressure exerted by the cover-slip, and to notice the effect pro-
duced on the egg by this reversion to normal conditions. To
his astonishment he found that, after removing the pressure (by
gradually adding a surplus of water between slide and cover-
slip) the various blastomeres began to fuse together again. In
this way a plate of 15 cells was produced, each cell containing
two and, in a few cases, three nuclei. Shortly afterwards the
separate nuclei in each cell reunited. The last transformation
observed by the author was the conversion of the plate into a
I2cell stage, consisting of eight micromeres and eight micro-
meres. The results of the experiment are full of interest, and
well worthy of renewed trial. The author is certain that
the fusion of the blastomeres took place quite regularly : the
two or three daughter-cells of one mother-cell reunited to form
the single uni-nucleated equivalent of the mother cell again.

Certai.n obscure phenomena connected with the mingling of
two masses of liquid are dealt with by Herr E. Kaiser in the
current n^xahnol Wiedemann' s Annalcn. Two soap-bubbles
or two jets of water when brought into immediate juxtaposition
will not always mingle at once, and sometimes they will not do
sj at all. Impurities in the water or soap solution will
encourage fusion, and so will a difference of potential. Whether
the influence of the latter may be explained on the supposition
of sparks breaking down the intervening layer of air, is a ques-
tion which has been answered in the affirmative. But Herr
Kaiser's experiments tend to show that in reality the difference
of potential simply increases the pressure on the intervening
air, and forces it out at the sides, thus diminishing the distance I
between the two surfaces down to the radius of molecular |
action. He suspended a circular film of Terquem's sugar-soap
solution in a wire ring by a delicate spring balance, and brought
a bubble to bear against it from below. The film and bubble
were placed in electric connection through their supports, and
differences of potential due to I, 2, 3 and more Daniells were
subsequently introduced. With the films investigated, the
time necessary for fusion was about 3 '2 seconds with no differ-
ence of potential, i 4 seconds with one Daniell, and o'4 with
two. With more Daniells fusion took place instantly, and the
films burst in moit cases. The pressure was I "016 gr. The
displacement of air from between the films was studied by the
aid of the Newton's rings formed between them. The rings
widened out, rapidly at first, then more slowly, and the ming-
ling was heralded by the appearance of the grey-blue of the
first order. A difference of potential simply accelerated this
process.

It has been said by someone, that a whole set of meteoro-
logical predictions may be disturbed by a cowboy carelessly
throwing down a burning match upon a prairie. The match
starts a prairie fire which ciuseschanges extending throughoutthe
atmosphere, and so an accident may upset the most carefully pre-
pired forecast. This is, of course, a far-fetched case, but it is
worth while knowing what effects great forest fires have upon
the atmosphere. To this end Prof. Cleveland Abbe, in the
Monthly Weather Revir.u, determines some of the meteorological
results of the extensive forest fires in the United Stales during
July and August of this year. It appears that, with regard to
their influence upon atmospheric moisture, the experience of
the past summer is suffi.-ient to show tliai forest fires are not
necessarily followed by rain, and are not a practical method of
inducing rain in dry scasoni. Comparing the normal maximum
effect of solar heat with the compulation of the effect of burning
fo.est. Prof. .\bbc finds that, in the locality where it occurs, a

NO. 131 I, VOL. 51]

forest fire can heat its atmosphere more than the hottest sun of
June, in the ratio of 10,000 to 750. Fortunately, however, the
general influence of the forest fire upon the whole atmosphere
is much smaller than that of the sun, because the fire is of
small extent, while the sun affects the whole earth. The
actual area covered by the forest fires of August in Minnesota,
Wisconsin, and Michigan did not exceed five thousand square
miles, whereas the area covered by the smoke, and, therefore,
hot air, from thcie fires before the heat was all lost by radiation,
was not less than one million square miles. A comparison of
the solar effect over this large area and the more intense forest
fire effect over the small area, shows that the foimer is fifteen
times that of the latter. Prof. .\bbe"s calculations thus afford
no foundation for the belief that forest fires have important
meteorological sequel*. The story of the connection between
careless cowboys and atmospheric circulation is, therefore, no
longer worth telling.

The current number of V Elettricista contains a description
of a new method for measuring small resistances, due to Dr.
Pasqualini. This method, which requires no special app.aratus
that cannot be easily set up in the laboratory, consists in having
a coil, composed of a few turns of wire, wound double, so that
there are two similar circuits. This double coil is fixed to the
case of an ordinary galvanometer, so as to act on the needle.
The main current sent through the resistance to be measured
passes through one of the circuits of this auxiliary coil. .\ shunt
circuit to the resistance is formed by the second circuit of the coil,
the galvanometer, and a resistance-box. The connections are so
arranged that the main current and the shunt current in the
galvanometer coils tend to turn the needle in opposite direc-
tions. The resistance of the shunt circuit is varied till the
galvanometer deflection is zero. Suppose K is the galvano-
meter constant, while Kj is the constant which expresses the
effect of either of the circuits in the auxiliary coils on the needle,
and if I and / are the total main current and the fraction which
passes through the shunt circuit respectively. Then K i = K, I
- Kj », or if K is the resistance of the shunt circuit, the re-
sistance to be measured = ,— f'^- The value of the constant
Jv

' can be obtained by performing the experiment on a known
K

resistance. With an auxiliary coil consisting of two similar circuits

containing four turns each, and a Wiedemann galvanometer of 8

ohms resistance, the author finds he can measure a resistance of

■0002 ohms within ^ I, using a standard ohm to detennine
1000

the constant ' .
K

In a paper communicated to the Physical Review, Mr. S. II.
lirackelt gives an account of some experiments he has made on
the magnetic properties of iridium. The samples used contained
9S per cent iridium, with some platinum, and a trace of phos-
phorus, but no iron. A bar of the metal 1 3 3 m.m. long,
32 m.m. wide, and 09 m.m. thick, when brought into the field
of an electromagnet, set itself at right angles to the lines of force,
and became permanently magnetised in a transverse direction,
and when suspended, freely set itself E. and W. The perme.
ability of a larger bar was tested, and was found to be unity ;
and although the specimen was sharply struck while in the mag-
netising coil, no induced magnetisation was produced.

A NiiW illustrated descriptive price list of electric ami
magnetic apparatus, for use in colleges and scientific institu-
tions, has been issued by Messrs. Kmg, Mendham, and Co.,
Bristol.

We have received a Jahibuch containing the results of
meteorological obiervations made at the observatory of the

December 13, 1894]

NATURE

159

Magiieburgischen Zeitung during 1893. The volume is edited
by Herr A. W. GiUtzmacher, and is in its thirteenth year.

The Bulletins of the Michigan State Agricultural College
Experiment Station, for October, contain an exhaustive paper
on the insects which attack clover, by Mr. G. C. Davis, and
one on rape as a (orage-plant, by Mr. C. D. Smith and Mr. F.

B. Mumford.

The eighth part of "The Natural History of Plants" has
been published by Messrs. Blackie and Son. It deals with the
genesis of plant-offspring, one section being devoted to asexual
reproduction, while the other refers to reproduction by means
of fruits.

MM. J. B. B\iLLii;RE et Fils, of Paris, following other
firms of booksellers and publisher^, have commenced the issue
of a monthly list of new books, under the title Bibiiographie
des sciences naturdles. The list for November comprises the
titles and prices of important works on protozoa, sponges,
coelenterata, echinoderms, &c.

The Transactions of the Academy of Science of St. Louis,
U.S.A., include a paper on Sclerolinia Libertiana, a fungus
parasite of the sunflower, by Prof. L. H. Pammel to which is
appended a bibliography of the fungus diseases of roots,
covering thirty- seven pages ; also a further instalment of Mr.

C. Robertson's observations on the relationship between flowers
and insects in the process of pollination, the present paper
treating of American species of Rosacc^T and Composites.

A VOLUME containing a number of important papers and
reports relating to the gold fields of New Zealand has just
reached this country. The mining industry has formed a large
factor in the advancement of the colony, and the statement issued
by the Government shows the direction in which further
developments should be made. The volume comprises reports
on the gold fields and cial mines, geological reports on the
older quartz-drifts in Central Otago, and a report on deep
quartz-mining in New Zealand.

Mr. Edward Stanford has acted wisely in reissuing Dr.
A. R. Wallace's standard work on "Australasia" in a revised
and enlarged form. The first volume of the new edition, dealing
with Australia and New Zealand, was published a few months
ago. The second volume, which has just appeared, has for its
subject Malaysia and the Pacific Archipelagoes, being an
enlargement of the part devoted to that region in the original
work. Dr. F. H. H. GuiUemard is responsible for the new
work, and he has performed his task so thoroughly that the
present volume occupies nearly twice the number of pages pre-
viously allotted to the region with which it deals. The work
is certainly the most interesting and accurate account extant on
the tropical portion of the Eastern Archipelago.

Stude.\ts of the anatomy of the horse will be glad to learn
that the second volume of the elaborate "Topographische
Anatomic des Pferdes," byDrs. \V. Fllenberger and H. Baum,
has been published by Paul Parey, Berlin. The first volume,
dealing with the structure of the limbs of the horse, appeared in
the spring of last year. The volume just received has for its
subject the head and shoulders ; while the third, which the pub-
lisher informs us will be issued early next year, will be devoted
to (he trunk. We shall review the work when it is completed.
So far as we can at present judge, it promises to be a useful
contribution to the literature of the subject, possessing both
scientific and practical importance.

Prof. W. Nernst's important treatise on " Theoretical
Chemistry, from the Standpoint of Avogadro's Rule and
Thermodynamics," the German edition of which was enthusi-
astically received last year, has been translated by Prof. C. S.

NO. 131 I, VOL. 51]

Palmer, of the University of Colorado, and the translation will
shortly be published by Messrs. Macmillan and Co. The work
is a development of Prof. Nernst's introduction to the " Hand-
buch der Anorganischen Chemie " of Dr. O. Dammer. It is,
however, quite an independent text-book for students of the
new physical chemistry, and includes the results of all recent
investigations bearing upon that science. The book will serve
at once both as a treatise in itself, and also as an introduction to,
and companion in, the larger field covered by the Zeitschrijt fUr
Physikalische Chemie and the related literature.

Another scientific work which Messrs. Macmillan will
shortly issue, is " Steam and the Marine Steam Engine," by
Mr. John Yeo. The book is chiefly intended for naval
officers, and for students of engineering in the earlier part of
their training. It aims especially at giving a sound general
knowledge of the propelling machinery of ships, and of various
matters connected with its use and management.

In "Darwinism and Race Progress," which Messrs. Swan
Sonnenschein and Co. will shortly publish. Prof. Haycraft
shows how the racial deterioration which would of necessity
ensue upon our modern care of the sickly and enfeebled, may
be counteracted by a keener public conscience. Our preserva-
tion of unworthy types by public and private charily is strongly
animadverted upon, and with regard to intellectual develop-
ment, it is pointed out that the present democratic movement,
while it gives a chance to the clever and capable of becoming
educated and well-to-do, entails upon them conditions which
generally imply late marriages and relative sterility. Without
supplementary action, nothing could be devised which would
more effectually breed capacity out of the race.

Two volumes have lately been added to the comprehensive
engineering division of the Encyclopedie Scientifique des Aide-
Memoire, published jointly by Gauthier-Villars and Masson.
They are " Les Chronometres de Marine," by M. E. Caspari,
and " Torpilles Scches," by M. E. Hennebert. As is the case
with all the volumes in the same series, the two new ones aie
practical handbooks of a very instructive character. In the
former, the construction of chronometers, and the theory relat-
ing to it, are clearly described, and a deal of space is devoted
to the effects of various conditions upon the rate, and also to
the determination of the coefficients of the rate-formula. The
determination of longitude by means of chronometers, and the
methods of testing and comparing the instruments, are con-
cisely described. Both M. Caspari's work, and that by Lieut. -
Colonel Hennebert on torpedot-'s, bring together a lot of scattered
information of great use to students of the subjects with which
they respectively deal.

Commercial geography is just the kind of subject to be
fostered by County Councillors, hence, from the time that
the Technical Instruction Act came into operation, there
has been an increasing demand for text-books upon it.
The first edition of Dr. H. R. Mill's "Elementary Com-
mercial Geography," in the Pitt Press Series (Cambridge
University Press), appeared in iSSS, when the boundary
line of commercial geography was in a more or less
nebulous condition. Thanks to the impetus that has been
given to the subject during the past few years, the book has
reached a second edition. The new issue is not, however,
merely the original work reprinted, for it has almost entirely
been rewritten. To quote the preface : " The book has been
revised throughout by the aid of official publications, and the
facts are as far as possible brought down to date. It is enlarged
by treating more fully of the.principles of commercial geography,
by describing the .\frican possessions of the European powers
in greater detail, and by many small additions in every chapter."

i6o

NATURE

[December 13, 1894

These additions have enlarged the book from 132 to 181
pages, and have correspondingly increased its value. It would
be difficult to find an elementary class-book of commercial
geography constructed on better lines, or in which the informa-
tion is more concisely and accurately stated.

The additions to the Zoological Society's Gardens during the
past week include a Spotted Owl {Athene brama), four Grey
Francolins {Francolinus /•onticerianu!), three Rain Quails
Coturiiix eoromanJelica), an Indian House Sparrow (Passer
dameslicus), two Redheaded Buntings {Emteriza luleola), two
Nutmeg Finches (Miitiia riibro-iiigra), a Spotted Turtle Dove
(Turtur meenti) Uom India, presented by Mr. E. W. Harper,
a West African Love Bird [Agafornis pullaHa) from West
Africa, presented by Mrs. Robinson ; a Reticulated Python
(Python reticulatus) from Malacca, presented by Mr. Sigis-
mund Bruzaud ; an American Black Bear ( Ursus americanus,
var. cinnamonia) from the Rocky Mountains, two Common
Cassowaries (Casuarius galeatiis) from India, a Red-vented
Parrot (Pionus menstniiis), two Orange-flanked Parrakeets
(Brotogerys fyrrhopterus) from South America, a Scops Owl

(Scops ) from Formosa, deposited ; a Short-billed Toucan

{Ramphaitos brevicarinatus) from Central America, received in
exchange.

OUR ASTRONOMICAL COLUMN.

Motion .^nd Magnitude — Students of elementary astro-
nomy nften believe that stellar motions in the line of sight
soon produce changes in the magnitudes of stars. Motion
towards the earth involves, of course, a certain increase
of magnitude, and a motion of recession must carry
with it a decrease, but the amount in the case of a star
is far too small to be measurable, even if the magnitudes
are observed during many generations. At the meeting of
the Amsterdam .\cademy on November 24, Prof Oudcmans
communicated the results of an investigation to determine exactly
how long stars of which the velocity in the line of sight are
known would have to go on moving, in order to produce a change
of 01 magnitude. Fiom his own list of parallaxes in vol. 122
of the Aslr. Nachriihten, and Vogel and Scheiner's list of proper
motions in the line of sight (" Potsdam Observations," vii. i.
p. 153, 154), fourteen stars were selected, four of them receding
from, and the remaining ten approaching, the solar system.
Adopting a solar parallax = 8"'8l 5, and the logarithm of the pro-
portion of the increase of brilliancy for one magnilude = 0400,
he found that the period required is given by the formula

years for stars that are receding from,
parallax x motion

and

5916

years for those that are approaching

parallax motion
to the solar system ; the parallax being expressed in seconds,
and the motion in geographical miles (l geographical mile
= 4'6i English miles). Aldebaran proved to be the only star
of which the brightness could, since Ptolemy's time, have ex-
perienced a loss of 01 magnitude by its radial mo'.ion, provided
that the parallax o '52, found by Otto Struve, is trustworthy.
Elkin found a value - o''i2, and adopting this value, the period
becomes 4\ times longer. For the other stars the result was
5500 years at least for Procyon ; while most of them gave ten-
'bousands of years as the result.

The Recent Transit of Mercury.— Details of several of
'he American observations are puSlished in Astronomical
Journal, No. 330. At most of the stations, some of the
<:ontact9 could not be observed on account of clouds, but, on
the whole, a fair amount of success attended the observers.
Prof Voung observed ihe fir-t and second contacts, and reports
that there was a sort of "hardening " of the sun's limb close to
the expected point of first contact a few seconds before the actual
contact look place ; he has now observed this phenomenon
four times, and states that " it may be due to the planet's
obscurvaiion of the brighie<l p.irt of the chromosphere close to
the disc of the sun, or to some difTrjction effect at the limb of

the planet." A large " black drop " was observed two seconds
before the second contact. Prof. Todd failed to observe the
contacts on account of unfavourable weather, but obtained some
results during the passage across the disc. He says :—
" The planet appeared perfectly circular, sharply defined about
the limb, unattended by any halo or atmospheric ring, and of
the same colour as the unibrx of the spots on the sun. No
attendant satellite of Mercury was seen, nor could any bright
spot be discerned upon the centre of the disc, although intently
looked for. Any satellite smaller than 100 miles would
have escaped detection."

The New Achromatic Object-gl.ass. — Engineering for
November 23 and 30 contains a full account of a fine I2.\ inch
equatorial that has just been built by Messrs. Thomas Cooke
and Sons, York, for the new observatory at Rio de Janeiro,
together with a sketch of the Buckingham Works at
York. The description is accompanied with twenty-nine
detailed drawings of the instrument. It appears that the
works are the only ones in this country where every part
of a modern astronomical telescope is constructed ; with the
exception of the actual making of the glass, everything is
done on the premises, even the heavy
cast-iron pillars being made in the
firm's own foundry. The new instru-
ment, with Messrs. Cooke's standard
form of equatorial mounting for large
refracting telescopes, is fully equipped
for all branches of astronomic.il
research. The clock, too, has all
the latest improvements for adjust-
ment. The object-glass is of the three
lens form, invented by Mr. Taylor,
who deserves the thanks of astro-
nomers for producing an objeciive
which, whilst made of durable kinds
of glass, and of moderate focal length,
is perfectly achromatic. How this
end is attained was described in these
columns on March 15 {\o\. xlix. p.
464). A section of the lens is shown
in Fig. I. The first, Lj, is made of
baryta light flint, having a refractive
index of I "5637 for the I) ray, and
its reciprocal of dispersive jiower is
50'6. The second lens, l ^., is made
of anew glass known as boro silicate
flint. This glass has a refractive
index of l •54685 for the D ray, and
the reciprocal of its dispersive power
is 50*2. The third lens, 1.3, is made
of light silicate crown glass having
the following characteristics : re-
fractive index for D ray, I '5109 ; re-
ciprocal of dispersive power 60*4. By
suitably proportioning the various
radii of the lenses, the middle nega-
tive lens may be made to almost
ex.ictly compensate for the dispersion
effected by the other two, and this
without necessitating any exception-
ally great focal length. If necessary this may be made so
small as fifteen times the aperlurc, and there is no difficulty
whatever in making a glass with a focal length of eighteen
apertures. A small space is provided between the second
and third lens, the object of this being to make the
correction for spherical aberration as complete as possible ;
and when the thickness of this space is properly proportioned,
there is an entire al>sence of spherical aberration for all colours
of the si)ectrum. Object-glasses made on this plan have been
tested by astronomers for visual and photographic observations.
In both cases the stellar images showed no indications of
residual colour, the lenses behaving just like the mirror of a
reflector.

Lphemeris for Swift's CuMet. — The surmise noted in
these columns last week has proved to be correct. M. Schulhof
shows pretty conclusively, in the current Coinptei-renJus, that
Swift's new comet is really identical with I)e Vico's comet
1844 I. The subjoined epliemcris is from one given by Prof.
Lamp in the Astronomischc Naclitichtcn, No. 326O.

Fig. I.— Section of the New
Object-gl.iss.

NO. 13 II, VOL 51]

December 13, 1894J

NATURE

161

Ephemeris for Berlin Midnight.

1894. R.A. (app.) Decl. (app.) Brightness.

h. m. s.

Dec. 13 ... 23 21 36 ... -s 339

,, 15 ••• 26 46 ... 4 557 •• 0'53

„ 17 •• 31 52 ■•• 4 17-9

,, 19 •■• 36 54 ■•• 3 40'S ■■• 0-48

„ 21 ... 41 53 ■ ■ 3 35

,, 23 ... 23 46 48 ... -2 26-9 ... 0-43

The brightness of the comet oa November 21 has been taken
as unity.

A New Star? — The Rev. T. E. Espin has announced that
a very red star of the eighth magnitude, not in the Bonn
DurchmusteruDi;, was found by him on November 29, in R..\.
'7h. 54'3ni. Decl. + 58' 14'. The spectrum belongs to
Secchi's Type IV.

PROF. VICTOR MEYER'S NEW METHOD OF
DETERMINING HIGH MELTING POINTS.

A DESCRIPTION of improved apparatus for the determina-
■^ lion of high melting points, by his admirable new method,
is contributed to the current Bcrichte by Prof. V'ictor Meyer, in
conjunction with hisstudents Messrs. Riddleand Lamb. The sim-
plicity of the method will doubtless cause it to take rank immedi-
ately among the standard processes for the determination of
physical constants, and alongside the universally popular method
of determining vapour densities, which we likewise owe to the dis-
tinguished Heidelberg professor. Naturally, however, operations
at temperatures higher than those at which the hardest varieties
of glass soften, must perforce be conducted in apparatus con-
structed of platinum, just as in the cases of the determinations
of vapour density at the same high temperatures. One of the
main advantages of the method is that it only necessitates the
use of a very small quantity of the substance whose melting
point is to be determined, thus enabling it to be extended to
compounds of the most extreme rarity.

The method is based upon the principle of measuring the
temperature by means of a miniature air thermometer constructed
of platinum, the air contained in which is expelled, at the
moment when the fusion of the substance under investigation
occurs, by means of a soluble gas into a gas-measuring vessel
filled with a liquid capable of dissolving; the expelling gas. The
substance whose melting point is to be determined is placed in
a small and very narrow platinum tube, which is fixed to the
bulb of the air thermometer during the operation, and both are
immersed in a bath of a fused salt whose melting point is con-
siderably below that of the substance under investigation. Hence
the operation of determining a high melting point by this method
is perfectly analogous to that usually adopted in determining
ordinary melting points lower than the temperature of boiling
mercury.

The air thermometer is simplicity itself. It consists of a
spherical platinum bulb of about 25 c.c. capacity, from which
rise parallel to each other two relatively long capillary tube.s,
also of platinum. One of the tubes passes down into the
interior of the sphere, almost touching the opposite inner sur-
face, while the other only just pierces the envelope. Both are
bent at right angles at their upper extremities, in opposite
directions. In order to eliminate all errors due to the capillary
tubes a compensator is also employed, consisting of a long
capillary U-tube of the same bore and bent at right angles at
the extremities, so as to form an exact counterpart of the
capillary portion of the air thermometer. The small tube con-
taining the substance is firmly fixed by means of stout platinum
wire so that its lower portion is in close contact with the
sphere ; the walls of the tube are of the same thickness as those
of the sphere. The salt employed for the purposes of a bath is
contained in a capacious platinum crucible, supported over a
table furnace in a miniature basket of platinum gauze. One of
the capillary tubes of the air thermometer is ready to be con-
nected with an apparatus for generating pure carbon dioxide,
and the other is attached to a gas-measuring burette similar
to the well-known Schiff nitrogen apparatus, but some-
what narrower, and surrounded by the outer tube of a I.iebig's
condenser, through which a stream of cold water is continually
passed. This arrangement enables the air to be collected and
measured in the proximity of the furnace. The measuring

NO. 131 I, VOL. 51]

burette is filled with a concentrated solution of caustic potash.
The temperature of the water-jacket is measured by a thermo-
meter immersed in a small accessory reservoir, through which
the water passes immediately after leaving the jacket. A very
simple device has been adopted for determining the exact
moment when fusion occurs. Before the experiment the little
test-tube is heated until the substance melts ; a fine platinum
wire, furnished with a thickened end, is then inserted in it, and
allowed to become fixed by the solidification of the substance.
The fine wire is then passed over a pulley some distance over-
head, and the free depending end is attached to a weight ; just
below the weight a bell is hung.

When everything is ready for the actual operation of deter-
mining a melting point, the salt in the crucible is fused, the
lower part of the air thermometer and its attached substance-
tube are inserted in the bath of liquid, as is likewise the com-
pensator, connection with the measuring burette is made, and
the carbon dioxide apparatus is arranged to be delivering the
pure gas. When the temperature of the bath at length attains
that of the melting point of the substance, the portion of the
latter in immediate contact with the walls of the platinum tube
fuses, and instantly the wire is released, and the weight falls
and strikes the bell. The moment the sound is heard, connec-
tion with the carbon dioxide apparatus is established, and the
air contained in the thermometer is displaced and driven into
the measuring burette. The compensator is similarly treated,
and the quantity of air which it contained deducted from that
contained in the thermometer. From the resulting volume,
together with the knowledge previously obtained concerning
the capacity of the thermometer and compensator and the known
expansion of air, the melting point is obtained by a very simple
calculation.

Four groups of interesting results have already been obtained
by use of the new method, indicating the dependence of the
melting point upon atomic weight. They are as follows :

Melting q , Melting

point. point.

Salt.

Potassium chloride
Potassium bromide
Potassium iodide

Sodium chloride
Sodium bromide
Sodium iodide

800 o
7220

684- 7

815-4

7577
661 '4

Potassium iodide
Rubidium iodide
C.vsium iodide

6847
641-5
62 1 'O

Calcium chloride 8o6'4
Strontium chloride 832 o
Barium chloride 9218

It will be observed that in the halogen salts of both sodium
and potassium a diminution of melting point accompanies a rise
in the atomic weight of the halogen ; also that a lowering of the
melting point accompanies a rise in the weight of the metallic
atom in the case of the iodides of the alkali metals potassium,
rubidium, and cxsium, while the reverse occurs with respect to
the chlorides of the alkaline earthy metals calcium, strontium,
and barium. Whether there is rise or fall of the melting point
with ascending atomic weight, however, the salt of intermediate
molecular weight invariably exhibits an intermediate melting
point. .\. E. Tl-tton.

SCIENCE IN THE MAGAZINES.

T^HERE are very few articles on purely scientific subjects in
•*■ the magazines received by us this month. Apparently
the magazine-reading public thinks a scientific pabulum un-
suitable for Christmas reading ; or is it that men of science are
too deeply engrossed in their researches to cultivate the art of
writing interestingly upon the wonders of n.iture ? Literary men
frequently play fast and loose with natural phenomena and laws,
and are often pilloried fordoing so ; but, on the other hand,
many men of science do not pay due regard to the literary
polish which is essential to an attractive style.

The first number of the Fortnightly under the new editor,
Mr. W. L. Courtenay, contains two articles of interest to our
readers, one on " .\ True University of London," by Mr.
Montague Crackenthorpe, and the other on "The Spread nf
Dijihtheria," by Dr. Robson Roose. Mr. Crackenthorpe deals
broadly with the whole question of the expediency of establish-
ing in London a University which shall teach as well as examine.
He defines the work of a true metropolitan University as follows :
(l) To do the work of the higher teaching by its own pro-
fessorial staff, and to superintend .and aid its being done by other
educational agencies in the metropolis. (2) To examine and to

162

NA TURE

[December 13, 1894

grant degrees, but to grant them as a mark of success in regular
and systematic courses of study, rather than in the display of
hastily acquired, and, therefore, ill-digested knowledge. (3)
To stimulate scholarly and scientific research by means of well-
eqnipped libraries, laboratories, and other like apparatus, and
by the institution of public lectures of an advanced character,
like those of the Sorbonne and the College de France. The
scheme drawn up by the Gresham Commissioners satisfies most
of these rtquirements, and a dens tx machina in the shape of a
Statuior)' Commission is all that is wanted to establish it.

So much attention has recently been given to the new treat-
ment of diphtheria, that Dr. Roose's sketch of the history of the
complaint, and the circumstances which tend to promote its
spread, comes very opportunely. His description of the measure-;
calculated to check the prevalence of the disease, and of the
remedy lately introduced, is clear and concise, whilst the follow-
ing statement, though commonly known in the scientific world,
will remove the misapprehension that exists in the minds of a
large section of the general public ;^"L6ffler and Klebs dis-
covered the microbe of diphtheria, and studied its life-history ;
Roux and Versin demonstrated that the bacillus was capable of
evolving toxic material, and Behring crowned the edifice by
discovering the antidote."

.■\n address hv Prof. G. \V. Prothero, on " Why should we
learn History ? " contained in the National, would at first hardly
seem to be a subject for comment in these columns. There is,
however, much in the address worth noticing here, for Prof.
Prothero shows that history, if not strictly speaking a science,
may be taught in a scientific way. Let us briefly state his
argument. There are many gaps in history, but in every
science there is a lack of information on certain points. Evtn
astronomy, the most exact of the sciences, has its dark spots,
and there are shady places in evolutionary biology. Thus, so
far as imperfection of knowledge goes, history and science only
differ in degree. A greater difficulty, perhaps, is that the his-
torian cannot employ experiments either to discover facts or to
test observations ; but here again it .vuffers in company with
geology and other branches of natural knowledge concerned
with the past. History is therefore not disqualified from being
a science because it is not experimental. The infinite variety
and extent of historical phenomena, and the presence of the
human element are, however, "obstacles which, it must
be allowed, check history on the threshold of science. If
indeed the term science is to be restricted to the knowledge
and application of general laws — if that alone is science which
can foretell with certainty the occurrence of certain results — if
science deals with no phenomena but such as can be exactly
weighed and measured — then history is not a science at all.
But this is surely lo restrict science within too narrow limits.
All sciences are not equally exact or equally capable of general-
isation. . . . There jis, in fact, a regular gradation from the
sciences of abstract reason and mathematical formula;, through
the phenomena of the inanimate and the animate world to the
world of man." But, pa^e Prof Prothero, if history be
granted a place among the sciences, it must be scientific in the
ascertainment of its facts. Take the Black Death as an illus-
tration. The vague and exaggerated statements of certain
chroniclers of its ravages may be taken as evidence, or the
more laborious process of searching the registers of the time
may be explored. The difference is that one of the ways is
scientific, while the other is unscientific. In the drawing of
conclusions, also, "there is the same distinction between scien-
tific and unicienlific work as there is in the ascertainment
of historic facts. For instance, Buckle, in illustrating his
theory that national character depends largely upon food,
attributes the weakness of the Hindoos to an almost exclusive
diet of rice. A striking but misleading generalisation, for, as
Sir H. Maine has pointed out, the great majority of the
Hindoos never eat rice at all. . . . There is, then, a scientific
way as there is an unscientific way of studying history. If
treated one way, its results are guess-work and delusion ; if
treated another way, if industry, reason, and sober judgment
are brought to bear, its results are in many cases matter of
certainty, in many others matter of at least high piobability.
And, if we except the science of mathematics, what more can
be said of any science I" The main object of Prof. Prothero's
address was to show that historical study exerts considerable
influence upon the mind and character. Tliii is certainly the
caje, and if the student is trained on the lines indicated in the
foregoing, intellectual results of the highest oidtr must fullow.

NO. 1311, VOL. 51]

The great landslip which caused the formation of the Gohna
Lake, Gurhwal, in the central Himalayas, has led Mr. W. M.
Conway to write on " .Mountain Falls " in the Contemporary.
This caia<trophe, however, is only used as a peg upon which
to hang an account of the great .\lpine landslip which buried
part of the village of Elm, in Canton CKarus, thirteen years
ago. The Contemporary also cont.nins a metaphysical article
by Emma Marie Caillard, in which cosmic and ethical pro-
cesses are discussed, and Prof. Huxley's opinions on evolution
and ethics are criticised. Prof. Huxley is also involved in a
paper on religion and science, contributed by .■\. J. Du Bois to
the Century. Another article for abstract philosophers is Prof.
Seth's second paper on " A New Theory of the .Vbsolute."

Sir Robert Ball contributes to Good Words another of his
interesting — albeit superficial— papers on gre.it astronomers,
the subject being Sir John Herschel. Chaml'ers's jfouiihil con-
tains the usual complement of chatty articles, among which we
notice one on smoke absorption, descriptive of Colonel Dulier's
patent system of removing the soot and sulphurous acid from
the products of combustion, by treatment, before passage into
the chimney, by both steam and water ; and another on remark-
able hailstorms.

A passing reference will suffice for the remaining papers on
scientific topics. The result of prematurely releasing a chrysalis
from its cocoon, a subject on which we published a letter by
Dr. L. C. Jones in our issue of November 22 (p. 79), serves
Mr. W. C. Wilkinson as the theme of a poem in the Century.
St. George Mivart writes popularly on "Heredity" in the
Humanitarian, his paper dealing chiefly with Prof. Weismann's
speculations. A posthumous paper of Richard Jefferies'
appears in Longman's Afa^uzine, and Mr. Phil Robinson con-
tributes a facetious paper on rattlesnakes 10 the English Illus-
trated. In addition to the magazines and reviews named in the
foregoing, we have received Scrilner, CasscU's, and the Sunday
Magazine : but these do not contain any articles that can be
commented upon here.

A^

OYSTER CULTURE ON THE IVEST COAST
OF FRANCE.

T the request of the Lancashire Sea-I"isheries Committee, I
spent some time, last June and July, in investigating the
various methods of shell fish culture in use along the western
coa^t of France from .\rc.ichon in the south to Brittany in
the north. There can be no doubt that there are extensive and
flourishing shell-fish industries along the French coast, and one
is struck very forcibly with the admirable manner in which the
people seem to make the best of unfavourable conditions, and
to take full .advantage of any opportunity given lo them by
nature. Few places on any coast could look more desolate and
forbidding than the vast mud swamps of the Bay of .\iguillon,
and yet by means of the " bouchot " system many square miles
of this useless ground have been brought under cultivation, and
an industry established which supports several villages. Then
again, the neat little enclosures along the beach at many places,
carefully tended by the owners at low tide, remind one con-
stantly of market gardening, ami enforce the truth of the iden,
long familiar to the biologist, and ncnv beginning to be more
generally recognised, that the fisherman should be the farmer,
not the mere hunter of his fish, and that aqui-culture must be
carried on as industriously and scientifically as agriculture.

In addition to industry and care on the part of the fisher-
folk, women as well as men, the success of the shell-fish
industries in France is largely due to the encouragement and
wise assistance of the Government, especially in the regulation
of general oyster-dredging and the reservation of certain grounds
for supplying seed. The practical question — and one of enor-
mous im|.orlance— is : Is there anything special in the condition;
in France, either of the land or of the water, which woul.l
render their methods inapplicable to our more northern shores t
I do not believe that the question can be satisfactorily and
finally answered uiiiil some experimental cultures on a fairly
laige scale have been tried; but a consideration of the details
and results of the French melhoils will at least give us some
idea of which experiments are worth trying, and of the localities
which might be cultivated with most prospect of success.

I AbMraclcfarepor .yrrof. «'. A. HcrJnan, ' .R.S ,10lhc Lancashire
Sea-Fi»hciic5 ConimiUcc,

December 13. 1S94J

NATURE

16:

The leading characteristics of French oyster culture are (i)
that the whole is under the regulation and supervision of the
State, concessions of ground being given to individuals or
companies {e.g. at about 30 francs the hectare at Arcachon)
for the purpose of forming oyster "pares"; (2) that certain
grounds are set aside or preserved as banks of breeding oysters
to supply the spat ; and (3) that the whole process of raising
the spat, and rearing and latlening the oyster, is not carried on
at one locality, but is subdivided and specialised, spat-production
taking place best at one locality, such as Arcachon, and fat-
tening for market at another, such as Marennes.

Two species of oyster are cultivated. Osti-ea eJiilis, the ordi-
nary rounded flat oyster of northwest Europe ; and O. aiigulata,
the elongated Portuguese oyster. The latter, although increasing
in numbers in some places, and becoming of considerable com-
mercial importance, is not so highly thought of as is Ostrea
ediilis.

There are now only two places on the coast of France where
spat is produced in sufficient quantity to be of commercial
importance. These are Auray, in the north, and Arcachon, in
the s juth, and these two localities supply all the other oyster
culture centres in France, and even export to other countries.
One merchant I met at Arcachon told me that he had already
sent eleven millions of oysters to London that season.' I
visited in all about ten different oyster-culture centres ; but as
several of these showed nothing special, they need not be
mentioned. The arrangements for the caplure and rearing of
spat were best seen at Arcachon, and for the further rearing
and the fattening of the adults at La Tremblade and Marennes
on the estuary of the Seudre. At .\rcachon I was fortunate in
enj )ying the hospitality of the excellent Biological Station,
which was established nearly thirty years ago by La Socicte
Scientifique d'Arcachon, and which was made use of by Paul
Bert in 1867 for his observations on the physiology of marine
animals.

.'\rcachon presents remarkable facilities for the study
of shallow-water marine forms, and is of great interest to the
biologist, as well as to the ostreiculturist. Its vast inland sea
<lJassin d'Arcachon), which is about So kilom. in circumference,
contains at high tide about 15,000 hectares of area, and is, over
the greater number of the channels, about $ to 10 fathoms
in ilcpth, while two-thirds of the whole area dries at low tide,
in the middle of the "bassin," and north of the town of
.■\rcachon, is a small island. He des Oiseaux, and on the shores
of this, and on various other fiat sh.illow parts which are
expo.-ed at low tide, and which are called "cra.ssats," are
situated the oyster " pares." Some of these areas are reserved
by the State for the purpose of producing spat, a wise pre-
caution, although some of the parqueurs think the State reser-
vations unnecessary, as there are so many adult oysters over the
ground that plenty of spat is sure to be produced. Certainly
during the time of my visit, which was just when the free-
swimming embryos were settling down, the water over the
pares seemed to be swarming with them, and the spat was
making its appearance over all sorts of suitable submerged
objects. The summer of 1S93 **5, however, a particularly good
season, which the parqueurs attributed to the great heat.
Trobably calm weather and absence of rain during the critical
period when the young oysters are free-swimming, and then
settling down, h.as as much to do with a heavy fall of spat as
the actual temperature.

The oyster reproduces at Arcachon between May and the
beginning of July, and the young animal leads a free swimming
existence for about a week before settling down as spat. The
paiqueurs examine carefully the condition of the spawn in the
old oyster, and at what they consider to be the proper time
(generally about the end of June) for catching the deposit of
spat, they place their "collectors" in position. It is of
importance that the collec.ors should not be put in the water
too soon, as they are liable to become coated with slime and
sediment, which will prevent the young oyster spat (" naissain ")
from adhering. The collectors are crates ("gabarets" or
"ruches") of earthenware tiles, coated with a limy cement

' Two-year olds, measuring 5 to 6 cm. across, cost at the rate of ij fr.incii
fivr iooo,_ and somewhat older ones, measuring 6 10 7 cm., 25 francs per 1000.
These prices include packing and carriage as tar as Bordeaux, where they
meet tlic steamer. On an average only 1 per cent, die on the journey. From
the middle of March to the middle of .^pril is the best time to send young
oysters for stocking purposes to England. Before that it is liable to be too
culd in Eni^land, and later it is too hot in Arcachon for transportation to be
effected safely.

NO. 1311, VOL. 51]

which gives them a whitewashed appearance. The tiles are
like ordinary roofing tiles, about fourteen inches long by six
inches at one end and five at the oiher, and half an inch in
thickness. The cement with which they are coated is made of
lime mixed with sea-water and a certain amount of sand, so as
to form a creamy paste. Different proprietors use slightly
different proportions of lime and sand. The process of coating
(" chaulage") adds from one-sixteenth to one-eighth inch in
thickness to each side of the tile. It has to be done with
some care, so that the limy layer may be of the right nature,
sufficiently strong and adhesive, and yet readily detachable w hen
the time for "detroquage" comes, so that the young oysters
may be removed from the tiles without injury, and without
the necessity of breaking up the tiles, as used to be the case.
By the present method the little oysters and film of cement can
be flicked off rapidly by a skilled hand with a square-ended
knife, and the tiles preserved for use again the following year.
.■\ dozen or more millions of these tiles are probably employed
each year at Arcachon. The prepared tiles are arranged in
alternating rows lengthways and breadthways inside cases made
of strips of wood, so that the water may flow in readily between
and around them. The cases of collectors I measured were
about 6 feet x 2 feet and 3 feet in height, each holding 120
tiles arranged in ten layers. The alternating arrangement of
tne layers is intended to break up the currents of water as the
tide runs through the "ruche," form eddies, and so give the
young oysters a belter opportunity of affixing themselves to the
tiles. The tiles are all placed with the convex surface upwards,
as it ii very important that there should be as litile opportunity
as possible given for the collection of any fine sedimen; in
which the young spat might be smothered. The arrangement
of tiles above described is now considered the best at Arcachon.
Various other arrangements have been tried, and may be suited
to special conditions of bottom or depths of water.

I was very fortunate in seeing some of the tiles just after the
young oyster spat had been deposited, and photographed such a tile
covered thickly with the minute amber-coloured specks. There
may be several hundred such young oysters on one side of a tile.
During my stay at Arcachon I found that the temperature of the
water varied from 74'F. tooverSo'F., and the specificgravity from
I 022 to I 024. However, it is known that no such high tempera-
tures are really required for spat production, since, e.^:, Captain
Dannevig has had an abundant deposit of spat in his pond near
Arendal in Norway, where the July temperature of the water
was only 63' F. To compare these with our own district, we
find that in the same week of July 1S93 'he water off the south
end of the Isle of Man was on the average about 60= F. with a
specific gravity ranging from I 025 to I 026, while shore pools
near the Biological Station at Port Erin, comparable as to ex-
posure with the oyster pares at .\rcachon, reached as hi^h a
temperature as 76' F. Dr. Bashford Dean ' and other authori-
ties state as their opinion, that a low specificgravity is necessary
for a good deposit of spat, but there is no unanimity on this point
amongst the practical men at Arcachon (some of whom are keen
observers, and are in the habit of taking the temperature and
specific gravity).

After removal from the tiles, those young oysters which are
not sold to "cleveurs" away from .Vrcachon are kept for
another year or two in the pares. They are placed at first in
flat tiays having a floor and ltd of close galvanised wire netting,
of about half-inch mesh, and these tiays ("ambulances" or
"caisses ostreophiles") are placed between short posts in the
water on the oyster pare, so that the tide can run freely through
them, supplying the oysters with food and oxygen. They measure
about 6 feet by 4, and are 6 inches deep. They serve to keep
the young oyster, during the early period of its life, out of the
sediment, and they also protect it from its numerous natural
enemies, such as the starfishes and crabs, which manage to suck
or pick out the soft body, and whelks, such as Ftirfura, A/urex
and Nassa, which can bore a hole through the shell. The
ambulances are constantly looked after by the oyster men and
women, who come at low tide, when they are exposed, open the
lids, and pick over the contents, removing enemies and impuri-
ties which may have got in, taking out any dead oysters, and
rearranging those that are left, so that all may have a fair
chance of obtaining food and growing normally. The young
oysters grow rapidly in the ambulances, and soon have to be
thinned out. The larger ones are removed, and if large enough
are thrown into the open area's of the pare. In this way, by

^ Various import.-uitJpapers in Bulletin U.S. Fish Com.nission.

104

NATURE

[December 13, 1894

thiniiing out, rearranging, and adding fresh supplies, relays of
young oysters in their first year may occupy the ambulances for
eight months, although an iadividual oyster may only be in for a
month or so.

Eventually all the oysters not sold to eleveurs get trans-
ferred from the ambulances to the open rectangular areas,
like little fields, which make up the rest of the pare. The low
banks bounding these areas are formed of two parallel rows of
close set vertical bunches of the local heath, Erica scoparia,
with the space between, a foot or more wide, filled in with masses
of a tenacious clay obtained from the He des Oiseaux. Planks
of wood and stakes, to strengthen the boundary, are also used in
places, and at one corner a sluice is formed, so that the water at
low tide may either be retained to a depth of 6 or S inches, or
allowed to run off as required. About one million oysters can
be accommodated in each little field, which is about at the rate
of 125 to the square metre. Going thoroughly over a pare,
partly in a boat and partly by wading, gives one an excellent
idea of the extensive and profitable system of aquiculture
practised at Arcachon.

Between neighbouring oyster pares, and surrounding the
" concessions " of the various proprietors, run lanes of water
about 4 metres wide. These give ready access to the pares, and
can be traversed by the long gondola-like boats of the par-
queurs. The lanes are bordered by rows of tall saplings with
bunches of twigs left on. These are called "pignons." They
keep waving in any slight breeze, and give a characteristic ap-
pearance to the scene. The oyster men declare that they are of
use in frightening away fish, and especially the voracious ray
Myliol'Otis, which might otherwise do great damage in the pre-
serves. Possible depredatioiis of another kind are guarded
against by the "pontons," or large barges, moored at the
corners of the pares in which the " gardes des pcches " live.

Great numbers of the oysters bred and reared through their
early stages at Arcachon are sent to Marennes and La Trem-
blade, in the flat district on both sides of the estuary of the
Seudre, to be fattened in a /i;7V </V/eTa^f, and "greened" by
feeding upon the diatom Navicula fusifcrnns, var. ostreaiia.
Wide canals from the estuary lead the sea-water inland, and
supply the numerous " claires," which are merely shallow arti-
ficial ponds excavated in the clay and marly soil. In spring and
early summer the muddy floor of the claire undergoes a good
deal of preparation by digging, cleaning, draining, and exposure
to sun and air, in order that later on, when sea-water is re-
admitted, at first in small quantity, it may be in what has been
found by experience the most favourable condition for the
growth of the desired kinds of lower algse. These soon cover
the floor with a dense green growth, which the eleveurs recog-
nise as being of great importance to the nutrition of the oysters.
Samples of the growth which I collected from the bottoms of
several claires consisted of Ctadophora flaveicem and C. cxpaina,
along with Spiruliiia leniiiisima and a l.yiigi'ya and little tufts
of Calolltri.x, while a more detailed examination with the micro-
scope shows that these plants are teeming with small animals
and other forms of life, and nearly everything is covered with
innumerable diatoms. Probably the larger green algcc, thought
so much of by the eleveurs, are only of importance in oyster
culture in providing points of attachment and shelter or favour-
able environment for the microscopic forms of life, and especi-
ally for the diatoms. It is well known that diatoms form a most
important constituent of the food of oysters, and that the
greenish blue tint of the celebrated Marennes oysters is due to
the presence in the claires of enormous quantities of Na: icii'it
/iiii/o) ini>,v»r, cs/>rar:\i, upon which the oysters feed. This
form is found in our own fishery district in the estuary of the
Dee (and probably elsewhere), although not abundantly ; but it
is prubable that there are various other allied diatoms that
would do equally well for rearing and fattening oysters on, and
as a matter of fa':! the examination of the contents of an oyster's
stomach shows that the foo<l consists of a number of different
kinds of diatoms as well as other minute organisms.

Altogether, all the evidence I was able to collect shows, I
think, that the bottom of a claire i^ teeming with microscopic
life, and that it is probably this rich feeding a/oni- which is
necessary in order to bring the oysters, in a very short period —
a few weeks usually, sometimes ten days or a fortnight is
sufiicicnt— to the desired condition of fatness and flavour. The
autumn and early winter months are said to be the best for
fattening and greening.

I shall have to omit all reference to the industries at Pointe

le Chapus, at the Island of Oleron, at La Rochelle, at Les
Sables d'Olonne, and at I-e Croisic — except a brief explanation
of the basins of " dcgorgement " seen at Le Chaous and else-
where. These are shallow tanks, high up on the beach, with
smooth bricked or tiled floors, so that they can be kept clean
and free from mud. Their purpose is to enable the oysters
taken fresh from the pares and claires, and which naturally have
some fine mud and food-matters of a decomposable nature cling-
ing to them, both externally and internally, to lie for a few
days in clean water, and so get rid of their impure mud and
excreta before being packed up and sent oft' on a journey. The
oysters also become accustomed in these basins, which can be
emptied and filled with water periodically, to close their shells
and stand prolonged exposure to air.

I do not see that the French shores are, in any important
respects better fitted for shell-fish culture than some parts of
our own Lancashire and Cheshire coast.' The deposits, both
littoral and submarine, are, on the whole, much the same, the
fauna, both macroscopic and microscopic, is scarcely appre-
ciably richer, and although the temperature of the water is
decidedly higher in the south — probably on the average about
10° F. higher in summer — I do not think that that is an essen-
tial condition, so long as the winler temperature of our water
does not get too loiv. It would certainly be necessary, I think,
to keep our oysters completely submerged during the winter
months ; but there are several places in the estuaries of the
Dee and the Ribble, and in the Barrow Channel near Roe and
Peil Islands, where " littoral " cultivation in summer might be
combined with "bedding out" in winter*— somewhat as is done
at present with American oysters in the estuary of the Wyre,
near Fleetwood. As to the other conditions — of bottom, of water,
and of food, several places in the Barrow Channel and in the
Dee estuary seem to me to be well fitted for oyster culture.

T

NO. 13 I I, VOL. 51]

ENDOWMENT FOR SCIENTIFIC RESEARCH

AXD PUBLICATION?

I.

WENTY years ago Prof. Tyndall delivered in New York
and in other cities of this country a series of lectures upon
light. The last of the series was an impressive plea for a more
thorough prosecution of original research in pure science ; and
incidentally, for the need of endowments to maintain it. I was
fortunate in having the opportunity to listen to that remarkable
course of lectures, and to that plea for science. Its impression
has never left me. The impression was the deeper, because
Tyndall set upon it the seal of self-denial. Some 30,000 dols., ^
nearly the entire net proceeds of his lectures in the United
States— money for which he undoubtedly had abundant use in
his own alTairs, or at least in the prosecution of researches in his
own country, and which by all precedent and the example
of other lecturers he would have taken with him —
this he has given to the science of this country,
endowing therewith, in 1885, three scholarships for the
prosecution of original research in physics, one under
the direction of Columbia College, one under Harvard, and a
third at the University of Pennsylvania.

The truths uttered and the example set by this self-deiiying
master have already many times borne fruit. The late President
Barnard, of Columbia College, who was a warm supporter of
Prof. Tyndall when here, bequeathed to Columbia upon his
decease a few years since the sum of 10,000 dols. for the
endowment of another fellowship for the encouragement of
scientific research, upon substantially the same terms as those
of the Tyndall scholarships. In other parts of the country
there have been some other endowments for similar purposes.
In the last year Columbia h.as also received ion,ooo dols., the
munificent bequest of Mr. Da Costa, for the establishment of
the department of biology. Although this bequest is not
primarily for the prosecution of original research, it is not
restricted by hampering conditions, and will to some extent, it
is hoped, admit of a direct and continuous support of the highest
and most advanced studies.

The appeal made by Tyndall has been often renewed by

' This, being a report to the Lanc.-ishire Sea-Kisheries Committee, is only
concerned wilh localities within the Fishery Diitrict.

- Addrets delivered by Mr. Addison Brown, .-it a meeting of the Scientific
Alliance of New Vork. (Reprinted from Smithsonian Kepoft, 1893.)

December 13, 1894]

NA TURE

\b'^

scientific men ; by the heads of universities ; by the presidents
of scientific associations, here and abroad ; and by none,
perhaps, more eloquently than by Dr. Edwin Ray Lankester, in
his address before the biological section of the British Asso-
ciation at Southport, in 1S83.

What shall we say to the call and the examples of such men ?
Was the gift of Tyndall based only upon an idle fancy ? Or
was it the result of a clear perception of a profound truth, viz.
America's need of that money as a stimulus and support to
more scientific research ; the call on him being felt to be the
more imperious, because the need of it was so plain to him,
while obscure to others ; and making his act, therefore, a noble
instance of self-renunciation in an unappreciated c^use ?

"To keep society as regards science in healthy play, " he
says, " three classes of workers are necessary :

"(l) The investigator of natural truth, whose vocation it is
to pursue that truth and extend the field of discoveryfor truth's
own sake, without reference to practical ends.

"(2) The teacher, to diffuse this knowledge. . . .

" (3) The applierof these principles and truths to make them
available to the needs, the comforts, or the luxuries of life. . . .

"These three classes ought to coexist and interact. The
popular notions of science . . . often relate, not to science
strictly so-called, but to the application of science."

The great discoveries of scientific truth, he continues, are
"not made by practical men, and they never will be made by
them ; because their minds are beset by ideas which, though of
the highest value in one point of view, are not those which
stimulate the original discoverer. "

In a chance conversation, a few weeks since, I received a
confirmation of these words, so direct and unexpected, that it
may bear citation. I was talking with an electrical expert who
had made several very interesting and important inventions. I
asked him of how much importance he conceived that the
scientific men of the closet, thejoriginal investigators, so-called,
had been in working out the great inventions of electricity
during the last fifty years — the telegraph cables, telephones, the
electric lighting, and the electric motors ; and whether these
achievements were not in reality due, mainly, to the practical
men, the inventors, who knew what they were after, rather than
to the men of science, who rarely applied their work to prac-
tical use ?

"Not at all," he said, "the scientific men are of the utmost
importance ; everything that has been done has proceeded upon
the basis of what they have previously discovered, and upon
the principles and laws which they have laid down. Now-a-
days we never work at random. Look at that electric light \
Of the energy expended in producing it, only 7 per cent.
appears as light ; the rest, 93 per cent, is wasted, mainly in
heat. We are all now trying to prevent this enormous waste.
I want to reverse that proportion ; but if I can reduce the waste
to only 33 per cent, a patent of my invention will be worth
millions of dollars for its economy in production. In seeking
this we do not work at random. I go to my laboratory ; study
the applications of the principles, facts, and laws which the
great scientists like Faraday, Thompson, and Maxwell have
worked out, and endeavour to find such devices as shall secure
my aim."

This is but an expression, in another form, of what Tyndall
said twenty years ago ; " Behind all our practical applications
there is a region of intellectual action to which pr.actical men
have rarely contributed, but from which they draw all their
supplies. Cut them off from that region, and they become
eveniually helpless."

What is true in one department of natural science is, I appre-
hend, equally true in all. The practical men do not work at
random, but upon the basis of what scientific research and
publication have previously put within their grasp.

It is evident, therefore, that not only the advancement of know-
ledge itself, but all possibility of any continuous advance in those
great improvements which are to mitigate the sorrows, and promote
the health, the conveniences, and the comforts of men, is vitally
dependent upon the progress of scientific research. In recent
years how marvellous have these improvements been ! Besides
those that are most common and familiar to all, what miracles,
almost, have been achieved through the photograph, the
spectroscope, the microscope ; by the discovery of the sources
of fermentation and of putrefaction ; by the discovery of an-
esthetics and the application of antiseptic methods in surgery,
and in the treatment of other lesions I These latter discoveries

NO.

131 I, VOL. 51]

alone have ameliorated beyond expression the sufferings of
man ; they save more lives than war and pestilence destroy,
surpassing even in that regard the safety lamp of Sir Humphrey
Davy — an invention which at the time it was made, was said
to have exceeded every previous discovery as a means of saving
human life, except, possibly, inoculation for smallpox.

This vital relation between the advancement of knowledge
and the welfare of man furnishes an all-sufticient reason for the
continuous and never-ending prosecution of original research.
Of necessity the original work of discovery must always lead ;
that must always precede the practical applications. The
necessity for such research must therefore continue so long as
science and human society endure. As there is no limit to the
advance of knowledge, so there can be no limit to the benefac-
tions it is capable of conferring upon mankind. The more rapid
the advance, the more speedy the enjoyment of its fruits. In
this relation alone the need of ample provision for scientific
progress is one that addresses itself equally to the nation, to the
State, to philanthropists, and to all who would advance the
welfare of man on the broadest and most enduring lines.

How shall such research be maintained and extended ? The
investigator of pure science does not work for profit. His dis-
coveries are not marketable. The law allows no patent upon a
principle of nature or the discovery of a new truth. Newton
could not patent the law of gravitation, nor Volta the galvanism
of the voltaic pile ; nor Ehrenberg and Schwann the discovery
of the widespread influence of bacteria ; nor Faraday, nor Henry,
elect ro-magnetism ; nor Joule, his correlation of forces; nor
Jackson, his anaesthetics ; nor Lister, his antiseptic treatment ;
nor Koch, nor Pasteur, their discoveries of the bacilli, the de-
struction of which may lead to the cure or amelioration of
terrible diseases. To the practical men and to the inventors,
on the other hand, who apply to the specific wants of men the
truths and principles which the men of science have made known
to them, the law, in the form of a patent, gives a monopoly of
from fourteen to twenty-one years. They thus obtain, as a rule,
a reasonable, and, in some cases, even an excessive, pecuniary
reward. In this country alone nearly 500,000 patents have been
issued ; they are increasing at the rate of about 25,000 per
year. In the extreme multiplication of patents affecting a
large part of everything we use, the whole world, it might
almost be said, is p.aying tribute to the inventors and practical
men ; while to the original discoverers, who have made so much
of all this possible, there is no promise of pecuniary reward.

This is not said by way of complaint. In the nature of
things it is scarcely avoidable. The aims, the motives, the
methods, and the genius of the two classes of minds are and
ever must be widely distinct. Original discoverers cannot be
turned aside from their special work to become mechanics and
inventors without infinite loss. Prof. Henry had one form of
the electric telegraph in actual use some years before Morse
conceived it.' But how great would have been the loss to
science, without any corresponding gain, had Prof. Henry in
1S30 turned away from pure science to do the subsequent work
of Morse in adapting the telegraph to common and valuable
use !

Research in pure science can never be made a self-supporting
pursuit. It can never, therefore, be carried forward broadly,
and continuously, and effectively, except through men sustained
by some form of stipend or endowment. Occasionally, it is
true, men of independent fortune, like Harvey, and Darwin,
and Lyell, and Agassiz, have devoted themselves to original
research upon their own means, and have accomplished most
important results. But these instances are rare. Many other
persons, too, with aptitudes and tastes for research, though not
following a scientific career, have carried on private researches
in the intervals of leisure stolen from the exacting demands of
professional or business life ; and these have, in the aggregate,
added no small amount to the common stock of knowledge.

It is no disparagement, however, of these subordinate workers
to say that nearly all the great discoveries, ana nearly all the
great advances along the lines of knowledge, have been achieved
by men who in the main have devoted their lives to the work,
and have been supported through institutions or endowments
which made this devotion possible. Government appointments,
professorial chairs, or salaried positions in scientific institutions
of some kind, have been and must continue to be our chief
dependence. And it is manifest that these can only be main-
tained by Government aid, or by the bounty of private in-
1 " Smithsonian Report," 1S7S, pp. 159, 262

i66

NATURE

[December 13, 1894

dividual^. The former is mainly the European system ; the
latter, in the main, is ours. There, universities are founded by
the Goveniment ; here, chiefly by the people.

In Germany there are twenty-one universities maintained by
the Government. In each of these, as Dr. Lankester states,
there are five independent establishments in the department of
biology alone, viz, in physiology, anatomy, pathology, zoology,
and botany. At the head of each of these establishments there
is a professor, with two paid assistants, makirg altogether about
300 for biological research in Germany ; and he estimates about
one-quarter of that number in the same department in England.
In all the sciences, therefore, there would probably be found in
Germany from Soo to looo persons of high scientific attain-
ments, supported by the Government in the universities, who
are regulaily and systematically engaged in the discovery of
new scientific truth. For it is there made both the object and
the duty of the professors of natural science to carry on original
investigations by work in the laboratory. Their positions are
obtained through previous distinction in such investigations,
and it is for this work that their small but fixed stipend is paid
by the Government.

In the College de France, also maintained by the Govern-
ment, there is the same requiremen>, though with a larger salary
to the professors, and with the added duty imposed on them to
deliver to the students about forty lectures yearly upon the
subjects of the professors' researches ; while in Germany the
professors also receive from each student who attends their
lectures, a m.oderate fee, which serves to increase their meagre
stipend, .is well as to stimulate their activity and usefulness.
Under this system, Germany has become the greatest school of
science, and the resort of the whole world.

In this country the opposite system prevails. The colleges
and universities are mainly private foundations, dependent on
private gifts and endowments. The colleges are unwisely
multiplied. All are more or less cramped for money. This
limits the number of professors and assistants appointed for in-
struction, and crowds them with routine work. The result is
that in all but a few colleges, and in these until comparatively
recently, the duties of instruction have left to the professors but
little time or opportunity for the prosecution of original in-
vestigations : and these with but poor equipment and inadequate
means.

In not one of all our colleges and universities, so far as I
have been able to ascertain, is there a single professor>hip
endowed or founded, even in part, for the avowed object of
original scientific research. Instruction, not discovery, is the
only avowed object. It is to the great credit of American pro-
fessors and teachers that, with so much routine work on their
hands, and so little leisure for research, they should have
accomplished by purely voluntary studies so much as is shown
in their contributions to our scientific publications.

To what is said above, perhaps a virtual exception should be
made as respects our astronomical observatories, in which, the
labours of instruction being less, original work has been
perhaps expected, and has been accomplished with most signal
»ucce^s. To some extent this may possibly apply to our medical
schools also. .■\nd in other departments, generally, wherever
time and opportunity have been afi^orded, much original work
has been done by our professors ; some of it of the first class.
This is attested, not to mention living instances, by the work
of Prof. Henry at Princeton, Dr. Torrey at Columbia, Dr.
Silliman at Vale, Dr. Gray at Harvard, and many others that
might be named. In a number of the States, also, and at
Washington, there have been maintained by the State or
nation a number of scientific men, in connection with certain
State or national inti rests, who have accomplished most im-
portant results ; of lhe>e, Dr. James Hall, of this State, is a
conspicuous instance. At Harvard and at other colleges some
noble opportunities for special study have been also provided in
their scientific schools and museums ; notably in the zoological
museum, the Jetftrson Physical Laboratory, and the Pcabody
Museum of .\rchieology at Cambridge, and also in the depart-
ment of hygiene at the University of Pennsylvania. Hut in
most of these the great compl.iint is the lack of necessary
(.p i,^r,.^r,ts (o make possible the active advanced woik in
< ivery for which those institutions are designed. In

t!- V Museum there was in 1891 a gift of 10,000 dols.

by .Mrs. Hemenway to establish a po>t-graduate fellowship ;
and also a gill of like amount by Mr. Wolco't, for the general
support ol the museum's wjik. New Vork also has wiihin

NO. T31 I, VOL. 51]

a few years past seen spring up almost as by magic, through the
efforts of a single leading spirit, seconded by other public-
spirited men and women, and by municipal aid, a museum of
natural history that bids fair to stand in the front rank of
scientific opportunities ; but the endowments of fellowships and
professors necessary to make its opportunities available in active
research are as yet wanting.

England holds a position midway between the United States
and Germany. Her scientific men lament her deficiencies.
They are striving to increase their means for scientific work, and
are doing so yearly.

If experience teaches anything, it is that no broad and general
development of scientific work of the first class is possible,
except either through independent establishments for special
work, or else by the university system, in which professors in
science and their assistants are first selected on account of their
previous distinction in original research, and are then appointed
to continue that work, and in the teaching of students, to
transmit to them the zeal of discovery and the true methods of
advance.

It matters little whether the support of the university or of
special institutions for research comes from the Government or
from private endowment, provided the provision is adequate
and constant. The difficulty with us has been, and still is, that
funds are insufficient, the means and equipment inadequate,
and the time allowed to the professors for research insufficient.
Theie has been too much of the schoolmaster, and too little of
the real professor. Too great absorption of the professor's
time in the work of instruction is injurious to both teacher and
pupil. The most stimulating of teachers is he who by daily
experiment is in vital touch with nature — he who brings from
the fires of the laboratory the warmth, the illumination, and
the inspiration of his own researches.

This is now well recognised ; and so far as their means will
permit, the leading colleges are by degrees relieving their
professors of the work of elementary instruction, so that they
may the better prosecute original researches, and at the same
lime become best qualified for the highest work of instruction.
This system will doubtless demand watchfulness and discrimin-
ation. To prevent abuses, regulation and responsibility may
have to be imposed. But it involves the appointment of
additional instructors. It requires added means. And this is
indispensable as a part of the transition of our leading colleges
to the university system. It is indispensable, also, if we are to
have in this country any considerable systematic prosecution of
original research. We must use existing instrumentalities and
existing institutions. And all experience shows that outside of
the few Government positions, and in the absence of special
institutions for research, the professorial chairs arc best adapted
to such investigations. Xo greater service could be done
to science than to make such endowments as should insure
systematic ami continuous research by the professors as a part
of the new university system.

Endowments for the same object, and operating in the same
line, might also take a different form, viz. the endowment of
several professorial fellowships, e.ach, say, of 1000 dols. annual
income ; to be controlled and awarded by some independent
scientific body (such as this alliance might afliord) for distinction
in active scientific investigations, either within the country or
within the State. I know nf no more quickening impulse to
original scientific research than such as would be given to it by
those means.

How backward we have been in this country, through the
lack of proper endowments, in making use of the best existing
opportunities for research, may be illustrated by a single
instance. Some twenty years ago a school was established at
Naples for the prosecution of marine biological research. It is
most thoroughly equipped, and, being a general resort, is the
most advantageous for study in the world. It is maintained by
a charge of 500 dols. per year upon each table occupied, each
occupant being entitled to all the advantages of the institution.
Of these tables, the German States for several years have taken
thirteen ; Italy, eight ; Austria, Russia, Spain, and England,
escli three ; Switzerland, Belgium and Hcilland, each one ; the
United States, until 1S91, none, except one table supported by
Williams College for two years, and one by the University of
Pennsylvania for one year. Prior to that time about fifteen
other American students in all had obtained places at the tables
taken and paid for by other nations. In 1890 this arrange-
ment was I'rohibited l>y the administration of the institution ;

December 13. 1891]

NATURE

167

and the right to a table in iSgi.was secured to Americans,
only through the private benefaction of Major Alex. Henry
Davis, of Syracu5e. For the year 1892 the use of a table has
been secured through a subscription started by the American
Association for the Advancement of S:ience, toward which the
Association itself granted out of its scany funds loo dols. and
was the means, I believe, of procuring the rest.'

We have not, however, been wholly without some such means
of study in this country through the marine biological
laboratories established some years ago at Newport and at
Wood's Holl, by Prof. Alex. Agassiz. The former has been
now enlarged so as to accommodate eight advanced students,
besides the professor and his assistant." The Johns Hopkins
University also has supplied some opportunities of this kind by
its summer school, formerly at Beaufort ; later, at Jamaica ;
but at present, as I understand, it is without any permanent
location.

Our neighbour, the Brooklyn Institute, has organised similar
investigations, on a minor scale, during the summer months at
different places on Long Island. But what is needed for the
most effective work is suitable endowments for professors and
advanced students, in connection with an adequate biological
laboratory, such as the Newport one enlarged might afford,
equal in means and equipment to that at Naples, or at least to
that recently completed, largely through private enterprise, at
Plymouth, England.'

{To be continued.)

SCIENTIFIC SERIALS.

Bulletin de f Acadimie Royale dc Belgii]iie, Nos. 9 and 10. —
On the conversion of black mercuric sulphide into red sulphide,
and OR the density and specific heat of these bodies, by W.
Spring. As a general rule, if a body is capable of existing in
two allotropic states with different densities, it is possible to
convert the lig hter into the heavier kind by compressing it to the
higher density, the pressure depending upon its compressibility.
Sometimes this conversion is only possible above a certain
"critical temperature." In the case of the sulphide of mercury
the conversion of the black into the red variety (vermilion)
involves a compression of 9 per cent., and would require a
pressure of 35.000 atmospheres, which is not at present attain-
able. But M. Spring has succeeded in obtaining a new form of
black HgS which only requires 2503 atmospheres. It is
obtained by sublimation of ordinary black HgS in an .Ttmo-
sphere of nitrogen or C0„. Its density is 80395, while that of
vermilion is 8 1587, and of ordinary black HgS 7'6242. A
curious side result of the investigation is that the black sulphide
hitherto known, after being made to expand by heat and then
cooled, takes al>out a day to return to its original density. —
Vapour tension and hygrometric state, by Dr. J. Verschaffelt.
A new hygrometer may be based upon the fact that the hygro-
metric state of the atmosphere may be taken as the ratio of the
vapour tension inside a solution to the highest possible vapour
tension of water at the same temperature, if the tension inside
the solution is equal to that in the atmosphere, i.e. when the
solution does not evaporate or gather moisture from the air.
The ratio mentioned is independent of the temperature, and
hence the humidity is simply a function of the concentration of
the solution. In practice. Dr. Verschaffelt moistens a weighed
piece of blotting-paper with a weighed quantity of a solution of
lithium chloride of known concentration, exposes it to the
atmosjihere, and weighs it again. From the last weight the
"equilibrium concentration " may be calculated, and from this
the humidity with the aid of Dieterici's data for this salt. The
apparatus might be made self-registering.

t See l^ro^ccdittf^s .■liiurican Association .-/. .S". 1891, vol. .\I. p. 449-451.

- Ke/iort ilan'ard Colieee, 1891, p. 182.

3 In his address before the American Association for the Advancement
of Science, in 1891, President Prcscott, referring to this general subject, said:

" To nurture investigation in science is the Kirgcst opportunity before the
American people. Research, systematic and wisely directed, requires good
organisation and strong support, the supporc of many powers. It must have
the support of able and persistent men. It needs the conference of workers,
and the dissemination of knowledge in societies like this. It wants the
interest .-.nd the confi^lence of the public. Itasks and will alwaysobtain the
constant, helpful use of the press. It retiuires distinct provision in cjlleges,
and in the institutions of higher education. It ought to be sustained
expressly by the Government, both in the several States and under the
United States, and sustained on broad and permanent foundations. Still, it
needs private benef.actions. Research is the growth of years. Let it be
the demand of all, and let this call find utterance' everywhere.** — I'rocccd-
ingt Atuctuan .■Issociaiion, 1891, vol. .\I. p. 440.

Bulletin of the American Afniliematical Society, vo]. i. No. 2.
(New York, iMacmillan, November, 1894.) — On the problem
of the minimum sum of the distances of a point from given
points, is the translation, by A. Ziwet, of a paper presented to
the Society at its summer meeting J.Vugust 15), by Prof. V.
Schlcgel (pp. 33-52). This frequently discussed problem (see
references given by Slurm, Cretle 5 Journal, vol. 97), is con-
sidered by the author to offer room for further treatment. He
discusses the best method of investigating the question, and in
the end treats it by means of the simplest methods of Grass-
mann's " .\usdehnungslehre." Prof. Cajori collects a number
of authorities in confirmation of a statement in his " History
of Mathematics" (p. 218), that it is not true that the binomial
theorem is engraved on Newton*s monument in Westminster
Abbey. The latest additional authoriiy for his statement is
contained in a letter from the present Dean of Westminster,
whom Prof. Cajori calls "Dr. Granville" I— The only other
matters are the notes and new publications.

NO. 1311, VOL. 51]

SOCIETIES AND ACADEMIES.

Cambridge.

Philosophical Society, November 26. — Prof. J. J.
Thomson, President, in the chair. — (Jn Benham's artilicial
spectrum, by Prof. G. D. Liveing. Prof. Liveing exhibited
one of Benham's "artificial spectrum tops" (see Nature,
November 29, p. 113), and a variety of discs with figures in
black disposed on a white ground, and with white figures on a
black ground, which, when revolved in a bright light showed
remarkable bands of colour of various shades of red, green, and
blue. The general result of his observations of these discs was
that if a succession of black and while objects were presented
to the eye with moderate, but not too great, rapidity, then,
when black was followed by white, an impression of a more or
less red colour was perceived, while when white was
succeeded by black a more or less blue colour was
perceived. If the succession of black and white was
very rapid the appeaiance presented to the eye was
of a more or less neutral green or drab. The explanation
offered by Prof. Liveing was based on the known facts that the
impression produced on the retina by a bright object remained
for an appreciable time after the light from the object had been
cut off, and that the duration of that impression was different
for different colours ; and on a supposition, which he did not
know to have been as yet verified experimentally, that the
rapidity with which the eye perceives colours was greater for
one end of the spectrum than for the other. From this point of
view the explanation of the blue colour seen when white is
followed by black would be that the impression of blue on the
retina lasts a little longer than that of the other colours ; while
the red colour seen when while succeeds black is due to the
greater rapidity with which the eye perceives red light than that
with which it perceives blue. If, however, the alternations of
white and black succeed each other with sufficient rapidity, the
new impression of a white patch will be produced before that of
its predecessor has vanished, and there will be an overlapping
of impressions, and the sensation will be that of a mixture of
colours, or of a more or less neutral tint. So far as he could
test the theory by his osvn eyes it appeared to him that the
residual impression, left when the light from a white object was
suddenly cut off, was at first green and faded out through a
more or less blue or slate colour. — On a simple test case of
Maxwell's law of partition of energy, by Mr. G. 11. Bryan.

Paris.

Academy of Sciences, December 3. — M. Lnewy in the
chair. — The reduction of alumina by carbon, by JI. Henri
Moissan. The author describes the reduction of pure corundum
by means of his now well-known electric furn.ice. Liquid
alumina is not reduced by carbon ; the reduction only takes
place when the vapours of these substances are carried to a very
high temperature, metallic aluminiuin is then produced and
partially combines with carbon. — Reply to M. Mayer-.Vymar
concerning his defence of .Sa/uiricn as a name for the latest
geological period, by M. A. Pomel.- — \ letter from Prof. K.
Fresenius was read announcing the formation of a German
committee in connection with the Lavoisier monument. The
Academy appointed Prof. Fresenius delegate for this work.
Prof. G. Hinrichs was similarly appointed delegate for the

i6S

NATURE

[December 13, 1894

United States. — On the identity ol the new comet with De
Vice's comet, by M. L. Schulhof^see our Astronomical Column,
December 6, p. 132). — Obser\-ations of the planet B H 1894,
discovered ;by M. Borrelly at Marseilles Observatorj-, Nov-
ember 19, 1S94 ; by M. Borrelly. — tin the distribution of
planets between Mars and Jupiter, by M. E. Roger. A
mathematical paper in continuation of a paper on the same
subject in the previous number. — On quasi alternate permuta-
tions, by M. Dcsiit. Andre. — On the temperature of the electric
arc, by M. J. Violle. The conclusion is drawn, from a
spectroscopic study of the poles and the arc itself, that the
temperature of the arc is generally higher than that of the
positive carbon, and that it increases with the electric
energj- employed. — On the solubility of ozone, by M. I'Abbe
Mailfert. At a pressure of 76 mm. water dissolves two-
thirds of its volume of ozone at 0° C, at 12° about
one-half. The solubility of ozone in water acidified
with sulphuric acid is the same as its solubility in pure
water up to about 20' C. ; more ozone is dissolved by
the acid solution above this temperature. The suggestion is
made that ozonised water might be employed as a disinfectant
and antiseptic. — On the superposition of the optical effects of
different asymmetric carbon atoms in the same active molecule,
by MM. Ph. A. Guye and M. Gautier. For the determination
of this point the authors have used in the present instance amyl
valerate. The ester produced by combining inactive amyl
alcohol with active valeric acid gives [o]t, = -• i oS", the corre-
sponding compound with active amyl alcohol and inactive
valeric acid gives [o]i) = -f 4'26' ; the ester obtained from active
alcohol and active acid gives [o]i, = ~ 5 "32°, while the sum of
the two former is -r 5 ZK^- Theoreti>:ally a better agreement
should be obtained by using the raccmic in place of the
inactive torms ; in this case the sum is 5 '62°. The differ-
ence is probably due merely to experimental errors. —
Experimental researches on the crystallisation point of
some organic substances, by M. Kaoul Pictet. The crystal-
lisation points of a number of organic substances are given, and
the results are embodied in a number of general conclusions
confirming previous work. — On the emission of a saccharine
liquid by the green parts of the orange-tree, by Dr. M. Biisgen.
The author calls attention to the part played by aphides and
similar parasites in the production of saccharine liquids from
plants, and includes the orange-tree among the cases of this
kind. — Osteomyelitis of the inferior maxillary in the kangaroo,
by MM. Lannelongue and Achard —On the action of the toxine
from the pyogenous Staphylococcus on the rabbit, and on the
secondary infections which it determines, by MM. Mosny and
G. Marcano. The loxine does not confer immunity against the
attacks of the living microbe. — Action of high pressures on
some bacteria, by M. H. Roger. Nutable differences were
observed between different bacteria in regard to their behaviour
under pressure. The virulence of the anthrax bacillus was very
much diminished by a pressure of 3000 kgms. — On the dis-
infection of fcecal matter, by M. H. Vincent. At about 16° C.
the disinfection of normal facal substances is brought about in
twenty-four hours by 6 kgms. of copper sulphate per cubic
metre. Eberth's bacillus is destroyed in typhoidal refuse by
5 kgms. per cubic metre, and the cholera bacillus by 3 '5 kgms.
of copper sulphate per cubic metre after twelve hours contact. —
Marine muds and their classification, by M. J. Thoulet.

Berli.n.

Physical Society, November 2. — Prof, du Bois Reymond,
President, in the chair. — The President alluded to the death of
Prof Pringsheim, and drew attention to his important re-
searches on the fertilisation of alga;. — Dr. C. H. Wind gave
a comprehensive review of the researches carried on by Dutch
observers with reference to Kerr's phenomenon. He then dis-
cussed I, orentz's theory, and described the elaborate experiments
made by Sissingh and Zeeman and by himself, which had
yielded results for iron, nickel, and cobalt, which were not
quite in accord with the theory. .Since the other theories as
to this phenomenon, as, for instance, that of Drude, are still
less in accord with experimental facts, the speaker had extended
I.orenlz's theory so as to take into account the results obtained
by Sissingh and Zeeman, and to bring the phenomenon of Kerr
into relation with that of Mall. This extension of the theory
had been accepted by Lorentz, and Dr. Wind is now engaged
nn the inveitigation of certain phases of Mall's phenomenon.

BOOKS, PAMPHLETS, and SERIALS RECEIVED.

Books. — In the Guiana Forest: J. Rodway (Unwin). — The Electro-
Plater's Handbook: ti. E. Bjoney, md edition (Whittaker). — Lehrbuch
der Botanik fur Hochschulen : Drs. Strasburger, Noll, Schenck. aad
Schimper (Jena. Fischer). — Lehrbuch der ZooloRie : Dr. R. Hertwig, Dritie
Auflage (Jena, Fischer). — Climbing in the Himalayas ; Maps and Scientific
Report^ : W. M. Conway (Unwin).— Ottica : Prof E. C^clcich (Milano.
Hocpli).— The Dynamics of Life: Dr. W. R Gowers (Churchill).— The
Planet Earth : R. A. Gregory (Macmillan). — Britain's Naval Power: H.
Williams (Macmillan). — The Warwick Shakespeare. "As you like it," edited
by J. C. Smith (Blackie). — The Teachers Manual of Lessons in Elcmentar>-
Science : H. Major (Blackie). — Handbuch der Stereochemie : Drs. Walden
and BischotT, ii. Band (Frankfurt a.M., Bechhold). — Forty-three Graphic
Tablcsor Diagrams for the Conversion of Measurements in Different Units :
Prof. R. H. Smith (Griffin).— Torpillcs SOches : E. Hennebert (Paris,
Gauthier-Villars).

Pamphlet. — Gehirn und Seele : Prof. A. Forel (Bonn, Strauss).

Serials.— Observator>*, December (Taylor and Francis). — Companion to
Observatory (Taylor and Francis). — Himmcl und Erde, December (Berlin,
Paeiel). — Geographical Journal, December (Stanford). — Natural History
of Plants: Kerner and Oliver, Part S (Blackie).— Yule Tide Annual
(Cassell). — Science Progress, December (Scientific Press).

NO.

131 I, VOL. 51]

CONTENTS. PAGE

Dilettantism and Statistics. IJy Prof. Karl Pearson 145

Water Supply and Water-works 146

Hamilton's Pathology 148

Our Book Shelf:—

Fox : " The Mechanism of Weaving " 149

Atkinson: " Memorials of Old Whitby " 149

Haacke : " Die Schcipfung der Tierwelt " 149

Hutton : " The Vaccination Question," 149

Glaister : "Dr. William Smellie and his Contem-
poraries " 149

Letters to the Editor: —

Dr. Watt's Dictionary of the Economic Products of
India.— W. T. Thiselton-Dyer, C.M.G.,

F.R.S. ; Dr. V. Ball, F.R.S 150

Drift-Bottles in the Irish Sea. — Prof. W. A.

Herdman, F.R.S 151

The Explosion of Gases in Glass Vessels. — Prof.

H. B. Dixon, F.R.S 151

The Kinetic Theory of Gases. — G. H. Bryan; Dr.

J. Larmo.-, F.R.S 152

Pecviliarities ol Psychical Research. — Prof. Karl

Pearson 153

Chronometer Trials.— William E. Plummer . . . 153

Indo-Malayan Spiders. — B. A. Muirhead ■>.... 153

Death-feigning in Snakes.— Gerard W. Butler . . 153
The Alleged Absoluteness of Motions of Rotation. —

A. E. H. Love, F.R.S 153

Gravitation. — Prof. Oliver J, Lodge. F.R.S. . . . 154
Outlines of Quaternions. — Lieut. -Colonel H. W.

L. Hime 154

The Warble Fly. (rilustraUd.) By W. F. Kirby . . 154

Ferdinand de Lesseps 155

Notes [HUiiirateJ) 156

Our Astronomical Column : —

Motion and Magnitude 160

The Recent Transit of Mercury 160

The New Achromatic Object-glass. {Illustrated.) . 160

Ephemeris for Swift's Comet i6c

A New Star? 161

Prof. Victor Meyer's New Method of Determining

High Melting Points. Uy A. E. Tutton .... 161

Science in the Magazines 161

Oyster Culture on the West Coast of France. By

Prof W. A. Herdman, F.R.S 162

Endowment for Scientific Research and Publica-
tion. 1 164

Scientific Serials 167

Societies and Academies 167

Books, Pamphlets, and Serials Received ... 168

NA TURK

169

THURSDAY, DECEMBER 20, 1894.

SIR RICHARD OWEN.
The Life of Richard Oiuen. By his grandson, the Rev.
Richard Owen, M.A. With the scientific portions
revised by C. Davies Sherborn. Also an Essay on
Owen's Position in Anatomical Science, by the Right
Hon. T. H. Huxley, F.R.S. (London : John Murray,
1894.)

THE life of this well-known and eminent anatomist,
written by his grandson, the Rev. Richard Owen,
has been based on such a large amount of material that
" the writer's chief difficulty has been to compress the
biography within reasonable limits." While acknow-
ledging that the art of compression is a difficult one, we
still must express some disappointment at the way in
which it has been carried out in the two volumes of this
biography. For over si.xty years Owen filled a more or
less conspicuous place in the scientific world ; in a large
measure a self-taught anatomist, he at a very rarly age
became a teacher of anatomy to others, with a wondrous
collection of material at his disposal to illustrate his
teaching. In these volumes we do not seem to find
enough about his evolution as a man of science, and
we could, in some measure, have dispensed with many
of the trifling details of his every-day life, which have,
if any, but a passing interest. In the following sketch
we attempt to show but a phase of Owen's character ;
but, in common with all who had any personal know-
ledge of him, we do not overlook, nor can we forget, the
charm of his domestic and cultured life.

Richard Owen was the younger son of Richard Owen,
of Kulmer Place, Bucks ; he was born at Lancaster on
July 20, 1804. His mother was of a Huguenot family
of the name of Parrin, who came from Provence at the
time of the revocation of the Edict of Nantes. He
would seem to have inherited from his father many of
his physical characters, his height and sturdy frame ;
while from his mother came his fondness for music, and
a certain refinement and courtier- like style of manner
which were of some value to him in after-life. Ap-
parently his mental training began early, for we find his
father writing from St. Kitt's to his mother, " that he
was glad to know James (the elder brother) and Richard
came on so well with their studies, and were so atten-
tive," at a date when Richard could not have been more
than three years and a half old. When six years old he
was sent to the Lancaster Grammar School, to Join his
elder brother, a school that will be always associated
with the name of Whewell, the great Master of Trinity,
Cambridge, who received here his early education.
Soon after he had left school, we find him apprenticed
to Mr. Leonard Dickson, of Lancaster, surgeon and
apothecary, and on his death, in 1822, he was transferred
to Surgeon Seed, of the Royal Navy ; and finally, on
Mr. Seed being called upon by the Service, he was com-
mitted to the care of Mr. J. S. Harrison. Matriculating at
'Edinburgh University in October, 1824, he seems to have
attended one winter, and possibly a summer, course of
lectures. In 1S25 he was in London, attending lectures
at St. Bartholomew's Hospital School, and became pro-
NO. 1312, VOL 5 1]

sector for Dr. ."^bernethy. On August 18, 1S26, he was
admitted a member of the Royal College of Surgeons,
London.

To the medical student of the present day, compelled
to attend a five years' course of lectures and demon-
strations, and to pass several examinations, there will
seem something enviable in the apparent ease with which
Richard Owen obtained his qualification ; there was an
incomplete apprenticeship at Lancaster, perhaps a years
course of lectures at Edinburgh, and another year, about
which we have few details, at St. Bartholomew's, and then
he set up as a medical practitioner, and gradually secured
a small practice among the lawyers at Lincoln's Inn
Fields. To those, however, who try to read under the
lines, it will be evident that the abilities and industry of
Owen, about which his mother "so proudly writes, must
have been of no common order. Up in that old tower at
Lancaster — '• Hadrian's Tower, it was called " — after the
first spasm of fright, the particulars of which are so
graphically told us by the Professor himself, the youth of
sixteen must have carried on his anatomical investigations
to such a purpose that we find him, on his visit to
Edinburgh, not only able to detect the defects of the
teaching of anatomy of Prof Monro {terlius), but aole
also to attract the notice of John Barclay, and finally, on
his visit to London, able to act as prosector to Abernethy .
We would have welcomed more information as to how
Owen became an anatomist. Was his worthy master at
Lancaster, who could learnedly descant on certain patho-
logical conditions, an anatomist, or did the "elder
fellow pupil " about whom he writes (who was he ?) help
him in his studies ? Probably wfe will never know, and
yet a knowledge of his doings during these few early
years of study would have helped us to an understand-
ing of the man.

In 1827, through the influence of Abernethy, who at
the time was President of the College of Surgeons,
Owen was appointed Assistant Curator of the College
Museum, under William Clift, and he at once pro-
ceeded to arrange the collections and to write the
descriptive catalogues, the first three parts of which
were published in the course of 1830. Before the
end of 1S27 he was engaged to be married to .Miss Clift,
and after an eight years' courtship they were married in
1S35. William Home Clift had died from an accident in
September 1832, and Owen's place at the College then
became a permanent one. In 1836 he was appointed
Hunterian Professor, and on the retirement of Sir Charles
Bell (in the early part of 1837) from the Professorship of
Anatomy and Physiology in the College, Owen was elected
to the vacant chair. For these latter statements we follow
the text before us ; but is it not possible that there is
some slight confusion here.' Up to about the period
ivhen Sir Charles Bell resigned the Professorship of
Anatomy, the lectures bearing on the Hunterian col-
lections were supposed to have been given in part by the
Professor of Anatomy and in part by the Professor of
Surgery ; but, by a special arrangement, these lectures,
twenty-four in number, were, after 1837, to be delivered
by Owen, as Hunterian Professor, and "the awful first
lecture " was given on May 2, 1837.

For the next twenty years of i iwen's life the scene
was for the most part laid in Lincoln's Inn Fields.

I

I70

NATURE

[December 20, 1894

" ' Mr. Owen ' was put up on our door-plate to-
day. Looks most imposing," records Mrs. Owen,
under the date of July 22, 1S36, and it was in
June 1S56 that he entered upon his duties as Super-
intendent of the Natural History Department of the
British Museum. These twenty years were, perhaps,
the fullest of Owen's life. The boy who had begun his
anatomical studies in Lancaster at sixteen years of age,
was, some sixteen years afterwards Hunlerian Professor,
lecturing before brilliant audiences of grown-up men, and
with material to lecture about such as has seldom fallen
to the lot of any other man. Numerous were the works
published during these years, and numerous were the
honours conferred on him. Fully detailed lists of both,
occupying many pages, will be found at the close of
volume ii. The time was not all spent in tiresome
work ; Owen's social qualities were of a well-developed
order. We are permitted, by his wife's records of their
daily lives, to know of days and evenings spent in gay
and festive scenes.

In chapter ix. we have a fuller account than, we think,
has to this been published about the daring thoughts that
were at one time in Owen's mind (1846) about the zoolo-
gical collections of the British Museum. He calls them
" speculations on a concentration of all zoological illus-
trations— living, dead, exterior, and anatomical— in one
great connected establishment"; but, failing such a
realisation, he would be satisfied if " all the recent and
fossil zoology of the British Museum would come to this
(College of Surgeons). The mineralogy would naturally
be transferred to the Government Museum of Economic
Geology," and " the British Museum would then be left
free for the full extension of the departments which con-
cern intellectual man." The last sentence was unfortu-
nately expressed; and within ten years, Owen's ideas—
possibly affected by lapse of time and change of scene-
had vastly changed. He thought, in 1846, Lincoln's Inn
Fields as central a position as Great Russell Street ;
afterwards, in 1856, though he liked the position in
Great Russell Street well, yet for the sake of space he
went out into the country. Perhaps, in taking note of
this episode, we ought also mention that in 1S48 he
strongly urged on his friend. Dean Buckland, the im-
portance of the great collection of shells, made by Hugh
Cuming, being purchased for the British Museum.

At the close of the first volume there is an interesting
letter, dated July 17, 1854, from Charles Darwin, which
we do not remember to have seen before. He thanks
Owen for his kind appreciation of his work on the Cir-
ripedia. " I got so frightened at the thoughts of all the
seaside species, that I have not illustrated and given in
detail nearly enough my anatomical work, which
is the only part of the work which has really
interested me. 1 find the mere systematic part
infinitely tedious. 1 can, however, honestly state that
all I have said on the males of Ibia and Scalpellum is
the result of the most careful and repeated observation.
If i am ever proved wrong in it I shall be surprised."

On May 26, 1856, Owen was appointed Superinten-
dent of the Natural History Department of the British
Museum, and he entered on his duties on June S follow-
ing. We presume that he resigned his position at the
College of Surgeons at the end of May, as the letter of
NO. 131 2. VOL. 51]

I

the Secretary of the College, forwarding the regrets of
the Council, is dated June 12, 1S56. Lord Macaulay's
letter to the Marquis of Lansdowne, urging that the post
should be made for Owen, was written in February 1S56 ;
so that the one scene of labour was exchanged for the
other almost wiih the rapidity of a transformation scene,
and before the end of June, Owen was examining the
"two collections of Mr. Hawkins— those of Dr. Mantell
and Mr. Koch " — in the British Museum, which in 1S46
he had believed to be so much out of place there. For
the next twenty-seven years the interests of the wonderful
collection were always very dear to him, and no diffi-
culties, no rebuffs, stopped him from carrying out his
plans about them to their uttermost.

Chapter ii. of vol. ii. is devoted to the history of Owen's
connection with the British Museum of Natural History
at South Kensington. This account " is given as nearly
as possible in his own words, the substance being taken
from his address to the British Association at York in
18S1." It would have been well if this chapter had been
revised by some one with a personal knowledge of the
state of things existing in the Natural History Depart-
ment of the British Museum prior to Owen's appoint-
ment, or, failing this, of some one up to the traditions of
the place ; for though, undeniably, space was sadly wanted
for the proper display of the specimens, this department,
as a department, was scarcely " the most neglected
branch of the institution," nor could the condition of
affairs be described as "chaos. ' However, in February
1S59, Owen submitted his views in a report to the
Trustees,asking for space to display the existing specimens
and those that might be expected to come for a genera-
tion. Organised and crystallised forms, all were to be
now included. This report, with plans, was presented to
Parliament by the Trustees ; the space demanded rec|uired
the removal of the collections from Bloomsbury, the lime
had not come for so great a change, and Mr. Gregory,
afterwards Sir William Gregory, here referred to as an
"Irish Member," asked for a Committee of Inquiry,
which, after a pretty vigorous debate on July 22, 1S61,
was granted. In May 1862 there was a second stormy
debate in the House of Commons, led by Lord Beacons-
field, and the Government were refused leave, by a large
majority, to bring in a Bill for the removal of portions of
the Trustees' collections in the British Museum. Things,
however, changed in 1863; Sir William Gregory had
been made Governor of Ceylon (it is difticult to see
what effect this could have had on the matter), and in
June of that year leave was obtained by a majority of 132
to purchase five acres for the required Natural History
building. Between 1880 and 18S3 Owen was engaged
in superintending the removal of the specimens from
Bloomsbury to South Kensington, and at the close of the
latter year he retired from his post, the realisation of his
idea being attained.

When Owen gave up the charge of the Museum of the
College of Surgeons, he also surrendered the Hunlerian
Chair ; he was thus enabled to accept the Lecturersliip on
Palaeontology at the Royal School of Mines, in 1857. He
gave his first lecture on February 26, concluding the course
on April 2. Mrs. Owen notes in her diary, Richard's " de-
sign has been clear throughout in these lectures— to show
the power of God in his creation." Towards the end of

December 20, 1894 J

NATURE

171

the same year he was appointed Fullerian I'rofessor of
Physiology at the Koy.il Institution, so that there was no
relaxation in lecturing work during these years. Owen
was President of the British Association at its meeting at
Leeds in 1857. We also get a glimpse of him at Aberdeen
in 1S59. but can find no trace in these volumes of his
presence at the Oxford or Cambridge meetings of i860
and 1862 ; indeed, even when noticing the publication of
the memoir on the Aye-Aye in 1863, no reference is made
to the remarkable paper read at the Cambridge meeting
on the characters of this mammal as a test of the
Lamarckian and Darwinian hypotheses of the transmu-
tation and origin of species, nor is there any allusion to
the " two pitched battles about the origin of species at
Oxford," nor to Charles Kingsley's well-meant little squib,
published during the Cambridge meeting by Macmillan
and Co., " On the great Hippocampus (Question."

Mrs. Owen, after a married life of nearly forty years,
died in May 1S73. In 1875 Owen refers to his daily task
work becoming tiresome, as well it might to a man past
seventy, but several important memoirs were published
by him between this year and 1885, and in 1S81 he de-
livered a long address to the Biological Section of the
British Association at York, on the new Natural History
Museum ; this was almost his last public address, and it
was delivered with a force and power that reminded his
hearers of his early days. On January 5, 1S84, Owen
was, on his retirement from the post of .Superintendent of
the British Museum, gazetted a K.C.B. He was present
at a meeting of the Linnean Society, at Burlington House,
in May 1888, "to receive a gold medal." The medal
thus alluded to was one of two struck in commemoration of
the centenary of the Linnean Society ; one medal was to
be given to a botanist, and one to a zoologist. The
botanist on this occasion was Sir Joseph Dalton Hooker.
Up to the close of 1S89 he was occasionally seen at the
Athenaeum. Early in 1890 he had a slight paralytic
seizure, from which he never entirely recovered. In his
well-known library, when able to be out of bed, he would
sometimes sit for hours looking out wistfully at the view
over the park, and on the morning of December 16, 1892,
the end quite peacefully came.

As to Owen's position as a writer on anatomical
science, we have no occasion to enter, for what we con-
ceive to be by far the most interesting portion of these
two volumes is a criticism, in the true sense of this word,
thereof so straightforward, searching, and honest as to
leave nothing further to be desired. We should like to
have transferred the greater part of this analysis by Prof.
Huxley of the work done by Owen to our pages. He
doubts " if in the long annals of anatomy more is to be
placed to the credit of any single worker " than to Owen,
and his is " work some of which occupies a unique
position, if one considers, not merely its general high
standard of excellence, but the way in which so many of
the memoirs have opened up new regions of investiga-
tion."

As to the Judgment passed on the speculative side of
Owen's work, will not all now deplore that so much
tireless industry, great capacity, and extensive learn-
ing were spent on themes profiting so little as the arche-
type of the vertebrate skeleton and the nature of limbs .'
Perhaps it may seem to some that Prof Huxley has
NO. 13 I 2, VOL. 51}

T"!

devoted too much space to Owen's speculative writings,
but, as he says :

" Obvious as are the merits of Owen's anatomical and
palgeontological work to every expert, it is necessary to
be an expert to discern them ; and endless pages of
analysis of his memoirs would not have made the general
reader any wiser than he was at first. On the other hand,
the nature of the broad problems of the ' Archetype '
and of ' Parthenogenesis ' may easily be stated in such a
way as to be generally intelligible ; while from Goethe to
Zola, poets and novelists have made them interesting to
the public. I have therefore permitted myself to dwell
upon these topics at some length ; but the reader must
bear in mind that whatever view is taken of Sir Richard
Owen's speculations on these subjects, his claims to a
high place among those who have made great and per-
manently valuable contributions to knowledge remain
unassailable."

Several interesting portraits of Owen, taken at different
periods of his life, form part of the illustrations of these
volumes. There are also sketches of the Gateway,
Lancaster Castle, and of Sheen Lodge, in Richmond
Park.

ELECTROMAGNETIC THEORY.
Electromagnetic Theory. By Oliver Heaviside, F.R.S.

Vol. I. (London : The Electrician Printing and

Publishing Company, Limited, 1893.)

E basis of Mr. Heaviside's treatise is the inter-
inked magnetic and electric circuits. This is
taken from Maxwell, but it is much more fully developed,
and the analogy between the electric and magnetic cir-
cuits is followed out with great care, and is insisted upon
at every turn. That you can have a conductor charged
electrically, while you cannot have a single magnetic pole,
destroys the perfection of the analogy but little. There
is a more serious hiatus in the absence of the magnetic
analogue to an electric conductor. Mr. Heaviside, how-
ever, completes the analogy by imagining such things as
magnetic conductors and magnetic currents. The mag-
netic displacement and convection currents of course
exist, but magnetic conduction current, with its corre-
sponding magnetic conductivity, is a most useful notion.
The ideas of the magnetic current must not be confused
with the unscientific notions of magnetomotive force
and magnetic resistance, which are supposed to bring
electromagnetisin within the intellectual reach of the
benighted practical man. At first Mr. Heaviside uses
the hypothetical magnetic current as a means of giving
his readers a thorough grasp of the interlinked circuits,
and of completing the analogy between them. Later,
however, in dealing with submarine messages, he shows
that magnetic conductivity outside the wires, w^hich is
easy to treat mathematically, would have the same effect
on the messages as electric resistance in the cable itself,
which would be more difficult.

.\s Mr. Heaviside's first volume has been already
reviewed in the Electrician and Philosophical Magazine
by Profs. Fitzgerald and .Minchin, and as the work is so
full and so suggestive that a review might be longer than
the book, this notice will deal mainly with matters not
already fully discussed, though of course there will be
some overlapping.

NATURE

[December 20, 1894.

It is almost needless to say that Mr. Heaviside does
not believe in action at a distance, that he regards energy
as baing continuous in space, and as moving as matter,
and that he treats ether as an entity, and not as a work-
ing hypothesis. By the way, in discussing ether, as to
whether it is stationary or not, stationary is generally
taken to mean relatively to the earth which is honoured
with our existence, or at least with regard to the sun
which is to give us light. But if motion is considered
with reference to infinite distances, the chances are that
the ether moves pjst us at a speed in comparison with
which '' is infinitesimal. Mr. Heaviside hopes that in
the future the young will be trained up to believe in ether
as a thing, and will therefore believe in it ; but this would
be a sort of religion rather than knowledge. No one
doubts that electrical disturbances are propagated at a
finite speed, and matter, with its inconvenient properties
removed or altered, provides a convenient working hypo-
thesis ; but to talk of the inconceivable as existing, is
using words to which no concepts belong. As most
people agree with Mr. Heaviside on these matters, how-
ever, it may be as well to say no more in a review.
Dealing with the medium, or rather its states, Mr.
Heaviside gets rid of the potential treatment. To him
induction and its change is of primary importance, and
potential is a mere derivative of it. The idea of induc-
tion as the essential and potential as derived is less
common with the academical than the practical elec-
trician, who also uses the notion of lines of induction.

This treatise is remarkable, among other things, in
beginning almost at once with the propagation of dis-
turbances at the speed of light. The author hopes that
text-books on light will soon discuss electricity at the
beginning instead of at the end. He certainly
sets a good example by beginning a book on electro-
magnetism with the propagation of disturbances in time.
By the way, he regards chemistry as an ur.mathematical
science ; it is to be hoped chemistry books will soon
begin with thermodynamics and electricity, so as to lay
an engineering foundation for the study of chemical
action.

Mr. Heaviside is, as is well known, a determined
opponent of the use of quaternions in physics, and an
equally strong advocate of the use of vectors; and a
long chapter is devoted to the " Elements of Vectorial
Analysis,' taking more than a third of the book. In
quaternions, vector products have a part at right angles
to both the vectors; theideasthusfittedelectromagnetism,
and Maxwell availed himself of the conveniences of
quaternion notation, and, to some extent, of quaternion
ideas. The relations between vectors in quaternions are
purely conventional, while in electricity they are physical
in one sense, though in another they may be due to
conventionalities of definition. The idea of the direction
of a current llowing along in a wire was derived from the
flow of water in a pipe, and it is possible that we might
have so defined electrical and magnetic quantities, and so
thought of them, that nothing corresponding to vector
products or quotients came in when passing from one to
the other of the electric and magnetic systems. Mr.
Heaviside objects altogether to quaternions in physics,
but does not differentiate clearly between vector and
NO. 131 2, VOL. 51]

quaternion analysis, and professes that he does not or
cannot understand quaternions. It is not likely he can-
not. Perhaps he won't. One difficulty, in the way of
students at least, is due to writers on quaternions defin-
ing something that is not adding as addition, and some-
thing that is not multiplying as multiplication, and to
their removing the operand and treating the operator as
a quantity. This leads to S::^ being negative, to the
square of a vector being negative, and to the reciprocal
of a vector being taken in the opposite direction. When
an eminent scientific writer recently found, by dividing
the value of dy dx byj' that d dx was equal to 62S, some
wrongly thought he did not understand the principles of
the calculus ; but he was only doing in figures what is done
in letters in many branches of mathematics. Mr. Heavi-
side starts off with a definition of the " product " of two
vectors. The scalar part is positive, and the vector part
is as in quaternions, but there is no idea of the multiplier
rotating the multiplicand, though he gives no reason wh\-
the multiplicand need not be looked upon as turned
through a right angle. It may be asked how Mr. Heaviside
avoids quaternions. Using the word in one of its
many senses as the operator necessary to change a vector
into another, he avoids the difficulty, for the present,
by not dividing. Surely if vectors are to be multiplied
they must also be divided. If we have the induction
and current at an angle, we can find the force ; is it not
as reasonable to find the induction or current if the force
and one of them is given ? Perhaps Mr. Heaviside may
devise a new quotient or operator which will do this. If
ai3 = y we might expect that y'ii = a. This is not so in
quaternions, because the scalar part of aji is lost, and
the quaternion 7,^ gives no scalar part. To recover <i
there might be a term Safiji. Perhaps Mr.
Heaviside will give his own ideas about division in his
next volume. Meanwhile, though he avoids the ideas
of turning, every vector multiplier is just as much a
quaternion as any in Hamilton or Tait.as far as the versor
is concerned. A quaternion, though sometimes called
an operator, is really two operators. Mr. Heaviside
admits quaternions can be developed from his defi-
nitions. He also finds it difticult to think of energy dis-
appearing in one place and appearing elsewhere without
passing through intermediate space ; surely then he can
look upon a vector disappearing and reappearing in a
new direction, and of a new length, as having passed
through intermediate positions and lengths. He then
gets the idea of roots of quaternions, ^/ I~i, and so
on, without complicating vector analysis, and has a
system which will do all his vector algebra well, which
makes sense of imaginaries and exponential values of
sines and cosines, which does not involve the study of
new symbols or ideas, and which is already worked out :
in short, quaternions. He finds difficulty in knowing
when a vector is a vector, and when a quaternion. The
answer is: it is a vector when it is a quantity, and the
versor of a quaternion when it is an operator. There
would be no difficulty if peopledid not confuse an operator
with the ([uantity that specifies it. Confusion, which
is common to Mr. Heaviside's vector algebra, may
come in between the scalar and vector part of the
product of two vectors. He continually falls back

December 20, 1894]

NATURE

173

on cartesians, and his vector work is apt to de-
generate into cartesian shorthand. The object of a
calculus is not to save printing, and it is no advantage to
have an expression condensed into two or three symbols
if you have to think it out at length to understand it.
Shorthand is not necessarily short-thought, especially if
•it also involves writing operators as quantities. It is
possible to know the meaning of

(up - — I H where — i

dt

IS '-'

d

it is also possible to knoiv what is meant by " Boyle was
the father of chemistry, and brother to the Earl of Cork."
It might be suggested that if Mr. Heaviside wants to
make either vector analysis or quaternions simple to
physicists, he should avoid the confusion between opera-
tors and quantities, and between operation generally
and multiplication in particular ; or else write an intro-
ductory calculus of functions showing where such liber-
ties can be taken with impunity.

Mr. Heaviside has a rooted aversion to 477. This factor
came into the system of units from statics, as the mathe-
matical treatment of electricity was much the same.
Mr. Heaviside employs a medium treatment, and thinks
that 47r should, therefore, disappear. He thinks that
Maxwell and other mathematicians did not know how
4Tr came about, and thought it was a physical necessity.
With his treatment it is an advantage to remove
the 477 from its usual place ; but it only appears
in the denominator elsewhere. It is like the eruption
due to a disease : suppress it, and it appears elsewhere.
The unsavoury metaphor is not ours. The disease is
-the area of a unit sphere being 477. Until Mr. Heavi-
side can cure that, he cannot really eliminate 47r. He
whitewashes 477 whenever it appears in his book, saying
that it is not the B.A. 477 of amazing irrationality. When
a man refers to his own ideas as alone rational, nr based
on common-sense, or well-known facts, he is generally
wrong.

.Mr. Heaviside is, as is well known, a prolific inventor
of new terms. He says he hates grammar ; he has also
a murderous hatred of the ()ueen's English when invent-
ing terms such as " leakance," " reactance," and " potted."
Generally speaking, a writer has no business to insist
that his reader shall study a new terminology ; but
when any one of Mr. Heavisides reputation invents
names which are euphonious and good, they become
parts of our language, and we must thank him, especially
when his terms are suggestive and systematic. The
example is bad though. The English language is
capable of improvement ; but if every writer is to
alter it to suit his ideas, it will not improve. It is a
matter of taste which terms should be adopted ; many
object to voltage and gaussage as unsystematic where
anipereage, farradage, &c., are not used. Voltage was
originally used to denote the pressure for which lamps,
dynamos, &c., were designed by the maker, whatever
they were run at. Pressure belongs to the same set of
ideas as current, capacity, resistance, and quantity ; and
if they are used, should also be employed. It is, how-
ever, a matter of taste only.

NO. 1312, VOL. 51]

The style is that of Whitman, except that Mr. Heaviside
is not affected, and has something to say. The similarity
is also noted in the Philosophical Magazine. Every line
of the book is important, and it is full of interesting
digressions on all sorts of subjects. Though the con-
verse may not be true, all clever men have a sense of
humour, and it is therefore a pity that scientific writers
emulate the ponderous dryness of the theologian. Mr.
Heaviside's work bristles with humour of a type which
he has invented.

It is generally assumed that a review should be written

by a man who could have written the book himself. In

the case of a writer of Mr. Heaviside's calibre there is

difficulty in getting such reviewers. The real object of a

book is, however, to teach not those who know the

contents already, but the student, and it may therefore

be an advantage to review a book from the student's

point of view. This review must, therefore, be taken as

from that point of view ; that is, as written by a reader

who has not devoted a large enough portion of his time

to the study of mathematics or mathematical physics to

be more than a student of them.

J. Swinburne.

RECENT PSYCHOLOGY.

Lectures on Human and Animal Psychology. By Wil-

helm Wundt. Translated by J. E. Creighton and E.

B. Titchener. Pp. x. 454. (London : Swan Sonnen-

schein and Co., 1894.)
Grundriss der Psychologic. \'on Oswald KUlpe. Pp. viii.

478. (Leipzig: W. Engelmann, 1893)
Introduction to Comparative Psychology. By C. Lloyd

Morgan. Pp. xiv. 382. (London : Walter Scott,

1894)
Psychology for Teachers. By C. Lloyd Morgan. Pp. x.

251. (London: Edward Arnold, 1S94.)
Primer of Psychology. By George Trumbull Ladd.

Pp. XV. 224. (London : Longmans, Green, and Co.,

1S94.)

THE translation of Prof. Wundt's well-known lectures
is taken from the second revised German edition
which appeared in 1S92, and is therefore well up to date.
It is the first work of the author to appear in English,
and the choice made by the translators is a good one :
while the book will give to those specially interested in
psychology a general sketch of the author's views. Its
popular and lucid form will appeal to a wider circle of
readers who would hardly care to digest the details and
technicalities of the " Grundzuge der physiologischen
Psychologic."

The greater part of the book is devoted to human
Psychology, especially in its physidlogical and experi-
mental aspects, and there are several interesting chapters
on animal psychology, and a short account of the author's
views on hypnotic conditions. Prof. Wundt's own
opinions are staled rather more dogmatically than is
altogether suitable for an elementary book in a science
like psychology ; thus, in dealing with intensity of sensa-
tion, the validity of the logarithmic formula is very posi-
tively enunciated, and it is somewhat surprising to find

174

NA TURE

[December 20, 1894

on p. 306, that indirect association of ideas is " easily
demonstrated," when several investigators, one recently
in Prof. Wundt's own laborator)-, have failed to find any
evidence of such a mode of association.

The translation has been verv well done, and especial
care has evidently been devoted to the rendering of the
German psychological terms. The translators have very
freely used the term " to sense " as a verb corresponding
to sensation, and as the equivalent of " empfinden."
This American innovation, which has already been advo-
cated by Dr. Titchener, is also used by Prof. Lloyd
Morgan in his two books, and it must be acknowledged
that there is decided need of some such term.

Dr. Kiilpe is chief assistant to Prof. Wundt at the
Leipzig Institute, and his experience in teaching and in
directing investigation must have contributed largely to
make his book what it is— one of the best existing ex-
positions of experimental psychology. The general
teaching follows that of Wundt, but there is much that
is novel in matter and arrangement. Physiological
details and the technique of experimental methods are
omitted or treated very briefly, but the principles of the
methods are fully discussed. Dr. KUlpe's book will
probably be largely used as a te.\t-book for advanced
students.

Prof. Lloyd Morgan's two books, to a certain extent,
cover the same ground. Each is an exposition of general
psychological principles to serve as guides, in the one case,
to the scientific study of the animal mind ; in the other,
to the practical study of the child's mind. Both books
are characterised by the sound common sense with which
the author treats his problems.

The views held on the nature of the animal mind are
very similar to those of Wundt. Both agree that in
studying animal psychology the scientific method is to
explain actions by the simplest possible mental processes,
and this method has led both to similar conclusions,
although expressed in sotnewhat different language.
Wundt refers all intelligent acts of animals to simple
associations, to the exclusion of any higher apperceptive
process ; while Prof. Morgan explains such acts by simple
sense experience, and doubts, though he does not deny,
the existence of any true reasoning or reflective process.
A point justly insisted on by Prof. Morgan is that obser-
vation of an apparently rational action in an animal is of
little value without knowledge of the process by which
the action has been developed ; " in zoological psychology
we have got beyond the anecdotal stage ; we have reached
the stage of experimental investigation."

The book for teachers is very interesting, and contains
much that should be of practical value. It is noteworthy
that the appreciative preface, with its ample recognition
of the part that a knowledge of psychology should take
in the equipment of the teacher, is written by Dr.
Fitch, late one of H.M. Chief Inspectors of Training
Colleges.

Prof. Ladd has attempted a very difficult task in
writing a primer of psychology suited for the young.
His book is often simple and clear ; it is to be feared,
however, that youthful readers will find much of it
beyond their capacity. The author has, at any rate,
avoided the fault of being too dogmatic.

NO. 1.^12, VOL. 5 1]

OUR BOOK SHELF.

Radiant Suns. By Agnes Giberne. (London : Seeley
and Co., 1S95.)

In this sequel to a former work, the reader is taken
by easy stages into the domain of spectroscopic astro-
nomy and the evolution of worlds. Though follow-
ing some astronomers who ought to know better, the
authoress takes the unphilosophical view that the whole
process of stellar evolution is one of cooling ; and this is
the more difficult to understand, as she is evidently not

^ unfamiliar with the fact that a condensing bod v may

, actually be getting hotter (p. 307). While strongly'advo-
cating the value of hypotheses as aids to investigation,
she is inconsistent enough to make contemptuous
reference to the " half-tledged " theories of "scientists
of a lower order" (p. 240) ; her qualifications for making
such distinctions are not very clear to us, but ht-r opinions
seem to depend to some extent on personal bias, since
special prominence is given to the views and work of
one observer.

A preface is contributed by Mrs. Huggins, who is
careful to disclaim responsibility in matters of opinion,
and laments that the masses of men overlook the fact
that " the mvestigator, absorbed in pursuits far removed
from those of ordmary life, is also a toiling worker, and
a worker of the highest order."

[ The illustrations are admirable and quite up to date.
It would be worth while, however, to revise the coloured

' plate of stellar spectra, so that the spectrum of Vega
would not be robbed of its strongest characteristic — the
lines of hydrogen.
We believe that the book will succeed in awakening a

j desire for further knowledge in the minds of thoughtful
readers ; and if so, it will serve a useful purpose.

Album von Papi'ia-Typcii. \'on A. B. Meyer and
R. Parkinson. (Dresden: Stengel und Markert,

1894.)

To ethnologists, the Papuan race is one of the most
interesting in the world. Whether the Papuan represents
a distinct type of mankind or not is doubted by some
observers, though the balance of evidence is in favour
of that conclusion. This splendid collection of fifty-
four plates reproduced from photographs, and repre-
senting about six hundred portraits of individuals,
should be of great assistance in studying the similarities
and differences between the typical Papuan, and the
natives of southern and eastern New Guinea. The
photographs illustrate the natives of New Britain, the
Duke of York Islands, New Ireland, Admiralty Islands,
Solomon Islands, German New Guinea, and Dutch New
Guinea. They represent the pcuple as they are ordi-
narily seen, and also decorated with the strange costumes
assumed at feasts. Particul.trly striking are the pictures
of natives of New Britain adorned for one of their
Dukduk dances, and of the ingenious basket-work
traps used by the fishermen. ICthnology will benefit
by the publication of this collection of really excellent
pictures.

Farm Vermin, Ihlpful and Harmful. By various
Writers. Edited by John Watson, K.L.S. Pp. 85.
(London : William Rider and Son, Limited, 1894.)
Composite books are almost always unsatisfictory, the
chapters by the various contributors lieing necessarily
unequal in quality and kngih. We really cannot
understand why this little book of eighty pages should
not have been written by a single zoologist, instead
of the eight who have helped to consliuct it. The
only justification for the patch-wcirk is that each of
the writers is more or less an authority upon the subject
he describes ; but the book is of such an elementary

December 20, 1894]

NATURE

175

character, that it is difficult to believe that so many
minds are necessary for its construction. The contribu-
tors are Sir Herbert Maxwell, Mr. O. V. Alpin, Mr.
John Cordeaux, Mr. Cecil Warburton, Dr. J. Nisbet,
and Mr. C. 15. Whitehead. Each tells his tale in his
own way, and the editor amplifies the information here
and there by means of foot-notes. Farmers will find
the book a handy and simple guide, and one which will
enable them to know their friends and enemies among
the " varmints."

LETTERS TO THE EDITOR.

[The Eililor doet not hold himself responsible for opinions ex-
pressed ty his correspondents. Neither can he undertake
to return, or to correspond with the writers of, rejected
manuscripts intended for this or any other part of Nature.
No notice is taken of anonymous communications.^

The New Cypress of Nyasaland.

The interesiing accnunt of Widdringtonia whytei (Nature,
Nova ' t)cr 22, pp. 85-87) discovered by Mr. Whyle on the
Milanji plale lU, suygrsls a few brief comments.

(1) Ii is said lo extend "the geographical range of the
genus hi'herlo known only from South Africa, Madagascar,
and Mauritius into tropical Africa." As far as the latter state-
ment is concerned, this is no doubt true. But the existence of
any spi^cics of the genus in Madagascar or Mauritius seems to
be wanting in sufficient evidence, though repeatedly cited by
authorities. Thus Madagascar is given in the geographical distri-
bution for the aggregate genus Callitris in Hem ham and Hooker,
"Genera flunlarum," vol. iii. p. 424; Dr. Masters, jfourn.
Linn Soc. Bot vol. xxx p. 17, says "one (IViddringtonia) has
been di-cuvcrt-d in Madagascar"; Mr. Rendle, Trans. Linn.
Soc. (2nii series) Hot. vol. iv. p. 61, speaks of the " South
African and Mascarene IViddringtonia."

All these statements aie based on a species, IViddringtonia
Commersonii, which was cultivated at Rtiduit, Mauritius, and
of whiv:h the native country was assumed to be Madagascar,
though this has never been confirmed.

In 1S06, it is referred to in the " Nouveau Duhamel," vol.
iii. p. 10, as Thuya quiulrangularis, with the following remark:
"Habile I'tsle dc Madagascar; depui> quelques annees on le
■cultive au rc'tuit, jardin de botanique a I'lsle de France."

The Madagascar habitat was apparently purely conjectural.
And though the island has of late years been pretty assiduously
worked by French, German, and English botanical collectors,
no contfi-r ha> been delected in it except Podocarpus.

In l8j3 the ■ evelopment of the myth went a step further.
Brongiii.in cites the species in the Ann. des Sc. Nat., series I,
vol. xxx. y. 19a, under the name of Pachylepis Commersonii,
with the lemark : " llab. in Insula Mauritii in loco dicto Le
Rcduil (Commerson, 1 769)."

Thus ii will be seen that, starling as an introduced Mada-
gascar spe'ies cultivated in a botanic garden in Mauritius, it
finishes wnh beipgtreaied as an undoubted nauve of that island.

It i^, however, to be noted that from "Biker's Flora of
Mauri tus and the Se>chelles" (1877) the Coniferce appearto be
entireb ab-ent from 'lie Mascarene Islands.

(2) 1 hete is iio'.hing improbable in a IViddringtonia oc-
curring in Mailaga'Car. But none has yet been detected with
any cett.iinty. It seems not improbable that Commerson's
plant was really derived from S uth Africa. This would seem
to be the conclusion at which Carricre arrived in 1867,
"Contieres." ed. ii. p. 67: — " Cette prciendue espcce me
parail c le a peine une forme de la precc'dente." ( /('.
ctiprcssoides, one f the two South African species).

(3) Ti e Conifer, c lor the most part can hardly be regardeil as
other than a veiy ancient and a decaying group. Their existing
distribution is therefore peculiarly interesiing. Bentham and
Hooker unite under Callitris a number of small genera which
practically only difTc in he number of their ovule-hearing scales
andin ihcir ncMgrajihic 1 distribution. They divide the genus so
reconstituted inio four sections, of which two are broadly
Australian, iwo are African. Other instances of parallelism
between ihe .\u-.lralian and .\fiicin floras are well known and
are full ot inietest. Of the .\frican sections one is confined to
the norih, wnh one species, Callitris quadrivalvis , which yields
the gum Sandarach of modern ommerce, and produced the

NO. 1312, VOL 51]

Thyine wood once so prized by the Romans ; the other
section, with two species, is confined to the south. The oc-
currence of a third species on the Milanji highlands is entirely
in harmony with whal we know of the distriimtion of plants in
Tropical Africa. As has been shown now in numerous cases, a
temperate and possibly more ancient flora more or less overlies
at elevations where it can exist, the lower lying tropical one,
and it forms a series of broken links by which the connection
of the temperate flora of Europe and of the Meiiiterranean basin
with that of South Africa, and even of the Madagascar uplands,
are at least indicated.

It may be remarked that another coniferous genus, Podocarpus,
behaves much in the same same way as Callitris. Four of the
five African species occur at the Cape, and two on Kilima-n'jaro.
funiperus, on the other hand, though well represented in
Northern Africa, occurs in Abyssinia and the Msisai country,
but yet does not reach South Africa.

W. T. Thiselton-Dyer.

Royal Gardens, Kew, December 10.

The Kinetic Theory of Gases.

I SHOULD like to ask Mr. Culverwell what are the "other
considerations " from which we know that in a system of elastic
spheres the error law gives the only permanent slate.

I will endeavour to extend the proof of the Htheorem which
I gave for elastic spheres to a more general, but not the most
general, case,

The coordinates of a molecule are x,y, z, defining its position
in space, and '/,... qn-^^ the momenta are /, . . . A. ; and
different values ol the same variables shall be denoted by PQ
and, as the case may require, by accented letters ;5'P', &c. The
number per unit volume of molecules, for which the variables/
and tj are between assigned limits, \^ fdq dp, andy is a function
of the/'s and i/'s independent of .xyz.

The number of pairs for which one molecule has variables
P'O' between assigned limits, i.e. is in the state P'Q', and the
other /'(/' between assigned limits, i.e. is in the stale p'q', is
YfaV'dfYdp'dq'.

Each molecule has a centre of gravity. It is possible to
describe a sphere about that point as centre, such that if the
centre of gravity of another molecule be on or beyond that
sphere, no appreciable force is exerted between the two
molecules. Let a • e the least radius of such a sphere. Then
when the centre of one molecule is on the sphere of radius a
described round the centre of another, an encounter begins or
ends between the two molecules.

Now suppose an encounter to take phce between a pair of
molecules one of which is in the state P'Q', and the other in the
state /'.y'. As the result of the encounter the variables P'. . . q'
assume new values, but what particular values they shall
assume, given P''J'/''/ before encounter, depends on the two
coordinates ffip' defining the position of the centre of one of the
two molecules on the " a" sphere describe! about the centre of
the other at the commencement of the encounter.

Inasmuch as no work is done in moving the centre of one
molecule on the surface of this sphere, it is evident that the
"sorting demons" can make the result of the encounter
anything that they please, conservatis conservandis.

Let us suopose thit if these spherical coordinates lie between
the limits 6' and 8' -t- d6', <p' and </>' -f d<p', the variables will
after encounter lie between the limits P . . . P -f i/H, &c., that
is, the pair will be in the slate Vq, and B'(p' will have become
0 . . . e i- de and (j> . . . (p + d<l>.

I will now assume (condition A) that the coordinates 6'(p' are
taken at haphazard without regard ti the variahles \"q' ; if that
be so, the chance that, for given P'q' before encounter, the pair
of molecules shall be in the Vqe(p state afler encounter is
de'd<ti'

4ir

But the number of pairs which now are in the state P'q' is

F'/WP' . . dq'
And therefore the number which after encounter will be in the
state PqSip, having passed thereto from the state P'q', will be

r/'dP'dQ'dp'dq'!'^'''^'

which is equal to

4»

47r

' dPdQdpdqdedii.F'f.

176

NA TURE

[December 20, 1894

Now let P' . . . ^' be made to pass through all values from
which, 9' and ^' being suitably chosen, they can assume after
encounter the given values V . . . V + a? . . . ii . ■ . q -h tfq.
The final values of 6 and ^ will varj', but all possible
values of 9 and <p must appear for some or other of the
values through which P' . . . if pass, and therefore we shall by
ihis process obtain the whole number of pairs which are in the
state V . . . q after encounter, without restriction of the state
which they had before encounter. It will be, namely :

d^(Kidpdq

//'S'/'d?-dQ;dp'dq'

ff dVdCj'dp'dq'

But the number which are in the state P . . . y now is

dfdCldpdqYf.

Therefore, as the result of encounter,, it is increased by an
amount proportional to

d?dqdpdq f [{¥■/■ -F/)dP'dq'dp-dq:

From this point, thanks to the labours of Boltzmann and
Watson, the proof is easy, and I need not repeat it, that

JIT

— is negative or zero.
dt ^

I have assumed condition A. I do not say that that is the
only assumption that will answer the purpose. But it is suffi-
cient. And it is, I think, the most useful assumption, because
the distribution of coordinates assumed to exist is that which
would tend to be produced by any disturbances acting on the
system (rom without.

The proof in this form is not open to the obiection that by
reversing the velocities we can prove two mutually contra-
dictory propositions.

Oh, that now my friend would write a book, and point out
with regard to these assumptions what more is necessary, or
what le.-s sufficient. S. H. Burbury.

Lincoln's Inn, December 5.

P. S. — Dr. I.armor describes the reverse motions as the
" exceptions which do not disprove the rule." I would apply
the maxim Exccptio probat re^itlam in a slightly different sense.
They are the exceptions whicfi put the rule to the proof. They
compel you to define accurately the limits wiihin which the
rule holds. When that has been done lor Boltzmann's law (if
it has not been di>ne already), it will be lime to consider how
far the cases which fall within the law are more important than
those which fall without it. S. H. B.

December 15.

The presence of any assumption in Dr. Watson's able proof
of Bilizniann's Minimum Theorem might easily be overlooked ;
but if Mr. Culverwell will apply his test of reversing the motions
in each sepaiate stage of the proof, he will unearth the assump-
tion at once. On the top of p. 43 Dr. Watson says :

" And therefore the expression

FA/P; . . . r/y„-, -;„

is the number of pairs of molecules, one from each of these sets,
passing from the slate P, P-fr/P... q, q + dq to the slate
F', V + dV' . . . </', q' + dq' per unit of lime, where g„ is put
equal to o my'."

Now let the motion of every molecule be reversed as Mr.
Culverwell suggests. It will be convenient to speak of the two
stales as the iniartenl.J and accented stales, and we shall thus
have the assumption that the expression

F/,/P, . . . dq.,^^ ,/„

(which is also equal lo

F/rfP,' . . . <//„_, '/'„ bul ml to V'f'd?i' . . . dq'„-^ 1),,')

.«hall reprc»enl ihe number of pairs of molecules passing back
from the acctnlcd to Ihe unaccented slate, and this number will
depend on F ami J, the frequencies of distribution v/iic/i the
molecules are about to have after ihc colli ions ha-.'i taken place.

If ihi< a^sumplion be made we doubtless shall have a case
io which II lends to a maximum instead of a minimum, and if
Mr. Culverwell endows his molecules with the power of
forelhouglii and Ihe prediction regarding their future stale
necessary 10 enable them to regulate their movements according
to this suppositious law, then Dr. Watson's proof, and indeed

No, 1312, VOL. 51]

any proof, will necessarily fall to the ground. If however the
motions of ihe molecules are allowed to take their own natural
course, and nothing special is known about them, the only
reasonable assumption to make is that the number of pairs
passing from Ihe accented lo the unaccented state per unit
time is

F7VP/...^/„_,/,.,

and this assumption is actually made by Dr. Watson in the
next few lines of his proof th.it H lends to a minimum.

What Mr. Culvervvell's objection shows, then, is that it is
possible to conceive the molecules of a gas so projected that
they would not tend lo assume the Bollzmann-Maxwell
distribution.

But practically it wouH be impossible to project the
molecules in their reversed motions with sutiicient accuracy to
enable ihem lo retrace their steps for more than a very few
collisions, just as, if we try placing a number of pool balls in a
straight line on a billiard table at distances of a foot or two
apart, we find it impossible to project the first ball with
sulTicient accuracy fur each liall to strike the next in front all
down the line if there are many balls.

The question of the choice of coordinates has been so fully
dealt wilh by Dr. Watson that I need say nothing more.
However, if Mr. Culverwell prefers, he may tiansform from
Dr. Watson's Qj . . . q,, 10 any other vaiiables defining the
position of ihe/afrof molecules, prozided that he -works wilh
the corresponding generalised momenta instead ol Pj , . . /„,
and he will have no difiiculty in choosing one of his new
variables to be such that it vanishes at an encounter.

I think Loreniz's paper (" Sitzungsherichte der Wiener
Akademie," 18S7, p. 115) affords the fullest account of the
assump'icins underlying the proof of the Minimum Theorem.

Cambridge, December 5. G. 11. Brya.n.

Science and History.

I SEE by your review of the National in the last number of
NATt;RE, p. 162, that Pr.if. G. W. Prolhero, in his "Address
on History," takes occasion to notice Buckle's " History of
Civilisation." " Buckle," he says, " in illustrating his theory
that national character depends largely upon food, attributes
the weakness of the Hindoos to an alnmst exclusive diet of rice.
A striking bul misleading generalisation, for, as Sir H. Maine
has pointed out, the great majority of Hintoos never eat rice at
all" Buckle, ho*cvrr, never said anything of the kind; and
since no author wrote more clearly than he did, it is evident
that the Professor, like many before him, has not taken Ihis
extr.ict at first hand.

What Buckle did say was : that rice, millet, or whatever the
Hindoos fed on, was grown with little trouble and in abund-
ance ; that the climate made clothes superfluous; that living
was consequently cheap, and that hence the population increased
beyond the demand for labour ; labour was ill-rewarded, and
the population became practically enslaved. I put the aigu-
ment very shortly and inadt:<|uately, for anyone may see it fully
sel forth in the "History of Civilisation,'" 185S, vol. i. p|i.

63-74-

Sir II. Maine utterly failed lo perceive that whatever might
have been the fool that the Hindoos lived upon, it m.ade no
difference to the argument provided that that food was cheap.
He was further wrong in his slalemcnl that the Hindoos did not
feed on rice, as it used to be a far more usual article of diet
than in later limes ; bul his worst mistake was to limit the
argument to the people of India, who were only one people, out
ol many, used lo illustrate ihe iioint.

Alfred IL Hum.

London, December 18.

Geometry in Schools.

Asa mathematical teacher of long experience, I wish lo stale
that I thoroughly agree with Prof Hcnrici that experimental
geometry should lie taught antecedently to and concurrently
with a rigorous deductive course.

Teachers who have lo introduce young students to ihc siudy
of deductive geometry (lo begin Euclid, as it is called) are
conlronicd with iwo difficulties. Their pupils in many cases (l)
have never been seriously taught lo reason about anyll ing ;
(2) have no slock of geometrical ideas to rea-on aljout. The
attempts made in kindergartens to give sound notions of form

December :o, i Sqj

NA TURE

177

by means of models, patterns, &c., are excellent a^ far as they
go, but there seems lo be great need of a systematic course
specially designed to lead gradually up to the siudyif deductive
geometry. The following books will be fcund useful by
teachers who care to give the experimental method a trial :
"Paper Folding," by T. Sundara Kow (Addison and Co.,
Madras) ; " Tnventional Geometry," by W. G. Spei cer (Wil-
liams and Norgaie); "Experimental Geometry," by Paul liert
(Cassell and Co.) ; " Natural Geometry," by A. Mault (Mac-
niillanand Co.); "Geometrical Drawing," by A. J. Pressland
(Rivinglon, Percival, and Co.). Tothese may be added some
older ones, which n ay occa^'onally be picked up second-hand :
Scott Russell's "Geometry in Modern Life," Dupin's " Ma-
tbemaiics," and " Conversations on Geonetry " (Anon.).
Adelaide Square, Bedford. Edwakd M. Langlev.

LIUENTHAL'S EXPERIMENTS IN FLYING.

IN a previous article in Nature (vol. xlix. p. 157) we
had occasion to refer to the very interesting experi-
ments which were being carried out by Herr Otto
Lilienthal with regard to the possibility of human beings
being able to acquire the art of flying through the air,
more or less, in the fashion of birds.

These investigations in aerial navigation are con-
spicuous from all other attempts of the present day, by
their great difference in the method of procedure adoptee).
The principle of Maxitii's machine, for instance, is to
construct an apparatus to navigate the air by itself,
carrying one or more passengers. Every movement
of the machine, however, is left to the apparatus itself,
and to battle with the difficulty of sustaining its own
equilibrium the mechanism must necessarily be most
complicated.

Lilienthal depends for the success of his apparatus on
himself, trusting lo his powers of instinct to keep his
equilibrium by corresponding movements of his centre of
gravity. Man in this case is the main llyer,the apparatus
being only an adjunct, and it is from the ability of the
former that he expects to obtain positive results. His
apparatus is siinple, cheap, and easily constructed ; these
are great points, as experiments can be carried on, even
at the expense of the loss of a few machines.

The whole success of aerial tlying can be summed up
in the word c'(/iii/ibriii»!, and it is here that the diffi-
culty lies. Given a perfectly quiet or very nearly still air,
there is no doubt that machines can be constructed so
as to soar and travel through the air. This stale of at-
mosphere is \ery rare ; but, on the other hand, there are
all sorts of disturbances, currents, and wave-motions
which render aerial navigation a far greater difficulty
than is usually imagined.

One often envies a bird which, with perfect case, soars
above us ; but it must be recollected that it is endowed
with a delicate system of nerves which are always on the
alert, and answer to any call made on them to sustain
equilibrium. These movements are made quite uncon-
sciously, and with the loss of the minimum amount of
energy. To construct an apparatus that would accom-
plish this in an etiicient manner would be simply impos-
bible ; but there seems no reason why man should not
approximate to it to a certain extent by the help of an
appropriate framework. With perseverance and many
trials he should be able to master at least some of the
rudiments, and eventually make short llights.

For this leason Herr Lilienthal's experiments must be
looked upon as yet only as first attempts, and con-
sequently as experiments pure and simple, and expe-
rience only will show how far they can be successfully
brought. Falls must be expected in the preliminary
trials until the operator becomes accustomed 10 the many
new conditions which make themselves apparent at
every step, before they can be mastered instinctively.
Similar ditiiculties have to be contended with when learn-

ing to ride a bicycle. The beginner is at first unable to
keep his equilibrium, and so wobbles here and there,
with the loss of much power, until he eventually finds
himself hugging the earth. This is simply because he
is doing something unusual, and is not accustomed to
the new conditions. An adept rider, on the other hand,
never thinks of the possibility of falling, and quite un-
consciously keeps his equilibrium without any exertion or

loss of power on his part. So it is with this new sailing
machine, and it is only by practice that success can be
attained.

To commence operations the simplest apparatus must
be used, and the easiest steps attempted. This is the
way Herr Lilienthal began. In his first experiments,
with the help of his wing-shaped framework, he made
flights from elevated points in calm weather, the lengths

NO. 13 12, VOL. 51]

Fig. a.

of these flights increasing as he gained in experience.
Sometimes as many as 500 metres were covered in one
bound under satisfactory conditions.

In his more recent experiments he has been making
considerable progress in developing this mode of sailing.
Two objects have been kept well in mind : the first, to
accomplish that method of- sailing which is adopted by
birds which spend hours in the air at a time without ever

178

NATURE

[December 20. 1894

flapping their wings ; and second, to apply to his
apparatus such dynamical means that will enable
him, when sailing in a calm atmosphere, to prolong his
flights.
To carr\- out these experiments he has thrown up, in

Fig.

the neighbourhood of Berlin, a large conical mound,
fifteen metres in height ; this mound he uses as a
starting-point for his flights. In Fig. i the operator
is shown just commencing one of these flights.

sails off until he alights again on the earth. Fig. 2
shows him just about to alight. It will be noticed that
to come down easily and softly, he puts on the brake by
offering to the air a greater expanse of wing, whereby
his velocity is at once reduced.

Ry experience Herr Lilienthal has found that although
in quiet weather he can manipulate his craft very easily,
in windy weather the operator has to be more careful.
The investigations in this direction have, however, been
satisfactorily made, and he can now by an adroit move-
ment of his body and that of the apparatus sustain his
equilibrium, and sail successfully.

In his article on this subject [Piomcllicus, No. 261,
p. 7), from which these references to his new experi-
ments have been taken, he states that sometimes, when
a strong wind was blowing, he has been surprised by
sudden gusts, which, before he had time to make the
necessary movements to sustain his equilibrium, had
carried him high up in such a manner as to often take
his breath away.

Fig. 3 illustrates the operator receiving such a sudden
shock ; it will be seen at once that to jcontend with
these new conditions he has had to bring his sail up to
the direction of the blast, and to meet it if possible,
while at the saine time he has altered his whole centre
of gravity by a movement of the lower part of his body.

Such movements as these cannot yet be made quite
instantaneously, owing to lack of experience ; but, as he
justly remarks, with more practice he will no doubt be
able to make them instinctively, just as the bicycle-
rider does.

To attain his second object, that is, to employ some
mechanical aid to help him to sustain himself for
longer intervals of time in the air, he has constructed a

m^.

yT'

Fig, 4.

With a tight grip of the framework with his hands,
he runs quickly down the slope until he has attained a
sufficient velocity to raise him and his apparatus off the
ground. When such conditions have been obtained, he

NO. I312, VOL. 51]

new apparatus, somewhat, but not quite, similar to that
up till now used. .\ good idea of this can be obtained
from the accompanying illustration (Fig. 4).

A comparison of this /lying machine with the sailing

December 20, 1894]

NA TURE

179

machine in the previous figures will show that the ex-
tremities of the wings have been differently constructed,
being composed at the ends of a series of feather-like
sails. These latter are connected with a small machine,
near the operator's body, which is driven by compressed
carbonic acid gas ; it is set in motion by a simple
pressure of the finger. Such an addition has of course
increased very considerably the weight and, therefore,
the difficulty of handling the apparatus, and as yet it has
only been used when the conditions were very suitable,
as one serious fall would break up the machine.

Nevertheless the results up to now are very promising,
and in calm weather Herr Lilienthal has been able to
considerably prolong his flights. When, with the
ordinary sailing machine, he would have come naturally
down to the ground, he has found that an occasional
Happing of these wings has helped to sustain him a longer
lime in the air, and to consequently cover greater
distances.

Herr Lilienthal has shown now, that, with the simple
sailing machine, flights can be made without any great
risk. It would be good for the future progress of this
mode of sailing if those interested in it, and who have
the time and money, would take it up and pursue it
further. What is wanted now is experience, and this
can only be obtained by the co-operation of many
workers.

PE TERS-DENZA—RANYARD .

A STRONG. MI CAL science has lost three of its
■'*■ votaries during the present month. Dr. C. F. W.
Peters died on December 2, and Father F. Denza, as
well as Mr. A. C. Ranyard, passed away on Friday last.
Dr. Carl Friedrich Wilhelm Peters, Director of the
Konigsberg Observatory, died on December 2, after a
protracted illness. He was born on April 16, 1S44, at
the Pulkowa Observatory, where his father. Prof. C. A.
F. Peters, held an appointment under the Russian
Government. In 1849 his father was appointed
to the Chair of Astronomy at Kunigsberg, and
in 1S54 he was made Director of the Altona
Observatory, which was afterwards transferred to Kiel.
The son studied astronomy and mathematics at Berlin,
Kiel, .Munchen, and Goitmgen, and was placed on the
staff of the Hamburg and Altona Observatories. Between
1S69 and 1S72 he made some valuable pendulum obser-
vations, chiefly for the Prussian Government. As
Privatdocent at Kiel University he undertook a long
series of chronometer tests for the German Navy, in the
course of which he proved that they are influenced by
changes of humidity as well as by changes of tempera-
ture. In iSSo, upon the death of his father, he edited
the Aslronomisc/ic Nachrichten for a year, after which
he was appointed Extraordinary Professor at Kiel
University. In 1SS3 he undertook the direction of the
Naval Chronoinetric Observatory at Kiel, whence he
proceeded in 1S8S to the directorship at Kunigsberg,
where he terminated a useful and laborious career.

Father F. Denza died at Rome on the 14th inst.
from cerebral hemorrhage. He was well known to
the scientific world by his works in astronomy,
meteorology, and terrestrial magnetism, and at the
time of his death was President of the Italian
Meteorological Society, and Director of the Observatory
at Moncalieri, which he founded in 1859, as well as of
the \atican Observatory, which was established by the
Pope in 1S91. It was owing to the untiring energy of
Father Denza that the ConispoiukiKa Mctcorologica
Jliiliana was established in connection with the .Mpme
Clubs, and that the results of observations at a large
number of stations in the Alps and Apennines have been
regularly published in the organ of the Italian .Meteoro-

NO. 1312, VOL. 51]

logical Society. He was elected an honorary member of
the Royal Meteorological Society in 1870.

In astronomy his chief work relates to the observation
of meteors. For several years he issued instructions to
observers of meteors previous to every important shower,
and he published numerous tables and papers on the ob-
servations carried on under his guidance, both in Comptcs-
rendtis and the Monthly Notices of the Royal Astro-
nomical Society. When the Directorship of the Vatican
Observatory was taken by Father Denza a very
comprehensive programme was drawn up, embracing
investigations in meteorology, terrestrial magnetism,
geodynamics, and astronomy. Observations in each of
these branches of knowledge have increased in number
every year since then, and the fourth volume of the
Pubblica:ioni of the Observatory, received by us on the
same day as the news of Father Denza's death, is even
greater in bulk than any of the previous ones. Father
Denza was chiefly instrumental in making the Vatican
Observatory one of those co-operating in the production
of the photographic star-chart. He devoted his best
energies to the advancement of the scheme, and to the
progress of astronomical photography. The reports to
which reference has been made, contain evidence of his
knowledge of what had been done in other astronomical
observatories, and of his ability to direct and further the
advancement of celestial photography. His services to
astronomy have earned for him an honoured place in our
memory of the sons of science.

Mr. Ranyard was born in 1845. He was educated
at Cambridge L'niversity, and was called to the Bar
in 1871. He was one of the founders of the London
Mathematical Society, of which he was originally joint
secretary with Mr. George De Morgan, Prof. Augustus
De Morgan being president. He became a Fellow of
the Royal Astronomical Society in 1S64. In 1870 he
was assistant secretary of a joint committee of the
Royal Society and the Astronomical Society, which
organised the expedition despatched to Sicily, Spain, and
Oran to observe the total solar eclipse of December 21.
On his return to England he undertook to assist Sir G.
B. Airy in the preparation of the report of the observa-
tions of the total eclipses both of 1870 and i860. Ulti-
mately Sir George Airy transferred the work entirely to
Mr. Ranyard, and in 1S80 the report was published by
the Royal Astronomical Society as vol. xli. of its
".Memoirs." He observed the total eclipse of July 29, 187S,
from Cherry Creek, near Denver, Colorado, and the total
eclipse of Alay, 1S82, from Sohag, in Upper Egypt. In
addition to papers on the corona and matters connected
with physical astronomy, he also published papers on the
" Early History of the Achromatic Telescope," and on
" Photographic Action." In conjunction wiih Lord Craw-
ford and Balcarres, he undertook in 1 87 2 a series of
experiments on photographic irradiation ; and in 1886
he demonstrated by a series of experiments that the
intensity of photographic action varies directly as the
brightness of the object photographed, and directly
as the time of the exposure. The " old and New
Astronomy," designed by Mr. Proctor, was completed
in 1S92 by Mr. Ranyard, who contributed to it some
very important sections on the structure of the stellar
universe.

NOTES.
The newly-discovered gas is to be the subject of a discussion
at a meeting of the Royal Society on January 31, when Lord
Rayleigh and Prof. Ramsay will present their paper. This
will be the first meeting under a resolution of the Council of
the Society passed last session, whereby certain meetings, not
more than four in number, are to be devoted every year, each to
the hearing and consideration of some one imporiant communi-
catioD, or to the discussion of some imporiant topic.

iSo

NATURE

[December 20, 1894

At the request of the Ottoman Government, Dr. G. Agamen-
none, of the Italian Meteorological and Geodynamic Office, will
shortly proceed to Constantinople to found there a seismological
obseri-atory of the first order. Amongst the instruments to be
erected are an .\gamennone seismometrograph and a tromometer
similar to those in use in the principal Italian observatories.
The tromometer will be provided with a photographic recording
apparatus, and is specially adapted for registering the long,
period pulsations from distant earthquake centres.

Directors of Botanic Gardens abroad will be glad to know
that a list of seeds of hardy herbaceous annual and perennial
plants and of hardy trees and shrubs which, for the most part,
have ripened at Kew during the year 1S94, is given in an
appendix, recently issued, to the AVw Bulletin. These seeds
are not sold to the general public, but are available for ex-
change with Colonial, Indian, and Foreign Botanic Gardens, as
well as with regular correspondents of Kew. No application,
except from remote colonial possessions, can be entertained
by the Director of the Royal Gardens at Kew after the end of
March.

The death is announced of Pafnulij Tchebitchef, the eminent
Russian mathematician. He w.-is a Foreign Member of the
Royal Society, and an Associc Etranger of the Paris Academy
of Sciences.

Dr. F. B Hawki.ns died on December 7, at the great age
of ninely-eight. He was elected a Fellow of the Royal Society
sixty years ago, and was one of the oldest members of the
medical profession.

The Laiuet understands that the Premier has consented to
leceivea deputation to advocate (he formation of a University
for London on the lines recommended by the recent Royal
Commission. The meeting will probably take place about the
middle of January.

The Paris correspondent of the Chemist and Druggist re-
ports that the Municipal Council have presented fifteen hundred
francs to the Ecole Normale Superieure, to erect a bust of M.
Pasteur in ihit college. The Council have also voted in favour
of changing the name of the rue d'Ulm to that of "rue
Pasteur."

At the invitation of the associitei scientific clubs of Berlin,
a numerous assembly met on Friday last in order to com-
memorate the great services rendered to science by the late Prof,
von Helmholtt. The Girman Emperor and Empress, and |
many Ministers and members of Parliament, attended the '
ceremony.

Our Cambridge correspondent informs us that the Coutts
Trotter Studentships in Physics at Trinity College have been
awarded for two years to Mr. I. L. Tuckelt, and for one year to
Mr. S. \V. J. Smith, both being scholars of the College.

The Council of the Marine Biological Association has
appointed Mr. E. J. Allen to be director of (he Plymouth
laboratory, in succession to Mr. E. J. Bles, who lately resigned
that position. Mr. Allen is a pupil of Prof F. IC. Schulize, of
Berlin, and has been engaged in researches upon the ctrlomic
and nervous «y«temi of Crustacea, some interesting results of
which were recently noticed in our columns.

.VrranoemenTs have been made to begin the new series of
Scitnte on the first day of the new year, under wholly different
direction and auspices. The New York Nnlion says that (he
paper will hereafter be under the control of a representative
editorial committee, and will undertake to report on the progress

NO. 1312, VOL. 51]

of science for men of science. The managing committee is
constituted as follows : — Mathematics, Prof. Simon Newcomb ;
Mechanics, Prof. R. S. Woodward ; Astronomy, Prof. E. C.
Pickering; Chemistry, Prof. Remsen ; Physiography, Prof W.
M. Davis ; Paheontology, Prof. O. C. Marsh ; Morphology,
Prof. VV. K. Brooks ; Zoology, Dr. C. Hart Merriam ; Botany,
Prof. N. L. Britton ; Hygiene, Dr. J. S. Billings; Physiology,
Dr. H. P. Bowditch ; Ethnology, Dr. J. W. Powell ; Anthro-
pology, Dr. D. G. Brinton ; Psychology, Prof. Catlell.

The Organising Committee of the International Geographical
Congress have issued an invitation circular to members of geo-
g raphical societies, and all who take an interest in any of the
various aspects of geography, to attend the meetings of the
Sixth International Geographical Congress, which will be held
in London from July 26 to .■\ugust 23, 1895. The subjects to
be dealt with at the Congress will be grouped under the follow-
ing heads : — (i) Mathematical Geography ; (2) Physical Geo-
graphy, including Oceanography and Geographical Distribution;
(3) Cartography ; (4) Exploration ; (5) Descriptive Geography ;
(6) Historical Geography ; (7) .\pplied Geography, including
AnthropoGeography ; (S) Education. Intending contributors
of papers should send in their communications (written in
English, French, German, or Italian) before the end of next
April. -Vn exhibition of instruments, maps, globes, photo-
graphs, and other objects representative of the present state
and past history of geographical science, will be held in connec-
tion with the Congress.

Dr. E. deTeli.enberg writes to us, from the Natural History
Museum at Berne, with reference to a communication made by
Sir John Lubbock to the Geological Society, on November 7
(Nati/re, vol. li. p. 94), on some nummulites from the valley
of Lauterbrunnen at Murren. Sir John Lubbock remarked
that " the find will necessitate a substantial correction of the
geological map" ; but Dr. de Tellenherg says that the nam-
mulitic layer described was known long ago, and is shown on
several geological maps ; while the conclusion, that the rock is
"not Malm, but Eocene,'' appears to have been arrived at fifty
years ago.

In a presidential address to the members of the Tyneside
Naturalists' Field Club, just received. Prof. G. S. Brady gives
an interesting sketch of the present state of fisheries and fish-
culture in Great Britain. He describes a visit to Mr. Armistead's
successful salmon and trout hatchery near New -Vbbey, and
recommends the foundation of a hatchery on the Northumber-
land coast to aid in keeping up and improving the supply of
sea-fish, and of a biological laboratory attached to it for the
scientific study of the marine fauna of the neighbourhood. We
hope that everyone interested in the maintenance of our sea-
fisheries, and in the study ol marine biology in the northeast of
England, will cordially .assist n the realisation of this timely
proposal. A work of this kind, as Prof. Brady suggests, comes
fairly within the powers of the County Councils, which have
alrcaily shown a cammendablc care for the interests of .agri-
culture, and a desire generally to help forward technical and
scientific education.

Thk current number of the />o!liilino meiisiiale of the Italian
Meteorological Society contains a summary, by Profs. K. Bartoli
and E. .Sirocciatl, of their determinations of the absorption of
solar radiation by fog and by cirrus clouds. The investigations
were very carefully conducted, and the results arc therefore of
considerable interest. It was found ih.at a veil of cirrus was
able to intercept as much as 30 per cent, of the sun's rays ;
while a slight fog, equally diffused in all directions, intercepted
from 58 to 92 per cent, of the solar rays, which would have
been transmitted with a perfectly clear sky. Full particulars of

December 20, 1894]

NATURE

181

the numerous experiments made by ihe authors since the year
1885 will be found in the Proceedings of the Royal Institute of
Lombardy of July 19 last.

The Pilot Chart of the North Atlantic Ocean shows that
the weather over that ocean during November was very severe.
From the glh to the 23rd of the month there were only two
days of good weather between Newfoundland and this
country. An appendix to the chart gives the synoptic weather
condilions of the North Atlantic north of the 35th parallel for
six consecutive days (Sejitember 28 to October 3) for the hour
of Greenwich noon, showing the positions and behaviour of
the various storms which were prevalent at that time. The
excellent system adopted by the United States authorities for
the collection and discussion of observations made at sea has
enabled Ihem to produce this synoptic chart so soon after
date. We notice, however, that in the description of the
storm signals used in various countries the "cylinder" or
" drum " is referred to as now being employed by this country,
but as a matter of fact it has not been used for many years.

In La Natto-e of the ist instant, M. de Nansouty gives an
account of some interesting experiments by M. Kcechlin on the
Eiffel Tower, with the view of measuring the force rf the wind
by the use of metal blocks whose resistance had been previously
tested in the laboratory by means of compressed air. During
the storm of November 12 last, the velocity anemometers
registered 100 miles in the hour, and according to the formula
used for the conversion of velocity into pressure, the blocks
indicating a pressure of 200 kilograms ought to have been over-
turned, but only those indicating a pressure of 100 kilograms were
displaced. From this, M. Kcechlin concludes that the formula
gives results about 40 per cent, too high. It appears to us that
the experiments afford a remarkable confirmation of Mr. W. H.
Dines's recent investigations of anemometrical constants, in
which he found that the usual theory of the cups moving with
one-third of the wind's velocity gave values which were about
30 per cent, loo high. Experiments very similar to those of
M. Ktachlin were made by Mr. G. Dines ■^ome years ago, under
less favourable conditions, but with nearly similar results.

-V PICTURE-PUZZLE of a remarkable kind appears in the
Zoologist for December. It is a reproduction of two photo-
graphs of a Little bittern, showing the strange attitudes assumed
by the bird to favour its concealment. One of the figures shows the
bird standing in a reed-bed, erect, with neck stretched out and
beak pointing upwards ; and in this position, it is difficult to dis-
tinguish the bird at all from the reeds. The eye is deceived in a
similar manner when the bird is crouching against a tree-stump
at the river-side. Mr. J. E. Harting thinks that ' the curious
attitudes adopted by the bird, on finding itself observed, are
assumed in the exercise of the instinct of sel f-preservation. Me
mentions a similar habit, observed and described by Mr. W. H.
Hudson, in the case of a .Sjuth American Little Heron, which
frequents the borders of the La Pl.nta, and is occasionally
found in the reed-beds scattered over the pampas. Without
the aid of dogs, it w.as found impossible to secure any speci-
mens of this bird, even after marking the spot where one had
alighted.

The architecture and sculpture of Gastropod shells has often
arrested the attention of naturalists, for, in spite of the infinite
variety of form assumed by the shell, it is in most cases ex-
tremely difficult to perceive any special utility in the nature of
the modifications. A paper by Mr. W. II. Dall, however, in
a recent number of the American Naturalist (No. 335). cer-
tainly tends to clear up two sets of these phenomena, viz. the
Tidges or plications of the columella, and the lira; or teeth of the
outer lip. The author shows that among the fusiform rachi-

NO. 131 2, VOL. 51]

glossathe retractor orcolumellar muscle is longer, and attached
deeper within the shell in the plicated (e.g. .Mitra) than in the
non-plicated forms [e.g. Fustts). The result of this is that in
the former the mantle during contraction is withdrawn into a
part of the shell too narrow to admit it in its normal shape.
The mantle must wrinkle longitudinally ; and the longitudinal
shelly ridges on the pillar and towards the aperture of the shell
are the mechanical consequences of this plication of the secret-
ing surface. Similarly in forms possessing a very extensive
mantle ( Volutidu:, CyprieiJu-) it may be noticed that the outer
lip of the shell is toothed chiefly in those types in which the
aperture is small, and that the denticulation is less marked as
the aperture becomes larger. This is attributed by Mr. Dall
to the (act that as the aperture becomes reduced the mantle mast
become increasingly wrinkled at its exit from the shell, thus
causing the deposition of teeth and lirs on the outer Up [c /.
Cypma). If these features fall under Prof. Lankester's cate-
gory of " responsive characters," the question arises whether the
whole molluscan shell, so far as its shape and sculpture is
concerned, is not simply a combination of such characters.

The first number of a series of hand-lists of the collections
of living plants cultivated in the Royal Gardens, Kew, has just
been received. This part, which contains a list of Polypetahr,
shows that the complete catalogue will be of the highest service
in helping to establish a uniform system of nomenclature, .•^n
immense number of "trade" or "garden ' names have been
reduced to their proper synonyms, and as the woody plants
(shrubs and trees), grown in the open air, are particularly liable
to contusion in gardens, and in nurserymen's catalogues, the
present list is most acceptable. It can easily be understood that
the list " represents the work of many years, and has only been
accomplished with considerable labour." From the preface
we learn that, of the twenty thousand species and distinct
varieties of plants cultivated at Kew, three thousand are hardy
shrubs or trees. Tbe first catalogue of plants cultivated at Kew,
published in 1768, contained 33S9 species, of which 4SS were
hardy trees and shrubs. The two Alton's published similar lists,
but that issued by the younger .\iton early in this century, and
containing about eleven thousand species, was the latest com-
prehensive list of plants in cultivation at Kew, though lists of
special collections have been published from time to time. The
great importance of the series of hand-lists, which Mr. Thiselton-
Dyer has instituted, will therefore be at once understood.

The twenty-sixth volume of the Memoirs of the Russian
Geographical Society (General Geography) contains an i n-
portant work by Prof. Mushketoff and A. OrlolT, being a cata-
logue of all the earthquakes which are known to have taken
place in the Russian empire and the adjoining territories of
China, Turkestan, Persia, and .-Vsia Minor from the year 596
li.c. till the year 1SS7. The list comprises no less than 2400
separate earttiquakes, of which 710 took place in China,
569 in East Sioeria, 36 in West Siberia, 202 in Central Asia,
590 in Caucasia, 121 in North Persia and Asia Minor, and
1 88 in European Russia and Finland. These figures alone, if
compared with those for China in the catalogues of R. Mallet,
A. Perrey, and Fuchs, give an idea of the richness of
the Russian catalogue. As to Russia, Siberia, and Turkes-
tan, the catalogue is replete with entirely new data. Most of
the earthquakes of the last two centuries, for which we possess
full accounts, given by careful observers, are described at some
length, and some of the descriptions, especially for the earth
tremors of Shemakha, Lake Baikal, and Turkestan, are of great
value. A map showing the distribution of the earthquakes
over the territory, and diagrams showing their frequency during
the different months, accompany this most valuable work.

lS2

NATURE

[December 20, 1894

A PArER on the various more or less pliantastic forms as-
sumed by combinations of alkalies with oleic acid when brought
into contact with water, is contiibuted to the current number of
Wiedemann s AiinaUn, by Dr. G. Quincke. Oleic acid with
little alkali, or containing an acid ole.-ne of an alkali in solu-
tion, form in much water hollow spheres, globules, and
foam, with walls of liquid oleic acid. The hollow spaces are
filled with aqueous soap solution. When more water is added,
the walls are covered with a solid skin of the acid oleate, which
may then become quite liquid again by decomposition into
liquid oleic acid and aqueous soap solution. The periodic flow
of soap solution at the surface separating liquid oleic acid and ]
water produces vortex motions, which may be made evident
with methylene blue or other colouring matter. More hollow
spheres and bubbles of oleic acid are formed, which are arranged
by the capillary forces on the larger bubbles in definite posi-
tions, such as straight lines, circles, and ellipses. Dr. Quincke
points out the remarkable analogy between this arrangement
and the configuration of various small portions of the stellar
universe, such as portions of Orion, Virgo, and Coma
Berenice's, and recalls Plateau's experiments with weightless oil
spheres illustrative of the generation of the solar system. He
also emphasises the fact that the protoplasm of the organic
world shows a structure and motions similar to those of oil
loam with liquid or solid surfaces.

Under the title, " Science Teaching ; an Ideal, and some
Realities," Mr. H. G. Wells delivered a lecture at the College
of Preceptors last week. Much attention is now being given
to the methods of science teaching in our elementary schools
and colleges, and Mr. Wells' views on the subject are sound
enough to be taken into consideration. In the course of his
lecture, he pointed out that a rational course of science should
grow naturally out of kinderg.arten. This should lead to object-
lessons proper, and demonstrations in physics and chemistry
may be made to grow insensibly, without any formal begin-
ning, out of such lessons. The best, about the only perman-
ently valuable, preparation for a scientific callmg that can
be given to a boy in a secondary school, is the broad basis of
physics and chemistry led up to io this way.

The 1895 Annuaire of the Montsouris Observator) — the
Observatory of the Paris Municipal Council— has been pub-
lished. Though the observations made at the Observatory
have special reference to the climatology and hygiene of Paris,
researches into the domains of pure science are carried on.
M. Lton Descroix has charge of the physical and meteoro-
logical service, and M. Albert- Levy of the chemical part of
the work. This department includes the study of the variations
in the chemical composition of the air in various parts of
Paris, and of rain and river waters. The third branch of the
work, dealing with micro-organisms, is under the direction of
Dr. Miquel, who contributes to the Annuaire his sixteenth
memoir on the organic matter found in air and water.

The papers read at meetings of the Natural History Society of
Northumbeiland, Durham, and Ncwcastlc-upon-Tyne, and the
Tyneside Naturalists' licld Club, during the past two years,
have just been published in the Society's Transactions, vol. xi.
part ii. Amoni; them is an address by the President, Prof. G.
S. Biady, F. K.S., on the life-history and character of some
internal parasites, and a lecture on parasitism in plants and
animals. The latter forms one of a scries of reports of five
lectures given in the Museum of the Society ; the others being
" On the Egg," by Dr. D. Embleton ; " Frogs and Tadpoles,"
by Prof. M. C. Potter; "The Structure of Timber," by Dr.
W. Sumcrvillc i and "Germs," by Mr. H. Dc Haviland. The
Society appears to be in a far more flourishing condition than
most provincial societies.

NO. 1312, VOL. 51]

Several new editions of scientific books have been received
during the past week. Prof. Richard Hertwig's " Lehrbuch
der Zoologie ' (Guslav Fischer, Jena) is one of these. The
original edition was reviewed in NATURE in June 1893 (vol.
xlviii. p. 173), and we have nothing to add to the remarks
then made, except that the work has been improved by revision.
We are glad to see that Mr. Cumming's "Introduction to the
Theory of Electricity " (Macmillan) has reached a fourth
edition. The chief additions to the new issue are articles upon
the magnetic circuit and on the dynamo. " Symbolic Logic,'
by Dr. John Venn, F.R.S. (Macmillan), has survived the
prejudices of anti-mathematical logician?, for a second edition,
revised and rewritten, has just appeared. Finally, Messrs.
Whittaker and Co., have issued a second edition of "The
Electro-Platers' Handbook,'' by Mr. G. E. Bonney. This
useful manual has been enlarged by an additional chapter on
electrotyping, and by a number of short sections on new
methods of interest to amateurs and young students of electro-
metallurgy.

A Bulletin (really a volume of 259 pages), by Mr. J. E.
Spurr, has come to us from the Geological and Natural History
Survey of Minnesota. The subject is "The Iron Bearing
Rocks of the Mesabi Range in Minnesota,'' and the author
treats it from many points of view. A number of reproductions
of the appearances presented by thin sections of the rocks
when microscopically examined, accompany the memoir.
The matter is not merely descriptive of the general structure
and characteristics of the Mesabi iron-bearing rocks ; if it were,
it would only be of local interest. Space is given to the state-
ment of theories to account for the origin of rocks of the
kind described — a subjectwhich is still one of doubt, discussion,
and speculation. In this connection the origin of glauconite is
dealt with. An examination of a thin section, with a view to
finding whether the forms in which the glauconilic grains some-
times occur have any resemblance to organic forms, led to a
negative result. Mr. Spurr thinks it possible, however, that
further study of more favourable sections may result in finding
traces of the organisms which possibly once existed in the rocks
investigated. His work thiows new light upon several per-
plexing problems in economic geology.

Anhydrous hydrogen peroxide has at last been isolated by
Dr. Wolflenstein in the laboratory of the Technischen Iloch-
schule at Berlin, and the somewhat surprising fact demonstrated
that this substance, which has hitherto been regarded as pos-
sessing but little stability, is capable of actual distillation with
scaiccly any loss under reduced pressure. In attempting to
concentrate solutions of h)drogen peroxide in vacuu by the
method of Talbot and Moody, and also in the open air upon
the water bath, a solution as strong as 66 per cent. Il.jU.,. was
obtained, but with a loss of over 70 per cent, of the oii^inai
amount of peroxide employed. Moreover, it was found that
when the common commercial 3 per cent, solution is con-
centrated, the percentage of ILO^ may be bioughl up to 45
without the loss of any considerable quantity of the peroxide by
volatilisation, but that as the concentration continues to rise
above this limit the volatilisation of the peroxide increases at a
very rapid rale. Fur the great loss was proved not to be due
to decomposition, but to actual vapourisation of the substance.
Evidently hydrogen peroxide is rcniaikably stable at the tem-
perature of a water bath. An attempt w.is therefore made to
actually distil it under reduced pressure. A quantity of com-
mercial peroxide which had been further concentrated until it
contained about 50 per cent. 1I._,0,_. was first puiificd from all
traces of suspended impuriiics, and at the same time still lurther
concentrated, by extraction wiih ether ; alter evaporation of the
ether the solution was found to contain 73 per cent. HjOj.

DECEMliER 20, 1894]

NATURE

181

This solution was then submitted to distillation at the tem-
perature of the water bath and under the reduced pressure of
68 m.m. of mercury. The distillate was received in two-
fractions, boiling at 7i°-8i' andSi°-85° respectively. The first
fraction contained 44 per cent. H,0,„ while the latter was
found to contain no less than 905 per cent. Upon again
fractionally distilling the latter product, a large proportion dis-
tilled at 84 '-85', and this fraction proved to be practically pure
HjOo, containing over 99 per cent, of the peroxide. The liquid
thus isolated is a colourless syrup which exhibits but little
inclination to wet the surface of the containing vessel. When
exposed to the air it evaporates. It produces a prickly sen-
sation when placed upon the skin, and causes the appearance
of while spots which take several hours to disappear again. As
regards the much-discussed and disputed question of the re-
action of hydrogen peroxide towards litmus, Dr. Wolffenstein
finds that even when the pure liquid is made strongly alkaline
with soda and again distilled, the distillate exhibits strong acid
characters, so that the acid nature of hydrogen peroxide must
be regarded as fully established. It is finally shown that the
use of ether in assisting the concentration is by no means
essential. Ordinary commercial 3 per cent, peroxide can be
immediately subjected to fractional distillation under reduced
pressure, and a fraction eventually isolated, consisting of the
pure substance boiling at 84'-85'' under a pressure of 68 m.m.

The additions to the Zoological Society's Gardens during the
past week include a Common Fox {Canis vulpes), British,
presented by Mr. Harold von Lohr ; a Spotted Ichneumon
\HerpesUs nepaUnsis) from India, presented by the Misses
Violet and Sylvia Brockelbank ; two Curlews {Nitmenms
arquatd), British, purchased.

OUR ASTRONOMICAL COLUMN.

Secular Variations of the Interior Planets. — As
far back as 1859, Leverrier discovered that the movement of
the perihelion point of the orbit of Mercury was greater than
could be accounted for by the action of all the known planets,
and he attributed this to the effect of a group of unknown
bodies circulating between the orbit of Mercury and the sun.
Prof. Newcomb has recently gone over the ground again, and
the results of his work are given in Coinptes-rendtis of Decem-
ber 10. A brief statement of the tentative conclusions arrived
at was given in these columns on November 29 (p. 114). From
a discussion of a vast number of observations he has re-
determined the secular variations (or the orbits of Mer-
cury, Venus, the Earth, and Mar*, and he has computed
the masses of Mercury, V'enus, and Jupiter from the periodical
perturbations which ihey produce ; the adopted value of the
earth's mass is deduced from the parallax 8'''8o, and for Mars
the adopted mass is that derived from observations of the satel-
lites, it is then shown that with these masses the calculated
values of the secular variations differ from the observed ones,
the divergences being especially great in the movements of the
perihelia of the orbits of Mercury and Mars, and of the node
of Venus. Two explanations of the differences are open to us :
(l) It may be supposed, as suggested by Prof. Asaph Hall, that
the law of giaviiation.il attraction is not strictly true, and that
the attractive force of the sun varies inversely as the distance
raised to the power of approximately 2 000000 1574 ; (2) they
may be attributed to the influence of unknown masses of matter.

At first sight, the second hypothesis seems preferable, as it
involves no departure from an accepted law, and because it is
the only one which will explain all the secular variations, while
on the first hypothesis the perihelia would alone be affected. If
there are unknown bodies between Mercury and the sun, Prof.
Newcomb shows that in order to produce the observed effects,
their mass must be great enough to produce a sensible
ellipticity in the sun's figure ; and as this has not been detected,
he prefers to place these unknown bodies between the orbits of
Mercury and Venus. He has computed the elements of an
orbit which would reduce all the discrepancies between observed
and calculated values of the secular variations to less than the

probable errors, the mean tdistance being o'48, and the mass .
i/37,oco.oco h that of the sun. At the same time. Prof.
Newcomb re.ards this result more as a curiosity than as a
reality, as it seems improbable that such a group of bodies
should have escaped discovery.

Returning to the other hypothesis, he finds that if we accept
Hall's modification of the law of gravitation, which accounts for
the movements of the perihelia, the variations of the other
elements can all be explained by slightly changing the value of
the earth's mass. The new value corresponds to a solar parallax
of 8"77. Although by no means regarding the latter hypothesis
as established, Prof. Newcomb is inclined to adopt it
provisionally.

Irregularities in Variable Stars. — In a summary of
the observations of variable stars of long period, made by W.
Maxwell Reed at Harvard College Observatory and the Abbot
Academy {Astroit. Joiirn. No. 330), the importance of study-
ing the irregularities in the light curves is strongly insisted upon.
The observations indicate numerous "stand-stills,' or notches
in the light-curves, and these are believed to be secondary
phases produced by additions of light at those points. "A
record of over ten years for T Cephei gives ten more or less
well-defined stand-stills. The mean period is about twenty
days less than that of the variable (about 383 days)." From
studying these and other variables, Mr. Reed is inclined to
believe that " the light-curve, in some cases at least, is the sum
of two or more curves — each component curve having a different
range, period, and character from the others. By such a
hypothesis one can account for the changes in period and
range of a variable, and the presence of "stand-stills" and
secondary phases. Unfortunately, there is not enough evidence
yet to give the elements of the two or more component curves
for T Cephei." It will be remembered that Mr. Lockyer has
.also seen the necessity for supposing more than one source of
variation in many cases, and some of his examples of the peculiar
curves produced by integrating two perfectly regular ones were
given in our columns four years ago (Nature, vol. xlii. p. 550).
With Mr. Reed we regret that less attention has been given by
observers to the character of the light-curves of these variables,
than to the determination of the maxima and minima.

The Radcliffe Catalogue.— The new star catalogue
recently issued by Mr. Stone contains the positions of 6424
stars (or the epoch 1S90, deduced from observations made with
the transit circle at the Radcliffe Observatory between January
I, 1S81, and December 31, 1893. Up to 18S7 a considerable
number of observations were made for the determination of
systematic errors o( the instrument and for errors of the
refraction tables. Since then the observations have been more
exclusively directed to obtaining the positions of stars for well-
distributed zero-points between the equator and N. P.O. 115',
in continuation and completion of the work carried out under
Mr. Stone's direction at the Cape of Good Hope between the
years 1S70 and 1879. The ca ahigue gives the positions of all
stars down to seventh magnitude between the equator and
N.P.D. 115°, except those in clusters; of fainter stars to fill
existing lacunae ; and of many stars of greater N. P. D. than
115° for comparison with the Cape catalogue of 1880. Many
stars north of the equator are also included. The Cape cata-
logue and the present one together give a series of well-distri-
buted zero-points for the whole southern hemisphere. With
refere'nce to future meridian work, Mr. Stone remarks : " Fiom
the facilities which photography affords for the rapid filling in
of the positions of the fainter stars on a phoiographic plate,
when those of a sufficient number of zero-points on the plate
have been otherwise fixed, it would appear that the efforts of
meridian observers will, for the future, be most advantageou-ly
directed to this class of stellar work." The catalogue includes
estimates of proper motions as well as the usual constants, and
there are also copious notes relating to the double and variable
stars. The early appearance of a catalogue entailing such a
vast amount of computation does great credit to the very limited
staff of th«-observalory.

" L'Astronomie." — The decease of this monthly journal of
popular astronomy is announced in the December number.
For thirteen jears M. Flamniarion has conducted /.'.•/j/»tfHtf«;/f,
and has used it to poj ularise, and extend the study of, a>tro-
nomical science, and now it dies hom " difficultcs d'adminislra-
tion." The Societc Aslrcnomique de France proposes to at
tempt to fill the gap by iss.uirg their BttUdin monthly instead
of quarterly, as herelolore.

NO. I3I'?, VOL. 51]

1 84

A^A TURE

[December 20, 1894

ON THE USE OF THE GLOBE IN THE
STUDY OF CRYSTALLOGRAPHY.^

IN modern treatises on crystallography, the crystal is imagined
projected radially on the surface of a sphere, and the
spherical triangles so obtained aie dealt with hy spherical
irigonomeiry. Problems in astronomy and mathematical
geography are also commnnly dealt with by the methods of
spherical trigonometry. But they can also be dealt with
completely by the method of graphical conslrtiction on the
surface of a sphere where the sngles and arcs are directly
measured with a divided circle ; and the use of spherical
trigonometry is dispensed with. Many years ago it occurred to
the author that what elimirated the use of spherical trigono-
metry in the one case might eliminate it in the others : hence
the idea of the use of the globe in the study of crystallography.
Various arrangements of globe and circles were described and
exhibited. The usual method of mounting globes on a polar
a.iis, round which it can revolve inside a metal meridian,
snpporied in its turn at right angles to a horizontal circle or
equator, was found to be inconvmient. It is necessary to be
able 10 reach every part of the globe, and to have it steady for
drawing, and the fixed circle and axes stand greatly in the way
of this. The instrument found most generally use'ul was a
black globe, along with a system of brass circles, divided into
degrees, which can be applied directly and exactly to any part
of its surface. The .system of brass circles is called the
ir.-'ircf'hirt, invented by Captain Aved de Magnac, of the
I'rcr.ch Navy, and published by E. Bertau.x, of Paris. With
this instrument every problem in the ge metry of crystals can
be solved with ease and accuracy by graphic construction alone.
T he various manipulations occurring in the use of the globes
were described and illustrated. In the practical determination
of a crystal, the inclinations of its faces are observed with the
goniometer. From these observations, treated usually by the
methods of spherical trigonometry, the elements of the crystal,
namely, the inclination of its axes and the proportion of its
parameters, are deduced. The process is then reversed, and
the elements found are assumed, and from them the inclinations
of the faces are calculated. The usefulness of the globe was
illustrated by demonstrating how these two processes can be
carried out by simple graphical construction. On the globe,
the face of a crystal is represented by its pole, or the p .int
where the radius of the sphere, which is perpendicular to the
face, pieices the surface of the sphere. The angle between
two faces, measured by the goniometer, is the angle contained
between their normals. It is therefore ready to be transferred
directly lo the globe on which it is entered as an arc. In doing
•so, any point on the globe is taken as the pole of the face from
which a start is made. From this a great circle is drawn in
any direction. When the first angle has been measured on the
goniometer, it is laid off on the globe as an arc, of an equal
number of degrees, along this great circle, and from the initial
fixed point. The poles of the first pair of faces are situated at
the extremities of this arc, which becomes the base line of the
survey of the crystal. By Iriangulation from it, the angles
being supplied by the goniometer, the positions of the poles of
all the faces are placed as points on the globe.

The interred ion of a face with the surface of the globe is a
circle, which may be described on it with a pair of compasses,
lakirg the pole of the face as centre. The circles in whieh any
two faces, which are not parallel, meet the sphere, cut each
other in two points. If lhe>e points be joined by the arc of a
great circle, wc obtain the projection of the edge which the
two faces male on meeting. It is perpendicular to the great
ciiclc passing through the poles of the two faces. If it be
carried parallel lo itself to the centre of the sphere, it coincides
with a diameter, and its poles are indicated by points on the
globe. When the operation has been repeated with all the
edges, wc have a second group of points on Ibe globe, which
catalogue* the edges occurring on the crystals.

If the circles f.f intersection, with the surface of the sphere,
of any three facet, not in the same zone, be considered, the arcs
connecting each pair of intersections meet in a point which is
the projection of the comer formed by the three faces which
meet there. A third group of points, representing corners, is
thus obtained on the globe, and the chaiaclerislics of the
cr)stal ate exhausted.

> Atnlraci of a Paper read before th« Chemical Society, December 6, 1894,
J J. V. Itucharwn. F.R.S.

If the corners be carried parallel to themselves to the centre,
they find themselves already represented by the intersections of
the diameters representing their edges. If the similar poles of
any such group of diameters be connected by arcs of great circles,
a spherical triangle or jiolygon is marked out, and its area com-
pared with that of a hemisphere is a measure of the corner,
just as the arc is the measure of the angle which it subtends.
The secondary figures thus described on the sur'.ice of the sphere
are always difietent from the primary ones. Thus the corners
of the cube, when collected at and radiating from the centre of
the sphere, delineate the regular octahedron, which in its turn,
when similarly treated, delineates the cube. From this point
of view they are reciprocal inversion forms.

Having got a complete projection of it on the globe, the
crystal can be studied. It can be referred with equal ease to any
system of coordinates and to any number of different systems ;
it is only necessary to shift the nu'trosfhh-e over the surface of
the globe. In fact, there is now no question touching the geo-
metry of the crystal which cannot be directly answered alter
making one or more simple measurements ; and the distinc-
tion between easy questions and difiicult ones has almost
disappeared.

The projection of the crystal has been constructed from sup-
posed observed angles on the goniometer ; but it is equally easy
to construct it from its crystallographic specification — that is,
the inclination of the axes and the proportion of the para-
meters.

The projections, of the normals to the faces, or the co-
ordinate planes, are found by constructions on these planes.
These positions are marked on the sphere by the points on the
coordinate circles where they meet its surface. A great circle
drawn through any one point, at right angles to the coordinate
circle, contains the pole of the face. It is also contained in
another great circle, found in the same way. It is fixed in their
point of intersection.

In this way every possible face, permitted by the specifica-
tion, can be easily and readily placed on the sphere by its repre-
sentative pole ; and the angles between every pair can be at
once taken off with a pair of compasses or a tape. In a few
minutes a complete catalogue can be made of the angles which
each face makes with every other one. The advantage of this
is particularly apparent in the oblique systems, which on the
globe are dealt with as readily and as easily as those of the
regular system.

In conclusion, the author alluded to other uses of the globe,
where it does easily, and without fatigue, work which can he done
in no other way without great labour ; and he pointed out an
important indirect advantage, gained by its use. in the education
of the sense of direction, which is generally only sparingly
developed in the mind.

THE USE OF SAFETY EXPLOSIVES IN

MINES.

A LARGE committee wasaoi oinled by the North of England
Institute of Mechanical Engineers in iSSS, to investigate
and report upon the subject of flamelcss explosives in relation
to their dcgrte of safety in mines. Expeiimcnts with various
explosives and appliances connected wiih shot-firing were com-
menced in 1892 at lleliburnupon-Tyne, and a number of
papers referring lo them have been contributed lo the Insti-
tute's Transactions. The first part of the Report of the Com-
mittee has just been puhlished, and it clears away many ol the
doubts and uncertainties connected with the emplo\meiit of
safety explosives in underground workings. Into the detail- of
the experiments we have not space lo enter, but the following
conclusions deduced from them show the kind of results
obtained : —

(1) All the high explosives (ammonite, ardeer powder, bel-
lite, carbonitc, roburiie, and sccurite) arc less liable ihan
bla-tingpowder to ignilc inflammalilc mixtures of air and lire-
damp. Thesi: explosives, however, cannot be relied upon as
en-uring absolute safety when u-ed at places where inllamniable
mixture- ol air and fire-damp may be present.

(2) The variable results following upon the delonalion o' high
explosives appear to be <luc in some measure lo defective ad-
mixture of, or variation in the proportions of, the ingredients
used in ihe manufacture of the explosive.

In view of ihe changes from lime to lime made in the pro-

NO. 131 2, VOL. 51]

December 20, 1894]

NA TURE

•85

portions and constituents of high explosives, it seems desirable
that this iiiformaiion shnuld be afforded by the manufacturers to
the users of the explosive.

(3) In the storage of high explosives, it is desirable that every
care should be taken to insure their being maintained in a
proper condiiion. It i> also certain that these explosives alter
in character with age.

(4) It is essential that similar examinations of the wording-
places and precautions which are in force in mines where hlnst-
ing-powder is used, should be rigidly observed when a high
explosive is employed.

(5) In selecting a high explosive for use in a mine, it should
not be forgotien that the risk of explosion is only lessened and
not abolished by its use.

(6) All of the high explosives on detonation produce evident
flame.

(7) The emission of flame from a blown out shot of a detonated
higti explosive is not prevented by the quantity or length of
stemming used.

(8) In the case of a charge of a high explosive which has
missed fire, if a short length of stemming (proved up to 8 inches)
has been employed, the charge can be detonated by another
cartridge of the explosive and additional stemming being placed
in the hole in lionl of the original stemming.

The experiments were carried out under the direction of Mr.
J. L. Medley, H.M. Inspector of Mines, and Mr. A. C. Kayll,
the Engineer to the Committee.

The sincere thanks of mining engineers are due to the Institute
for bearing the great expense involved by the experiments, and
to the many mining companies, associations, and private firms
that have rendered valuable assistance in the matter.

THE UPSALA MEETING OF THE INTER-
NA TIONAL Mb. TEOROLOGICAL COMMITTEES

A T the meetings of the International Meteorological Com-
■'*■ mitiee, held at the University of Upsala, in August, the
secretary submitted a brief report, with the questions pro-
posed for discussion. A statement of these, with the decisions,
follows :■ —

Inlernalional Buriaic.^K report was presented by Prof.
Hildelirandsson, in which the functions and C'lst of such a
bureau were considered. The committee decided against its
establishment.

Agricultural Meteorology. — Upon the proposition of Mr.
Scott, it « a- decided that the methods employed to distribute
weather predictions to farmers, and the results of climatological
discussions relating to the crops in the various countries, be
published.

Establishment of Stations for Cloud Observations. — Prof.
Hildeb^and^son presented a pamphlet containing a detailed
account of the principal methods employed in these investiga-
liunp. Tfte committee adopted these resolutions: —

Since experience shows that the altitude of clouds can be
easily determined with sufficient accuracy, the generalisaiion of
these invesligalions :n all countries is recommended, preferably
by the use ol the photographic process. Observations of direc-
tion and relative veliiciiy should be made at as many stations as
possible, and measures ol height at a limited number ol suitably
distributed stations.

The value of these investigations would be greatly increased
if made at the same ep ch, therefore it is proposed that they be
commenced May 1, 1896, and continued for one year.

The stations already promised are situated in Balavia,
France, Norway, Portugal, Prussia, Roumania, Russia,
Sweden. United Slates : Blue Hill, and Weather Bureau (six
stations).

Cloud Atlas. — The committee appointed at Munich reported
slightly miidihed delinitions of some types in the Hilde-
brandsson-K6p|ien-Neumayer Atlas, and submitted photographs
and pastels for reproduction in the new atlas, as well as instruc-
tions for observing clouds. These were adopted by the
Permanent Ccmmiitee after discussion and modification.
(See subjoined report.) A special committee, composed of
M. Teis-erenc de Bort and Prof. Riggenbach, with Prof.
Hildebrandsson as chairman, was appointed to publish the
atlas, and the choice of the colour of each place, to represent

1 Extracted from a rep-^rt by Mr. A. Lawrence Rotch, in ihc December
number of the .-hiu-rUan MctioyoU^^ical Journal.

\

NO. 1312, VOL. 5 1]

as nearly as possible the natural conditions, was left to its
discretion.

More Rapid Transmission of Telegrams. — Dr. Snellen pre-
sented a joint report with Dr. Neumayer on this question, in
which the necessity of giving the meteorological dispatches
(rrecedence over others, by opening a circuit system with the
other central bureaus, was urged. The introduction of simul-
taneous observations in the various countries was deemed
necessary. The committee relerred the matter to the Inter-
national Telegraphic Bureau at Berne.

In more or less intimate relation with this question was
a proposition by Dr. van Bebber, on the importance of further
experiments in tele-meteorography. Dr. Snellen explained the
telegraphic transmission of the traces of self-recording instru-
ments by the Olland apparatus, which operates over a short
distance at Utrecht.

.Scintillation of Stars. — At the request of M. Ch. Dufour,
this question, which had been the o ject of investig.itions by
M. Montigny, of Brussels, was brought before the cummitlee.
Further study by him, together with that of M. Ventosa,
on the atmospheric movements observed around stars, was en-
couraged.

Maritime Meteorology: — A proposition of the Russian Admiral
Makaroff, on the necessity of an international convention to
arrange for the discussion of the data contained in ships' logs,
was not approved.

Psychrometric Observations below Freezing. — This question
was introduced by Piofs. Hildebrands.son and Mohn. The
employment of Ekholm's method for the reduction of mean
values was recommended, but a report of further investigations
was recpiesied.

Exploration of Upper Air. — A resolution received from the
Congris de la Science de I' Atmosphere, which had recently met
in Antwerp, on the importance of the balloon ascents now heinr
made at Berlin for meteorological purposes, was confirmed in a
more general sense.

Next Congress. — It was decided to convene a non-official
congress at Paris in September 1896.

The Classification of Clouds.

In the cloud classification of Hildebrandsson and Abercromby,
published in the flildebrandsson-Ivoppen-Neumayer -Vtlas, in
1S90, the word "diurnal" is added to the definition of Group
D, so that it becomes : —

D. Clouds formed by the diurnal ascending currents.
In this way, the cumulus ari>ing from a mass of aqueous
vapour ascending through calm air is distinguished from the
nimbus caused by the general ascension of the whole ma.s of
moist air.

With this change the classification of the ten principal forms
is : —

(<z) Detached or rounded forms (most frequent in dry

weather).
{!>) Wide-spread or veil like forms (wet weatl-er).

A. Highest clouds, mean height 9000 metres.

(rt) I. Cirrus.

(/') 2. Cirro-stratus.

B. Clouds of mean altitude, 3000-7000 metres.

, . ^ 3. Cirro-cumulus.

^ ' ( 4. Alto cumulus.

(b) 5. Alto-stratus.

C. Low clouds, 1000-20CO metres.*

(.1) 6. Strato-cuinulus.
(/') 7. Nimbus.

D. Clouds formed by the diurnal ascending currents.

8. Cumulus. Top, iSoo metres ; base, 1400

metres.

9. Cumulo-nimbus. Top, 3000-5000 metres;*

base, 1400 metres.

E. Elevated fog, below 1000 metres.

10. Stratus.

N.B. — -As the heights of the clouds marked * do not agree
with the heights of these clouds found at Blue Hill, Mr. Rotch
has asked that the altitude of the low clouds be placed below
2000 metres simply, instead of between 1000 and 2000 metres,
since the b.ises of nimbus are frequently below 1000 metres ;
and also t hat t he super ior limit of the tops of the cumulo-nimbus
be raised to 8000 metres.

The following are desciiptions of the clouds, modified from
those in the Hildebrandsson-Koppen-Neumayer Atlas.

iS6

NATURE

[December 20, 1^94

(i) Cirrus (CL). — Isolated feathery clouds of fine fibrous
texture, generally of a white colour. Frequently arranged in
bands which spread like the meridians on a celestial globe over
a part of the sky, and converge in perspective towards one or
two opposite points of the horizon. (In the formation of such
bands, Ci. S. and Ci. Cu. often take part.)

(2) Cirro-Stratus (Ci. S ).— Fine whitish veil, sometimes
quite diffuse, giving a whitish appear.ince to the sky, and called
by many cirrus haze, sometimes of more or less distinct struc-
ture, exhibiting confused fibres. The veil often produces halos
around the sun and moon.

(3) CiRRO-CuMULUS (Ci. Cu.).— Fleecy cloud. Small white
balls and wisps without shadows, or with very faint shadows,
which are arranged in groups and often in rows.

(4) Alto CiMULUs( A. Cu.).— Dense fleecy cloud. Larger
whitish or gteyish balls with shaded portions, grouped in flocks
or rows, frequently so clo-e together that their edges meet. The
different balls are generally larger and more compact (passing
into S. Cu.) towards the centre of the group, and more delicate
and wispy (passing into Ci. Cu.) on its edges. They are very
frequently arranged in stripes in one or two directions.

(The term cumulocirrusis given upas causing confusion.)

(5) AiTo Stratus (A. S.).— Thick veil of a grey or bluish
colour, exhibiting in the vicini'y of the sun and moon a brighter
portion, and which, without causing halos, may produce coroi.a'.
This form shows gradual transitions to cirro-stratus, but, accord-
ing to the mea.'-urcments made at Upsala, has only half the
altitude. . .

(The term stratus-cirrus is abandoned as giving rise to
confusion.)

(6) Strato Cumulus (S. Cu.).— Large balls or rolls ofdaik
cloud which frequently cover 'he whole sky, especially in winter,
and give it at times a wave-like appearance. The stratum of
s'rato-cumulus is usually not very thick, and blue sky often
appears in the breaks through it. Between this form and the
altocumulus, all possible graduations are found. They ate dis-
tinguished from nimbus liy the ball-like or rolled form, and
because they do not lend to bring rain.

(7) NlMiiUS (N.). — kain clouds. Dense masses of dark form-
less clouds with ragged edges, from which generally continuous
rain or snow is falling. Through the breaks in these clouds
there is almost always seen a high sheet of cirro-stralus or alto-
stratus. If the mass of nimbus is lorn up into smaller patches,
or if smaller clouds are floating very much below a great nimbus,
the former may be calkd Fracto-nimbus ("Scud" of the
sailors).

(8) Cumulus (Cu.).— Piled clouds. Thick clouds whose
summits are domes with protuberances, but whose bases are
flat. These clouds appear to form in a diurnal ascensional
movement which is almost always apparent. When the cloud
is opposite the si:n, the surfaces which are usually seen by the
observer are more brilliant than the c iges of the protuberances.
When the illumination comes fiom the side, this cloud shows a
strong actual shadow ; on the sunny side of the sky, however,
it appears dark with bright edges. The true cumulus shows a
sharp border almve and l.elow. It isoften torn by strong winds,
and the detached parts (Fracto-cumulus) present continual
changes.

(9) CUMULO-NIMBUS (Cu. N.).— Thunder cloud ; shower
cloud. Heavy masses of clouds, rising like mountains, lowers,
or anvils, generally surrounded nt the top by a veil or screen of
fibrous texture ("false cirrus"), and below by nimbus-like
masses of cloud. Fiom their base generally fall local showers
of rain or snnw, and sometimes hail or sleet. The upper edges
are either of compact cuniulus-bke outline, and form immense
aammits, surrounded by delicate false cirrus, or the edges them-
selves ate drawn out like cirrus. This last form ismost common
in " spring squalls." The iront of storm clouds of great extent
sometime^ shows a great arch stretching across a portion of the
sky, which is uniformly lighter in colour.

(10) Stkails (S,).— Lifted fog in a horizontal stratum.
When this stratum is torn by the wind or by mountain summits
into irregular fragments, they may be called Fracto-stratus.

Instructions for Observing Clouds.

At each observation there are to be recorded : —
(i) The /Vh./<7/('/i>(M', <lcsignated by the international letters
of the cloud name, which may tie more exactly defined by giving
Ihe number of the picture of the Atlai most nearly representing
the observed form.

NO. 13 I 2, VOL. 51]

(2) The Direction Jrom which the ClouJs tome. — If the
ob-eiver remains completely at rest during a lew stconds, the
motion of the clouds may be easily ob>erved relatively
to a steeple or mast erected in an open space. If the
motion of the cloud is very slow, the head must be sup-
1 ortc-d. Clouds should be observed in this way vmly near the
zeriih, for if they are too far away from it the perspective may
cau-e errors. In this case nephoscopes shiii il he used, and
the rules followed which apply to the particular instrument
employed.

(3) Kadiant Point of the Upper Clouds.— "Y^tf^^ clouds often
appear in the form of fine parallel bands, which, by an effect of
perspective, seem to come from one point of thr hoiizon. The
radiant point is that point where these bands, or th ir direction
piolonged, meet the horizon. The position of ilns point oii the
horizon should be recorded in the same way as the wind direc-
tion, norih, north-north-east, &c.

(4) C'lidiilalory Clouds.— \l often happens that the clouds
show legular, parallel, and equidistant streaks, like the waves
on the surface of water. This is the case for ihc greater part of
the cirro-cumulus, strato cumulus (roll-cumulus), &C. It is im-
porant to note the direction of these streaks. W lun tbeie are
apparently two distinct systems, as is to be seen in clouds
separated into balls by streaks in two directions, ihe directions
of the two systems should be noted. As far as pos-ilile, obser-
vations should be made on streaks near the zeii th to avoid
effects of per-pective.

(5) D, II lily and /'osilion oj Cirrus Banks.— T\\e upper

clouds fiequcntly take the form of felt or of a re o less dense

veil, which, rising above the hoiizon, resembles a ihin white
or greyi-h hank. .\s this cloud form has an intim.tie relation
to baiometric depressions, it is important to note : —

(<i) The density —

0 meaning very thin and irregular.

1 me.ining thin but regular.

2 meaning rather dense.

3 meaning dense.

4 meaning very dense and of dark colour.
(I>) The direciion in which the veil or bank appears densest.
Hemarls.—XW interesting details should le noted, for

example :

(1) On summer days all low clouds generally assume par-
ticular forms resembling cumulus more or less. In ihis case,
there should be put under Remarks, " Slraius or Nimbus
Cuniulilormis."

(2) Il sometimes happens that a cumulus has a mammillated
lower surface. This appearance bhould be dtscribed by the
name of "Mammato-cumulus."

(3) It should always be noted whither Ihe clouds appear
stanonary, or whether they have a verj great velmi ».

The text of the Atlas is to be in French, Eii,;lish,
German.

and

ENDOWMENT FOR SCIENTIFIC Rt-.SEARCH
AND PUBLICAIIO.\.^
II.
IMMEDIATELY connected with .ur colleges and universities
•*■ is another field, in which addi ional endowmem^ ;ire greatly
needed, viz. for fellowships in science for , o-igraduale
studie.s. .

Upon Ihe post-graduate workers the future ol cunce, ana
the recruits for future teachers and piofessors, niusi iccessarily
depend. In that view Ihe imporinr.ce of posi-gn.luaie endow-
ments in science can scarcely be m igmfied. Th. gu-ai majority
of ihe >oung men from whom all the new lec un- must be
drawn have little or no ptcuniaiy n cans. An-r graduating,
ofien through many difficulties, they niiisl face ihc qu si ion of
their future calling. 1 hey must consider whai pioiiiise of «
reasonable and comfortable support a life devoir. i to science
all..rds. If this risk should not d.ter ihein, siill there are
many with talents of a high order who would ic ahsolutely
unalilc to proceed further in ihe advanced scicniific studies
neccssaiy to qualify ihem to enter upon rcmunera ive scicnlihc

' Address Jelivcred by Mr. Addison Brown, at a meeting of ihc Scicnlific
Alliance of New Vorlt. Reprinlcd (rem Smilhsonian K.;porl, \i<)i-
(Continued from pa^e 167.)

December 20, 1894]

NA TURE

187

work, or to obtain situations as professors or assistants, except
by the aid of substantial endowments for their support, during
the three or four years more of necessary assiduous ^tudy.

In the stress o( modern life, and in the allurements towards
more certain pecuniary resul's, noihing but such endowments
can avert the withdrawal from scientific pursuits of many young
men of high promise, whdse genius and tastes and ambition
strongly incline them to science, and who would be secured to
it if this temporary support were afforded.

The endowments of our colleges and universities in aid of
post-graduate work in science are much less, I suppose, than is
commonly imagined. I find no such support for postgraduate
work in scienci", either at C'irnell University, at the University
of the City of New York, ai Brnwn University, at Amherst, or
even at the Johns Hoi'kin- University. No statement of the
endowments of the new Claik University at Worcester has as
yet been published. Princeton, though having a hundred
under-graduate scholarships, has but one post-graduate fellow-
ship for science ; Yale but two — the Silliman and the Sloanc
Fellowships.

Columbia College has two fellowships expressly restricted to
science, viz. the Tyndall Fellowship of 64S dols. annually,
and the Barnard Fellowship, before rc-ierred to, of about 500
dols. annually. Besides ihese, however, twenty-four geneial
university fellowships have been established, of 5C0 dols. each,
for post-giaduate study, of which eighteen are in present oper-
ation. About one-third of ihese are as-igned to science ;
making now eight for science at Columbia, with probably two
more in 1893 or 1894 In architecture, moreover, there are
three addiiiinal noble pos'-graHuate fellowships at Columbia — ■
the Schermerhorn of 1300 dols. annually, and the two McKim
Fellowships o( loooools each, to support study in foreign
travel. In the Medical Dcpariment, also, there are five valuable
prizes for proficiency.

The University of Pennsylvania has the Tyndall Fellowship,
before referred to ; and, m I he Department of Hygiene, an
admirable laboratory fiited up by Mr. Henry C. Lea, with a
fellowship of 10,000 dols. endowed by Mr. Thomas A. Scott, at
present applied to original research in bacteriology.

At Harvard, besides the three Bullard Fellowships of
5000 dols. each, esiablished in 1891, to promote original re-
search in the medical school, there are two post-graduate fellow-
ships reslricted to science exclusively, namely, the Tyndall
Fellowship of about 500 dols. annually, and the income of the
recently established Joseph Lovering Fund, the principal of
which is now about 8000 dols. There are also eleven other
general fellowships, viz. the Parker, the Kirkland, and the
Morgan Fellowships, availal'le for promising graduate students
in any branch, of which about five have been usually assigned
to science. These fellowships give an income of from 450 dols.
10 700 dols. a year. Harvard has also foity-six scholarships
available for graduate sludents, varying in income from 150 dols.
to 300 d'lls. each, of which about seventeen are assigned to
science. During the last \enr, according to the report of Prof.
Pierce, the Dean, theie were 193 applications for those post-
graduate fellowships ai d scholarships, seventy-o e of which
were in science. Only i.ne- third of the applicants could receive
the aid. The Dean adds :

" The number ol appi in>ments is still very insufficient to
meet demands of pr.nn i' g siudents who wish to enier the
graduate scl ool, and are unable to do so without a-sislance. "
(Report Harvard Coll. 1891, p. 92.) The tables published by
him indicate tliat a ccnsidciable number of those not aided
withdrew from science ; and that many others who were entered
for the firsi )ear in the graduate school would, il not aided,
afterwards leave. Ii is graiifying to observe the further fact, so
encouraningalso for the ynung graduates who wish, if possilile, to
enteruponascieniificcaieei,Ihat all who had enjoyed these fellow-
ships tor the lull term of ihree years, andd id not coninue their
studies furiher abroad, ai •■nee received honourable Ipo-iiions.

From the above synoi-is it appears that in all these Colleges
(.md I kiion of no other similar fellowships elsewhere) there
are onl) ab' ut twenty-six adequately endowed post -graduate
fellowshii s in science. As these should be continueil for ai
least three years, there is provision altogether for only about
nine per year — not one f"U ih the number required tosupply the
annual loss in • ur 150 colleges, to .say nothing of the incieasing
demand ihn.ugh the ^ro^^th and improvements in the culleges
Ihemselv. s. As it is Ir m such specially trained students thai
the great piof ^sirsof ihe future must be drawn, the need ol
much greater endowments for new recruits is apparent.

In England the aids afforded by fellowships in their univer-
sities are familiar to all. Sir Isaac Newton, who is to modern
science what Shakespeare is in literature, was sustained from
his student days successively in a .scholarship, a fellowship,
and as professor at Trinity College at Cambridge. Besides
those aids, the Royal Com^uissioncrs of the Exhibition of 1S51
instituted in 1891 " Exhibition Science scholarships 'for ad-
vanced students, to which 25,000 dols. yearly is to be applied
in sutns of 750 dols. each. In the first year sixteen appoint-
ments were made, to be held for two, and probably for three,
years by students who show capacity, and " who advance
science by experimental work." '

On this subject a most interesting discussion took place last
year in the French Academy of Sciences. On April 27, 1891,
the Secretary read the following extracts from the will of the
late M. Cahours, a deceased member of the Academy :

" I have frequently had the opportunity of observing, in the
course of my scientific career, that many young men distin-
guished and endowed with real talent for science, found them-
selves obliged to abandon it, because before beginning they
had no efficacious help which provided them with the first
necessities of life, and allowed them to devote themselves
exclusively to scientific studies.

" With the object of encouraging such young workers, who
for want of sufficient resources find themselves powerless to
finish works in course of execution, ... I bequeath to the
Academy of Sciences . . . 100,000 francs, . . . the interest
to be distributed yearly by way ol encouragement to any young
men who have made themselves known by some interesting
works, and more particularly by chemical researches ; . . .
as far as possible to young men without fortune, not having
salaried offices, and who, from want of a sufficient situation,
would find themselves without the possibility of following up
their researches. These pecuniary encouragements ought to be
given for several years to the same yuung men, if the Com-
missioner thinks their productions have sufficient value ; . , .
to cease when they shall have other sufficiently remunerative
positions."

M. Janssen, then addressing the Academy, said :
"This affords an example to all who hereafter may desire to
encourage the sciences by their liberality. M. Cahours, who
knew the urgent necessities of science, had, like most of us,
become convinced of the need of introducing a new form of
scientific recompenses.

" Our prizes will always continue to meet a great and noble
necessity. Their value, the difiiculy of obtaining them, and
the eclat they take from the illustriousness of the body thai
grants them, will always make them the highest and most
valuable of recompenses. But the value also of the works it
is necessary to produce in order to lay claim to them forbids
them to beginners. It is a held only accessible to matured
talents. But there are many young men endowed with precious
aptitudes, inclined to pure science, but turned very often from
this envied career by the difficulties of existence, and taking
with regret a direction towards more immediate results. And
yet many among them possess talents which, if well cultivated,
might do honour and good to science. . . . These difficulties
are increased every day by the marked advance of the exigencies
of life.

" We must find a prompt remedy for this state of things, if
we do not wish to see an end of the recruitment of science.
This truth is beginning to be generally felt. The Government
has already created institutions, scholarships, and encourage-
ments, which partly meet the necessity. Some generous donors
are also working in this manner. I will mention specially the
noble foundation of Mdlle. Dosne, in accordance with whose
instructions a hall is at this moment being built, where young
men, having sho.vn disiingui-hcd ajitituiJcs lor high administra-
tion, lor the bar, or for history, will receive for three years all
the means of carrying on high and peaceful studies. Let us
say, then, plainly (and in speaking thus ne only feebly echo
the words of the most illusitious members of the Academy),
that it is by following the way so nobly opened by Cahours
that the interests and prospects of science will be most effi-
c.iciously served." -

Huxley is said to have once stated that "any country would
find it to its interest 10 spend ico,ooo dols. in first jinJing a
Faraday, and then putting him in a position where he could do

1 Sir William Thomson, Proceedings^ Koj'at Society, 1891,
p. 225.

2 Nature, May 7, 1891 (vol. x!iv. p. 17).

vol. U

N

12. V L. 51J

iSS

NATURE

[December 20, 1894

the greatest amount of work." It is the post-graduate endow-
ments Ibat must first find and retain to science the Faradays of
the future.

A notable instance of the need and value of such aid is found
in the recently-appointed head of a great university, who, by
such endowments alone, here and abroad, it is said, was en-
abled 10 prosecute his studirs for ten years successively, reach-
ing thereby the front rank in his chosen department of
philosophy.

III.

.■\nothcr department in great need of pecuniary support is
that of the learned and scientific societies. In these England
is pre-eminent. Our own societies have endeavoured to follow,
as far as they could, their English models. The English
societies have rendered to science invaluable service in three
main lines :

1. In providing ample means for the publication of scientific
papers, showing the progress and the results of their scientific
work. In this every society has taken part.

2. In the direct maintenance of original research, in which
the Royal Institution has been most conspicuous.

3. In the award of prizes for sciintific distinction ; but still
more important, in the distribution o( pecuniary aid, for the
prosecution of special scientific researches.

(1) Of these, I regard publication as, perhaps, the most im-
portant ; not only because it puts the world in possession of
what has been done by investigators, but beciuse the very fact
that there are means of publication, is one of the greatest iocite-
mcnis to complete and thorough original scientific work.

Of the Eiglish societies the Royal Society is the oldest,
having been chartered in 1662. It has published 181 volumes
of Tranailions and about 50 volumes of l^rocctdings. For
these purpose', in 18S1 the expenditure was between 11,000
dols. and 12,000 dols. It has property to ihe value of ab lut
two-thirds of a million of dollars, more than half of which is
in trust funds, held tor scientific uses. The income on the trust
funds in 1891 was about 17,500 dols. (Proceedings, 1891, vol. I.
p. 235.) In 1828 Dr. Wollaston, in giving it 10,000 dols.
in 3 per cent. Consols "to promote scientific researches,"
charged upon the Society "not to hoard the income parsi-
moniously, but to expend it liberally for the objects named."

The Royal Institution of Great Britain was founded in 1779,
largely through our countryman James Thompson, of Rumfoid,
Vi., afterwards Count Rumford. In iSSS it had property and
invested funds for general purposes to the amount of 350. 000 dols.,
and about 40,000 dols. of invested funds for the maintenance
of its three professors. In 1887 it expended about 2000 dols.
in publications, and it has issued about forty volumes. (Report,
1888, p. 13.)

The Linnean Society, now furnished by the Government
with permanent accommodation in Hurlington House, free of
rent, was founded by Sir James E. Smiih in 1 788, and is devoted
to botany and zoology. Its nroperty amounts to about 32,000
dols., but it has no endowed funds for scientific investiijation.
For some years past its receipts, mainly from contriliutions,
have been about 10,000 dols. a year, of which one-half, about
5000 dols., is spent on its publications, which now number
nearly fifty volumes of Transactions in quarto, and as many
more of its Journal. In 1888 7000 dols. were expended in
publication. (A'roc^a'iwfy [May 4, 188S], 1890, pp. 15, 45.)

Next in order of lime is the lirilish Association for the
Advancement of .Science, founded in 1831. It is sustained
chiefly by yearly contriliuiions. Its investcil funds amount to
aiiout 62,000 ilols. It» income and contributions are about
10,000 doU. annually, out of which it appropriates from 6000
dols. to 7000 dols. per annum for the encouragement of scien-
tific investigations, and about 1800 dols. annually for its yearly
volume of /'roceeilings. Its publications now number twenty-
five volume.*. (Kef'ort, 1891, pp. Ixxxvii. toe. 76.)

The Kay Society w.as fiundeil in 1844. It was named after
the Rev. John Ray, who lived from 1628 until 1705. Hallcr,
himself one of Ihe greatest men of science of his time, writing in
1771, in Ihe full light of l.innxus' fame, calls Kay "the greatest
botanist within the memory of mm." (Bibliothtca liotanica.)
The society has publisherl about fifty volumes of scientific
works of the highest importance. I have not seen anystntisiics
concerning us means or acquisitions ; nor have I found any
financial report of the Kicnlific societies of Edinburgh or
iJublin.

(2) Of these societies, only the Koyal Institution directly

NO. 131 2, VOL. ,<^ll

supports professors for scientific research. It has two labor.i-
tories, one chemical and one physical. These were rebuilt in
1872, " in order that original discovery might be more elVec-
tively carried on." The society w.-is founded for the declared
purpose of " promoting scientific and literary research." It has
three professors — one in chemistry, one in physics, and one in
physiology. Davy, Faraday, Tyndall, and others who have
spent their lives there, have made its annals immortal.

(31 In stimulating research by the appropriation of moneys
for specific objects, the Royal Society and the British Associa-
tion are the chief .igencies. Besides some of its own funds, the
Koyal Society distributes annually £^a,ooo, or 20,ooodols. , granted
by the Government " for the advancement of science." This
has been done by applying it to numerous purposes ; in 1S91,
for fifty-seven different scientific objects, in sums ranging from
25 dols. to 3000 dols. each ; not confined to natural science
alone, but including ethnology and magnetic surveys. Most of
the grants were in sums of about 350 dols. or less. (Proceeding,
1S91, vol. I. p. 242 )

The British Association has disbursed annually for the last
forty years from 6000 dols. to 7000 dols. per annu n, upon the
same system of dividing it up lor numerous specific purposes;
usually from thirty to forty objects yearly, the grants being in
sums ranging from 25 dols. to 1000 dols. The grants are called
for and expended for the specific purpose named, and under the
direction of some prominent scientific man. Men of science like
Sir William Thomson, and others of like renown, have had the
administration of many of these grants. These have included
for the last six years (save in iSgo) the appropriation of 500
dols. per vear for a table in the Naples Marine Laboratory.
(Report, 1S90, p. 90,)

We have no single .society in this country, save the Smith-
sonian, that can rival in importance those ihat 1 have named
in England. And the Smithsonian is not a society, but an insti-
tution, established by one man, and he an Engli-hman. This
institution, based upon the bequest of James Smiih.-on, was
founded by act of Congress of August 10, 1846. I doubt whether
in any country or in any age the bequest of half a million of
dollars has ever been followed by such beneficent results, or has
ever so profoundly affected the life of science in any country as
the .Smithsonian Institution has done in America during the last
iorty-four years of its existence. I'his has been owing (i) to
the wisdom and the profound scientific insight of Prof. Henry,
its first secretary and director ; and (2) to the corps of able
assistants and successors whom his spirit and policy have
inspired. Its publications number 26 quarto volumes of
"Contributions to Knowledge," 40 volumes of "Mis-
cellaneous Collections," and 44 volumes of "Annual
Reports." Its "Contributions to Knowledge ' rival, if
they do not excel, in rarity and importance, the publications
of any other society during the same peiiod. Its expendi-
ture in publications is about 12,500 dols. a year. Under Prof.
Henry a good deal was done in research. Under Prof. Langley,
the present director, astro-physical research is carried on.
Besides the direct scientific v\oik of the Insiiiulion, however,
its influence ha- been very great, especially in its relations with
the other departments at Washington, and as a mcduini for the
prosecution of ether scientific enterprises under authority of
Congress. Many of the ap|)ropriationsol Congress lor scientific
expeditions for researches in ethnology, i>alxontology, chemistry,
and physics have been due to the jiresencc and co-operation of
the Smithsonian Institution. Fir cilinologic researches alone
during the Last twelve years, under the administration of the
.Smithsonian, Congress has appropriated 400,000 dols. ; to
palxontologic researches within the last three years,
160,000 dols. ; to chemical and physical research, 68, 000 dols. ;
and to astro- physical research, lo.ooodols. Besides these, there
have been for many years appropriations for maintaining the
important investigations of the Coast and Geodetic Survey, and
of the Weather Bureau in Meteorology ; and for Ihe great
scii niific work of the Naval Observatory, and of the various
scientific divisions of the Agricultural Depaitmcnl and of the
Geological Survey. Our Government has been by no means
inactive in science.

The princiial American scientific associations, omitting those
of comparatively recent origin, are the Ameiican I'hili sopliical
.Society of Philadelphia, originally founded in 1744; the
American Academy of Arts and Sciences at Boston ; the
Boston .Society of Natural History : the Academy ol Natural
Sciences', and the Franklin Institute at Philadelphia, the latter

I

December 20. 1894]

NATURE

189

founded in 1824 'see Journal, vol. i. pp. 71, 129); the New
York Academy of Sciences ia continuation of the Lyceum of
Natural lli^tiiry) ; the National Academy of Science at Wash-
ington, founded in 1863 ; and the American Association for
the Advancement of Science. Of these, the Philosophical
Society has published 29 volumes of its Transactions : the
American Academy, 26 volumes of Transaclioiis and 9 quarto
volumes of Memoirs; the Boston Society of Natural History,
25 volumes, at a cost of about 600 dols. per year ; the Academy
of Natural Science of Philadelphia, 48 volumes of Proceedings
and 12 quarto volumes of its Journal, at an average cost of
about 1000 dols. per year ; the Franklin Institute, 133 volumes
of lis, Journal : the New York Academy and its predecessor,
about 30 volumes of Transactions and Annals ; the Na'ional
Acadf my, 3 quarto volumes of Memoirs and some volumes of
Proceeilings : and the American Association for the Advance-
ment of Science, about 40 volumps of Proceedings

The latter society had in 1891 a "Research Fund" of
5254 dols. {Proceedings, 1891, p. 441.) None of the other
socitties, so far as I can find, has any fund specially devoted to
re-earch, or makes any specific appropriations therefor. The
National Academy and the Academy of Philadelphia have each
some funds for their support, and the latter also the Jes-up
Fund for students in science, on which the income is aliout
550 dols. yearly. The Philosophical Society from time to time
awards the prize established by John Hyacinth de Magellan in
1786— an oval gold plate "for the most useful discovery or
invention in navigation or science." One of the eailiest
awards of this prize was for painting lightning-rods with black
lead.

The American Academy of Arts and Sciences awards a gold
and silver medal from a bequest of 5000 dols. made to ii by
Count Rumford, who in 1796 made a similar bequest to the
Royal Society. In l88S this prize was most worthily awarded
to Prof Michelson for his researches in light. ^

The Boston Society of Natural History has a general fund, of
which the income is about 6000 dols. It has al o a small
Walker prize fund and a grand prize fund, from which in 1S84
it awarded a grand prize of 1000 dols. to James Hall, of Albany,
**for his distinguished services to science." It also administers
the expenditure of about 2700 dols. a year for instruction in
laboratory work, drawn from the Boston University, and
1500 dols. from the Lowell Fund for the instruction of teachers."

From this comparison of the voluntary associations, it appears
that the property, endowed funds, and equipment of the English
societies named are nearly tenfold greater than the American,
and their publications double; while for direct original research
our societies maintain no laboratories and no professors, as is
done by the Royal Institution. The English socitties distribute
yearly from 25,000 dols. to 30,000 dols. for from sixty to
seventy-five difierent scientific puiposes, while ours make no
such appropriations, simply becaus- they have no funds. To
supply this deficiency there is need ol large endowments.

The publications of our societies are valuable ; the papers
have often been of a high character, rivalling those published
abroad. But the funds available for publication are insuffi-
cient ; it is always a ipiestion of means. There are a press and
surplus of valuable scientific matter, which cither is not printed
at all, or only gets printed by special subscriptions for the pur-
pose. This ouj;ht not lo be. After valuable original matter
has been produced with great pains and without hope of
pecuniary reward, nothing is more discouraging to future
research than that even publication can only be had as a
charity. This I know, from repeated personal applications, is
the condition of things in New York at this moment. It is n<it
creditable that, in a State and country like ours, there should
be practically nowhere adequate provision for even the pub-
lication of the re-e^rches of those who work for nothing but
their love of science and its progress. There is very gieat need
of a considerable pu''licaiion fund, in the hantis of some scientific
body, through which every valuable contiilnuion to science, not
otherwise provided for, might be ensured a speedy publication,
after it has been found worthy, as in the practice of the Linnican
Society, first by a criiical expert in the particular department,
and then by the council of publication.^

The stimulus, moreover, to scientific research that would be
imparted by the distribution of comparatively small sums, such

* President t.ovcring's Address, Proceeding's, vol. xxiv. p. 380.

- l'rocceiihtg;s, vol. xxiv. p. 14

3 President Carrulhers, Proceedings, Lin. Sac, May 1893, p. 39.

NO. 1312, VOL. 51]

as are given by the Royal Society and by the British Associa-
tion, would also be very great ; nor is there any reason why the
founding of professorships for the express purpose of prosecut-
ing original research in our scientific societies, after the model
ol the Royal Institution, should not in time be followed by
results equally brilliant, and equally beneficial to mankind.

I have endeavoured to point out three main directions in
which there is urgent need in this country of pecuniary endow-
ments.

(1) In relief of professors during the transition of the colleges
from the schoolmaster system to the university sy-tem, whereby
all professors in science shall become actively enlisted in the
prosecution of original discovery as a part of their duties.

(2) In providing for the future recruits in science, by more
endowments for post-graduate study.

(3) By endowments of our scientific associations, both directly
to promote original research, and especially also to supply
larger means of publication.

It is gratifying to perceive what beginnings have been recently
made in response to the needs of science. Only a short time
since, in 1S85, Mrs. Elizabeth Thompson, of Stamford, Conn.,
gave 25,000 dols. to a board of tru>tees of which Dr. Bowditch,
of Bosioii, is president, for the "advancement of scientific
research in its broadest sense." The income is annually dis-
tributed in sums of from two hundred to five hundred dollars.

Mr. H dgkins, of Setauket, Long Island, has bequeathed to
the Smihsonian Institution 200.ooodol5., the income of one-
half of which is to be devoted to research into the properties
of atmospheric air.

Columbia College has, during the year 1891, received from
Mr. Da Costa's estate, before referred to, 100, coo dols. for
biology ; Harvard, the Joseph Lovering Fund, above stated ;
lo.ocodols. from Henry Draper for the photography of stellar
spectra ; the endowments in archaeology, above named ; and
some smaller gifts for various scientific purposes. The Uni-
versity of Chicago and some other institutions have also received
important gifts, not to mention those yet to be realised to other
collrges from the estate of Mr. hairweather.

By a beq lest of Charles Lenning, the Academy of
Sciences of Philadelphia will, in time, receive 20,000 dols. ;
while half a million of dollars will go to the University of
Pennsylvania in aid of instruction in theoretical and practical
mechanics, and 200,000 dols. to maintain schobrships. At this
Universiiy, also, a superb structure for the " Wistar institute
of Anatomy" is now building by General Isaac J. Wistar, at a
cost of about 200.000 dols., including endowments designed for
original research.'

Our reliance in this country must be mainly upon private
endowments and the intelligent appreciation of the needs of
science. The national Guveinment has done, and is doing,
much in certain directions. But aside from the dispositions of
legis!ators, it is restricted by the provisions of the Federal
Constitution, and by delated questions of constitutional right.
State aid is not thus hanipertd ; but Stale aid is difficult to
obian, to any adequate degree, on account of the previous
habits, prejudices, and political training of the people. No
doubt this ought not so to be. The Stale of New York ought,
abstractly considered, to maintain one university of the first
class equal in every department lo any in the world. But the
multiplication of institutions already existing, local jealousies,
and aversion to State taxation, make this now probably im-
practicable.

The remedy is with the people, and through their own volun-
tary methods. It is the people who have made our Govern-
ment, its institutions, its methods, and the great aggregate,
whatsoever it is, such as we see it to-day. Wealth is rapidly
accumulating ; much of it in the hands of those who, spring-
ing from the people, bear the love of the community in their
hearts ; and when they and the people at large shall come to see
that the cause of scientific advance and the discovery of all new
truth are in the deepest sense their cause, responses will, I
believe, coine to every urgent need ; until the work of the
people, by its own methods, shall, even in science, be able to
confront, without shame, the best work of the monarchies of
the Old World.

1 Since the above was written an additional million of dollars lias been
given by Mr. John D. Rockefeller 10 the University of Lhicago, malting
3,6oo,ooodols given by him alone to that institution within less than three
ye.irs, a munificence hitherto unexampled in private cndowiiienls, some
portions «.f which, it is hoped, will be available for the maiDtenance of
original scientific research.

190

NATURE

[December 20, 1894

SCIENTIFIC SERIALS.

American Journal of Science, December. — Inversion of
temperatures in ihe 26 68 day solar maenetic period, by Frank
H. Bigelow. The northern low-pressure and the southern
high-pressure be Its of North America vary in latitude directly
with the solar magnetic intensity, being further north at the
maximum and further south at the minimum of the period ;
whilst the northern high and southern low-pressure belts vary
in the opposite manner. This means that an increase of solar
magnetic intensity generates the cyclones further south, and
causes the anti-cyclones from the polar circulation to travel to
the south. — Remaiks on colloidal silver, by C. Barus. Col-
loidal silver possesses properties which can be explained with
reference to the analogous behaviour of suspended sediments,
allowance being made for differences in the size of particles.
The high degree of insulation detected in Carey Lea's metallic
mirrors may be interpreted as an instance of the altered be-
haviour of non-co herent metallic matter. —Resonance analysis of
alternating curre nts, by M. I. Pupin. Part ii. Closed magnetic
circuit transfer mers distort the primarv current considerably
more than trans formers with open magnetic circuits under equal
degrees of magnetisation. A ferric self-inductance in circuit
with an alternator which gives a simple harmonic E. M.F.
distorts the current by introducing higher odd harmonics, prin-
cipally the harmonic of three times the frequency of the funda-
mental. Rota ry magnetic fields produced by reasonably well-
constructed machines are not accompanied by fluctuations in
their intensity. —.An improved form of interrupter for large
induction coils, by F. L. O. Wadsworth. The interrupter
consists of a brass wheel about six inches in diameter, with
two insulating and two contact segments placed in its circum-
ference, and mounted directly on the shaft of a small electiic
motor making about 1200 revolutions per minute. Twocopper
brushes are made to bear on the hub of the wheel and its cir-
cumference respectively. The hub and the conducting sectors
are in one piece. The insulators are made of slate.

Wiedemann's Annalen der IVtysik iind Chemie. No. 12.— On
the measurement of surface tension of water in capillary tubes
of different glasses, by P. Volkmann. A good wetting capacity
maybe insured bysoakirg the glass tubes in caustic pot.ish, and
then washing with distilled water. That the tubes are perfectly
wetted is shown by the perfect mobility of Ihe line of contact.
The more nearly circular the section of a lube is, Ihe more does
the value of the surface tension of water approach 7-38 mg/mm.
at 20-2'' C, whatever the kind of gla=s. Tubes of very small
diameter give larger values.— On Ihe thcrmochemical processes
in the secondary cell, by Kranz Sireintz. The following
thcrmochemical equations were derived from the author's
experiments :

PbO, + H5SO, aq = PI)SO, -f Aq -f 767 K
PbO, -f SO, gas = PbSO, -f 844 K

PbO, -f H, gas = PbO -)- HjO + 583 K
PbOj = PbO -f O gas- loi K

TheE.M.F. resulting from these equations is I 885 volts. Oneo
the cells worked with, that having the least concentration, gave
1-90 volts.— On the magnetisation of iron and nickel wires by
rapid electric oscillations, by Ignaz Klemencic. The strong
damping action of magnelisable metals upon electric oscillation
i.s explamed by their circular or transverse magnetisation, which
crowds the oscillations into the surface layers much more than
in the case of other metals. Hence the resistance of a
magnetisabic wire to electric oscillations is much greater than
that of another of equal conductivity. This resistance was
determined by studying the development of heat in the wire by
means of a thermo couple. The permeabilities of the metals
deduced by the formul.-i- of Lord Raylcigh and Stefan were :
Soft iron, 118; steel pianoforte wire, soft 106, hard 115-
licssemer steel, soft 77, hard 7.} ; nickel, 27. These are very
near the values found by Ilaur and Lord Raylcigh for feeble
magnetising fields.— Studies of the cicclric resonator, by V
Drude. The author shows that a Hertzian reionator must be
chiefly affected by the electric forces pl.iying at that part of Ihe
resonator circuit which lies opposite the gap, and proves (his
experimentally. The resistance of a Zchnder vacuum tube
used in these experiments was incidentally found to be 2870
million ohms when the interruplor made 25 breaks per second.
NO. 13 I 2, VOL. 51]

SOCIETIES AND ACADEMIES.

London.

Entomological Society, Decembers. — Capt. H.J. Elwes,
President, in the chair.— Mr. F. Merrifield exhibited hybrids
belonging to the genus Satiirnia, obtained by Dr. Standfuss, of
Ziirich ; viz. a male and female hybrid from a male o{ Satiiniia
favonia and a female of Saiurnia pyri, to which he had given
the name of Satiirnia emilia: : also hybrids from what Dr.
Standfuss described as " a male of Callimorpha dominula, var.
persona " (received from Tuscany) and a typical female of
Callimorpha dominula, to which he had given the name of
romanimi. Mr. Merrifield remarked that the so-calUd var.
persona differed entirely from the type of Callimorpha
dominula. — Mr. J. W. Tutt exhibited, and re.id notes on,
specimens of a very small form of Euchlo<\ taken in Shropshire
by the Rev. F. B. Newnham, who was of opinion that it was
distinct from E. cardamines. He pointed out that it w.is much
smaller than the latter species, and that the discoidal spot was
placed as in E. turritis and E. i;runcri at the juncture of the
orange and white spaces, and not, as in E. cardamincs, well
within the orange tip. Mr. Tutt also exhibited, and read notes
en, specimens of Noctua dahlii, from Cheshire, Essex, York-
shire, Aberdeenshire, and other counties. The variation in
the specimens was said to be partly due to their geographical
distribuiion. Herr Jacoby read a letter received from Mr.
Buxton Ferman, one of the Assistant Secretaries of the Post
Office, to the effect that the Postal Union had decided to make a
rule net to allow natural history specimens to be sent by sample
post, which was intended for the transmission of hoiui jide IrdLit
patterns or samples of merchandise, and consequently th.it the
forwarding of such specimens at the sample rate would in
future be irregular. Lord Walsingham, F. R.S., stated that he
had had a long correspondence wiih the Post Office authorities
on the subject, and that the late Mr. Raikes, when Postmaster-
General, promised him in 1891 that such specimens should, so
far as the British Post Office was concerned, be transmitted at
the sample rates ; and a letter to the same effect, from the late
Sir -Arthur Blackwood, when Secretary of the Post Office, was
published in the Proceediiij^s of the Society for 1S91. — Mr. C.
G. Barrett exhibited, for Mr. A. J. Hodges, a specimen of
Hydrilla paluslris, from Wicken Fen, also specimens of
Caradriua amhi-^ia, from the Isle of Wight. I le remarked that
one specimen of the latter had the hind margin of the right
fore-wing indented, and the wing broadened as though from an
injury to the pupa. In this wing the margins of the large
orbicular and reniform stigmata had become so joined that
the dividing lines had disappeared, and the stigmata were
fused into one irregular blotch. — ^Ir. McLachlan, F.R.S.,
exhibited, on behalf of Mr. G. F. Wilson, F. R. S., a "grease
band " which had been tied round trees to prevent Ihe
females of Cheiviatobia hrumata from ascending the trunks
for the purposes of oviposition ; the band was thickly
covered with the bodies of Ihe females, to;,'clher with a
few males. — Surgeon-Captain .Manders exhibited a pair of
Chelura Idfasciata, from the Shan States, and c.illed attention
to the "assembling" habits of the males, some hundreds of
which were attracted by the numerous females which emerged
from the cocoons at sunset.— Mr. B. A. Bower exhibited a
beautiful variety of Zygcena lonicei.c, Esp.. having the spots
confluent, taken at Chattenden Wood, North Kent, in June
last. — Mr. H. Goss exhibited, for Mr. F. W. Uricli, of Trinidad,
a series of males, females, and workers of .Seriomyyme.x opacus,
Mayr., a species of fungus-growing and fundus eating an!. —
Colonel Swinhoe read a paper em it led " A List of the l.epidop-
t,ra of the Khasia Hills, Part III." — Mr. C. J. Gahan read a
paper entitled " On Ihe Longicorn Cokoplera of the West India
Islands." — Mr. F. W. Urich communicated a paper entitled
"Notes on Ihe F'ungus Growing and E.ating Habit of
Scricomyrmcy opacus, Mayr."— Prof. E. B. I'oulton, F.K.S.,
read a paper, by Prof. E. B. Titchener, entitled "An apparent
case of Sexual Preference in a male Insect."— The Rev. H. S.
Gorham communicated a paper entitled "Notes on Herr A.
Kuwcrl's Revision der Cleridengallung Omailius, Lap."

Geological Society, Decembers. — Dr. Henry Woodward,
F. R.^., President, in the chair. — Supplementary note en the
Narborough district (Leicestershire), by Prof. T. G. Bonney,
F.R.S.— The tarns of Lakeland, by J. E. Marr, F.R.S. The
author had examined several tarns of the English Lake district.

December :o, 1894J

NA TURE

191

In those cases where the stream issues from the tarn over solid
rocli, he found either (i) direct evidence that the tarn resulis
from the blocking up of part of a pre-existing vallev by driU,
causing the oefl' ciion of the water to a direction different from
that of the original stream in this locality ; or (2) evid'-nre
which is perfecily consistent with such an explana'ion <if ihe
origin of ihe larn. Umler the circumstances he submiiied that
tarns cannot be assumed lo lie in rock-basins simply because ihe
issuing stream flows over solid rock (and this assumpiiin has
been made), tmt that those who maintain the existence of such
rock-basins must pr .ve the occurrence of solid rock entirely
around the tarn. — Description of a new instrument for survey mg
by the aid of photography, with some observations upon the
applicability of the . instrument to geological purposes, by J.
Bridges Lee. The instrument described in this paper consists
essentially of a photographic camera fitted inside with a mag-
netic needle, which cairies a vertical transparent scale divided
and numbered to 360°, and also with cross fibres which intersect
at right angles. The fittings and adjustments of the instrument
are of such a character that the camera can be accurately levelled
and directed towards any point in a horizontal direction, and
when a photograph is taken in an ordinary way the bearing of
the median vertical plane which bisects the instrument through
the photographic lens will be recorded automatically on the f.ice
of the photograph. The vertical fibre (and its image on the
photograph) serves as an inde.i to read the bearing ; and the
same fibte marks by its shadow a line right across the photo-
graph, which marks the median vertical plane on the imat;e.
The horizontal fibre is adjusted to mark on the imagi, the hori-
zontal plane which bisects the photographic lens. -The marble
beds of Natal, liy David Draper.

Royal Microscopical Society, November 2i.— Mr. A. D.
Michael, I'resident, in the chair. — Messrs. Swift exhibited and
described a microtome, which was made as an improvement on
the Cambridge rocking microtome. The chief features were
that the razor could be fitted at any angle that might be found
best suited to the substance it was desired to cut, that it was
possible to cut sections embedded in celloidin in spirit, and
that it could be u^ed with the ether-freezing apparatus. Messrs.
Swift also exhibited an improved example of tlieir new mechan-
ical stage. The milled heads of the stage were now placed on t he
same side ; the stage had also a greater lateral movement than
in the first examples. — Dr. Measures exhibited a new mechan-
ical stage by Messrs. Zeiss. He considered that it would be
found to be better protected than the old one, and it would
admit a much larger plate. It was also fitted with verniers in
both directions reading to 1',. of a millimetre. — Dr. \V. A.
Turner gave a lantern demonstration on recent methods of
staining sections of the central nervous system. — Mr. E. M.
Nelson described a simple method for measuring the refractive
indices of media. He also described a new reflecting camera
lucida, and a portalile microscope by Zentmayer.

Zoological Society, December 4. — Henry Seebohm,
Vice-President, in the chair. — A communication was read fiom
Mr. T. Manners Smith, on some points in the anatomy of the
water-mole {Oritithorhynchiis paradoxus). The paper relaed
chiefly to the muscular anatomy of Ornithorhyiichtis, which
was followed by a short description of the tiunk-arterial system.
As regards the anatomy, Mr. Smith appeared to have worked
out for the first time the comparative morphology of the skeletal
muscles of the Monotremes as determined by their innervaiion.
— Mr. F. E. Heddard, F. R. S., read a paper upon certain points
in the visceral anatomy of Omilliorhyndtiis. The paper dwelt
in the first instance with the existence of a free fold passing
from the bladder to the liver, where it became continuous with
the falciform ligament of the liver. This fold, however, ex-
hibited no traces of an anterior abdominal vein. The author
also gave a description of the right auriculo-ventricular valve of
the heart. In two hearts examined by him the septal flap of
this valve was complete, though less conspicuous than the free
flap, owing to the fact that it had either no papillary muscles
attached to it, or that the muscles were very small. - Mr.
Boulenger read a second report on additions to the Lizard
Collection in the Natural History Museum. — Prof. F. Jeffrey
Bell called attention to the acquisition by the Natural Uiitory
Museum of some specimens of remarkable corals of great size
from North west Australia, of which he showed some admiralile
photographs taken by Mr. Percy Highley. Prof. Bell urged
the necessity of the acquisition of large specimens of corals,
before coming to any conclusion as to their specific distinctions.

NO. I312, VOL. 51]

Paris.
Academy of Sciences, December 'O-j^I- ^oe^vy J" 'he
chair —The Secretary announced the death of M. Tchebichel,
foreign associate, on December S.-The decease of M Fer-
dinand de Lesseps, on December 7. "as referred to by the
President, and the meeting adjourned, after receiving the cor-
respondence, as a mark of respect for the deceased member.-
A study of the different varieties of graphite, by M. Heiiri
Moissan. Any variety of carbon may be converted into graphite
by sufficiently raising the temperature. This graphite may be
amorphous or crystalline. Its specific gravity vanes ^om 210
to 2''5. Its ignition point in oxygen IS about 660. Its stability,
as evidenced by its resistance to transformation into graphitic
acid, depends on the temperature to which it has been raised.—
A survey made by means of photography, for the delimitation of
the frontier between Alaska and British Columbia by M.
Laussedat.— On the secular variations of the orbits of the lour
interior planets, by Prof. S. Newcomb. (See "Our Astro-
nomical Column.")-On a new ossiferous cavern discovered
at Pointe-Pescade, to the west of AlgerSaint- Eugene, by
M A. Pomel. There appears to be no trace of man or of
the monkey, though numerous other species of animals are
represemed in the remains.-On the solution of nutnerical
equations by means of recurrent series, by M. K. 1 errin.
—On the composition of linear forms and congruences,
by M Stoufr.— On elimination, by M. Hadamard.— On the
law of resistance of air, by M. C. Chapel. A claim to
priority over M. Vallier in regard to the empirical laws recently
enunciated by the latter.— An experimental theory of the clip-
ping and punching of metals, by M. Ch. Fremont. A machine
is described with which the author has succeeded in registering
the work done during punching operations on an indicator dia-
cram.— Integration of the equations of light in transparent and
fsotropic media, by M. E. Carvallo. -Electromotive force of
magnetisation, by M. D. Hurmuzescu.-Determination of the
proportions of carbonate of lime and carbonate of magnesia in
earths, ashes, &c., by M. Albert Trubert. A description of a
simple indirect analysis.— The phosphate of the Gr.ande
Connetable, by M. A. Andouard.-On pectase and pectic
fermentation, by MM. G. Bertrand and A. Mallevre. The
conclusions have been arrived at, that (i) this ferment is iiot
able to coagulate pectin when acting alone ; (2) it produces this
transformation only in presence of -salts of calcium, barium, or
strontium ; (3) the precipitate produced is an alkaline-earthy
pectate.— On a new process for the purification of alcohols,
sugars and a certain number of other organic matters, by M.
E.°Maumenc.— Influence of radiation at low temperatures on
the phenomena of digestion ; FrigotherapfUtics, by M. Raoul
Pictet.— On the morphology and classification of the Coccidians,
by M. Alphonse Labbe.— Succession of the lower ler'iary
strata in the cretaceous protuberance of Saint-Sever, by M. L.
Reyt —On the calcaires ,i lUhothamnium of the valley of the
Chellif, by M. Repelin. -Influence of the dryness of the year
1893 on the forest vegetation in Lorraine, by M. Henry. The
production of wood for 1893 w.-is but 30 to 76 per cent, of the
normal yield.— The ascension of the balloon Archimede
(October 11, 1894). Comparative thermcmietric and hygro-
metric diagrams of the aerostat gas and ihe surrounding atmo-
sphere, by MM. Gustave Hermite and Georges Besan^on.

Berlin,
Physical Society, November 16.— Prof, von Eezold,
President, in the chair.— Prof. H. W. Vogel spoke on
the perception of colours, and demonstrated the various
effects which monochromatic illumination has on a series
of pigments. The effect of two coloured lights on the
several pigments was specially interesting. Thus, for in-
stance, red or yellow squares illuminated by yellow and red
light appeared to be white and grey ; under yellow and blue
they appeared to be red, and in yellow and green lights they
appeared the same as when illuminated by white light. Dr.
Rubens gave an account of experiments carried out on a large
scale in conjunction with W. and E. Rathenau on telegraphing
10 a distance without wires. They were based, in contra-
distinction lo those of Preece, on the principle of the distribu-
tion of currents in the conducting earth. On the banks of the
W.annsee, near Potsdam, two electrodes were sunk in the water
at a distance from each other of 500 metres, and a current from
fifty-five accumulators placed on the bank was sent through
them. From each of two boats connected by a cable an.

192

NATURE

[December 20, 1894

electrode was immersed in the water, and a telephone inserted
into the connectiin. When the current from the accumulators
on the bank was broken, this produced in effect on the telephone
audible at a distance of 4 '5 kilometres. Small islands lying
between the shore and the boats had no influence on the trans-
mission of the sienals.

Meteorological Society, November 6. — Prof. Hellniann,
President, in the chair. — Dr. Meinardus spoke on sheeiliftht-
ning and the various theories in explanation of this phenome-
non. He sided with the view that it is due to a thunderstorm
of which the lightning is visible, whereas the thunder does not
reach the observer owing to total reflection brought about by
refraction in the several superimposed Layers of air. — Prof, von
Danckelman spoke on the climate of Jalu, on the basis of ob-
servations made by Dr. Steinbach since the beginning of 1893
with accuiaie sel(-regisieringinsiiuments. Among the peculiari-
ties of the climate, which is continuously and uniformly warm
and moist, it is more especially remarkable that thunderstorms
and heavy rainstorms occur most usually between 9 and 10
o'clock in the morning. This phenomenon has not as yet been
observed anywhere else.

Physiological Society, November 9. — Prof, du Bois Rey-
mond. President, in the chair. — Dr. Levy.Dorn spoke on the
effect of various temperatures on the secretion of sweat, and
communicated the re.-ults o( his own experiments on cats, deal-
ing with the secretion of sweat al low temperatures. The sweat
glands themselves were kept at the temperature (ig'-So" C.)
most favourable (or the secretion, while the animal's body
was cooled by wati r at 6° C, and secretion was obtained as a
result of dyspnoea, notwithstanding the coolmg of the body.
The 5.ime speaker further gave an account of experiments made
with a view to testing Prof. Grutzner's assertion that heat acts
only on centripetal and vasomotor nerves, but does not affect
motor or ceniiifugal nerves. Carefully observing all the ex-
perimental conditions described by Griiizner, he had found that
the action ol heat on the sciatic nerve leads to a copious secre-
tion of sweat on the cat's paws, that is to say, stimulates centri-
fugal nerves. — Prof. Zuniz criticised the objections raised by
Bohr and Ileniiquez against his experiments on the measure-
ment of the woik done by the heart, and showed up the errors
which had ctept into their observatiins. He next demonstrated
the apparatus he had employed for measuring the amount of
blood forced out by the heart.

New South Wales,

Linnean Society, October 31. — Prof. Haswell, Vice-Pre-
sident, m the chair. — Notes of a visit to the island of Erro-
manga. New Hebrides, in May 1894, by Sutherland Sinclair.
— Preliminary communications on the cerebral comuiissurts of
the mammalia, with special reference to Monotremaia and
Marsupialia, by G. Elliott Smith. From an examination of
the brain in paiypus, Echiiiria, Peramcles, kangaroo, wallaby,
kangaroo ral, Daiyums and phalangisia, (lie superior commis-
suieol the ctrcbrum was shown by ihe author to be homol guus
with the p^allciium o( Placentalia, and not with the corpus cal-
losum. 1 here appears to be no true corpus callosum (as distinct
from a psalierium) in any monoircmc or marsupial. The hook-
like appearance of the hippocampal commissure in sagittal sec-
lion ill marsupials, which led Flower to regard it as corpus cal-
losum, was said to correspond to the shape of the hippocampus,
which IS coextensive with the laieral ventricle. In platypus
only the dor-al limb ol the hook is piesent, because there is
only a rudimentary descending horn ul the ventricle and hippo-
caiupiu. In Euilicria only the ventral limb persists, beciusc
the upper and anterior part of the hippocampus disappears to
allow a corpus callosum to appear in the situation occupied by
the dorsal limb of the hippocampal commissure in Mcialhciia,
i.e. ventral tu Ihe aicu.> uiarginalis. The fascia deniata, as a
consequence of this, is cscniially mf-racollosal. A doubt was
expressed as to ihe presence ol any structure in the subniain-
malia slricily homologous to the Kuihcrian Corpus callosum.
The hypothesis was advanced that the latter slrucmre appears
(just as the hippocampal comiiiis>ure ilocs .somewhat e-iriicr) to
supply the dcinand for a shorter connecting path (or the great
pallial development — c»» niially a mammalian feature. — Dc-
sctipiiuiis of some new spcci » of Australian Colcopiern, by
A. M. Lea. Desciiplions were given of lori) -nine species rom
New Souih W.des, m >stly belonging 10 the Aiilhiciilit. A re-
markable I'toiofialui trim the Tweed River was described, and

NO. 1312, VOL. 51]

a species of /,<j;'r/ij living in ants' nests. — Description of a new
hopogoH from New South Wales, by R. T. Baker. The
Isopo^on described was obtained on the Murrunibo Ranges,
Goulliurn River. It differs from the N.S. W. /. aiiemonifjliiis
in having deeply-divided leaves on long petioles and a silky
hairy perianth ; from the West .■\uslrali:in /. lons^foliiis in its
longer and pinn.itely divided leaves, smaller cones and longer
perianth. — Synonymy of some Australian an'H Tasmanian niol-
lusca, by John Brazier. The synonymy of twelve species were
given with references and habiials. — Further observations upon
the anatomy of the integumentary structures in the muzzle of
Ornithorhynchiis, by Prof. J. T. Wilson and C. J. Martin. The
authors specially dealt with the details of structure of the
"push-rods" in the skin of the snout of the platypus, and offered
further confirmation of their views in opposition to a recent
criiicism of some of these by Prof. E. B. Poulton. — Description
of the external characters of a very young specimen of Ornith'
rhynchus, by Prof. J. T. Wilson.

BOOKS, PAMPHLETS, andSERIALS RECEIVED.

Books. — University Tutorial Series. Vol. i ; \ Tcxr-book of Sound : E.
Citcnpool (Clive). — Manual of Practical Morbid Anaiomy : Drs. Rolleston
and Kanihack (Camtirtd^e University Press>. -The liook of the Rose;
Rev. A. Foster-Melliar (Macmillan) — Aa lilemcntary Treatise on Theo-
retirai Mectianics, Part 3 ; Kinetics . Prof. A. Ziwet (Macm Ilan). — Natural
RiRhts: Prof. D. G. Rilchic (Sonnenschein) — Elcmcniary Qualitative
Chemical Analysis : Dr. F. (.lowes and J. B. C "leman (Churchill) — Pubbli-
cazioni delta Specola Vaticana, Vol. iv. (Torino. Artifiianclli). — A Few
Chapters in Astronomy : C. Kennedy (Tajrlor and Francis).

Pami'MLETs.— I In the Natural Immunity against Cholera, &c. : C. G.
t:umpcl(Wdliains and Noriiate).— t'-lliptical Orbits; H. Larkin (Unwin). —
Royal Gardens, Kcw, Hand-list of Trees and Shrubs gr.iwn in Arboretum,
Pan I : Polypctal.x- (Eyre and Spottiswoode).

Skrials.— Engineering Maca/ine. December (Tucker).— American
Journal of Science, December (New Haven). — Strand Macazine. Decem-
ber (Newnes). — Natural Hislory Transactions of Northumberland, &c.,
Vol. xi. Part 2 (Williams and Norgaie) — Verhandlungcn des- Nalurhis-
torischen Vereins der Preussischen Rheinlande, &■■., Einundfunfligster
Jahrgang, Sechste Folge. L. Jahrgang. Erstc H'ilfte (Bonn. Cohen).—
Medical Magazine, December (Strand).- ie Mon.le Mnderne, January
(Pans)— American Natura ist, December (Wesley).— Strand Musical
Magazine, No. i (Newnes).— Royal Natural History, Part 14 (Warne).

CONTENTS. PAGE

Sir Richard Owen 169

Electromagnetic Theory. By J. Swinburne . ... 171

Recent Psychology '73

Our Book Shelf:—

Giberne : " Radiant Suns " 174

Mt-yer and I'aikinson : " Album von Papi'ia-Typen " 174
" Farm \'erniin, 1 kipful and Harmful " 174

Letters to the Editor:—

The New Cypress of Nyasaland. — W. T. Thisclton-

Dyer, CM. G., F.R.S i75

The Kinetic Theory of Gases.— S. H. Burbury,

F.R.S. ; G H. Bryan , 175

Science and History.— Alfred H. Huth 176

Geometry in Schools.— Edward M. Langley . . . '

Lilienthal's Experiments in Flying. (/Iluslraled.) .

Peters — Denza-Ranyard

Notes

Our Astronomical Column : —

Secular Variations of the Interior Planets 183

Irregularities in Variable Slats '83

The Radchffe Catalogue '83

V Aslionomic '°3

On the Ubc of the Globe in the Study of Crystal,
lography. By J. Y. Buchanan, F R.S 1S4

The Uhc of Safety Explosives in Mines 1S4

The Upsala Meeting ol the International Meteoro-
logical Committee '83

Endowment for Scientific Research and Publics
tion. U. . . .

Scientific Serials

Societies and Academies ''i°

I Books, Pamphlets, and Serials Received 'n

176
'77
■79

"79

186
190

NA TURE

193.

THURSDAY, DECEMBER 27, 1S94.

A STANDARD TREATISE ON CHEMISTRY.
A Treatise on Cheiitistry. By Sir H. E. Roscoe, F.R.S.,
and C. Schorlemmer, F.R.S. Vol. I. "The Non-
Metallic Elements." New edition, completely revised
by Sir H. E. Roscoe, assisted Isy Drs. H. G. Colman
and A. Harden. Pp. xi. 888. (London : Macmillan
and Co., 1S94).

TO write a satisfactory review of this book is no easy
task. The word which shall e.xpress an appreci-
ation and a criticism does not come readily to one's pen.
Turning over the pages and reading the lucid descrip-
tions of preparations and properties of element after
element, and compound following compound, one is
depressed, and borne down by the burden of many facts
and much learning. But to this depression succeed the
pleasure and the sense of power that belong to the
gaining of knowledge, and the feeling of security that
remains with the man who has got down to fund imental
facts.

In the preface to the first edition of this " Treatise," the
authors said :

" It has been the aim of the authors ... to place
before the reader a fairly complete, and yet a clear and
succinct, statement of the facts of modern chemistry,
whilst at the same time entering so far into a discussion
of chemical theory as the size of the work and the pre-
sent transition state of the science permit."

In his preface to the present edition. Sir Henry Roscoe
says:

"In this new, completely revised and reprinted, edition
I have endeavoured to carry out the aims which were put
forward in the preceding preface seventeen years ago.'

The aim and scope of the work are made evident by
these extracts from the prefaces. There can be no doubt
that the authors succeed in giving " a fairly complete,
and yet a clear and succinct, statement of the facts of
modern chemistry." The descriptions of the properties
of elements and compounds are lucid, full, and accurate ;
where all the properties of a substance cannot be
described, the selection made is satisfactory, sometimes,
one may suppose a student to say, too satisfying. But
this even llow of excellent description does not inspire
with enthusiasm him who reads; it does not open up
glimpses of the unexplored regions ; it fails to stir the
emotions. The book is wanting in the charm that
accompanies the "twilight of dubiety."

It is difficult always to agree with the authors in their
estimate of the relative importance of chemical facts. The
most important fact of modern chemistry I take to be the
statement that "the properties of the elements and com-
pounds,and the compositions of compounds, vary periodi-
cally with the atomic weights of the elements." This
f.ict ought, I think, to be made the basis of every treatise
on descriptive chemistry ; because only by doing this
can the facts regarding individual substances appear in
right perspective. The great fact which we owe to the
genius of MendeU'cfi' will find expression in a later
volume of this "Treatise" (sec p. 53); but the student who
uses the book will then probably have arranged the intel-
NO. 131 3, VOL. 51]

lectual contents of his mind, so far as chemistry is con-
cerned, in many little parcels, each tied up separately,
and he will find much difficulty in untying the parcels,
arranging their contents afresh, and getting them all
within the compass of the one binding generalisation.

.-\s regards the statements of the properties of the
different non-metallic elements and their chief com-
pounds, no detailed appreciation is called for. Where
all is excellent, a general expression of praise is sufficient.
The chapters wherein are described hydrogen, fluorine,
oxygen, sulphur, nitrogen, and the other non-metals, and
the principal compounds which these element form by
combining with one another, contain all that student
of chemistry requires to know about these elements and
compounds, except the comparison and contrast — that is
to say, the classification — of the substances described
The student has presented to him, in this volume of
the " Treatise, " the material that is needed for acquiring a
real knowledge of the chemistry of the non-metallic
elements.

Some of the expressions, and the ways of putting
descriptive facts, might be improved, in my opinion.

" Hydrogen occurs almost solely in a state of com-
bination in nature" (p. 129).

" In a state of combination hydrogen occurs in water "
(p. 129).

'' Bromine does not occur in the free state in nature '
(p. 188).

Expressions like these seem to me to be survivals
from the alchemical times, when, to take an example,
nitric acid was looked on as water endowed with acidic
qualities, which could be removed or restored at pleasure,
and hence was called aqua for/is. Surely it is not
hydrogen that occurs "in a state of combination," but
compounds of hydrogen that occur in nature. Similarly
if bromine occurs at all it must be "in the free state,"
else it would not be bromine but something else. Each
compound of hydrogen, and each compound of bromine
is just as definitely a chemical individual as hydrogen, or
bromine, itself.

I do not think that the object of chemistry, namely
the study of the connexions between changes of
composition and changes of properties, is set forth with
sufficient clearness. The statement on pp. 51, 52, for
instance, that

" the science of chemistry has for its aim the experi-
mental examination of the elements and their com-
pounds, and the investigation of the laws of their com-
bination one with another,"

cannot be regarded as satisfactory. On the other hand,
the examples given of chemical action, in the pages
preceding that where the sentence just quoted occurs,
undoubtedly serve to keep before the student the
fundamental fact that change is the essential note of all
chemical occurrences.

The term density is sometimes applied to gases in a
wav that is confusing. For instance, on p. 160 the term
is applied to the relative density of chlorine, referred to
hydrogen as unity, and also referred to air as unity,
without an indication that the unit has been changed.

A feature of the book which is much to be commended
is the giving of the defi'nite experimental data from
which important conclusions are deduced. A good

K

•94

NATURE

[December 27, 1894

example of this is seen in the authors' treatment of the
eudiometric synthesis of water vpp. ;4.6-25o). The actual
details of an experiment are given, with the experiment-
ally determined data, and the conclusion to be drawn is
then stated. It is much to be regretted that the authors
do not quote the results obtained by Scott regarding the
volumes of hydrogen and oxygen which combine to form
water, but content themselves with the less recent, and
certainly less accurate, measurements made by Morley
(P- =50-

The authors would have done well to have fol-
lowed their own practice elsewhere, and to have given
moderately complete details of the methods, and the data,
whereby the atomic weight of each element has been de-
termined. In describing the electrolysis of dilute sul-
phuric acid solution (pp. 45, 129, 251), the authors might
have more clearly insisted on the fact that the electric cur-
rent is employed to set free hydrogen and oxygen froin
an aqueous solution of sulphuric acid, and that they had
not, following it is true almost every other text-book,
spoken of the phenomena as the electrolysis of water.

Chemical equations convey, at the best, only a small
portion of the information one wishes to have regarding
chemical occurrences : but, by the simple devices of using
three kinds of type, and adopting a symbol to represent
an aqueous solution of a substance, these equations may
be made to tell much more than is conveyed to the
reader by the equations used in this " Treatise.''

In the extract from their preface already quoted, the
authors say that they enter into "a discussion of chemical
theory so far as the size of the work and the transition
stale of the science permit." The subject-matter of
chemistry is so large, and the difficulties of bringing the
vast array of facts into a focus are so great, that the
science is likely to continue for a long time in a transi-
tion state, and the principles of chemistry to continue to
be, as they are at present, rather a number of somewhat
loosely attached hypotheses than an harmonious and
binding theory. Nevertheless, more unity might profit-
ably have been given to the chapter on the " General
Principles of the Science." Many portions of this
chapter are admirable ; the whole of it is characterised
by lucidity. The portions dealing with the laws of com-
bination and the Daltonian atomic theory are especially
excellent. Brief but very clear accounts are given of
the experimental methods for determining molecular
weights, including the methods which are based on
van't Hoff's extension to dilute solutions of the law of
Avogadro. In connexion with the molecular condition
of substances in solution, there is a deliciously airy note
(p. Ill) : " P'or the literature of this subject the volumes
of the Zcitschri/t Jiir Physikalischc Clicmie . . . may be
consulted." The student who proceeds, with a light heart,
to consult the journal in question will find he has his
work cut out for him.

The book, taken as a whole, is admirable. The sure
position that the earlier editions of the " Treatise " have
taken in chemical literature has shown how much the
work was wanted, and how cordially it has been welcomed
by chemists. It is sufficient to say that this, the first
volume of the revised edition, well maintains the repu-
tation of the original " Roscoe and Schorlemmer."

M. M. Patiison Muir.
NO. 1313, VOL. 51]

MAN-THE PRIMEVAL SAVAGE.
Man — the Primex'al Savage. By Worthington G

Smith. (London: Stanford, 1894.)
]\ r R. WORTHINGTON SMITH has devoted him-
•'■'J- self for many years to a study of the localities
near London where implements have been found, and
has described the various paheolithic floors with great
minuteness, and illustrated them with great artistic skill.
In this book he brings all his previous discoveries
together, and groups them round his last work at
Caddington, near Dunstable, on the borders of Hert-
fordshire and Bedfordshire. He has presented to us a
monograph on palx-olithic camping-places, rather than a
general treatise on Man, the Primeval Savage.

The pahtolithic floor at Caddington was buried under a
depth of clay, sand and gravel, amounting in some
places to thirteen feet from the surface. The strata
occur in the following order from the surface : (i) Con-
torted drift ; (2) reddish-brown clay, with implements
stained with red ochre ; (3) subangular gravel with
ochreous implements, slightly worn and battered ; (4)
white clay ; (5) gravel, with white unworn implements;
(6) reddish-brown clay with implements ; (7) clayey
gravel with implements ; (8) clayey brick-earth ; (9)
palKolithic floor resting on a clayey brick-earth similar
to that above it. .Vll these deposits form a thickness
about eight feet in this section, and belong to the
complicated series of superficial sand clays and gravels
grouped together by the Geological Survey as brick-
earth, and clay-with-rtints, and which are clearly proved
to be later than the boulder-clay of the district. The
interest chiefly centres in the pala-olithic floor No. 9,
resting upon a sun-cracked surface in some places, and
in others supporting heaps of flints carefully selected,
and evidently piled together for the purposes of imple-
ment-making. Around them lay worked flints by the
thousand. It is obvious that here we are on the track
of a pala;olithic camping-ground, and that the deposits
which now cover it up have been accumulated, the fine
clays by heavy rains on the margin of a stream or on
the borders of a lake, and the sands and gravels by the
natural drift of the soil downwards from a higher level.
The distribution also of the flint implements in the section,
prove that man inhabited the district while the strata
were being accumulated above the pakvolithic floor up
to No. 2 inclusive. As the mud accumulated on the old
floor, the hunters, attracted probably by the water close
at hand, visited the same spot from time to time, and
left their implements in 7, 6, and 5 of the section. These,
our author considers to be the same age as those of the
palx'olithic floor. The worn ochreous implements in Nos.
2 and 3, he relegates to a later time in the pala;olithic
age, and considers them to have drifted downwards from
a higher level into their present position. '' The water
must have drained elevations which have now vanished,
and thehilltops of the Dunstable district of the present
time must represent the valleys of the old lime." Cad-
dington is now on the water-parting between the sources
of the Lea and the V'er, and under present conditions
there is no higher grounJ from which these materials
could have been derived.

The worked flints on the paleolithic floor represent

December 27, 1894]

NA TURE

195

every stage of manufacture, from the unshaped block to
the finished hdche. There are the flint cores and the
flakes lying beside them, there are flint hammer-stones
and anvils, punches and scrapers, and other implements
broken in various stages of manufacture. Very few of
the latter are finished. They would, of course, be
carried off for use, as was the case with those of the
palaeolithic floor discovered some ten years ago, in the
brickpit at Crayford, by Mr. Flaxman Spurrell. Mr.
Smith, we may remark, has followed the e.xample of the
latter, in the infinite pains he has taken to build up the
original forms of the flint blocks from the broken im-
plements and splinters. It is clear that in this place we
have the workshop in the condition in which it was left
by the paleolithic hunter. The fact that no bones and
no charcoal have been discovered, shows that the palaeo-
lithic huts were some little distance away, and that this
spot was selected solely for the purpose of implement-
making.

The association of the ruder with the more finished
of the palaeolithic implements in this floor, as in the case
of many of the paktolithic caverns, proves that a., appeal
to rudeness of form as a test of age, is a wrong principle.
That man must have learnt first of all tjo make the
simpler before he made the more comple.x implements,
is so obvious, that it has never been disputed. The
ruder, however, were used side by side with the more
finished, and many of those forms which are taken to be
of pre-palasolithic age in the gravels of the Kentish
plateau are the necessary result of the working of the
flint block into the palaeolithic hdciie. We may remark,
further, that some of these are also found in the refuse-
heaps round the old flint-mines of Cissbury, and have
been made in the manufacture of neolithic implements.

In the introduction, Mr. Smith deals with the
general question of the relation of paleolithic man to
the glacial period, and concludes, rightly in our
opinion, that man inhabited south-eastern England after
the glacial period. We also agree with him in looking at
the pre-glacial or post-glacial age of man as merely of
local significance, because the glacial period is a purely
local phenomenon not marked in the warmer southern
lands, such as the Indian peninsula, which was inhabited
by the paleolithic hunter. We know of him in India
simply as living in the pleistocene age. He probably in-
vaded Kurope in the pre-glacial age, and lived in
the south while Britain lay buried under a mass of
glaciers, or was covered by a berg-laden sea. He is
post-glacial in the valley of the Thames. He is not
separated from our own times either by a wall of ice —
one of the ice periods of Prof. James (leikie— or by
the tumultuous waters of a vast deluge, such as
that recently put before us by -Sir Henry Howorth.
He is separated by a geographical revolution during
which the seaboard of north-western Europe, as we find
it now, came into being, and Britain became an island —
as well as by a change in our land from a continental to
an insular climate.

The author also touches the difficult problem of the
physique of primeval man, and he accepts the "type de
Canstadt" as the earliest pakeolithic race. This is,
however, founded on a human skull which M.
d'Acy has conclusively proved to have no claim to any
NO. I313, VOL. 51]

definite age. According to the evidence of the catalogue,
still preserved, of the pleistocene maminalia found at
Canstadt in 1700, it was not found along with them. Dr.
Reissel, who superintended the exploration for the Duke
of Wiirtemberg, wrote in 1701 that no human remains
were then found, " inter que tamen nulla humanis
possunt comparari.'' Some fifty years later Dr. Albrecht
Gessner, writing on the discovery, remarks that it is
strange that no human remains had been met with.
Both these were doctors to the Dukes of Wiirtemberg,
and can only be supposed to know a human skull when
they saw it. It was not until 1835 that the skull in
question was found by Dr. Jaeger, in the Museum at
Stuttgart, and assigned without proof of any kind to the
find made 135 years before. It is very unfortunate that
such faulty evidence as this should not only be accepted
by the authors of " Crania Ethnica," but also used for
the definition of the type " de la plus vieille des races
humaines." In the present unsatisfactory state of the
inquiry into the physique of paleolithic man, the only
safe course is to subject all the facts which have been
recorded to the most searching criticism, and to wait for
the further light which will come sooner or later from new
discoveries. In this small and well-illustrated mono-
graph, Mr. Smith has made our knowledge of the paleo-
lithic workshop more definite than it was before, and
has collected together a mass of information which will
be of great service to the archeologists of London.

W. Boyd Dawkins.

THE SEQUENCE OF STUDIES.
Physiology for Beginners. By Professor M. Foster,

M.A.,"m.D., F.R.S., and Lewis E. Shore, M.A., M.D.

(London: Macmillan and Co., 1S94.)
Outlines of Biology. By P. Chalmers Mitchell, M. A.,

F.Z.S. (London: Methuen and Co., 1894.)
Practical Methods iti Microscopy. By C. H. Clark

A.M. (Boston: Heath and Co., 1894.)

THE scientific precision and modernness of a book
of elementary physiology, written by Dr. Shore,
under the supervision of Prof Foster, is scarcely to be
called in question. This little volume is amply ill ustrated.
and written with clearness as well as exactness. The
authors are especially to be commended for laying stress
in their preface upon the necessity of a preliminary
acquaintance with Chemistry and Physics, and it is to
be regretted that they had not the courage to insist upon
this point. But here they are gravely open to criticism.
" Knowing," they say, " how frequently a book on
physiology is taken up without any such previous ac-
quaintance, we have given a few chemical and physical
facts as preliminaries in chapter i." A few, and quite
too few, it is — six complete pages — expanding scarcely
any of the principles which are involved in the simplest
physiological explanation, giving, of course, no concep-
tions of the relations of chemical combination to energy,
nor of osmose, diffusion, solution, isomerism, nor the
action of ferments, all of which come to the front directly
one approaches respiration or digestion. We cannot but
think that this concession to a common educational
error is greatly to be deplored. The authors occupy a
I position of authority, and it was their privilege— a privi-

196

NATURE

[December 27, 1S94

lege they have neglected — to demand here, by assuming a
sound basis of chemical and physical knowledge, the
proper sequence of studies. As it is they have produced
a little primer that by virtue of its clearness and attrac-
tiveness and the prestige of their names, will serve to
uphold for a fe«- years longer a fundamentally faulty
system of scientific education.

The evil of a neglect of the rational sequence of studies
becomes particularly apparent in the chapters upon theeye
and ear. In the former of these an attempt is made to
convey all the optical principles involved, in seven lines —
'•convex lens" is not even defined^and in the latter comes
a series of dogmatic statements about sounds and noises,
without a particle of that progressive reasoning process
which is the very essence of genuine scientific study.
Once the initial concession svas made, however, this kind
of thing was an inevitable consequence. In order to
explain the science in hand, three or four others have to
be compressed to the limits of a paragraph.

The same unfortunate disposition to begin the wrong
way about is apparent in the little book by Mr. Chalmers
Mitchell. But in his case there is even less excuse. His
book is designed to prepare students for the Conjoint
Boards E.xamination, and therein he is an examiner.
Since he calls the tune he might have danced as he liked,
and he has, we conclude, preferred of his own free will
to contravene the common-places of educational science.
We find such a proposition as the following, printed in
spaced type ; so that the medical student, preparing for
examination by Mr. Chalmers Mitchell, who fails to learn
it by heart will have only himself to blame for his failure.
The earthworm, we are told,

" has reached the second stage of coelomate develop-
ment in that it is very highly segmented, and there is
little or no trace of the third stage, the stage of the con-
densation of segments." ..." V'ertebrates are highly
segmented animals, in which condensation of segments
has become an important factor, resulting notably in the
formation of a complicated head, and of kidneys formed
by the aggregation of many nephridia."

Now these propositions are illustrated rather than sup-
ported by a brief description of the anatomy of the earth-
worm, dogfish, and frog, and we find that even in the
case of these types the metameric segmentation of the
cranial nerves is scarcely alluded to, and the homology
of the mandibular arch with the branchial bars is not
presented as a probability, but stated as a fact. .Vnd, in
brief, .Mr. Chalmers .Mitchell, who is not a crammer, but
a teacher, gives the medical student the impression
almost in so many words — " cut and dried " and ready to
be cast into the oven — that the vertebrate type is merely
a concentrated derivative (concertina fashion) of the
chxtopod type, advancing this pure, and as he gives it,
baseless, speculation, in the face of the absence of any
ch.x'topod stage in the embryology or paleontology of the
vertebrates, in the face of the lesser metamerism in the
vertebral column of more primitive fishes, and in the face
of the declared opinion of many prominent anatomists.
Hut whether the view he gives is right or wrong is, from
our point of view, the smaller issue ; the great and grave
objection is the unscientific spirit of the presentation, the
narrowness bf the base of anatomical fact upon which
this far-rcachmg generalisation is raised. \Vc find this

NO. 1313. VOL. 51]

disposition to what is really the old theological trick of
dogmatism, again and again in his book, and it is the
evident and necessary consequence of an attempt ta
touch the far-reaching theories of comparative anatomy
without a sufficient preliminary study of individual types.
It is odd that we should find another aspect of the same
mistake cropping up in one chapter of Mr. Clar'-^'s ex-
tremely useful and well-arranged handbook for the
beginner in microscopy. It is in almost every way a
well-arranged and well-written work, and will be par-
ticularly a boon to the amateur to whom experienced
advice is inaccessible. But before proceeding to the
petrographical instrument, Mr. Clark has attempted a
"concise description" of polarised light, which begins —

"The elasticity of the ether in space is believed to be
equal in all directions. The same is true of the ether in
non-crystalline substances and in crystalline substances
of the cubical system. The particles of ether are con-
sequently free to vibrate equally in all directions. In
other crystalline substances the elasticity of the ether is
modified by the crystalline structure. In some crystals
there is one axis or direction about which the molecules
are arranged in a uniform manner ; such crystals are
said to be uniaxial. In other crystals there are two such
axes."

Now we believe a student who will clearly understand
this will be sufhciently advanced not to require it, and
that to the raw beginner, this passage, and its context,
will be incomprehensible. Were it not for the actual
evidence of these books it would seem the most unneces-
sary thing in the world to assert that a clear working
idea of the theory of polarised light, or the general
ideas of chemistry and physics, or a cyclopxdia of the-
anatomy of the metazoa, cannot be imparted in half
a dozen pages or so of text. If it could, our text-
books in these subjects would be unnecessary, for the
ultimate aim of all intelligent research and teaching in
pure science is broader and simpler general notions, and
there can be no need for a volume if a handbill will
sutlice. Cannot the scientific writer insist upon the-
proper sequence of studies in his preface, and proceed
on the assumption that his counsel will be observed .' To-
positively encourage students to proceed to subjects for
which they have not the necessary grounding, to proffer
them snap-shot chapters upon these neglected pre-
liminaries, is really, we are persuaded, to place a grave-
impediment in their way to genuine knowledge, all the
graver because it seems a help, and to place one also in
the way of our advance towards more efiicient science-
teaching in the future. H. G. Wei.LS.

OUR BOOK SHELF

Climbing and Exploration in the Karakoram- Himalayas.
By William Martin Conway, .M.A., F.S.A., &c. Con-
taining ijcientitic Reports. (London: T. Kisher Unwin,
1894.)
This supplementary volume contains reports on the
scientific results of .Mr. Conway's adventurous journey,
with his map of the mountain region between Kakipushi
and Golden Throne, through which he travelled. The
author supplies a list of measured altiludrs and notes on
the map, mentioning the differences from that of the
Triyononietrical .Survey of India. Lieut. -Colonel A. C.
Durand describes the ethnology and later history of the

December 27, 1894J

NA TURE

197

Kastern Hindu Rush, giving a brief sketch of the physio-
graphy of the region. Prof. T. G. Bonney and Miss C.
A. Raisin furnish notes on the rocks collected by Mr.
Conway, from which it appears that the majority much
resemble those of the Alps. The most interesting
. pecimens are a peculiar schist with secondary mica, a
piedmontite-schist, and a fragment allied to pseudo-jade.
Mr. \V. F. Kirby identifies the butterflies, Dr. A. (i.
Butler the moths, and Mr. \V. B. Hemsley the plants.
Df the last about a dozen were obtained at or o%-er 16,000
feet. The well-known Saxifraga oppositijolia was
gathered at 17,000 feet, and another species (the highest
habitat) at 17,320 feet. Mr, \V. L. H. Duckworth writes
on two skulls brought from Nagyr, and Prof. C. Roy dis-
cusses Mr. Conway's notes on mountain sickness, coming
to the conclusion that the primary cause of it is asphyxia.
Mr. Conway's observations agree with those of other
experienced climbers, that a man in good condition begins
to feel the effect of increased altitude at about 16,500 feet.
The fact that he is sensible of more inconvenience when
in a hollow among the peaks than when on an exposed
ridge, Prof. Roy attributes to some loss of oxygen by the air
when it has passed over a considerable tract of melting
snow. Mr. Conway has made valuable additions to our
knowledge of the geography and physical history of this
remote mountain region, and the present volume supple-
ments the more popular account of his travels, which
appeared earlier in the year.

The Royal Natural History. Edited by Richard
Lydekker, B.A., F.R.S. Vols. i. and ii. (London:
Frederick VVarne and Co., 1S93-94. )

Ar.ouT twelve months ago (Nature, vol. xlix. p. 220), in
a short notice of the two first parts of this work, we
heartily recommended it as worthy of the notice of our
readers. On a careful perusal of the two volumes now
before us, which equal one-third of the projected series,
we still feel quite justified in our recommendation;
the illustrations are for the most part extremely good,
and the text is not only interesting, but it is also intelli-
gently written.

The first of these volumes treats, in fifteen chapters,
of the Primates, the Chiroptera, the Insectivora, and the
Carnivora, as far as the dogs. We would especially
notice the chapters on the cats and the dogs, as having
information well up to date. Instead of the olten-quoted
old stones, it is refreshing to meet with accounts of the
habits of these animals, taken from the writings of
V. Ball, Blandford, Guillemard, Hudson, and Sterndale.
Thus, in the account of the common Indian mungoose,
we hnd mention of the results, to within the last year or
two, of Mr. Espent's experiments of introducing this
little carnivore to Jamaica. The sugar-planting industry
in this island was threatened with destruction on account
of the swarms of rats ; within three or four years after the
introduction of the mungoose the rat plague came to an
end, and the beneficial results to the island exceeded
^150,000 a year. Volume ii. commencing with the
bears, finishes the Carnivora, and describes the hoofed
mammals. The illustrations play so important a part in
these volumes, that we would suggest that the compara-
tive sizes of the figures should always be given, and when
possible the reader should be told where the figures first
appeared.

Kitchen Boiler Explosions. By R. D. Munro. Pp. 44,
(London : Charles Griffin and Co., 1895.)

The time having again arrived when domestic boilers
will be a source of trouble to paterfamilias, Mr. Munro
comes forward with an account of a series of ex-
periments with red-hot kitchen boilers, apparently re-
printed from the Transactions of some Society. Whether
this be so or not we do not wish to inquire, but to us it
seems that the diagrams of steam-pressure are little
NO. 1313. VOL. 5 1]

suited to the " intelligent householder" for whose edifi-
cation they are intended. The chief conclusions drawn from
the experiments are that (l) a dead-weight safety-valve
should be fitted to every boiler ; (2) water will flow into a
red-hot boiler although there is no free outlet, and, also,
that a steam-pressure can be attained in such circum-
stances sufficient to cause rupture of the strongest boilers
in use ; (3) whilst a very high steam-pressure may be
generated in a red-hot boiler by the sudden injection of
cold water, a disastrous explosion cannot thus be pro-
duced; (4) an explosion, in the true sense of the word,
cannot occur unless the boiler contains water as well as
steam. Probably the perusal of Mr. Munro's book will
help to diminish the disasters from boiler explosions.

The Island of Aladeira, for the Invalid and Naturalist.
By Surgeon-General C. A. Gordon, M.D., C.B. Pp.
no. (London : Baillicre, Tindall, and Cox, 1894.)

Persons who are fortunate enough to be able to leave
England during the dreary months of winter, and who
select to sojourn in Madeira — " The Flower of the Ocean "
— should take this brochure with them. The character-
istics of the people and the place are concisely stated, and
there is more information on the geology, meteorology,
zoology, and botany of the island than is usually given
in guide-books of a similar kind. It is well known that
Madeira has an extensive fauna and flora, and we agree
with the author that it is a matter of regret that the
island has no public museum where they could be collected
and investigated. Prof. Smitz, however, is gradually
forming such an institution at the college in Funchal.

LETTERS TO THE EDITOR.

[ The Editor does not hold himself responsible for opinions ex-
pressed by his correspondents. N, it her can he undertake
to return, or to correspond with the 'Writers of, rejected
manuscripts intended for this or any other part of NatiJRE.
No notice is taken of anonymous communications.]

" Acquired Characters."

Now that the correspondence on this subject, which you
all )wed me to start in your number of Nuvemlier i, seems
drawing towards a close, I ask leave through you to ihank your
correspondents for their courtesy in replying to my inquiries,
and also to make a few observations by way, so far as I am con-
cerned, of conclusion.

As none of your correspondents has found any fault with the
conditions which I suggested as essential to a good definition,
1 conceive that I may assume them to be correct.

Furthermore, as none of these writers has adopted or defended
any of the definitions which Weismann appeared to me lo give
or 10 sujigest, or ha^i said anything hy way of criticism on my
strictures on these dtfinilions, I think that I may conclude that
I was not far wrong in those strictures, and that WVismann's
writings do not aiTord any good definition of the words to which
he has given currency.

Mr. I'oulion has suggested that a definition may be found in
the statement that "whenever an organism reacts under an
external force, that part of the reaction which is diiectly due to
the force is an acquired character." But surely this is difficult
of application : for in every case of a reacliim on an external
stimulus there are twoelements — viz. first, ihe internal capacity to
respond, and secondly, the external force or stimulus. Each of
these is necessary lo the result and to every part of the result,
and neither is of it<elf sufficient to the re.-uli or to any part of
the result. How then can we analyse or break up the result or
the reaction into two parts, and say that the one is the direct
result of the external (ore ■, and the other is either not lis result
at all, or its indirect result? Where there is the j.nnt action of
two causes, each necessary hut neiiher sufficient of itself, I
conceive that you cannot either logically or pliysically sever
any part of the result from the action of tioth of llie causes, and
there is no ground for aiiriliuting directness to one part of the
the elTecl, and indirectness to another. Mr. I'oulion dwells
truly on the reaction having two causes — the internal and the

igJi

NA TURE

[December 27, 1894

external ; but this does not justify the analysis of their results
into two parts.

Nor does the matter become plainer to me when I follow Mr.
Poulion in his applic.ilion of his definition to concrete cases.
The 6r5t is the case of the so-called " Exercierknochen," a re-
action on an external force resulting in a certain number of
change* of tissue. How is it possible to classify those changes
into two categories — the one including changes directly due to
the external force, the other changesnot directly due to it? If
the stress is to be laid on the word "direct," then one must
respectfully ask what is its meaning ? how is it to be ascertained
and verified ? one must Inquire whether what is said to be
an indirect result, means anything but a result which is trans-
mitted? in which case we should find ourselves in a vicious
circle. I will not follow Mr. Poulton through the other in-
slancrs, but I believe the reader will find, like me, that each
raises similar difficulties, and that in no case does he analyse the
actual result into two distinct and separable parts.

Mr. Cilton proposes, and Prof. Ray Lankester adopts another
definiti'n, v'iz. " Characters are said to be acquired when they
are regularly found in those individuals only who have been
subjected to certain special and abnormal conditions." Now I
suppose that characters can be found regularly only either (l) in
individuals exposed to conditions which induce them, or (2) in
individuals who have inherited them. To say, then, of a
characier that it appears only regularly in individuals exposed
10 certain conditions, is to say that it does not appear in indi-
viduals by inheritance, and the proposition that acquired
characters are not transmissible is thus reduced to an identical
one. The possibility ol inheritance is excluded by the defini-
tion, and the inquiry whether acquired characters are inherited
i< impossible.

I do not propose to follow your learned correspondents into
many of the subjects touched on by them ; but the more their
letters are read, the more apparent does it become that they
are not at one, either with themselves or with Lamarck or Weis-
mann, as to the use of the words " acquired characters ; ' and for
myself, I repeat my regret that an inquiry of great moment should
he obscured, as I venture to think, tiy a premature use ofclassi-
ficalory words before the real classification of nature herself has
been ascertained. For the question, " Are acquired characters
transmissible?" I hope to see substituted the inquiry " What
characters are transmitted? " Ei)\v. Fry.

The alleged Absoluteness of Motions of Rotation.

All motion is relalive. This apparently universal state-
ment is a particular siatement about ihc meanings of words. The
word "motion" means "relative motion," or, more precisely,
"the motion of a body" means iis motion relalive to other
bodies. We may go further and make the still more funda-
mental statement that all position is relative^ or, in other words,
the position of a body means its position relative to olher bodies.
It is easy for anyone who puts words together without reflect-
ing sufficiently on their meaning to put together the noun
"motion" or "position" and the adjective "absolute," but
the expressions " absolute motion " and " absolute position "
are neverlhcless meaningless, just as much so as "white black-
ness," " retrograde progress," " the Action between a rough
body and a smooth body at their point of contact," or "the
potential energy of non-conservative forces."

The above remarks contain the .standpoint from which it is
concluded that motions of rotation are no more " absolute "
than motions of translation. Anyone who accepts them for
translation, but rejects Ihem for roialion, places himself in an
illogical position. Unless I have misunderstood them, this is
the posiMon "cciipied by Maxwell and Prof. Greenhill. The
slandp<in> ofih.-e » ho assert thai position and motion are in

all case.' reli' ' 1 to that of Newton, lie

held thaf th*f ' 1 immovable space, and rcla-

live poiition v,v., , . , .ind correspondingly ih' re

are absolu'r and rela ive motions; that absolute motion of a
body is its traruference from one absolute place to another absn-
lute place ; that we can never determine the absolute place o' a
body, l)Ui only iis relalive place ; that in c.Tses of rotation we can
dislingui'-h aluolulc from relative motion by the cffeds of
"centiilu^;al force." Me gives no indication how to distingiii h
absolute and relative motion* of trnnslati<in. From the im|>o«-
aibilily of determining ihe ahsidute position o( a body it seems
to follow that absolute mutiin of translation cannot be deter-
mined ; this view is adopted by Maxwell.

NO. 131 3. VOL. 5 I ]

Assuming that it is the object of the Science of Mechanics to
give as simple a description as possible of the observed facts
about the motions of bodies, the assumption at Ihe outset of
absolute motions or positions about which we can know nothing
appears an unnecessary complication.

From a logical point of view the cardinal statement in the
discussion is that all position is relative. It appears to be con-
ceded by Newton, and has been insisted upon by Maxwell, that
all knowable position is relative. To say that at any instant a
body has an alisolute position in space, but that we can never
know where it is except by reference to other bodies, that
is to say that every body has an absolute position, although we
can only know its relative position, is to introduce an unneces-
sary complic.Tlion, if it is not to talk nonsense.

What is done in practice is to determine the position of a
point by reference to a Cartesian system of axes, or by an
equivalent method. What is called " the velocity of a body"
is its velocity relative to the axes : what is called " the acceler-
ation o( a body" is its acceleration relative to the axes ; a body
has a motion of rotation when the angles between lines of the
body and any axis are changing with the time. It is part of the
solution of a mechanical problem, as presented by any set of
observed facts, to determine the system of axes with reference
to which the description of the observed motion becomes as
simple as possible, and there exists a calculus for transforming
the expression of a motion from one system of axes to another
when the relalive motion of the two systems is known.

The question how Ihe axes are to be determined has beei»
much discussed, but no general answer appears possible. Par-
ticular answers apply in particular cases. In general any three
points, not in a straight line, determine a set of coordinate
axes. For one of the points may be chosen as origin, the line
joining this point to another of the points may he chosen as one
coordinate axis, and the plane of the three points may bechisei>
as one coordinate plane. For the three points any identifiable
parts of bodies may he taken ; but, in general, axes so chosen
will be inconvenient, or, what comes to the same thing, the
description of a motion by reference to them will not be simple.

The description of motion is generally made in terms of the
concept force, that is to say, we stale the acceleration relative
to the .axes which a free body placed in a given position relative
10 the axes, and moving with a given velocity relative to the
axes would have, and the nature of the constr.ainis which give
rise to differences of acceleration in a constr.amed and a free
body moving through the same position with the same velocity
relalive to the axes. In an actual problem the acceleration of a
free body whose other circumstances (position and velocity rela-
tive to the axes) are known, must be found by experiment. It
does not concern the matter now under discussion that among
these circumstances posilion is generally predominant over
velocity in determining accelerations. What is of more import-
ance is the fact that the foi\e acting on a hotly Jepcniis on the
system of axes chosen. I'^or the force is a vector quantity whose
line of action coincides with the line of the acceleration relative
to ihe axes, and whose magnitude is proportional to this
.acceleration. This point has been noted by Maxwell. The
result that Ihe field of force depends partly on the axes is
frequently a guide to the choice of convenient axes of reference,
namely, we choose axes with respect to which Ihe expression of
the held of force is simple, and it oden happens that in this way
all motional forces, other than friclional resistances, can be
made to disappear. .'Vn e.asy and striking example of the dif-
ferences introduced by changing the axes can be found by con-
sidering the motion of two particles which move in one of the
planes chosen as coordinate planes with uniform velocities in
different lines relative to the coordinate axes. If a nevy set of
axes is constructed by taking one of the ))articles as origin, and
the line joining the particles as one axis, the .acceleration of Ihe
olher panicle relative to the new axes is directed towards the
first particle, and varies inversely as Ihe cube of the distance
lielwecn the two particles. Another very interesting example
IS furnished by Foucault's pendulum, to be discussed presently.

These remarks will serve as a preparation for the way in which
we interpret, in accordance with tl'.e principle of the relativity
of motion, ihose experiences which have been held to favour
Ihe view thai molions of rotation .admit of absolute determina-
lion. The history of the discussion appears to show that little
would have been heard of this doctrine apart from Ihe desire lo
rxpluin lo a public unused to regard motion as relalive the
theory of the rotation of the earth. To one who h.as mastered

December 27, 1894]

NA TURE

199

the relativity of motion it is manifestly the same thing to say ( i)
that referred to axes fixed in the earth all the stars describe
circles every day about the polar axis, or (2) that referred to
axes fixed among the stars the earth rotates about its polar axis
■once a day. If any ground can be alleged for holding that one
of these statements is the simpler, that is a ground for a certain
•choice of axes, not for saying that one motion is "real" or
"absolute," and the other "relative" or "apparent."

All the so-called "proofs of the earth's rotation" are de-
ductions from particular experiences which show that other
motions besides the diurnal relative motions of the e.arth and
,tars are more simply expressed by referring to axes fixed among
the stars than by referring to axes fixed in the earth. They all
■depend on the specification of " the acceleration due to gravity"
near the earth's surface. The neighbourhood of the earth is a
field of force, and the magnitude and direction of the force at
any point depend on the axes of reference. The specification
of the field of force is simplest when referred to thecenire of the
earth as origin, and to axes fixed in direction with reference to
the stars. The field is then expressed by the law of gravitation.

It is worth while to elucidate this matter in greater detail by
an examination of the most famous of these "proofs," that by
means of Foucault's pendulum. What is observed is that if the
pendulum is really free to swing about a point, and if the bob
alwayspassesabove the same pomtofa horizontal table (fixed with
reference to the earth) when at the lowest point of its swing, then
the plane of vibration turns slowly round, so that the line of
vibration is above now one, now another line drawn on the table,
the oscillation in the line being practically simple harmonic.
If this motion were referred to axes fixed with reference to the
table, there would be a component acceler.ition from the bob of
the pendulum towards the point of support (to be accounted for
by the constraint), a component acceleration in the plane of
vibration at right angles to the former (which we should
recognise as a component of gravity), and a component ac-
celeration perpendicular to the plane of vibration, and pro-
portional at any instant lo the velucity in the simple harmonic
motion. If we had nothing else to guide us, no observation of
the stars, no theory of gravitation, but knew only from less
refined observations that free bodies fall downwards with constant
acceleration, we should have to do two things : we should have
to try to simplify the specification of the acceleration of the bob
of the pendulum by referring to a new set of axes, and we
should have to conclude that our previous observations of falling
bodies had not disclosed all the facts about the field of force in
the neighbourhood of the earth. We should simplify the
specification of the observed accelerations by referring to axes
which (relative to the earth) rotate with the pl.-ine of vibration
of the pendulum, and we should conclude that such axes are re-
quired in order that the laws governing the motion of falling
bodies may be correctly formulated. What the experiment with
Foucault's pendulum really proves is not that the rotation of the
earth relative to the stars is an "absolute motion," but that the
system of axes, with reference to which the acceleration of a free
body near the earth's surface is of constant amount and directed
towards the earth's centre, is not fixed in the earth, but (relative
to axes fixed in the earth) these axes rotate with the stars.

It will be found on examination that every other so-called
" proof of the earth's rotation " is of the same character. By
each it is shown that the earth rotates in the same time and in
the same way relative to the axes required for the statement of
the law of gravitation as relative to the stars. It is not
legitimate to suppose that two relatives make one absolute.

It is true that the conclusion at which we have arrived takes
longer to state, and appears at first .'■ight less simple than the
statement by way of " absolute motion," but it contains no un-
defined terms, and no reference to anything assumed to exist,
but about which nothing can be known.

Objection has been taken to the attempt to express mechanical
theory in terms of relative motion, on the ground that it will be
perplexing lo beginners, and diflicult at any stage. In answer
to this it may be urged that in teaching beginners there is no
need to say anything about either relativity or absoluteness.
The motions that interest them are motions relative to the earth ;
the motions of boats, trains, cricket-balls, billiard-balls, and
machinery ; things that can be sufficiently described by reference
to lines fixed in the earth. It is only at a later stage when
general mechanical theories have to be studied, and a founda-
tion laid for physical astronomy and mathematical physics, that

is proper to insist on the relativity of motion ; and at this

NO. I3I3, VOL. 51]

stage it appears to me more important that our statements of
principles should be free from metaphysical obscuiity than that
they should be verbally short. A. E. H. Love.

The Antiquity of the "Finger-Print " Method.

.Sir William Herschel, in his letter to Nature (Nov.
22, p. 77), expresses his unbelief in the statement in the Nint-
ieenth Centitry (No. 211, p. 365), which ascribes to the Chinese
the original invenlion of the " finger-print" method of personal
identification. While I do not know upon what Mr. Spearman
has founded this statement, I have collected from a few sources
some facts which seem to justify the claim made on behalf of
the Chinese.

Although at present I have no record to refer to, it is a fact
that every Japanese, old enough lo have outlived the ancien
regime that passed away in 1869, well remembers the then cur-
rent usage of "stamping with the thumb" (Bo-in) on legal
papers, popularly called "nail-stamp" (Tsnme-in), on account
of the common use of a thumb with the edge of its nail in ink ;
whereas on papers of solemn contract, accompanied by written
oath, the "blood-stamp" (A't-//aH), or the stamp of the ring-
finger in blood drawn therefrom, was demanded.'

Chiirjo Katsuiakawa, the Japanese antiquary (1754-1S08),
writes on the subject as follows : " According to the ' Domestic
Law ') (Korei), 10 divorce the wife the husband must give her a
document stating which of the .Seven Reasons-' was assigned
for the action. . . . All [letters] must be in the husband's
handwriting, but in case he does not understand how to write,
he should sign with a finger-print. An ancient commentary on
this passage is : 'In case a husband cannot write, let him hire
another man to write the document . . . and after the husband's
name sign with his oivn index-finger." Perhaps this is the first
mention [in Japanese literature] of the ' finger-print ' method "
(i) This "Domestic Law "forms a part of the "Laws of
Taiho" enacted in 702 a.d. ; with some exceptions, the main
points of these " Laws" were borrowed and transplanted from
the Chinese " Laws of Yung-IIwui" {eirca 650-55 a.d.) (2) ;
so it appears that the Chinese of the 7th century a.d. had
already acquired the " finger-print"' method.

After the above-quoted passage, Katsurakawa continues
thus : " That the Chinese apply on divorce-papers the
stamps of the ends of the thumb and four fingers, which they
call ' Shau-miiying '{i.e. hand-pattern stamp) is mentioned
in ' Shwui-hii-chuen,' &c." (3). This " Shwui-hii-chueo" is
one of the most popular novels enjoyed by the modern
Chinese — so popular that I have met with many Chinese
labourers possessing it in the West Indies ; its heroes
flourished about 1160, and its author lived in the twelfth
or thirteenth century a.d. (4). As is usual with many
other examples, this novel gives us more accurate descriptions
of minor institutional features that co-existed with either the
heroes or the author, or both (5). .\fter making careful search
in this novel, I can now affirm that the Chinese in the twelfth or
thirteenth century used the finger-prints, not only in divorce, but
also in criminal cases. Thus the chapter narrating I. in Chung's
divorce of his wife, has this passage: "Then Lin Chung, after
his amanuensis had copied what he dictated, marked his sign-
character, and stamped his 'hand-pattern '" (6). /Vnd in an-
other place, giving details of Wu Sung's capture of the two
women, the murderers of his brother, we read : "He called
forth the two women ; compelled them both to ink and stamp
their fingers ; then called forth the neighbours ; made them
write down the names and stamp [with fingers] " (7).

It has been lately suggested by my friend, Mr. Teitaro
Nakamura, that possibly the "finger-stamp" was merely a
simplified form of the "hand-stamp," which latter method had
once been so current in [apan that it gave to the documents the
common names " Tegata" ((.c. hand-pattern) and " O.-hite "
{i.e. impressed hand)' (8). This view applies equally well to

1 '1 lie '■ tliumb-stump " w.is equally reg.'»rded witti the forni;il engraved
sea\(/iisii-:ii), but the "bioud-st.imp " had nuthing to do for ideutiticatiori.
For the formula of the latter mode of stamp, 7-iWe Ola, *' Ichivva Ichigen,"
new edition. Tokyo, iSSz. vol. xiii. p. 39.

- The Seven Reasons for divorcing the wife are ; (1) filial disol>edicnce ;
(2) banenness; (3) hcenttousDess ; (4)jealousy; (5) leprosy ;^(6) loquacity ;
(7) larceny.

•> It must not be presumed .is a fact that after the " fioger^stanip " was
introduced, it soon supplanted the " hand-stamp" : for even ill the seven-
teenth century the falter was sometimes used, as is instanced in the writ-
ing of Katn-Kiyomasa (1562-1611) preserved in a monastery near Tokyo.
C/. Kitamura, " Kiyii Shuran," new edition, 1SS2, vol. iv. p. 16.

200

NA TURE

[December 2;, 1894

the case of the Chinese, for they still use the name "hand-
pattern " for the 6nger-print (see above!. That this " hand-
stamp " was in use in an ancient kingdom of Southern India,
there is a proof in the Chinese records (9).

When we recognize that the hand-marks were early in use
for identification by the three distinct nations, the Japanese,
Chinese, and Indians, and when we consider that even the
teeih-marks were so commonly used for authentication in India
that the heir-apparent to As'oka RAIja did nDt hesitate in
plucking out his own eyes on recognizing the king's teeth-
mark that accompanied the false epistle (10), it would seem
quite true that among those ancient nations who were, with few
excepti>->ns, ignorant of the use of "written signature" method,
it was but a natural process that the methods were invented to
apply to identification some more or less unchanging members
of human body.

Further, that the Chinese have paid minute attention to
the finger furrows, is well attested by the classified illustra-
tions Kiven of them in the household " Td-tsih-tsii " — the
"Great Miscellany " of magic and divination — with the end of
foretelling the predestined and hence ttjuluuigiiig fortunes
(II) ; and as the art of chiromancy is alluded to in a political
essay written in the third century B.C. (12), we have reason to
suppo-e that the Chinese in such early times had already coit-
ceivtJ — if not perceived — the "for ever unchanging" furrows
on the fing'r-iips.

Bibliography. — (i) " Keirin Manroku," 1800, new edition,
1891, p. 17. (2) Y. Hagino, "Nihon Rekishi Hyurin," 1893.
vol. vi. pp. 2, 24. (3) Same as (1). (4) Takizawa, "Gendii
Hogen," 1818, vol. ii. chap. xli. (S) Cf. Davis, " China," vol.
ii. p. 162; Bazin, "Thciire Chinois," Introduction, p. li. (6)
Shi-rdi-ngan (?), " Shwui-hii-chuen," Kin's edition, Canton,
1S83, tOTii. xii. p. 4. (7) Iln<l., torn. xxx. p. 18. (S) Cf.
Terashima, " Wakan Sansai-dzue," 1713, torn. xv. an.
" Tf gata." (9) Twan Ching-Shih, " Yii-yang Tsah-tsu,' ninth
century a.d. tom. xiv. (10) lUuen tsang, " Si-yi'i-ki," sul).
"Takchas'ila"; Mirata, " Indo-zusbi, MSS. vol. xxi. pp. lo-ll.
26. (II) Terashima, «/.£■»■/. tom. vii. art. "Ninsomi." (12)
" Kan-fei-tze," lorn. xvii. sub. " Kweishi."

KUMAGUSU MiNAKATA.
15 Blithfield Street, Kensington, W., December 18.

Peculiarities of Psychical Research.

May I enter an emphatic protest against the notion insinu-
ated boh by Mr. Wells and Prof. Karl Pearson, that " I'sychi-
cal Researchers " are a sort of sect engaged in spiritualistic or
other propaganda? Most people, I am afraid, fight shy of
psychical resrarch, either because they are afraid that // there
is anything in it it is the devil, or because they have a scien-
tific reputation which they are afraid of losing. I do not know
to which category Mr. Wells belongs, but apparently he fails 10
understand that in order to make out a case against psychical
research he has got to show, not that the existence of telepathy
and clairvoyance has not been proved, but that there is not even
a /Wma/aciVcase worth investigating. When we remember that
ten years ago " mesmerism 'was included along with telepathy
and clairvoyance, we shall not attach much importance to .such
efform in siific inquiry. Even if the result should be to confirm
Mr. Wells's anticipation, and show that all the coincidences that
have been reported can be explaineil away as mistakes or mis-
statements, the inquiry will yet have been worth the labour
bestowed on it, if only as affording a measure of the value of
tetlimony to the miraculous. And if this comes to pass, the
bigots of science will lie ready enough to claim a share in the
work, if only by saying, " I told you so I "

I do not know what Prof. Karl Pearson means by his quite
gratuitous attack on " the scientific acumen of the psychical
researchefj." Surely he cannot imagine that ihcy overlooked
the point which he h.is unearthed ? The instructions to the
experimenters were, that "the agent should draw a card at
random, and cut the pack between each draw " (" Phantasms of
the Living." vol. i. p. 33. fool-nole) Could an abnormal dis-
tribution of Ihc card-i affect the result if those precautions
were taken, or ha» the Professor any reason to suppose the
instructions were not carrieil out ? EijWARI) T. DiXON.

Cambridge, December 14.

The following are a few of my grounds for questioning
the scientific acumen of the psychical researchers: — (i) M.
Richet's experiments are cited as if they were significant of
telepathic action. On the contrary, they give odds of so little
weight that they are significant of nothing but want of acumen.
I have in card drawing, tossing and lottery experiments, all
conducted with every precaution to secure a random distribu-
tion, obtained results against which the odds were move con-
siderable. (2) Mr. Dixon is unable to see the importance of
ascertaining whether there was an abnormal distribution in the
cards cut or the cards guessed. His inability is a strong con-
firmation of my standpoint. (3) I have heard lectures, and read
papers written by psychical researchers. Both alike seem to me
akin to those products of circle squarers and parado.\ers, with
which, as a reviewer, I am painfully familiar. As a concrete
example, I take my friend Dr. Oliver Lodge's psychical
papers. They are typical, to my mind, of the manner in which-
the scientific acumen of even a professed and most highly
competent man of science vanishes when he enters this field of
" research. "

I do not intend to take part in a controversy on the subject at
the present time, but I do suggest that no better exercise could
be found for a strictly logical mind with plenty of leisure than
a criticism of the products of the chief psychical researchers.
Such a criticism would be of much social value, in the light of
recent attempts to popularise the " results ' reached by these
investigators. Karl Pearson.

University College, London, W.C. December 19.

The Artificial Spectrum Top.

1 HAVE read with interest Prof. Liveing's theory of my arti-
ficial spectrum top as summarised in Katijrf. of Dec. 13, p. 167,
and am sorry I did not know of his conclusions before he made
them public, because a very simple experiment would, I think,
have convinced him of their inaccuracy. If Prof. Liveing, or
any of your readers, will examine my top rotated in the light of
a bright sodium flame, they will find that the colours are quite
distinct. I knpw of no other w,ay of seeing blue and red by
the light of sodium, and the phenomenon, I think, shows
decisively that the colours of the top iire "artificial " sensations
in the sense explained in my theory of the instrument.

December 10. Charles E. Benham.

I HAVE examined Mr. Benham 's top by the light of a bright
sodium llame, but have failed 10 see anything like the colours
which 1 see by daylight or by the light of an incandescent
electric lamp. By the sodium light the outmost three circles
appear, when the rotation is one w.iy, to he d.nrk brown, the
inmost three dark leaden grey, while the intermediate circles
are paler brown. Reversing the direction of rotation inter-
changes the appear.inces of the outmost and inmost three circles.
I cannot sec any red or blue, or green, in any case. Other
people here seem to see much the same as I do when the top is
illuminated by the sodium ilame only. With certain bh-ick and
while figures of my own, I can get a pink appearance in the
sodium light, but no green or blue. With spiral figures, which
are worrying to look at, I find that some i>eoplc can see a play
of colour even with the sodium light, but I do not see it myself.
Using a turn-table, by which the.rate of rot.ilion can be regu-
lated at will, I have found that the speed, in white light,
required to bring out the colours is decidedly diflferent for
dillerenl people. This fact convinced me that the explanation
of these very curious appearances must be looked for in some
physiological cause. It is perhaps worth remark that a sodiunv
llame, when there is much so<lium in it to make it bright, is by
no means monochromatic, though sufTicientiy so to make the
experiment with the lop a very interesting one ; and as Mr.
Itenham sees colours by this light which some others fail to see, it
goes far to prove the phenomenon to be subjective.

Cambridge, December 10. C D. LlVF.ING.

NO. I3I3. VOL. 51]

"Solute."

CiiRRESl'ONDlNG to the words " solvent " and " solution,"
some word is very badly wanted to express " the dissolved sub-
stance." The analogous word is cvidcnily " solute," and it is
as short and euphonious as the others. .May I inquire why it-is
not in general use? Surely some one must have proposed it ?

Leipzig. r. G. DoNNAN.

December 27, 1894]

NATURE

201

"The Elements of Quaternions."

In answer to my reviewer's question {zide p. 154), I must
rankly admit that

^a) Eq. S ->. 40, should have been a group of six equations,
■ = \ —I, y ^ V - I, &c. ; and that

{b) The inference should have been that /,/, &c., are (unequal)

(uare roots of negative unity. H. W. L. HiME.

THE LICK OBSERVATORY.

THE recent issue of volumes ii. and ill. of the
" Publications" of the Lick Observatory serves to
j;ive some indication of the growing activity of this world-
famed institution, and to foreshadow the great part
which it is destined to play in the astronomy of the future.
As in the case of so many other observatory publications,
these volumes contain much with which the various
astronomical journals have already made us familiar,
and one of their chief objects appears to be to collect
the observations into a convenient form for reference.

\'olume ii. is entire!)' devoted to the magnificent
micrometric work on stars and nebula: performed by Mr.
liurnham during his four years' connection with the
Observatory, which, to the general regret, terminated in
June 1892. It will be a matter of satisfaction to all
interested in the progress of astronomy to learn .hat this
keen-sighted astronomer has nothing but praise for the
great telescope. He says : " It has more than satisfied
the severest tests which could be applied, and the highest
expectations concerning its performance have been
realised. It is a monument of the genius and skill of
the unrivalled opticians, Alvan Clark and Sons, to whom
the progress of astronomical work all over the world is
so largely indebted." The fact that powers up to 2600
have been successfully employed, further emphasises the
excellence of the objective.

Mr. Burnham strongly insists upon the advantages to
be gained by the use of a micrometer in which the
wires are bright on a dark field. With this method of
illumination, he tells us, "any object that can be seen
under any circumstances, however faint, can be well and
accurately measured. There is no such thing as a star
too faint for measurement, if it can be seen at all."

Besides the immense number of numerical results, the
volume gives a mass of most interesting information
relating to the various objects observed. Some of this I
has already been published, but many new points have
been added. Thus, it appears that the observations of
^lOrionis show that " the six principal stars are absolutely
fixed with reference to each other, so far as any change
is concerned which could be detected by observations
covering more than half a century. ' The fulness of the
account of this remarkable group, and of the numerous
supposed discoveries of stars within the trapezium, furnish
an excellent example of the thoroughness which is so
characteristic of Mr. Burnham s work. With reference
to the very faint star discovered within the trapezium by
Mr. .Mvan E. Clark soon after the telescope was erected,
he writes : " It is a difficult object with the 36-inch, and
certainly has never been seen before, notwithstanding
the numerous alleged discoveries with telescopes down
to three or four inches aperture. Not less than a dozen
of these imaginary stars have been distributed about the
interior of the trapezium."

To the average astronomer, the star 95 Ceti would pro-
bably not be of absorbing interest, but to Mr. Burnham
it is " the most mysterious and strange double star in the
heavens." The companion was discovered by Clark
with a 7?. inch, was subsequently measured by Dawes
in 1854, and by Burnham with some difficulty in 1SS8,
since when he has not been able to see it even with the
36-inch.

Mr. Burnham finds that " none of the stars which
have been supposed from spectroscopic observations to be

NO. 13 13. VOL. 51]

close doubles, have shown any evidence of the fact when
examined with the large telescope under the most favour-
able conditions." He then goes on to say that " it is
possible some other explanation will be found for the
recurrent phenomenon first discovered by Miss Maury in
the Harvard spectrum photographs. At all events, it is
hardly worth while, until the method has been verified
upon some of the numerous known pairs suitable
for this purpose, to consume the valuable time of the
great telescope in a further examination of objects of this
class." One would almost imagine that Mr. Burnham
had failed to grasp the fact that the separation of the
component stars in such cases, by the spectroscopic
method, is solely due to their relative velocity, which in
ordinary pairs is relatively small. At any rate, it has
been estimated that a telescope of sufficient dividing
power to separate the components of /ij Aurigae must
have an aperture, not of three, but of eighty feet !

Limitations of space forbid further reference to the
rich feast which Mr. Burnham has provided ; the value
of much of his work will probably be only fully realised
by astronomers of another age, but at the same time a
large proportion of his results are of the greatest im-
mediate interest and value.

Vol. iii. of the "Publications" consists of Prof.
Weinek's now well-known selenographical studies ; a
report on specimens of glass similar to those used in the
construction of the great object-glass ; an investigation
of the glass scale of the measuring engine ; and Prof.
Keeler's observations of the spectra of nebulae.

It comes as a surprise to us to learn from Prof.
Holden's introduction to this volume, that the work of
the Lick Observatory is not without danger of suffering
for want of funds. Even so small a matter as a suitable
instantaneous shutter "could not be constructed until
the summer of 1893, for lack of funds and of skilled
workmen." In the early stages of the lunar photographic
studies, we are also informed that the work would have
been seriously interrupted had not the Smithsonian Insti-
tution come to the rescue with " several small appropria-
tions of money." The appearance of the present volume
has been made possible by the generosity of Mr. Walter
W. Law, of New York City, in providing funds to cover
the whole cost of producing the fifteen magnificent plates
of the moon which embellish its pages. They are
modestly described as " a gift to science," and they
afford another example of the practical sympathy with
astronomical inquiries displayed by so many of our
American cousins.

Few will be inclined to deny the great value of the
lunar photographs which have been taken at the Lick
Observatory, and it is a matter for congratulation that
the astronomical world has so soon been made acquainted
with the first fruits of their investigation.

Prof. Holden tells us that it was quite impossible to
undertake the investigation of the negatives at the Lick
Observatory, owing to the limited stafi", and they were
therefore placed freely at the disposal of Prof. Weinek,
" whose previous experience in lunar observations and in
photography, as well as his very unusual artistic skill,
made his advice and assistance of extreme value."

No pains have been spared to make the study of the
objects selected as complete as possible. As an instance
we may mention that Prof. Weinek's drawing of Coper-
nicus, enlarged twenty times from the negative, represents
the great labour of 224 ,' hours, and is described by Prof.
Holden as " a monument of skill and patience."

It is proposed that a complete map of the moon, on a
scale of 3 feet to the diameter, shall eventually be made,
though the practicability of making a map on four times
the scale is demonstrated by an enlargement of Tycho.
The photograph of the Lunar Apennines, on the 3-foot
scale, reproduced in Fig. i., is a magnificent example of
a camera enlargement from one of the negatives.

202

NATURE

[December 27, 1894

NO. 1313, VOL. 51]

December 27, 1894]

NATURE

201

Several points of great interest are touched upon by
Prof. Holden, among which is a brief discussion of the
dimensions of the smallest object on the moon which can
be registered on the photographic plate by the 3-foot
refractor. From this we learn that a crater on the
moon which is less than one-tenth of a mile in diameter
will form an image which is about the same size as the
grains of silver in the photographic film, and cannot in
general be distinguished. Craters not more than o'3 and
o'i5 English miles in diameter, however, have been de-
tected already. Prof. Holden concludes that for further
advances in lunar photography it will be necessary
to employ plates of greater sensitiveness so as to shorten
exposure, and also plates in which the grain is finer.
Workers in all departments of celestial photography have
felt the need of such improvements, and, as Prof.
Holden remarks, " future improvements depend more
upon the manufacturer of plates than upon the as-
tronomer who uses them."

Prof Weinek's concise descriptions of the lunar
formations figured in the volume, and his account of
the new features so far discovered, leave nothing to be
desired. Observers of the lunar surface may take con-
solation in the fact that even yet they are not in danger
of being entirely superseded by photographic methods,
for, as Prof Weinek points out, " both methods must be
perfected, and each must support the other." It is worth
remark here, however, that enlargements recently made
of lunar photographs taken at the Paris Observatory seem
to mark a clear step towards perfection. (See page 207.)

I'rof. Keeler's work on the spectra of nebula: during
his connection with the Lick Observatory, may fairly be
said to mark the commencement of a new era in the
history of the spectroscope as an instrument of precision.
The observations were undertaken in the first instance
at the suggestion of Dr. Huggins, who appealed to the
Lick astronomers in 1890 in connection with the discus-
sion as to the origin of the chief nebular line. It
uas found possible to use the third and fourth order
spectra of a grating spectroscope with advantage, and
even then the spectra were " by no means extremely
feeble." Former work left the wave-lengths of the
nebular lines uncertain to at least two tenth-metres, but
the uncertainties now amount to only a small fraction of
a tenth-metre. Further, it is claimed that the observa-
tions of the nebulae have shown the existence of errors in
.Xngstnim's scale and in the wave-lengths of the reference
lines, so that the observations did not become consistent
until more reliable reference wave-lengths were deter-
mined by Prof Rowland. As an example of the accuracy
ittainable, the velocity of Venus in the line of sight was
tciund to be 64 miles per second at a time when the com-
puted velocity was 7'69 miles.

It is not a part of our present purpose to discuss the
origin of the chief line in the spectrum of the ncbute,
but we may say that Prof. Keeler does not favour the
suggestion that it is due to magnesium ; but, on the other
hand, his measures definitely decide against the nitrogen
origin of the line.

After all corrections have been applied, the normal
positions of the first and second lines in the nebular spec-
trum are stated to be 5007-05 ± 0'03 and 495902 ± 004
respectively, and neither of the lines is represented
among the Fraunhofer lines which appear in Rowland's
photographic map. Indeed, we are not .-;ware that
either of these lines has ever been recorded as an
absorption line in the spectrum of any celestial body
whatever.

The observations have not been entirely limited to the
determination of the position of the chief line. It has
been found, for instance, that " the nebul.e are moving
in space with velocities of the same order as those of the
stars. Of the nebukr observed, that having the greatest

NO. 13 13, VOL. 51]

motion of approach, 40^2 miles per second, is G.C.
4373 ; that having the greatest motion of recession, 30'i
miles per second, is N.G.C. 6790. Most of the nebulse
have considerably smaller velocities than these."

It might well be imagined by anyone who has
seen a photograph of the Orion nebula that the dif-
ferent parts would have a relative movement with regard
to each other. .Such, however, does not appear to be the
case, according to Mr. Keeler ; or, at least, there is no
relative movement greater than four or five miles per
second. Attempts to measure the velocity of rotation of
the large planetary nebula G.C. 2102 showed that there
was no radial motion greater than eight miles per
second.

A study of the spectra of the nuclei of the planetary
nebuhe has led Prof. Keeler, as it has independently led
Prof. Pickering, to the conclusion that they are very
closely connected with the bright-line stars, and thus the
latest and most precise work goes to confirm one of
the fundamental points of Mr. Lockyer's meteoritic
hypothesis.

With reference to the discordant accounts of the
spectrum of G.C. 826, to which attention was drawn by
myself in 1S89 (Nature, vol. xli. p. 163), it is stated that
Dr. Huggins's observation of a continuous spectrum in
1864 "was evidently a mistake," the spectrum being of
the usual bright-line type.

Apparently in order to reconcile the presence of a con-
tinuous spectrum in such a nebula as that of Orion with
the idea that masses of rarefied gas were alone in question,
it has been suggested that this continuous spectrum may
really be a large number of adjacent bright lines. The
enormous dispersion employed by Prof. Keeler, however,
fails to resolve it into lines, and thus Prof. Tait's sug-
gestion as to the meteoritic constitution of nebute still
stands as the best explanation of the spectrum.

Many other points of interest are raised by Prof.
Keeler's admirable work, but sufficient has been said to
indicate the progress which has been made in this branch
of celestial physics and chemistry. Although Prof.
Keeler has now removed to the .Allegheny Observatory,
his successor at the Lick Observatory — Prof Campbell
— has already shown himself to be fully capable of main-
taining the spectroscopic department of the Observatory
at the same high standard of efificiency.

.\. Fowler.

STUDIES OF A GROWING ATOLL.

'TPHE researches of the surveying ships of the British
-l Navy have from time to time rendered services to
science no less important than those which it is their
function to perform for navigation. It has become an
established practice to encourage the surgeons of these
vessels to undertake scientific investigations in the

I leisure which their professional duties frequently
afford, and facilities are sometimes given for a com-

I petent man to continue such work by allowing his trans-

. ference to another vessel when his own has to leave the
place where he has been working. For this the Admiralty

( deserves credit and the thanks of those who desire to
see her Majesty's ships maintaining the position they

' took up in the days of Cook, and continued through
the voyage of the Beagle, and the long line of ex-

I peditions which followed it, to the voyage of the

! Challenger. While it may not be too much to hope for
a renewal of special marine research by the Royal Navy
before private enterprise reaps the waiting scientific
harvest of the unknown Antarctic, we feel that too much
prominence cannot be given to the good work done inci-
dentally in the course of routine surveys.

The hydrographer, Captain Wharton, in his preface to
the reports of Mr. Bassett-Smith on the .Macclesfield

204

NA TURE

[December 27, 1894

Bank,' expresses the general result of this piece of
research verj' clearly and concisely, showing that its
value is fully recognised by the' authorities at the
Admiralty.

The Macclesfield Bank is a shallow patch, rising
abruptly from deep water in the middle of the China
Sea, crossed by the parallel of i6 N. and frequently
passed by vessels. It is of an oval shape, about So miles
long and 30 wide, with a general depth of about 40
fathoms. Reports having been made of very shallow
water on the edge of this bank, forming a possible danger
to shipping, a complete sur\-ey was resolved upon, and as
preliminary soundings had shown indications of a raised
rim, instructions were given to pay special attention to
the animal life upon what might turn out to be an atoll
entirely beneath the surface of the sea. Half of the reef
was surveyed by Captain Moore in the Penguin in 1S92,
and collections made by means of dredges and divers,
under the superintendence of Mr. Bassett-Smith, several
tons of specimens being subsequently despatched to the
Natural Histor)- Museum for full study. The remainder
of the bank was examined in 1S93 by Captain Field in
the Egfri.i, to which ship Mr. Bassett-.Smith had ex-
changed in order to continue his work, and the result
is such an investigation into the biological conditions of
a submerged coral reef in mid-ocean as has never been
made before.

The whole circumference of the bank rises as a
ring of coral to within from 9 to 15 fathoms of the
surface, being broken here and there by wide gaps of
greater depth, but never so deep as the central depres-
sion, which varied generally from 40 to 4S fathoms. The
minimum depth on the rim was 6* fathoms, and an iso-
lated shoal rising from the centre of the inner depression
reached to within 5 fathoms of the surface.

The uniformity of the depth appears to Captain
"Wharton to be a strong argument against any move-
ment of the bottom since the period when the atoll form
was assumed ; and he shows that the simple growth of
coral on the rim will in time suffice to produce a perfect
ring-shaped coral island without the aid of subsidence or
upheaval. It appears, in fact, that here is an atoll in
course of formation on a foundation sufficiently near the
surface to allow coral to grow. Such a foundation
Darwin admitted might allow a coral island to form
without subsidence, and the recently discovered abun-
dance of similar elevations in the tropical oceans is one
of the main arguments for Murray's general theory of
coral growth.

Mr. Hassett-Smith's first day's dredging convinced
him that the Macclesfield Bank was by no means a
" drowned atoll," but on the contrary that it was very
much alive. The basis of the bank appeared certainly
to be dead coral-rock, or in many places a calcareous
rock composed of the consolidated vegetable organisms
which seemed most common between the depths of 20
and 50 fathoms. Upon this ground corals grew in
great patches, and other forms of life were very abundant,
especia\ly echinoderms, molluscs, crustaceans, and anne-
lids ; many very striking cases of mimetic resemblances
were observed amongst them. Altogether forty-one
genera of corals were dredged, excluding .alcyonarian
and hydroid corals : twenty-nine genera occurred between
25 and 35 fathoms, and tweniy-seven genera in deeper
water. It appears that reef-building corals can thrive at
depths as great as 50 fathoms in the conditions of the
Macclesfield Bank, where the water is very clear and
warm. Concerning the genera represented, Mr. Bassett-
Smith says : —

M..
A.
I-
P

Reporl on Ihe RcibIk of Drcdiinza obtained on the

in H M S r.lr •; '. r„m,,.,-„lr, \V IT. M..or.-, R.N.,

April
Her

NO. 1313. VOL. 51]

" The most universally distributed were Seriatopora,
Pavonia (especially a variety of forms very nearly allied
to Mycedium ekgans of Milne Edwards), Lcploscris
Montipora, and Styloplwr,^ Ciintheii, at all depths, but
the sections ' Madreporaria Fungida' and 'Perforata'
are undoubtedly most frequently met with in depths over
20 fathoms, and continued down to between 40 and 50
fathoms : the corallum being almost always light and
delicate. Agavicia, Phyllaslraa, Pacliyseris, Turbinaria,
and Liptoseris, in cups of varying size, from two inches to
twenty inches across ; Orypori, Pavonia, Hydrophora,
Scaphophytlia, and Montipora, in leaf-like expansions ;
Cyphastraa, Galaxca, Turbinaria and Montipora, in
encrusting growths ; or in branching forms, as Seria-
topora, Afussa, Madrepora, Psammocora, Napopora,
Anacropora, Alveopora, and Rhodarica ; the most
massive forms found in deep water being Pocillopora,
Stylophora and Mussa. On the sandy bottom of the
lagoon, and near the rim, the corals that seemed to
thrive best were small branching forms of Psammocora,
and Anacropora : delicate frond-bearing clumps of
Pavonia; Lcploscris cups, thick but light spreading
branches of Alveopora, Montipora ; and many simple
corals as Cycloseris, Fungia, &c. Small fragments of
more massive Astrcea were brought up three times from
deep water, twice from 30 to 40 tathoms, and once from
40 to 50 fathoms."

There was a strong current over the rim, even in calm
weather, and the surface water, the temperature of
which was sometimes as high as 88° F., swarmed with
Plankton.

In addition to the chart of the bank showing its un-
mistakable atoll form, the blue-book contains two
sections of the outer slope on a natural scale. The
angles varied somewhat on different sides. On the
north the slope was gradual, the 100 fathom line being
one mile distant from the 20-fathom line, while 200
fathoms was only found ten miles farther out, beyond
which the slope became more rapid to iioo fathoms six
miles beyond. On the east there was a much steeper
slope, the loo-fathom soundings being found half a mile
from the 20-fathom and 300 at the distance of a mile,
while fifteen miles away the depth was 2100 fathoms.
The wall-like spring of the bank from the ocean floor is
still more striking on the south, where depths of 150
fathoms occur half a mile from the edge of the bank, 30C5
fathoms at the distance of one mile, and. the oceanic
depth of 1100 fathoms, only 3J miles away, giving the
remarkably high average slope of i in 3. The shoal at
the north end of the future island is attributed to the
strong current from the south-west sweeping the debris
over the edge of the oceanic hill into the deep beyond.

The observations fully confirm Dr. Murray's preference
for the term " organic " rather than " coral " as applied
to the origin of atolls, for a very large part of the grow-
ing rock was shown to be due to calcareous alg.x, to
corals other than reef builders, and to the accumulation
of the calcareous remains of Crustacea, mollusca and
annelids. Mr. Bassett-Smith suggests that the crust of
alga: prevents the dissolved carbonic acid of the sea-water
from touching the dead coral rock below, while the
action of the growing alga; might decompose the
carbonic anhydride. This we are inclined to doubt, as
the decaying organisms would seem likely to produce
far more carbonic acid than could be disposed of by
the very feeble daylight which reaches depths approaching
40 fathoms ; and from the continual dredging of '' rotten
rock " in the central depression, we feel inclined to think
that active life and rock-growth are taking place there
only in restricted patches. The observations seem to
leave no doubt that the atoll is growing towards maturity
and the air, not declining from a past existence as an
island.

Huc.H Robert Mill.

December 27, 1894]

NA TURE

20:

NOTES.

Prof. George Forbes, F.R.S., who has for the last
three years been engaged on the utilisation of Niagara Falls,
has, we understand, just returned to this country from the
United States, the construction stage of the work being
now completed. The close of the three years of Prof. Forbes's
connection with the great work at Niagara Falls, which marks
the change from the period of design and construction to the
■period of commercial activity in the existence of the Niagara
■Falls Power Company, forms a fitting opportunity for express-
ing the sense of gratification that all Englishmen, and the
scientific world in particular, must feel in having had one of their

evolved a system which for completeness, adaptability, and
security against breakdowns, had not been dreamt of before.
The adoption of the alternating current before its value was
fully realised by others, the initiation of the world in the use of a
lower frequency than any that has hitherto been employed,
and the remarkable confirmation of the foresight as to the
economy of large transformers at high electric pressure, even
at the low frequency employed, that has been established, are
matters for congratulation. Although for fdller particulars of
the system and apparatus employed, we must refer our readers
to a previous account (Nature, vol. xlix. p. 4S2), we may
draw attention to the method by which Prof. Forbes met one of
the most troublesome questions in connection with the design of

Fig.

countrymen chosen to undertake the important and difHcult
liities of electrical consulting engineer to an undertaking of
uch magnitude. The manner in which those duties have been
discharged, and the pioneer services which Prof. Forbes has
rendered them in respect of the work, have, we are in
a position to say, received most gratifying testimony and
cordial acknowledgment from his Company, who recognise
in Prof. Forbes the scientific attainment, combined with
independence of thought and action, which have been
invaluable throughout the stage of operations now com-
pleted. Few realise the many novel conditions that have
had to be met at Niagara Falls. But by dint of years
of study of the many problems presented, Prof. Forbes has

NO .1313, VOL. 51]

the 5000-horse power generators (Fig. l), arising in consequence
of some requirements of the turbine designers — viz. the securing
of a certain necessary momentum of the revolving part of the
dynamo, without increasing the weight to be supported by the
hydraulic piston in the turbine above a certain limit. The diffi-
culty was met by fixing the armature, and revolving the field-
magnet, formed of a nickel steel ring with the oole-pieces pointing
radially inwards, outside, the ring, or yoke, and the pole-pieces
being supported by a bell-shaped cover fixed rigidly to the top
of the vertical shaft from the turbine, the shaft being supported
by bearings in the interior of the fixed armature. The fore-
seen ability to convert the alternating current into continuous
current, and the low frequency into high frequency, which is

206

NATURE

[December 27, 1894

now realised in the inTcntion of Messrs. Hulin and Leblanc,
gives greater elasticity to the system ; while the precautions
taken to avoid sudden opening or closing of the circuits, gives a
security against troubles experienced in the past by others such
as has not obtained before. The success that has attended Prof.
Forbes's effjrts during the period of design and construction is
of good augury for a successful issue to the commercial stage
which the Niagara Falls Power Company now enters upon.

Reuter reports that a violent earthquake shock, lasting one
minute, was felt at Oraviczi, South Hungary, at 10.35 P-™- on
December 19. Many houses fell in, while the walls of others
were seriously cracked.

A Bacteriological Institute is about to be established in
the University of Kie(r(says the British Medical yoiirnal), at
an estimated cost of ;^lo,ooo. A well-known druggist of
Moicow has also given a house, valued at £y>oo, with ;£^S00
towards the fiitinj^ up o( it as a bacteriological laboratory.

We regret to record the death, on the 19th inst., of Prof.
Allen Harker, of the Royal Agricultural College, Cirencester,
at the age of forty-six. Mr. Harker was a popular and success-
ful teacher, and did good work, not only at the College, but in
connection with County Council technical education schemes,
both in Glojcestershire and Bedfordshire.

The Italian Botanical Society has decided to hold its annual
meeting for 1895 in Palermo, in the latter part of April.

The influence of the Royal Gardens at Kew upon other
Botanic Gardens is strikingly shown in a list of the staffs of
botanical departments and establishments at home, and in
India and the Colonies, given in the AVii' BuUclin (.\ppendix
III.). Disciples have gone from Kew to the ends of the world
to become directors or curators of Botanic Gardens ; indeed,
almost every Garden seems to have on its staff someone trained
at Kew, or recommended by the Director there. A clearer
testimony of esteem could not be desired.

From Mr. Carruthers's Report of the Department of Botany
in the British Museum for 1893, we learn that the herbarium
received some valuable additions during that year by gift and
purchase. The most important were Mr. Deby's great
collection of diatoms, numbering nearly 30,000 named slides ;
the late Mr. Jenner's collection of over 6000 specimens of alga;,
a collection of over 1000 of the lower cryptoglms of Dominica
and St. Vincent, presented by the committee for the exploration
of the West Indies ; and a large number of flowering plants
from Malaya, presented by Mr. Ridley.

A RAPID fall of the barometer on Friday, the 21st inst., made
it clear that a serious disturbance was approaching our shores
from the Atlantic, and by 6 p.m. of that day a "fresh " gale
had already set in on the nonh-west coast of Ireland. Daring
the night the centre rapidly crossed Scotland, and the whole of
the United Kingdom experienced severe westerly gales, which
occasioned great loss of life and properly, and although the
storm ar-a (ubsequcntly crossed the North Sea, violent north-
westerly winds continued during the whole of Saturday. The
anemometer at (jreenwich on .Saturday morning showed a
pre«ure of 29 pounds on the square fool, which is equivalent to
a velocity of about 76 miles in the hour ; but considering that
the centre of the disturbance was at that time at least 400 miles
to the north, there is no doubt that considerably higher veloci-
liei occurred in other parts of the country. In .Scotland the
barometer fell more than an inch and a half in 24 hours, and
the subsequent rise was even more rapid.

Wk have received two numbers of Biology Notes, a monthly
pamphlet published by the Technical Instruction Committee of

NO. 13 I 3. VOL. 51]

the Essex County Council. Under the direction of Mr. Houston
'he problem of reconciling the practical reiiuirements of this
district with a really scientific method of instruction in biology
seems to be in rapid progress towards a satisfactory solution.
Pioneer lectures are given, short courses for farmers and gardeners
on such immediate topics as plant diseases, and systematic and
largely practical courses of study in botanical science, at the
Chelmsford Laboratory, and at various local centres. In addi-
tion, the Chelmsford Laboratory is rapidly becoming a centre
for inquiry into, and the discussion of, agricultural problems.
During the last three months the influence of ergot on gravid
cattle, the toxic eftect of bracken fronds, certain samples of
foreign hay that had caused disease, and the distribution o
potato disease, among other topics, have received attention. The
combination of elementary instruction in science, on the one
hand, with original inquiry on the other, and the practical
Simplicity of both depirtments of work, appear to us to be admir-
able features, and we would recommend it to the attention of
those who are interested in Technical Education in similar
districts in otherJparts[of the country.

Field experiments of an instructive kind are carried on al the
Royal Agricultural College, Cirencester, under the direction of
Prof. E. Kinch. A pamphlet just received conlainsjan account of
CNperiments on oats grown this year on twenty-four plots differ-
ently treated. The general results were as follows : — The smallest
yield of corn was from the plots receiving ammonium salts only,
the unmanured plots, .tnd the plots receiving cinereal manures
only. The highest yield of corn was from the plots receiving four
teen tons of farmyard manure every year since 1SS5, followed by
the plots receiving cinerealsand mineral nitrogen, and phosphates
and mineral nitrogen. The largest amount of s'raw was also given
by the plots which had received the larger amount of farmyard
manure annually, followed by tho;e receiving mineral nitrogen
with phosphates. The withholding of potash appeared to make
little or no difference in the yield of straw, but the withholding
of phosphates made a difference. The unmanured and cinereal
manured plots gave the least straw. Experiments were also
made to determine the crops of hay from twenty plots, to which
different kinds and quantities and manures had been applied.

The last issue of the Zcitschrift fiir Physiialisclie Cliemie
(vol. XV. part 3, p. 386) contains a paper by Messrs. Raoul
Pictet and Altschul on " Phosphorescence at very Low
Temperatures," which is of special interest in connection with
recent work on this phenomenon. Glass tubes containing the
sulphides of calcium, strontium, and barium were exposed to
sunlight, and the duration and the extent of the phosphor-
escence were noted. The various lubes, after having been ag.ain
exposed to sunlight, were plunged into liquid nitrous oxide, the
temperature of which, by rapid diminution of pressure, could be
brought to -140°. After twelve minutes' immersion the tubes
were brought into a dark room, iand their behaviour carefully
observed. Al first no indication of phosphorescence could be
seen. In a few moments the upper part of the tube, which had
not been so strongly cooled .as the rest, began to phosphoresce,
and gradually ihe feeble light seemed to spread itself down the
tube, the lower pari of which, however, glowed much more
feebly than the upper. .Vftcr five minutes the tubes acquired
their ordinary vivid colour, without subsequent exposure to sun-
light or even to diffused daylight. All phosphorescent sub-
stances appeared to behave in this way. I'urther experiments
were then made in order to determine the limits between which
these phenomena occurred. For this purpose a quantity of
alcohol was cooled to -80°, and in it a tube containing some
phosphorescent substance, after insolation, was immersed. That
portion of the tube which was surrounded by alcohol in the out-
set glowed feebly, but in proportion as it took up the tempera-

December 27, 1894J

NA rURE

207

ture of the cooled liquid its phosphorescence diminished,
until at -65° it entirely disappeared. The portion of the
tube above the alcohol continued to phosphoresce strongly.
After thirty minutes' immersion in the cooled alcohol, the
tube was removed, and as it gradually acquired the tempera-
ture of the air, the lower portion began to glow. Before the
glow — blue, green, or orange in colour, depending on the nature
of the metallic sulphide — entirely disappeared, the colour be-
came a faint yellow. It was found by comparative e.xperiments
that the alcohol exerted no specific influence on the results.
These seemed to be entirely dependent upon the diminution or
total cessation of molecular vibrations at the low temperature.

An interesting paper on the Sicilian earthquakes of last
August has recently been published by Dr. Mario liaratta (Boll,
della Soc. Geogr. Hal., Ott., 1894). The first shock of the series
was felt on July 29 at Randazzo, and was succeeded by several
other slight shocks, mostly in the Lipari Islands. Then came
the severe earthquake of August 7 at i2h. 5Sm. p.m., and the
still stronger one of August 8 at 5h. l6m. a.m. (Greenwich
mean time). These affeCeJ chiefly the south-eastern slope of
Etna, and were followed by more than twenty shocks in the
same district, lasting until August 26. The meizoseismal area of
the principal earthquake (August 8) is only about 7 km. long
and 3 to 4 km. broad, and, as the intensity diminished rapidly
outwards, it would seem that the focus cannot have been far
from the surface. Moreover, the longer axis of thi> area runs
north-west and south-east, and, when produced, passes through
the central crater of Etna It therefore probably coincides with
a radial fissure of the cone, and indeed is not far, if at all, dis-
tant from that along which the eruption of 1329 took place.
The pressure exerted by the column of lava in the central
funnel, or by the forces which have raised it to its present
height, may have caused such a fracture to be reopened. Thus,
it is not impossible that the recent earthquakes indicate an un-
successful attempt at a new lateral eruption.

Ft7RTHER details relating to the same earthquake; are given
in the Bollcttino MdeorUo (Suppl. 1 10) of the Geodynamic
OfiSce of Rome. The depth of the focus of the principal earth-
quake, according to Prof. Ricco, was about 4 km. The pulsa-
tions were recorded at Rome bythe great seismograph, consisting
of a pendulum 16 metr-is long, with a mass of 2co kg. ; the
first traces at Sh. 17m. 30;., and the principal maximum at
Sh. l8m. 55s. The puteometer of the Observatory of Catania
shows a .trace about 21. l mm. long, indicating a temporary
lowering of the well-water, which, in returning, stopped about
4 mm. below its original level.

The additions to the Zoological Society's Gardens during the
past week include a Yellow Baboon {Cynoccphalus babottin, 9 )
from Fort Salisbury, South Africa, presented by General 0*en
Williams ; two Grisons {Galiclis vitlala) from Brazil, presented
by Mr. H. A. Caflett ; a Song Thrush ( 7"H;-i/«j miisictis), a
Goldfinch ( Car(r'j«//.t elcgans), British, presented by Mr. B. M.
Smith; a Grenadier Weaver Bird {Eiiptcctts ory.x, i) from
West Africa, presented by Lady McKenna ; a Wild Cat
(Felis calm) from Scotland, deposited ; five Shore Larks
(Otocorys alpestris), British, purchased.

OUR ASTRONOMICAL COLUMN.

Advances in Ll-nar Photography. — MM. Lcewy and
Puiseux recently communicated to the P.iris Academy a paper
on photographs of the moon, t.iken at the Paris Observatory, by
means of the great Condc' equatorial. Some of the photographs
have been enlarged by Dr. Weinek, and the enlargements seem
to have excelled in beauty and detail previous lunar pictures of a
similar kind. .\n examination of the photographs shows that not

NO. 1313, VOL. 51]

only c.in they be used to verify the general feature5ofthem')->n'
surface, as depicted upon the most recent and complete lunar
maps, but they also show a number of details and small craters
which so far have been omitted from such maps. There are, of
course, a number of causes which prevent a single photograph
from being an ideal representation of a celestial object, and
enlargements are usually regarded with a certain amount of
suspicion, for there is always a possibility that interesting forma-
tions will be unconsciously manufactured in the process. MM.
I^cowy and Puiseux know this as well as anyone ; nevertheless,
they find that the enlargements undoubtedly reveal new features,
and definitely determine the existence of several contested
objects. They think an instrument of long focus is essential
for the best results, and that the enlargements should not be
carried beyond twenty or thirty diameters. One object upon
which the photographs have thrown light is the small isolated
crater Linnc, situated in the middle of the Sea of Senenity.
According to Shroeter, Beer, Maedler, Lohrmann, and other
selenographers, this crater was distinctly visible up 10 1866,
when Schmidt announced its disappearance. It was afterwards
discovered again, but was much smaller than when described
and figured by Beer and Maedler. Dr. Weinek finds that the ob-
ject appears upon a plate taken on March 14, but only one kilo-
metre in diameter — that is, about one-tenth the value assigned
to it by the earlier observers. The crater has also been found
on other plates, and Sig. Schiaparelli has testified to its reality.
Four new objects — three craters, and the fourth an isolated
elevation of some kind — have been found in the plain which
extends to the south of Ariadaeus, between the bright crater-
plain Cayley and the Silberschlag crater. Ten new craters can
be detected in the typical walled plain Albategnius. All the
rills observed to the west of Triesnecker can be seen to extend
beyond the limits previously assigned to them, and to con-
nect Ariadaeus, Hyginus, and Triesnecker with interlacing
clefts. Judging from these results, we cannot but conclude that
the photographs represent real advances in lunar photography.

CoMETARV Ephemerides.— The following ephemeris for
Encke's comet is in continuation of that given on November 22,
■and is due to Dr. O. Backlund. M. Schulhof's ephemeris, in
the Aslronomischc Naclirichten, No. 3267, is used for Swifi's
comet : —

En

cke's Come

Swift's

Comet.

Ephemeris for Berlin

Ephcmeri

for Paris

Midnight.

Midnight.

1894.

R..4.

(.-ipp.)

Dec), (app.)

R.A. (app )

Decl. (app.)

h

m. s.

. , //

h. m. s.

p . //

3ec. 28

... 22 1457

-3 35 "8

0 323 .

. . - 0 20 22

30

1427

3 1958

0 833 •

o'7 53

an. II

1352

3 338

013 41

•■ +05345

3

«3 9 ■ •

245 5'

1846 .

•■ I Zl 10

5

12 16

2 26 7

2349

2 10 9

7

II 8

2 3 47

28 51 .

24641

9

942

I 38 I

3350

■■ 32244

II

752 ...

I 7 53

3848 .

■ 35819

'3

S3I •••

-ho 32 10

43 43 •

• 4 33 24

■5

232

-0 1034

4837 •

580

17

2!

5847 .-

I 2 10

53 29 ■

5 42 5

19

54 3 -

2 442

5819 .

61542

21

48 10

3 2029

•3 8 .

. 6 48 48

23

4057

4 51 53

7 55 •

7 21 24

25

32 13

64045

12 41

• 7 53 29

27

21 57 ...

- 8 47 28

17 26 .

• 825 4

It will be seen from these ephemerides that the two comets
are in the same region of the sky, both being a few degrees
south of Pegasus. Observations of the comets are greatly needed.

Russian Astronomical OnsERV.\TioNs. -^ The latest
Bulletin (vol. XXXV. No. 4) of the Imperial Academy of Sciences
at St. Petersburg is almost entirely devoted to astronomical
papers. K. Lindemann contributes a discussion of the visual
and photographic magnitudes of Nova Auriga;, and gives a
light curve extending from December 10, 1891, to April 13,
1S92. N. Nyren discusses the observations made at Pulkov,^
with the vertical circle, between 1882 and 1891, from the point
of view of variations of latitude. The curves derived from ihe
observations indicate that the interval between two maxima is
433 d.iys. and between two minima, 434 days. .\s to ihe
amplitude of the variation, though no definitive result is
stated, the value of the radius of the circle described by the
instantaneous pole appears to be 0"'I45, and the direction of

2oS

NATURE

[December 27, 1894

motion from nest to east. Ano'.her paper on the sam e subject
is contributed to ihe BuIUUn by S. K^s'.insky. In this case,
tbe obierva'ions discu«ed were made with the greit meridian
iastrument of the Pullcova O >serva!or)', mounted in the prime
vertical. The period obtained was 411 days, and tli; amplitude
o "541. In addition to these patters, there is one on the orbits
of Bielid meteors, dedaced by M. Bredichia fron o bsetvations
made in 1892.

ON A REMARKABLE EARTHQUAKE DIS-
TURBANCE OBSERVED ATSTRASSBURG,
MCOLAIEW, AND BIRMINGHAM, ON
JUNE 3, 1S93.

Introductory Note.

'pHE Horizontal Pemiiilum. — The observations described in
the subjoined article were made with the horizontal
pendalam desij^ned by Prof. Zoilner, and modified by
Dr. von Rebeur-Paschwitz. This instrument consists
of three thin brass tubes jointed together in the form of
an isosceles triangle, the vertical angle of which is about
45'. The two equal sides are prolonged slightly beyond
the base, and to the ends are attached two small spherical agate
cups, the concavity of the lower one being directed from the
centre of gravity "f the pendulum, and that of the upper one
towards it. When the pendulum is placed in position, these
cups rest on two steel-points attached to the stand of the
instrument and directed normally to the surfaces of the agate
cups. One steel-point is almost exactly above the other, so
that the axis of rotation is nearly, but not quite, vertical, its
inclination to the vertical being still great compared with the
movements of the ground we wish to investigate. The
pendulum rests in the vertical plane passing through the axis
of rotation, and on the side towards which it inclines. If this
is towards the east, and if the axis is slightly tilted in the
east and west plane, there will be no deflection of the
pendulum ; the only change will be in its sensitiveness. But if
the axis is lilted in any other plane, it will no longer incline
towards the east, and the pendulum will be deflected from its
original position, in order to remain in the same vertical plane
with the axis of rotation. It is evident that the smaller the
original inclination of the axis to the vertical, the greater will
be the deflection for a given tilt of the axis in the north and south
plane ; that is, the greater will be the sensitiveness of the
pendulum.

From the middle of the nearly vertical tube of the pendulum,
there projects outwards a small bar. Passing through an
aperture in the frame to which the steel-points are attached,
this bar carries a mirror, whose plane is at right angles to that
of the pendulum. A ray of light, proceeding from a fixed source,
is reflected by the mirror, and registers the movements of the
pendulum on a strip of photographic paper wrapped round
a revolving drum. The zero-line is traced by a ray of light
reflected by a fixed mirror just below the other, and attached to
the stand of the instrument.'

Obsenation of Earlhijualu Pulsations. — Nothing could show
l)etler than Dr. von Rebeur-I'aschwitz's interesting paper how
desirable it would be to have a few well-chosen stations in
different parts of the world where these pulsations could be
registered. They might then be traced .is they spread out from
the origin of a great earthquake, and might even be followed,
as he suggests, in their course, completely round the world.

In several Italian observatories there are established instru-
ments suitable for this purpose. Horizontal pendulums, with
reording apparatus, are now at vtork at Charkow and Nicolaicw
in the south of Russia ; and two others will soon be ready at
Strassburg and Mcrseburg in Germany. A bifilar pendulum ■
at Birmingham, belonging to the British Association, will
shortly be furnished with a photographic recorder. Thus
Europe is at present fairly well provided for.

.\ large number of stations in other parts of the world is by
no means absolutely nccestary. Results of great value would
lie derived if recording instruments were erected at places near

t For A fu'l'-r ..• ^(iinl of iVi* tiori/.nlrit p'n<liil-im. \ft Dr. von Kcbeur-
P.n- (' r'a Acta Her kail.

/.. ', Bd. Ix. 1899,

PI' ' '

■' NATUi;!^ Uu'y 'J. 1-/4). vjI. ;'j, w- -4' 4/ . Urii. Assoc. R«p,, j8<)3,

pp. 29I.JO>

NO. 1313, VOL. 51]

the east aud west coasts of North America, in South .America,
South .\frica, India, Australia or New Zealand, and the Sand-
wich Islands. In Japan Prof. Milne's tromometer' leaves lit'le
to be desired.

The chief element to be determined is the exact epoch of
the beginning, maximum amplitude, and end of the
pulsations, or of each group of pulsations. The hori-
zontal pendulum. Dr. von Rebeur-Paschwitz informs me,
can be arranged so that its sensitiveness for slow tilts of
the ground can be diminished without necessarily lessening its
sensitiveness for earthquake shocks. The strip of photo-
graphic paper can thus be reduced in width without running
any risk of the spot of light leaving the paper during its
ordinary daily and other movements. Without increasing the
expense, a more rapid movement of the paper could be per-
mitteil, and this would enable the determination of the time to
be made with greater accuracy. Possibly, also, the construc-
tion of the instruments might be simplified if earthquake-
pulsations arc to be the principal subject of investigation. In
the bifilar pendulum, for example, since the amplitude of the
oscillations is a point of minor importance, the somewhat
elaborate machinery for determining the angular value of the
scale divisions might be dispensed with, and also the arrange-
ments for readjusting the spot of light from a distance.

Hardly less important in these investigations is the deter-
mination of the exact time of occurrence of the earthquake at or
near its centre of disturbance. But on this it is the less neces-
sary to insist, for in so many of the more marked seismic districts
there now exist organisations for the study of earthquakes. It
may not be out of place, however, to suggest that in all seismic
record-, and in every part if periodically published, the standard
time employed should be clearly stated. It is not universally
known, for instance, that, in Japan, Tokio time w.as replaced on
January i, 1SS8, by the time of 135° V.. long. In accounts from
Beluchislan, again, we cannot be certain whether Madras time
or railway time is meant, for both are used. The trouble of
inserting this important detail is hardly to be compared with
the confusion and error that may result from its omission.

C. Davison.

In the last report of the Earth Tremor Committee of the
British Association, reference is made to an observation of
earth-pulsations by Mr. C. D.ivison on the evening of June 3,
1S93, .It Birmingham, which was obtained liy the aid of Mr.
H. Darwin's bifilar pendulum. I take the following details
from the report : — .\t 5.43 p.m. (G.M.T.) the image was found
to be perfectly steady, liut .".t 6.29, when the observer returned
to the cellar, it was moving slowly and steadily from side to side
of the field of view, thus indicating the passage of a system of
earth-waves. At 6.42 the image had come to rest, but at 6.46
theoscill.ations commenced again, and continued to be visible with
varying amplitude until 8.13. After 8.13, though the observer
watched for two hours and a half, no further m ition was noticed.
The period of the waves was found by a number of observations
to be between fifteen and twenty seconds, and the range of
motion at its maximum one-eighth of a second.

Mr. Davison's observation is especially interesting, because it
corresponds exactly with a :erj' , wtraori/inary <iistiiy/'<iiit<- which
was registered by the horizontal pendulumsat Strassburg and Nico-
laiew. Amongst the considerable number ol disturbances com-
mon to both these places, that o( June 3 is certainly the most pro-
minent during the interval from January I to September 4. 1893.
In the accompanying illustration (Kig. I) the two curves, obtained
by photography, are shown side by side ; in correspondence with
the difference of longitude between the two places, the lower
curve wa-s moved I7'5 mm. to the left. The pendulum in both
cases was placed in the east-west plane. In the fnllowing notes
the time is Greenwich'Mean Solar Time, and is given in decimal
parts of the hour.

(a) .Slrasibiirg. — The disturbance begins suddenly and small
at 442, the curve having been perfectly sharp and steady before.
The range of motion increases to 4 mm. at 4 52 and decreases
at 469. It then again increases so as to make the curve dis-
appear entirely between 477 and 505. During the interval
the light-|)oint w.as displaced by 3^. mm. to the north, which
corresponds with a deflection of the pendulum towards the
south. At 482, the |)erson who keeps control over the instru-
ment entered the cellar, to look after it and to determine the
time correction, which is done by shutting off the light during

' Brit. Assoc. Rep., 1899, pp. 107.109.

December 27, 1894]

NATURE

209

a known interval of five minutes. He then locked the cellar,
and when he returned at 8'45 he was obliged to make a correc-
tion,' because the litjht-point had left the paper. Unfor-
tunately, he forgot to note down its exact place, but from the
inspection of the curve it is evident that at 5 '6', after a short
interval of steadiness between 5'25 and S'6i, the pendulum
received a sudden shock, which caused it to oscillate, and at
the same time produced a deflection, by which the light-point
was probably brought off the lower edge of the paper, from
which it was distant 4S mm. at the time of the shock. There
can be no doubt that such was the cause of the disappearance
of the curve, for the base-line runs on perfectly undisturbed,
which is a sign that the instrument continued to be in good
working order, as usually. From S'45 to 965 the motion is
small; and from 9'65 till Il'l6 the curve is nearly perfectly
steady.

\\. 1 1 '16 a new disturbance begins; the range of motion is
very small at first, but increases to 5 mm. at li'45, and to
10 mm. at ii-6o ; at i2'io the disturbance, which is much like
the first one, comes to an end, and is again followed by a steady
part of the curve.

At I2'26 commences the last disturbance, which at 1247
increases to 6 mm. Between I2'73 and 13 '03 no traces of the
curve are visible, and during this interval a displacement of
loi mm. has occurred, which indicates a deflection of the

At II 05 a new disturbance begins, which increases suddenly at
11-36, diminishes a little at 123, and increases again at 1247
From 127 to i3'22no traces of the curve are visible. At I3'9.
the motion decreases considerably, and after another small in-
crease at I4'87 reaches its end at I5'I7.

The figure shows that the motion at Nicolaiew is much more
considerable than at Strassburg. Whilst at the latter place the
whole disturbance is divided into four distinct parts, which are
separated by moments of nearly perfect steadiness, at Nico-
laiew the first and second, as well as the third and fourth part,
each form a continuous disturbance.

If we denote by V the relative strength of a shock in a direc-
tion normal to that of the pendulum, by a the range of motion,
measured on the curve, by U and T the distance between the
photogra|jhic drum and the pendulum mirror, and the period
of oscillation of the pendulum, then we have the following
relation between the observations in two different places : —
V, ^a, AT.,
V„ a. ■ fl-jT,
In the present case

dy - l-8m., (/o = 4'6m., Tj = 170s., To = lo'2s.,

thus Sj?— • A shock of the same strength therefore produces

at Nicolaiew a disturbance ij; times as large as at Strassburg.

Strassburg

s«.waa!,-'"'""*ti'*

yH«»«»''*'"^^'

^«>^tWMIIW«<

Or. M. T.

4 5

Nicolaiew

10

12

13

14

15

16

17

Fig. I. — Earthquake Disturbance observed at Strassburg and .it Nicolaiew on June 3, 1393,

pendulum towards the north. The motion continues to be
visible until I4'45 ; the curve then resumes its nearly steady
appearance, which is once again interrupted by small motion
at 14-95.

(i) Nico.'au-w. — The following details were communicated to
me by Prof. Kortazzi, who informed me that on this day he
went down into the cellar one half-hour later than usually, at
6-54, when he found that the light-point had passed from the
paper on to the brass rod, which serves to clamp the paper, and
was swinging considerably. From this reason the light-point
could leave no traces on the paper between 5 95 and 6 62. The
disturbance is very large and of long duration. It commences
at 4-32 and reaches its first maximum at 4-80, when the range
iSi-bomm. Strong motion continues until 8-4. From the copy
of the disturbance, which Prof. Kortazzi kindly sent me, and
which is represented in the above figure, it appears that at about
S'77. Of iim. licfoic the light-point was prevented to trace a
curve, by passing on to the brass rod, the curve was suddenly
interrupted, which shows that the pendulum was performing
large oscillations. Between 9-72 and 1 1 '05 the motion is small.

' In the original photograph the second part of the curve is much dis-
placed, in the s:ime way .is the third part after the interruption. This was
altered in the figure to economise space.

NO. 13 13, VOL 51]

In comparing the two curves, it is evident that the different
intensity of motion at the two places is not due to the difference
in the values of the instrumental constants. The reason why
the motion of the pendulum is so much stronger at Nicolaiew is
this, that the soil consists down to a great depth of sand, which
is particularly favourable for the development of strong motion.
In this respect Nicolaiew resembles the two former stations,
Potsdam and Wilhclmshaven. Many facts tend to show that
the soil at Strassburg, though often disturbed by small earth-
quakes of distant origin, never oscillates as much as at the fore-
named places. It would not be right, therefore, from the mere
look of the curves, to draw the conclusion that the earthquake —
if such was the cause of the disturbance — must have originated
at a place considerably nearer to Nicolaiew than to Strassburg.

Until now I have not been able to find a record of a pheno-
menon which might possibly be connected wiih this disturbance.
From its size and duration, one ought to think that it must have
been caused by a strong catastrophe, surpassing anything that
has been reported during the last year from all parts of the
world. But it is strange that the magnetic recording instru-
ments at Potsdam have shown no trace of motion, and that
nothing is reported from the delicate seismological instruments
which are at work in Italy.

2IO

NATURE

[December 27, 1894

The case is remarkable in more (han one respect. Displace-
ments of the light-point, which, though the oscillations of the
pendulum were much larger generally, were scarcely noticeable
daring the former observations with this instrument at other
places, often occur at Strassburg. I am inclined to think that
they are due to a vibratory motion of the ground, which scarcely
affects the motion of the pendulum, but may cause a change in
its position with regard to the sletl pivots. These vibrations
appear to be more easily propagated by the soil at Strassburg
than at Nicolaiew, for though small displacements occasionally
occur at the latter place, they are considerably smaller. This is
particularly evident in the present case, where the only displace-
ment worth mentioning is connected with the shock at 5'77- O"
the other side, the displacement at Strassburg, which produced
the long break in the curve, is far the largest that occurred
during one and a half years' observation. It is much larger
than that which tork place when an iron hook was driven into
the pillar on the side opposite to the pendulum.

Our figure shows that the displacements of the pendulum were
comparatively larger during the first and second than during the
third and fourth disturbance. The change during No. III. is
about 1 mm. Another fact worth noting is that in the two first
cases the pendulum is deflected towards the south, and in the
two last towards the north. This seems to indicate, if one
considers the special arrangement of the instrument, that the
motion arrive I from the north in the first and second, and from
the south in the third and fourth case. The displacement of the
pendulum at Nicolaiew at 577 is also directed towards the south,
in accordance with the observation at Strassburg. ' The above
conclusion is founded on the supposition that the displacement
is produced by a single shock, which causes the steel-points
connected with the stand of the instrument to slip on the agate
cups. In reality, the motion is probably much more compli-
cated, and perhaps one is not justified in supp'>sing the direc-
tion of the shock to be opposite to the deflection of the pendulum.
The comparison of the observed times, indeed, leads to a
different result.

The following table gives a summary of the observations : —

.\gain the times of disappearance of the curve or of maximum
motion are separated by nearly the same interval, viz., at
Strassburg III. -I. = 6 S^h., IV. -II. = 7l2h.,i .and at Nico-
laiew IV.-II. = 69h. The duration at Strassburg of No. I.
is oSjh., and of No. II. o'94h. ; the duration of No. III., if
we omit the last part, in which the motion was very small, is
2S4h., of No. IV. 2'69h. .A.t Nicolaiew, during the first half
of the disturbance, the strong motion ends 4oSh. after the
beginning, and the second part Lasts 4'l2h. The intensity of
I. and II. is evidently larger than that of III. and IV.

We will now see if the direction of motion can be determined
by the observations.

I. Though the first trace of motion is o'loh. earlier at Nico-
laiew than at Strassburg, yet it is probable that the corresponding
moments are those of the disappearance of the curve at Strass-
burg and of maximum oscillation at Nicolaiew, or 4'77h. and
4'8h. To judge from the copy, which I'rof. Kortazii sent me,
the latter value is only approximate. The difference in time
is certainly small, and the direction of the motion remains
rather uncertain ; the general aspect of the figure, however,
makes it more probable that it came from the east.

II. The time of disappearance of the curve at Strassburg,
56lh., is probably correct within oo2h. or oo3h. Mr.
Daviison's oliservation shows that the motion, which in this case
appears to have commenced suddenly, h.id not reached Bir-
mingham -at 5 72h.; on'the other hand, the disappearance of the
curve at Nicolaiew took place at 5'Sh., or about 12m. later than
at Strassburg. If these times were all correct, and if the three
moments really corresponded with the same phase, the centre of
disturbance ought to be looked for somewhere at the south-west
and not too far away from Strassburg. This, however, is a very
improbable result. Mr. Davison's instrument could only indicate
an east-west tilt, and perhaps the motion h.ad already set in when
he left the instrument .it 572h., but was not perceptible
enough in the east- west direction.^

The two other observations make it nearly certain that the
motion arrived from the west.

III. The case is very much like No. I. : probably the motion

Disturbance

Strassburg.

Nicolaiew

I

Birmingham

No. I.
(displacement - 3"5mm)

No. II.

( displacement prn!iably

i. - 48mni.

No. III.
(displacement -h imm.)

No. IV.
(displacement -H 10.3mm.

4"42 first trace

4°52 increases 4mm.

4'69 decreases and increases again

4'77 curve disappears

505 reappears

h.
4-32

first trace

5-25 end

5 61 new shock

curve steady

during the

interval

8 '45 \ light point corrected
^9-65 J motion small I ^^^^ly^j^^jy

' 1 1 45 first increase 5mm.

I I i°6o second increa.^e 10 mm.

l i2'io end ) curve

I2'26 first small motion ) steady

1 2 47 increase 6mm.

1273 curve disappears

1303 reappears { ^^,jg„ j^,^,,,

1 4 '95 new small increase

4'S first maximum>6omm.

5'S curve disappears
strong motion

small motion
sudden increase

diminishes

8-4

972 (
1 1 OS )
11-36

12-3

127
1322

13-97
14-87
15-17

curve disappears
,, reappears
decrease of motion
new increase
end

5-72 the image was found

to be steady
6-48 strong motion
6-70-6-77 steady again
8-22 end

When looking ov-'"--— •■— lut-, .i.v .> inclined to think that
the remarkable con between the several phases of

the disturbance cat: ■ to chance. If we take as the

beginning of a ditlurbance the moment when its first traces are
visible, we have the fallowing differences at Strassburg : —
II.-I. = i-igh. and 1 V.-III. - i loli , III.-I. = 6-74h.,
IV.-II. = 6-65h. At Nicolaiew, where 1. and II., III., and IV.
appear as a single disturbance each, we have III. -I. = 6-73h.

• In the hjjure the i.ulve ti displaced in an op('0»ile direction, but ifli* i»
Um caM l>ec.iu«e the drum it-ind» well nf the pcri'liiluin :it Nicolaiew,
aad ea«t of it at StraAtburg.

arrived at Nicolaiew first, but its direction cannot be determined
with certainty.

' The licRinninK of I!., tliougb sudden and sh.irp. need not neMssarily
coinciilc «itli the inovcmL-ni of greatest motion; in this case the dilTerence
IV.-II. wcmld have a smaller value. _ ■ ,. o 1 -t

- The distance between Strassburg and fiirmlngham is about 800 kilo-
metre*. 1 .- .

J [Much weight cannot be attached to the absence of observed motion al
BirniinKhani at 073h. The image of the wire was .nljuiied on the cross-
wile of the teliscopc without diffiiiilty. and must have remnincd practically
in contact for a lew seconds. A small movement, with a period so long as
twenty seconds, might easily at this time have escaped notice.— C. D. I

NO. 1313, VOL. 51]

December 27, 1894.]

NATURE

2 1 1

IV. The curves again disappear at about the same time ; but
to judge from the time of greatest steadiness before the disturb-
ance commenced at Nicolaiew, it appears to have reached
Strassburg first. The last small increase at l4S7h. and I4'95h.
is, on the contrary, earlier at Nicolaiew than at Strassburg,
but this might be an independent disturbance. After the
strongest motion, the light-point resumes its steadiness much
sooner at Strassburg than at Nicolaiew.

It is evident that the case is, on the whole, not favourable to
an hypothesis which first occurred to me, that all four disturb-
ances migbt have been caused by four successive waves emanat-
ing from a single centre and a single shock, and circulating
round the earth. The fact that II. and IV. are more consider-
able than I. and III. does not appear of much importance, for
it is proved by many examples that the intensity of a disturb-
ance is not alone dependent from the distance from the centre ;
but, if the hypothesis were right, disturbances III. and IV.
ought probably to be much smaller. Besides, the velocity of
about 100 km. per minute would be a very small value com-
pared to those determined on other occasions.

I reject this hypothesis, but I do not think it improbable
that I. and II., III. and IV. may be connected in the way just
mentioned, and that both disturbances came from the same
part of the world. It is the principal object of this com-
munication to induce persons interested in the subject to study
carefully the records of all self-registering instruments. If the
disturbance originated at the bottom of the sea, something
about it might be found in the ship journals, the tidal records
might show a trace, or perhaps the magnetical records at distant
places. I have many proofs that the .'-ize of a disturbance,
traced by the horizontal pendulum, is not always a measure
for the importance of the catastrophe which produced it ; but
in the present case many instances indicate an extraordinary
phenomenon, of which an account is likely to appear sooner or
later, in case it should have taken place at some remote corner
of the earth.

Merseburg, May i8,

P.S. — Some time after having written the above, I received
the third volume of the Seismolo;^ical Journal of Japan (1894),
in which there is an interesting paper by F. Omori on the erup-
tion of Azuma-san in 1893. From this paper it appears that
the volcano was in an active state since May 19, when an ex-
plosion took place, which was followed by two other one* on
June 4, 4.10 a.m., and on June 7, of which the former is said
to have been the strongest. It was accompanied by an earth-
quake, which was felt at the meteorological station of Fuku-
shima. Supposing the above time to be Standard Time (9h.
east of Greenwich), the explosion took place at 7h. lom. p.m.
G. M.T. on June 3, and thus it is seen that it coincides with a
part of our great disturbance. I do not, however, believe that
this is more than a casual coincidence, for the two other erup-
tions produced no disturbances. It is also a well-known fact
that volcanic eruptions, even when accompanied by earthquakes,
are generally not felt to any great distance, unless they bear a
very violent character, like the eruption of Krakatoa ; but from
Mr. Omori's description it appears that the eruption of Azuma-
:n was nothing very extraordinary. I therefore believe that
we must wait to find another explanation for our disturbance.
E. VON Rebeur-Paschwitz.

EXPLOSIONS IN MINES.

T N a lecture on some modern developments in explosives,
given at the Society of Arts on December 17, Prof. Vivian
B. Lewes threw out a suggestion as to the cause of explosions
in dusty mines free from fire-damp, which explains the
anomalies which have presented themselves in several recent
explosions.

It was pointed out that until quite recently explosions in
mines were always attributed to the accidental ignition of mix-
tures of air and methane, to which the name of " fire-damp "
is given, and undoubtedly this cause is the prime factor in this
class of disaster, and the introduction of such precautions as
safety-lamps at once brought about a considerable reduction in
the nuniber of explosions taking place. Many disasters, how-
ever, still continue<l to occur under apparently mysterious cir-
cumstances, the conditions being such that any large propor-
tion of methane in the air of the mine appeared practically

impossible, but investigations of such explosions showed that
coal-dust in a dry and finely powdered condition had generally
been present in the mine at the time of the explosion, and the
coked residue of this dust was found afterwards on the surface
exposed to the explosive wave, and years of experimental in-
vestigation by scientific men of the greatest ability proved the
fact that air containing so small a proportion of methane as to
be itself perfectly non-explosive, becomes a good explosive
again when holding dry and finely divided coal-dust in suspen-
sion, and within the last few years explosions having taken
place in mines, which have always been celebrated for their
freedom from any trace of methane. Further experiments
have been made by Mr. H. Hall and Mr. W. Galloway, who
have shown that the violent ignition of dust-laden air is pos-
sible by a blown-out shot, even if free from any trace of marsh
gas, and there is evidence to show that the explosion is de-
veloped in throbs or waves.

It is therefore found that the explosions in mines may be
brought about, first, by the ignition of a mixture of methane
anil air, in which the former rises above a certain percentage ;
secondly, by mixtures of air, coal-dust, and methane, in which
the amount of the latter may be excessively small ; lastly, by
mixtures of coal-dust and air. With regard to these explosions
caused by coal-dust and air alone, the Royal Commission on
Explosions from Coal-Dust in Mines, in their second report,
published this year, say : —

" On a general review of the evidence on this point, we have
no hesitation in expressing our opinion that a blown-out shot
may, under certain conditions, set up a most dangerous explo-
sion in a mine, even where fire-damp is not present at all, or
only in infinitesimal quantities ; and while we are prepared to
admit that the danger of a coal-dust explosion varies greatly
according to the composition of the dust, we are unable to say
that any mine is safe in this respect, or that its owners can
properly be absolved from taking reasonable precautions
against a possible explosion from this cause. But even if we
had been able to come to a diiTerent conclusion, and to agree
with the minority of the witnesses examined, who think that
coal-dust alone cannot originate an explosion, we should still
have to call attention to the serious danger which results from
the action of coal-dust in carrying on and extending an
explosion which may originally have been set up by the
ignition of fire-damp."

One of the most interesting and instructive explosions which
have taken place recently was that which occurred a little more
than a year ago at the Camerton Collieries, Somersetshire, in
which as far as investigation could go, no trace of combustible
gas could be found in the mine at any peiiod prior to the ex-
plosion or subsequent to it, and in which everything pointed to
the explosion being entirely due to the presence of dry coal-dust
in the air.

Of absorbing interest, also, are the experiments made by Mr.
Hall at the latter end of 1S92 and the early part ol 1S93, and
reported upon by him to the Secretary of State on January 23,
1893, in which he shows by conclusive experiments that dry
coal-dust under conditions frequently present in coal mines and
in the entire absence of fire-damp, may be inflamed by a blow-
out gunpowder shot, and cause a disastrous colliery explosion.

The evidence which can be collected from the investigation
in the Camerton disaster, and from Mr. Hall's experiments,
point to a cause for such explosions, which has apparently
been overlooked, and which Prof. Lewes thought worthy of the
gravest attention. Both at the Camerton Colliery and in Mr.
Hall's experiments, powder w.as the blasting agent used, and
such powder as is employed for this purpose, gives amongst the
products of combustion nearly half the volume of permanent
gases in the condition of carbon monoxide, methane, and
hydrogen.

In the Camerton explosion, it seems probable that about
l,j lbs. of such powder were used in the shot which caused the
disaster, and this quantity of powder would i;ive, roughly, a little
over three feet of inflammable gas, which when mixed with pure
air would give over 10 cubic feet of an explosive or, at any rate,
rapidly burning mixture, and experiments which have been
made upon the effect of fire-damp and dust combined in causing
colliery explosions show conclusively that even when the fire-
damp is present in such minute quantities as to form a mixture
very tar removed from the point of explosion, it still makes the
mixiure of coal-dust and air highly explosive ; and from experi-
ments which Prof. Lewes has made, it is clear that traces of

NO. 13 I 3, VOL. 51]

2 12

NATURE

[December 27, 1894

carbon monoxide will do exactly the s.im: thing when the air
is laden wi'.h coal-dust, whilst the temperature of ignition is
slightly lower than with methane, so that in the cise of the
Camerton Colliery, it being perfecily well ascertained that the
air was charged with coal-du-t, the probabilities are that not
10 feet, but a lar larger volume of explosive mixture was formed
by the rapid escape of the products of c imbusiiin into the ooal-
laden air ; and this Ixring ignited, ei'her by the tlame or red hot
solid products driven out into it by the blown-out shot, would
initiate a considerable area of expIo>ion.

The classical researches of Prof. H. Dixon have shown that
hydrocarbons and, probably, carbon burn in air lo carbon
monoxid>-, and that this carbon monoxide will not form explo-
sive mixtures with air, or even with oxygen, if they are abso-
lutely dry ; but if water vapour is presen', they explode owing
to the oxidation of the carbon uionoxide to dioxide, causing the
propagation of an explosive wa%e, which reaches its maximum
velocity when the percentage of water vapour, between $ and
6 per cent., and inasmuch as the air of the mines would always
contain some moisture, and as the products of combustion also
would give a large volume of water vapour, these requirements
would be amply fulfilled.

Still more conclusive on this point were Mr. Hall's experi-
ments. In these a charge of blasting powder was fired
from a cannon suspended in a shaft, the air oi which was proved
by careful chemical analy^is to be absolutely free from any trace
of cou^busiible gas.

In order lo get some idea of the condition of the air inside
the pit during the explosion, samples of air were l.aken and
were analysed. Two brass tubes were fastened to the rope that
was used to lower the cannon, one twenty yards from the
bottom, the other forty yards from the bottom.

These tubes were so arranged and constructed that the explo-
sion, as it passed the tubes, unsealed the outlet pipe, and the
escaping water sucked in a sample of air which was (rapped by
a special arrangement, and kept in the tu ^e until the rope could
be wound up. By this method it was intended that the sample
of gas taken should represent that state of the air whilst the
flame was passing, or directly afterwards.

The tube nearest the bottom, as the analysis will show, did
partly collect the gas in the above condition. The tube at the
top, however, commenced to act premature y, an I was probably
started by the sound wave which preceded the explosion. This
tube simply contained ordinary air.

The following is an analysis of the gases found in the lowest
tube : —

Per csnt.

Oxygen ... 3 9

Nitrogen ... 75-9

Carbon dioxide ... ... ... iz'i

Carbon monoxide ii'l

This ingenious arrangement was due to Mr. W.J. Orsman'
and it isprobablyihefirst successful attempt which has been mad
10 get a sample of gas during the pro rcss of explosion, an
there is not the slightest doubt that the presence of such an
amount of carbon monoxide converts mixtures of coal dust and
air into a highly explosive body.

As ihe explosion takes place, and as the carbon monoxide
ready produced is oxidised to carbon dioxide by the action
upon it of water vapour present, a.rd also by its direct com-
bustion with oxygen, the hydrogen of the water vapour is set
frte, whilst ihe heated coal-dust also yields certain inflammable
products of disiillaiion to the air, and partial combustion also
of ihe coal du-t gives a considerable proporii n of carbon
monoxide once more, and these driven r.ipidly ahead of the
explosion form with more coal-du'.t and air a new explosive
zone, and so by waves and throbs the explosion is carried
through the dust-laden galleric-> of the min-r.

The experiments made by Mr. Hall, and invcsiigitions in
various colliery explosions, mikc It ariundanily m.inilcit that no
explirtive should be licensed for use in mines unless it can be
ab-olutrly proved that it give- off no imflamm iiile products of
combu lion. The following table will show ihe results given by
some of ihe explosives most largely ucd, which point very
clearly to the fact thai, wiih therxccp'ion of the Sprengcl ex-
plosives, such as roburlle and nitr.iKlyccrinc, none of the
bodies in use conform to this iniporiani rer| Jireln^:nt.

Products of Combustion of Blasting Explosives.

Combustibles.

Powder.

Carbon dioxide. Crirbon monoxide.

Gunpowder ... 506

Blasting power ... 321
Sprengel explosives —

Roburite ... ... 320

Ammonite ... 330

Nitroglycerine explosives—

NitrogUcerine

Gelinnite ...

Carbonite ...

Blasting gelatine

63 o
25 'O
190
365

105

33 '7

nil

nil

nil

7-0

"SO

Hydrosen and
marsh gas.

3'i
7'9

nil
nil

nil

nil

26 'o

S-6

Whilst not only these considerations, but Mr. Hall's experi-
ments, point to the absolute necessity of legislative enactments
at once forbidding the use of blasting powder in any coal mines,
no matter how free they may appear to be from fire-damp or
from dust, if the returns made as to deaths ciu^ed by gun-
powder and o'her explosives in mines for the year 1S93 are
examined, it will be clearly seen that theexcbision of gunpowder,
in handling alone, would do a'vay with So per cent, of the
accidents. So that if explosives of iti-f Sprengel class were em-
ployed, accidents due to the explosives used would be prac-
tically eliminated from the mining death loil ; and it is only a
question of time as to when England will icllo* the action of
France and Germany in altogether prohibiting the use of blast-
ing power in dusty mines.

THE POSSrB/LlTIES OF LONG-RANGE
WEATHER FORECASTS.'^

T F we had perfect command of this subject, we should be able
to trace the motion of a panicle of aqne us vapour from
point to point over the whole earth, and could predict whether
at any lime in the future it will fall a-s rain, or rise and lly away
as an invisible gas. In the absence of this higher knowledge
the only long-range forecasts that we are at present able to
make are based upon empirical and very imperfect rules deduced
from our study of the accumulated clim.ilological sl.itistics. Of
course, sech predictions do not imply any special knowledge of
meteorology. Among the methods adopted in long-range
forecasts are the following :

(a) The average rainfall, temperature, &c., for any period,
such as a month, and deduced from many yeais of observation,
is called the normal. The excess or deficiency of this month in
any given year is called llic departure for that year. A general
prediction may be made to the elTecl that the raii'fall for a given
month and place may be expected to lie within the range of the
values indicated by these known departures.

(/') The scries of annual or monthly values just mentioned
gives us the means of finding out whether iheie is any simple
sequence or connection between them and (he .ipparently un-
connected values that occur (roni year to year. Thus, it some-
times happens that rainy seasons come alter two or three dry
seasons, or ihat after the same month has been dry in three
successive years, one is then justified in pr< dieting a wet month.
Thus, Governor Raw~on elaborated a sysiem lor ihe prediction
of rain and the sugar crop in liarbados.

{<■) Slight but appreciable widespread, rather regular fluc-
tuations of temperature, pre-sure, and rain have been revealed
in the climate ol Europe by Dr. Biiickni-r, who linds that a de-
ficient temperature and an excess of r.iin have alternated with
excess of temperature and deficiency of rain in periods of thirty-
six or thirty-seven years during the past two or tlnee centuries ;
the glaciers increase and dimmish m volum- , ur advance and
retreat, in correspondingly regular but somewhat retarded
intervals. Predictions may be based on these well-establisb.ed
periods.

((0 Droughts are sometimes due lo what happens in distant
regions: thus, if there is a heavy sno« on the llii'alnyas during
the winter, there is a special liability to diought in lower India
in the follo«ing summer, so that the putliciionof a drought
may be basid i.pon the reports of snow tall in a rlisiant region
several months beloie the drought occurs ; but • ther droughts
may occur wiihout this preliminary sno«-lall. This connection

' Keprini of .in pnicl? contributed by Prof. Cleveland Abbe to the
U.S. l^toHthty tt'titllicr Kevitw.

NO. 1313, VOL. 51]

December 27, 1894]

NA TURE

2 I

is, so far as at present known, a local, arbitrary, or accidental
one, and has not yet been found to recur in any other portion
of the globe.

(i) Droughts or floods may occur every year in some portion
of an extensive region, so that it may become possible to predict
the occurrence in a special section one year because one has
occurred in another section a previous year. Thus, a serious
drought in the lower Indian peninsula has, on live occasions,
been followed by one in northern India the next year.

(/') If we had maps of the weather of the whole globe for every
month for a long series of years we should, undoubtedly, be able
to find many similar coincidences, so that a drought for a given
section might be predicttd from the rain-fall, the snow-fall, the
temperature, the pressure, or other conditions in a distant part
of the globe. As a rule, important climatic crises are the results
of changes that have been going on slowly for a long time in
distant parts of the earth. The general circulation of the air
constitutes a complex system in which the areas of high pressure
and dry clear air are the results of slowly descending winds
moving toward the equator ; the general rains are formed
wherever a descending current of air, a mountain range, or other
obstacle has an opportunity to push up the moister air of the
earth's surface. From this point of view rainy and dry and cold
and hot seasons depend largely upon the varying relations of the
upper and lower currents to the continents and even to each
other. The long-range prediction of the climate of any season
must depend upon the prediction of the general character of the
horizontal and vertical movement of the air. Ir. our present
geological epoch the continents are permanent features, and «e
consider only the changes that take place in the atmosphere,
but in studying the climatic changes of earlier geological epochs
we have to consider the changes in elevation of the continents
themselves.

(.j) Such apparent connections as that between snow-fall on
the Himalayas and the subsequent drought in northern India
are not to be thought of as cause and effect respectively. It
might be argued that the layer of snow must be evaporated, or
melted, thereby absorbirg more heat than would have been
required if it had fallen as rain and rapidly drained away ; but
this cooling influence is distributed over many weeks, and
through the immense quantity of air that has passed over the
snow -fields during the winter and the spring, and is thereby
rendered too slight to have any great local influence in India.
A broader view of the subject shows us that the winter snow-
fall and the summer drought are simply two features ol an
extensive system of changes in which the whole atmosphere of
the earth takes part. The whole globe may be divided into
regions where the lower stratum is moving either horizontally
or upward or downward, and where the upper stratum has
similar diversities of movement. These s)stems of motion
determine whether we shall have fair weather or rain, hot
weather or cold, fr< m day to day and accumulatively from
month to month. New these three movements are related to
each other in such a way that the sum total of the energy
involved throughout the atmosphere is sensibly constant, while
the localities at which the upward and downward motions are
taking place are undergoing perpetual changes.

The centres of high pressure over the oceans and continents
slowly sway east and west or north or south ; the paths of the
storm-centres vary in a similar manner to suit the changes of
these larger areas, and ibe centres themselves move rapialy or
slowly in response to these same changes. The air that ascends
between the northern and southern tropical regions of high
pressure descends scmetinjes in high latitudes, giving them cold
weather with rain or snow ; at other times in low latitudes, giving
them warm weather with droughts. It mailers not whether
the droughts in southern regions chronologically follow or
precede the snows of ihe northern regions ; in neither case can
either one be spoken of as the cause of the other, but each is
in its turn the result of changes in the so-called general circula-
tion of the atmosphere.

This general circulation, wilh all its variations, diurnal, annual,
and secular, is dependent uj on the intrinsic density of each
portion of the atmo^)jhere and on numerous forces, such as the
heat received from the sun, the attraction of the sun, moon,
and earth, the resistance offered by the irregular surface or the
earth, and the interaction of slow and rapdly moving masses
of air. The proper study of ihis subject constitutes the
application of hjdrodyramics lo meteorology.

The meteorological problem has some analogy to that oflered

NO. 13 I 3, VOL. 51]

by the hydrsulics of ihe Mississippi River, where cut-ofis, cave-
ins, mud-tanks, end crevasses are conlir,uaIly forming and
re-formirg. We do ret e>pecl tote alle to foretell when and
where these will occur many years in advance, but we do keep
a watch en ihe condition of the river; and when conditions are
favour able for Ihe formation of any important charge, we watch
the pr ocess until Ihe cataslrorhe beccmes more or less immi-
nent, and then begin to trake estimates, that may be called
predict ions, as to the exact lime and place of the event.

In m eleorology the best we can do at present in long-range
predictions is to chart and study Ihe occurrence of abnormal
weather conditions over the whole globe; these phenomena
must be inleipieled in the light of all the knowledge we have
of Ihe mechanics of the atmosphere, for they are the results of
purely mechanical operations covering the whole range of the
mechanics of heat, gases, and vapours.

SCIENTIFIC SERIAL.

The Quarterly Journal of Microscopical Science, November.
— On Julinia, a new genus of compound ascidians
from the Antarctic Ocean, by W. T. Caiman (plates
1-3). The colony is described as irregularly cylindrical in
shape, measuring 78'5 cm. in length, and from l'5 to 25 cm.
in diameter ; it was found fl( ating on the surface of the sea in
the north of Erebus and Terror Gulf; a consideral le quantity
was seen ; no attaching fibres were found, but it was probably an
attached form. The species is described 2is jfuUin'a amlralis,
and it is provisionally placed in the Distomida?. — Hermaphrodi-
tism in mollusca, by Dr. Paul Pelscneer (Ghent) {plates 4-6).
Hermaphroditism is found in Ihe Amphineura, the Gastropoda,
and the Lamellibranchia. It is not self-sufficient, is sometimes
prolandric ; it would seem to the author to be not a primitive
arrangement, but to be derived from the unisexual state, and to
have been established upon the female organism. — Description
of Ihe cerebral convolutions of the chimpanzee known as
" Sally," with notes on the convolutions of the brains of other
chimpanzees and of two orsngs, by W. Blaxland Benham (plates
7-11). — On the inadequacy of the cellular theory cf development
and on the early development of nerves, particularly of the third
nerve and of ihesjmpathetic, in Elasmobranchii, by .'\dam Sedg-
wick, F.R.S. More than len years ago the author called atten-
tion to ihe inadequacy of the cellular theory of development :
** Embryonic development can no longer he looked upon as
being essentially the formation by fission of a number of units
from a single primitive unit, and the coordination and modifica-
tion of these units into a harmonious whole. But it must
rather be regarded as amulliplicatienof nuclei and a specialisa-
tion of tracts and vacuoles in a continuous mass of vacuolated
protoplasm.'' And '' although opinions have charged on this
important subject, and although there are some who think that
they have escapee! from the domination of ihis fetish of their
predecessors, yet as a iratler of fact the cellular theory of
development is still rampant, still blinds men's eyes to the most
patent facts, and still obstructs the way of real progress in the
knowledge of structure. " When a student begins his zoology
he is told that "ihe various structures present in a protczoon
are all parts of one cell, whereas in a metazoon the various
parts are composed of groups of cells which differ from one
another in structure." When in a later yeriod of his studies he
begins embryology, "the importance and distinctness of the
cell meels him at every step, from the complete cleavage which
he is led lo believe is primitive, lo ihe develoiirent of nerves
according lo the views of His." If we take the so-called
mesenchjme tissue cf elasmc branch embrjos, it is described as
consisting of " blanched cells lying between the eclo- and the
endo-derm," while, as a matter of fact, " the separate cells have
no exislence," hut "there is a reticulum of a pale non-staining
sutslance holding nuclei at its ne des. And far from the
develoiment of nerves being an outgrowth of cell-processes
from certain central cells, it is simply a differentiation of a
substance which was already in position." This important
memoir is so cerdensed as to make it extremely difficult to
condense it further, tut enough has been given 10 indicate its
nature.— On Bin hernia (Oiijiia, n. sp. , from the Gold Co.a;t, by
W. B. Btnhani (plate 12). "This large species (20 inches)
was found al Axim in Ihe Fanlee ccurlry, on the west coast of
Africa.

214

NATURE

[December 27, 1894

SOCIETIES AND ACADEMIES.
London.

Royal Society. November 22. — " .\ Delerminalion of the
Specific Heat of Water in terms of the International Electric
Units." Uy Prof. .Vrthur Schuster, F. R.S., and William
Gannon, Exhibition (18511 Scholar, Queen's Colle(;e, Galway.

This research was originally undertaken by Prof. Schuster
and Mr. H. Uadley, before the authors were aware that Mr.
E. H. Griffiths was engaged on a similar investigalion. After
a number of preliminary experiments, and just as the linal
arrangements for the conduct of the mea>uremenls were being
definitely made, Mr. Hadley, on his appointment to the head-
mastership of the School of Science and Art, Kidderminster,
had to leave Manchester.

On Mr. Iladley's departure, Mr. W. Gannon took his place.
From the former gentleman we received a good deal of help in
the devising and construction of some important parts of the
apparatus.

The principle of the method we have used is extremely
simple. The electrical work done in a conductor being
measured by / EG//, where E is the difference of potential at
the ends of the conductor, C the current, and t the time. We
keep the electromotive force constant, and measure / Qdt
directly by a silver vollame'er. We do not, therefore, require
10 knew the resistance of the wire, and we thus avoid the
difficulty of having to estimate the excess of temperature of the
wire over that of the water in which it is placed. We also gain
the advantage of not having to measure time, and thertfore to
be able to complete the experiments more quickly than we
could have safely done if the length of time the clirrent passed
had (o be measured with great accuracy.

Our 6nal value is

J = 41804 Joules on the mercury scale of hard French glass,
4'I905 on the nitrogen scale,
4'I9I7 on the hydrogen scale,

at a temperature of ig"'!.

In comparing our results with that of other observers, we have
in the first place to consider the value which Mr. Griffiths has
obtained in his very excellent series of measurements. His final
result (Roy. Soc. Proc. vol. Iv. p. 26 ; Phil. Trans, clxxxiv. A

(1893) is

J = 4'l982(i -0-00266 fl- 15) y. 10.'

This refers to the nitrogen thermometer. .\t a temperature of
yf'l, the value would be reduced to 41936, which corresponds
to our 4' 1905 at the same temperature. Griffiths' value is to he
increased slightly, owing to the fact that he really measures the
difference between the specific heat of water and of air. This
would increase the value of J by "ooi i about, so that the value
of J at I9°"l would be raised to 41947 y. 10", which is exactly
one part in a thousand larger than ours. The difference is small,
but must be due to some systematic error, as bnih Giiffiths'
value and our own agree so well with each other, that ordinary
observational errois and accidental disturbances could not have
produced so large a difference in our results. The least satis-
factory part of a calometric measurement must always be the
applicali 'n of the cooling correction, and «e have considered
it of great importance to reduce that correction as much as
possible. The uncertainty of the cooling correction does not
necestarily depend on its value ; thus we can much diminish it
bjr starting, as we have done in the third series, with the initial
temperature of the calorimeter about as much below that of the
water jarket as the final temperature is above it; yet the
uncertainly of the correction does not seem to us to be
dimini-hcd by thai process. We may reasonably estimate the
uncertainty due to the cooling correction, by calculating what
the error m the observed rate of cooling, either at the beginning
or the end of the experiment, must have been in order to pro-
duce a difference of one p.irt in a thousand in the final result.
We find in our own experiments that the error must have
amounted to more than 15 per cent. We consider it unlikely
that so large an error occurred always in the same direction.
Apart from the co ding correction, however, it is dilficult to see
how a difference one-lcnih per cent, in our result can be pro-
duced unless by the accumulation of a number of small errors
The difference between our value of the equivalent and tha!
NO. I313. VOL. 51]

of Mr. Griffiths are, however, of sm.iller importance than the
difference which exists between them and the equivalent as
determined directly by Joule, Rowland, and Miculescu.
Joule's latest value, which is the only one which needs con-
sideration, is 77265 foot-pounds, at 617 F. The number
refers to the degree as measured by Joule's mercury thermo-
meter. RowKind adds to this a correction to the air thermo-
meter of about 3, and another small correction for a change in
the heat capacity of the apparatus, which brings the value up
to about 776. The correction to the air thermometer has been
obtained by means of a comparison made by Joule himself with
one of Rowland's thermometers. Joule's original thermometers
have been temporarily placed by Mr. B. A. Joule in the hands
of Prof. .Schuster, in order that an accurate comparison may be
instituted between them and modern thermometers. .\ full
description of the comparisons made will be given on another
occasion. The result arrived at shows that the correction is less
than that assumed by Rowland, and would bring his value up
only to 775 at the temperature indicated.

Great weight must be attached to Rowland's determination,
which at the temperature to which Joule's number applies is
7776, and at I9°'i, 7761, corresponuing to our 77S5.

Ei}iiivaleiil in foot-pounds at Greenwich at ig"'! referred to the
"Paris" Nitrogen Thermometer.

GrifTiths.

Schuster and
Cinnon.

Joule. Rowland.

774 776-1 779-1 77S'S

We now turn to an investigation of .Miculescu {.innales de
Cliiinie ct de Physiipie, vol. 27, 1892), in which the mechanical
equivalent of heat is meaaured directly by what seems a very
excellently devised series of experiments. Its result is
41S57 X 10'.

In order to compare Miculescu's value with that of others,
we must apply a temperature correction which is somewhat
doubtful ; but taking the mean of Rowland's and Griffiths'
values as the most probable at present, we obtain at 15' the
following table : —

Equivalent in foot-pounds at Greenwich at 15° referred to the
"Paris" Nitrogen Thermometer.

Joule. Rowland. Miculescu. Griffiths. ^'cannon!"''

775 778'3 7766 780-2 779-7

If we remember that Rowland's number referred to the
"Paris" nitri'gen thermometer would probably be smaller by
one unit, we are struck with the fair agreement there is, on the
one hand, between the results of Joule, Kowland, and Miculescu,
and on the other hand between Grilliihs and ourselves.

As far as we can draw any conclusions from the comparison,
it seems to point to a difference in the value obtained by the
electrical and direct methods. Whether this difference is due
to some remaining error in the electrical units, or to some
undiscovered flaw in the method adopted by Mr. Griffiths and
ourselve-, remains to be decided by further investigation.

Linnean Society, December 6. — Mr. C. U. Clarke, F.R.S.,
President, in the chair. — .Mr. E. M. Holmes exhibited and
made remarks upon a small collection of Japanese marine alga;,
some of which were of considerable rarity in European collec-
tions.— Prof. D. Campbell brought forward some illustrations
of the relations of vascular crypioganis, as tleiluced from their
development. His remarks, which were li-.lened to with great
attention, gave rise to an interesting discussion, in which Prof.
Bower, Dr. D. H. Scott, Mr. Carruthers, and Prof. Marshall
Ward took part. — "A new revision of the DipUrocarfe^r," was
the title of a paper by .Sir Dietrich Hrandi>, K.C.l.E, who
gave an excellent account of this ordir of forest trees, their
structure and mode of growth, together with a survey of the
literature relating to them, and a clear expo.iiion of his views
concerning clasMfication. He pointed out ihat the order
Dipterucarpeif consists almost entirely of large trees which do
not llower until they have attained a great si/e, wiih a spread-
ing crown on a branchless stem often more than 100 feet high.
Hence it is difficult to obtain complete spccimcr.s in llower .ind
fruit ; and this explains why a lirge piopuriiun of the genera
and species have only of late year- became iiccuiatcly known.
Iv irthals in 1840 knew 34 species; A. .le Caiidolle in 1868
de cribcd 126; Mr. Thiselton Kjcrin 1874 e-tiii.aitd the order
at 170. Sir D. Urandis now consuler-. tnai there ate 320 well-

December 27, 1894]

NATURE

2'5

ascertained species, belonging to sixteen genera, omitting the
genera A)uislroeladus and Lophita, which he regards as jastly
excluded from the order. Notable species are the Sil tree of
India \Sliorea lohista), great forests of which extend along the
foot of the Himalayas and in Central India, the Eng tree
{^Diptcrccarpus hil'iyciilaltis) of similar growth in Burma, and
others found in Cochin China and Borneo. In the discussion
which followed, an extended ctitici?m was oftered by Mr.
Thiselton Dyer, who had paid special attention to this order of
trees, and who, admitting the soundness of the author's views,
considered his exposition of ihem most valuable. The paper
was illustrated by lantern-slides showing the chief peculiarities
of structure in the flowers and fruit.

Royal Meteorological Society, December 19. — Mr. R.
Inwards, President, in the chair. — Mr. II. Southall read a paper
on floods in the West Midlands, in which he gave an interesting
account of the great floods which have occurred in the rivers
Severn, Wye, Usk, and .Vvon. lie has collected a valuable
record of the floods on the Wye at Ross, which he arranges
in three classes, viz. (l) primaiy or highest of all, those of
14 feet 6 inches and above ; (2) secondary, those with a height
of 12 to I4.\ feet ; and (3) teitiary, those «ith a height of 10 to
12 feet. The dales of the floods above 14 feet 6 inches are as
follows: 1770, November 16 and 18 ; 1795, February tl and
12; 1809, January 27; 1S24, November 24; 183:, February
10 ; 1852, February 8 and November 12. The height of the
recent flood on November 15, 1894, was 14 feet 3 inches, which
was higher than any flood since November 1852. The flood on
the Avon at Bath on November 15, 1S94, is believed to have
been the highest on record. — Mr. R. H. Scott, F.R.S., gave
an account of the proceedings of the International Meteoro-
logical Committee at Upsala in August last, with special refer-
ence to their recommendations on the classification of clouds
and the issue of a cloud atlas (see Nature, December 20). —
.\ paper by -Mr. S. C. Knott was also read, giving the results
of meteorological observations made at Mojanga, Madagascar,
during 1892 lo 1894.

Edinburgh.

Royal Society, November 27. — Prof. Copeland, Astro-
nomer-Royal for Scotland, Vice-President, in the chair. —
Prof. M'Kendrick read a paper on observations with the
phonograph, with experimental illustrations. He has devoted
great atttniion to the development of the instrument. He
uses very large conical metallic resonators, and has succeeded
largely in getting rid of the nasal sound of the instrument, so
that part-songs and concerted instrumental pieces can be
reproduced with considerable accuracy, and can be made
audible throughout a very large room. He exhibited, by means of
a lantern, a large number of photographs of the surface of the
wax drum, pointing out the peculiariiies of the record
corresponding to various qualities of instrumental or vocal
notes and chords.

December 3. — Prof. Geikie, Vice-President, in the chair.
— Dr. John Smith communicated notes on a peculiarity it
the form of the mammalian tooth. Roughly speaking, the
general appearance of the mammalian tooth is that of a cone,
flattened to some extent, and twisted about its axis to a greater
or less degree, and then bent so as to form a port ion of a circle.
If this bending takes place to a large extent, it is not easy to
recognise the axial twist. The author showed that the charac-
teristic is always present, being easily seen in the strong
spiral of the narwhal's tusk, or the remarkably twisted teeth of
the Meioploilon described by Sir William Turner in the Reports
of the Challenger expedition, and being almost unrecognisable
in the human tooth. The axis of the twist is directed back-
wards and inwards from the face of the tooth, and it is this
characteristic which enables dentists to distinguish teeth from
each side of the mouth. — Mr. Gregg Wilson read a paper on
the development of the Miillerian duct of amphibians.
He contends that this duct does not arise from splitting of the
segmental duct, but is developed in the same way as the
Miillerian duct of the higher mammals. — Dr. George Hay,
Pittsburg, submitted an account of a new method of correcting
courses at sea. His apparatus consists of two superposed
compass cards, whose north points are set at an angular
distance apart which is i qiial to the magnetic variation. The
true course being read oft on one, the corresponding point of
the other gives the compass course. Simple as this arrange,
ment is, Dr. Hay asserts that he has never known it to bg

employed at sea. — Prof. Tait read a note on the constitution
of volatile liquids. His equation, deduced from the graph of
the Cliallenger results, applies with great accuracy to non-
volatile liquids, such as water, at ordinary temperatures and
at pressures up to 3000 atmospheres. It does not apply
with quite so great accuracy at the lower pressures to such
liquids at or near their boiling points, and it is still less
accurate in this respect when applied to volatile liquids.
Prof. Tait suggests that this may be due to the existence,
in the liquid, of dissolved gases or of vapour. — Prof. Tait
also read a note on the isothermals of ethylene." His
equation enables one to calculate, with great accuracy, the
pressure, at a given temperature and volume, in the neighbour-
hood of the critical point, from Amagal's observations ; but the
volume, at a temperatu-e and pressure in the neighbourhood of
the critical point, given by .Vmagat's observations, cannot be
calculated, with any approach to accuracy, from the equation.
This is due to the excessive rapidity with wh'ch the diflerence
of the volumes in the liquid and vapourous states diminishes with
increase of temperature as the critical point is approximated to.

Paris.

Academy of Sciences, December 17. — Annual public
meeting. — M. Maurice I o-wy in the chair. — The proceedings
were commenced by an address, delivered by the President.
The past year was referred to as a period of slow growth and
con>olidation of knowledge rather than as being characterised
by any very brilliant discoveries. The members and associates
deceased during the year — MM. Edmond Fremy, Brown-
Sequard, Mallard, Duchartre, Ferdinand de Le5sep~, General
Fave, MM. Hermann von Helmholiz and P. Tcehbichef —
were referred to appreciatively, and their influence on the pro-
gress of science pointed out. The system of prizes given by the
Academy was referred to at the conclusion of the address, which
was followed by the reading of the awards by M. Berthelo*. In
Geometry the grand prize for the mathematical sciences was
awarded to Dr. Julius Weingarten ; honourable mention was
accorded to M. C. Guichard. The Bordin prize was adjudged
to M. Paul Painlevc'( Analytical Mechanics), MM. Liouville and
Elliot receiving honourable mention. The Francoeur prize was
obtained by M. J. Collet ; the Poncelet prize by M. H. Laurent,
for his mathematical works. In Mechanics the extraordinary
prize of 6coo francs was awarded to (i) M. Lebbond (2000
fr.), for his works on electricity ; (2) Commandant Gossot (2000
fr.). for the determination of the velocity of projectiles by means
of sound phenomena ; (3) Commandant Jacob (i50ofr. ), for his
study of the ballistic effects of the new powders ; (4) M.
Souillagouet (500 fr.), for his ." Recueil de Tables du point
auxiliaire." The Montyon prize fell to M. Bertrand de
Fontvioland, for his works on the resistance of materials. The
Plumey prize was equally divided between M. .\nd'e Le
Chaielier and M. J. .\uscher. M. Autonne received the
Dalmont prize (3000 fr. triennially) for his works on rralysis.
In connection with the same prize, M. Maurice d'Ocigne
was awarded a supplementary prize, M. Pochet exceptionally
honourable mention, and M. Willotte very honourable mention.
In Astronomy the LaLande prize was adjudged to M. Javelle
for his researches on nebulcc. The Damoisean prize, for per-
fecting methods of calculation of pertui bations of minor planets,
went to M. Brendel. The Valz prize was awarded to M.
Coniel for work on small planets, and the Janssen prize to
Prof. George Hale (soLir photographic observation ). In
Statistics the Montyon prize was adjudged to M. Boutin, a
supple:nentary prize to Dr. Faidhorbe, and honourable men'ion
to Dr. A. Cartier and Dr. Tastiore. In Chemistry the Jecker
prize was divided between M.M. Barbier, Chabrie, P. .-Vdam,
and Meslans. In Mineralogy and Geology the VaiUant prize was
not awarded, as no memoir had been presented. In Botany the
judges for the Desmazicres prize awarded an "encounagement,"
to M. Sappin-Troufly. The Montagne prize was accorded lo
M. Husnot for his publication on Mosses ; Brother Joseph
Hcribaud received a second prize for his " Dialomaceje of
Auvergne." In Anatomy and Zoology the Thore prize to
M. Cuenot for work on the physiology of insects. The Savigny
prize to M. M.iyerEymar for researches in conchology. The
Da Gama Machado prize was reserved, although the Commis-
sion gave high praise to work submitted by Dr. L. Phisalix
and M. L. Joubin. In Medicine and Surgery the Montyon
prize to (l) M. Felizet for a treatise on "inguinal hernia of
infancy, (2) M. Laborde for his work on " the physiological

NO.

13 13, VOL. 51]

216

NATURE

[December 27, 1894

treatment of the dead body," (3) M. Panas for his treatise on
"affections of the eyes." Meniions and minor awards went
to MM. Legendre, Broca, Vacquez, Vaudremcr, Marcel
Baudouin, Ferreira, Ernest Martin, Pietra Santa, Voisin,
and Petit. The Barbier prize was awarded to Prof.
Henri Leioir for his work on scrofulo-tuberculosis,
Drs. Ariault and Tscherning receiving honourable mention.
The Brcant prize was adjudged to M. Arloing for his work on
the bacillus of peripneumonia in cattle : the Godard prize was
accorded to MM. Melville- Wassermann and Nuc! Kalle ; the
Parkin prize to MM. Behal and Choay : the Hellion prize
between Dr. Lardier and MM. Bsni-Barde and Malerne, Dr.
Kenon receiving honourable mention : the Mege prize to M.
Faure ; the Lallemand prize to M. Gley, honourable mention
to MM. Nabias and P. Janet. — In Physiology, the Montyon
was divided between MM. Phisalix and Bertrand and M.
Raphael Dubois, honourable mention being given to MM.
Morot, Blanc, and Philippon : the Pourat prize fell to M.
Haufmann, a mention being accorded to M. Thiroloix. In
Physical Geography, the Gay prize was awarded to M. Mattel.
General prize- — The Montyon pi /e (unhealthy industries) was
divided between MM. Balland and Lavet ; the Cuvier prize was
awarded to Mr. John Murray of the C/;(7//t'«^tTexpedition : the
Trtmont prize was .iccorded to M. Emile Riviere ; the Gegner
prize to M. Paul Serret ; the Delalande-Guerineau prize to the
Marquis de Kolin : the Jerome Ponti prize to Commandant
DefTorges ; the Tchihaichef prize to M. Pavie ; the Houllevigue
prize to M. Bigourdan : the Cahours prize (i) to M. Varet and
(2) M. Freundler ; the Saintour prize to MM. L Deburaux and
M. Dibos ; the Laplace prize to M. K louard Glasser ; and the
Rivot prize to M.M. Glasser, Leprince-Ringuet, Henri Parent,
and Le Gavrian. The programme of prizes for 1S95, 1896,
1897, and 189S is given in detail so far as yet decided.

Beri.i.n.

Physiological Society, November 23.— Prof, du Bois
Reymond, President, in the chair.— Prof. Zuntz gave an
account of his researches on the measurement of the
amount of blood in circulation and the work done by
the heart. For the horse he found 71 to 72 c.c. of
blood per kilo body-weight per second ; for the dog, as
based on the consumption of oxygen, 78 c.c. These values do
not correspond lo the marked difference in size of the animals,
but may be explained as due to the fact that the dog was experi-
mented upon while fasting and at rest, whereas the horse was
not. For a horse in complete rest the value obtained was 50
c.c. For man he estimated the value at 60 c.c. Blood-
pressure falls but slightly along the arterial system, and was
found lo be nearly (he same in the carotid and in a small branch
of the facial artery. The work done by the human heart he
calculated as amounting 10 about 20,coo kilogram-metres in the
twenty-four hours. When the body is working the work done
by the heart increases also, so that in the case of the horse the
blood pumped out now amounted to 600 c.c. per kilo per second,
or twelve times as much as during rest. The frequency of the
pulse could by work be increased fourfold, and the work done
by the heart to thrice its normal amount. — Dr. Cohnstein had
carried out further experiments on the transudation of solu-
tions of sails into distilled water, and using mixtures of salts as
well as mixtures of colloids and crystalloids, he had observed
that an increased transudation of the solids follows upon an
increase of external pressure. He applied these results to
explain Ihe mode of formation of lymph, which he attributed
10 transudation as well as to filtralion, ihus opposing
lleidenhain's view thai it is due to a distinct secretion. He ex-
plained the action of lymphagogues, on Ihe basis of his own
experiments, as due to Ihe power these substances possess, when
mixed with an albuminous fluid, of confining the diffusion of Ihe
external fluid entirely towards the interior of the tube which
contains them in solution.

Amstkrdam.
Academy of Sciences, November 24. — Prof. Van de
.Sande liakhuyzen in ihe chair. — Prof. J. .\. C. Oudemans
communicated the results obtained in solving two problems, an
atlronomical and a geodelical one, namely :— (1) In how long a
period do tlari, the velocities of which in the line of vision are
known, lose or gain 01 magnitude? {.See "Our Astronomical
Column," December 13, p. 160). — Dr. Van Romburgh (IJuiten-

zorg) has examined the essential oils of Polygala variahilis,
H. B. K., B. albifloia, F.'lygahi oUiJ'cra, lleckel, and Po'y^il.r
Javana, and found them to be nearly all methylsalicylate. —
Mr. Jan de Vries : on a group of plane curves. This paper
contains some theorems on plane curves {/> of the {n -f w)*'i order,
: with m"- double points, (A), forming the base of a pencil of
curves of the ot' degree.

DIARY OF SOCIETIES.

London.
THURSDA K, December =7.
RoVAl. Institution, at 3. — The Manufacture of an Electric Current:
Prof. J. A. Fleming, F.R.S.

FRIDAY, December 2S.
RoYAi. Geographical Societv, at 4. — Holiday Geography : Dr. H. R.
Mill.

SATURDAY, December 23.
Royal Institution, at 3. — The Current Working of a Chemist: Prof.
J. A. Fleming, F.R.S.

SUMDAY, December 30.
SfNDAV Lecture Societv, at 4. — The Action of Light on Bacteria an:!
Fungi : Prof. Marshall W.ird, F.R.S.

TUESDAY, January i, 1895.
RoVAL Institution, at 3. — The Workipg of an Klectric Current: Prof. J.
A. Fleming, F.R.S.

THURSDAY, January 3.
Royal Institution, at 3. — The Working of an Electric Current : Prof. J.
A. Fleming, F.R.S.

SATURDAY, January 5.
Royal Institution, at 3. — The Working of an Electric Current : Prof. J.
.'\. Fleming, F.R.S.

CONTENTS. PAGE

A Standard Treatise on Chemistry. Hy M. M.

Pattison Muir 193

Man- -the Primeval Savage. By Prof. W. Boyd

Dawkins, F.R.S 194

The Sequence of Studies. Hy H. G. Wells .... 195
Our Book Shelf:—

Conway: " Climbing and Exploration in the Kara-

koram- Himalayas" 196

"The Royal Natural History " 197

Munro : " Kitchen Boiler Explosions " 197

Gordon : " The Island of Madeira, for the Invalid

and Naturalist " 19/

Letters to the Editor: —

"Acquired Characters." — Right Hon. Sir Edw.

Fry, F.R.S 197

The Alleged Absoluteness of Motions of Rotation. —

A. E. H. Love, F.R.S 19S

The Anti<|uiiy of the "Finger-Print" Method. —

Kumagusu Minakata ... 199

Peculiarities ol Psychical Research. — Edward T.

Dixon ; Prof. Karl Pearson . . 200
The .\rlilicial .Spectrum Top.— Charles E. Ben-
ham ; Prof. G. D. Liveing, F.R.S 200

"Solute."— F. G. Donnan 200

"The Elements of (,)uaternlons."— Lieut. -Colonel

H. W. L, Hime 201

The Lick Observatory. (IlliislraUil.) By A. Fowler 201
Studies of a Growing Atoll. By Dr. Hugh Robert

Mill 203

Notes (Illuslrated) 205

Our Astronomical Column : —

Advances in Lunar Photography • . . 207

Comelary K.phemerides 207

Russian Aslroo'inical Observations 207

On a Remaikable Earthquake Disturbance observed
at Strassburg, Nicolaiew, and Birmingham, on
June 3, 1893 (IthislraieJ.) By C. Davison ; Dr.

E. von Rebeur Paschwitz 208

Explosions in Mines 211

The PobS'bilities of Long-Range Weather Fore-
casts. By Piof. Cleveland Abbe 212

Scientific Serial 2'3

Societies and Academies 214

Diary of Societies 216

NO. 131;,. VOL. 51]

NA TURE

217

THURSDAY, JANUARY 3, 1S95.

BIOLOGICAL LECTURES AND ADDRESSES.
Biological Lectures and Addresses delivered by the late

Arthur Milnes Marshall, M.A., M.D , D.Sc, F.R.S.

Edited by C. F. Marshall, M.D., B.Sc, F.R.C.S.

(London : Nutt, 1S94.)

ANY of us remember the pleasure experienced in
listening to the vigorous addresses of Prof.
Milnes Marshall, whose sudden death, about a year
ago, was such a blow to biologists and to all interested
in the spread of scientific education. In reading them
now, the energy and humour of the speaker are ever
present in the memory, giving life to the apt illustrations
and clearly expressed thoughts.

The choice of appropriate subjects for the occasion of
these addresses shows remarkable discrimination. It is
quite clear that the late Prof. Milnes Marshall believed
that a single address— if heard at the right point in his
career, and delivered with the confidence of this belief —
might change the whole attitude of mind with which a
student approached his subject.

Lecturing to the Owens College Medical Students'
Debating Society, he chose as his subject '" Embryology
as an aid to .Anatomy." In preparing to address a class
of students expected to deal with, and to remember, in
the course of their daily work, innumerable details which
are as yet far from receiving a scientific interpretation,
he selected embryology, which " offers an explanation of
many otherwise completely unintelligible anatomical
facts"; and by the example of the development of the
nerves supplying the muscles of the eye, the thoughts of
many young anatomists may well have been turned into
a direction which was of the most inestimable benefit to
their study.

Equal wisdom and foresight were shown in th<; selec-
tion of subjects for addresses to the Members of the
Manchester Microscopical Society, viz. "Inheritance"
(1888), "The Shapes and Sizes of Animals" (1889),
"Some Recent Developments of the Cell Theory"
(1890), and "Death" (1893). In the choice of these
subjects, and in their treatment, the Members of the
Society are shown that the most profound biological
problems are to be approached and, perhaps, solved by
the study of the most minute detail and the lowest forms
of life. The student thus made fully aware of the
dignity and possibilities of his subject, will not be likely
to forget, in the patient investigation of histological or
biological detail, the wide issues which are at stake.

The subjects chosen for presentation to other audiences
are just as happv. Sometimes, as in "The Theory of
Change of Function," a difficulty in evolution by natural
selection is taken as the subject, and the final solution
given in the clearest and simplest manner. It would be
well if this address were widely known, for the difficulty
it deals with is still frequently raised, just as if no
explanation had ever been forthcoming. In other cases,
wide questions, such as "The Influence of Environ-
ment" or "Animal Pedigrees," form the subjects of the
addresses.

NO. 1314, VOL. 51]

The addresses abound in humorous and apt illustra-
tions. Thus, on p. 39, in order " to show that, even in
our worldly transactions, changes of environment often
produce not only direct and immediate changes and re-
adjustments, but also definite and calculable ones," he
gives as an example the following : — " Let (z be a mer-
chant, and /> his purse : the combination ab will at once
strike you as a natural and stable one. . . . Now let c
be a highwayman, and d his pistol : the combination cd
is again recognised as a natural and stable one. Now,
bring the compound ab into the presence of the com-
pound cd, and mark how the stability of the former is
shaken. . . . The several elements become rearranged
in a manner that finds perfect expression in the formula —
ab -{-cd = a -{-bed."

Again, in order to illustrate the tendency towards re-
version to an ancestral condition, the card house is
selected —

" The resulting structure is a far more imposing one
than the pack of cards when laid flat on the table, but it
is also an eminently unstable one, its instabilitv being
directly proportional to the extent to which it departs
from its initial condition." (p. 104.)

"The influence of food yolk on development" is com-
pared to "that of capital in human undertakings"
(p. 224), the metaphor being worked out in an interesting
and amusing manner. Prof. Weismann's views on the
absence of death in Protozoa are illustrated on p. 273 as
follows : —

" If the original Amceba be called Tom, and the pro-
ducts of fission Dick and Harry, the upshot of the
process may be expressed by saying that Tom has dis-
appeared without having died, while Dick and Harry
have come into existence without having been born.
Nothing has died, there is no corpse to bury, and our
ordinary ideas with rejjard to individuality and identitv
fail altogether to afford answer to the question — Where
is Tom at the end of the process .' "

There are a few sentences in the addresses which
are perhaps capable of misconstruction. Prof. Milnes
Marshall appears to have hesitated to accept the belief in
the hereditary transmission of acquired characters, and
)et there are some statements which seem to imply this
belief. This is the case with the statements that the
white man and the negro have been evolved " through the
long-continued action of selection and environment"
(pp. 247 and 358), that modifications of development
have occurred "due chiefly to mechanical causes '
(p. 316), that the "larger size of the eggs of fresh-water
forms appears to be dependent on the nature of the
environment" (p. 313), although in this case it is clearly
shown on the following page that environment is believed
to act selectively and not directly.

The term "acquired character" is made to bear still
further burdens in the way of special interpretations. It
was unfortunate so late as 1S90 to continue to speak
of the distinction in development " between those
characters which are really historical and inherited, and
those which are acquired or spurious additions to the
record "(p. 307), or to speak of the view that Amphioxus
and the Cyclostomes are "degenerate animals— whose
simplicity is acquired a.n A deceptive rather than real and
ancestral." (p. 335.)

2l8

NATURE

[January 3, 189-

The book is well and clearly printed, and has been
extremely well edited. The only printer's error noted
was in the title of Mr. Oldfield Thomas' paper on p. 31 8.

E. B. P.

TEXT- BOOK OF AGRICULTURE.
Advanced Agriculture. By H. J. Webb, Ph.D., B.Sc.
(Lond.). Svo., pp. vi. and 672. (London : Longmans,
Green, and Co., 1S94.)

TEXT-BOOKS of agriculture are rapidly increasing
in number. The name of the author on the
title-page of this is that of the late Principal of
the Agricultural College at Aspatria, Cumberland, who,
most unfortunately, was unable ti conplete the work.
He was struck down at a comparatively early age, and
in the midst of hard work and a successful career. He
is most highly spoken of, and deservedly so, in the pre-
face by the editor of the book, Mr. J. Lister, of Aspatria.
From such hands we anticipated much and good work,
though the task might appear heavy. We regret to say
that we have been greatly disappointed.
We are told that—

'•This work, though primarily intended for the advanced
stage of the Science and Art Uepartmenls' E.xamination
in Principles of Agriculture, will also cover the greater
part of the syllabus of the Honours stage. Care has,
however, been taken not to adhere too rigidly to the
syllabus in question, and we trust it may be found
equally serviceable for the examination for the diploma
in Agriculture of the Highland and Agricultural Society
in Scotland, and the senior examination of the Royal
Agricultural Society of England."

Even the fact that the book has been prepared mainly
to assist students to pass examinations, can hardly excuse
some of the statements we meet with. In agricultural
geology we are told, among other scraps of information
that zeolites are " hydrated silicates of alumina or lime."
This IS scarcely true. " Diorite consists of plagioclase
and hornblende." This is tiue, but as the meaning of
plagioclase is nowhere explained, it does not help the
student much. In agricultural physics we learn that "a
heavy soil might contain absolutely double the amount of
phosphoric that a light soil did, although it would show
only the same percentage if it were twice as heavy."
We have tried to believe this, but till now we do not
understand it. In engineering, a definition of horse-
power is given without any mention or suggestion of
time as a possible factor.

In chemistry, Rendonda[Rcdonda] and Alta Vela phos-
phates arc said to contain a large quantity of alum;
leather to contain 4^ to 9 per cent, of ammonia, and meat-
meal and meat-guano to contain much ammonia. This is
the more confusing, as in other manures, mentioned on the
same page, the percentage of nitrogen is correctly given •
but this confusion of ammonia with the ammonia equiva-
lent of the contained nitrogen is common throughout.
Ammonium chloride is said to contain about 18.', per cent,
of water and 321I, per cent, of ammonia. The formula of
monocalcic phosphate is correctly given as CaH,P.^Og,
and tricalcic phosphate as Ca^P^O,, and, yet, in one
analysis iS'oi per cent, of the former is said to be equal to
2%\ per cent, of the latter, and in another case \yi per
NO. I 314, VOL, 51]

cent, of monocalcic phosphate is said to be equal to
3007 per cent, of tricalcic phosphate made soluble : of
course the so-called monocalcic phosphate in these
analyses is calcium nietaphosphate, formerly known as
" biphosphate'' : but how can tlie student know this.^
Cellulose is described as a white amorphous powder.

In agricultur.-,l botany, we are told that "protoplasm
generally presents itself as a granular semi-fluid sub-
stance with or without a cell-wall." " The corolla, when
present, usually consists of green leaves or sepals, some-
times scarcely noticeable " This later statement is, of
course, only a misprint : but it is also only an example of
several similar serious misprints.

The root residues of crops remaining in the soil are
said to " consist very largely of protoplasm." The
section on farm crops, however, in which this occurs, is
written in a curious style, somewhat dilticult to follow.

On looking up information regarding anthrax, we find
that "although a disease of the blood, the writer [in
this case Mr. H. Thompson] considers it more of a
dietetic nature, having seen it produced from steeped
brewers' grains allowed to stand till they had reached the
acetous stage of fermentation. It is also produced by the
hay bacillus, obtained from the fermentation of chopped
hay and from mouldy cotton-cakes, more particularly the
undecorticated variety. He has also seen it arise in certain
undrained lands. Although very fatal to other animals,
such as dogs, cats, and poultry, that may have eaten
the flesh or blood, yet he considers it neither infectious
nor contagious, having never known it to extend beyond
the buildings in which it originated. Again, the disease
was always traceable to some peculiarity of the feeding,
and the writer thinks that it is analogous to an aggravated
form of red water." And this stuff is set forth as advanced
agriculture. There are several very startling statements
in the chapter on veterinary science ; e.g. in retention of
the fa;tus," different bones belonging to the fcctus, such as
jaw, scapula, ribs, humerus, and several others, are passed
at times through the rectum."

In the chapter on agricultural entomology, we hardly
suppose the author is serious when he recommends the
use of rape-cake, at the rate of two or three tons per
acre, to clear the field of wire-worms.

In part ii. of the book the misstatements are perhaps
not quite so numerous or so serious, but they are not
absent. In the chapter on permanent pastures, after a
notice of the power which leguminous plants, with the
aid of the low organisms present in the nodules on their
roots, possess of appropriating free nitrogen, we are
told that "this fact of the nitrogen-storing power of the
leguminous plants explains the action of heavy dressings
of nitrogenous manures on permanent pastures encourag-
ing the growth of grasses, especially the coarser ones, at
the expense of the clovers." We fancy that this explana-
tion of the fact will not satisfy many readers.

The work of Rothamsted is frequently referred to and
fully appreciated ; but why should Rolhamslcd be spelt
in three different ways in the book ■■ l'iob:ibly, however,
every would-be advanced agriculturist knows that there
are not three Rolhamsteds.

But we have given enough instances of what are very
serious flaws in the book. Much of the matter is exceed-
ingly good and useful ; but does not this really add to the

January 3, 1895]

NATURE

219

danger of the work in the hands of the learner who is
not in a position to sift the wheat from the chaff and the
weeds ?

We do not think that this book will serve to advance
the reputation of its author, nor to advance agriculture.
We submit that " advanced agriculture" is not agricul-
ture plus a smattering of chemistry, a dip into geology, a
pinch of botany, a skim of entomology, a sniff at meteor-
ology, and so on ; even if the sciences be correctly ex-
pounded. The text-book of agriculture, like that of other
subjects, has no doubt to pass through stages of evolution,
and we trust it will not long remain at the stage indicated
by this book.

EWING ON THE STEAM ENGINE.

The Steam Engine and other Heat Engines. By
Prof. J. A. Ewing, M.A., B.Sc, F.R.S., M.Inst.C.E.
(Cambridge : The University Press, 1894.)

ENGINEERING students and others will welcome
the present volume as one likely to increase their
knowledge of an important branch of engineering, from
the pen of an acknowledged master of the science ;
any work by Prof. P2wing is sure to be read by engineers
generally, and treated as a book for constant reference.

As is well known, Prof. Ewing wrote some valuable
articles for the " Encyclop;tdia Britannica " on this sub-
ject, and it is an expansion of these articles which consti-
tutes the basis of this work. As a University text-book
this volume will fill a great want, treating as it does,
from the theoretical side, a subject only descriptively
dealt with in the majority of such text-books. As
the author remarks ; " The endeavour throughout has
been to make evident the bearing of theory on practical
issues."

The first six chapters may be said to contain the early
history of the steam engine, and a scientific treatment of
the general behaviour of steam in the cylinder, as well as
the general theory of heat engines. The information
thus brought together is of a valuable nature, and the
references which are made, add considerably to the
usefulness of the work. To the thoughtful practical
engineer, this portion of the book will form a perfect
mine of matter for careful consideration.

The testing of steam engines has of late years become
a common occurrence, thanks to Profs. Kennedy,
Osborne Reynolds, and many others. Designers and
manufacturers of such engines have everything to gain
by such experiments ; few being, like the late Mr.
Willans, capable of carrying out scientifically accurate
trials of their own engines. Chapter vi. deals with this
important question. Many useful hints are given, and
sources of error carefully pointed out. As indicator
diagrams play such an "important part in the trials of
steam engines, it is interesting to note that the Crosby
Company's modified form of Richards' Indicator is con-
sidered by Prof. Ewing to be one of the best.

Compound expansion comes in for very full and accu-
rate treatment ; many sets of indicator diagrams are ex-
plained and illustrated, and the difficult matter involved
in the combination of such diagrams is lucidly dealt
with. Of the advantages of compound expansion in the
NO. 13 14, VOL. 51]

use of high-pressure steam, we are told much, and also of
the mechanical advantages of such an arrangement. We
cannot help pointing out that, in this matter, the practical
men on the Clyde were singing the praises of compound
engines before the theoretical men would admit of their
utility or economy. On valves and valve gears our
author has much to say, although we notice nothing re-
markable in the chapter. Locomotive engineers do not
trust entirely to the drawing-board or calculation in the
design of valve gears. It is now the practice to try the
proposed gear as a full-size model on the valve gear
testing machine, and so to obtain the best results. The
latest machine of this kind has been erected in the
drawing-office of Messrs. Sharp, Stewart, and Co., the
eminent locomotive engineers, of Glasgow. The saving of
time is great, and very accurate results are obtained. In
fact, in such drawing-offices, the old valve diagrams, with
their many curves, are things of the past, and a simple
table of leads, cut-offs, suppressions, &c., for the different
degrees of expansions, has taken their places.

Chapter ix. treats of the many forms of governors
used for regulating the work done in the steam engine,
commencing with Watt's simple arrangement, and finish-
ing with the differential or dynamometric governors in-
vented by the late Sir W. Siemens ; and further on in the
book we find much useful information concerning the
work on the crank shaft. Diagrams of crank efforts are
given, and the effect of friction and of the inertia of the
reciprocating pieces are duly discussed. The balancing
of machinery is an all-important subject, in fact the life
of any machine depends upon the balancing of its
moving parts ; for this reason, we are sorry to see
that Prof. Ewing has so little to say on this subject
generally, and particularly on the balancing of loco-
motives. If theory is of any help to the locomotive
engineer at all, surely it could be best applied in
balancing ; some engineers balance the whole reciprocat-
ing weight, others none ; the majority about 30 per cent.:
which is right ? Prof. Ewing does not help us, but
observes that " the final adjustment of the balancing
masses is usually a matter of experiment, the locomotive
being hung in chains to allow its oscillation to be
observed " ; this, to say the least of it, is never done in
this or any other country.

The production of steam is the subject treated in the
following chapter ; the illustrations of the different boilers,
with the descriptions, are e.xcellent. The only specimens
of water-tube boilers illustrated are the Thornycroft and
the Babcock and Wilcox, the latter used principally for
stationary engines. The Thornycroft boiler is the fore-
runner of similar types ; for instance, the Yarrow and the
Clyde among others, all of which are considerably
lighter than the ordinary marine boiler. As an example
of the locomotive boiler, one of the London and North-
western Railway Company is taken as typical of British
practice. As an example of an injector for feeding
boilers, an old-fashioned type of Giffard injector is
illustrated, but more recent types arc described.
Mechanical stoking and the use of liquid fuel are also
mentioned.

The following chapters, conclude the work, occupying
some sixty pages with descriptions of forms of steam
engines, air, gas, and oil engines. The Willan's central

2 20

lYA TURE

[January 3, 1895

valve engine is well illustrated, and the description does
credit to what is probably the most economical steam
engine ever designed. A description is given of rotary
engines, but none are illustrated. The " Rota ' engine,
designed and made by MacEwan Ross, of Glasgow,
might have been included with advantage. The loco-
motive is outlined, and the compound type described ; but
no information as to tests is given, probably because no
trustworthy data can be obtained ; and as no British Rail-
way Company, with one possible exception, is likely to build
any more compound engines, it seems probable they are
not the unqualified success they were originally claimed to
be, although the Vauclain system, with four outside cylin-
ders, appears to be a success in the States. But it must
not be forgotten that the .American rival is a very un-
economical engine when compared with our own.

N. J. L.

OUR BOOK SHELF.

Das Verhdllniss licr Philo.wphie su dcr empirischen
Wissenschaft von der Xalur. By David Wetterhan.
(Leipzig : \V. Engelmann, 1894.)

This is the essay which gained the prize of 1000 marks
offered, in 1891, by the Philosophical -Society of Berlin.
It consists of 1 10 pp., of which about twenty are occu-
pied by notes and abstracts from various writers, in small
print.

Naturally, in giving forth his own views, some of which
possess considerable originality, the author makes con-
tinu.il and extensive use of ihe theories of Kant, Schopen-
hauer, Wundt, Bunge, and others ; and one noticeable
feature about the work is the full share of recognition
accorded to English philosophers and scientists, such as
Faraday, Herbert Spencer, Danvin, Romanes, and
Huxley. The writer well remarks that the limits of
scieniific knowledge are everywhere and nowhere.

In the earlier pages the author discusses the relation
between the physical and the psychical sides of nature.
The theory of the conservation of energy has nothing to do
with mental processes : it governs the quantitative rela-
tions of all processes of nature, but does not explain
their qualitttive differences. Sensation, consciousness,
motor impulse, are not forms of energy, and do not corre-
spond to them, but to the causes of qualitative changes
in forms of energy.

The world of psychics cannot be separated from that
of physic-, and we must look forward to the future pro-
gress in the latter science to bring the qu ilitative changes
into connection with the theory of the conservation of
energy. The author shows by a very simple example —
" .Shall I kill that spider, or leave it alone .' " — the effect of
his will on surrounding nature ; and the divergent
effects thereon which ivould result from each of the wo
altcrnaiive modes of procedure.

Memory he believes to be caused by an impulse of a 1
certain kind, producing in the particular arrangement
of the sm.il e>t particles in the ganglion cells and nerve
fibres a modification in the s.iine directinn as was pro- |
duced by the original impulse, and resulting in corre-
sponding physical phenomena. But he acknowledges
that, at pre* nt, we cannot explain " brain oscillations."

The principle of evolution sheds a light upon the
psycho-physical problem : physical development is not
the cause but the etfect of psychical dcvelDpment, and
the molific^tions in ihe brain and nervous system
through'iui the animal kingdom are intelligible as result-
ing from psychical causes, whereas the physical causes, if

NO. I 3 14. VOL. 51]

they exist, remain hidden. He considers that even in
paleontology we can detect traces of this psycho-physical
process by the examination and comparison of the cranial
capacity of the skulls of extinct reptiles and mammals.
As man is the culminating point in mental development
amongst mammals, so is the ant amongst insects ; but
clearly this position has in each case been attained
independently, and is independent of the structure
of the nervous system. The inheritance of ac-
quired characters is discussed, and the old difficulties
presented by a disbelief in it are once more brought
forward ; and especially the difficulty in the adapta-
tion of terrestrial mammals to a life in water, such
as must have occurred in the ancestors of the Cetacea.
The author endeavours to show that the principle of pro-
gressive psycho-physical development may admit of a
vital-mechanical explanation, if the transference of
acquired characters, as a consequence of changed
functions, is possible for " keimplasma. '

The author is apparently a practical man of science, and
not a mere arm-chair philosopher; he fully recognises that
philosophy must be based upon scientific experiments,
and quotes Huxley's words, '' fhe Laboratory is the fore-
court of the temple of Philosophy."

Meteorology, Practical and Applied. By John William
Moore, B.A., M.D., M.Ch., F.R.C.P.l. (London:
F. I. Rebman, 1894.)

It is to be hoped that this little book may meet with the
popularity it deserves. Well written and well illustrated,
it ought to recommend itself to that numerous class of
whom some knowledge of meteorology is now required.
The author, a medical practiiioner, has evidently, nrst of
all, but by no means exclu-iveh, sought to interest
medical otticers of health and those who seek a qualifi-
cation in preventive medicine and its allied b anches.
Writing for such students, the author has prudently not
burdened his work with technical terms, or attempted to
discuss with any completeness the geneial motions of
the atmosphere depending upon the application of
thermodynamics. Neither does he fall entiiely into the
popular and pleasing style of writing; though he does
seek legitimate inierest by exhibiting the many points
in which meteorological inquiry bears on social and
sanitary science, how it may benctii the agriculturist,
protect the traveller, or instruct the physician.

The book is divided into four sections. In the fust we
find a very full and, consideiing the source Irom which
it is drawn, probably accurate account of the hisiory and
development of the United States Weather Bureau It
seems to have occurred to the author, that if he shows to the
reader at an early stage the inierest and devotion which
the shrewd American gives to this subject, he will con-
vince him that there is something in meteorology after all,
beyond the dre.iry and wearisome accumulation of baro-
meter and thermometer readings. Then we have, of
course, the description of the necessary instruments in
use, with their corrections. We are glad to see in this
section due prominence given to Mr. Aitken's iiiieresting
work on atmospheric dust ; and in the chapter on evap-
oration we notice that Mr. Apjohn's fornuil.x are given
correcilv, which is not the case in some other «ell-known
elementary works. The third section of ihe book ireats
of climate and weather, a section that might wiih advan-
tage have been made fuller ; but in reviewing the whole
subject of meteorology wiihin moderate compass, it is
necessary to curtail somewhere. The last section con-
siders the influence of season and weather on disease.
Here the author is apparently on very familiar grourid,
and the small space rievoied 10 this tope is full of in-
terest and suggestion. There are one or two slips in the
text, as, for instance, on page 10, where the oft-repeated

January 3, 1895]

NA TURE

221

error is once again seen, of mistaking the axis of rotation
of the earlh for the plane of the equator ; but such over-
sights are easily excused in presence of the collection
of a large number of facts, well arranged and tersely
expressed. W. E. P.

The Province of South Australia. By J. D. Woods,
J. P. With a Sketch of the Northern Territory, by H.D.
Wilson. Pp. 446. (Adelaide : C. E. Bristo'w, 1894.)

This account of the province of South Australia, from
its discovery to the end of 1S92 was, the preface informs
us, written under the authority ol the Government of the
Colony. It may therefore be taken as an authoritative
work of quite a different and a better kind than the many
descriptions of Australia that have appeared during the
past few years. The physical features, fauna, flora,
climate and meteorology are fully de-cribed, and the
story of the explorations of the interior of the continent is
full of interest. There is a chapter on the agriculture of
South Australia, and one on the minerals in which the
province is so wonderfully rich. Those familiar with the
history of education in .South Australia will remember
that prior to 1874 the colony did not possess a university.
It was in 1S72 that an endowment of ^20,00'-', given by
.Sir W. W. Hughes, was applied to the founding of
two professorships — one for classics and comparative
philology and literature, and the second for English
language and literature and mental and moral philosophy.
Science was benefited shortly afterwards by a like
donation from Sir Thomas Elder, to found a professor-
ship for mathematics and another of natural science.
The same benefactor gave ^10,000 for the establishment
of a medical chair in 1883, and /J 1000 for evening classes ;
and the Hon. J. H. Angas gave /^6ooo for the creation of
a chair of chemistry, and ^4000 for the establishment of
scholarships and exhibitions. Though the Adelaide
University was incorporated in 1874, the present Uni-
versity buildings were not opened until 1882. The
School of Mines and Industries, as it is officially desig-
nated, was opened in 1 889, and has steadily increased in
influence and usefulness since then.

The chapter on the aborigines of South Australia is
perhaps the best in the book, and as the author
has had more than forty years' experience with the
blacks, he writes upon what he is well qualified to de-
scribe. Altogether the volume includes much that has
not hitherto appeared in print in a collected form, and
therefore deserves to rank with the best books on
Australia, its people, and its resources.

Measurement Conversion Diaf^rains. By Robert H.
Smith, Professor of Engineering, i\lason College,
Birmingham. (London: Charles Griffin and Co.,
Limited, 1895.)

The scope of this work is described on the title-page as
follows: — ''Forty-three graphic tables or diagrams for
the conversion of measurements of different units, com-
prising conversions of length, area, volume, weight,
stress, density, work ; energy in mechanical, thermal, and
electrical units ; hnrse-power, and temperature." Only
those who are familiar with graphic statics know what
can be done by diagrams, but even they will be astonished
at the wide range of conversions covered by Prof.
Smith's graphic equivalence plates. The diagrams will
principally aid the conversion of English and metric
measures, and vice versa, but they also represent the
relations between different systems of English, and of
French, measurement. We have always been attracted
by the method of expressing equivalents by means of
squared paper, and Prof. Smith's graphic tables have
greatly increased our admiration of it.

NO. 13 14, VOL. 5 I "I

LETTERS TO THE EDITOR.

[ The Editor does not hold himself responsible for opinions ex-
pressed by his correspondents. Niither (an he undertake
to return, or to correspond with the writers of, rejected
manuscripts intended for this or any other part of NATURE.
No notice is taken of anonymous communications.^

The Kinetic Theory of Gases.

I DO not feel as if ihose who heard me ask some questions
at the British As.<:ociation at Oxford, about the kinetic theory of
gases, exactly undfrstood my difficulties. They are those of an
oidoriker, and so ihey may be of general interest. As several
of ihem have been fairly salisfaciorily answered, it may be
worih while stating the present position of such an onlooker as
myself.

In the first place, consider the difficulty as to reversibility
and as to the number of possible ways in which a system could
be staned on a reverse path so as lo obtain 3. s^ivcn initial state.
This is, I think, completely answered in the way Mr. I. armor
gives in his letter on p. 152. As well as I can recollect, Mr.
Culverwell and I had been mutually sali.sfied by this kind of
explanation previous to the meeting at Oxford, and it was
not then referred to.

The questi m of reversibility lately started, as I understand
it, has reference to the introduction of the postulate of chance
in the deduction of the theorem about H. Mr. Burbury, in
his recent letter, has indicated a proof of this theorem, in
which he explicitly postulates chances, and so far iusiifies the
possibility of proof on these lines. I understand that Mr.
Culverwell is so far satisfied, and only asks for more, i.e. an
extension of this form of proof to other cases than the simple
one of colliding spheres.

Secondly, as regards the solar system, &c. , I am not yet
quite clear why a finite number of particles moving about for an
indefinitely long time does not satisfy the conditions of the
problem as usually slated, just as well as a larce number of
bodies for a short time. As to the necessity for collisions among
the parts of a system, I cannot see why the earth, moon,
Jupiter, and sun are not to all intents and purpose.? of the
generalised coordinates in collision at present and alway- ; and
I desired to know why any other kind of collision is required
for the applicaiion of the investigation. I think I now see,
through conversations with Mr. Culverwell, where the existing
investigations may fail to apply to solar systems. I may explain
my position as follows. It was always, I knew, postulated
that more than two particles should not be in collision at once,
and I therefore asked how this could be an essential part of the
investigation when applied to the case of air near the earth sub-
ject to gravitation. I did not see why the earth was not (so far
as the generalised coordinates investigation was concerned) a
particle in collision with every particle of the air during every
one of their collisions with one amther, and consequently
violating the postulate requiring only two particles to be in col-
lision simultaneously. I now understand that «hen dealing
with gravitation and such like forces, these are supjiosed to be
direcied to yf.ivt/ centres, and that in the case of a large particle
like the earth this is very nearly true, but that it could not be
even approximately true if we had three fairly equal particles
acting upon one another simultaneously. This may also explain
why the equal partition of energy does not hold in the solar
system where the bodies do not act upon one another in pairs,
but are all always subject to one another's action. This,
as I understand, is also the reason why the direct dis-
tance law is not an exception to the equal partition
of energy theorem. It also may explain how we can have water
and steam in equilibrium with one another, notwithstanding
the apparent uniijueness of the Boltzniann-Maxwell .solution.
From experience it would seem that when we can extend the in-
vestigation to the case of several bodies in simultaneous colli-
sion, we shall find that there are three solutions corresponding
to the solid, liquid, and gaseous states. At the same lime,
some of the very general investigaticus that seem to me, as a
physicist, as if they were intended lo apply to complex molecules
in collision with one another, and with a partition of energy
amongst the atoms, appear lo violaie the postulate of collisions
in pairs; for I find it hard to conceive of these molecular systems
of atoms as other than systems, the various parts of which are
held together by mutual actions, and which must c.nsequently

222

NATURE

[January 3, 1895

be considered to be ia simultaneous collision with one another.
Thi^maybe where the spectrum crux fails. Perhaps somebody
would be so very kind as to point out where exactly in these
generalised coordinate investigations the postulate of collisions in
pairs is used, and so save lazy people like me the trouble of
hunting it up.

This raises the third point as to how this difficulty abaut
the spectral lines is to be surmounted. I cannot follow either
Mr. Bryan's, or what I understood to be Mr. Larmor's view,
tha*. any help can be got by supposing spectral lines to be due
to electromagnetic vibrations. The example Mr. Bryan gives
of smooth solids of revolution is quite beside the point. In
this case there is no interchange of energy between rotation
round the axis of revolution and the other degrees of freedom.
This is quite contrary to what we know to be the case in respect
of ethereal and molecular energy. We know that radiations
cause bodies to become cooler, and therefore there is inter-
change of energy. This could not be otherwise, as is evident
from what we know of the mcch.inical forces — electric, magnetic,
ami electromagnetic — that interact between matter and ether.
It is rather hard for Mr. Bryan to say that the onus probandi
lies with f hysicisls to explain exactly hou' transference takes
place ; surely the fact that transference does take place is
sufficient to prove that a complete theory should take in both sets
of coordinates — ethereal as well as material — and I should have
thought that those formidable arrays of <ip^ dp, . . . dp,, &c.,
of coordinate; and momenta to the «th, with dots between to
signify their indefinite number, should include everything of
this kind that could possibly be required. Here, however, the
postulate of collisions in pairs entirely breaks down, and thus
shows a way out of this spectral difficulty. A second way was
suggested to me, by whom I forget, at Oxford, namely, that the
complicated systems of lines that we see in the spectrum — of
iron, (or instance — are so connected as to their amplitudes,
periods, and phases, as to represent only a single coordinate.
Anybody who has tried to expand a simple function in Fourier
series will easily understand how a very simple motion might
produce a fearfully complicated spectrum.

It seems, then, to me that the questions which need solving in
our study of the dynamical foundations of thermodynamics at
present are (i) how to explain spectra, and (2) how to deal with
several bodies in simultaneous collision ?

Geo. Fras. Fitzgerald.

Trinity College, Dublin, December 19, 1894.

The difficulties in the way of harmonising the spectro-
scopic phenomena of healed gases with the conclusions of the
Boltzmann-Maxwell theorem of distribution of kinetic energy,
appear to mc to have been fxaggerated.

This theorem asserts, as a purely dynamical proposition, that
a very large number of, say, billiard balls, perfect as to spheri-
city and elasticity, having been set in haphazard motion in a
space bounded or interrupted by perfectly elastic rigid surfaces,
if the volume of free space be sufficiently large as compared
with the total volume of the balls ' will, if left to itself, lend
to a certain stale of density and velocity distribution, and
having reached this stale, will remain in it permanently. The
billiard balls may be replaced by rigid bodies of any form, or
indeed by material systems capable of any changes of shape or
motion of the parts among themselves, and a corresponding
proposition still prevails — one general property holding good in
all cases, viz. that if u, v, w he the motions of translation of
each system as a whole, m its mass, T its total kinetic energy,
and » the total number of its degrees of freedom inclusive of the
3 of translation, then in the permanent state

2

mv-

2

J = T/«,

where - denotes mean value throughout the whole medium.

/'/iOT'//aciV there is a discontinuity in thij abstract proposi-
tion anfi ting it for the basis of physical investigation, e./^. the
imalleit possible want of perfect sphericity in the billard
ballt would appear to effect as complete a change in the
physical properties of the medium as if each ball became an

ellip-oid or tetrahedron, the mean being changed /fr

' of ca4C!i in which three or more
infinitely smaller (ban the number

solium from T/3 to T 6> and the difficulties introduced by the
spectroscope are founded upon this discontinui y. Doubtless
we cannot make n fractional, but it should be remembered that
the dynamical proposition only speaks of an ultimate state, and
ignores the rale of approach to that state. The continuity of
physical properties is maintained by attending to the continuity
of change in this rate. This rate I have estimated for a
particular case in the new edition of my short treatise on the
subject, showing that there may be a sensible permanence long
before the law of equal partition is established.

And, again, there is yet another point to be considered. The
passage from the thermal to the optical properties resembles
the passage from mere noise to music. Dynamically it is the
passage from irregular, haphazard motion, heat, to regular
periodic motion, light ; the former must be decomposed into its
equivalent harmonic motions, and the most important terms
retained, but there would be no necessary relation between the
number of these terms (sensible bright lines) and the number
of degrees of freedom of the molecule. H. \V. Watson.

I S I UrK<: ihat th«; avr
tph-^f- are al any instant m
of cai'S in whitn two only <•

NO. 13 14, vor. 51]

The Horn Expedition to Central Australia.

In your issue of September 27, 1S94, occurs a short notice of
the work of the Horn scientific expedition to Central Australia.
Reference is made therein to the discovery of a " new type of
marsupial " by Dr. Stirling. The animal in question was found
by Mr. South, a mounted trooper (or rather by his cat, who
brought it into the house), at Alice Springs. By him it was
presented on our arrival to Dr. Stirling, who had charge of
the anthropological work of the expedition, by whom it was
kindly handed on to me as officer in charge ol the zoological
department. The specimen was a male, and being desirous
of securing more, I stayed behind the party, and by aid of the
blacks procured two more specimens, both of them females.
The animal, which lives in holes amongst the rocks and stones,
is by no means common, as I h.id to ofler considerable quan-
tities of flour and tobacco to the blacks as a reward for its cap-
ture. .\fter a number of them h.ad been out hunting for several
days the total result was two more specimens, though as these
were females they formed a welcome addition to my zoological
collections. As the expression, "a new type of marsupial,'"
gives rise to too great expectations, it may be as well to state
that it is merely a new species of the genus Phascologale, dis-
tinguished, amongst other points, by itsremarl;ably fat tail and
by the nature of the striated pads on the soles of its feet. I
was able to make drawings of the animal alive, and on showin;;
these to the bkicks at Charlotte Waters, some 250 miles to the
south of Alice Springs, they were at once greeted with cries
of " Amperta, " the native name for the animal which they
look it to represent. Through the kindness of Mr. Byrne, the
head of Charlotte Waters Telegrapli Station, I have since
been provided with specimens of the ■'.\mperta," which on
examination turns out to be the rare form — only as yet, I be-
lieve, known from a single specimen — described by Kreflt
under the name of Chutoccrcus crislieanda, and subsequently
placed by Mr. Oldfield Thomas in the genus Phascologale.

These two species, and a new one of the genus Saiinthopsis,
which we secured amongst the sand-hills near Lake .Xmadeus, are
the most important finds amongst the marsupials which, owing
to the country traversed by us bein^; in the main of a desert
description, were by no means plentiful. In this region animals
can only be secured in numbers after rain, an experience which,
during three and a half monlhs' wandering, did not fall to ourlot.
However, as one result of Mr. Horns generous action in
equipping the expedition, I hope to be able to give a fairly good
general account of the fauna of the central desert region of
Australia. Towards the close of the notice referred to, it is said
that there is some doubt as to the manner of publication of our
results. Mr. Horn's intention is, 1 believe, to issue a senaralt-
volume, the various parts of which will deal with the branches
of science represented by the members of the scientific staff as
follows : —

Prof. R. Tate (chairman of the scientific staff), geology and
botany; Dr. IC. C. Stirling, anthropology; Mr. C. Winnecke
(leader of the expedition), surveying and meteorology ; Prof.
Baldwin Spencer, zoology ; Mr. J. A. Watt, geology and
mineralogy.

The volume will contain an accurate map, compiled by Mr.
Winnecke, of the central district drained by the Finke river.

January 3, 1895J

NA TURE

223

and will, by means of the reproduction of photographs, illustrate
some of the more imporlant physiographic features of Central
Australia. Baldwin Si'Encek.

Palseontology at the Royal School of Mines.

In reading the excellent review of the biography of Sir R.
Owen, which appeared in last week's Nature, I observe an
error which, though small, requires correction. It is stated
that when Owen surrendered his appointments at the College
of Surgeons he was "enabled to accept the lectureship on
Paleontology at the Royal School of Mines, in 1857." The
lecords of that Institution will s-how that Owen never held a
lectureship there, nor was he in any way connected with the
School.

The large theatre of the Museum of Practical Geology was fre-
<iuently employed for other purposes than those of the School, by
permission of the Director-General ; and it was in virtue of such
permission from Sir Roderick Murchison that Prof. Owen used
the theatre for the delivery of his lectures on Palaeontology to
the public, in 1S57 and subsequently. T. H. Huxlev.

Eastbourne, December 27, 1894.

Eocene Fossils at Murren.

I HAVK read with surprise the extracts from the letter
which you have received from Dr. Fellenberg on this sub-
ject. C3f course it has long been known that there are Eocene
strata at Murren. IJut below them lie calcareous rocks coloured
on the Swiss map as Malm, These are so described on p. 211
of the "Livret Guide," published by the International Geo-
logical Congress which met this autumn at Zurich. During
the subsequent excursion, under the able guidance of Prof.
Renevier, Prof. ^Golliez, and M. Lugeon, we were taken
to Murren and shown these rocks, and Prof. Golliez gave
us the reasons which had led some geologists to regard
them as Trias rather than Malm. It was in these cal-
careous bed.s that the layer containing nummulites was met
with. The train|was just starting, and we had to leave, but the
find excited so much interest that -M. Lugeon returned to Murren
the next day, with some of the party, and verified the exact
locality. John Lubbock.

High Elms, Farnborough.

The Use of the Globe in Crystallography.

In your issue of December 20, Mr. Buchanan revives a graphic
method of cr)stallographic calculation which seems to have been
used in the early part of the century {ridd " Zur physischen
Krystallonomie, &c.," (irassmann, 1829, p. 37), and claims that
by use of the globe and nutroip/iire "every problem in the
geometry of crystals can be solved with ease and accuracy."

Crystallographic angular measurements are said to be accurate
if subject to a probable error of less than two or three minutes,
and descriptions of inorganic substances are nowadays habitu-
ally published in which the probable errors are of this order.
Although no details of Mr. Buchanan's method are given, it
seems inconceivable that any graphic process of crystallographic
calculation, involving triangulation on a sphere, could be
accurately performed without the use of numberless tedious pre-
cautions and large and cumbrous apparatus.

It is usually more easy to grasp a good plane diagram of any
solid figure than to understand and follow up explanations on
the solid figure itself; the use of the latter is liable to lead to
inaccuracy of expression and confusion of thought. Thus,
when the sphere is used, the real meaning of the points which
Mr. Buchanan describes as cataloguing the edges occurring on
crystals, is not at once seen ; using the plane projection, it is
immediately apparent that these points are characteristic, not
merely of the edges, but in a much wider sense, of the zones :
they are merely the poles of the zone circles.

Further, the positions of the points representing the corners
are dependent on the iizts of the faces concerned, which, as we
teachers of crystallography are at infinite pains to impress on
our students, have no crystallographic signification ; these
points, then, are not chaiacleristic of the corners.

Similarly, the rather complicated piece of reasoning respect-
ing "reciprocal inversion forms" simply yields the well-known
result that in the cubic system, the octahedron truncates the
corners of the cube. \VtLLIA^t I. Pope.

Central Technical College, South Kensington.

NO. 1314, V(.L. 51]

"The Zoological Record."

It has long been a matter of regret that the Zoological
Record is not sold in separate parts ; a specialist requiring any
one part being required to pay for all the others, though they
may be of no more use to him than so much waste-paper.

In order to remedy, to some extent, this unfortunate stale of
things, I am proposing (if sufficient support is forthcoming) to
purchase the Zoological Accord as published, and to issue the
separated parts to subscribers. With this view, I would ask all
those desiring any part (of the volume just issued, or of past
volumes) of the Zoological Record, to communicate with me
a.i soon as possible, stating which part they would be willing to
subscribe (or.

Although it is, of course, not intended to make a profit out of
this scheme, it will nevertheless be necessary to charge slightly
more for the separated parts than their proportionate value, as
some parts are almost certain to remain unsold.

I am confident that this scheme will not in any way injure the
Zoological Society ; in fact, although they maintain the con-
trary, I am sure it would be to their advantage to issue the parts
separately, if necessary at a slightly higher rate. At present
subscribers are, I believe, mostly libraries and societies, re-
quiring the whole volume. These would, of course, continue to
subscribe for all parts, even if they were obtainable separately ;
while, on the other hand, all specialists who do not subscribe
under the present arrangements would be practically certain to
purchase those parts dealing with their own subjects, if obtain-
able at a moderate cost. If the proposed scheme meets with
support, it will go a long way towards proving the justice of the
foregoing contention, and in that case it will probably be
possible to induce the Zoological Society to grant the concession
for which many zoologists have for long been agitating.

Royal College of Science, London. S. PACE.

Gravitation.

In answer to Dr. Lodge's letter, I may state that Newton in
his " Opticks " (Query 21) asks if an increase of density of the
ether outwards from bodies will not account for gravitation,
every body endeavouring to go from the denser parts of the
medium towards the rarer ; and if such increase of density may
not, even at great distances, be effective, provided the elastic
force of the medium be sufficiently great.

I do not think a tensile ether is contemplated in this theory
of gravitation. Prof. Worthington's effect manifests itself only
in a tensile liquid, and this constitutes its suggesliveness in
connection with the hypothesis of a tensile ether. I have no
such definite ideas to advance as are put forward in the
" Opticks." J. J01.Y.

Trinity College, Dublin.

The Feigning of Death.

The curious condition of apparent death, assumed by the
English grass snake, which Mr, G. E. Hadow describes
(NATUfiE, December 6, p. 127), is one that I have fre-
quently observed, but have always been puzzled to account
lor I hardly think that it has anything to do with simulation,
or that it is voluntary, since I have seen snakes so affected
when quite undisturbed in their cases. I have also observed
precisely the same state in the common Italian snake. In my
experience the condition only occurs in fairly hot weather, and
when the snake h.as not fed for some time. This seems to
point to a species of fainting fit, and I imagine that it is imme-
diately induced by a disturbance of the cerebral circulation.

R. Harry Vincent.

Leytonstone, December 30, 1S94.

Peculiarities of Psychical Research.

In reply to Prof. Pearson : (l) His remark about "scientific
acumen " was not made ii profos of M. Richet's experiments,
but of those of the S.P.R. ; and hardly any stress is laid on M.
Richet's results, either by Mr. Gurney or Mr. Podmore. Mr.
Gurney, on the contrary, expressly says : "Clearly no definite
conclusion could be based on such figures." But if Prof.
Pearson has made experiments which are equally striking in the
opposite sense, I wish he would publish them, or communicate
them to the S.P.R. (2) There was nothing in my letter to
indicate that I under-estimated the importance of "abnormal
distributions"; but I asked Prof. Pearson to say whether he

224

NATURE

[January 3, 1895

had any reason to suppose such dislributions might have
occurred in the case in dispute. This he has failed to do— he
has evaded the point. (3) Prof. Pearson descends to vague
generalitie-i except in regard to Dr. Oliver Lodge, who may be
left to dclend himself.

With the last paragraph of the letter, however, I heartily
concur. There is nothing the S.P.R. would welcome more
than intelligent and independent criticism. Only the critic would
have to study the evidence first, and the Professor apparemly
has the '• scientific acumen " to see that by doing so he would
cut his own throat ; for he would, ipso facto, become a psychical
researcher ! Edward T. Dixon.

Cambridge, December 29, 1S94.

ON THE AGE OF THE EARTH.

IT has been thought advisable to publish the following
documents. On October 12 I put my views before
Prof. Fitzgerald and Dr. Larmor. The first paper is a
copy of my letter to Dr. Larmor. It has now been edited
a little, as originally it was rather hurriedly written.
Some long mathematical notes, added on .November i,
to prove the legitimacy of my appro.ximate method
of calculation, are now omitted, as Mr. Heaviside has
given exact solutions, and has found that there is
practically no difference between mine and the exact
numerical answers. That Mr. Heaviside should have
been able, in his letters to me during eleven days, to work
out so many problems, all seemingly beyond the highest
mathematical analysis, is surely a triumph for his new
methods of working. Only for Prof. Fitzgerald's encour-
agement and sympathy, it is very probable that this
document would never have been published.

I have sometimes been asked by friends interested
in geology to criticise Lord Kelvin's calculation of the
probable age of the earth. 1 have usually said that it is
hopeless to expect that Lord Kelvin should have made
an error in calculation, liesides, in every class in mathe-
matical physics in the whole world since 1862 the problem
has been put before students, and, as the subject is of
enormous interest, if there had been any error it cer-
tainly would have been discovered before now.

I dislike very much to consider any quantitative
problem set by a geologist. In nearly every case the
conditions given are much too vague for the matter to be
in any sense satisfactory, and a geologist does not seem
to mind a few millions of years in matters relating to
time. Therefore I never till about three weeks ago
seriously considered the problem of the cooling of the
earth except as a mere mathematical problem, as to
which definite conditions were given. But the best
authorities in geology and paUtontology are satisfied
withevldences in their scicncesof a much greater age than
the one hundred million years stated by Lord Kelviri ;
and if they are right, there must be something wrong in
Lord Kelvin's conditions. On the other hand, his cal-
culation is just now being used to discredit the direct
evidence ol geologists and biologists, and it is on this
account that I have considered it my duty to question
Lord Kelvin's conditions.

The original object of Lord Kelvin's investigation is
usually forgotten. He sought to prove, and proved, that
the earth is losing energy at a calculable rate. He said
that the loss might be the loss of potential or chemical
energy instead of sensible heat, or as well as heat,
although he thought that a large proportion of
potential or chemical eneigy was improbable ; and it is
only on the assumption that the earth is a cooling body
losing energy originally only of the sensible-heat form,
that bis calculation of the age of the earth is based.
Not only so, but also his earth is a homogeneous mass of
rock such as we have on the surface, with the same con-
ductivity and other heat properties. He starts with the

NO. 1314, VOL. 5']

knowledge that there is an average increase of tempera-
ture downwards in the earth of one Fahrenheit degree
for every 50 feet. Assuming that the earth, a solid, was
once at the uniform temperature of 7000 F., that
its surface was suddenly brought to and kept at the
temperature o, and taking /vt" ik being conductivity
and c capacity for heat of unit volume, in year foot units)
as 400, he finds that lo"" years have sufficed to cause the
temperature-gradient at the surface to be what it is now.
He stated that the conditions were sufliciently repre-
sented by an infinite uniform mass of matter at 7000'
F. with an infinite plane face kept at o.

At first I preferred to consider a globe of 4.000 miles
radius of constant surlace-emissivity to be cooling as if
in an enclosure, kept at constant temperature. 1 nude
the emissivity infinite, and obtained Lord Kelvin's
answer for temperature-gradient near the surface. When
the emissivity is taken of a finite value, the time taken
to produce the present temperature-gradient is less than
Lord Kelvin's answer.

It is interesting to notice that if we take our enclosure
to be at a zero of temperature which we can choose as
we please, we have a method of using Fourier's expres-
sion in certain cases in which the emissivity is not con-
stant. I3y no method of working does it seem probable
that we shall greatly alter Lord Kelvin's answer.

Modification of Lord Kelvin's Conditions.

But, when we depart from homogeneity, when we
assume that the interior of the earth may be of better
conducting material than the surface rock in which the
temperature-gradient is alone measured, we find a very
different state of things from that considered by Lord
Kelvin. The cooling from a constant temperature of an
infinite mass bounded by a cold plane face, a slice of
which near the surface is of inaterial different from the
rest of the infinite block, is a problem difficult to attack
mathematically. But if the slice is thin, or if much
time has elapsed, the following artifice leads to a
solution.

Imagine an infinite homogeneous block, originally at
temperature V,, whose surface is kept at o. If ii is
sufficiently small and / great, we may neglect the ex-
ponential term, and (:' being temperature and /time, and
.r ' "

• the distance from the cold face)

Vi -i- sJtkJ; 7'i at .ii = V,j-,

dx

^/wKj/.

Rate of liow of heat across unit area at .1 , = i\V, -7-
s'ttk,/. I take i as conductivity, and k as conductivity
divided by capacity for heat of unit volume.

Now take another such homogeneous infinite block of
different material, and use the letters with affix 2 instead
of I. Let the time be the same in both. Let the sur-
face slice from 1, to o in the first, and from .r. to o in the
second be considered. We can, by taking proper values
of V| and V. and .r, and .v-., make the rates of How of
heat equal and the temperatures equal at .r, and .v., :

/•,V,/ Vi = ^••jVj/Vj and V,..,/v'ki = V,.s\Vj

Hence -(•, -H r, = i:, -i- x... Thus if /;/-.. = X„ we take

nX; = X,. r , I

Now we can take the slice x., to o from the second
block and let it take the place of the slice x, to o on the
first block. The artificial block so produced will go on
cooling, its outside face being kept at o,. But we shall
have at the point of junction a sudden nniltiplication of
dv dr. In fact, dr dx will be what it used to be towards
the interior, but will be // limes as great towards the
surface. It is of no consequence what the value of «..
is, if times are great and slices thin, the only impurlant
thing is that /•, shall be n times k,. The application ol
the result is obvious : —

January 3, 1895J

NATURE

225

Let the interior of the earth be a uniform sphere,
uniformly heated to 7000' F. Take its icas tii times what
Lord Kelvin took it, then an increase of temperature
downwards from the surface of I F. degree for every
50 n feet would be produced in loV/- in years. Take its
k as « times what Lord Kelvin takes. Now if we imagine
a skin removed and replaced by one of i «th of the
thickness and i n\.\\ of the conductivity, that is, take it of
Lord Kelvin's conductivity of rock, the surface slope will
be I in 50, what it is now, and Lord Kelvin's time will
be increased in the proportion ri-'in.

Considering the great differences in conductivity of
such bodies as we know, it is quite conceivable in our
knowledge and ignorance of the interior of the earth that
«- III may be considerable even now, and probably was
very considerable in past times. Roughly we may say
that Lord Kelvin's age of the earth, 10'* years, ought to
be multiplied by two to six times the ratio of the internal
conductivity to the conductivity of the skin.

I am not in a position to criticise the arguments from
tide phenomena which Lord Kelvin or Mr. Darwin would
now put forward on the subject of much internal fluidity
of the earth. The argument from precession has been
given up. Of course much internal fluidity would prac-
tically mean infinite conductivity for our purpose. But
there is no doubt of a certain amount of fluidity inside
even now, and taking it that the inside of the earth is a
honeycomb mass of great rigidity, partly solid and partly
fluid, we have reason to believe in very much greater
quasi-conductivity inside than of true conductivity in the
surface rocks, and if there is even only ten times the
conductivity inside, it would practically mean that Lord
Kelvin's age of the earth must be multiplied by 56.'

If we imagine the earth perfectly conducting inside
with a thin covering, say 60 miles thick, of rock, such as
we know it on the surface, we must leave Lord Kelvin's
infinite mass and study the sphere. Indeed, if we take
it that we have now an infinite mass at 7000 F. of infinite
conductivity, cooling through rock of from 60 to 70 miles
thick wah a constant gradient of I for every 50 feet, we
can imagine that this state of things has existed for an
infinite time, and any original distribution of tempera-
ture in the rock would settle down to such a state.

Taking, then, an internal sphere of infinite conduc-
tivity - (and working in C.G.S. Centigrade units), its
specific heat 02, and the conductivity of the rock o'O02,
I find that if at the beginning of time there was an
increase of 1 Centigrade in 45 feet, and now there is an
increase of i Centigrade degree in 90 feet, the lapse of
time is 28,930 million years, or 290 times Lord Kelvin's
age, and the core has cooled from Sooo 10 4000 degrees.
Or, again, in the last 10'* years the gradient has only
diminished by i 400th of its present value, and the core
has only changed from 4010 to 4000 degrees.

I do not know that this speculation is worth much,
except to illustrate in another way the augmented answer
when we have higher conductivity inside. It would evi-
dently lengthen the time if I assumed that the tempera-
ture-gradient was not uniform in the shell, but the exact
mathematical calculation is so troublesome that I have
not attempted it ' John Pkrrv.

31 Brunswick Square, London, W.C, October 14.

' Observe th.it, even if we assume th.it there is the same conductivity in-
side and outside, inasmuch as the density is Rrcaler, c is greater, say 3
tiijics as great, and even without the assistance ot increased conductivity
mside. we have 3 times Lord Kelvin's age. I .admit that all such spectilation
.-vs to the value uf tis too vague to be of much importance.

- If 0^, and 0 were the internal temperatures at the times i^ and /, if b is
thethicl^ncss of the crust and R ihj radiusof the internal sphere, if s is its
speciBc heat and p its density and k its conductivity,

t-t^

_K6sp
' 3*

log "^K

3 If '006 be taken as the conductivity of rock, the times are only a third
of what 1 have given.

In connection with this matter I notice that in Lord Kelvin's very short
p.il>er, entitled ''Ihe 'Doctrine of Uniformity" in Geology briefly

NO. I 3 14, VOL. 5 l]

October 22, 1894.

The reasoning in my paper was applied either to
infinite blocks of cooling material or to a sphere with an
internal core which has infinite conductivity. At the
time of writing I did not see my way to the consideration
of a sphere with a core of finite conductivity and a shell
of rock as a covering, but the case is really easy to work
when the shell is only a few miles in thickness, as will be
seen below.

Prorlem.— A sphere of radius R = 638 x lo'^centim.
of conductivity k = o'47 (or 79 times that of surface-rock)
and kic = 0-16464 (or 14 times that of surface-rock), has
upon it a shell of rock of thickness 4 x lo'centim. (about
2.', miles). The whole mass was once at a temperature
V' = 4000' C, and suddenly the outside of the shell was
put to o" C. and kept at that. Find the time of cooling
until the temperature-gradient in the shell has become
I Centigrade degree in 2743 centim. (or 1° F. in 50
feet).

Now, if we are allowed to assume that the shell very
rapidly acquired and retained a uniform temperature-
gradient throughout its thickness, and it is easy to show
that this assumption is allowable (or if not, then the
discrepance is in favour of a greater age for the earth),
the problem is exactly the same as this : — The above-
mentioned sphere has no shell of rock round it, but
emits heat to an enclosure of o' C, the constant emissi-
vity of its surface' being E = 1-475 X lo"" ; find the
time in which the surface-temperature f' becomes 146' C.

This problem is solved by Fourier, who gives for the
temperature at the distance r from the centre

_ 2VER ,sin erIK r^''""^'

k er/[<. e cosec e ~ cos e

where in the successive terms the values of e to be taken
are the successive roots of the equation

(f/tan e = I - ER/>C-.
In the present case ER /■ — 20, and r,, e.^ t',, &c., are
nearly t, 27r, 37r, ^c. I have, however, taken the actual
values oie^ and e.,- two exponential terms, only, being of
importance, and I findthat, if / = 96 X lo** years,
v' - 1427 + 5*65 = 148-4;

ist term 2nd icrm

so that the age of cooling to the present temperature-
gradient is more than 96 X 10^ years.

Refuted," read before the Royal Society of Edinburgh in 1065, he finds : —
'■ But the heat which we know, by observation, 10 be now conducted out of
the Earth yearly is so great that if this action had been going on with any
approach to uniformity for 30,000 million years, the anmunc of heat lost out
ot the Earth would have been about as much as would heat, by 100" Cent.,
a quantity o( ordinary surface-r(^ck 100 limes the Earth's bulk." (The italics
are mine.) In his address on "Geological Dynamics," Part II., published in
1869 (p. i'j6, vol. ii. " Popular Lectures and Addre.'ises"). he calculates the
total amount of energy which wr/j* once have been possessed by the Eartli
mass, partly gravitational and partly chemical, as " being about 700 limes as
much heat as would raise the temperature of an equal mass of surface-rock
from 0° to ico' Cent." (The italics are mine.) I do not think that these two
siatenienis hiive ever before been put in juxtaposition. Comparing them,
we may say that, according to Lord Kelvin's own figures, if the present
action had been going on with any approach to uniformity for lo''" years the
amount of heat lost by the Earth w.aild have Leen the i/ySooth part of
the whole energy whicli the whole Earth may once have possessed, or
i/223oth part ol what Lord Kelvin gives as an estiniaie, an over-estimate he
calls it (l>ut he says that it is not possible to make one much less vague), of
the whole amount of heat at present in the Earth. I mention this because
some mathematical physicists beheve that Lord Kelvin baited his age of the
Earth upon a calculation of this total lo^s. He only used it in oppo-^ition to
the extreme docirme o' uniformiiy for the past 20,000 million years (a doc-
trine which is not now believed in by any geologist), but it lends no sup-
port to his calculated age ol the Earth;.

All through this paper I give ro^ years as Lord Kelvin's age of the Earth.
His own words {Trans. /\.S. Edin.y 1862(7) are: — "We must, therefore,
allow Very wide limits in such an estimate as I have attempted to make;
but [ think we may with much probability say th.at the consoli^fation cannot
have taken place less than 20,000,000 years ago, or we should have more
underground heat than we actually have [he means a more rapid increase of
temperature downwards], nor more than 400.000.000 years ago, or we should
not have so much as the least observed underground increment t f tempera-
ture." Taking the average difTusivity for heat of the Edinburgh experi-
ments, he finds (r) that the present temperature-gradient of 1 Fahr. degree
for every 50 feet gives a life of lo^' years.

■' Because if ;»' is the surface-temperature of the sphere and b the thick-
ness of the shell of rock, f'/iS was the surface-gradient in the shell and t-'/^
cnultiplied by conductivity of rock is eiiual to Ef'.

226

NA TURE

[January 3, 1895

If we take k as 195 times that of the surface-rock, and
k'c as 35 times that of the surface-rock, and if the shell
has a depth of 3272 x lo' centimetres (about 20 miles),
the time of cooling until the temperature-gradient is
I Cent, degree in 2743 centim. is wo/-^ than 127 X 10*
years." '

I kept no copy of the letter which 1 sent to Prof. Tail
with the foregoing document. In it I e.\plained my diffi-
culty in getting Lord Kelvin to re-consider the internal
heat question, and I asked for his advice.

Extract from Letter of Prof . Tail, November 22, 1894.
. . . my entire failure to catch the object of your paper. For
I seem to gather that you don't object to Lord Kelvin's mathe-
matics. Why, then, drag in mathematics at all, since it is
absolulely obviou.'; that the better conductor the interior in com-
parison with the skin, the longer ago must it have been when
the whole was at 7000° F. : the state of the skin being as at
present ?

I don't suppose Lord Kelvin would care to be troubled with
a demonstration <il that.

As to the validity, crmore properly \.he fluusibilily of his or
your assumptions, I don't suppose anyone will ever be in a
position to judge. He took the simple and apparently possible
case of uniform conductivity all through — having no data what-
ever. What if he had assumed, as he was quite entitled to do, that
the conductivity diminishes very fast with rise of temperature?

But I need not say any more, as I seem to have entirely
missed your point.

Letter to Prof. Tail, Novemlie:- 26, 1S94.

Dear Prof. Tait,— I should have been on the whole better
satisfied if you had opposed my conclusions. Vou say I am
right, and you ask my object. Surely Lord Kelvin's case is
lost, as soon as one shows that there are possible conditions as
to the internal slate of the earth which will give many times the
age which is your and his limit. . . . What troubles me is that
I cannot see one bit that you have reason on your side, and yet
I have been 50 accustomed to look up to you and Lord Kelvin,
that I think I must be more or less of an idiot to doubt when
you and he were so " cocksure." The argument from the sun's
heat seems to me quite weak. Even a geologist without mathe-
matics can see that the time given by Lord Kelvin will be in-
creased if we assume that in past limes the sun radiated energy
at a smaller rale than at present, much of its mass being possibly
cold atd in the meteor form, and the rate m-iy have greatly
varied from lime lo lime. This is not only possible but
probable, and it is for you and Lord Kelvin to prove a negative.

Then the Tidal Relarda' ion argument I Even if your rate of
retardation is correct, the real basis of your calculation is your
asiumption that a solid earlh cannot alter its shape (diminishing
its equatorial radius by a few miles) even in 1000 million years, 1
under the action of forces constantly tending to alter its shape,
and yet wc see the gradual closing up of passages in a mine, and

^ion for any case is ttii> ; — A sphere of radius R of
M:ity per unit volume iticin surrountjed by a shell of
V, and capacity for heat per unit volume c ; take
■: temperature at the surface, cqu.-ii to /■,'t74y':

we know that wrinkling and faults and other changes of shape
are always going on in the solid earth under the action of long-
continued forces. I know that solid rock is not like cobbler's
wax, but 10' years is a very long lime, and the forces are great !

I had thought these two arguments to be mere supporters of
ihe internal heat one which I took to be Ihe only important
one, like a diamond whose pure sparkle was brought into relief
by two rubies.

If I were alone in my opinion, I should still have the courage,
I think, to write as I do ; but as I have already told you, I did
not venture to write and speak to Lord Kelvin, or write to you
until I found that so many of my friends .igreed with me —
Fitzgerald, O. Reynolds, I.armor, Henrici, Lodge, Ileaviside,
and many others. Fitzgerald is the only man to whom I have
mentioned my notion about the sun's heat, but he quite agrees
with me. I have not put before him my notion about the Tidal
Retardation argument. . . .

November 27.
Dear Prof. Perry. — 1 should like to have your answers to
t:^'0 questions : —

(t) What grounds have you for supposing ihe inner materials
of the earlh to be belter conductors than the skin ?

(2) Do you fancy that any of \\\e aJvaiice^i geologists would
thank you for 10'" years instead of 10' ? Their least demand is
for 10'- : — (or fart of the mere secondary period I

Yours truly,

P. G. Tait.

' Th' ,-tn.:r.! .
cori'.
thiot
E .

The:,

e
Ian e

R/bii.

.2VR j5in£

All e

* - 4 sin 2e

a'743'

enables / to be calculated. It would no doubt be possible, but il would
hardly }>e worth while, to find the %'alucs of m and 6 which would give a maxi-
mum vaUic for /. In one of the above ca»es I took r nearly it. and in the
other 7/3.

lam quite unable to attack the problem of the cooling of a sphere from an
arbitrary initial condition, in which the dilTusivity for heat is an arbitrary
function of r.

T • 'i'lnof ^L wfi, ..vc a greater age to the

Ear' .•, a;;ain, it ■' o worth whito to spend

mu' Mv 7"tri -n to fix a hijjhcr limit

to thr a;;- .,t ir.r 1 t!,at such a higher limit

must be greater f ^Ired inillion years.

Sorr- of my *: f : not publishing the

abf'-' .ind am still his

aff' . '.tolcn from him,

as I I , liecn uniformly

kind 1'- tr:', . r, 1 tK'tr l,.nr !'• i t.ni-.«lir,, l„ ,i,,j,i |,jve fouud this
difficult. One thinK has not yet happened ; 1 have Dot yet receis'ed the
Ihirty pieces '>f silver.

Noz'ei/iber 29, 1S94.

Dear Prof. Tait,— It is for Lord Kelvin lo prove
that there is not greater conductivity inside. Nevertheless I
will slate my grounds : —

I (o). In page 6 of the paper sent you I say " I am not in
a position to criticise the argument from tide phenomena
which Lord Kelvin or Mr. Darwin would now put forward on
the subject of much inleinal fluidity of the earlh. The argu-
ment from precession has been given up. Of course, much
internal fluidity would practically mean infinite conductivity for
our purpose. But there is no doubt of a cerlain amount of
fluidity inside, even now, and taking il that the inside of the
earth is a honeycomb mass of great rigidity, partly solid and
partly fluid, we have reason lo believe in very much greater
quasi conductivity inside than of true conductivity in the surface
rocks."

1 ($). Even if we assume perfect solidity, and even neglect-
ing our knowledge of much iron — surely there can be no doubt
of the conductivity of rock iiiiieasing with the temperature.
From Ihe analogies with electric conduction, one would say,
without any experimenting, that as a metal diminishes in con-
ductivity with increase of temperature, so a salt, a mixture of
salts, a rock, may be expected to increase in conductivity with
increase of temperature. I presume that Evereit's book is
recognised now as giving the most exact information on these
subjects. He nowhere suggests that rock diminishes in con-
ductivity with temperature. Every case he gives shows an
increase. I have made out the following table from the only
quotations which Everett gives from Dr. Robert Wel)er ; only
five cases, but probably representative.

Percentage increase for a rise of 100° Centigrade.

.Mic.iceous gneiss
Mica schist
Eurile ,..

Gneiss

Micaceous schist

conductivity.

In speciiic heat.

48-0

236

13'' 4

24-4

1856

35-7

21-4

61 5

94'5

3S-4

Average ...

Average, leaving out
Eurite

431

75

NO. 1.3 14, VOL. 51]

Even if the conductivity and speciiic heal did not alter,
inasmuch as Ihe internal density is grcaler, the volumetric
capacity is greater ; and if it is three limes as great, we have
three limes Lord Kelvin's age. In fact, the rule given at page
4 of my paper is Ihc same as this : — If the conductivity inside is

January 3, 1895]

NA TURE

227

« times the conductivity outside ; if the specific heat inside is
s times the specific heat outside ; if the density inside is d times
the density outside ; then Kelvin's age of the earth is increased
Ki (/times. . . It is not likely that Dr. Weber's rate of increase
would be constant to such a temperature as 4000 C. ; but the
electric analogue allows us to imagine a greater and greater rate
of increase at higher temperatures ; therefore it is in Lord
Kelvin's interest to take Weber's rate, Now at 4000" C. the
conductivity would be [leaving out eurite, which seems abnor-
mal and too much in my favour], thirty times as great as it
is at the surface ; the specific heat would be \\\ times as great,
and taking the density as three times, we have, even for a pei-
ft'ctly solid earth an age 1300 times the age given by Lord
Kelvin.

2. In answer to your second question. Lord Kelvin com-
pletely destroyed the uniformitarian geologists, and not one
now exists. It was an excellent thing to do. They are as
extinct as the dodo or the great auk.

I have met many advanced geologists, and not one of them
demands more than 1,000,000,000 years. Probably Sir Archi-
bald Geikie is the most representative of the geologists who
have studied this question, and he never (in recent years) seems
to have desired even as much as 1,000,000,000 years. (See his
address as President of the liritish Association.) The biologists
have no independent scale of time ; they go by geological time.
According to Huxley, less than 1,000,000,000 years is enough as
the age of life on the earth.

But surely the real question now is not so much what the
geologists care about, as — Had Lord Kelvin a right to fix 10*
years, or even 4 x 10' years, as the greatest possible age of the
earth ? Yours truly,

John Perry.

Dcicmber 6, 1S94.

Dear Prof. Tait, — Prof. Fitzgerald has pointed out to
me that the five rocks given by Everett are not to be found in
his 1891 edition. I quoted from his 1886 edition. I therefore
wrote to Everett, asking why he had left them out — was there
a mistake ? He writes to say : " I copied Weber's data from a
copy of his paper which wa.s, and may be still, in my posses-
sion, having been sent me through the post, probably by the
author, or possibly by Dr. Stapff, the geologist of the St.
Gothard Tunnel, with whom I had much correspondence in
underground temperature. You seem to assume, in writing to
Tail, that I picked out samples of Weber's results ; but my
recollection is that I gave everything without reservation.

" I did not reproduce his results in the 1891 edition, and I
cannot remember all my reasons lor dropping them. On com-
paring them with other people's, which I give, they appear to
be much too small. There is such a mass of conduction results
in my book, that I was on the look-out for something that might
be omitted.

"I have just referred to the foreign translations of my book. The
German edition, published in 1888, gives only a page of conduc-
tivities of solids, and includes among them one of R. Weber's,
namely Glimmerschiefer 000733 + 'ooooio t. The Russian
edition, brought out by editors who took tremendous pains in
verifying and correcting references, gives my list of Weber's
results exactly as it stands in my book, the sign of the
temperature coefficient being positive in every case. I do not
know of any direct evidence as to the variation of rock con-
ductivity with temperature except R. Weber's, but there is
something approaching to direct evidence in the comparison of
George Forbes' results with Herschel and Dunn's (see my 1891
edition, pp. 126, 129). Forbes found at - 10° C. the con-
ductivity of white marble to be '00115, black marble '00177.
Dunn and Herschel found at the temperature of hot water,
marbles, &c., 0047 to 0056 (see Forbes' remark, quoted at p.
129).

" You have built a very lofty edifice on the basis of Weber's
results, and extrapolation is proverbially a risky process, but I
consider you have established a strong presumption in favour
of the increase of rock conductivity with temperature."

I did not know, when writing to you on November 26, that
the Rev. M. H. Close, M.A., had (K. Dublin Soc, Feb. 1878)
put forward in great detail the reasons which I gave you
shortly, against the tidal retardation argument. I thought they
were my own. I notice that this gentleman assumes that in-
creased conductivity inside would help Lord Kelvin, and indeed
1 cannot help thinking that, without mathematics, almost any-

NO. 1314, VOL. 51]

body would be of the same opinion — in spite of whit you say in
your first letter. I know that Lord Kelvin himself did not seem
to think me right when — after I had sent him the documents—
I talked to him at Cambridge.

I remain, yours truly,

I"HN Perrv.

Copy of a Letter from Lord Kelvin.
The University, Glasgo-M, December 13, 1894.

Dear Perry,— Many thanks for sending me the printed
copy of your letter to Larmor and the other pipers, which I
found waiting my arrival here on Saturday evening. I have
been much interested in them and in the whole question that
you raise, as to the effect of greater conductivity and greater
thermal capacity in the interior. Your «- ^ m theorem is
clearly right, and not limited to the case of the upper stratum
being infinitely thin. Twenty or thirty kilometres tnay be as
good as infinitely thin for our purposes. But your solution on the
supposition of an upper stratum of constant thickness, having
smaller conductivity and smaller thermal capacity than the
strata below it, is very far from being applicable to the true case
in which the qualities depend on the temperature. This is
a subject for mathematical investigation which is exceedingly
interesting in itself, quite irrespectively of its application to the
natural problem of underground heat.

For the natural problem, we must try and find how far Robert
Weber's results can be accepted as trustworthy, and I have
written to Everett to ask him if he can send me the separate
copy of Weber's paper, which it seems was sent to him some
time before 18S6; but in any case it will be worth while to
make farther experiments on the subject, and I see quite a
simple way, which I think I must try, to find what deviation
from uniformity of conductivity there is in slate, or granite, or
marble between ordinary temperatures and a red heat.

For all we know at present, however, I feel that we cannot
assume as in any way probable the enormous differences of con-
ductivity and thermal capacity at different depths which you
take for your calculations. If you look at Section 11 of
" Secular Cooling " (" Math, and Phys. Papers," vol. iii. p.
300), you will see that I refer to the question of thermal con-
ductivities and specific heats at high temperatures. I thought
my range from 20 millions to 400 millions was probably wide
enough, but it is quite possible that I should have put the
superior limit a good deal higher, perhaps 4000 instead of 400.

The subject is intensely interesting ; in fact, I would rather
know the da'e of the Consistentior Status than of the Norman
Conquest ; but it can bring no comfort in respect to demand for
time in Palaeontological Geology. Ilelmholtz, Newcomb, and
another, are inexorable in refusing sunlight for more than a score
or a very few scores of million years of past time (see " Popular
Lectures and Addresses," vol. i. p. 397).

So far as underground heat alone is concerned you are quite
right that my estimate was 100 millions, and please remark
(" P. L. and A.," vol. ii. p. 87) that that is all Geikie wants ; but
I should be exceedingly frightened to meet him now with only
20 million in my mouth.

And, lastly, don't despise secular diminution of the earth's
moment of momentum. The thing is too obvious to every one
who understands dynamics.

Yours always truly,

Kelvin.

JUPITER.

JUPITER being now near opposition, and having an
apparent diameter of 47 ■/, is displayed as a very
brilliant object in the heavens, and his northerly
declination of 23 degrees enables him to remain above
the horizon for a period of i6j hours.

During the few ensuing months, the observation of his
belts and spots will enlist a large amount of attention,
for there is probably no other planetary object which
exhibits a more diversified and variable aspect. One
feature of the present observations will be important as
enabling comparisons to be made as to the rates of
motion of the various white and dark spots in this and
preceding oppositions. No doubt many of the surface

22S

NATURE

[January 3, 1895

markings now existing are identical with those observed
some years ago. From 1S7S to 1SS2 the prominent
appariti<^n of the red spot incited observers to fully
investigate the phenomena of the different formations,
and they were found to be very discordant in their rates
of velocity. The red spot and equatorial white spots
were evidently subject to a marked retardation, causing
their rotation periods to increase with the time.

As to the red spot, the slackening rate of motion it
exhibited in the earlier years of its presentation, appears
not to have been maintained since 1SS6, for Mr. Marth's
adopted period of gh. Sjm. 40 633. (equivalent to a daily
rate of 870^27) has correctly represented its mean
motion during the last eight years. There have been, it
is true, some marked deviations from the mean rate, for
in the years from 1SS6 to 1S90 the motion became
accelerated and corresponded to a rotation period of
about 9h. 5Sm. 40 2s., but in the three following years it
slackened again, and since 1891 the period has been
about 9h. 55m. 41 'Ss.

At the present epoch the spot is extremely feeble in its
visible outlines, but on a really good night its elliptical
form can be distinctly traced, and it does not appear to
have materially changed either in its shape or dimensions
since 1S79. Its following end is decidedly the plainest,
and its southern borders have lately been conjoined with
a grey belt in about latitude 30' south. The com-
mingling of the spot and belt has been noticed here on
previous occasions, and it is certain that on its southern
side the spot exerts very little of the repellent influence so
often ascribed to it. On the contrary, the belts on the
equatorial side of the spot always run clear, and abruptly
bend north to allow of a clear while interval between the
spot and bell. The S. border of the spot and S. belt were
apparently in touch early in the past autumn, for Mr. Bar-
nard, observing the red spot with the 36-inch refractor of
the Lick Observatory, says: '"The belt south of it seems
to be in contact, if it iX^<t^ xv t actually overlap it slightly."
The same thing wa= noticed as long ago as October 31,
1893, by the aid of the 16-inch refractor of the Goodsell
Observatory, Minnesota, when the observers wrote " the
great red spot was seen by us, and the colour was exactly
the same as that of the belt just to the south of it, and
the two objects merged into one another without the
slightest change in intensity of colour."

The spot now arrives at mid-transit two or three
minutes after Mr. Marth's zero meridian, as the following
observ.iii(.n-, ni.iile here will indicate: —

Miii.tr.tn-iit I'ollows Marth's Long, of
- , of spcit. zero ineridUin. spot,

h. m. m. ,

Novctnl)«r 25 10. 50 4-2 2-9

December 12 9 46 f2 07

19 «o 33 35 21

It is well known that the perception of a delicate
planetary marking depends in a very great measure on
the quality of the definition. On an indifferent night the
red spot is practically invisible, but with steady air and a
sharp image the familiar pinkish ellipse, now represent-
ing that object, shows up distinctly in the remarkable
concavity of the great southern equatorial belt. The
latter configuration always offers an excellent guide to
the position of the spot, but its appearance is not
symmetrical, the following side of it being much more
strongly developed than the side preceding the spot.

The impending disappearance of the latter has been
suggested by several observers from its loss of tone during
the last few years, but there seems to be no tangible
reason to suppose that we are on the point of losing this
truly singular object. It is indeed utterly impossible to
predicate anything definite as to its future history. The
facts gleaned during past observations are not of a
character to guide us to any reliable conclusion. Its
present fainlness may be but the prelude to a more

NO. I314, VOL, 51]

marked manifestation, for variation of tint is certainly one
of its leading peculiarities. It is doubtless the same
object as the the ellipse seen by Gledhill and Mayer in
1S69 and 1S70, and quite possibly the same formation was
figured by Dawes in 1S57 and in subsequent years. At
any rate the resemblance of the objects is eminently
suggestive, and altogether too sti iking to be disregarded.

About fifteen years ago the equatorial zone of Jupiter
exhibited phenomena proving it to be in a stale of con-
siderable activity. There were white and dark spots,
wisps of dark material, veins of bright mailer, and other
irregularities all in condition of rapid change, and impart-
ing a very broken and variegated aspect to the northern
side of the great southern equatorial belt. To day the
indications are essentially different. The light tint of the
equator seems pretty even, and exhibits few noticeable
irregularities. Precisely on the equator there is a dark
belt like a narrow pencil line, but it is not now continuous
right round the disc. The chief seat of energy appears
to have been transferred to the northern side of the
great northern equatorial belt.

Dark spots (some of them almost black, like satellite
shadows) and white patches, with oiher details of
structure, are plentifully arra\cd in the noithern equatorial
belt. The white spots I observed here in 1S85 and 1886,
and they have persistently maintained themselves ever
since. Their roiation period in 1SS6 was about eight

1S94 November 35, loh. qm., 10-inch 'rctlcctor, power 25.'.
Rcgi^in of Red Spot.

seconds less than that of 'the red spot, but in 1S90-91 1
found it only 26 seconds less. At present the period is
still a little less, and there are a number of black spots
in the same latitude, and subject to the same drift. One
of the most conspicuous of the black spots |)rccedes the
red spot about 3h. 20m , and one of the chief while spots
precedes the red about 2h. I have secured the following
observations of this pair of objects : —

niiick spot.

White spot.

Mid tr.ifisit.

Long.

Mid transit.

Lon;

■S94.

ti. m.

n

■893-

h. n).

0

Nov. s

... 10 57 ..

• 2391

Nov. 23

... 10 0 ..

3034

'5

9 10 ..

. 2382

1894.

«7

... 10 47 ..

• 2376

Nov. 5

... 12 16 ..

286 '9

29

... 10 39 ..

• 2377

'S

... 10 31 ..

287-2

Dec. 4

... 9 42 ..

■ 235-1

25

... 8 45 ..

287-0

18

... II 14 ..

■ 236 s

Dec. 19

... 8 24 ..

284-2

The northern temperate belt on which in 18S0 and
1 891 many rapidly moving black spots appeared, is now
in close contiguity with the gieat noithern belt, and
blends with it in certain places. A few years ago the two
belts were separated by a bright zone.

There is a narrow spotted belt in about latitude 35 north.
In 1892 and on subseciuenl occasions I noticed this belt
beaded with numerous dark spots, but I have not made
a sufficient number of observations to dcteiminc the
rotation period. This belt forms a delicate object ; it is
very narrow, and the spots extremely small. In bad air

January 3, 1895]

NATURE

12C)

it is quite obliterated. Only a few observers appear to
have noticed this northerly belt and its beaded aspect,
but it has been an interesting feature of the planet during
the last two years.

In the southern hemisphere and further south than the
red spot, there are some dark condensations and white
spots, with a rotation period of about gh. 55m. 20s.

The S. region of the great N. belt exhibits interruptions
in the form of very bright streams of material dividing
the belt in an oblique direction relatively to the equator.
These appearances show rapid changes from day to day,
and I have not yet computed the rotation period satis-
factorily, but it is obviously very different to that of the
red spot. Five observations of the^e luminous encroach-
inents on the belt have been secured here, as follow ; —

November S ...

Mid-transit.

h. m.

II 0

Long.
- 3320

IS ...

29 ...

December 4 ...

«2 3«

9 47

8 I

- 3597
... 2061

... 174-1

19 ...

■• •• 9 33

... 325-8

It is intended to make a closer study of the variable
aspect and rate of velocity of these singular formations.

We may depend upon it, from the number of interest-
ing markings displayed on the planet, that there will be
no abatement of useful observations during the present
apparition. There is always something new to record,
and objects previously known require attentive watching
with reference to the difterences in their rotation periods.
Whether the theorem that the longer an object remains
visible the slower becomes its velocity is true or not, can-
not be definitely said, but the behaviour of the red spot
has not altogether supported the idea. A vast amount
of new evidence is required as to the phenomena affecting
the surface markings of Jupiter ; he presents an ample
field both for the observer and the theorist.

W. F. Denning.

NOTES.

Science is represented in the list of New Year honours
■by Mr. W. H. While, C.B , F.R.S.,the Director of Naval Con-
struction, who has been promoted to a Knight Commandership
of the Bath. Two other Fellows of the Koyal Society, Dr. J.
Russell Reynolds, President of the Koyal College of Physicians,
and Dr. Eric Erichsen, formerly President of the Royal College
of Surgeons, have each had the honour of a Baronetcy conferred
upon them.

The cross of Commander of the Order of the Ernestine House
of Saxony, second class, has been conferred upon Dr. Edward
S. Ilolden, Director of the Lick Observatory, for his services to
science. This Order was founded in 1690, reorganised in 1833,
and is conferred upon persons holding high official positions,
■either military or civil. At present there are eighteen Com-
manders of this class in Germany.

The fund for the proposed statue to the late Dr. Charcot
•will probably soon be closed ; as it is announced that thirty-five
thousand francs have been collected, and this is sufTicient to
warrant the ordering of the statue. In all probability, a statue
will be erected to llelmhollz, for it is reported that, at the
recent celebration in Berlin, the German Emperor ofTered to
head a subscription list for that purpose with a donation of ten
thousand marks.

The Paris Chemical Society has (says the Chemist and
■Druggist) recently come into possession of a legacy from M.
Rigout, formerly of the Ecole des Mines, who bequeathed to

NO. I 3 14. VOL. 51]

the Society an income of twelve hundred francs per annum, of
which a portion is to be set aside for an annual prize to lie
awarded in connection with inorganic chemistry. M. Rigout
declines to allow his name to be attached to this legacy, but
asks to have it named the Edouard Kivot prize, in memory of
his former Professor. It is worthy of mention that a shor? time
ago M. Silva, late Professor at the School of Arts and Manu-
factures, left his library and modest for;une to the same Society
"out of gratitude for the kindness met with in the French
scientific world."

The death is announced of M. Frederik Johnstrup, Professor
of Mineralogy in Copenhagen University, at seventy years
of age.

Dr. F. Kohlrausch, Professor of Physics in Stra^sburg
University, has been appointed Director of the Imperial Physico-
Technical Institute at Berlin, in succession to Ilelmholtz.

Increased facilities for instructing in the science and art
of agriculture are gradually being given to the Technical
Education Committees in various parts of the country. We
are glad to see it announced that Earl Cowper, chairman of the
Hertfordshire County Council, has offered to place a farm of
nearly 300 acres, with residence and buildings, a; the disposal
of the Council, rent free, for the purpose of providing practical
instruction in agriculture, on condition that the County Council
stock the farm and work it. Lord Cowper has also undertaken
to erect a laboratory and the necessary dormitories. A sub-
committee of practical agriculturists has been appointe.l to
consider his lordship's offer and report to the Council upon it.

A new society has just been formed in Paris for the purpose
of subterranean exploration, to be called " La Socic-ie de
Spelaaologie." Its projector is M. E. A. Martel, whose works,
" Les Abimes" and " Les Cevennes," may be familiar to some
readers of Nature. In his papers read before the French
Association for the Advancement of Science at Besancon in
1S93, M. Martel warmly set forth the claims of underground
investigation, and the light that might thereby be thrown upon
geology, palaeontology, and kindred subjects. Indeed, as
readers of the works just mentioned are aware, very interesting
discoveries have already been made, notably that of the under-
ground rivers of Bramabiau (Gard) and of Padirac (Lot).
Among those who have joined the Socieit; de SptJIaeologie are
several well-known men of science. All information is to be
obtained of M. Martel, 8 rue Menars, Paris.

The idea of holding International Mathematical Congresses
is crystallising into shape. Prof. Vassilief, of Kazan, has
suggested an assembly of mathematicians in 1896, in order to
definitely decide the organisation of such congresses. The
matter was pushed a little further at the Vienna meeting of the
Deutsche Mathematiker Vereinigung, in September last, when
it was unanimously resolved that the committee of the Mathe-
matical Union should take part in framing the necessary arrange-
ments ; and the .Mathematical section of the French Association
for the Advancement of Science have also expressed their sup-
port of the scheme. A circular now informs us that the Editors
of the Inleniu'Jiarc will be glad to receive the names of mathe-
maticians who are in favour of international meetings of the
kind suggested. M. C. A. Laisant's addreis is 162 Avenue
Victor-Hugo, Paris ; and that of M. E. Lemoine, 5 rue
Liltrc.

The Johns Hopkins University Circular states that it is
proposed to collect the physiological papers and addresses of
Prof. Martin, and publish them- as one of the memoirs of the
Biologic.il Laboratory of the Johns Hopkins University. This
plan h.is been adopted in response to suggestions from a number

NATURE

[January 3, 1895

of his former pupiU, that the long and valuable services of
Prof. Martin to the University, and his brilliant contributions to
American physiology and biology, should be commemorated by
a memorial of some kind. After consultation with a number
of his friends, it has been decided that the most appropriate
form of memorial will be the publication in a handsame volume
of his scientific papers and addresses. It is hoped to raise a
fund among his friends sufficiently large to meet the cost of an
edition of about 300 copies. One copy will be sent to each
person or institution subscribing ten dollars, and, if desired, an
extra copy for every additional ten dollars subscribed. As the
work will be placed at once in the hands of the printer, it is
requested that subscriptions be sent promptly to Prof. W. H.
Howell, Johns Hopkins University, Baltimore.

There are often hidden me.inings in the humorous answers
given by schoolboys in the examination room. From a
collection of such answers in the University CorrtsfouJent, we
cull a few authenticated specimens. " Parallel straight lines,"
said one boy, " are those which meet at the far end of infinity."
And another sagely remarked that "Things which are
impossible are equal to one another." The boy who wrote
"A point i> that which will not appear any bigger, even if you
get a magnifying glass," would have no difficulty in under-
standing that a star, being but a lucid point, cannot be
magnified. Every examiner is familiar with the noncommittal
answers frequently received, and with which may be classified
the cautions statement that " Two straight lines cannot enclose
a space, unless they are crooked." But even these words of
wisdom are eclipsed by the definitions of kinetic and of
potential energy once received. " Kinetic energy," ran the
definitions, "is the power of doing work. Potential
energy ii the power of doing without work." This truth,
which has a monetary application, is well worth adding to
our contemporary's collection.

A SWARM of bees in December is remarkable enough to be
put on record. According to a Long Sutton (Lincolnshire)
correspondent of the Daily Telegraph, a few days ago there
was a swarm of b:es on a farm at Spalding, Sutton Crosses.

Though the present age is not very favourable to the de-
velopment of pure science, applied science nourishes like a green
bay tree. An instince of this growth is afforded by a note
from the Institution of Civil Engineers, with reference to the
present membership. The Institution, which was established
in January 181S, and incorporated by Royal Charier in June
1878, for the general advancement of Mechanical Science, now
consists of as many as 6660 members.

IMMKDIATRLY following the recent very high barometric
pressure, which reached 30 '93 inches on the west coast of
Ireland on December 27, a large disturbance advanced over
the northern parts of our islands from the Atlantic, and during
the night of the 28lh, destructive gales from \V. and N.W.
were experienced over the whole country, accompanied by
snow, thunder, and lightning. In some districts the storms
lasted for •'cveral days, and were followed by sharp frosts,
generally. At Greenwich a wind pressure of 28 lb. on the
square foot was registered on Saturday morning, this pressure
being one pound less than in the severe storm of the previous
week.

In Natiinviiienie/ia/ltich Wochen\ehrifl tot December 9,
Dr. C. Hess discusses the hailstorms of Switzerland for the
years 1883-1893, on the basis of the observations regularly
published by the Meteorological Office at Zurich. He finds
that hail is more frequent in the valleys than on the mountains,
the latter at timei transforming the hail into sleet, ur rain.

NO. 1314. VOL. 51]

Near marshes, and in the valleys of the lakes, hail occurs more
frequently than over woo led country, while the river valleys
which lie in the direction of the paths of the thunderstorms
favour the formation of h.iil. On passing over a cultivated
district or a hilly forest, there is, however, a tendency to a
decrease in the intensity, and, at times, an entire cessation of
the hailstorms.

The prize offered by the Hon. Ralph .\bercromby for the
best essay on "Southerly Bursters" (NATttRE, vol. xlviii, p.
77> has been awarded by the Royal Society, N.S.W., to H. A.
Hunt, of the Sydney Observatory, and the paper has been pub-
lished in vol. xxviii. of the Jjurnal of the Society. The essay,
which extends to forty-seven large octavo pages, and is
illustrated by four photographic plates, contains a short note on
"bursters" in New South Wales and other colonies, and gives
tabular statements of all that have taken place at Sydney
between September 1S63 and March 1S94. These storms occur
very suddenly, and mostly between November and February ^
a fresh north-e.isterly wind may change in ten minutes to a gale
from the south, doing much d.image to vessels that may be un-
prepared. The storms are always accompanied or preceded with
great electrical excitement, and cause a considerable drop in the
temperature. The wind velocity used to reach from 60 to So
miles an hour, and on one occasion attained the rate of over 150
miles in the hour, in a gust. Latterly, however, the wind
seldom exceeds 50 mile.*, and generally ranges between 20 and
40 miles an hour. This result possibly arises either from ob-
struction to atmospheric disturbance by increased number of
buildings, or from less absorption or radiation of heat, owing to
greater cultivation of the land. The average annual number of
storms is thirty-two. The investigation is the result of much
patient research, facilitated by reference to unpublished
documents to which access was allowed by the Government
Astronomer of the Sydney Observatory.

We are informed that one of the points in the Report of the
Upsala meeting of the Inlernalional .Meteorological Committee,
contributed by Mr. Lawrence Rolch to the Aiiicricaii Meteorolog-
ical Jounial, and reprinted in Nature of December 20, is mis-
leading. It was stated that " aproposition of the Russian Ad-
miral Makaroff, on the necessity of an international convention
to arrange for the discussion of the data contained in ships' logs,
was not approved." This is erroneous, for we understand that
Admiral Makaroff did not ask the Committee to express an
opinion upon his scheme, so the subject was not discussed at all.

The significant name " Pilhecanthropiis ereettis" is proposed
by Dr. Eug. Dubois.'of the Nethcrland-Indies Army Service,
for some fossil remains recently discovered in the andesitic tuffs
of Java, as indicating the former existence in that island of an
intermediate form between man and the anthropoid apes. The
bones, which consist of the upper part of a skull, a very perfect
femur, and an upper molar tooth, are elaborately described and
figured in a quarto memoir recently published at Batavia.

Till, announcement that the Surinam water-toads, recently
received by the Zoological Society, have commenced lo show
the curious phenomena of their reproduction, in the Reptile
House, has created much interest amongst zoologists. There
can be no doubt that one of these living specimens now carries
a layer of ova placed in cells in the skin of its back, and that
about eighteen days after the deposition of the ova, young tad.
poles were visible in some of the cells. Thus the extraordinary
facts recorded by Madame Merian, concerning the reproduction
of this abnormal Batradiian in the latter part of Ihe last century,
and not, wc believe, subsequently noticed, have been already
partially verified.

January 3, 1895]

NATURE

Dr. Anton Reichenow, of the Royal Zoological Museum
of Berlin, has just completed a memoir on the birds of German
East Africa, which will form a portion of the third volume of
Stuhlmann's work, " Mit Emin Pascha in's Ilerz von Afrika."
The memoir gives an account of 728 species of birds which have
been recorded up to the present time, by German naturalists
and other explorers, as met with within the limits of the German
Protectorate. The remaining portions of the same volume,
which are in progress under the editorship of Dr. Mobius, will
complete the account of the vertebrates. The fourth volume,
under the same editorship, will be devoted to the invertebrates,
and the fifth, edited by Dr. Engler, to the botany of the
German East-African Protectorate. Vol. vi. will give an
account of the geography and meteorology, and vol. vii. of the
geology and mineralogy of the same country. It may be asked
how long we shall have to wait for a similarly complete account
of British East Africa ?

The "Zoological Record" for 189J, which has just been
published by Messrs. Gurney and Jackson, for the Zoological
Society of London, has appeared rather later than usual.
Its bulk shows us at once that the quantity of work accom-
plished by zoologists in 1893 is not inferior in amount to that
■of the immediately preceding years. Some of the recorders,
we may be allowed to point out to Dr. Sharp, commence their
" Records" with an interesting account of the principal events
that have taken place in their special branches of the subject
during the year of record. Others altogether neglect this very
desirable piece of information. It would be well to insist that
a page or two of introduction, containing matter of this de-
scription, for the general information of zoologists, should be
prefaced to every section of the "Record. ' Many readers who
clo not care to study the special portion, would like to get a
general notion of what has been going on.

A.N' exhaustive bacteriological investigation of the AUona
water-supply has been recently published by Dr. Reinsch.
Although the results obtained are not specially novel, yet they
are of importance as confirming the researches of other investi-
gators. It is pointed out that whilst the layer of slime which
forms on the surface of sand-filters plays an important part in
the retention of microbes, yet another factor must be most care-
fully watched if a satisfactory filtrate is to be obtained. This
factor is the depth of the column of fine sand through which the
water is made to pass. It was first called attention to by Dr.
Percy Frankland in 1886, in the course of his examinations of
the London water supply ; and since that time investigations
made at Zurich and elsewhere, have shown that it is not advis-
able to reduce the layer of sand below 30 cm. Reinsch states
that it should never be less than from 40-60 cm. high. This
investigator also states that to encourage the formation of
surface-slime, the filters, after the water is first run on, should
be left undisturbed for twelve hours, and that the neglect of
this simple precaution exercised an important influence on the
filtrate.

Some vexed points in the developmental history of medusje
have been attacked in a masterly manner by Miss (?) Ida II.
Hyde, who publishes a paper on this subject in the Zeilsihrijl
f. win. Zoologie (\ii. Iviii. iv.). The material for her investi-
gations consisted of embryos of ihree different species of Auic/ia
and Cyaiiea. The formation of the endoderm is shown to vary
considerably in difierent species and even in the same species.
In A. mar«inaUs the endoderm is formed by multipolar
delamination, in C. arctica by delaminalion at the pule of the
blastopore. In A.flaviJula the endoderm sometimes arises by
embolic gastrulalion, with or without the participation of a few
immigrant or delaminated cells, but in other cases arises almost
MO. 1314, VK.. si]

exclusively from immigrant and delaminated cells, the invagin-
ated element being relatively insignificant. These differences
of origin in the same species seem to be determined by local
conditions of temperature and salinity of the water. The
author regards multipolar delaminalion as the most primitive
of the various processes by which the endodermal digestive
chamber is brought about. The development of the Scyphuta
larva is then traced, and the author is able to confirm Goette's
account in all essential points. There is a true stomadxum,
and the invaginated ectoderm also takes part in the formation
of the four septa and of the gastral filaments of the Scyp/iosloma.
The points of affinity which have been raised between the
Scyphomedusas and the Anthozoa thus acquire new and
substantial support from Miss (?) Hyde's researches.

A NEW periodical, Archiv fiir Entiuic kelitngsmechanik Jtr
Or'anismen (Leipzig: Engelmann), of which the first number
lies before us, is intended by the editor. Dr. W. Roux, to pro-
vide a medium for the publication of researches upon the causes
of the phenomena of organic development, as distinct from the
mere normal order of the phenomena themselves. The journal
is to furnish an organ for that branch of biology which has
been variously termed the " mechanics of development "
and "causal or experimental morphology." In the hands of
Roux, Driesch, Hertwig, Chabry, Wilson, and others, the
methods of this school, which are above all things experimental,
have been applied to various problems in development with
much success and with the most interesting results. It is there-
fore to be hoped that the publication of a journal specially
devoted to experimental morphology will lead to a considerable
increase in the number of investigations in this promising field.
In the present number the editor gives an introduction on the
objects, methods, and scope of the branch of biology the new
Archiv represents, and a number of interesting researches are
published on the " cytotropism " of isolated blastomeres, on
compensatory hypertrophy of organs and regeneration, and on
the origin of the forms of joints.

The young cocoa-trees in one part of the island of Jamaica
are suffering from the attacks of a caterpillar. A correspon-
dent calls our attention to a letter in the Jatnaica Gleaner, in
which Mr. W. Fawcett, the Director of Public Gardens and
Plantations, regrets that the museum is at present without the
services of a curator, who might be able to give some informa-
tion as to the best means of dealing with the caterpillars, and
the remedy he suggests for keeping down the plague is by hand-
picking. In this connection, a summary of a report on a plague
of caterpillars at Hong Kong, in the current Kezu Bulletin, is
of interest. These caterpillars appeared on pine-trees, and
belonged to a large moth (Metanastria punctata. Walker).
The trees attacked were those of Pinus sinensis. Lamb, very
largely planted in the island for re-foresting purposes. Active
steps were taken by the Government to destroy the pests, by
establishing stations where the caterpillars could be received
and paid for by weight. The caterpillars were caught by
shaking the trees and picking them off the ground. From the
report summarised in the A'eiu Bulletin, it appears that the
plague lasted two months. The quantity of caterpillars col-
lected weighed nearly thirty-six tons, and a large number of
cocoons were also destroyed. .Altogether it is estimated that
thirty-five million insects were destroyed. Mr. W. J. Tutcher,
who drew up the report, says that the methods employed for
the extirpation of the scourge were decidedly successful ; so that
if similar measures are promptly taken at Jamaica, the cater-
pillais may be kept under.

In measuring the volume of a solid by immersion in a liquid,
it is usual, after withdrawing the solid, to find what volume of
liquid is required to re-establish the former level. The well-

232

NATURE

[January 3, 1895

known difficulty of identifying the former level is overcome by
Sgr. Goglielmo in a manner described in the current Atti del
Linen. He grinds the edges of a beaker, and mounts inside it
a pointer of glass or platinum so that iis line point lies just in
the plane of the edge. This is accomplished while the mount-
ing cement is still soft, by inverting the beaker on a plane
surface, and thus pressing the point into its place. A burette
with an india-rubber tube enables the observer to add or
withdraw a known volume of water. In order to measure the
volume of a solid, the plane horizontal edge of the beaker is
lightly spread with grease or paraffin, and the beaker is filled
up until the unevenness in the liquid surface produced by the
pointer has just disappeared. A volume of water larger than
the solid is then withdrawn, and the latter is immersed. The
liquid is then brought up to the point again, and the difference
of level in the burette is the volume required. The rttlection of
the bar of a window or other straight line in the liquid is
useful for discovering any deformation of the surface. If the
pointer should not be easily wetted, a few drops of soap
solution are recommended, or the substitution of petroleum for
water.

The comparison of condensers of small capacity and the
measurement of the specific inductive capacity of liquids is of
considerable importance. An interesting paper on this subject
was read by Prof. Nernst, of Gultingen, before the German
Electro-Chemical Society (see also /.eilschrift J'nr Physikilische
Ciicmie, vol. xiv. p. 622), in which he describes a method for
measuring the specific inductive capacity and specific resistance
of liquids. The author uses a modification of De Santy's method,
in which a telephone is used in place of a galvanometer, alter-
nating currents supplied by a small induction coil being used.
The resistances employed in the bridge must necessarily be
non-inductive, and also, since the capacities to be compared
are very small, of practically evanescent electrostatic capacity.
Mence the author uses liquid resistances contained in fine cap-
illary tubes, the electrode at one end consisting of a fine plati-
num wire, which can be moved along the bore of the tube by
means of a micrometer screw, and thus the resistance of the
liquid column be varied at pleasure. An air condenser is used
as a standard with which to compare the condenser containing
the liquid under observation, and when this liquid is not a
perfect insulator the telephone cannot be brought to com-
plete silence by altering the resistances. To overcome this
difficulty the author places a high resistance shunt on the air
condenser, which is adjusted so that complete silence is
obtained.

A SYSTKM of two pendulums joined by an elastic thread has
been studied by M. I.ucien de la Rive, and the results of his
experiments are given in the yonrnal de Physique. The
masses and the lengths of the twj pendulums were ^equal, and
the elastic threads consisted of pure unvulcanised caoutchouc,
long enough to make the amount of stretching small in compari-
son with their length. It was found that there was a periodical
transmission of energy from one pendulum to another. On
starting one pendulum, and arranging the thread so that it
always remained stretched, the other pendulum started swinging
with increasing amplitude, until the first was for an instant
reduced to rest. .Vfter that the second pendulum was gradually
reduced to its minimum, which did not, however, attain zero,
while the other reached its maximum. This transmission of
energy exhibited a fixed period, which could be derived from
the ordinary period of each pendulum by multiplying with
a number proportional to the length, and inversely pro-
portional to the sectional area of the thread. In the end,
the pendulums tend to oicillatc like a rigid system, with a
constant tension of thread, .\fler ten or twelve oscillations,

NO. 1314, VOL. 51]

the alternation of periods is hardly perceptible. When one
pendulum only was attached to a fixed point by an elastic thread,
the decrement was observed in order to determine the internal
friction of the thread. This internal friction gives rise to an
elevation of temperature which has been exhibited by Warburg,
who placed india-rubber tubes round glass tubes containing
sounding columns of air, and observed the rise of temperature
in the caoutchouc. It shows an analogy to that in wires due to
electric currents.

Ox October 27, as we have recorded in a previous number
(p. 18), a disastrous earthquake occurred in .\rgentina. The exact
time is as yet unknown, and it is therefore uncertain whether
any connection exists between this earthquake and a remarkable
series of pulsations that were registered on the same day in
several European observatories. At Rome, a very slight and
comparatively rapid movement of the great seismometrograph
(length, l6m., mass, 200 kg.) commenced at gh. 7m. 35<:., p.m.
(Greenwich mean time). This lasted until gh. 40m., when the
slow pulsations began to be visible. The first maximum occurred
at 9h. 49m. 50s., and the principal one at 9h. 55m. 40s. The
amplitude then rapidly diminished, with occasional maxima,
the disturbance lasting until about It p.m. Pulsations were
also recorded at about the same time at the geodynamic observa-
tories of Siena, Ischia, Pavia, and Rocca di Papa. The period
of the complete oscillations at the time of their maximum ampli-
tude was found to be 167 seconds at Rome, and about 18
seconds at Siena and Rocca di Papa. In the south of Russia,
at Charkow and Nicolaiew, horizontal pendulums were strongly
disturbed. K\. the former pl.ice, the movement began at
gh. 8m. 363., p.m., and, for more than an hour, was so great
that all traces of the i>hotographic curve disappeared. The
large oscillations lasted until lib. 9m. 48s., and the small ones
until oh. icm. 54s. a.m., of the following day. At Nicolaiew,
the disturbance was first perceptible at 9h. 12m. 6s., p.m., and
the curve disappeared almost completely between 9h. 24m. 6s.
and loh. 2m. 6s., the pendulum continuing in oscillation until
oh. 37m. 65., a.m., of the next day. The magnctographs at
Utrecht and Wilhelmshavcn also showed traces of the pulsations,
at the former place beginning at gh. 45 m. 28s., and reaching a
maximum at 9h. 56m. 2Ss., at the latter beginning at
gh. 5Sm. 25s. and ending at loh. iim. 55s. No disturbances
are perceptible on the magnetograms at Lisbon, Perpignan,
Paris, Kew, Greenwich, Stonyhurst, Vienna, and St.
Petersburg {Boll. Meteor., Suppl. 112).

The last issue oi Studies from the Yale Psychological Labora-
tory contains an interesting record of Dr. Gilbert's researches
UQ the mental and physical development of schoolchildren
between the ages of six and sevenlpen years. On the physical
side, statistics are given of increase in (a) weight, (//) height, and
(<) lung-capacity. On the psychological side, there are observa-
tions on the development of the power of perception and dis-
crimination as exercised upon (a) weights poised in the hand,
(l>) colour-dilTerences in a scries of shades of red, and (c) time-
intervals. To these are added observ.itions on the "force of
suggestion," in which, by means of a seiies of lo.tded blocks (l)
of different sizes but the same weight, and (2) of different sizes
and different weights (the two being nowise correlated), it is
shown that visual perception of size very markedly affects
weight-discriminations. Reaction time, with and without dis-
crimination and choice, was tested ; and observations were made
on the influence of fatigue on " voluntary motor ability " as
measured by the rapidity of tapping with the key of a specially
devised piece of apparatus. In all cases the results, both for
boys and girls, are summarised in curves on the graphic method.
One of the interesting features to be noticed in these curves is the
influence of puberty on mental development, there being a

January 3, 1895]

NATURE

^11

marked depression in the curves at the age of from thirteen to
fourteen years. Another noteworthy piece of work, recorded in
the same number, is that by Dr. Scripture and Mr. H. F. Smith,
which deals with the highest audible tones. The general result is
that the pitch of the highest note varies directly and almost pro-
portionally with the intensity. It is also shown that the limit
of audibility is much higher when reached by descent from more
rapid inautlible vibrations, i.e. proceding from silence to sound,
than it is when reached by ascending from less rapid audible
vibrations, i.e. proceding from sound to silence.

The ninth part of "The Natural History of Plants "—the
English edi' ion of Prof. Kerner's admirable " Pflanzenleben "
— has been published by Messrs. Blackie and Son.

Messrs. A. a.nd C. Black have published the hird part of
" .V Dictionary of Birds," by Prof. Alfred Newton, F.R.S. The
part extends from " Moa " to " Sheathbill." We propose to
review the complete work when the fourth (and last) part has
been issued.

"Webster's Practical Forestry, "published by Messrs.
Rider and Son, has reached a second edition. We reviewed
the work when it first appeared (Nature, vol. xlix. p. 526),
and it is only necessary to add to the remarks then made that
the author has enlarged the volume, thus increasing iiS value
as a prac'.ical and popular handbook on the rearing and growth
of trees.

The secon 1 volume of Mr. Bjulenger's "Catalogue of the
Snakes in the British Museum," which has just been issued,
concludes the account of the Aglyphodont Colubrine Snakes,
and gives descriptions of 427 species, which are represented in
the collection by 252S specimens. We understand that the
MS. of the third and concluding volume of this important work
is nearly ready for press.

The December number of the Journal of the Royal Micro-
scopical Society has just been received. It contains a paper by
Mr. F. Chapman, on the Foraminifera of the Gault of
Folkestone (part vii.), and a description of a simple method of
measuring the refractive indices of mounting and immersion
media, by Mr. E. M. Nelson. The invaluable summary of
current researches in zoology, botany, microscopy, &c., takes
up the chief part of the journal.

We note the commencement of vol. xxx. of the meteorological
publications of the Manila Observatory. The Bulletin for
the year 1894 is in a large quarto form, which is much more
convenient in size than its predecessors. In addition to a good
summary of the weather over the Philippine Islands, the work
contains hourly observations for Manila, and observations taken
twice daily at a number of secondary stations, together with
rainfall and other maps.

Messrs. Whittaker and Co. will issue the first number of
a new science weekly on January 5. The new journal will
embody the combined features of The Technical World 3.nA
Science and Art, two periodicals which have hitherto appeared
as separate organs. It will appeal to all persons interested in
the progress of art, science, and technology from an educa-
tional point of view. In addition to current news, the journal
will contain articles in all the departments of pure and applied
science and art.

A FINE geological map of Alabama, drawn on a scale of an
inch to ten miles, has been prepared and issued by the Geo-
logical Survey of that Slate. The map is accompanied by a
very useful explanatory chart, showing, in four parallel columns,
(l) the names, synonyms, classification, and common fossils of
the formations ; (2) the thickness, lithological and topographical
NO, 13 14, VOL. 51]

characters, area and distribution ; (3) useful products ; (^4)
soils, characteristic limber growth, agricultural features. By
means of this chart and the coloured map, the geological record
of Alabama can be read by any one.

We have received from Dr. A. von Danckelman, an excerpt
paper from vol. vii. of " Mittheilungen aus den deutschen
Schulzgebieten," containing some valuable meteorological
observations made by Dr. Steinbach, during the year 1893,
at Jaluit, an island in the North Pacific. The station is situ-
ated in 5' 55' N. lat. and 169' 40' E. long., and is only five feet
above mean sea-level. .\ Richard barograph was sent out by
the Deutsche Seewarte in 1S92, but the vessel was wrecked on
approaching the island ; another was supplied, and records were
commenced on January I last. The observations for 1893 show
that the air temperature is exceedingly uniform, the yearly range
only amounting to 22' ; the absolute maximum was 92'''8 in
November, and 70°7 in September. Cloud is very prevalent^
there only being six clear days during the whole year. Rain
falls almost daily, there being 343 wet days during 1893, the
total fall being 1S2 inches ; the greatest fall in twenty-four
hours was 45 inches. Thunderstorms are not very frequent ;
there were only thirty-two in the year in question, but it is note-
worthy that the majority occur in the forenoon, to an extent
which h.is, we believe, not been observed at any other station.

The additions to the Zoological Society's Gardens during the
past week include a Bonnet Monkey {Macaciu sinisus) from
India, presented by Mr. J. Hussey ; two Red-eared Bulbuls
{Pycnonolus jocosus) from India, presented by Brigade-
Surgeon Lieut.-Colonel E. F. Drake Brockman ; a Cape
Bucephalus {Bucephalus capensis), a Rhomb-marked Snake
(Piaininophylax rhombcatus) horn South Africa, presented by
Mr. J. E. Matcham.

OUR ASTRONOMICAL COLUMN.

A New Short Period Variable. — The possible variability
of d Serpenlis was suggested some time ago by the Potsdaui
photometric work, and the variation has now been confirmed
by Mr. Yendell {.Istronotuical /ournnl. No. 331). Fifty
observations made by him between August 5 and November 4
of last year indicate a variation from magnitude 50 to 5 '7
in a period of not far from S'7 days. The form of the light-
curve appears to resemble that of 3 Lyr.T;, though this is not yet
certainly established. There appear to be two maxima, one at
2'2 da)s, and the other at 6'2 days from the principal minimum,
while there is a secondary minimum of about magnitude 5 '5 at
4'3 days from principal minimum. Mr. Yendell suggests the
provisional elements

1894, August 76 (G.M.T.) -!- Sd.7 E.

The new variable is chiefly of interest in the prob.ible resem-
blance of its light-curve to that of fl Lyra;. Notwiihsl.'inding
the very detailed investigations of the spectrum changes in the
latter \ariable, which have been recently made at Harvard,
Potsdam, Pulkowa, Stonyhurst, and Kensmgion, the cause of
the variaLility is by no means completely understood. In this
case the spectrum is a complicated one, consisting of bright
lines as well as dark ones, and the Kensington photographs
have shown that there .ire two dis'.inct sets of the latter.
.\ccording to the Draper catalogue, however, the spectrum of
(/ Piscium is of the Sirian type, and no mention is made of
bright lines. It may be that a complete study of the simpler
spectrum of this star will throw some light on the origin of the
variability in 18 Lyue, and possibly also on the causes which
produce other kinds of continuous variability in shoit periods.

The position of the star for 1900 is

R..\. iSh. 22m., Decl. + o' S'.

Doppler's Principle. — The verification of Dopplei's prin-
ciple has hitherto depended upon comparisons of iliespectro-
scopically measured velocities in the line ol sight of Venus, and
of the sun's limb with their kiiown velocities, and upon the

234

A\^ TURE

[January 3, 189 =

consislency uf the measured velocilies of stars when due allow-
ance is made for the varying effect of the earth's movement.
Dr. Belopolsky, however, has recently suggested a method
(Aitr. Nice. No. 3267^ of demonstrating the principle by a
laboratory experiment. Imagine two cylinders with axes
parallel, on which are arranged vertically two sets of small
coirrors, .2, /, . . . ., in, 11, o . . . The mirrors are inclined
so thai a ray of light falling on ,; is relltcled to m, back again
to l>, then to »/, and so on, finally being directed to the slit of
the spectroscope. If now the cylinders be set in rapid rota-
tion, in opposite directions, the elTects of the mirrors will be to
accelerate or retard the velocity of the ray of light accorditig to
the directions of movement. Figures are given which indicate
that measurable displacements may be obtained by employing
cylinders of from 025 to 07 m. diameter, with ten or twenty
mirrors, making from eighty to twenty revolutions per second.
With cylinders half a metre in diameter, making eighty revolu-
tions per second, and having twenty minors, the equivalent of
a velocity of five kilometres per second in the line of sight is
obtained, and with modem instruments there would be no dit'li-
cnlty in observing the eft'ects of such a movement. It is pointtd
out that dynamos already make from seventy to eighty revolu-
tions per second, and if sufficient care be taken in the construc-
;ion of the cylinders, the experiment does not seem to present
in.-uperable difhculiies.

" The .\STROPHVSiCAi. Journal." This is the title under
which Astronomy and Aitro-Phyiici will appear in future. The
University of Chicago has purchased that journal, and arrange-
ments have been made to carry it on under the editorship of
Profs. Hale and Keeler, assi.-ted by Profs. .\mes, Campbell,
Crew, Flos', and Wadsworih, anda number of associate editors,
five of whom represent Germany, Great Biitain, France, Italy,
and Sweden. The scope of the new publication will be quite
as broad as that of Aslronotny and A>tto-Fliyiics, for all
problems and investigations of modern physical astronomy will
be dealt with. The journal will, in fact, represent the common
ground of physics and astronomy, and it should therefore be
appreciated ly the ph5sici^t as much as by the astronomer.
Workers in astronomical physics should be gratified that their
science has progressed sufficiently to need a special organ m be
devoted to its interests. Fcftilar As/roiumy will be continued
as heretofore, and will appeal to all amateurs, teachers and
students of astronomy, and others interested in celestial science.
This journal will be practically the old Sii/ciail Afescii^-ci\ and
the Aj!ivf!:yiica.' joiiriial \\\\\ he the realisation of Prof. Hale's
original plan of a periodical for workers in the domain of the
new astronomy.

Elliptical Oriuts. — A little pamphlet on elliptical orbits,
by Mr. H. Larkin, has been published by Mr. Fisher Unwin
If it should induce any student o( astronomy to ronstruct for
himself the curves in which the apparent 01 bit of a binary star,
as we see it, may be resolved, it «ill serve one useful purpose,
and probably ihe only one. Fur it is to he hoped that the same
student will not embrace the theory of lotmalion of binary stars
as given here, wherein they are made to result Iroui the explo-
sion of one larger star. There are manyothtr strange things
taught, of which Newton never dreamed, and which no one
capable '^f reading Newton would ever have slated. Perhaps
the most singular is the suggestion of " precarious equilibrium "
that would accompany motion in a circular orbit. " Precarious
equilibrium " is a curious term, but the context seems to sug-
gest that some catastrophe or disaster would result from such a
condition. The auihor does not seem to have realised that
there is no sudden and violent change between an ellipse of
small eccentricity and a circle, and that in the solar system
there are instances in uhich the eccentticiiy (if existing) is so
slight th,'\t the motion can be conveniently considered as
circular.

rOKESTRV J.\ NATAL}

"^ATAL lies between Inlitude 28 and 31' S. The climate
''' of the coast i< almost Iropiml, owing to a waim current
from Ihe equator. Mangrove dees g-ow along the coast, and
sugarcane and tropical Indian fruit ireeii are cultivated there.
The land ascends rapidly inland, and the capital, Pieter-

'I' ' l>t Sir Ditliich llrandi-, KC.I.E., F.K.S., in tlia

Fen

S'K 1314, VOL. 51]

Marilzburg — or Maritzburg, as it is usu.ally called, at fifty miles
from the co.ist — is at 2275 feet above sea-level, and possesses an
appreciably mild climate.

The colony is bordered on the west by the Kathlamba or
Drakcnsberg, a mountain chain attaining altitudes which exceed
9600 feet, and separating Natal from the Transvaal, the Orange
Free State, and Basuloland. These mountains form the
eastern boundary of the high South .\frioan plateau, which is
drained by the Orange River and its tributaries.

Natal is scantily populated, containing 18,755 square
miles, with 532,000 inhabitants, of wliom 38,000 only are
Europeans. Most of the latter are English who came by sea
and founded Port Durban, but a few are descended from the
Dutch Boers who came from the west in 183S-42 and founded
Marilzburg. Natal has been an English colony since 1843,
when the territory only included 3000 native inhabitants, but
their numbers rose rapidly to 100,000 in 1S45, and to 400,000
in 1SS3. They are mostly Zulus in the north, and Kaffirs in the
south of the colony.

Much greater progress could have been made in Natal, in
trade, agriculture, and manufactures, if it had been connected
by roads and railways with the Transvaal and Orange States.
The Cape railway, 65omiles long, from CapeTown to Kimber
ley, with express trains doing the distance in thirty-six hours, ha^
long been constructed, and in 1S93 this raihv.ay was extended
(0 the Transvaal gold mines at Johannesberg.

In iSSo a railway was constructed from Durban to Maritz-
burg, but only recently has it been pushed further inland, and it
now reaches the confines of the'colony. Its further extension to
Johannesburg is most important for the future prosperity ol
Natal. About one and a half years ago a railway was made
from Ladysmith in Natal to Harrismith in the Or.ange State.
Natal is at present short of funds, and this may partly explain
why, having made a good start in forest conservancy, the Colonial
Government has not had the resolution to persevere in it.

The Cape Colony has had for some time a good foresi
administration which was organi.sed by a French forest
ofiicer, Count Vasselot de Regne-, Conservator of Forests in
Algiers, and Mr. D. E. Ilutchins is now Chief Conservati 1
of Forests at Cape Town. He was trained at Nancy for the
Indian forest service, and left it for seiv'ce at the Cape in 1SS3.
Mr. Fourcade, of the Cape forest service, was employed in Natal
for nine months in 1SS9, and has written a very valuable paper
on the N.-iial foresis, but he declined to quit the Cape service
permanently for that of Natal, and was succeeded in 1891 as
chief forest oflicer there by Mr. Schopllin, a liaden forest
ofiicer.

The work he undertook of organising a forest deparlmeat
in Nal.al W.-IS full of difficulty, especially as the forest revenues
weic not expected to cover the expendiuire for a number of
years. Irrespectively of the continual clearance of forests for
the extension of agriculture, forest fires, unregulated gr.n/.ing,
and wasteful limber felling have so cxhausled ilie Natal forests
that the aieas still covered with brushwood and forest are widely
>caticrcil over the country, and only a small percentage of thetn
is still Siaic property.

From the coast to altitudes of about 975 feel, with an average
annual temperature of 67-71", the forest consists of numerous
species belonging to the tropical flora. The woods are not
more than 30 60 feet high, but something might be made of
them, as several species yield valuable timber. Unfortunately
nearly all the coast forests are now privale property.

In a central /one ranging in allituile between 980 and 34SO
feet with an average annual temperature of 59°- 67' F., exten-
sive tracts are covered with so-called mimosa scrub, formed of
seveial species of Acacia : these woods are very thinly stocked,
and contain a tall grass undergrowth. The acacias bear plenty
of seed, and young growth exists, but is continually being
destroyed by the annual grass fires. If only protection could
be afforded to these forests against fire, as has been done for
the last thiriy years in British India, they could be worked
prclilably with short ro'ations — twcniyfour years, according to
Mr. I'ourcadc ; it is, however, probable that most of this area
will be cleared for agriculture.

The present aica of the coast and acacia forests is estimated
at 196,000 acres of Suite forest, and 1,645,000 acres in priv.ite
hands.

In the higher zone, from 3450 feet up to 9600 feel, with
temperate climate, and an average annual temperature "i
52-59 , the most valuable foresis arc situated, but Ihey are

January 3, 1895]

NA TURE

^35

scattered over a difficult mountainous region. Of these forests,
the Stale possesses 54,000 acres, and 27,000 acres are in a terri-
tory assigned to the indigenous inhabitants of the country. The
Government has decided that in the mountains the action of the
Forest Department will be restricted to the Slate forests. They
contain many species ; Podocarpiis Thuttber:^ii and P. elongala,
both known as yellow-wood, are the commonest, and their wood
resembles that of the European spruce. At present the great
cost of transport prevents the profitable working of yellow-
wood. Amongst the remaining species, the two most valuable
trees are stink-wood {Ocolea buUatd)^ so named on account of
the bad odour of freshly-sawn wood, an evergreen iauraceous
species with a beautiful brown heart-wood, which is hard and
tough ; and sneeze-wood, PUroxyton tttiU, an ally of the horse-
chestnut. These woods are also highly esteemed in the Cape
' Colony, especially for cart and wagon making, and can be
■ worked at a profit even from these remote mountain forests.
I Unfortunately these two species are only found here and there
in the forests, and there is no large supply of them.

In the year 1891-92, the sale of wood by the Natal Forest
I Department yielded /'725, while the expenditure was ^1942,
I partly for establishment and partly for the survey of the forests.
Owing to the small area of forests available, and the remote
position of the State forests, Mr. Fourcade strongly recom-
mended that plantations should be started near the towns and
railways. Past experience with the blue gum (Eucalyptus
globulus) is favourable for the success of this tree in Natal. At
Arambi, near Ootacamund in the Nilgeri Hills in India, l^is tree
attains a height cf 107 feet in nineteen years, and yields 8696
cubic feet per acre. This enormous production of 457 cubic
feet per acre annually was attained in latitude ri N. at an
altitude of 7426 feet above sea-level.

In the higher latitude of Natal, a similar climate to that of

Arambi is found at 2275 feet above sea-level, and, according

to Mr. Fourcade, mixtures of Eucalyptus globulus, lougifolia

and rostrata give an even higher yield near .Maritzburg than at

Arambi. Mr. Schiipflin doubts whether this will be the case ;

but, at any rate, the gum-trees will give a large yield, and if

, the wood were only tit for fuel a considerable pecuniary return

! would be obtained. Several of the gum-trees, however, yield

'splendid timber, and especially £. rostrata, the red gum of

Siiuhern Australia.

limber imports into Natil average in value ^180,000 a
'ye.ir, so that, as the indigenous lorests are small, much
subdivided, and unfavourably situated, the State is clearly
called upon to plant up a sufficient area of the .Stale lands.
Mr. Fourcade stales that the land necessaiy for these plania-
'tions can now be purchased cheaply, and Mr. Schopflin
c iiiiienced planting operations. This useful measure is now
al luloned, owing to want of funds, and the plants in the
Slate nurseries will be sold.

I Besides Eucalypti, several Australian acacias succeed

""'mirably in Natal^ especially A. dccurreus and viollissima :

: bark is rich in tannin, and a plantation of 1200-1500 acres

lese trees has been started by a private company. Near

neighbouring Transvaal gold-lields, .lustralian trees are

•■"Z, planted on a large scale to supply mine-props.

I he length of rails in Natal is about 625 mile;, and the
nnuntain forests will yield a portion of the necessary railway

;-lcepers. "S'ellow-wood must be kyanised, as has been done in
Ihe Cape Colony, and kyanising works can easily be established
1 n Natal, and wood from gum-tree plantations ought to supply
lit balance of the sleepers required.

II is evident that Natal cannot possibly prosper without a
Korest r)epartment, and the colony will have cause to regret
laving abandoned the attempt to form one, after such an
jxcellent beginning has been made. The Government wished
o retain Mr. Sch'jpllin's services up to March 31, 1S94, but
vould not undertake to employ him after that date. Under
hese circumstances, he was obliged to resign his appointment
ast September, in order to return to the Baden Forest Service.

W. R. Fisher.

THE FERTILISATION OF " LORANTHUS
KRAUSSIANLS" AND " L. DREGEI:'

j^IIE parasite Loranthus Kraussianus grows on the coast here

on the tree Chcrtacmc Meytri, and as three of these trees

;row within a short distance of my house, I have this season had

|. good opportunity of observing the rather curious mode of its

fertilisation. In the flower bud the corolla segments adhere
along their whole length, forming an upright cylinder, of about
an inch long, of red and white, thus getting the not inappro-
priate colonial name of ''lighted candles. " The flowers grow
in close umbels, so close together as to give quite a reddish
tinge to the host tree. After a little time five slits appear about
half-way up the upright cylindrical corolla, and these slits are
about one quarter the length of the cylinder. The anthers
occupy almost the extreme tip of the cylinder, and are pressed
against each other by the closed lube of the corolla (the cylinder
aforesaid), the actual tip being occupied by the capitate stigma.
If a needle be inserted into one of the slits of the corolla with
a downward movement, as if to seek the nectar at the base, it
causes the tube to split with some force, and at the same time
the anthers are quickly and forcibly released from their pressure
one against the other, and fly downwards violently, scattering
practically all the pollen they contain by the one movement ;
and at the same time the stigma, from being upright, springs
to an angle of, say, 40deg"ees on one side quite clear of the now
split corolla tube. I found by microscopic observations of a
number of stigmas just at this stage, that only in a small pro-
portion of cases (I only found one) did any of tb.e triangular
pollen actually reach the slignia by the act of explosion,
although the style was fairly thickly peppered. These flowers
are constantly being visited by large numbers of the commonest
coast sunbird (Citiiiyris olivaceous), a very active and hard-
working, though not very brightly coloured, member of the sun-
birds. A little quiet watching will show the birds at these
flowers splitting open flower after flower, and getting head and
bill covered with pollen in moving about, undoubtedly fertilising
the capitate receptive stigmas (in the receptive stage protruding
free from the corolla tube) of other and older flowers. After
seeing them thus at work, the question arose whether without
their aid the bursting of the flower happened. The negative
evidence was that although I had observed for many hours, I
never saw a simple flower voluntarily explode ; but to check this.
I put a net-bag over a small branch containing, say, 80 to 100
healthy flowers. I fou.id that when thus protected hardly a single
flower got to a further s:age than having the splits on the corolla
tube ready for the outside aid of the sunbird to enable them to
perform the next function, viz. explosion. Actually none ex-
ploded, :ind, as a consequence, not a single flower within the
b.ig set seed. They seem to be quite sterile without outside
help, the anthers dehisce, but at a level below the capitate
stigma, and as the corolla tube is generally upright the pollen is
lost even as a self-fertilising agent. After careful watching, I
feel sure sunbirds are the only eflTeciive agents in the fertilisation
of this plant. At first I never observed bees visiting it, and
actually made a note to the efl^ect that they did not do so ; but
at a later date they came in good numbers. They seemed
simply to follow the birds, and take any nectar left by them in
the exploded floHer=, and very seldom, and then, I think, only
by a happy chance themselves caused the explosion. I did not
observe any other insect visitors, so that it would appear this
plant is dependent on C/«/y'W..; and there is an element of irony
in it, for from the berries of this plant the boys make bird-lime,
and the energetic efforts of these lovely little birds are towards
the perpetuation of the means by which they are often made
captive. It would be interesting to know how far the dift'erent
individuals of Loranthus on the one tree are in the position of
independent individuals of terrestrial species (pollen from an
iiiiiepciuUut individual being necessaiy lor the most perfect re-
sults of cross-fertilisation), or whether the fact of having a
common host approximates them in this respect to the position
of one plant, and whether to get the best results of cross-
fertilisation pollen should be brought not from flowers of a
diflerent individual on the same host,but from plants growing on
a different tree altogether. To carry on the life-history of this
pUnt, my friend Mr. Harry Millar, of Durban, informs me that
the berries when ripe are taken by the little tinker bird (Bar-
betula pusilla), who eats the coveriii<; oi ^.hs berry, and rejects
the seeds and viscid matter around them, and to cle.ar away the
latter bangs the berry with his bill against a tree, where the
seeds adhere with the viscid substance and germinate. I may
say that Mr. Millar states th.it in shooting these birds, as speci-
mens, he often finds the head and bill covered with pollen. _ I
am informed that another sunbird (Ci««jr;j Vtrreau.xi) \-h\ls
this plant, but as it is of the same habits as C. olivaceous, the
results of its vi^ils, as far as iheplaht is concerned, would be the
same.

NO. I3I4. VOL. 5 l]

2.36

NATURE

[Januaky 3, ibigs

Loranlhus Dregei grows on the coistUnds of Natal
upon various ho5is, most commonly perhaps upon the intro-
daced Syringa, Mclia Azcdarach, and n^-ver. so far as I have
observed, upon the tree {Clurtumi Meycrii) infested liy L.
KraussiJ''!!!. While in the bud ihe petals form a cylindrical
lube, and the anthers are pressed against the closed petals, the
tips being jast below the stigma. Subsequently sliis appear on
the still closed cylinder. My observations show that the plant
is abundantly visited by Citinyris olivnetiis and C. Verreaiixi
and that both birds insert their long bills into ihe slit to get
at nectar secreted at base of lube, exactly as in L. Kraussiaiiiis.
In this species, however, instead of the anthers remaining still
attached to the filaments when the flower jetks open, they are
all broken sharp off, and fly off into space wiih great violence,
parting with their pollen as they go. I find that although the
pollen is thrown so far upwards as to reach the base of the
stigma, the force appears so nic;ly adjusted that none actually
reaches it, the great bulk of the cloud of pollen being thrown
down* ar.ls so as to reach Ihe head and beak of the visiting bird.
Apparently after this dissemination of its pollen (and anthers)
the flower still has attractions for the sunbirds, (or I have seen
them distinctly visiting the burst flowers, and this would of
coarse be necessary if cro.^s-fertiiisation or, indeed, fertilisation
of any kind took place. And on opening the burst flowers I
found in most cises a quantiy of nectar, so ihat probably
secretion goes on after the flower is open and its anthers gone.
1 observed this plant repeatedly and at all hours of the day, and
never saw it visited by a single insect of any kind; and although
aware that negative evidence of this kind cannot be relied upon,
my ob3ervatii>ns were so frequent that I feel sure any insect
visilant>, at all even's diurnal visitors, must be exceedingly rare.
1 noticed one flowering upon Acacia sp. which was also in
flower and visited by bees, but the bees took not the slightest
notice of thefljwersof the L. Dregei. I should judge from
the length of the corolla lube, that il any insect visits this plant,
it must be furnished wilh a long proboscis, for ihe flower tube
from stigma to base is fully two inches long. As in L. Kraiis-
sianiis the fljwers need outside aid to burst at all, for I have
watched them for long periods and in all kinds of weather, and
never seen a single fl )wer burst by its own volition. Although
apparently entirely dependent on the sunbirds for its propaga-
tion, this mode of fertilisation must be very successful, for the
plant is very common indeed. In addition to the fact of Ihe
flying pollen never reaching the stigma, and self-ferlilisalion
being thus pieventcd, the flowtrsctnis to be piolcrandrous, lor
at astage ol development »hen a slight touch in the right place
bursts the flower, the stigma seemed dry and unrece|itive. After
bursting, the stigma, instead of being in line with the ciiolla
tuSe, inclines to one side, though not 10 such an extreme angle
as in /.. Araiusianm, and this deviation from the upri,;ht will
help })ollinalion to some extent. I have often watched ihe birds
on these flowers bursting them, and tach time causing quite a
little cloud of pollen and anthers to fly, and the force is so
treat, the anthers arc jeikcd 10 quite a considerable distance,
and in no single instance did Ihe lotce fail 10 detach the »h"le
of them. It is a vciy pietty and interesting sight. In the
cajc of this species, I believe it is absolutely dependent on
the sunbirds (or its sexual propagation.
Durban, Naial. Maurice S. Evans.

SCIESTIFIC IXVESTIGATION IX CANADA}
T N a Society formed to include as far as possible represcnta-
•^ live.* of all branches of literature and of science, it appears
lo be most appropriate that the president (or the time being
should dcvoic the adilros which il is his privdege to deliver, to
some specific topic, or lo the consideration ol such matters of
interest or iinpotiance as may lie particulatly in hi^own line of
woik or thought. The literary, artistic, and political develop-
ment of the country have already been dealt wilh. It may
therefore be of some interest and .service to give a very general
and very brief review of what has been accomplished, an<l what
remains to be accomplished in Canada, by various scientific
agencies working in the invciligation o( the natural features,
and towards Ihe development of (he natural resources, of the
counlry.

Science is but another and a convenient name (or organised

1 Abstract of an addrcsn delivered before the Royal Society of Canada,
b>- Ur. G. M Dawson. CM. O., K.R S.

knowledge, and as such it has entered so largely into every
branch of human effort, that when, at the present time, any one
allempts lo pose as a "practical," in contradistinction lo a
scientific worker, he may be known to be a rrlic of the past
age, in which much was done by rule of thumb ami without any
real knowledge of the principles involved. Neither can any
division be made bttween what is sometimes called " practical "
or "applied " science and science in general, for Ihe knowledge
must be gained before il can be applied, and it is scarcely yet
possible to bar any avenue of research with a placard of " no
thoroughfare," as an assurance that il cannot lead to any
material useful end.

At the same time, there are certain directions in which inves-
tigation is veiy closely wedded to results of immediate and
tangible value. Hut the line should not be too rigorously
drawn, for should the investigator for a lime stray into some by-
path of lesearch, because of his individual interest in his work,
il is not improba' le that he may return from his cxcursi.m with
some unexpected discovery, which may prove to have iniporianl
bearings on the problems of every-day life. Take, for example,
the slu ly of pala;onlology, which, relating as il does, to extinct
forms of life, might appear 10 be a branch of science wholly
removed from any practical object, however interesting il may
be lo disinter and to reconstruct these remarkable forms. Hut
we all know thai this study has become an indispensable one as
an aid lo the classification of the rock formations, anil thus to
Ihe search for Ihe useful minerals which some of ihese contain.
This is more particularly the case, perhaps, in the instance of
coal beds, which are usually confined in each region 10 some
set of strata, which may be defined with precision only by the
aid of the evidence aftbrded by fossil remains.

The Geological Survey.

In the firsi united Parliament of Upper ani Lower Canada,
in 1841, the Natural History Society of Montreal and the
Historical Society of Quebecj >ined in urging the establishment
ol a Geological Survey upon the Government, wilh ihe result
that the niodesl sum of ;{, 1,500 sterling was granted for the pur-
pose of beginning such a survey.

Mr. Logan, afterwards so well known as Sir William Logan,
was the fust geologist appointed. He entered upon his duties,
in iS4j,willi the greatest possible zeil, and forinorc than twenty-
five years the history of ihe Survey and that of its director were
the same.

The field work of the Geological Survey necessarily began
with exploratory trips in which the main feaUnes to beiieall with,
in a country almost entirely unknown geologically, were
ascertained. In many parts, even of Ihe ohier provinces, such
explorations are still requisite, but in most of these provinces it
became possible after a lime to proceed wilh the more sjstematic
mapping of definite areas, the map-sheets produced forming
parts of a connected whole. When the great western regions
weie added to the field, these could oi.ly be attacked by extended
cxploratoiy journeys in which geology and geography went hand
in hand. As il is now, the field woik of the Survey may be
divided under three classes: (l) Reconnaissance surveys; (2)
the approximate mapping of large areas on a small scale ; (3)
finished map sheets on a larger scale, and loiming continuous
series. All these three classes of work are in progress con-
currently in difteicnl districts, while the auxiliary chemical,
pala;oniological, and liihological investigations in the office are
kepi in touch with the field work, and render it possible to bring
this logelhcr in a homogeneous (orm. Were there in existence
any complete topographical majis of Canada, approaching in
accuracy 10 those which have been made in older countries,
much mote g-ological work could be accomplished wilh a given
amount of money and in a given lime, and thus the conslruction
ol such maps must be stated yet to l)e, as il has been from the
beginning of the Survey, one of the principal desiilerata. There
is, however, one other matter which at the pieseiit moment
must lie regarded as even more urgent, and one which might be
attained wilhina short time and at a relatively small cost. This
is the conslruclion of a suitable and safe museum building for
ihe preservation and display of the ini|>orlanl ciillection which
has grown up as the result of so many years of investigation.
This collcclion is not merely a matter ol rcc ird, closely con-
necteil wilh all the publications of the Survey, but il is fitted to
become also a great educational medium in regard to the
mineral resources of the country. With proper accommodation
its utility could be vastly increased for all purposes.

NO. 1314. VOL. 51]

January 3, 1895J

NA TURE

237

Nothing can be adduced which is more creditable to the
system ol j^overnment in Canada, than the quietly persistent and
uninierrupitd support acorded to the Geolojjical Survey by
every political party; but it remains to provide such a
museum builrling and cntre for the work as that referred to,
and it may t)<- confiden'ly asserteil that nothing would lie more
favourably recfived by the general public. This museum should
be of a naiiiinal character, and there is every reason to hope
that when it is undertaken, its plan will include provision for all
the valuable collections which have been or may be made by the
several Govtrnitient departments, so that it may form in effect
a represcniaiiun of ihe sources, the history and the various lines
of activity of the whole country.

Meteorological Service and Magnetic Observatory.

Although ihe first scientific branch of the Government service
established by Canada, it must be noted that several years pre-
vious to its inception the Magnetic Observatory had been
founded at Toronto. It was established as the result of
representations made by the British Association at its
meeting in Newcastle in 1S3S, acting in conjunction with
the Rojal S"Ciety of England, and as a part of a system
of ma>;netic research on .si-a and in the colonial pos-essions
of Gieii B i'ain. The observations were actually liegun in
1839. Meteorological observati-ms had been made concurrently
with tho-e relating to magnetism, from the time of the establish-
ment ol the observatory ; bur it was not until 1871 that the
Canadian Government first made a grant of 5000 do's, for a
meteorrrlogical service.

In 1876, the issue of daily weather forecasts and storm warn-
ings was bei;un, anr] since that time these have become so much
a pnrl of the every-day life of the country, ihat it is unnecessary
to enter into .iny explanriii -n of 1 heir character, or to present any
plea in their favour. They are equally imponantand necessary
to the farmer as to the navigator, and are, in addition, of value
in a hundrerl other ways.

There arc at the present time over four hundred stations in
Canada reporting to the central office, of which tweniy-nine
make daily telegraphic reports, useful primarily in affording
data for the wea' her forecasts. The meteorological service thus
develo])ed naiurally from the M ignetic Observatory, and both
have become merged in a common organisation, the growth
of the nielei>rolt)i^ical work n "W perhaps overshadowing the
original luagiielic puipose of the observatory in its immediate
interest, thou.h the importance of the magnetic observations
has never ticen lost sight of.

Respeciing majnetic charts of the Dominion, much also
remains 10 lie dime, for though scattered observations iT pre-
cision have been made, particularly in the west, no systematic
attemp' a' a magnetic survey has been un<lertaken since that
accomplished in an exieniled journey ihrough the northern parts
of the country in 1842 and 1843. hy Sir J. II. Lcfroy. It is
well to remember that the magnetic pole itself is situated wiihin
the limits nf Canaria, and that problems of the greatest import-
ance, both from a purely scieniific and from a praitical point of
view, call lor solu ion by a syste-rjaiic study of its secular move-
menr, as well as of any chang-s in intensity ami dip by which
this may be accompanied. These are all strictly domestic
problems, and they should not be left for solution to enterprise
from abro.ad.

Experimental Farms.

This branch nf ihe public service was established as the result
of the recommendation of a select committee of the Ilou^e of
Commons apfHiinted in 1884 to inquire into the best means of
encoura.dng and developing the agricultural resources o( Cana-'a.
The " Expi-rimen'al Farm System Act" was passed in 18S6,
and the orgnni-ati'm of the work began in the smie year

It is iluis only about eight years since ihe initial steps in this
new scieniific t-ntfipnse of the Government wee taken, but in
that time, thanks to the energy anrl aluliiy of the director and
staff of the farms, great progress has been made, anrl the way
has been opened in many liirections lor -till furll er usefulness.
Besides the ceniiai 'arm at Oitawa, which was first undertiken,
branch (arms have lieen esialilished for the mariiime pro-
vinces, M mitoba and the north-west territories, and British
Columbia.

If any line can be dra>«n between that which may be
lescribefi as siricily praciical and thai which may be called
purely scien'ific vv<irk, ii will he found to run through ihe
centre ol the field of operations of the experimental farms. An

NO.

I3I4, VOL. 51]

inspection of the reports already published will show that the
work consits largely of sul>mitting actual observations in the
field to scientific tests, ami in the application in turn of Ihe
best results of scientific knowledge to matters of eveiy-day
importance on every farm throughout the land.

The following are among the many lines of work undertaken
in this service : —

One is the origination of new crosses or hybrids of cereals,
fruits, and other u-eful plants to meet the requirements of the
varied clima'es and conditions of different parts of Canada.

Other branches d( the work involving much original research
arc : the investigation, by chemical analysis, of soils, in their
relaiion to fertilisers, and of grains, grasses, fodder plan's and

0 her products of the farm, by which a fundamental knowledge
of their respective value and of the best and most profit:ibIe
methods of their treatment may be arrived at, and the study of
insects and parasitic plants injurious or beneficial to vegetation
and to stock, such as to enable the pests of the agriculturist to
be combaieil either by nieihods which may be classed as direct,
or hy means wh ch are indirect. The la ter implies a study of
the life-his'ory of the forms to be dealt with, including not only
those which are native to the country, but those also which may
be from lime to time introduced, such as the Colorado potato
beetle, the horn fly, and many others. It includes also the
study of the be t means of counteracting the attacks by all those
lower forms of vegetation, known as ru-t, smut, mould or
mildew, that prey upon the plants which are the special care
of the farmer.

Even in connection with the familiar and almost wnrld-oM
operations of butler and cheese miking, the results of purely
scieniific investigations are now being proved to have a great
importance. The best mechanical methods of deal ng with the
milk from which these are made, are not here referred to. but
the fact that the nature of the vegetable ferments which act
upon this milk and upun the cheese, after it has been produced,
are now known to give character to the product ; that is to
say, the effect ot inoculation of the mass with some particular
species ol ferments is favourable, while the presence of others
is deleterious. Thus the results obtained in the whole licld of
bacteriology are being made contributory to the success of the
dairy. Already in Uenmaik " pure cultures " of certain kinds
of ferments are beginning to be regarded as necessary to the
success of the butt r-inaker, and essays of a similar kind are
actually in progress here.

It is not possible to refer in detail to the numerous experi-
ments and tests, completed or in progress, of varieties of plants
and animals which may be already well known, but of which it
is desirable to asccr ain those best suited 10 the actual circum-
stances of the country. Nor is it possible to enter into (|uestions
such as the tests of fertilisers, the testing of the vitality of seeds,
or the propagation of irecs suited for planting on the plains of
the nori h-«esi. Though a part of the useful work of ihe farms,
these do not imply original research in the same measure with
those sul'jestsalrcady alluded to. Neither is this the time to dwell
upon the methods adop'ed of making the information gained
available to the public, such a- the publication of special
bulletins and repoits of progress, the <iistrii>ution of samples of
seed grain (which in 1892 reached the number of 30.000) and

01 young trees for plantations.

Befoie concluding this brief review of the several branches of
scientific research or work carried on by the Governmen', allu-
sion must be made to several comparatively late undertakings
of this nature begun under the auspices of the Departtneal of
Marine and Fisheries.

Under the name of the "Geoiglan Bay Survey," a hydro-
graphic survey of the Canadian portion of the Great Lakes
was begun in 1 883. and several excellent charts of the northern
part cd Lake Huron have already been published.

When the Briti-h Associ.ition met in Montreal in 1884,
a committee of that body, which had for many years
been engaged on tidal determinations, interesied itself in the
exiensi.in ni such oliservaiions to Canadian waters, anrl a joint
commiiiee of the .-V-sociation anrl of the Roval Society of
Canada was formed, by which the importance of such observa-
tions, made systematically and with moiiern appliances of
accuracy, was urged upon the Government. In 1890 a beginning
was made in this woik, and provision has since been m.tde for
its continuation and extension.

Another promising dci ariure is' the initiation of a scientific
study of that most imponant element in the welfare of the

2 -.6

NA TURE

[January 3, 189-

country, the fisheries. Much has already been done in
Canada in the miller of the propagation of food fishes but
much yet remain; to be done in investigating the conditions
of the fisheries of both salt and fresh waters, and it may no*
be anticipated that before many years an important basis of
fact will hare been built up upon this subject.

One important line of inquiry must yet be mentioned in
which no systematic beginning has been made, either under the
auspices of the Government or by any society or institution
especially devoted to it. This is the field of ethnology, which
in Canada is a very extensive one, and which calls for imme-
diate effort, inasmuch as the native races, with which this study
is concerned, .nre either rapidly passing away or are changing
from their primitive condition.

Ten years ago, the Council of the British Association
was so much impressed with the urgency of investigations
of this kind, that it not only appointed a committee to
deal with the subject, but has since given e.tch year a sub-
stantial grant from its own funds in aid of this work. The
Canadian Government for several years supplemented this
grant, and eight reports, filled with valuable observations on
the western tribes, have so far, as a result of this action, been
published in the annual reports of the .Association. It has been
decided, however, that the functions of the committee, with
the grant accorded by the Association, shall cease this year, so
that if further progress is to be made, the matter must now be
taken up by the Canadian Government. It is earnestly to be
desired that the Government may at least contemplate the at-
tachment, either to the Indian Department or to some other
department, of a properly qualified ethnologist, by whom these
investigations may be continued.

SOCIETIES AND ACADEMIES.
London.

Royal Society, December 6, 1894. — "Experimental Re-
searches on Vegetable Assimilation and Respiration. No. I.
On a New Method for Investigating the Carbonic Acid
Exchanges of Plants." By F. F. Blackman, B.Sc, Demon-
strator of Botany in the University of Cambridge.

This paper consists of a description of a complicated apparatus
for the estimation of very small amounts of COo, which is
especially adapted for biological research.

By its aid the evolution of C< >._, by a single germinating seed,
or by a small area of a foliage leaf, can be accurately estimated
from hour to hour without a break, for any desired time, while
for the same area of leaf the more active absorption of CO„ in
assimilation can be easily determined for such short periods of time
as fifteen minutes, and that at the same time separately for the
two surfaces of one and the same leaf area. Further, for the
purposes of this assimilation, air containing any proportion of
COj, however small, can be supplied continuously to the tissue
under investigation. The apparatus is practically in duplicate
throughout, and strictly comparative double experiments can be
pcrfoimed.

The experiments are carried out in a continuous current of
air at atmospheric pressure ; the actual estimation of the COo
is accomplished by leadingthis through barylasolution, of which
only a small quantity is used in each case, and the whole of it
afterwards titrated in iitii in the absorption tube, to which only
air freed from CO.. is otherwise admitted.

The following communication illustrates the applicability of
this apparatus to theinvestigatiun of minute quantities of carbon
dioxide :

No. II. "On the Paths of Gaseous Exchange between
.\erial Leaves and the Atmosphere."

CDiieliisicins. — (1) That if the amounts of CO, evolved in
respiration by the two surfaces of any leaf area be determined,
it will be found that there is a very close relation between these
amounts and the distribution of the stomala. In those Ic.tvcs
with no stomata on the upper surface, practically no COj is
exhaled from that surface, and all escapes from the lower sur-
face. When stomata occur equally on the two surfaces the
amounts of CO^ exhaled are equal on the two surfaces, and
so on.

(2) Similarly with assimilation, no CO.j is absorbed by an
aitomi'iferouH leaf surface, and when stomata occur on both
surf.ices, then the amounts absorbed follow the ratios of stomatic
distribution.

(3) Buussingault's experiments on the assimilation of leaves

NO. I314, VOL. 51]

with blocked stomata, which h-tve hitherto formed the mainstay
of the "cuticular" absorption theory, are completely viliateil
by having been performed in super-optimal percentages of CO.,,
Their interpretation is exactly the reverse of that usually
accepted.

(4) The exhalation of CO2 in bright light by a leafy shoot in
Garreau's well-known experiment, is not the expression of any
physiological truth for the leaf, but is only due to the presence
of immature parts, or of tissues not sufficiently green, or not
fully illuminated. Mature isolated green leaves fully illuminated
assimilate the whole of their respiratory CO,,, and allow none
to escape from them.

December 13, 1S94. — " The Influence of the Force of Gravity
on the Circulation." By Prof. Leonard Hill, M. B.

The chief results of the research are contained in the follow-
ing conclusions : —

(1) That the force of gravity must be regarded as a cardinal
factor in dealing with the circulation of the blood.

(2) That the important duty of compensating for the simple
hydrostatic effects of gravity in changes of position must be
ascribed to the splanchnic vaso-motor mechanism.

(3) That the effects of changing the position afford a most
delicate test of the condition of the vaso-motor mechanism.

(4) That the amount of compensation depends largely on
individual differences.

(5) That the compensation is far more complete in upright
animals such as the monkey, than in rabbits, cats, or dogs, and,
therefore, is probably far more complete in man.

(6) That in some normal monkeys over-compensation for the
hydrostatic effect occurs.

(7) That in the normal monkey and man gravity exerts but
little disturbing inrtuence, owing to the perfection of the com-
pens.itory mechanism.

(8) That when the power of compensation is damaged by
paralysis of the splanchnic vasoconstrictors, induced by
severe operative procedures or by injuries to the spinal cord,
by asphyxia, or by some poison such as chloroform or
curare, then the influence of gravity becomes of vital import-
ance.

(9) That the feet-down position is of far greater moment than
the feet-up position, because when the power of compensation
is destroyed the blood drains into the abdominal veins, the
heart empties, and the cerebral circulation ce.ises.

(10) That, generally speaking, the feet-up position occasions
no ill consequence.

(11) That the horizontal and feet-up positions at once abolish
the syncope induced by the feet-down position by causing the
force of gravity to act in the same sense as the heart, and thus
the cerebral circulation is renewed.

(12) That firmly bandaging the abdomen has the same effect.
While the heart remains normal, and so long as the mechanical
pressure is applied to the abdominal veins, the blood pressure
cannot possii>ly fall.

(13) That if the heart is affected, as by chloroform or curare
poisoning, the restoration of pressure is incomplete, and it is
possible that the heart may be slopped altogether by the inrush
of a large quantity of blood, caused by too rapid an applica-
tion of pressure on the abdomen. More work would be thrown
upon the heart than, in its impoverished conditioi;, it could
perform.

(14) That vagus inhibition and cardiac acceleration are sub-
sidiary compensatory mechanisms in the feel-up and feel-dowa
positions respectively.

(15) That chloroform rapidly paralyses the compensatory
va.so-molor mechanism, and damages the heart.

(16) That ether, on the other hand, only paralyses the com-
pensatory va^-o-motor mechanism very slowly and when pushed
in enormous amounts.

(17) That the vaso-motor paralysis induced by these ana:s-
ihetics lasts for some considerable time after the removal of the
an.TJSthelics.

(18) That chloroform can, by destroying the com])cnsalion
for gravity, kill the animal, if it be placed with the abdomen oa
a lower level than the heart.

(19) 'I'h.at elevation or compression of ihe abdomen imme-
dialcly compensates for the vaso-motor paralysis produced by
chloroform.

(20) That compression or elevation of the abdomen, coupled
with artificial respiration and with squeezing of the heart
through Ihe thoracic walls, is the best means of restoring an

January 3, 1895]

NATURE

239

animal from the conrlition of chloroform collapse. That these
results agree entirely with McWilliams', and are opposed to
tliose of the Hyderabad Commission.

(21) That the feet-down poiition inhibits respiration, and the
fecl-up position accelerates it.

(22) That these respiratory results probably depend upon the
stimulation of sensory nerve endings by changes of tension
lirought about by the .alterations of position, because the results
are abolished by dividing the vagi.

(23) That in the feet-down position the respiration is
thoracic in type, and the abdomen is retracted ; in the feet-up
position the respiration is diaphragmatic and the abdomen freely
expanded.

(24) That these types of respiration tend to compensate for
the effects of gravity on the circulation, for the retraction of the
abdomen in the feel-down position mechanically supports the
abdominal veins, whilst the thoracic inspiraiions aspirate blood
into the heart. In the feet-up position the full and free expansion
nf the abdomen withdraws all obstacles to the compensatory
liilatation of the abdominal veins.

In the last part of ihe paper the medical aspects of this
ri:iearch ate discussed. It is suggested that emotional syncope
i> due to paralysis of the splanchnic area, and a case is quoted
uliere compression of the abdomen immediately removed the
syncopal condition. The same treatment, or that of elevation
1.1 the abdomen, is suggested for conditions of shock, chloroform
cdlapse, and after severe haemorrhage.

linally, a parallel is drawn between some of the results of
this research in reference to monkeys and those obtained by
In. George Oliver on man, by measuring the diameter of the
r.vlial artery with his ingenious instrument, the arteriometer.

Physical Society, December 14, 1894. — Prof. W. E.
.■\yrton and Mr, II. C. Haycraft communicated a paper on a
studenls' simple apparatus for determining the mechanical
livalenl of heat. lilr. Haycraft, who read the paper, explained
ii the object at which the authors had aimed was the construe-
.. jii of an apparatus which could be placed inthe hands of junior
students, and by means of which a result correct within one per
cent, could be obtained, without the introduction of troublesome
corrections. The method employed is the electrical one, and
the measurements to be made are (l) the value of the constant
current passed through the resistance, as given by a direct-read-
ini; ammeter ; (2) the average value of the P. t). between the
terininals of the resistance, as given by a direct-reading volt-
meter ; (3) Ihe mass of water heated //;« the water-equivalent of
the containing vessel, resistance-coil, and stirrer ; (4) the rise of
temperature of the water ; (5) the time during which the current
is passed. Of these the measurements (i) (2) (3) can be effected
without the introduction of an error anything like as great as one
percent. The ca^e of (4) and (5) is different. The riseof tem-
|ierature, to be measured with accuracy, should be fairly consider-
able, a:id the same remark applies to the time of heating as
measured by an ordinary stop-watch. At the same time, if
these two quantities are made unduly great, there will be too
meat a ratio of heat lost to heat generated during the experi-
ment. The authors consider that, with a given amount of elec-
trieal power available, the best conditions will be obtained by
making the percentage accuracy of the temperature measurement,
tlie[>ercrntage accuracy of the lime measurement, and thepercent-
a:.;e of generated heat lost by surface cooling equal. Hence they
determine ihe mass of water to be used and the time of heating
which may be expected to give the best results. I he immersed
conductor is a strip of manganin about 0*25 inch wide, 003 inch
thick, and 5 feet long, which is bent into a series of zig-zags,
so as to I iin a kind of circular gridiron, the successive portions
of strip lyng all in one plane, and the whole being held rigid
by a SI rip of vulcanised fibre, to which each portion of the
strip is screwed. Another precisely similar grid is placed
3 inches below the first, and the two are joined in series, and
are mechanically connected together by thin vulcanite pillars.
The water is contained in a glass beaker of just sufficient
diameter 10 lake the framework of manganin strip. This latter
exposes a considerable surface (about 400 sq. cm.) to the water,
and is moved bodily up and down during the experiment, thus
constitu ing an efficient stirrer. To allow sufficient freedom of
movement, electrical connection is made by means of very
flexible leads, each made up ol about 210 thin copper wires.
The results obtained by .students for the heat equivalent of the
J watt-second have an average deviation from the mean, if several
1 experiments are made, of less than one-half per cent. ; and
Ihey agree with the best standard determinations within one

NvJ. 1314, VOL. 51]

per cent. Mr. Griffiths thought it inadvisable to provide junior
students with apparatus from which every source of error had
been eliminated ; they were thus led to underrate the difficulty
of an experiment, and the care required to obtain reasonable
accuracy. Prof. Carey Foster agreed, generally, with Mr.
Griffi;hs, and deprecated the use of direct-reading ammeters
and voltmeters in experiments of this kind. He thought it
preferable that a student should learn to reduce instrumental
readings to absolute measure fir himself. Prof. S. P. Thomp-
son dissented from the opinions expressed by the two previous
speakers, and thought it was an advantage to students to have
the use of direct reading instruments. Dr. Sumpner described
a simple method which he had employed for measuring the
mechanical equivalent of heat, and which depended on the
heating of a stream of water, as it flowed through a pipe con-
taining the current-conductor. Prof Riicker was inclined to
take an intermediate view of the questions that had been rai-ed.
He thought that students should take for granted as little as
possible concerning their instruments; but to verify every
point, even if practicable, would occupy a great deal of time
which might otherwise be more profitably employed. Prof.
Ayrton replied, and explained that the calibration of
ammeters and voltmeters would be part of the work
of a student at another pait of his course. — A paper
by Prof. Ayrton and Mr. E. A. Medley, entitled "Tests
of glow-lamps, and description of the measuring instru-
ments employed," was commenced by Mr. Medley, ihe latter
pan of the paper being held over till next meeting. The object
of the investigation was to find at what E. M.F. glow-lamps
could be most economically run. Too low an E. M.F. gives a
low efficiency, and too high an E. M.F. renders the lamps
short-lived ; so that there must be (for a given lamp) a certain
E.M.F. which is more economical 10 work at than any other.
It was also pointed out that, as glo.v lamps deteriorate and
become less efficient with use, it may be an economy to discard
a lamp before the filament actually breaks. The lamp is then
said to have reached the "smashing point." Accumulators
were used to drive the lamps, automatic apparatus being used
to keep the E.M.F. constant, and when a lamp filament Broke,
the (act was automatically recorded on a tell-tale.

Geological Society, December 19, 1S94 —Dr. Henry-
Woodward, F.R.S., President, in the chair. — The Lower
Greensand above the Athei field Clay of East Surrey, by
Thomas Leighton. This paper embodies the results of the
author's examination of the Lower Greensand of East Surrey
during the thcee years 1892-94. The area discussed in
the paper extends from Leiih Hill in the west to Tilburstow
Hill in the east; and the divisions of the Lower Greensand
chiefly referred to are those hiiheito known as the Bargate,
San.lgate, and Hythe beds. The author stated that the Lower
Greensand of East Surrey sho.vs that formation to consist of
beds de^iosited in a marine estuary or narrow sea, not far from
land and within the influence of strong currents, extending
geneially from N.W. to S.E., so that, without palxontological
evidence, no correlation of beds here wiih those exposed at
.Sandgate and at Hythe is possible. He arrived at this con-
clusion by following the outcrop of the various chert-beds,
which, alier Dr. G. J. Hinde [Phil. Trans. Koy. Sac. vol.
clxxvi. 1SS5), are accejited as of sponge origin (deep-water
deposits), and further by following the outcrop of the pebble-
beds, described by Mr. C. J. A. Meyer (GVo/. A/a«: for 1S66,
p. 15). — On the eastern limns of the Yorkshire and Derbyshire
or Midland coalfield, by W. S. Gresley. The author attempted
to throw light on the question of the easterly extension of the
Yorkshire, Derbyshire, and Nottinghamshire coalfield beneath
the newer rocks. He noticed the general trend i^f the strata,
the sizes of other British coalfields, the question of the origin
of mountains, straiigraphical considerations, and the faults of
ihe North ol England. — On some phases of the structure and
peculiarities of the 'iron ores of the Lake Superior region, by
\V. S. Gresley. The autbor has studied heaps of ore brought
from the region lying south-west of Lake Superior since 1S90.
He described certain structural features of the ore-lragments,
and discussed the evidences of mechanical movements and
chemical alteration exhibited by these fragments.

Chemical Society, December 6, 1894. — Dr. Armstrong,
President, in the chair. — The relative behaviour of chemically
prepared and of atmospheric nitrogen in the liquid state, by
James Dewar, F.R.S. — On the use of the globe in the study
of crystallography, by J. Y. Buchanan, F.K.S. — A new
method of obtaining dihydroxytartaric acid, and the use of

240

NA TURE

[January 3, 1895

ihi= acid a= a rMgent for so.l.um. by If. J. H. ^e"'""-
lh.= ac.d a^ ^S^^^ ^^^ Alfred C. Chapman. -Interaction

Essential oil

of I • 2JiVeiones with primary amines ottne
R' CH. NH. (>econd notice), by Francis K. In

general formula
app, F. K.S., and

W. B.' Davidson.— The isomeric

rnk.h;irn;;hTng.poinis.by R. Meldola, F.R S.. and F. W.
Streatfeild.-On the yejlow colojurins '"^'

dinitrodiazoamidohenzenes

F.R.S., and F. W.

matter of Sopfiora

/^/ratVa.'by Th. Edward Schunck, F.R.S.

Paris.

Academy of Sciences, Dec. 24. 1S94 -M- I-°p"y '" "'^
ch^r -oXn nvariant numbers in •hetheoryofalgebraica^^.ur-
r K. M r^il^M Picird —Di^pacement of carbon by boron

e on
mall

(lorivsiives but vield no acid or basic salts.
arreei^Irally \vell adapted for determining their mo.ecu
wxi.h." and hence ,ha valency of the contained metal icradic
rv'in'::;ro' a deteimination^of the yapou, den^^^^^^^
ylacetonate. it is found that glucinum is ct
le must be written Be O.-On ihe consUt

These derivatives

their molecular

ical.

mum

is divalent, and its

acetylacetonate. u .'*■""•- „ -On 'the constitution of the

oxide must be written fie O. ^^"^ '^"^"^ n luunel.-On the

re^Hic^^be'SE p'h' o'in^^^ O. Racoviua.-

^^'{^'dtelopme.t/^e^^y^^ ^ ^^7^^"
the Cirripedes, by M. A. ijru\ei. vj" > Weden-

ences between normal and enervated muscle by M. J^--."*^^"
sky -On the biological relations between Chdochyirnouv.U-
tLn, A. Prune,, a'nd the vine, by ^.^I'-^.^-^.^'J^t,

-:^^rh:!.o?:^h::^^c:-f;.!:rpl^ofj;^:Sooiero.

phyllum, by M. B. Renault.

,heo,herhand.-On the circulaj^^on of 0,^ lymph m^t^^^^
g;:Ki:rin^crc;i<^S^ere.es.ab,ishmLc^^ne-
vLds by M A. Millardet.-The Secretary announced thedeath
irP.' FVarcois Denza, Director of the Vatican Observatory
"died December .4).-The elements of the pl^net 1894 BE. b^
M T Coniel ProviM-mal elements for the planet BI, by .M.
Capon The plane. BE is the most favourably s.iuat.d among
The known planets, for the determination of solar parallax
planM BI is identical with (369) of the .-/""«"
5: V„-/...-Ob.erva,ions of Encke's comet and of the planets
BH and BI, made at Algiers Observatory, by MM. !>;»•;''""<>
and Sv.-Ohservations of Encke's comet, made ^t Lyons
Ob° erratorv by M. G. Le Cadet.-Observations of the sun.
™S L7ons1)bserva.ory durin, the third cpiarter of .894, b^
Ml GuiHaume.-On the problcmof three bodies M. F. S.acci

clillaVtention ,0 his paper^n thi. ^-^'^1 ^^\'^^J;;':^'';i,,:;
1874. He rematks that a paper of August 27 (ComfUs >^nJus,
45 ) "Sur la transformation des equations canoniques du

p oblOme des trois corps." is a ^'=P'°''"="°" .°f .^" ^^,^
l._.. _ p ,,lc nn ihe matter of a priority ciaim

g
The
du Bureau des

Elccuic Meters proposed : " .7 •.•"{.-;, ^\ _p„hecamliropiis

paper. — Remarks
made by M. O.
solution of
series, by M. R. Perri

on the matter ol a pn
Staude. by M. P. Staeckel -
numerical equations by means of

n._On a doctrinal point relative

holm).— Sur la Tr.ins. .

holm).— Suite onde Eleltromaencusche
Versiich einer Theoric
BcM eKlen KOpern : Prol
HimmelsRCvvolbes : _, , . ,
''sEL'/.:s'-E^;foh'nS?ed.>Ia.ax^^^^ J..n«.->o- (">? .S>'-<i).-9oo_4

Words, January (Isb'-'") , Vr„rn,.vl

of the Chemical Society, ""'"'^^ ((;"^7„ ^ Jicon imie Journ.,1, Pecem

liche Z ologie, Iviu Band, 4.Heia"" J. ■-- '-■ ' ' '-'"

bcr (MacmJlan).
Journal, Jaiii.ary

On the

recurring

to

Andrade.

On il

by M. Vaschy.

traversed by a

OSta
supp'

the theory of multiple integrals, by M. Jules , ,f.„ _
-On the ai^iua for l6 and .8 variables, by "• *• Lafay-
hr elecirosta.ic capacity of a line traversed ^y a c-rren
The capacity per unit of length of a cable
permanent current has the same sense as in
idly varying currents, it cannot be
sed that Ihe electric field admits of a potential, hetice the
notion of a definite capacity disaopears.-Electnc potent.a s
in a liquid conductor in uniform movement, by M. O.
Gou'c d2 Villemonice. At speeds of 33 »" 3^3 >""'• P"
Scond. .he uniform Movement of a liquid conductor liaversing
widecla« tubes of uniform secti -n. does not produce any
r;pec' able difference of potential '>e.«een two pomts^n he
Ifauid -E.pfrimenial researches on radiation at low lemptra-
nT« bv M Raoul I'iclet. This is an abstract con am.rg a
,er^;o?cu;v ss^o-ingthe variation of r-idiation with time
and a .li,cu,sion of the^e curves. -Contribution to ihe stu.ly of

&c ■ Prof A. RiRhi (ttol gna)-

:W; FilehnetBonn"-Blaclcie's Fir.t S.agc Maihe.na.ics.

zine. Janu.-ir^' (")S Strand).
-Sunda, Macazine. lanuar,- ll-b.srer)-.lournal
'""° '- '^ ■ -Zcils^hiiftlilr Wissenschaff
1 .mic Journal, Pec

CONTENTS. PAG«

Biological Lectures and Addresses. By E. B. P. . 2-7

Textbook of Agriculture • ' ,; Vj' f i 219

Ewing on the Steam-Engine. By N. J. L -•»

°"\ve°tte':h!nt ''iTasVeihaltniss der Philosophie zu der

empirischen \Vis-enscha(t von der Nalur . •

Moore: "Meteorology. Practical and Applied. -

\\Ws • ■ " The P^vince'of South Australia " . . •
SmUh V " Measurement Conversion Diagrams . .
Letters to the Editor:- p^,^.

"^'.^'r^rd^'p ^'sTRev^H^W. wltson, F R.S
Tlv Uirn ■■■— I''"-'" t:entral Aus.ialia.-Prof.

Ex

before Whether prepared from ferrous or ferric sal s, all con
before. All .are coloured. They form a series pa^alM

Baldwin Spencer

P..Uv,.n.ology it the Royal_Scliool of Mines.-Right

«°"- "'^ " "M::r;n:-Ri-ght Hon. Sir John

220

220
221
221

221

223

223
223

223
223

36 hours.

in from 10 10 30 muiulei.

Thi- reagent allows the dctcc-
'Ihe method of

Clberyaikeiin;;: particularly acetylace.one. form me

NO. 1314. '^'OL. 5']

_ F.R.S.

Eocene Fn.s.U at Murrer
.-.J^^^'^hf^obJ^cly'Kaphy-WiUia.^^^

J. Pope . . . ^ ■ •■ ■ ■ ■ ■ ■ 22J

" l-he /. .ological Record. -S.I'ace

Gravitation.-Dr J. i°\^-^^% vincent

°"^°" "f ■.h,Farth Bv Prof. John Perry,
On the Age of the Eartn. uy r j ^^

Jupit'lr^' i/iluslratid.) By W. F.' Denning '. . . • • 22!^

Notes • •

Our Astronomical Column :— ^ ,

A New Short Period Variable ' ". . 233

Doppler's Principle . ^34

7A,- AsliPfhyikal Journal ^34

Ell,,tical Orbits . ^ ■ ; pi^i,„- • ; ; ; . 234

?re'F7rt\LM"?n-;r/°L./..AV,»..V,"».

J)r.cri lly M.urice S. Evans . . ■
scientific InveMiKat.on in Canada. By ^^^

D-wson, C M.G, I" R =» 238

lrokn;Pam?brs':rnd"seria.s Received! ! i • • ^4°

and /..

Dr. G. M.

235

NA TURK

241

THURSDAY, JAMUAKV 10, 1895.

THE ORIGINS OF ART.
Pie Anfange der Kiinst. By Dr. E. Grosse. 301 PP- 32
figures in the text, and 3 plates. (Freiburg i.B. : Mohr,
1894.)

DR. E. GROSSE, in his book on "The Origins of
Art," has struck out a new and very promising
line of research. Other authors may hive woriced to a
limited extent at restricted aspects of the subject, or may
have theorised to an unlimited extent ; but no one has
-tudied the beginnings and evolution of the arts, with
such constant reference to what actually occurs, irrespec-
tive of what the arm-chair philosopher imagines might
have happened.

Dr. Grosse limits its present investigation not only to
primitive art, but also to the sociological aspects of the
science of art, not because he does not appreciate the
other aspects, but because he wished to deal the more
thoroughly with this particular problem. His main
object appears to be to show, as he expresses it, that '' art
does not serve only as a pleasant amusement, but for the
fulfilling of the most earnest and highest practice of life."
The book contains the following chapters: The aim
of the science of art ; the method of the science of art ;
Primitive folk ; Art, Decoration, Ornamentation, Repre-
sentation (sculpture and painting) ; Dancing, Poetry,
Music, and Conclusion. The method adopted is that of
comparative ethnography, and our author confines his
attention 10 the lowest and least settled peoples — to the
hunter-folk. In order to elimimte as far as possible the
secondary factors of race and climate, he studies the
condition of each art among the following peoples*
Australians, Mincopies(Andamanese), Bushmen, Eskimo,
and Fuegans, with occasional references to other
peoples.

Each of these chapters is treated in so fresh and sug-
gestive a manner, that one is tempted to quote largely ;
but a sum narv of the general conclusions will give a fair
idea of the scope of the book. The chapter on dancing
is particularly interesting, and the importance of the
dance in social evolution is clearly brought out ; no one
who has witnessed and s'udied various kinHs of savage
dances, ran fail to feel that they have a significance and
value which is entirely lost in the dances of civilised
people. ''The pleasure of strong and rhythmical move-
ments, the pleasure of imitation, the pleasure of
giving vent to the feelings, these factors," writes
Dr. Grosse, "give a complete and sufficient explan-
ation of the passion which primitive folk have for
dancing" At the sane time, he points out that the
occasional assembling for social dances induces co-
operation among loosely-connected hunier-folk. " It is
perhaps dong with war the one factor which causes the
members of a pri nitive group to vividly feel their
solidarity, and it is at the same time one of the best rre-
paratives for war. It is difficult to overestimate the
value of primitive dances in the culture-development of
mankind."

It is found that the artistic creations of the hunter-folk
have by no means arisen from purely lesthetic intentions,
NC. 13 15, VOL. si]

but they serve at the same time for some practical object,
and frequently this latter appears to be the chief motive.
Primitive ornaments are not originally and essentially
employed for decoration, but as significant marks and
symbols. In other cases the esthetic intention certainly
predominates, but, as a rule, it is only in music that it
appears as the sole motive.

Although artistic activity, as such, hardly anywhere
occurs at the lowest graies of culture, still it is every-
where recognisable, and essentially of the same character
which one finds in the higher grades of culture. Only
one art, architecture, is wanting among any of the hunter-
folk. Herbert Spencer suggested that the three main
groups of poetry — lyric, epic, and dramatic — were evolved
in the course of the development of the higher culture
from an undifferentiated primitive poetry ; but these are
already to be found in an independent position of their
own at the lowest culture grade.

Primitive art forms are constructed according to the
same laws as the highest creations of art, the great
Eesthetic principles of rhythm, symmetry, opposition,
gradation and harmony are etnployed by the Australians
and Eskimo as well as by the Athenians and Florentines.
The sensations of primitive art are narrower and coarser,
their materials are more scanty, their forms are poorer
and more clumsy ; but in its essential m itives, means,
and aims, the art of primitive times is one and the same
with the art of all times.

Dr. Grosse does not believe that racial character has a
decided determining significance in the development of
the art of a people at the lowest grade of culture, but that
the individuality of the folk, as well as that of indi-
viduals, continuously increases with the course of their
development. The uniform character of primitive art
is due to a uniform cause, and that culture factor is
the uniform character of the condition of life of the
hunter-folk, irrespective of race or latitude.

The particular kind of production of a people depends,
above all, on the geographical and meteorological con-
ditions under which they live. The hunter-folk have
remained hunter-folk — not, indeed, as the older ethnolo-
gists believed, because they were from the very beginnmg
condemned to stand still through a fauity disposition, but
because the nature of their native country prohibited
progress to a higher form of production. Herder and
Taine maintain that climate exerts a direct influence on
the spirit of a people and the character of their art ; but
Dr. Grosse claims to have proved that the intluence is
indirect— the climate commands the art through the
production. It is doubtful whether this can also be
proved for the art of the higher folk, since people pro-
vided with a richer culture have made themselves in
their production independent of the influences of climate.
The progress of culture emancipates the folk from a
slavery to nature to a mastery over nature, and one may
dare to assume that this also finds a corresponding
expression in the development of art.

There are no peoples without art, and even the lowest
and roughest races devote a great part of their time and
energy to art ; to art, adds Dr. Grosse (perhaps some-
what unjustly), which is looked down upon by civilised
nations from the height of their practical and scientific
acquirements, and treated mainly as an amusement ; but

M

242

NA TURE

[January io, 1895

from the standpoint of modern science it is incompre-
hensible thit, if such an immense amount of energy was
diverted from the conservation and development of the
social organism and devoted to aesthetic creation and
enjoyment, Natural Selection would not step in, and long
ago have rejected those peoples who wasted their energy
in so unproductive a manner, in favour of other and more
practically endowed folk. The conclusion is therefore
arrived at that, from the very beginning, primitive art,
besides its immediate aesthetic significance, must also
possess a practical advantage for the hunter-folk.

The primitive arts operate in very different ways on
primitive life. Ornament demands technique above
everything. Ornament and the dance play an important
part in the intercourse of both sexes, and through their
influence on sexual selection probably serve for the im-
provement of the race. On the other hand, some of the
arts increise the power of the social group in its resist-
ance to hostile attacks ; for example, certain decoration
is employed to frighten opponents ; poetry, dancing and
music stimulate and encourage the warriors. The most
important and beneficent effect which art exercises on
the life of the folk consists in the consolidation and
broadening of (he social relationship. Not all arts effect
this to an equal degree. While d.ancing and poetry seem
predestined to this through their innate peculiarity,
music is, from the same cause, almost quite excluded from
it. But the effect of the two former varies according to
the stage of culture of the people ; for example, dancing
loses its influence as soon as the social groups become
too large for them to be united in one dance ; and, on the
other hand, poetry has to thank the printing-press for its
incomparable power. Among the hunter-folk, dancing is
the most important social influence ; for the Greeks,
sculpture enbodied the social ideal in the most effective
form ; in the middle ages, architecture united souls and
bodies in the halls of their gigantic domes ; in the
Renaissance, painting employed a language which is
understood by all the cultured peoples of Europe ; and
in recent times, the reconciling voice of poetry rings amid
the clash of arms and the conflict of classes and peoples.
As science enriches and elevates our intellectual life, so
art enriches and elevates our emotional life. Art and
science are the two most powerful means for the educa-
tion of the human race. No pastime therefore, but an
indispensable social function is art, one of the most
effective weapons in the struggle for existence, and con-
sequently it must develop it-elf always more richly and
powerfully through the struggle for existence. Art is
a social function, and every social function must serve
for the conservation and development of the social
organism. But it is wrong to demand of art that it should
be moral, or, more correctly, moralising, for then one
demands that art shall no longer be art. Art serves social
interests best when it serves artistic interests.

From the foregoing account it will be seen that this
book deals largely with the sociological aspects of
.esthetics ; and it is not only a study of primitive art in
the widest sense of the term, but it is also a study of
some of the f.ictors of social evolution. It is certainly a
book which should be translated into English, in order
that it may obtain a wider circle of readers.

Alfred C. Haddon.

NO. f3I5, VOL. 51]

FORBES' S HANDBOOK OF MO.\KEYS.

A Handbook to the Primates. (Allen's Naturalists'
Library ) By H. O. Forbes. Svo. 2 vols, illustrated.
London : \V. H. Allen and Co., Limited, 1894.)

OF the series of which the present work forms a
part, five volumes have now made their appearance,
namely, one on Marsupials and Monotremes, one on
British Birds, a third on Butterflies, and the two now
under consideration ; while a sixth, on British Mammals,
is now in the press. In the three volumes previously
issued, it was found practicable to make use of the
original plates (with the addition of a few new ones)
from the old " Jardine's Naturalists' Library "; but those
in the volume in that series devoted to monkeys were
such grotesque caricatuies, that both editor and publisher
were soon convinced that their reissue was impractic-
able. Consequently, the plates (twenty-nine in number,
in addition to several maps) in Mr. Forbes's volumes
have all been prepared from entirely new sketches
from the pencil of Mr. Keulemans. Whether the
lithographers have been quite as successful with some
of these as they might have been, we think is
doubtful ; the colours in some instances being decidedly
too bright, while in others the execution is too coarse,
and not sul'fi riently detailed. .\s a whole, however, they
are very creditable, while some, such as the portrait of
the .Vyeaye, forming the frontispiece to the first volume,
are admirable specimens of artistic work.

In a series of volumes like those under consideration,
it can scarcely be expected that their respective authors
should undertake a detailed study of the skins and skulls
of each species they describe, as if they were writing a
museum catalogue. Nevertheless, we believe that Mr.
Forbes has done this in a large number of cases, and has
consequently been able to make some important identifi-
cations. He had a specially difficult task before him,
for several reasons. In the first place, there is no British
Museum catalogue of Primates since the small one pub-
lished as far back as 1870 by Dr. Gray, which is now, of
course, totally out of date ; and, secondly, the collection
of monkey-skins and skulls in the National Collection is
far from being anything near as complete as is desirable.
So that, even if the author went through the whole series
in the groups most retiuiring revision, it is improbable
that his conclusions would in all cases be unassailable.
It may be added that the British Museum collection of
monkey-skins consists largely of menagerie-specimens,
without properly authenticated localities, or without
specified localities at all ; the reason of this being the
well-known dislike of English naturalists and collectors
to shoot monkeys.

As against these drawbacks, Mr. Forbes had some com-
pensating advantages, notably the recent descrifition, by
Dr. Forsyth Major, of several new forms of Lemuroids,
both recent and fossil. Consequently, his volumes con-
tain descriptions of several forms which are not to be
met with in any other collective work on the subject. Not
the least interesting among these is the gigantic extinct
Lemuroid [Afej^aladapis) of Madagascar, which it is
possible may have been still living when that wonderful
island was first visited by Europeans.

Mr. Forbes follows the classification now generally

January io, 1895J

NA TURE

243

adopted by English zoologists, including the Lemuroids
in the Primates, and commencing his description with I
the latter, from which he ascends to the higher forms, i
As the volumes only bear the title " Monkeys" on their
covers, it will perhaps be a surprise to many of our readers
(as it was to ourselves) to find Man included in the second |
volume. AUhoutjh we were aware that miny zoologists j
regarded Man merely as a highly-advanced monkey, yet i
we believe this to be the first occasion in which he has
been termed a " monkey " pure and simply. We trust it i
may be the last. |

We do not propose to criticise any of the author's
views as to the limits of species or varieties, or enter into
any di cussion on the thorny paih of synonymy and the
identification of imperfectly defined species. And we
accordingly content ourselves with saying that his de-
scriptions are, for the most part, accurate and welUvvtitten,
and that these are enlivened, when occasion requires,
with interesting notes on the habits of some of the belter-
known species. We cannot, however, refrain from enter-
ing a protest against the "double-barrelled" system of
nomenclature (as exemplified in Tarsiiis iar^ius) the
author sees fit to employ — to our mind the most in-
elegant and absurd result of a slavish adherence to
priority.

An important feature of the work is the inclusion of all
the knuwn lorms of fossil Primates. It would, however,
have been better had the author consulted a text-book of
geology, as we should not then have been told that while
Lemuroids are met wiih in the (2uercy Phosphorites and
the Hordwell beds of Hampshire, yet (vol. i. p. in) "in
strata of Olii^ocent^ and older Miocene age no Lemuroid
remains have come to light in Europe." We have like-
wise some doubt as to the alleged Ungulate affinities of
the Tertiary Lemuroids referred to on [he page last cited ;
and, indeed, it seems to us incredible that an animal
whose position is admittedly in the Primates, can at the
same time be allied to such widely different groups as
the Ungulates and the Insectivores, although this is stated
by the author to be the case. One other criticism, and
we have done. On p. 217 of the second volume it is
staled that 10 the genus Siiiiia " has been referred a molar
tooth found in the Pliocene strata of the Sivalik hills in
India. Il is considered to belong to an Orang-Utan,
Sim/'a satyrus" We have the best reasons for believing
that the specimen in question is a canine tooth, and
likewise that the paleontologist who made the generic
determination would be surprised to learn that he had
identified it wiih a living species.

An especial feature of Mr. Forbes's work is the at-
tention paid to the geographical distribution o( the various
species and groups of monkeys and lemurs ; this part of
the subject being elaborately tieated in a series of tables
at the end of the second volume, supplemented by eight
coloured maps. The details here given will be extremely
valuable to all future studenis of distributional zoology.

The series of which these volumes form a portion, ought
certainly to have an extensive palnmage from those who
are interested in natural history from a popular point of
view ; while at least some of the volumes— and Mr.
Forbes's among ihe number — will be almost indispen-
sable to professed students of zoology. R. L.

* The italics are our own.

BIRDS OF THE WA VE AND WOODLAND.

Birds of the Wave atid Woodland. By Phil Robinson,
author of " Noah's Ark," &c. Illustrated by Charles
Whymper and others. (London : Isbister and Co.,
1894.)

N/T R. ROBINSON is probably the most popular
A living representative of a school of writers on
natural history, dating its origin from the publication,
fifty or sixty years ago, of Mr. Broderip's delightful
"Zoological Recreations."

Taking birds and beasts as texts for pleasantly dis-
cursive essays, in which field-notes, poetry, and folk-
lore rub shoulders with the latest conclusions arrived at
by the learned in laboratories and dissecting-rooms, he
and his fellows bridge the gap which separates the
writings of such disciples of Gilbert White as the late
Richard Jefferies, and "a Son of the Marshes," from
purely scientific works.

Anything which Mr. Robinson has to say of the animal
creation in fur or feather is sure to be pleasant reading ;
never more so than when he has at his elbow as adviser
on such mysteries as " the miracle of migration " the
young lady who wrote the preface to " Noah's Ark." A
book with his name on the back, and pictures by Mr.
Whymper between the covers, is certain to find pur-
chasers and readers to enjoy it. It is a typical Christmas
book, prettily got up, printed on good paper, " leaded "
with seasonable generosity, beautifully illustrated, and
edited, perhaps rather hurriedly, to be in time for the
Christmas market. We notice, for instance, that an
excellent sketch of partridges in a stubble field figures
in the list of illustrations as "grouse." Again, he tells
us (p. 93) that " once upon a time rooks were called
crows," and that " as the latter had very evil repu-
tations the former sufi'ered for it." He goes on
to give a piece of his mind to "the obstinate people
in the world who will not understand that it makes
any difference whether they use a right name or
a wrong one." On his very next page is a capital
picture of a couple of scaly-beaked rooks gossiping by
the nest in a rookery at bed-time, with the legend beneath,
" Croivs at Sundown."

The description of the thrush carrying its snails day
after day to the same stone for execution, and there
"building up in its own way a little shell midden, like
those which prehistoric man has left us of oyster-shells
and clams to puzzle over," is in his best style. But we
cannot help thinking that the cases must be rather ex-
ceptional in which the bird, " when driven by stress of
weather to the sea-shore, treats the hard-shelled whelks
just as it tieated the garden snails " ?

The pictures seem to us, almost without exception,
excellent, and are so important a part of the book that
" Birds of the Wave and Woodland," by Charles
Whymper and others, illustrated by the pen of Phil
Robinson, would have been a scarcely less appropriate
title than that which appears on the front page.

The influence of South Kensington is apparent inmost
of the pictures, and the only serious doubt which suggests
itself on putting down a very pleasant book, is whether
it might not have been belter, somewhere or other, to
have acknowledged that many (ten at least) of the best

NO.

1315, VOL. 51]

244

NA TURE

[January io, 1895

are copies, in some instances almost photographically
exact, of cases in the Natural History Museum?

Mr. Robinson has kept his best wine for the last. He
has seldom, if ever, written anything more fresh and
charming than the description, in his concluding pages,
of the voles and water-hens of the osier bed in which in
boyish days he dodged his hated enemy the keeper,
slipping once, as he tells us, when suddenly surprised,
into the water, and sitting there " like a coot with only
head above the surface, and that half hidden by reeds ! "
The boy is father to the man, and we can pay the writer
no higher compliment than to say he has proved himself
worthy of his parentage. T. D. P.

OUR BOOK SHELF.

Studies on the Ectoparasitic Trematodes of ynpan. By
Seitaro Goto, Rii:,akiishi. (Published by the Imperial
University, Tokyo, Japan, 1S94.)

This memoir extends to 275 pages, and is illustrated by
twenty-seven plates. The species on which these studies
were made, were for the most part collected by the
iiuthor himself, from various parts of the Japanese coast,
between the years 1889 and 1892. For the present he
omits the Gyrodaclylidas, as his investigations of the
anatomy of this group are not yet completed. After a
brief introduction, in which the method of preparation
is described, the details of the anatomy of the several
systems, as met with among the species of the ten genera
found in Japan, are given ; this is followed by some notes
on the habitat, powers of locomotion, food and coloura-
tion of the several forms, and then we have the sys-
tematic portion. IJy far the greater number of the species
were found attached to the gills of fishes, but several
live in their oral cavity, and some even on the outer
surface of their bodies. In one remarkable instance,
that of J rtstomum hiparasiticum, the worm was
found always attached to the carapace of a copepod,
itself parasitic on the gills of Thvnnus alhacora. The
"looping" movements observed by Haswell have been
often witnessed by Goto, sometimes they are performed
so rapidly in succession as almost to escape observation ;
lateral movements in some instances were noticed.
Whilst the greater number feed on the mucous slime of
their hosts, some were undoubtedly blood-suckers. In
the systematic description, attention is drawn to the
important specific characters to be found in the
"hooks" which are often present, near the posterior end
of the body. Thirty species belonging to the following
ten genera are fully described : Microcotyle, Axine,
Octocotyle, Diclidophora, Hexacotyle, Onchocotyle,
Calicotyle, Monocotyle, Epibdella, and Tri^tomum.
While none of the geneia are new, some of them have
emended diagnoses, and the information about the
various species included in each is brought wonderfully
up to date. Of the thirty species, all are described as
new; one, Diclidophora smaris, was found in the mouth
cavity of Smaris -iiult^aris, taken in the Hay of Naples ;
all the rest are from Japan. Owing to the often very
imperfect descriptions given by previous describers of
species, it is possible that some of those described by
Goto may on further investigation rank as synonyms,
but most of them are strikingly distinctive forms.
Octocotyle, Uiesing, and Diclidnplwra, Diesing, have
been combined by many in the genus Octobothrium, F.
S. Leuckart ; but the author gives good reasons why
Diesing's genera should be retained, characterising the
former genus anew. The author's drawings have been

NO. I315. VOL. 51]

beautifully lithrgraphed; the plates have been all executed
at Japan, and will bear comparison with anv similar
work done in Europe. A very complete bibliography
of the literature cited is appended. We veniure to
suggest, that it is a duty of all biologists to send copies
of their published writings to the Library of the Imperial
University of Japan, where they will be used and
appreciated.

Woman's Share in Primitive Culture. By O. T.
Mason, A.M., Ph.D. Pp. 2S6. (London and New
York: M.acmillan and Co., 1S95.)

Anthropology— the science of man — has been sadly
neglected in the past, but there are signs that it will be
more extensively studied in the future. We believe it
was a president of the Anthropological Institute who
pointed out, a short time ago, that while such societies as
the Zoological, Geological, Linnean,and others were in a
flourishing condition, the Institute which has for its object
the study of man had only a membership ot three or lour
hundred. This strange stale of things is ditiicult to
account for, though probably it is due to some extent to
the absence of ethnological material to work upon in the
British Isles. It is very well known th.Tt, in the l"nited
States, the Bureau of Ethnology publishes most elaborate
reports upon anthropological lopics; but the opportunities
for such study in America are far greater than they are
here. Prof. Mason is one of the foremost workers in
the field of ethnology understood in its widest sense,
and he is particularly qualified to trace the story of the
part played by woman in the culture of the world. The
volume in which he does this is the first of an anthro-
pological series intended for the intelligent reader, but
instructive enough to satisfy the student. The author de-
scribes the work of woman in all the peaceful arts of life,
and shows that the past achievements have had much to
do with ihe life history of civilisation. The book is very
well illustrated, and is a desirable acquisition to the
library of every one interested in woman's work. A
large share ot attention is given to women of .American
races ; but, as the author is curator ol the Department of
Ethnology in the U.S. National Museum, this might
have been expected.

A Text-book of Sound. By E. Catchpool, B.Sc. Pp.
203. (London: W. B. Clive, 1894.)

As an elementary text-book dealing with the physical
processes which cause the sensation of sound, we
think this deserves praise. It will certainly give the
student the knowledge required before the more elaborate
treatises can be read with profit. The author wriies as
a well-inlormed teacher, and that is equivalent to saying
that he writes clearly and accurately. There are
numerous books on arou-.tics, but few cover exactly
the same ground as this, or are more suitable intro-
ductions to a serious study of the subject.

Ottica. By Prof Eugenic Geleich. Pp. 576. (Milano:
Ulrico Hoepli, 1895.)

This well-constructed manual will compare favourably
with the best elementary textbooks of optics. It is
attractively designed, handy in size, and scicnlifii ally
arranged. First the phenomena and theory of refraction, '
relleclion, and dispersion are des.ribed : optical in- I
slruments form the subject of the second part of the i
book ; interference and dispersion the third part, and
optical phenomena ol the earth's atmosphere, the fourth
p.irt ; various inlcrcsling notes, and a comprehensive
bibliography, conclude the volume. The optics of
astronomical insttuments are treated much more fully
than is usually the case in elementary text-books.

January lo, 1895]

NATURE

245

LETTERS TO THE EDITOR.

[ The Editor does not hold himself reipotnible for opinions ex-
pressed by his correspondents. Ntither can he undertake
to return, or to correspond with the writers of, rejected
manuscripts intended for this or any other part of Nature.
No notice is taken of anonymous communications.}

On the Liquefaction of Gases — A Claim for Priority.

Ever since the year iSSj.I have been almosi uninterrufjledly
engaged in the examination of the behaviour of the so-called
(jermanent ga-es at very low le iiperatures. During the fir-.i
few m'lnihs I performed my experiments t gether with the laic
Prof. Wio .lew>ki ; afterwards, during a series of years, I was
alone; an I more lately, I went through several inve^-tigiti'ins
with Prof. Wiikuw^ki. The results uf my researche-. t published
in the PdIisH, French, and German languages, whiKt they were
going on; in the Reports of the Crac iw Acaleny, of the
Vienna .\ ademy, in IVicdemann s Annalen, and in the Comptes
rendus. My researches are thus well known lo the sciciciitic
world, and I may add, without boasiing, that they have been
acknowledged by learned men o( dilTerent nationalities ; they
were also known to Prof. Dewar, who repealed ihem several
times, and always confirmed my results — th')se, lor instance,
on the absorption spectrum and the bluish colour of liijuid
oxygen, and on the liquefaction of ozone.

Prof. Ucwar at fir t duly acknowledged those of my experi-
ments which he repeateil, but afrerwaids he changed his b -
haviour, and in the lectures which he gave in l.ie Koyal
Institution, and during which he liquefied lar^e quantities of
oxygen and air, he never again mentioned that his experinirnts
were merely repetitions of mine,performed and pu'ilislicd several
years before. This is, perhaps, the reas n why the hn^lish
public, which attended those lectures, grew convinced that the
liquelaction of oxygen, and other so-called permanent gases, lias
been achieved for ihe fist time by Prof. Dewar ; and it may be
that the Rumford medal awarded by ihe Royal Society to Prof.
Dewar, tor the labouis which I was the first boih to perform and
to publish, is due to those very lectures. That my labouis should
thus have been passed over in silence, is all the inoie astonish-
ing, because as soon as the description of my apparatus, serving
10 Uquely large quantiiies of oxygen and air, was published in
1890, I sent him a reprint of it fiom the Bulletin International
de V Academic de Cracovie. A brief report ot iheapparaius is
also cjniained in the Beiblutter oi Wiedemann (vol. xv. p. 29),
under the title, " K. Olszewski : Ubcr das Giessen de» flii^sigen
Sauerstoi't'i."

Tnere is here no space for me to enumerate all my
investigations as regards the liquefaction and solidincaiion of
the gases in question ; but I intend shortly to puolish 111 the
English language a more compleie summary of my works, by
which the English public will be enabled 10 see that only a
small part of the rest-arches which were performed bv Prof.
Dewar ought lo be attributed to hiiu. For the present, I will only
state that all ihe so-called permanent gases (hydrogen alone
excepted) were liquefied in quantity lor the first time by
me, and that I determined their ciiiical points and boiling
points ; that nitrogen, carbon monoxide, nitric oxide, and
methane were also solidified, and their Ireezing points deter
mined. By means of solid nitrogen I obtained the lo-^vest
temperal ure that ever has been both obtained and measured,
viz. —225". Many other gases and liquids were frozen, anii
their freezing pomts determined for the first lime by me. 1
must finally remark that I also gave public lectures on the sub-
ject in Crac*w ; the first in 1S90, during which I obtained, in
the presence of over a hundred students, 100 c.cm. of liquid
oxygen ; the second in July 1891, duiing the Congiess of l\»lish
Naturalists and Physicians, and then I obtained 2C0 c.cm 01
liquid oxygen in tiie |)res=nce of a good many nauralisls, and
showed its bluish colour and its absorption spectrum. The
only reason that I have never hitherto employed a larger
quantity of liquid oxygen or air than 200 c.cm. was the circum-
stance that this quantity was quite sufficient for my expert
ments ; for my apparatus can be enlarged at will without
changing anything in its construction. I have very often used
large quantities of liquid oxygen and air whilst aitempling lo
liquefy hydrogen, and to determine its criiical pressure, as well
as to inquire into the optical properties oi liquid oxygen, as is
proved liy the whole series of researches, performed together
with Prof. Witkowski. Charles Oi.sztiWSKi.

University of Cracow, Austria-Hungary, December, 1894.

I HAVE read the letter of Charles Olszewski, and but for your
courtesy in drawing my attention to it would have allowed it to
pass without notice. Considering the Koyal Society, in the
year 1878, awarded the Davy medal to Cailletet and Piclcl
lor their achievements of the liquefaction of ihe so-called
permanent gases, it is hardly likely I could put forward
in England any claim for such a re-ult. A reference to the
f'roceedtn^s of ihe Koyal Institution between the years 1878 and
1893 will be sufficient to remove the suggestion that the
apparatus I use has been copied from the Cracovie Bulletin of
1890. The work ol the late Prof. Wr oiilewski has been fully ac-
knowledged in England, and 1 am not aware of any injustice done
to Charles Olszewski on account o( the alleged omission of his
subsequent investigations from public notice.

James Dewar.

The Term " Acquired Characters."

I am afraid that as Sir Edward Vxy has endeavoured to show
that the explanation, given by -Mr. Gallon and accepted by me,
of the term " acquired characieis " is an absur.iity when applied
to the consideration of the question as lo whether those
characters can be Iransuiilterl by generation, I must proceed
to convict Sir Edward of a loose and unwarranied use of
language whilst availing himself of the plausible form of strict
logical statements. I am a liiile disappointed with the value
01 the results hitherto accruing from the interveniioa of high
judicial authority in a scicniific iliscu sion.

Sir Edward Fry asked for a tiefinilion of the term "acquired
characters." From the observations which accompanied his
request, it was evident that he wished lor a siatcment of the
meaning attached to the lerrii when it is either asserted or denied
that the acquired characters 01 a parent may be inherited by its
offspring.

Mr. Fiancis Gallon gave (and I accepted) as a brief explan-
ation of the term the following; "Characters are said lo be
acquired when they are regularly found in those individuals
only who have been subjected to certain special and abnormal
conditions." I look the trouble lo expand ihis explanation of
the lerm at considerable b ngth. VVncther Sir Edward F'ry has
understood what was said, or not, is uncertain. Whether he
has, or has not, he proceeds to stale that this definilion excludes
the possibility of the inheritance ol acquired characters, and
renders the inquiry as to whether characters acquired in one
generation may be hamlcd on lo the next by inheritance
impossible ! And therefore, according lo Sir Edward, ihe
definition is a worthless one lor the present purpose. Sir
Edwaid's argument runs: " Characicrs can only be found
regularly either in individuals exposed to conditions which
induce them, or in individuals which have inherited them. If
then a character appears only in those individuals exposed lo
certain conditions, 11 does not appear in individua's by inherit-
ance." That is perfectly eoirect ; but where Sir Edward F"ry is
entirely wrong, is in his illogical assumption that the words
"does not appear by inhcriiance" are equivalent 10 "is not
transmissible by inheritance"; in fact, that "docs not" means
"never will or can." Surely when Sir Edward lakes pains to
Use such a lechnica.1 term as " identical proposition," he should
remember ihe difference between "particular" and "uni-
versal." Mr. Gallon's definition enables the observer lo recog-
nise and select for inquiry an acquired character, viz. one which
IS found in those individuals only which have been sutijected lo
ceriain special conditions — that is to say, one which is at a given
lime and place so found. Nothing is said or implied as 10
future posibilities. It is the purpose of the inquirer to ascer-
tain whether this acquired characier can appear in a later
generation as a transmitted character. In ihe specimens ex-
amined it has not yet so appeared. As Sir Edward justly
observe.'^, since it appears only in those individuals exposed 10
certain conditions, it does not appear in individuals l>y inherit-
ance. ■ but that has nothing 10 do with the question as lo
whether it ivill or can appear in individuals by inheritance.
.\ccotdingly ihe conclusion reached by Sir Edward Fry, that Mr.
Gallon's definition of the term "acquired characier " i educes the
proposition that acquired characters are not transmissible lo an
identical one, is erroneous, and due lo a confusion by Sir
Edward of a statemenl of what is observed at a particular
moment with a statement of what must be for all time.

It should be noted that Mr. Gallon's words do not furnish, or
profess to furnish, a definition by which any character may be
assigned to its class as either acquired or inheiited. It may

NO. 1315, VOL. 51]

240

NATURE

[January 10, 1S95

well be doubted whether such a definition can be framed in the
present state of knowledge. What Mr. Galton's definition or
|ihrase does accomplish, is to point out jt'OT,r characters which
may certainly be classtd as "acquired" and not "inherited,"
and from the study of which we may accordinjjly start in the
inquiry as to whether or not the acquired characters of one
generation may become inherited in a sub^equent generation.
"Characters," writes Mr. Gaiton, "are said to be acquired
when, &c." This by no means asserts that there are not other
characters which should be rej;ardcd as acquired, if we knew
fully about their history; for instance, at the very moment when
our observation is being made on a group of individuals, some
might conceivably be exhibiting a character inherited from the
last generation, and other specimens might be exhibiting exactly
the same character acquired de novo. Such cases (supposing
that they ever occur) would not help us at all m the attempt to
determine whether acquired characters are transmissible; and
the fact that they are not included in Mr. Gallon's definition
(though their existence is not expressly denied) renders that
definition a more practical one, and more useful to the experi
mental naturalist than a more comprehensive definition which
could not be brought to a practical issue.

Lastly, it seems to me that Mr. Gallon's definition is pre-
cisely what Lamarck pointed to in his " Premiere loi " and the
first sentence of his " IJeuxicme loi." The reciprocally
dcitruciive nature of the propositions contained in those
two laws I pointed out, in a former letter, and have not yet
had the pleasure of seeing, in reply, any defence of Lamarck's
position from one of his adherents. E. Ray LaNKESTER.

Oxford, January 4.

Boltzmann's Minimum Theorem,

The remarkable differences of opinion as to what the
Hlheorem is, and how it can be proved, show how necessary
is the discussion elicited by my letter on the oversight in Ur.
Wa'son's proof. Each of the four authorities who have replied
takes a different view.

Dr. Larmor enforces the view I put forward at the close of
my letter, and says that the theorem is what I said appeared an
ii /'riori po-sibility ; and I may here point out that his letter is a
complete answer to the argument I used in the Phil, Mag.
1890, p. 95, urging that, as there were as many configurations
which receded from the permanent state as approached it, there
was an u priori improbability that a permanent slate would
ever be reached. This argument was criticised at some length,
not really answered, in Messrs. Larmor and Bivan's Report
on Thermodynamics (British Association Report, 1891), but the
suggestive remarks there given helped me, I think, to arrive (inde-
pendently) at the complete answer given in Dr. Larmor's recent
letter. But my present use of the argument is not that which Dr.
Larmor criticises ; I now use it as a test of a particular proof
of the H-iheorem. I say that if that proof does not somewhere
or other introduce some assumption about averages, probability,
or irreversibility, it cannot be valid.

Mr. Burbury appears to consider that the theorem can only be
proved if we assume that some element of the distribution does
tend to an average (quite a different position from Dr. LarmorV),
and he is as yet unable to state the appropriate assumption
except for the case of hard elastic spherical particles colliding
or " encountering ' (for since a is constant in his last letter,
it seems as if the ./,... ,i„_^ cooidinales are really dummies).
Yet Mr. liurbury his already given what purports to be a
general proof of the theorem for any number of degrees of
freedom.

.Mr. Uryan thinks that a condition which excludes the reversed
motion is implied in Dr. Watson's proof, for he says that in
taking unaccented letters K/as proportional to the number of
molecules passing from one configuration to another in the
reversed motion, I make a less " natural "supposition than Dr.
Watson, who lakes accented letters ¥' /'. I cannot see what
virtue there is in putting accent* on or leaving them olT, and
after a very careful study of Mr. liryan's letter, I can only think
that he has fallen into some confusion owing to the way in
which he use* al one lime aarnltil and at another lime ttn-
(Uiented differential i, although (as he himself remarks) there is
no difference whatever between their accented and unaccented
prodiutt. Hut iven if .Mr. bryan be right, would he put us any
" forrarder "? What we want is a f-roof that the cdlisions will
make II decrease, and we can hardly be satisfied with a proof

NO. 1315, VOL. 51]

which depends on the previous assumption that the particles do
" naturally " tend to move in the desired way.

Dr. Watson meets my reversibility argument by saying that
H decreases even in the reversed motion, when the system is
confessedly receding from its permanent state. No other
corre-pondent agrees with him in this view, which would
indeed take a-Mij' all fhysiiol meaning from the H theorem,
for the decrease of II would then be quite unconnected with the
approach to a permanent slate. As to the other point. Dr.
Watson does not amend his proof himself, but says it is " easy '
to do, and so does .Mr. Hryan. Vet one has an instinctive dis-
trust of things which are said to be "easily seen,' and al all
events Dr. Watson's reference to the case in which the theorem
is aj<flied does not help one in the froof, ^Oiere it is necessary
to express separately the products of the differentials expressed
by the small and capital letters respectively in his "Kinetic
Theory. '

Mr. Burbury asks why I say ihe error law has been proved
for the case of hard spheres without the use of Boltzmann's
Minimum Theorem. I thought Tail had done so ( Trans. R. S. E.
18S6), and at all events I thought the ordinary investigation
showed that there was but one solution, that of the error law,
in that ca-e ; but perhaps I am mistaken.

Mr. Hryan says Lorenz gives the clearest account of the as-
sumptions in Boltzmann's theorem, lie would earn our gratitude
if he would slate them in his next letter.

Edw. p. Cui.verwell.

Trinity College, Dublin, December 29, 1894.

Aurora of November 23, 1894.

Observations of this aurora, by Mr. James T. Pope, at
Dingwall, in the north of .Scotland, have been sent to me by
Mr. II. Corder, of Bridgwater, a few particulars having also
been recorded here of the appearance, which, although the dis-
tance of this place from Dingwall falls but veiy little short of
400 miles, yet showed some very excellent agreements with
Mr. Pope's description.

Beginnings of the aurora were seen by Mr. Pope between 6
and 7 p.m., as a glow which brightened gradually along
the eastern, and sent up a few faint streamers from the western
parts of the horizon towards the north, until 6.30, gradu.ally
fading out, after that, till nearly 7 p.in. The glow then gradually
reappeared as a bright band, brighter in the east than in its
western half, stretched across the sky from east to west, some-
what southward from the zenith. This band of light continued
very bright for some time, but f.aded out gradually towards
7.30, the streamers in the north-west at the same time increasing
continually in brightness.

Near Slough the dispKay was first noticed about 7.15 p.m. as
a low ill-defined while bow, stretching, at about half the altitude
of those stars above the horizon, from under (," to under v Ur £b
Majoris (altitudes 19 and 24^ azimuths 13 W. and 16 E.)
from north). -V little later, towards 7.30 p.m., this arc had
become a bright narrow band, a degree or two in width, and
about 25° long, extending from j; Ursa; Majoris in the west
(altitude 15 , 19 W. of north) to a few degrees under 7 and 3
Ursa: Majoris (altitudes 16 and H) , 2' W. and 6 E. of north)
on a slightly downward slope lo some degrees eastward from
the latlerstar. It faded out partially about 7.30p.m., leavinglwo
bright remnants across 77, and under 3 Ursre M.ajoris, eaih about
8 long, while a third just similar wisp of light apiieared on the
same line's far Icl'tward prolongation ; this western offshoot of the
band continued with the other two short segments till all had
faded out at 7.45 or 7.50, marking the arc's considerable bul
not otherwise lraceablec<tension westwards, across «,C Ilerculis
(altitudes 17' and 15 , 60 and 55 W. from north).

Dingwall is about 390 miles distant from Slough, in Ihe
direction 18" or 19' west from north; so that it appears
that Ihe strong part of the glow-band sei-n most brightly in the
east from Dingwall, was alone observable here (if we except
the light-wisp in Hercules towards the west, at last), in the
vapoury sky near the horizon.

lirginning with an average altitude of between 9^" and xi",
or of about II , at 7.15, the band in growing stronger reached
an altitude, at Slough, of 14° or 15' towards 7.30, during
about the space of time when it was most distinct, and seen
most strongly in the east at Dingwall rxtending from east to
west somewhat southward from the zenith. If its altitude
there w.is at that lime about 60", and at Slough about 13°

January io, 1^95

NA TURE

247

above the south and north horizoos, respectively, of those places,
making the considerable correciions needed by the earth's
curvature in the 6° of latitude between them, the re-ulling
height of the luminous arch appears to have been about ninety-
five miles above a place about fifty miles south of Dingwall.
But the times of observation and the altitudes used being
only roughly assigned, and only somewhat vaguely comparable
together, an uncertainly of, it may be several miles, must no
doubt attach itself to this determination.

Two very slender and fugitive streamers only were seen at
Slough to rise from the horizon-glow before half-past seven.
But between about 7.35 and 7.40 p m. a dense tuft of
them, 8° or lo' wide, rose from a low, faint light-band then
visible at about half the altitude of the short arch-segment
across f, tj Ur>a; Majoris, crossing and enclosing that wisp
(^f light, to about half as high again as the wisp's altitude from
the horizon. This pillar of light grew faintly red before dis-
appearing, which it did in three or four minutes after springing
up, while the rest of the glow and the wisps (the one in
Hercules being the last one to be seen) also faded a.iay enirely
between 7.45 and 8 p.m. The distinct light-hand and the
tuft of reddish streamers were the only conspicuously bright
phases seen at Slough in the aurora of November 23, between
7.15 and 7.45 p.m., with the exception of the two very
faint and slender streamers which rose suddenly to a great
height across Ursa Majorat about 7.30 p.m.

The base of the pillar-like projection, resting on the faint
lower light-bow, was at about 8°, and its summit when highest
at about 24° above a part of the north-western horiz^ n between
S or 10°, and iS" or 20' west from north. Its western side
would ihu^ be just vertically over Dingwall, if the lower arch
which (ormed its base was at the same time in the zenith of the
latitude of Dingwall ; and this, it seems quite probable was
actually the case, from the following description of the closing
scene, liy Mr. Pope, of the aurora's progress after the main belt
of light had liroken up and dispersed itself, at about 7.30. lie
writes : *' At 7.30 p.m. the glow had almost disappeared, while
the streamers at this hour were most intensely bright, and ap-
peared ta radiate from a .>-mall and distinct part of the sky
situated in R.A. 358°, Decl. 43' north. Pievious to 7.30, no
streamers had been observed to radiate towards the south, but
between this time and 8 p.m. streamers were seen radiating
from the aforesaid part in all directions. After 8 p.m. the
display gradually faded out, and at 8. 30 very little trace of it
could be seen. The appearance at the apparent radiant point
when the display was at its height was most interesting ; appear-
ing sometimes as a solid mass of aurora, then suddenly breaking
up iuto fragments, and as-uming most curious forms, uniting
again, and so on. Not the slightest trace of the display was
visible at 10,30 p.m."

The altitudes of 8° and 24° observed at Slough, at the base
and top of the dense column of reddish streamers, nearly in
the direction (as described above) of Dingwall, must evidently
have related as direc'ly and definitely to this fine display of
radiation in the north of Scotland, ai the foregoing altitudes
at Slough of the bright band of light, before 7.30, seemed clearly
and obviously to supply good means for deteruiining approxi-
mately the hand's real height, by comparing them with Mr.
Pope's description of his view of the same band at Dingwall.

Making the same needed correcti-m, as before, for the diminu-
tion brought about upon the apparent altitudes observed at
Slough by the efTect of the earth's curvature, we may thuG
deduce a resulting real height of 75 miles above the earth's
surface, approximately, at the bases, and of 193 miles, ap-
proximately, ahove the earth for the summits of the streamers
which clustered over the neighbourhood of Dingwall, and pro-
duced the magnificent spectacle of the auroral corona in that
part of Scotland.

Should notes have been fortunately preserved at any other
towns in Scotland at considerable distances from, and especially
in lower northern latitudes than Dingwall, of the aspect, times
and bearings, or astronomical positions of this short but bright
aurora's rather peculiar features of development in its transient
display, much better conclusion; regarding the real positions
anil the extent and distribution of the spectacle might, without
doubt, be gathered from them, than those above roughly ex-
tracted from only very slight descriptions. But the roughly
reached results of the heights of the appearance may yet, for
the present, not be entirely worthless, on account of the
scarcely doubtful identities of the aurora's bright features, which

NO. I3I5. VOL. 51]

were recorded most dissimilarly in this rather surprising in-
stance, at two so very extraordinarily far separated places.

.\. S. Herschel.
Observatory House, Slough, December 24, 1894.

Peculiarities of Psychical Research.

On page 200 I see that Prof Karl Pearson suggests that it
would be a good exercise for some one with a stricily logical
mind and plenty of leisure to criticise '" the products oflhe chief
psychical reseaichers." May 1 say, as a member of the S. P. K.,
speaking for myself and fellow-workers, that we ask noihing
better than such a studious and searching criticism. One of
our main diflficulties is that our critics will not take the trouble
to study or even read our evidence, but are content to ridicule
what they conjecture to be our method;, and results from so
great an abitude of assured contempt, that we fail to recognise
ourselves in their travesty, and are therefore unable to derive
much benefit from their utterances.

Thus, for instance. Prof. Karl Pearson, before writing his
recent letters, has evidently not taken the trouble to refer even
to the abbreviated summary of certain card-drawing experi-
ments contained in Mr. Podmore's little book ; otherwise he
could hardly make the statements he does concerning the S. P. R.
record of them.

He objects to M. Richet's results as giving insufficient odds in
favour of telepathy, so that, as he says, it shows want of
acumen to adduce them. Would he then regard it as more
scientific to suppress them ? On the other hand, the enormous
odds against chance, shown in Mr. Gurney's trials, he also
says, on page 153, show a want of acumen (I don't know why,
but I expect because nothing could possibly exhibit anything
else on the part of an S. P. R. worker), and that such odds might
be otherwise accounted for. Does he then suppose that the odds
of, as he reckons them, tw'o thousand million to three are ac-
cepted by us as the odds in favour of telepathy ? Probably he
does, because there is at present no need to be fair to investi-
gators in an unorthodox field; but Mr. Podmore is careful to
slate the opposite, as follows (footnote to p. 27 of Mr. Pod-
more's little summary, in the Coiil/mporary Science Series, of the
evidence for Thou-.4ht transference so far as it exists at the
present time) : " Of course the statement in the text " [viz. that
" the probability for some cause other than chance deduced from
this result is '99999998"] "must not be taken as indicating
the belief of Mr. Edgeworth, or the writer, or anyone else, that
the above figures demonstrate thought-triinsference as the cause
oflhe results attained. The results may conceivably have been
due to some error of observation or of reporting. But the figures
are sufficient to prove, what is here claimed for them, that
.ttfWc' cause must l>e sought for the results other than chance."
And another qiolation may be permitted from Mr. Podmore's
pref-ice, which ought to silence irresponsible detractors like Mr.
H. G. Wells, and others, who seek to lead the world to suppose
that we have some cause at heart other than the simple ascer-
tain-uent of ihe truth, wha'ever it is, and that Mr. Podmore,
in particular, is a bigoted upholder of the certainty of telepathy.
This is the quotation: "The evidence, of which samples are
presented in the following pages, is as yet hardly adequate for
the establishment of telepathy as a fact in naiure, and leaves
much to be desired for the elucidation of the laws under which
it operates. Any contribution to the problem . . . will be
gladly received. ..."

Now, I observe that Prof. Karl Pearson has a contribution to
the problem, for in N.M'UKE of December 27, 1S94, p. 2C0, he
refers to certain experiments of his own, wherein by pure chance
he obtained results against whieh the theory of probalrility also
gave large odds. Would he be good enough to let us have these
results more precisely, as recorded at the time and signed by
winesses, so that they may furnish us with an example of the
methods of a "real scientific investigator".-' It will be very
unsatisfactory if we have no'hing but his memory to rely on for
the facts ; and as he well knows, it is necessary to have the
whole of a large number of trials before dcduc'.ions from the
theory of probability are legitimately applicable.

I observe, finally, that I'lof. Pearson, wiih plenty of good-
nature but some lack of originality, has refurbished Dr. Car-
penter's old joke about an "ortho-Crookes " and a " pseudo-
Crookes," and has directed it against me. I shall be well
content if he never manages to find a keener and more effective
weapon. Ot.iVER J. Lodge.

Liverpool, December 29, 1S94.

248

NA TURE

[January 10, 1895

THE STUDY OF CLOUD>

THIS monograph has been long and anxiously ex-
pected by all who take an intelligent interest in the
advance of meteorology, and recognise the long and

V\ '.. I. — Cvinui'.' r; ;t ■ i->.

profound study that the Rev. Clement Ley has made of
this subject. It is with great regret that we notice that
the preface is signed by a member of his family, and
that the zealous and energetic watcher of the clouds has
not been able to see his own work
through the press.

We have in this book to do em-
phatically with Mr. Ley's own obser-
vations, his own theories of cloud
structure, and his own nomenclature.
Although the author acknowledges in
the preface the valuable assistance
that he has received from the works
of other writers, it is curious to notice
how seldom in the text these authors
are referred to by name. One cannot
help feeling that it would have added
much to the interest and the instruc-
tive character of the book, if Mr. Ley
had systematically drawn attention to
the work of those who have laboured
with scarcely less industry than he
has in this department, if he had ex-
hibited the points of difference from,
and support given by, other observers,
such as .Abercromby, llildebrandsson,
Weilbach, and a host of other authori-
ties, who seem sometimes almost
ostentatiously ignored. It will be seen
that Mr. Ley does not offer anything,'
approaching a history of (he subject,
either on the theoretical or observa-
tional side. Opening with a prelimin-
ary chapter on the atmosphere and
the movements of vapour-laden air,
we have the general principles of cloud formation
explained. Although we have been accustomed to

1 "Cloudland: a Study on the Structure and Characters of CIoudK." Dy
Rev. W. Clement Ley, fl.ondnn : SLinlord, i^g* )

think that moisture condensed into cloud can only be
driven or rolled about in a limited number of ways,
and hence but few really distinct varieties of cloud
can be formed, our author subdivides the process of
cloud formation under several heads. The process which
he terms " interfret " seems very
nearly allied to the Luftwogen of
Helmholtz, though there is no mention
of this authority in the text. Mr. Ley
states that when approximately hori-
zontal currents of air dilTering in velo-
city and direction move over one
another, an intermingling of the par-
ticles will result, accompanied by
whirls, ripples, and waves, varying in
size and shape according to the
velocity and direction of the current.
This effect he attributes to friction,
and this seems to be the chief differ-
ence between him and the German
physicist, who sees a more complex
problem in the mixing of two fluids
of different specific gravities. If the
colder current is uppermost, the re-
sulting action is called " interfret '' ;
if the warm moist current is above,
then "reversed interfret." To clouds
formed by the descent of moist par-
ticles through warmer and denser air,
the term " inclination '' is applied,
and the final nomenclature adopted
rests on subdivisions of these classes
uf formations.

An adequate nomenclature of clouds
has long been, and we think it may
be said, is still, a desideratum. Luke Howard's
terms still survive, and after nearly a century's
use cannot, and will not, be entirely superseded.
Stratus, cumulus, and cirrus have too strong a hold on

Fig. 2.— Cumulo-nimbus (same cloud a^ in l-ig. 1 1.

the vocabulary to be dislodged, and however much they
may be subdivided, they must remain the basis of classi-
fication. Mr. Ley therefore retains these terms, but an
eye educated by some fifty years of constant study, has

N<

1315. VOL. 51 I

I

JANUARY lO, 1895]

NATURE

249

seen and learnt to recognise many varieties of shape and
form, arising possibly from real ditierences of structure,
which require distinctive appellations, and make the
description somewhat cumbrous. To quote the entire
list of subdivisions would occupy no small space. Leaving
out of the question fog, which is itself divided into three
classes, we have the clouds of interfret, inversion, and
inclination, each subdivided into five different varieties.
To this list, large as it is, must be added several ad-
ditional subdivisions, all presenting marks of dissimi-
larity, and it is suggested, typical of special states of
weather in different portions of the globe. Each of the^e
classes is described at considerable length, and many of
them are admirably illustrated, both by coloured plates
and photographs. We have recently reproduced
(Nature, vol. xlix. p. 342) some admirable specimens of
rloud photography, due to S. Manucci of the Vatican
Observatory, illustrative of the distinctive characteristics
of cloud formation. Mr. Arthur Clayden has secured
some very admirable specimens, worthy to be classed
with those of the Italian artist. We give in Figs. I and
2 the reproduction of the same cloud (cumulo-nimbus)
after an interval of ten minutes, in
which the shifting character of clouds
is well illustrated. The truthfulness
to nature is shown very conspicuously
in an evening picture of the same
variety of cloud (Fig. 3).

But the important question is, will
illustrations, however carefully exe-
cuted, give to persons of ordinary
intelligence that insight into cloud
structure which enormous experience
has given to Mr. Ley, and enable
them to discriminate with facility and
certainty between the various classes ?
The author raises the objection, not
as existing in his own mind, but as
having been suggested to him by
others whose opinion he values, that
the classification here presented is
too complex. We would respectfully
associate ourselves with those who
have suggested this doubt. Mr. Ley's
contention is, that greater simplicity
of description might induce a larger
number of observers to contribute
something, but that the luiliic of the
whole mass of such observations would
be of small amount, through however
long a space of time they were con-
tinued. The main value consists in
the evidence it affords of the different forces at work in
the air, and its consequent trustworthiness as a weather
guide, and on this point there will be many different
opinions. The same description of cloud does not pro-
gnosticate the same weather in all countries, or at all
times in the same country. The method and cause of
development are as important as the character of the
cloud itself. Cumulus may sometimes be the promise of
a fine day, or prove the precursor of a shower. A man
who "forecasts'' by the clouds alone, is in the same
position as a man who relies on the indications of a
wheel barometer. He simply considers one variable in
a very complex result. But Air. Ley looks forward to a
time when every man shall be his own "weather pro-
phet," and when every individual and institution may
be provided with weather telegrams and the means of
correct and intelligent interpretation. In the multitude
of counsellors so created there may be wisdom ; there
will certainly be confusion.

Waiting tor this consummation, it seems most desir-
able that the same kind of cloud should be called by the
same name by all observers ; and simply having regard to

NO. 1315, VOL 51]

the main divisions, it will be admitted on all hands that
this amount of progress has not yet been effected. We
have then to consider whether this book, valuable as it
is, will promote this end, and we are afraid that it will
prove an edged-tool to beginners. To the advanced
student it can easily be understood that this work is most
welcome, but there still seems necessary a simpler system
to serve as an introduction for the tyro. Mr. Ley may
very well say that he addresses himself only to skilled
observers, and to some this will be a sufficient defence,
but this skill is not easily acquired, and we look
for a graduated system, along which a student may
advance confidently and scientifically. Abercromby and
Hildebrandsson recognise and would recommend a classi-
fication of ten divisions, a system of which we believe
the author disapproves. Captain Wilson Barker would, if
we understand his arrangement correctly, still further
simplify this system, and therefore it does not seem im-
possible to lead the student along an easy incline in
which he would gradually accumulate experience, rather
than plunge him at once into the subtleties and pitfalls
which Mr. Ley prepares for the beginner.

Fig.

-Cutnulo-niTnbus (evenini^).

It is easy to understand how difficult a problem was
submitted to the International Meteorological Committee
when they were asked to adopt and sanction a uniform
nomenclature of clouds, and how prudent they were in
declining the invitation (N.\'lURi:, vol. xxxviii. p. 491).'
Simply having legard to the fact, that meteorologists are
generally agreed that the same cloud forms and cloud
structure are to be met with all over the world, it would
seem that an International Congress was admirably
adapted for the settlement of such a scheme. But it was
felt, and the feeling will be still more general after the
perusal of Mr. Ley's book, that our knowledge of the
physical and structural process of cloud formation is in
a progressive state, and therefore final classification im-
possible. Mr. Ley would probably be the last to con-
sider that his book possesses the element of finality. He
has not only learnt and taught much, but he has also
learnt, better than most of us, how much more there
is to learn.

W. E. P.

1 This subject is slill cngiRing the attention of .in International Congress
(Seep. 185.)

2. so

NATURE

[January io, 1895

SIR CHARLES NEWTOX, K'.C.B.

THE hand of death has lately fallen heavily on the
ranks of the older scholars ; and classical archae-
olog>' has especial losses to record Only a few months
back, there passed away Heinrich Brunn, the lioyen a.n&
most picturesque representative of German Hellenism ;
and we in England have now sustained a loss no less ]
severe. Though Newton had of late years become too
infirm for active work, and had in fact done little since
his retirement in 1SS5, it is now, when he has gone from
among us, that his loss will be most keenly felt. It was '
not so much in his actual achievements, though these
were considerable enough, that his truest claim upon our
recollection lay ; nor yet in the f.^ct that he had practi-
cally opened up a new science for English scholarship :
it was more than all in the personality and force of
character of the man, which impressed itself on all with
whom he came in contact, and the masterful influence
which was by no means confined within the limits of his
own science. It was to this that he owed his success ;
and there have been few instances in which a necessity
has been so opportunely met by the man most adapted
for it. For when Newton joined the Museum in 1S40,
the study of actual monuments was still in its infancy ;
Greece itself was very little known, and a pseudo-clas-
sicism had been evolved from the mistaken illustration
of literary sources with an often inferior Gricco-Roman
art. Behind him lay the period of learned and in-
genious but useless theory ; two things were needed to
clear away this tangle of ide^is — a fuller supply of the
best practical material, and a wider scientific method.

At that time the Departments of Antiquities at the
Museum, which now are four, were all united in one.
The disadvantages which such an arrangement must
have entailed are obvious enough, but there was
this compensating advantage, that a young man in
Newton's position was at the outset enabled to attain a
certain familiarity with the wider aspects of his study,
and perhaps a breadth of view and sympathy which is
more difficult at present. He was thus by his training,
as well as by his natural bent, led to a large view of
things.

In an address to the Arch;cological Institute at Oxford,
in 1850, he urges a powerful plea for the comparative
method in archaeology and, as the necessary corollary,
for enlargement of museums. In this address, which as
archxological teaching was singularly in advance of its
times, the writer has laid down the formula; upon which
the modern science of archaeology may be said to take
its stand. A museum must not be a mere collection of
disjointed, disconnected phenomena, but the central con-
sulting-room, as it were, to which all scientific questions
may be referred for comparison and elucidation. Classical
art and archaeology, like all other studies, cannot but
lack perspective in isolation : the external conditions,
the ethnographical characteristics, the position of the
Hellenic race in its relation to the rest of mankind, their
art, architecture, life, and thought must be collated and
classified with a due regard to the continuity and correla-
tion of things. The arch.xologist, in short, " must travel,
excavate, collect, arrange, delineate, decipher, transcribe,
before he can place his whole subject before his mind.
But the plodding drudgery which gathers together his
materials must not blunt the critical acuteness required
for their classification and interpretation : nor should that
habitual suspicion which must ever attend the scrutiny
and precede the warranty of archrcological evidence give
too sceptical a bias to his mind.'' The key-notes here
sounded were kept steadily in mind throughout his
whole life. It was but a few years after, that his sojourn
in the East, as consul at Mytilene, enabled him to put his
ideas into practice, and to initiate for ICngland the "era
■of the spade."

NO. 131 5, VOL. ",1]

The discovery with which Newton's name will always
be inseparably associated is that of the Mausoleum at
Budrum, collections from which now fill almost an entire
room at the British Museum. Budrum had been visited
by Prof Donaldson early in the century, and the pre-
sentation to the Museum, in 1S46, of the twelve slabs
removed from the castle of the Knights of St. John, had
called renewed attention to this monument. In 1847
Newton published a memoir, in which Donaldson's site
was selected as that which probably concealed the
ruins — a conjecture which other travellers contemptu-
ously rejected. It was not till 1857 that Newton was
enabled to verify his conjecture by actual digging, and
the account which he gave of his discovery, in his
"Travels and Discoveries in the Levant" (p. 86), is one
of the most fascinating episodes in a fascinating book.
Even when the site was thus determined beyond all
doubt, the difi'iculties had only begun ; the obstacles of
Turkish officialism and native greed were enough to have
broken the heart of a less indomitable energy ; but his
own untiring efforts, backed by the friendly assistance of
Lord Stratford de Redcliffe at Constantinople, brought
the undertaking to a well-merited success.

Lord Stratford was only one out of many friends
whom Newton succeeded in enlisting in the cause he
had at heart ; he had pre-eminently the priceless faculty
of inspiring others with his own enthusiasm ; possessed
of considerable social gifts, he was enabled to make
many friendships, which served him in good stead both
at home and abroad. If a special grant were required,
whether for excavating a promising site, or for enriching
the Museum with an important collection, he rarely failed
to wring a reluctant consent from a Treasury too apt to
neglect any cause which is not sufficiently self-assertive.
During most of the period of his keepership he was thus
able to maintain or to encourage enterprise or explora-
tion abroad, set on foot by men who had caught the in-
fection of his energy in personal contact with himself
Smith and Porcher at Cyrene, Dennis at Benghazi,
Pullan at Prienc, Salzmann and Biliotti at Budrum and
Rhodes, Wood at Ephesus, and, more recently, Ramsay
in Asia Minor, all owed the initiation of their enter-
prise, or very material support, to Newton at home.
Perhaps one of his most solid claims to our
gratitude lies in the fact that he was thus instru-
mental in obtaining no less a sum than / 100,000
in special grants for the purchase of collections for the
British Museum, over and above the annual sums voted
by Parliament. Of these the most important was pro-
bably the great Blacas collection in 1867, a transaction
which is admirably illustrative of Newton's resourceful
self-reliance and power. The French Government (and
probably others also) were known to beinclined to treat for
the collection, and the English representative had at short
notice to determine a sum which should be at once
enough to carry the position, and yet not be deemed ex-
travagant. Newton telegraphed on the Friday to Panizzi ;
next day the trustees of t!ic .Museum met, DisracU came
purposely to the meeting, and the historic treasure was
ours. .

To his energetic guidance the Hellenic Society and
the British School at Athens both owe in a large degree
their initiation and their present position. It was indeed
in such practical initiation, and in the inspiration of
others rather than in actu.al teaching, that Newton's true
sphere lay. Vet all who know his writings, and still more
those who had the privilege of personal intercourse with
him, will acknowledge the debt they owe to his teaching,
either direct or indirect. To any one regarding the period
over which his activity extended, from a lime when
archsological science was, as it were, casting its skin,
down to the complete transformation of to-day, to any
one who knows the masses of now useless literature which
form the cast-off slough, it is really astonishing to turn

January io, 1895]

NA TURE

SSI

to Newton's " Essays on Art and Archaeology," and to see
how fresh and how living the opinions expressed even
more than forty years ago still remain. Though cautious
sagacity and a conservative temperament were his pre-
vailing characteristics, yet when the occasion needed he
could speak with no uncertam voice ; it is a remarkable
fact, for instance, that his article on the epoch-making
discoveries of Schliemann, written at a time when the
altitude of scientific men was still undetermined or op-
posed, remains to-day, so far as it goes, an admirable
exposition of the subject. His attitude on such subjects
was specially characteristic of his favourite study —Greek
epigraphy — for which a man needs a wide range com-
bined With a patient methodical accuracy. He might,
indeed, have said of himself, with his great contemporary,
Brunn, "In a critical discussion I would rather err
methodically than hit upon the truth without method":
a golden watchword ior this age of hurry and competition.

NOTES.

Tkof. RiCHTHOFEN has been elected a Correspondent in
the .Section de Mincralogie of the Paris Academy of Sciences.

Dr. d'Arsonval has been appointed to the Chair of
Medicine in the College de France, in succession to the late
Prof. Brown-Sequard.

The death is announced of Dr. Josef Schioter, Professor of
Bacteriology in Breslau University, and distinguished for several
important researches in the domain of botany. Among the
deaths of other foreign scientific men are : M. Stieltjes, the
eminent Professor of Pure Mathematics in the Toulouse Univer-
sity ; Dr. C. Studiali, Professor of Physiology in the University
of Pisa, and Dr. J. G. Brinton, at Philadelphia. Dr. Brinton
was known for his botanical works.

Prof. Blake has been appointed by the Government of
Baroda to the temporary Directorship of the newly-built Slate
Museum at Baroda, and sails this week for India.

Mr. J. E. DUERDEN, Demonstrator of Biology at the Royal
College of Science, Dublin, has been elected Curator of the
Institute of Jamaica.

The Paris correspondent of the Lancet reports that arrange-
ments have been made at the Pasteur Institute for the immediate
despatch of tubes of anli-toxic serum to any part of Trance.
It will thus be seen that M. Roux and his assistants have not
been idle. Indeed, both the Institute authorities and the
public have worked with a will ; the latter having, through the
Figaro, and by means of gifts made directly to the Institute
contributed up to December 31, 1894, no less a sum than
61 1,000 francs {£2\.^\o). This does not include 100,000 francs
1^4000) just voted by the Chambers, and which will doubtless
become an annual subsidy. The Institute now possesses, for
immunising purposes, a stud of 136 horses, a total that will
probably be ultimately increased to the maximum of 150. O:'
these, tweniy are kept by the Municipal Council of Paris at a
cost of 20,000 francs (£'600) a year, for the benefit of the
Paris hospitals and poor. At Villeneuve-d'Ktang— a property
ceded by the State to .VI. Pasteur in 1886— there are seventy-
nine horses cared f.-r by a capable veterinary surgeon and
his staff. That the animals flourish under the r.'gii/u of
good feeding and periodical bleedings adopted, is proved by
the presence in good health at Alfort of a sturdy Brittauy pony
which has hitherto supplied no less than 420 litres of blood.

There will be a special technical meeting of the Royal
Geographical Socety, in the Map Room of the Society, on Tues-
day, January 22, at 4 p m., when Prof. .\. W. Rii.ker, F R S.,
will read a paper on " Terrestrial Magnetism."

.*\N Austrian polar expedition is being organised by Herr
Julius von Payer, with the view of securing the artistic repre-

NO. 1315, VOL. 51]

sentalion of the physical features of the east coast of Greenland.
The actual work will begin in latitude 74', and will extend
beyond latitude 77°. It i-; anticipated that the expedition will
be ready to start in June 1896.

The weather has continued very disturbed over the British
Islands during the past week ; northerly gales have occurred
with considerable frequency on our northern and western
coasts, but ihe conditions have been quieter than of laie over
the southern portion of the kingdom. Heavy snow has fallen
in Scotland, causing serious interruptions to the railway and
telegraphic services ; snow has also fallen in many other parts
of the country. Sharp frosts have occurred in the Midland
districts, as well as in the north and east ; and on Tuesday the
thermometer in the screen registered 19" at Wick, while ten
degrees of frost occurred in several parts of the United
Kingdom.

The study of the "ejected blocks" from a volcano is a
peculiarly interesting one, for by the careful piecing together
of evidence much may be learnt of the internal processes which
accompany the outward and visible eruptions. This study has
been undertaken by Prof. Johnston-Lavis for Monte Somma,
and some recently published papers contain a portion of the
results at which he has arrived ( TransacUons Edinburgh Geol.
Soc. vi. 314). Of the many varieties of stratified rocks that
have been torn off from the walls of the volcanic chimney by
the rising lava, those of Tertiary age show the least metamor-
phism ; while in the deeper-derived Cretaceous limestones all
stages of metamorphism are to be found. The earliest changes
appear to be ihe carbonisation of any organic matter to form
graphite, and the recrystallisation of the calcite in larger grains.
Then as interchange of constituents takes place between the lime-
stone and the metamorphosing lava, various lime-silicates appear
in a fairly definite order, until finally we have formed that great
variety of minerals for which .Monte Somma has long been
famous. The occurrence of pcricUa (MgO) is of interest in
view of the abundance of hydrochloric acid among the gases
emanating from Vesuvius, for that mineral is artificially prepaied
by healing magnesia in hydrochloric acid gas. Many of the
minerals formed under these condidons of metamorphism lead
to decompose rapidly under more normal conditions, and
associations of serpentine, tremolite, brucite, &c., are formed,
such as are well known in areas of regional metauaorphisai.

The analogy between these Vesuvian blocks and certain
Archxan rock-masses is carried to a striking extent in a further
paper, in the authorship of which Dr. J. W. Gregory joins with
Prof Johnston-Lavis {Trans. Roy. Dublin Soc, vol. v.
ser. ii. No. vii.). Here many specimens are described
which show in the most complete manner the association of
characters that led to the belief in the organic nature of the
Canadian Eozoon. The authors consequently suggest that the
Eozoonal structure in its typical localities was developed in the
limestones by the contact metamorphism of the associated
crystalline rocks— a view which, they point out, is in harmony
with the conclusions arrived at by Prof. Lawson on purely
straligraphical considerations. The disproof of the organic
nature of Eozoon may therefore be considered complete.

The disease of Anbury, or Finger and Toe, is met with where-
ever the turnip crop is cultivated, but it is probably nowhere
more destructive than in the north of England. An experiment
bearing on the disease, briefly described in the Journal of ihe
Royal .\gricultural Society, by I'rof. W. Somerville, will there-
fore interest all agriculturists. The experimenter emphasises
the fact that the disease is extremely infectious, and may be
easily induced by inoculating a soil perfectly sound with soil
from a diseased field. Such diseased soil, however, may be
easily disinfecled by lime, .-i fact which points to the patho-

2s2

NA TURE

[January io, 1895

logical phenomena being due to an organisoi — presumably
PUsmodiothora brassic.i. This being so, too great care cannot
be taken to prevent soil or diseased roots being conveyed from
a field which is diseased to another which is sound.

A SociEvr which has a total of more than eleven thousand
governors and members, may fairly be said to be in a flourishing
condition. Such is the Royal .Agricultural Society ; and with so
great a membership, it is no wonder that a large amount of im-
portant work is carried on under its auspices. The current
quarterly yi>Kr«a/ of the Society has among its contents special
articles on the rotation of crops, light railways, and the trials of
oil engines at Cambridge. It also contains the annual reports
of the consulting chemist, Dr. J. A. Voelcker ; the consulting
botanist, Mr. \V. Carruthers, F. R.S. ; and the zoologist, Mr.
Cecil Warburton. The report of the Council shows that in
the Department of Comparative Pathology and Bacteriology,
established at the Royal Veterinary College by the aid of a grant
from the Society, the work in the research laboratory has in-
cluded investigations on tuberculosis, diphtheria, anthrax, and
other diseases, and the use of mallein and tuberculin for the
detection of glanders and tubercle in the earliest stage. The
further experiments which have been made, have materially
strengthened the evidence in favour of both agents as aids to
diagnosis in d jubiful cases of disease. We note that the Council
hive elected as an honorary member of the Society, Prof. \V.
Fleischmann, Director of the Agriculiural Institute of the Royal
University of Kunigsberg, in recognition of his distinguished
services to European agriculture. The annual country meeting
of the Society will beheld this year at Darlington; Leicester
has been chosen as the place of meeting for next year.

Every naturalist is acquainted with the elaborate springlike
mechanism by which the woodpeckers and humming-birds are
enabled to protrude their tongues with such rapidity for the
cipture of insect prey. These remarkable instances of adapta-
tion have been more than once described, and some other
special modifications of the avian tongue and its bony supports
will be recalled by ornithologists. In a recent number of Der
Zoologiiilie Garten (Frankfurt, xxxv., November, 1894), llerr
Schenkling-Previ't redescribes these cases after a renewed in-
vestigation, and also supplies a quantity of interesting informa-
tion on the form of the tongue and hyoid apparatus of birds in
general. The old idea that the woodpecker transfixes its prey
with its sharp-tipped tongue is probably not yet extinct, but
Herr Prcvut adds his opposition to this opinion, and states that
the insects are agglutinated to its tongue by the .--ticky secretion
with which its surface is copiously covered. Although the
foim of the tongue usually corresponds to the shape of the bill,
there are exceptions to this rule, as, for example, in the waders,
kingfisher, and hoopoe, which, in spite of their long bills, only
possess small caitilaginous tongues ; in the pelican, indeed,
the tongue is altogether rudimentary. In most birds, whose
food consists of .--eeds, the tongue is dart- or awl-shap;d ; in
others, spatulate ; rarely, vcrmilorm or tubular. In some birds,
such as the owl, which swallow their prey entire, the tongue is
broad and serves as a mere shovel. In the hedge-sparrow,
nuthatch, woodcock, and others the tongue is bifid or irifid at
its apex, while in the humming-birds the tongue is split into
two branches almo>t to its base, and is used for actually
gripping the small insects on which these resplendent little
cieatures subsist. In a family of parrots (Trichoglossida:) the
tongue is provided at it' apex with a brush of some 250-300
hair-like processes. In the parrots, the tongue is thick and
fleshy, devoid of horny barbs or papilLx', and is even suspected
to possess sense-organs of taste. Herr Priv.pt concludes his
concise but interesting paper with some remarks on the influence
of the form of tongue in birds on their varying powers of
NO. I3I5. VOI-. 51]

articulation. It is interesting to note that the parrots, the form
of whose tongues most closely resembles that of man, are able
to imitate his language more nearly than any other birds.

The first number of the Botanisches Centralblalt gives, from
the annual report of the Socieic des touristes du Dauphinc, an
account of the various attempts to establi>h .A.lpine botanic
gardens in the Jura, Tirol, Siyria, the Bavarian .\lps, Switzer-
land, &c.

The number of Bonnier s Rrjtie GenJrale de Botani^iie for
December 15, 1S94, contains a biographical sketch of the late
Prof. Duchartre, with an enu neration of his contributions to
physiological, morphological, and systematic botany, amount-
ing to 240 papers or separate publications.

The first part is published of x.'he/ahrbucher fiir wissenschajt-
liche Botanik under the new editor-hip of Prof. Pfeffer and
Prof. Strasburger. It contains the following papers: — "In-
vestigations on Bacteria," by Dr. A. Fischer, and " Physio-
logical investigations on the formation of callus in cuttings of
woody plants," by Herr H. Titlmann.

Lord Lilkokd's "Coloured Figures of British Birds" have
now reached their twenty-ninth number, and contain a series of
excellently-drawn chromo-lithOjjraphs of our native species.
Four or five more parts are required to finish the work, which,
when arranged, will fill ten or twelve crown-octavo volumes.

The veteran naturalist, Dr. R. A. Philippi, of Santiago,has
just issued an illustrated memoir, in quarto, on the stags of the
.\ndes, which will form part of the ".Vunals of the National
Museum of Chili." Besides the two ordinarily recognised species
of the sub-geims Furcijer — Cerz'us chiUnsii and C. antisinsis —
Dr. Philippi describes a third specie^, Ccrvus hrathyceros, from
Northern Peru, which appears to be well established.

The birds of Bulgaria and the adjacent provinces of Turkey
have, hitherto, been little invC'itigatfd by European orni-
thologists, and are consequently imperfectly known. .\ good
contribution to our knoArtedge of this subject has just been
made by the publication o( Reiser's " Ornis Balkanica." The
author is Custos of the Museum at Sarajevo, in Bosnia, and
has travelled extensively in the Bulgarian provinces.

The 119'h number of the Biolo^ia Cenlrali Americana of
Messrs. Godman and SiUin, which has recently been issued,
contains coniinuaiions of the "Birds" by Messrs. Salvin
and Godman, of the Coleoptera by Dr. D. Sharp and Mr.
Champion, of the Ilymenoptera by Mr. Cameron, and of the
"Butterflies ' by Messrs. Godman and Salvin, all illustrated
by coloured plates of the highest exoellence. Various other
subjects are in progress, and there can be no diubt that the
work, when complete, will give us an account of the zoology
of an important region of the New World, executed in a style
and with a completeness which has hardly ever been approached
by any similar undertaking.

An important paper on tropical fodder grasses appears in the
Keiv Bulletin for November. The object of the paper is " to
draw attention to a fe<v grasses that have attained to first rank
for fodder purposes in the tropics, and to give particulars re-
specting the conditions under which they have been found to
thrive." The information given will be of considerable assist-
ance in indicating grasses suitable for cultivation in tropical
countries. It will also show some countries that, while they
have been spending time and money in endeavouring to intro-
duce foreign grasses, they have overlooked excellent indigenous
grasses close at hand.

Messrs. Blackie and Son have published a small book
entitled " First Stage Mathematics." The contents are limited
to the rcijuirements of the Code of the Education Department
for mathematics as a specific subject.

January io, 1895J

NA rURE

253

The publication of Mr. Hutchinson's " Archives of
Surgery," which has lapsed for six months, is now being
resumed. No. 21 will appear in a few days, with additional
letterpress as well as nine plates, and this number, which com-
fliences vol. vi., will contain a chronology of medicine from
the fifteenth to the nineteenth century. The publishers will in
future be Messrs. West, Newman, and Co.

A ROUGH list (No. 147) of rare and valuable books for sale,
has been issued by Mr. Bernard Quaritch. The list includes
a number of important archaeological works, and a few works
belonging to the natural sciences. Mr. W. F. Clay has also
just issued a list of scientific books, including the works on
chemistry lately purchased by him from the library of the late
Prince Lucien Buonaparte.

We have received a copy of El Obrero, a fortnightly papei
published at Quito, Ecuador, with a summary of meteorological
observations made at the astronomical observatory at that
place for the month of September. Observations in that
locality are very desirable, and we are glad to see that their
publication is to be continued, and copies to be distributed to a
number of places.

The Meteorological Office of Argentina has ji'st issued
vol. ix. of its Anales in two large quarto parts, forming a
splendid contribution to the climatology of that part of the
globe. The first part, which contains 678 pages, gives the
observations and the means deduced from them, for Cordova,
during the years 1872-1892 ; while the second part, which ex-
tends to 400 pa^^es, contains an exhaustive discussion of the
data, and of the influence of the various elements on each other,
t.g. of wind on temperature, &c. It is not possible to give in
a brief space any summary of so comprehensive a work. W^e
merely note that the monthly mean temperature varies between
73° in January and 50' in June. The rainfall varies considerably ;
the mean of a number of years gives about 26 inches. The
Director of the .Service is G. G. Davis, who is also a member of
the International Meteorological Committee, and attended the
meeting at Upsala in August last.

Science Gossip is now one of the brightest and most diversi-
fied monthlies for the lover of science. The January number is
remarkably good. Mr. J. T. Carrington, one of the editors,
contributes a number of replies he has received to a letter ask-
ing for an opinion upon the use of the word "scientist." The
word is never allowed knowingly to appear in contributions
toNATURE. .'V twin-elliptic pendulum, exhibited by Mr. Joseph
Gould at the Royal Society's soirees last year, is described by
the inventor, and seven exceedingly fine figures, drawn by means
of the apparatus, are reproduced. There is also a summary of
Schiaparelli's views about Mars ; and a page of astronomical
■ephenierides and notes, as well as scientific news, and notes on
various branches of natural science. We are glad to see that
•physical science comes in for a fair share of attention, but there
is still room for improvement.

Six volumes have lately been added to the comprehensive
series of reprints, " Ostwald's Klassiker der Exakten Wissen-
schaften," published by Engelmann, of Leipzig. No. 54 con-
tains J. H. Lambert's paper, published in 1772, on the projec-
tion of terrestrial and celestial maps. The fidlowing number is
also on map projection, and is made up of memoirs by Lagrange
;i779) and Gauss (1822). Translations of two papers by Sir
Charles Blagden, from the Philosophical Transactions for 1788,
appear in No. 56. The subject is the effect of various substances
in lowering the freezing point of water. Treatises on thermometry
lind a place in No. 57, which includes five of Fahrenheit's
papers, three of Reaumur's, and a paper by Celsius. The
volume thus comprises all the important communications con-

nected with the foundation of the three thermometric scales.
The classical work of Scheele on the nature of air and of fire is
reprinted in No. 58 of the series ; and No. 59 contains Otto von
Guericke's experiments with Magdeburg hemispheres, carried
out in 1672. The quaint illustrations of the original paper give
this volume additional interest.

The additions to the Zoological Society's Gardens during the
past week include a Black-eared Marmoset (HapaU penicillala)
from South-east Brazil, presented by the Lord Auckland ; a
Pardine Genet (Gmetta pardina), a Two-spotted Paradoxure
INauJinia binotata) from West .Africa, presented by Lieut.
F. E. W. Batt ; a Sparrow Hawk [Accipiler nisiis), British,
presented by Mr. A. .M. Lees Milne ; two Long-nosed Croco-
diles (Crocodihis cataphraclcs) from West Africa, presented
by Captain F. W. Raisin ; a Robben Island Snake (Coronella
phocarum) from South Africa, presented by Mr. G. R. Picton
Thwaites ; two Grey Parrots \Psillacus erilhactis) from West
Africa, deposited.

Erratum.— la NATURE of December 13, 1894, p. 157,
column two, line one, for "of a" read "near the." The
cascade represented in the note serves to show clearly the
overhanging ledge of limestone.

OUR ASTRONOMICAL COLUMN.

The Greater Nebula of Orion. — The numerous photo-
graphs that have been taken by means of portrait lenses during
the past few years, go to show that many of the so-called
celestial spaces are really filled with filmy nebulosities. Dr.
Roberts's classical photograph greatly extended the limits of the
old Theta nebula in Oiion, but few astronomers would care to
say that it represents the great " tumultous cloud " in its
entirety. Indeed, three photographs obtained by Prof. W. H.
Pickering in 1889, with a portrait lens, revealed a large zone of
nebulosity surrounding the belt and sword handle, and extend-
ing towards y Orionis. The significance of these photographs
has perhaps been somewhat overlooked, but attention is again
directed to them by a paper communicated by Prof. E. E.
Barnard to Astronotny and Astro-Physics for December. By
means of a lens only li inches in diameter and 3! inches focus,
Prof. Barnard has recently taken two photographs of the Orion
constellation t (or the lens takes in nearly the whole constella-
tion at one view), with exposures of two hours and one hour
fifteen minutes respectively. These pictures show "an enor-
mous curved nebulosity encircling the belt and the great nebula,
and covering a large portion of the body of the giant." With-
out doubt, the nebulous stream which has left its impression
upon Prof. Barnard's photographs, is the same as that of which
the existence was recorded by Prof. Pickering. The "Great
Nebula" in Orion is therrfore but a pigmy compared with the
greater nebula thus revealed. It is not too much to believe
that in a few years the immense band of nebulosity will be
shown to be more or less filled with luminous haze, the old
nebula being probably but the brightest part of a nebula
involving the whole constellation.

The Transit of Mercury. — We have already noted
observations of the transit of Mercury on November 10, 1894,
made in Europe and America. News has now reached us of suc-
cessful observations, made under the direction of Mr. J. P.
Thomson, at Mr. F. D. G. Stanley's Observatory, Brisbane. The
instrument employed was a 6 inch equatorial byGrubb, stopped
down to four inches. Times of contact at egress were carefully
taken. When the planet had come sufficiently above the
horizon to be observable, it had advanced about two-thirds
across the solar surface. The whole periphery of Mercury was
remarkably clear and well-defined. There w.as no trace of haze
or vapourous aureola around the disc of the planet, but a bright
spot was distinctly seen near the centre. \\ the instant of in-
ternal contact at egress there was a faint phenomenon resembling
ligament. This, however, was only momentary. When the
external contact occurred, the planet's limb tangential with that
of the sun was remarkably clear and sharp. There was not a
trace of disturbance, and the phase was regarded as a pure

NO. I^I

J'D-

■•OL. 51]

^54

NATURE

[January io, 1S95

geometrical contact. No trace of the planet's periphery could
be seen when it left the solar disc, alihough it was carefully
looked for.

The Government .\slronomerat Sydney, Mr. II. C. Russell,
states that fifteen photographs were taken of the transit of
Mercury. He reports that as the planet crossed the sun it
presented the appearance of a round anl intensely black disc
without any fringe such as has been noticed in former transits,
and owing to the unsteady state of the air towards the close of
contact, the "black drop" phenomenon took place, preventing
clear definition.

.\N Important .\steroid. — The minor planet BE 1894
proves to be a very important member of the community to
which it belongs. M. Tisserand remarks, in Complts reitiius
for December 26, that, of all the asteroids, it has the smallest
perihelion distance, leaving out of count Brucia Pi»), of which
the elements arc very uncertain. When HE is at its descend-
ing node, its distance from the orbit of the earth is only 067
the radius of this orbit. On account of this circumstance, the
asteroid is most favourably situated for the determination of the
solar parallax. The elements given by M. Tisserand are as
follows : —

1894 November 47 Paris Mean Time.

m ... 23 18 38-5

»■ - 357 25 535 )

ft ... 212 36 51-4 > Mean Eq. 1894.

I ... 23 s 57 I

<(> ... 18 4 81

li ... I002"I5I

log ii ... 0366049

Prof. Adams' Collecti:d Mkmoirs. — .\ note in the
Obserualory informs us that I'rof. K. A. .Sampson, formerly
Isaac Newton Student at Cimbridge, is gradually reducing to
order the la ge quan'ity of MS.S. left by Prof, .\dams. The
memoirs relating to lunarlheory have been completely separated
and arranged, and the lectures on Jupiter's sat'-llites are also
well advanced. Memoirs on the solution of the infinite de-
terminant, and others on some small matters, have been
separated from incidental and preparatory work; but a consider-
able quantity of matter is si ill outstanding, so it may be one or
two years more before the examination can be completed, and
the collected works be ready for publication.

THE BIRD-WINGED BUTTERFLIES OF THE
EAST.

T N the days of Curtis and Stephens, the late Mr. \V. C.
■*• Ilewitson was a diligent collector and observer of British
insects of all orders, and likewise an ornithologist, who pub-
lished several editions of a well-known work on British biids'
eggs. But the day came when he was to discover, as he
says in one of his own publications, that a butteifly might be
beautiful, though it was not a British species ; and he became
ihnroughly infatuated with these beautiful thing":, lo the study
and illustration of which he devoted the remainder of his life.
And this is how it came about, as he used to relate to those
who had the privilege of the acquaintance of a kind old en-
thusiast, who5c work was of immense value to the progress of
entomology in its day, though he was unable to sympathise
with or to appreciate the vast revolution in nioHcrn biology
which many men with whom he was intimate and men, too,
not much younger than himself, with Darwin, Wallace, and
Bates at their head— succeeded in effecting in a comparatively
short time.

<Jne Hay of the days, a« it says in the " Thousand and One
Night.s," he happened to be at Stevens's Auction Room«, when
a lot was put op containing lievcral species of the well-known
\^tna% .liiilfi/ia, lliibncr, ot I/elerochioa, Boisduval, as it was
then called, which replaces our Kuropean While Admirals in
.South America. The butterflies attracted his attention, for at that
time it was a novelty lo him lo see a nuinbcr of butterflies so
clohly resembling each other, and yet quite distinct ; and he
bought the lot. lie turned round, and saw Prof. WeslwooH,
who said to him, " What, are you buying Imtternie-i ?" "Ye*,
I am," he answered ; and ihiis he commenced the formation of
hit great collection of butterflies, now in the British .Museum,
which was fed by the cream of the expeditions of Wallace and

NO. 13-5, VOL. 51]

Bates, and remained unrivalled up to the day of his death, in
1S78, though there are now several collections in England,
France, and Germany which surpass it.

The exact dale when this epoch-making event in the
history of the study of butterflies occurred, we do not know.
It is true that the first paper published by Ilewitson
on exotic butterflies related to the genus Hclerochroa, and
was published in the Anna's aiiJ Magazine of Naluiaf
History in 1S47 ; but in the previous year, Edward Doubleday
had commenced his great work on the " Genera of Diurnal
Lepidoptera," the letterpress of which was c impleted after his
death by Westwood ; and Ilewitson executed all the plates, as
joint author. It is. therefore, probable that Ilewitson had
already commenced the formation of his collection before that
time, especially as his own great work on exotic butterflies was
commenced before the actual completion of the " Genera."

Yet, since the death of Ilewitson, new countries have been
opened up, and wonderful butterflies have reached Europe,
never dreamed of by Ilewitson, or which remained unattainable
objects of his desire, to the last. Chief among these may be
mentioned the butterfl es of Central .\sia, a terra incopiila
except for Kversmann's and Nordmann's papers, in Ilewitson's
time ; and the butterflies of the Eastern .Archipelago, (or the older
naturalists, and even Wallace and Lorquin, much as they were
able to accomplish, only succeeded in sampling some few
islands, and many others now known to produce some of
the strangest and grandest butterflies in existence, remained
unvisited and unexplored.

Ctiief among the butterflies of these islands .ire the grand
species to which Hois luval applied the generic name of Orni-
thoptera, or bird-winged butterflies, of which only a few, and
those not the most remarkable, are found on the mainland of
India, the Malay Peninsula, and .Suuih China. Many of the
species are very closely allied, but others are so diflVrent that
they can hardly be regarded as congeneric ; and it will be wall
to discuss them by groups.

First of all, we may divide them into the black and yellow
species, and those with black and green, orange, or blue males ;
and each of these two main groups includes a variety of species,
which are hardly all congeneric.

Two species only, 0. Priamus and 0. Helena, were known
to Linne. Several more were figured and described before
the end of the last century ; but only eight species were de-
scribed as late as 1836, and thiiugh several others were after-
wards described, Ilewitson's collect!' n only included eighteen,
counting several forms which he treated as varieties. Now,
however, Mr. Rippon's large work, " IconesOrnilhopterorum,"
at present in course of pulilication, is intended to extend to
eighty folio plates. Hut there is always some difliculty in
determining the exact number of species, for these butterflies
are variable, and in the numerous islands of the East there are
a great number of closely allied local race;, and we are hardly
in a position at present to determine whether it is best lo treat
them all as distinct species, or as different formsof two or three,
and (specially is this the case with the group of Ornilhoptera
Priamus.

It will be best lo commence with the black and yellow
species, which are found on the Asiatic Continent, and the
Mal.ay Islands, and therefore in nearer and more acessible
localities than any of the green species, except 0. Brookcana.
They are also found in the .Molucca^, tVc, but less numerously,
being more abundant in the Malay Islands.

Of this group, Oriiillio/>tera Pompcns, (_'ramer, from Java,
may be regarded as typical. The males of this and the allied
species are of a velvety black, with the ncrvures more or less
bordered with grey, and the spaces between the ends of the
veins on the hind margin, bordered with white. The hind
wings are of a beaulilul golden yellow, intersected with the
black veins, and bordererl with black along the hind and inner
margins. The inner margin forms a fold which conceals the
brown scent-bearing scales, and is fringed with long hairs.* On
the inner margin, the black border projects into the wing in a
series of long cones between the nervures. The females are
similar, but the grey markings of the fore wings are more
extcndeil, and on the hind wings the scent organs are wanting,
and there i^ a row of black spots opposite the cones of the
Irordcr, which are often connected into a continuous series, as

I Scr, for A fuller detcription of llic scent -oreani in i^rntlhoflern^ Haasc^
" Corrcspondcniblatl dcscntomologischcn Vcrcinn, Iris lu Dresden," I. pp.
93-94-

January lo, 1895]

NA TURE

255

well as with the cones themselves. The fore wings are long and
narrow, measuring about five or six inches from tip to tip, and
the hind margin is very oblique. The hind wings are rounded
and dentated, but form almo-t a right angle at the anal angle of
the hind wings. Behind the head, we often find a red collar in
one or both sexes. We have not thought it necessary to figure a
species of this group, representatives of which may be seen in
almost every collection of butterflies from India and the adjacent
islands ; but we have given figures of the larva and pupa of
O. pomptus (Fig-:. I, 2) The transformations of all the species
of Ornithoftera are very similar, as far as they are at present
known ; the larvae are rather short and thick, with rows of long
fle-hy spines, and with the retractile scent-producing and defen-
sive bifid horn on the head, common to all the true Papilionida.
In the yellow group, these larvae are generally brown, with a
bro.id pale oblique band about the middle.

The amount of yellow on the hind wings of the butterflies of
the Pompeus group differs very much. Sometimes we find
only a narrow black border, sometimes a very broad one, and
sometimes the base is also black, the yellow colouring being re-
stricted to a broad band, or even to a large spot in the centre.
Two or three yellow species, found in Malacca, Borneo, &c., of

V^7 '-' .

'm H '& '^"- '^'^

Flc. I. — Larva of Oi-ytithoptera PomJ>ctts, Craw.

Fig. 2. — ^Mf^oi Oi'nithapUra Pompeus, Craw.

-which 0. Amphrysus, Cramer, is the commonest, are distin-
guished fiom the others by having radiating yellow instead of
grey lines on the fore wings of the males. Occasionally speci-
mens of the yellow group are met with, wiih the yellow replaced
by deep golden red; but it is not certainly known whether this
peculiarity is accidental or specific.

The grandest of all the yellow species, however, is 0. Ma-
gellamts, Felder, a native of the Philippine Islands. If the
butterfly is held towards the light, there is nothing to dis-
tinguish it from any other yellow OrntthopUra ; but if you turn
your back to the light, and hold the drawer on a level with
your eye, you will see a marvellous iridescence of the most deli-
cate pale silvery blue and green glancing over the whole of the
hind wings of the insect. There is nothing to compare with it
in any other butterfly, not even in Morpho Sulkoivskyi : the
nearest approach to it is in the iridescence over the ted spots in
some South American Papilios (which, though much smaller,
are considered to be closely related to Ornilhoptera), and in the
iridescence over the yellow on the wini;s of some Smth Ameri-
can butterflies belonging to the genus Eiistlasia, Hu'mer. But
these latter belong to a different family (Lemoniidtc), and are
small butterflies, not exceeding an inch and a half in expanse,
-whereas 0. Magellaniis is a grand black and golden-yellow

butterfly, measuring six inches across the fore wings. It is
closely allied to several common Indian species, though none
of these show more than the very faintest traces of iridescence.
But in order lo obtain the full effect, it is necessary that O.
Alagellanus should be se\ Jlal. If the wings are set sloping,
according to the old English method, now bem.j rapidly super-
seded by the flat setting which has always been in use on the
continent, the effect of the iridescence is almost entirely lost.
0. Magellanus is still a scarce insect in c dlections.

Amcjng the more abnormally coloured species of this group
we may mention O. Plaleni, Staudinger, from the Island of
Palawan, in which the male has t .vo broad golden-yellow blotches
on the centre of the hind wings, separated by the upper branch
of the subcostal nervure ; on the underside, and in the female,
this colour fills up a large part of the centre of the hind wings.
A still more remarkable species was lately discovered by Mr.
Doherty in the Island of Salibobo, or Lirung, one of the
Talautse Inlands, and was described and figured by Mr. Rippon
under the name of O Dihcrtyi. The male is of an intense
silky black above, with a slight greenish glow in certain lights ;
on the underside is a yellow ban I, parallel to the hind margin,
and cea>ing before the inner margin. The female has brown
fore wings, with the usual grey markings inclining to reddish ;
the hind wings are darker, with a small irregular buff patch in
the centre, divided by the nervures ; on the underside this
paich is larger, and the ends of the nervures are bordered with
the same colour. These butterflies measure about six inches
across the wings.

Next to the golden yellow group of Ornithoplera, we may
place the splendid O. Hippolylus, Cramer, the female of which
sometimes measures nearly eight inches across the wings.

It is not very closely allied to any other species. The fore
wings resemble those of the last group, but the hind wings in
the male are dark smoky brown, with a row of large yellow
spots extending all round the wings, except on the side next
the body ; these are bordered, both outside and inside, by a row
of neatly connected large black spits. In the female the yellow
markings are more extended, and the base of the wings is
black ; the lower part is bluish-grey ; and over the yellow and
grey part of the wing runs a marginal row of large white spots.
The fold on the hintl wings is filled with long flaffy white hair.
This insect is met with in .\ nboina, and Piepers, the Dutch
entomologist, records his having seen a specimen mobbed and
driven away by small butterflies, just as small birds will mob
and drive away a hawk in Europe.

Mr. Kippon has proposed the name Pompeoplera for the
foregoing series of species ; but the types of Ornithoplera are
Papilio Priamiis and Helena of Linne, and as the former is
fixed as the type of Irohies, HUbner, by Iliibner's inclusion of
it in the second volume of his "Sammlung exotischer
Schnietteilinge," Helena remains as the true type of the genus
OrniV/w/Zfra, as coriectly given by Mr. Moore in bis " Lepi-
doptera of Ceylon," though Dr. Scudder, having overl.joked
both this point and the impropriety of regarding Helena as the
type of Trollies, specifies Priamiis as the type of Ornilhoptcru,
and Helena as the type of Troides.

Next to the golden-yellow species of Ornithoplera, we come
to the green, blue, and orange section, to which the name of
Trollies should, as « e have just seen, be applied, and of which
Papilic Priamiis, Linne, from Amboina and Ceram, is the
type. To 0. Priamus and its allies Mr. Rippon restricts the
name of Ornithoplera.

The species of TroiJes are all very similar except in size
and colour, and we have copied Mr. Rippon's figures of
the smallest species, T. Riihmondia, from Australia (Figs. 3,
4, i \ '■ 'R- S- * '■ This insect varies in size from 4.5 to
nearly 6 inches in expanse, the female being always the largest :
but in most of the other species in the group, the wings expand
6. 7, or even 8 inches in seme of the females. The males of
this section have velvety black fore wings, with a wide
green bar parallel to the costa, and another, more or less ex-
tended, at the hinder angle of the wing, running along the
inner margin towards the base, and curving upwaids along the
hind margin. The hind wings are green, with a row of black
spots (sometimes reduced to one or two) along the hind margin.
There is a long brown patch of raised scales towards the hind
margin of the fore wings in the male, which is quite absent in
the yellow group (Ornithoplera, true). The females are brown
butterflies, with two irregular rows of while spots on the fote
wings, the innermost very large (though obsolete in some

NO.

VOL.

•■iO

2S6

NATURE

[January lo, 1695

species), and with the hind wings pale beyond the middle,
and crossed by a row of black spots ; the pale part of the wing
is whitish within them, and brownish, or yellow, beyond. The
sides of the thorax are generally bright scarlet under the wings,
and the abdomen is generally yellow in the males, .and brown
in the females. These green species are not found in the Malay
islands, but throughout all the Moluccan and Papuan islands,
as far as Au'itralia : though many of the most remarkable are
very restricted in their range, being confined to one or two small
islands.

Sometimes, as in the male of T. arrtiana, Felder, a narrow
green stripe runs along the median nervure and its branches, in
the male. In certain lights the green of the fore wings exhibits
very remarkable changes of colour to yellow, coppery-red, or
blue ; the copper-red is mo5t conspicuous in T. Pegasus,
Felder, from New Guinea, and the blue in T. Eumaiis, Rippon,
from the .\ru Islands.

FiCS. 3. i. — Troititi KichnwmiiaimaAt, two varieties).

T. Eumaus leads nson to T. Urvillianus, Gucrin-Mcni'ville,
from New Ireland, from whence several specimens were ob-
tained during the voyages of the Coi/iiille and the Astrolabe
between 1820 and i8jo; but no more were brought to Kuropc
for fifty year«. They were named after the famous French
Admiral, Dumont d'Urville, a worthy successor of our own
(Japlain Cook ; and who subsequently perished, with his wife
.md orly son. in the great accident on the Versailles Railway,
r>n May 8, 1842, one of the most terrible and fatal of all on
record.

In the male of T. Urvillianus, all the portions of the wings
which arc green in other >pecie'i, are of a deep blue ; hut with
an iridescence or opalescence in various lights, showing green or
coppery. T. Urvillianw has lately been found in New Guinea,
New Ireland, Duke of Vork Island, and the .Solomon Islands.
The bntlcrny doe< not a|>pcar to I'C difficult to capture, as Mr.
Gervaie F. Malhcw, K.N., frequently found them descend to

NO. 1315, VOL. 5 l]

low bushes; and he also obtained the larva, which is black,
with carmine tentacles, and fleshy spines, the latter tipped with
black ; about the middle of the body is an oblique white stripe.
It feeds on a species of -Xristolochia, sometimes quite close to
the ground.

From T. Urvillianus, we may pass on to other remarkable
species. One is T. Crasus, Wallace, from the island of
Batchian in the Moluccis. Here the green or blue of the species
we have already mentioned is repKaced by a brilliant golden
orange, shading into green in certain lights. Mr. Rippon treats
T. Craius and Urvillianus as a separate see/ion {/'riim^'plera)
of Ornithoplera (which name he retains for the /V-wwK.f-group) ;
but they can hardly be considered sufficiently distinct from the
others to rank as a separate ^cwwr, as he himself admits.

.\fter T. Crasus we may place T. LyJius, FcUler, which re-
places that species in the island of Gilolo or Ilalmaheira, one of
the Northern Moluccas, not far frooi Hatchi.an. Here the sub-
costal band on the wings of the male is of a very deep coppery-
red ; but both in this species and in T. Crasus, the only other
mark on the fore wings, except a short dash at the base of the
inner margin, is the very large oval brown sexual blotch. The
hind wings are of a rather paler colour than the band of the
fore wings, and varied with yellow. The female of /". Crasus
does not differ much from the ordinary females of the I'riamus-
group, but that of T. Lydius is black, with the cell, and two

K11,. J.— ;■ ',..:. V ii uftntoftiiia (feiiKile).

complete rows of long spots, concave at the extremity, and Ihe
inner row vc-ry large, between the nervures beyond the cell.
The hind wings are of a yellowish-brown, with the base,
nervures, a suhmarginal row of mostly connected spots, ami
another on the hind maigin. black.

From the genus Truidis, we pass on loamther splendid grouji,
.'Eth'oftera (Rippon), in which the male has apparently no
masses of raised scent-producing scales on the wings, and the
hind wings are verv long. Intermediate between Troides Crasus
tmiK .Elheoplera Vidori.,-, the type of .AV/;j-.'//<;a, stands .-E. (?)
Tilhonus (De Ilaan), from New Guinea, a buttciHy which
remained unique in the Lcyden Museum fur fifty years. The
fore wings of the male, which are seven inches in expanse, are
black, with three changing green and yellow bands, two united
at the base, the first running narrowly along ihe subcislal
nervure, and much widened before reaching Ihe apex of the
wing ; the second, broader at the base, extending along the
lower part of the cell, and growing bro.ider beyond as it curves
towards the hind margin ; Ihe third runs along the inner margin,
nearly to the hinder angle of the wing. The hind wings arc
varied with green and golden-yellow, and are narrowly bordered
with black. There are three black spots on the hind wings on
the upper side, and more beneath, as well as on the hinder part
of the fore wings ; the abdomen is yellow, with some black
spots above on the sides, towards the extremity.

January io, 1895]

NATURE

257

The female is not certainly known, for it is doubtful whether
the insect which has been regarded as such may not be that of
another species.

Ailhcoptcra Victoyiit (Gray), the type of its genus, is likewise
a species of which liide was known for many years. A
sinj^Ie female, damaged by shot, was brought back by Mac-
gillivray from the voyage of the HeraLl, and remained unique
in the collection of the British Museum for more than thirty
years, when several specimens were obtained by Mr. C. M. Wood-
ford in the Solomon Islands. The true yF.. Vicloria proves to
come from the island of Guadalcanar, and themale measures six
inches across the fore wings, which are long, narrow, and rather
pointed. It is black, with a wide green and yellow space for
■ inelhird of the distance from the base, and another blotch of
the same colour near the costa before the apex, divided by the
veins. The hind wings are very concave at the anal angle, and
are green, bordered outside by a yellow band, on which .stand
three orange spots (also visible below, where they have black
spots between and beyond them), and beyond this is a narrow

Fig. 6. — SchoEtihergia Paradisca, Staudtnger (m.ile).

black border. The female is a black butterfly, with much
broader wings, seven inches in expanse. There is a row of
large white spots, and another of submarginal spots on all the
wings ; on the fore wings a yellow band, while at the extremity,
runs along the cell, and another along the inner margin ; on the
costa of the hind wings is a yellow band. The larva is dark
brown, with long carmine fleshy spines; the retractile fork is
yellow.

In the island of Malayla is found the closely-allied 0. Rts;iinr,
.Salvin, a larger insect, the male of which has more black on the
hind wings, and three orange spots surrounded with green on
the orange part of the w ing, instead of the yellow band.

These butterflies, as well as Tioiiics Uni/liaiiiin, frequent the
sweet-smelling white flowers of Cerhcra Oiiollmn, a plant allied
to the Oleander, which is common throughout the ICast Indies
and Polynesia.

The next genus, Schociibergia, Pagensfecher, is in some re-
spects the most remarkable of all, as it is the only one allied to

Ornilhaplera which is tailed. The only species, S. Paradisia,
Staudinger, was captured by natives in the Finisierre Mountains
in New Guinea, at a height of 500 metres. The male (Fig. 6)
measures five inches acro-^s the tore wings, which are black, with
two broad green bands glossed with golden yellow, cne below
the costa, and the other between the cell and the submedian
nervure, and curved upwards, opposite the hinder angle of the
wing, to beyond the middle of the hind margin. The hind
wings are remarkably short, not more than three-fifths of the
length of the inner margin of the fore wings, but they are very
long and narrow, with the hind margin almost straight, and a
tail quite as long as the wing is broad, at the outer angle ; the
inner margin is lobate The hind wings are green, more suf-
fused u ith orange-yellow than the fore wing>, and narrowly
bordered outside with black, but with the base and inner
margin very broadly black.

Ttie females are larger, and exhibit nothing unusual in form
or colouring, being black, with two more or less developed
rows of while spots on the fore wings, large towards the costa,
and diminishing towards the hinder angle, where they converge ;
on the hind wings is a pale submarginal band, extending over
the lower half of the wing, but much narrowed towards the
co*:ta ; the outer part is yellow, shading within to bluish-grey
and whitish ; across it runs a row of black spots.

Fig. 7. — Trogonoptera Hrcokeana^ Wallace (male).

This is the only known species of the group with tails on
the hind wings ; but this seems to be a tendency in some Papuan
Lepidoptera. Thus the true Atlas Moths belonging to the East
Indian and South .\merican genus Allactis, Linne, are all tail-
less ; but there is a closely-allied genus [Cosei/iocna, Putler)
found in New Ireland and at Cape Yori,-, which has very long
tails ; in fact, these moths are probably the largest tailed
L/pidoplera known.

We have one more Eastern genus to mention, which we have
left till last because it occupies a rather isolated position, and
would have interrupted the sequence of our genera. This is
Trogonopte: a, Rippon, the type of which is T. Brookeana,
Wallace, which was discovered in .Sarawak, Borneo, by Dr.
A. R. Wallace, and named after Kajih Brooke (Kig. 7). It is
the only green Ornitlwptcra which inhabits the mainlanil of Asia
(the Malay Peninsula) and the adjacent islands of .Sumatra and
Borneo. It measures from six to eight inches .across the wings,
which are black, the fore wings very long, with the hind margin
very oblique, and the hind wings short, rounded, and dentaled.
The front of the thorax and the sides below the wings are
ciimson. The fore wings have a row of large green submarginal
triangles, with the pointed ends resting on tfie hind margin,
and each triangle intersected by a nervure ; on the hind wings
the whole centre is green. In the female, the green is much
more glossed with brassy, and is bordered wiihin with blue,

NO. I315. VOL. 51]

2^8

NATURE

[January io, 1895

which is rarely the caie in the male, and the green markings,
which disappear towaids the cosia in the male, are there in
the female replaced by long bifid grey streaks between the
nervures. An interesting account of the habits of this species,
as noliced by various observers, is given by Mr. Rippon in his
" Icones Otlhopierotum."

One other species of this genus is known : T. Trofana, Stau-
dinger, from Palawan, an island about a hundred miles Irom the |
north coast of Borneo. Here the brassy-green spois of the fore
wings of the male are shorter and more subconical, instead of |
forming long isosceles triangles, and there is only a row of
coonec eJ green spots across the hind wings, bordered within
with blue ; the base of the wings is also marked with rich
blue across the nervures, and along the edge of the fold of the
hind wings. |

Some idea of the market value of conspicuous insects, before
they are sent over in numbers, may be gathered from the circum-
stance that a specimen of this butterfly recently sold for ;£^IS at
Stevens's auction roims. |

This is the last genus included in Ornithoptera which is met |
with in the East, but the two largest West African butterflies
are likewise considered to belong to this group, and may re- \
ccive a passing notice here. One of these is the famous Drurya
Aitlimj.hus, which was brought by Smeathman from Sierra |
l.eone, and figured by Drury in 17S2, and, afterwards, by ^
Donovan in his " Naturalists' Repository," but of which no
second specimen wa> seen in Europe till 1864. It is an insect
with very long and narrow wings, from seven to nearly nine
inches in expanse, and much resembles some gigantic species of
the very characteristic African genus Air,ca. It is black, with j
large tawny spots and markings toward- the ba<e of the fore
winjjs, the greater part of the hind wings is tawny, with a row
of black suhmarginal spots. It has been suggested that this
insect possibly mimics an extinct Acriza, for the largest known
species of that genus are not much more than half the size of
/). Antimacktis. The female is considerably smiller than the
male {a raiher unusual character in butterflies), and has much
shorter wings. There are two specimens in the Hewitson Col-
lection in the British Mu>eum, and ii was one of these that Mr.
Hewiison used to say cost him /500. The real explanation is
probably that he spent that amount in sending out agents to
collect butterflies in Africa, with special instructions to look for
D. Antiinachus. Of late years, many specimens have been
brought to Europe, and the butterfly can now be bought at a
comparatively reasonable price.

The other West African butterfly now recognised as belonging
to the Otnilhoplcra group, but lor which a new genus will pro-
bably be created before long, was described by Hewitson under
the name of rapilio Zalmoxis. It measures about seven inches
across the wings, which are broader and more rounded than in
the typical Eastern buiietflies of this group. The male is o( a
raiher pale blue, with black borders, slightly spotted with blue
on the hind wings, and with black mart;inal lines between the
nervures, and a black cosIa rn the fore wings. The male
is fairly common in collections, but the female, which is of a
dull yellowish grey instead of blue, is si ill very rare.

It is curious that, like the gorilla and chimpanzee, the nearest
relatives of these two great West' African butterflies (if we except
Papilio Kidltyanus, White, a West African bulierfly which has
some resemblance \oD. Antimachtis, though it is much smaller
and redder), are to be looked for in the islands of the Eastern
Archipelago. W. F. Kirby.

A aWew element in the nitrogen

CROUP.
A NEW element appears to have been discovered by Dr.
■^ Bayer in the residual liquors derived from the older pro-
cess for the extraction of aluminium from red bauxile, and an
account of it is commnn cited to the current issue of the
HulUltn ill la Social,' Chiinii]ue. The liquors in question con-
sist chirfly of »ulphaic and carbonate of sodium, but there are
also present considerable quantities of chromic and vanadic
acids, and smaller quantities of molybHic, silicic, arsenic,
phosphoric, and t.ingsiic acids, lOKcthcr »iih alumina, magnesia,
a'd lime, and an acid of the new clement. In order to isolate
the latter, the vanadium and chromium arc first removed, ihc
former as the difficultly soluble ammonium van.vlate, and the
lat er as hydrated sesquioxide. The filtered liquid is then
saturated with sulphuretted hydrogen, and the sulphides, all of

NO. 1315, VOL. 51]

which are soluble in the alkaline liquid, are precipitated by
hydrochloric acid. This precipitate exhibits a deep brown
colour, due to the new element. When dried it pre-
sents a brown earthy appearance, and burns readily with
evolution of sulphur dioxide and formation of a bright
brown powder. Concentrated nitric acid instantly causes
ignition, and formation of a deep brown solution, from
which a small quantity of a yellow precipitate of a compound of
molybdic and arsenic acids is deposited. The brown liquid con-
tains no tin, antim iny, or tellurium, but sill retains traces of
vanadium, molybdenum, and selenium. These elements arc
best removed by calcination of the sulphides immedi.itely after
their precipitation wiih hydrochloric acid when selenium is
volatilised, trentment of the residue with ammonia and
ammonium nitrate, which precipitate tlie last traces of
vanadium as ammonium vanadate, and concentration of the
filtered liquid which causes deposition of ammonium molybdate.
During the concentration two distinct crops of diflerent crystals
are obtained, the first and most sparingly soluble being cubic
crystals of an olive-brown colour, and the second the much
more soluble ammonium molybdate. The olive-brown cubic
crys'als contain the new element, together with a little
molybdenium. The latter is readily removed by dissolving the
crystals in dilute hydrochloric acid, and passing a current of
sulphuretted hydrogen through the liquid heated to about 70°.
The new element is not precipitated by sulphuretted hydrogen
in an acid solution. The filtered liquid is then allowed to
evaporate in the air. At first it is bluish-violet in
colour, and contains the new element in a low
state of oxidation; subsequently it becomes oxidised, and
the colour changes to lemon yellow. The oxide in the
latter stage possesses marked acid proclivities, and probably
corresponds to the formula R^Oj. The acid itself is soluble in
water, fiom which it is deposited in yellow crystals, which at a
red heat fuse to a brownish yellow mass. Ammonia trans-
forms the acid into a crystalline powder of olive colour,
presumably an ammonium salt, which readily dissolves in hot
water and crystallises from the solution in cubes nn co iling.
I The solution is olive green and is piccipitated by strong
ammonia. The solution of the acid after reduction wllh
I sulphuretted hydrogen in presence of hydrochloric acid yields
with ammonia a voluminous deep violet-brown precipitate,
which rapidly becomes crystalline. The precipitation is not
complete, hence the supernatant liquid is colouied violet.
Caustic soda and sodium carbonate likewise incompletely pre-
cipitate it, owing to solubility ol the precipitate in excess of the
reagent with formation of a soluble salt. Chlorides of barium
and calcium produce greyish-violet precipitates of the salts ol
those metals.

An especially in'eresting reaction is that with ammonium
sulphide, with which the highly oxidised yellow solulion
of the acid yields a deep cherry- red colouration, due to a sulfo
salt. Acids piecipiiate from this solution a sulphide of the
colour of iron rust. Silver nitrate produces a green precipitate
of the silver salt, soluble both in nitric acid and in ammonia,
and if the solution in the latter solvent is effected at a moderately
elevated temperature the silver salt is deposited in crystals upon
cooling. Magnesia mixture gives after standing a lew minutes
a green precipitate analogous to ammonium mngnesium
phosphate, and owing to the slowness of the iirecipiiaiion the
latter occurs in the form of relatively large crystals ; moreover,
the prccipit.ation is complete after a short time, for the lupiid
which at first is green becomes colourless. A y.-llow precipitate
is likewise aflf^orded with a nitric acid solution of ammonium
molybdate, .as in the case of phosphoric aclil. The chlorides of
the new element appear to be volatile, for very considerable loss
occurs on attempting to remove by ignition any admixed
ammonium salts, (or instance from the solution obtained after
removal of the vanadium as previously described. A yellow
sublimate is produced having all the characters of a chloride of
the new element, and which is readily soluble in water.

A suflicient quantity of the new element In the form of any
of its compounds has not yet been accumulated to enable exact
quaniiiative analyses to be carried out, but Dr. li.aycr hopes
shortly to have obtained the amount rcqul-itc for this purpose
and (or the dc'ciminalion of the atomic weight of the element.
There appears to be htlle room for doubt that it will prove to
be one of the missing elements iircdlded by I'lof. MendeleeflT
in the nitrogen-phosphorus group. Ii exhibits characteristic
spectroscopic lines in the green, blue, and violet.

A. E. TUTTON.

January lo, 1895]

NA TURE

A'

SCIENCE IN THE MAGAZINES.

FULLY illustrated description of Mr. Maxim's experiments
in aerial navigation is contributed to the Century by Mr.
.Maxim himself. The account of the new flying machine and its
various parts is the best we have seen. The total result of Mr.
.Maxim's experiments is now fairly well known. It has been
proved that a machine, carrying its own engine, fuel, and pas
sengers, can be made poweilul and light enough lo lift itelf in
the air. The experiments also prove that an aeroplane will lift
a great deal more than a balloon of the same weight, and that
it may be driven through the air at a very high velocity, and
with an expenditure of power very much less than that required
to drive a balloon at even a moderate pace. In addition to this,
they have clearly shown that a well-made screw propeller ob-
tains sufficient grip on the air to propel a machine at almost any
speed, and that ihe greater the speed the higher the efl'iciency
of the screw. These results have certainly forwarded the
problem of aerial navigation. The Ccidiiry also contains an
article on customs, fetes, and celebrations in .-Xmerican Colleges
for Women ; and, in the same magazine, a brief description is
given of the new anti-toxin treatment of diphtheria.

In the Natioitul, Mr. Stanley Lane- Poole pays tribute to the
memory of the late Sir Charles Newton. (A notice of some of
the researches of this distinguished archxologist will be found
on p. 250.) Prof. Koxwell replies, on behalf of professed econo-
mists, to Lord Farrer's article in the October number of the
same review, upon the Standard of Value. Towards the end of
a contribution on the present state of the Royal Navy, Mr. VV.
Laird Clowes expresses himself upon the sul>ject of the education
of naval olTicers. Referring lo the training of a naval ofBcer,
he remarks : " A century ago ... it was not necessary that
he should know anything of chemistry, of engineering, of
h)draulics, of pneumatics, of electriciiy, and of half a dozen
other subjects concerning which he must now know more than
a little. . . . But at present, if an officer goes to sea, he has to
suspend, in a great measure, iheprogress of his education. Theory
is at the base of nearly all of it, and the theory is just as re-
quisite as the practical experience, and, indeed, in some matters,
even more so. . . . The seaman is in process of becoming the
engineer ; eveiy year he becomes more and more the engineer ;
and I am certain that a much briefer experience of .he sea than
was formerly needed is now required towards the formation of
a good officer. Per contra, he who would be a good officer
requires very many things which aie more easily obiainable at
I'ortsmoulh than in mi l-.\tlantic. We may regret the change,
but we must not shut our eyes to ficts. And I think the sooner
ihe change is fully recognised, and the whole scheme of the
education of naval officers is radically altered, the better will it
l)e for the service." Mr. Clo*es, however, does not seem to
have sufficiently taken into account the difference between the
duties of the navigating officers of the navy, and Ihe engineers.
Naval engineers at the present time receive admirable training
in boih the theory and the ptaciice of the machinery with which
a modern battleship is equipped. Does Mr. Clowes h'dd that
navigating ofTicers should receive the same kind of training?
The statement that the seaman is in process of becoming the
engineer, will hardly be accepted lilerally by those acquainted
with the naval service. The engineers and engine-room arli-
liceis are fast becoming the most important men on board, but
the distinction between ihem and the navigating staff is as
liard and fast as ever it was.

In the Niw Kericw are some verses having a singularly strange
and appropriate rhythm, by the late R. L. Stevenson, in which
he has expressed his keen sense of the struggle for existence ;
and we find in the criiical article upon this Inst among the
many losses of 1894, by Mr. Archer, how profoundly modern
scientific thought had affected his philosophy. There is also
the first instalment of an eccentric story iiy Mr. II. G. Wells,
in which, after certain rather paradoxical dealings with the four
dimensions, a "Time Traveller" staits into futurity upon a
Time Machine. What he found there remains to be told in a
subsequent number, but there certainly seems scope for the
scientific imagination in such a siory.

A paper on "Feeling of ISeauty in Animals," in C/iainlicr/ s
iounial, will interest students of nature. So long ago as 1866
a letter was published in Ihe .At/ie'itciim under the same title,
andatiracted Ihe notice of Charles IXtrwin. Hirdsofl'er, perhaps,
the best proofs of a feeling for beauty exterior to themselves
There are ihe Bower Birds of Australia, and the Gardener Bower

NO. 1315. VOL. 51]

Bird of New Guinea, each of which decorates its bower with
vari(ius objects. The Ilammerkop or Hammerhead also
nourishes esthetic tastes, and other instances of birds showing
a decided taste for oroainent are describel in the article
referred to.

-^ passing notice will suffice for the remaining articles on
scientific subjects in the magazines received by us. Some in-
teresting reminiscences of the late Oliver Wendell Holmes as
nrofes-or of anatomy, are given by Dr. T. Dwight in Scribiter.
Good IVonh — the first number of a new series — contains the
first part of a paper on Sir I-aac Newion, by Sir Robert Ball ;
and some speculations by the Rev. Canon Scott on the physio-
graphical consequences that would have resulted if the earth
rotated from east to west instead of west to east. Mr. Grant
Allen writes another " Moorland Idyll," in the English
lUiiilrated. To the Humanitarian, St. George Mivart
contribuies the concluding pait of his popular exposition of
the doctrine of heredity. We are glad to note that the second
number of the Plwnographic Quarterly Krjieiv contains several
scientific articles, each of which will help to familiarise phono-
graphers with scientific phrases. The Contemporary has an
article on Ihe London County Council, by .Mr. Sydney Webb,
in which the work of the Technical Education Board is inci-
dentally referred to. In addition to the magazines and reviews
named in the foregoing, we have received the Fortnightly,
Longman's, Cornhill, and the Sunday .Magazine ; but in none
of these is science given a place.

SEASONAL CHANGES ON MARS.'

FOR the substantiation of changes on the surface of Mars, it
is of paramount importance that the drawings to be com-
pared should all have been made by the same person at the
same telescope, under as nearly as possible the same atmo-
spheric conditions. So much, at least, is fulfilled by the draw-
ings referred to in this paper. For they were all made by
Mr. Lowell at the same instrument, under Ihe same general
atmospheric conditions. Even the different eye-pieces used
vary chiefly in a manner to minimise, if anything, and so em-
phasise the differences observed. For with increasing image
the higher power used tends lo decrease the contrast. The
result is that it largely offsets the difference in contrast due to
nearer approach, and leaves simply a case of magnification,
with the values untouched.

Since, furthermore, the drawings were all made in the months
preceding and following one opposition, secular changes are
practically out of the question ; and any changes that appear,
are presumably of a seasonal character. They constitute of
themselves a kinematical as opposed lo a statical study of
the planet's surface.

The resulting phenomena are much more evident than might
be supposed ; indeed, they are quite unmistakable. .\s for
their importance, it need only be said that deduction from them
furnishes, in the first place, strong inference that Mars is a very
living world subject to an annual cycle of surface growth,
activity, and decay ; showing, in the second place, that this
Martian yearly round of life must differ in certain interesting
particulars from that which forms our terrestrial experience.

The phenomena evidently make part of a definite chain of
changes of annual development. So consequent and, in their
broad characteristics, apparently so le^ular are these changes,
that it is not difficult to find corroboration of what appears lo
he their general scheme in drawings made at previous opposi-
tions. In consequence it will be possible in future to foretell, to
some extent, the aspect of any part of the planet at any given
time.

The changes in appearance presented by the planet described
by Mr. Lowell, refer primarily not to the melting of the polar
snows, except as such melting forms the necessary preliminary
to what follow-, but to the subsequent changes in appearance
of the surface itself. To their exposition, however, the polar
phenomena become inseparable adjuncts, since they are inevit-
able auxiliaries 10 the result.

With the familiar melting of the polar snow-cap, therefore,
this account properly begins, since with it begins the yearly
round of the planet's life. Wiih the melting of the Larth's
.\rctic or Antarctic cap might, similarly, be said lo begin the

1 .\lislr.ict of ii paper by Mr. Pcrcival Lu»gl', in .Ij/»otki«;j a;..<' .lj//v
/'/lyxics for December.

26o

NA TURE

[January lo, 1895

Earths anaual acti»ity. Bat there appears to be one important
difference here at the very ou'-et between the two planets. In
the else of the Earth, the r.luion of .he melun. of us polar
snows to the awak.nini; of surface acl.v.iy ,s 'jh'elly one of /«/
hoc simply ; in the case of Mars, U seems lo be one of propter
iZc L well For unlike .he Ear.h, which has water to spare,
Mars is apparently in straits for the ari.cle. and has to draw on
ts polar reservoir for its annual supply. To the mel..n>; of its
polar cap, and lo the iranslerence of .he water thus annually set
U<x to eo i.s rounds, seems to depend all the phenomena upon
the surface of the planet. ... • u j ..„j

The observations up .n which this deduC.on is based extend
over a period of more than ftve months ; from the l^t day ot
May 1894, to the 7th of November. They cover .he regions
■from the south pole to about la.i.ude thirty degrees north. It
is probable that analogous changes to those recorded, differing,
however, in certain m.arked particulars, occur s,. .\ art.an
months later in the planet's northern hemisphere. \ or though
it is likely that the general -ys-em is one f.r the whole planet,
it is also likely that the distribution of the planet s surface
details alter* the action to some extent. -. u ij

In order to appreciate the meaning of the changes, it should
be borne in mind that the vernal equinox of Mars southern
hemisphere occurred on A,>ril 7, 1894 ; the sum.ner solstice of
the same hemisphere on August 3> : and that Us autumnal
equinox will take place on tebruary 7.

On the -Slst of last .Mav, therefore, it was toward the end of
\pril on Mars. The south polar cap was then very large, up-
wards of 45° across, and already in active process °\^f:
ine The tilt of the planet's axis towards the Earth cnabed it
to be well seen, and disclosed the fact that it was bordered
persistently by a dark ban!, broader in some places than m
others, but keeping pace wiih the snow's retreat. 1 he average
breadth of the dark band was in June, 220 miles. It was the
darkest marking on the disc, and was i>lue. . . v ■ •,

As the season advanced and .he snow cap diminished, lis
dark girdle diminished in breadth, with fluctuations dependent,
doubtless, on the draining capacity of the ground. In August
il showed as a slender dark thread , ,_ , • t

This formation was water, beyond a doubt ; for il was ot
the colour of water, it faithfully l<.llo«-ed the melting of the
snow, and it suhs-quen.ly vanished-three independent facts
mutuallv confirmatory .0 (his conclusion. ,. .u .

That it was .he darke^^blue marking on the disc, implies that
it was the deepest body of water on ths planet. I hat it subse-
aaentlv entirely drained off, i.nplies that its depth could not have
been very great, lioih facts together make a fust presumption
in favour of its being not only the chief body of water on the
planet, but the only one of any size.

This polar sea plays deui c< machina lo all that follows.
So soon as the melting of me snow was well under way, long
strai's of deeper lint than .heir surroundings made their appear-
ance in the midst of the dark areas. They were al.eady there
on the last day of May. The most conspicuous of them lay
between Noachis and Hellas in the Mare Ausirale, and .hence
through the Mare Erythoru.n lo the Ilojr-glass Sea (Syrtis
Major). The next most conspicuous one came down between
Hellas and Ansonia. Although ihese straits were very
dislinguishably darker than the rest of the seas through which
they ran, the seas themselves were men at their darkest. 1 ne
fact that these straits ran through the seas, suffices to raise a
second doubt whether (he seas be seas. The subsequent
behaviour of the so-called seas renders their aqualic character

still more doubtful. ,

\t the initial stage of the Martian Nile-likc inundation, the
seas were at their darkest. This is probably due both to the
fact that some water had already found its way down from the
pole and also to the fact that moisture h.id been deposited there
on the water's journey up, and had quickened the vegetation of
those relatively amphibious lanris.

For some lime Ihe dark areas continued largely unchanged in
appearance ; thai is, .luring the earlier and most extensive part
of the melting of ihe snow cap. Alter this, iheir history
became one long chronicle of drying up. Their lighter pans
ercw lighter, and their darker ones less dark, t or even to start
wilh Ihey were composed of every grade of linl. Indeed, one
of :he mo»l significant features about them w.as that at this
epoch il was impossible to fix any definite boundaries to the
s^th temperate ch.iin of islan.ls. The light areas and ihc dark
ones merged indistinguishably into each other. Viewed from

the standpoint of maps of Mars, the landmarks of this whole
region lay obliterated by a deluge ; not directly, but indirectly.
Probably the region was in various stages of vegetal fertility in
consequence of a comparatively small body of water then
inundating it. The colour of the dark areas w-as then, and is
now, to my eye, a bluish-green ; quite unmistakably so. Ihis
tint Gradually faded out to give place to orange-yellow.

The first marked sign of change was ihe reappearance of
Hesperia ; this took place in July. It was not till the end of
October, on the 30 h, that Atlantis was caught sight of.
About the same time Ihe straits between the islands Zanthus.
Scamander, Ascanias and Simois, came out saliently dark, a
darkness due to contrast. . , • .

Meanwhile the history of Hesperia continued to be instruc-
tive From having been invisible in June, and conspicuous in
August, it returned in October to a mid-position betweeii the
two Vacillating as these fluctuations may seem at first sight,
they will all be found to be due to one progressive change in
, he same direction, a change that showed itself hr^t in
Hesperia itself, and then in the regions round about it. !■ rom
lune to August, Hespeiia changed from a previous blue green,
indistinguishable from its surroundings, to yellow, the parts
adiacent remaining much as before. In consequence the
peninsula stood out in marked contrast to the sl.U deep b ue-
Lreen regions by its side. Later the surroundings themselves
faded, and their change had the effect of once more partially
obliterating Hesperia. . ,, , .- j n ,1,.

While Hesperia was thus causing itself to be noticed all he
rest of the south temperate zone, as we may call it lor
ider.liftcali-n's sake, was unobtrusively pursuing the same
course Whereas in June all that part of the disc cn^Prising
ihelwoThvle, Argvre II. and like latitudes was chiefly blue-
nreen by October it had become chiefly yellow. The separate
identity of these islands became then for the first time apparent.
Still further south, what had been first snow and then water
turned to yellow land. This metamoM'hosis went on ti , on
October 13, the remains of the snow-cap entirely, or practically
entirely, disappeared-the first complete disappearance of U on
record After this event the whole south polar region was one

'"^Tow.ard 'the end of October a strange and, for observational
purposes, distressing phenomenon took place. What remained
o the more southern dark regions proceeded unexpected y to
fade in lint throughout. This was first noticeable m the C m-
merium Sea ; then in the Sea of the Sirens, and in November
^Te M.are Erythr..um ab.ut the Lake of the Sun. T his fading
sleadily progressed until it got so far that in ,,oor seeing he
rnarkings were almost imperceptible, and the planet presented
a nearly uniform yellow disc. . .

Now' this fading out of the dark areas is a highly significan
fact, with a direct bearing upon their conslitiuion. For U is not
simply Ihat portions of the pl.anel's su.f.ice have changed tint.
buTthat, taking the disc in its entirely Ihe amount of the blue-
green upon it has diminished, and that of 'he orange-ye o«
hroporliona.ely increased. Mars appears more Martian .u"
he did in June. Now, if the blue-green areas represent water
where has this water gone? Nowherconthev.sibled.se. Ilia.
Ts certain. For in that case Ihe amount of Ihe dark areas should
no'be perceptibly lessened-which 1. is. Nor can it all very
well have gine to that part of the planet that -^ "J''^" f °">
view For Schiaparelli's observations in .S82 go to show iha
^e northern snow-cap forms lale-one month aJUr the vernal
equinox of Ihe northern hemisphere on that year. Smcc. here-
?ore. the water fails to piove an Mi, presumption .^ 'nsiantly
a sid in favour of Ihe il.erna.e hypothesis, that the bluegreen
areas represent vegetation, fertilised by a co"M>aralively small
amount of water whose direct presence or absences " 't "'V
perceptible lo us, but whose indirect effects are. F «r vegetalioa
might change from green to yellow without requiring any cor-

"Tow Th^u^^'J^s^ffi^ofTh'/water may not be traced by
i.s amount. Ih'-cre isa'fur.hc'r change which has la.e ly appeared «"
the disc which hints al what lias become oi it I he canals have
darkened. What is more. Iheir darkening has P»rsued a per
fccily .lehnile course, proceeding steadily from south to no th^

•riie r.llowing observ.tiions show, first ih.al 'he canals are not
eq«.ally visible at all limes ; and secondly, that ihe.r invisibiUty
is a matter of the Martian seasons. , ■„ i„„,i The

In June the canals wc.e very f.a.nt markings '"d"''- "i=
least faini were those in Ihe Soils l.acus region. As the planet

NO.

I315. VOL. 51]

January io, 1895J

NATURE

261

approached us, they all became naturally easier to make out ;
but until October no change apparently occurred in any of them,
except those in the region about the Lake of the Sun. These
by September were already dark. In October they began to
show symptoms of growing lighter again. At the next presenti-
tion, in November, they showed further signs of change, though
not differing as yet very unmistakably in tint. Meanwhile, when
the .Sinus Tiianum region came round in November, I found that
its canals had begun likewise to darken. The canals were not
only darker relatively to the Mare Cimmerium and the Mare
Sirenum than they had been, but actually darker themselves.
In the next few nighrs the more northern canals about Ceraunius
had followed suit. They had darkened relatively to the southern
ones about the Lake of the Sun.

Now, on looking at a map of Mars, it will be seen that the
.Solis Lacus region is that part of the continental areas which
lies nearest the south pole. Similarly, that the region about
Sinus Titanum is the next farthest south. The matter of latitude
therefore atTects the point.

The canals and so-called lakes share, therefore, in the annual
metamorphosis, with a season change dependent in a general
way upon their latitudes. A wave of deepening tint passes suc-
cessively through the blue-green regions from south to north,
timed to the seasonal wave that travels from pole to pole. From
being pale in winter, their colour comes with the spring,
deepens through the summer, and dies out again in the autumn.
In any given locality the change comes early or late, in
proportion as the place lies, other things equal, dis'ant from
the pole.

That this change of tint is due indirectly to water, and
directly to the vegetation that water induces, seems probable.
For just as there is great difficulty in disposing of the water on
the first supposition, so the second would Irad us to expect just
the phenomena observed. It may ihercfore be cmcluded that
the formations known as the seas of Mars are probably midway
in evolution between the seas of F.anh and the seas of the
Moon. That is to say, they are not barren ocean beds, but are
in that half-way stage of the process when their liwlevel hel|)s
them catch what water still voyages upon the planet's surface,
though they have long since parteil witti their own.

Throughout all these inieresting chani^es that follow the
seasons across the face of Mars, there is but one feature ap-
proaching permanence — the great continental areas, lixcept
for a possible variation in brightness here and there, this great
area has remained unchanged. Like the reddish desert regions
of our Earth, its colour and iminuiability point to like character
for cause. It does not change because it is already past such
possibility. It is one vast desert waste.

UNIVERSITY AND EDUCATIONAL
INTELLIGENCE.

A NKW post has been created under the Education Depart-
ment for the purpose of obtaining -special intoimaiion and
issuing special reports, from time to time, in relation to
educational work at home and abroad. The fr. quenl demand
for fuller information on many educational sulgccis, and the
great increase of purely administrative woik, both at the
Education Department in Whitehall and at the Science and
Art Deparimeni, have made it desirable to have a separate
officer in charge of a small additional branch lor the above-
named purpose, who will be designa'ed " Diiec'or of Special
Inquiries and Reports." Thi~ appointment has been acccpied by
Mr. M. E. Sjdier, Student of Christ Church, and Secretary of
the University Extension Delegacy at Oxford.

The Technical Education Hoard of tne London County
Council will be prepared early in July, 1895, to award not
more than five Senior County Scholarships of the annu.il value
of £fio in addiiion to the payment of college fees, tenable for
three years, and subject to annual renewal. The schola^^hips
are intended to provi<le the means of obtaining advanced
technical training in a university, univer-ily college, or tech-
nical institute ol universiiy rank for slulenis (yung men or
women) of exceptional alulity who would otherwise find it im-
possible to secure such tr.iining Candidates must, as a rule,
be under nineteen years of age on September I, 1895, but the
Board is prepared to consider very special cases in ■ hich the
candidates are above thai age. The scholarships are offered
with the view of encouraging the study of science or art, with

special reference to industrial requirements, and will be tenable
at such institutions giving appropriate instruction within the
statutory definition of technical instruction as may be selected
by the scholars and apfiroved by the Board. In the selection
of scholars the Hoard will have regard, in the first instance, to
the past achievements of the candidates, but the Board
reserves the right to require any or all of the candidates to
undertake an examination if it think fit. No candidate will
be eligible whose parents have an income from all sources of
more tnan £i,<Xi per annum.

Since November 1893, the Technical Education Board of
the London County Conned have aw.irded 721 Junior County
Scholarships, each of the value of ;^20 and two years' free
schooling. More than three thousand candidates pre-
sented themselves in competition for the scholarships,
which are re-tricted to children whose parents are in
receipt of not more than £\y^ a year. A detailed analysis
of the occupations of the |>ersons whose children com-
pe'ed for these scholarships is given in the London 'lechnical
Ediicalion Gazelle. It indicates that the highest percentage of
candidates who received scholarships is to be found in the
leather trades, and next to these in the printing trades and
jewellery and fine instrument trades, .\fier these come the
artistic trades and crafts, but the most remarkable feature is the
comparatively poor results obtained by the children of clerks,
agents and warehousemen, and ih; very poor success achieved
by the professional cla-ses. The time is not far distant when
the scholarships granted by the Board will amount to the value
of /^30,ooo per annum.

SCIENTIFIC SERIALS.

The Mathentalical Gazette, No. 3, December, 1894. — The
eccentric circle of Boscovich. In this continuation the editor
considers a special case in which the centre of the eccentric
circle lies on the straight line whose points of intersection with
the conic are required. He then discusses the mttho 1 as one
of transformation, and finally poinis out a connection between
reversion and perspeciive projection. — Dr. Mackay, in Greek
Geometers belore Euclid, wiites upon Pythagoras and the
Italic school. — Cajori's " History of .\Iathcniatics " is an all too
short noiice, by Dr. G. B. Halsied, o( a book that has come in
for a fair amount of praise and blame There .ire some very
interesting problt-ms, solutions of examination questions, and
questions lor soluti >n. — Prof. .\. Lodge supplies an addition to
his previous article on approximations and reductions. — We
note, with pleasure, that in fuiure the Gaztlte is to be enlarged
to twelve pagts. This additional space will greatly help to
increase the use of this journal, which has so quickly made its
way in school circles.

Bultetiit of Hie American Mathematical Society (2nd series, vol.
i. No. 3, December, 1894). — The group of Holoedric Trans-
formation into it-elf of a given group, by Prof. E. II. Moore,
is a paper read before the Society at its November meeting.
The remaining article is by Dr. G. A. Miller, on ihe non-
primitive subsntuiion-groups of degree ten. A list of these was
given in the Quarterly Juurnal of Mathematics, vol. xxvii. pp.
40-42. A result ol ihe article belore us is that the following
six groups should lie deleli-d from that list, viz. 200.,, 200-, 200,,
10O3, 50,, 5O3. — In Ihe Briefer Notices short accounts are given
of 11. Hertz, ** Gesammclic Werke," liand iii. This volume,
the first one as yet issued, ciuit.iins a memoir on the principles
of theoreiical mechanics and mathematical physics, which was
composed during the last ihiee years of the author's life. The
next notice gives a sketch of a new edition of Grassmann'.s
mathematical works. It is to be hoped that, as w.as recently
suggested in Naiure by Pr if. Genese, a translation into
English of the AiiSilehniingslehre may soon be made, lor
the convenience of many suidenis in this country. The
other notices summarise the conienis of the Jahresbcrichte
der Detitschen Mathemntiker- I'ereiiiigutrg (vol. iii. 1893),
of the Proceedings of ihe /Vmeiican Association — for the forty-
second meeting, held .at Madison, Wis. (August, 1893);
of "Le Livrct de I'eiudiant de Paris" (Paris, 1894). — The
Notes comprise accounts of the November meetings of the
American and London Mathematical .Societies. By the way,
the reporter, who is a me nber of the latter Society, gives one
of the names of the Council incorrectly. There is also an ac-

NO. 1315. VOL. 51]

26;

NATURE

[January io, 1895 I

count of the meeting, in September last, at Vienna, of the
German Malh<;iiialical Association. The Bullelin well main-
tains its position, and closes with its useful lists of new
publications.

SOCrETIES AND ACADEMIES.

London.

Mathematical Society, Dec. 13.1894. — Afajor Macmahon,
F. R. S. , rrcsuient, aid suhsequcnily NIr. X. E. H. Love,
F. U.S., Vice-rresidcnl, in ihe chair. — The following cummuiii
caliiins were made: — On .MaxAell's law of partition of energy,
by Mr. G. H. Bryan. In liis recent report to the British Asso-
ciation, ihc author had shown ihai if a large number of dynamical
systems of any kind be taken, all similar in every respect, it is
always posMble to distribute their co 'rdinates and momenta so
that the distribution shall remain permanent, and shall satisfy
Maxwell's law of partition of energy. By this is meant that if
the kinetic energy of each system be reduced to a sum of
squaret:, the mean values o( these squares are equal. But the
a ilhor had duuhted whether it was possible in any case to inlcr
thai the lime averages ol the squares forming the kinetic energy
of a single S)stein were equal. In the preent p^per the con-
nection lie' ween lime azera^es, and av rages taken over a lar^^e
nuj'tber of diffireni systems, is examined more tully by means of
an artifice sugi;ested by Prof. Uolizmann's paper "O.i the
applicalim of the determinantal relation to the theory of poly-
atomic gases" (publi-hed as an appendix to Mr. Br)an's report).
Instead ol a vessel containing gas (as taken by Prof. Bolizmann),
any single dynamical system is taken whose coordinates and mo-
menta return 10 their oiiginal values after a long lime T. If the
time be divided into an infinitely laige number («) of infinitely
short intervals (;), we can derive a stationary dislribulion by
taking » systems and staiting them, the first at time o, the
second at time ;, the third at time 2i, and so on, giving e%'ery
system the same coordinates and momenta at the time of
starting it. At ihe end of the time T, we shall have the sy.slems
dislnbuiC'l according to a permanent or stationary law, and at
any sub-cquent instant the mean value of any function of the
coordinates and momenta lor the different systems will be equal
to the time average of the corresponrling func ion for the original
single s)Slem. If, however, we ilarl with a number of systems
distribu'ed according to a permanent law, we eaiinH pass back
to ihe original single system unless we can show that Ihe law of
fermancnt distribution is unique. Now in any simple lest case,
such as that afforded by rigid bodies movatile about fixed
points or particles moving in planes after the manner of a
Lissajou'., curve tracer, a stationary distrihution exists satisfying
Maxikell's Law of Partition, but other stationary distiil.uiicms
are possible which do not satisfy the law. lUnce the author
concludes that the time averages of the squares into which the
kinetic energy of a single system can be divided, are not in
general equal, at any rale inctependenily of initial circum-
stances.— Ihe Spherical Catenary, by Prof. A. G. Gieeiihill,
F.k.S. The pseudo. elliptic integrals developed in the I'roc.
L.M..S. XXV. are applied in this p.iper to the construction of
solvable cases of the spherical catenary, given by the relation

where

7. - (t - 2'')U - hf - A-

connecting i|i the azimuih, and z = cos 9, where 9 denotes the
angular distance from the lowest point of the sphere, the tension
being w{i - //) (Clebsch, Cretle, 57). Putting

and

X = * - /

' = /■

dz

/(' -
(I - ■■

•■) s/Z

then X can be idenllficd with the standard form of the pseudo-
elliptic of the third kind, of or ler fi,

_ ,fp(s - a) - MS/C - 2)

-'/

(J - ff) V S

NO. 13 I 5, VOL. 51]

'</',

where

S = 4t(j + .v)'- - [{y -f i)r + .(^'l-

by putting

X = I. / = if^ + aY A = M()' -1- I), h"- = .\^- 2j' - I,
^ V M '

where

W = - -'L±J.

2X

and.j-, ^ are Ilalphen's functions, defined in his " Fonctions
lilliptiques," I. p. 102. If « = a when : = i, and « = b
when c = - 1, then u = ^ [a - b) when : = h ; a and /' are
eich of the form/oij, a traction of the imaginary period ojj.
Also

M'p{a + i) =. - i(, - h^) - JA^
or I2p(a + i) = S.v— (j/ + 1)-, so that <r = o, and

a + b = f"-».

Thus, for instance, when

a + /' = 1B3, A = A- - I , / = i A ;
and the corresponding spherical catenary is given by

\' 2

With
and

With

\'

VI- :^" + (/'- 0^ +

■ i,a + b - Sttij, K- = h- ' I, / = ''A ;
z")'^'^' = A(!' - //c= - 2;) + i(hz + O^'Z.

then y ~ x = - c, suppose ;

and

(I - z-)-e'^

where

With

M= =

Hr'' -I-

-,/>= !'3 - '■)\I

+ H. + i(L:' + . . .+Lj)^/Z,

II

_ 2 - 5c -f f

M, L =

^h, &c.

o -f ^ = ~ai^
2

ihe calculation is rather more complicated, as this case must be
derived from ^ = 8 ; but the result is of the form

Jx>

.{Hz- H,)n'(S3-*- = -

with

+ «XLs - L,)x/(s

s,> 3>r,>Ji>«> «>3|ii

»0' *1> *!!■ *J 1

denoting the roots of the quartic Z = o. — The Trnnsformaiioo
of FJIiptic Functions, by Prof. .\. G. Greenhill, F.K.S. The
function z., introduced by Prof. Klein in his paper on the i
transform.ition of elliptic functions (/V(V. I. M.S. xi. p. JSOi '
and ileveloped in Klein and Fricke's " M.Mhillunctionen," il.
part v., is shown here to be connected with lialphcn's7 fuiiclion
liy the relation

p[ - lYz. = \»y.,
for a lr.in-furination of the Kth order ; and for an odd value of «,

p.

ti

U;
tflll

It

kt

y„ •f . t

AV+I = ■-■ , / = I, 2, 3.

■yn+j/ - 1

;; - I
2

in Ibis manner the relation 7,1 = o is satisfied.

The biquadratic relations satisfied by the function : are
now derived from Ilalphen's formula

Ym + nYm-.i = 7m ) l7>n-l'>'"" ~ •)"+ Tn-lT"

January io, 1S95]

NA TURE

263

The relation 7„ - o is treated a? the equation of a curve wiih
coordinate^ .V and y; and wtien f and y can be ex;>ressed as
functions of a puiaeter c, ths qaantities 7, and i, can also
be expressed as functions of this parameter. For instance,
7i3 = o reduces to the quadratic in p

/- - (I - c- - c')/ - <r(l + f)= = o

by means of the substitutions

.v = j{i ^ :), y = z{i - j), z = c\p- \);

and now in K'ein's Modular Equation of the Thirteenth Order,

given in the Proc. L. M.S. ix. p
\ - c - 4<r-'

1 26, it is found that

= - +

I

c- 3-

When one root t „ of this modular equation is given by
_ I3f(i + c\ _ 13

C \ -T C

the remaining 13 roots, typified by t,., are given by

(. + t-^'^ )

where o

4. S.

O, I, :

12,

(Klein, Math. Ann. xvii. p. 567).

It has been shown in the Proc. L.M.S. xxv. p. 252,

that

and now, putting

9 =

x'y*i

(<r=«r = -

J.1.J,-.

,16,10

(ff=,)"=*-^, (0-;,)" =

I all functions off and ^C, where

C = I + 4ir + dc" + 2f^ + i-i + 2c'' + t:".

The solution in the same minner of the Modular Equation of
the Seventh Order has alieady been given in the Proc. L.M.S.
xxv. p. 224 ; while the Kilth Order introduces Klein's icosa-
hedron function. A similar procedure will serve for the
Eleventh Order. — On certain definite iheia-function integrals,
by Prof. L. J. Rogers. — On a class of groups defined liy con-
gruences (second paper), by Prof. W. liurnside, F. R.S. —
Electrical vibrations in condensing systems, by Dr. J. Larmor,
F. U.S. It is only by the introduction of considerable c.ipacity
that the vibrations ol electrical systems of simple geometrical
form can assume a character at all simple and steady ; for this
reason it is of practical importance to be able to estimate the
periods of vibrations in the dielectric plates of condensers. It
lis shown that the modes and periuds for such a plate are pre-
Icisely the same as those of the acoustical vibrations of a plate
of air of the same form and the same law of thickness, enclosed
on both faces, and also round its edge, by rigid walls, the only
dilTerence being that the velocity of electric propagali n replaces
the velocity of sound. For example, if the condenser is a
spherical one, the period-, of the free vibrations are equal to the
lime required for an electric pulse to travel round its
ciicumference, divuled by (/«'- + «;'-, where m is any integer ;
and this result will also practically hold good for a con
denser of this form which is not a complete sphere, but has
a hole through it at the point oppoiie to the place where
the inner coating is connected with the exciter. The
leriods for a flat condenser of uniform thickness correspond to
the well-known ones of standing water-waves in a cylindrical
vessel o( the same form of contour. If a condenser is divided
iby cutting across its conducting coats, as is done in the ordinary
guard-rini;, the separate parts will vi' rate without interfering
'with each others periols. Various other cases are treated ; for
example, the propagation of electric waves in a compound

NO. 1315, VOL. 51]

plate composed, say, of air above and a liquid below. — On the
integration of Allegrei's integral, by .Mr. A. E. Daniels.— On
the complex number formed by two quaternary matrices, by
Dr. G. G. Morrice.

Linnean Society, December 20, 1894. — Mr. C. B. Clarke,
F.R. S., President, in the chair.— Mr. W. B. Hemsley ex-
hibited a series of specimens and figures illustrating parasitism
of Loranlhus aphyllus and other plar.ts, from the Herbarium,

Kew. Mr. J. E. Harting exhibited a specimen of a small

Siberian warbler, Phylloscopiis superciliosus. which had been
obtained near Beverley, Yorkshire, in October last, and made
some remarks on its haunts, habits, and migration, and upon
the previous instances which had been noted of its accidental
occurrence in the Britih Islands.— Mr. H. M. Bernard gave
the substance of a paper on the spinning glands in Phrynus,
not previously known, and described their position and their
morpholoi;ical importance in .\rachnidan phylogen. The penis
was described as a pair of rudimentary filamentous appendages
of the genital segment, and consequently of importance as
bearing further testimony to the view that the limbs on the
abdomen of the ancestral form were not plates as in Limulus,
but appendages like Ih se on the thorax. The presence of
these limbs explains the curious genital operculum of the
Pedipalfi, which is not a primitive feature derived from
Eurypterine ancestors, as some would maintain, but a purely
secondary specialisation acquired within the Arachnid phylism.
— .\ paper was then read by Mr. Percy Groon), enliil.d " Con-
tribunons to the knowledge of .Monocotyledonous saprophytes,"
or plants which are dependent for their existence on the pre-
sence in the substratum of decaying organic matter. He
obseived that, like parasites, they may be divided into those
which possess chlorophyll (Jicmis iprophyta) and those which
have none (holosapropliyles). Hitherto very few experiments,
he said, had been made on kemiiapri'phylts, and hence our
acquaintance with them was largely speculative. The remarks
which he had now to offer referred almost entirely to /;o/«ay»r£>-
phyles, or at least to plants with very little trace of chlorophyll.
Alter an interesting discussion, in which Sir D. Brandis, Mr.
H. N. Ridley, and others took part, the Society adjourned
to January 17.

Paris.
Academy of Sciences, December 31, 1894— M. Loewy in
thechair. — -^ study of<,;raphitcs liom iron, by M. Henri Moissan.
Al the ordinary pressure, the graphite is purer when formed at
a higher temperature. The graphite produced at the highest
temperature is the most stab.e in pre-ence of nitric acid and
potassium ch'orate. Under ])tessure, the crystals and masses of
graphite appear to have suffered incipient fusion. During the
solution of the cast-iron by acids, hydroxy compounds are
formed, which resist a dull red heat, but burn like the graphite
it-elf. — Report was made favourably on a memoir by M.
Riquier, to be printed in the Recueil Jts Memoircs da Savants:
itran^crs, under the tile " On the existence of inegrals in any
ditiereniial system, and on the reduction of such a system to a
completely integrable linear form of the first order." — On the
radial velocity of f Hercules, by .M. H. Deslandres. A
specirophotographic determination in which the line displace-
ments are measured on photographs taken with comparison
spectra on each side of the star spectrum. The mean value of
the radial velocity of this star is - 70 km., as deteruiined by M.
Belopolsky ; the author confirms this exceptional value, finding
-60 41, a second observer finds the velocity -62 97. — On the de-
termination of 1 he number of loots common to a sjsiein of simul-
taneous equations, and on the calculation of the sum of the values
of a function in these points, by M. Walther Dyck.— On the solu-
tion of numerical equations by means of recurring series, by M. R.
Ferrin. — On dehniie integrals of divisors, by M. N. Bougaief. —
On certain cundiiions to be realised for the measurement of elec-
trical resistances by means of alternating currents and the tele-
phone, by M. R. Colson. — On the sulphides of nickel and
cobalt, by M. .\. Villiers. This is a study of the c-jcdiiions of
precipitation ol nickel and cobalt sulphides, and ol the means
whcicby lie precipitation may be whidly or paitly prevented. —
On calcium ethoxide, by M. de Forcrand. Calcium carbide,
C,Ca, gives with ethjl alcohol compounds of the type
«CaO -f- M'CsHgO, and not an-elhoxide. The compounds
obtained are (I) 3CaO.4C.jH6O and (2) CaO.CJ IjO. At the
same time gas is disengaged, consisting chiefly ol acetylene (So
per cent ), and an easily liquefied elhylenic hydrocarbon (10 per

J64

NATURE

[January io, 1895

cent.). — On fl-oxycinchoninf, by MM. E. Junafleisch and E.
Lc^er. The preparation and properties of this compound aft
given in detail, and thirteen of its salf; are described. S-oxy
cinchonine is an energe'icdiacid base ; it turns litmus blue, and
reddens phenolphlhalrin. — .\c'ion of chh>rine on the secondary
alcohols, by M. A Brochet The action of chlorine on alcohols
of the type R.CIIOH CH, yields ke'ones of the form
R.CO.CCIj, the radical R i einc also chlorinated to the exien'
characteristic of the radical. — On the industrial preparation
and physiological properties of the oxalate and of the crystal-
lised salts o( nicotine, by MM. W. P.trenly and E. Grasset.
The mortal do»e of pure nicotine is 20-2I mgm. per kilogram
weigh! of animal. The fatal dose in the combined stale is
much larger. An animal slowly accttstonted to the action of
the p"ison can support daily a dose greater than thai fatal in
ordinary cases. — On pine tar, by Af. .\dolplie KenarH. —
Kemaiks on the muscles and brnes of the hind bmb of Hatleria
fuiulala, by M. .\. Periin. — Comparative stuHy of the lobed
and reticulated Rhizopoda of fr«-sh wa'er, by M. Felix Le
Dantec. — On the nests oi I'esf'a crahrn, L. ; oider of appear-
ance ol the earlier cells, by M. Chail-s lanet — The frai;men's
of the upnermost stratum of Ubaye, by MM. \'.. [laiig and \V.
Kilian. — On the conrluions of propigaiion of typhoid fever,
cholera, and exanihemalous typhus, by M. Renard.

New South Wales.

Linnean Society, November 28, 1S94. — The President,
Prof. Pavid. in the chair. — Rr-de-cnpiion ot A^piditgs ramsavi^
Macl., by Kdear R. Waiti-. — A revir-w of the fossil jiws of
the Afacropoiiiiue '\n the Queensland Museum., by C. W. He
Vis. The very tine collection of "ver i leven hundred dissociated
jaws or portions of jaws in the (Queensland Museum has been
studied in the light of a knowledge "f the nature and rantie of
ihe variations, indiviiliial and specfic, presented by the skulls of
479 individuals referable to sixteen < xi-tiny siieci'S The follow-
ing species were de-cri bed as ne« : Falorchfstes parvtis^Sthenurus
pales, S. orcas. Halmaliirus vinceus, H. thor, H. dryas, II.
oJin, H. indra, H. iiva, H. Vishnu. Macropus magister, M.
pan. and M. faunus. — Notts •"' snme I, and Pianarian^cullecied
byThos. Steel, Esq . on the Blue M .untains, N.S.W., by Dr.
.A. Dendy. — On a Biiiish bivalve mollusc found in Australia and
Tasmania, wtlh its disiril'Uii n ; and on a new sul>-genus of
Trochidii, by J. Bazier. — Ctyplodon Jlfxiiosa, Montagu,
was recorded for the first time Imm P rt .Sieiihens, N.S.W.,
and Esperance Bay, Tasmania. — The name Solauderia. Fischer
(1880), being preoccupied by Duchassaing and Michelotii
(1846), it was proposed 10 replace it by Rossiltria. — De>criplion
of a new Australian eel, by J. Douglas Of;iiby. — Gymndhorax
prionodon. sp.n., from Pnrt lack^nn. appearefl to be closely
allied to ihe .\llanlic species C oiellaltis — On a new Tvpbloi'S
previously confoundetl with 7. utis;uiroitris, Peters, by G. A.
Boulcnger, E. K..S. — Botanical n'nes (rem ihe Techm logical
Museum (part iii.), by J. II. Maidin and U. T. Baker The
writers gave a list, with localities, <f 1 lanis new to New Sou'h
Wales; also no'es on some rare or little kno^n plants
indigenous to the colony. — On n new species of EnWi'pneiula
from the coast of N- w South Wales, by James P. Mill. The
name/^/>'c<Oi/^raa«j/ra/iVHj<> waspiopos-i' f.ir the fir I dcscrib'-d
Australian species of Enieiopnensta. It is pecially charac'cr-
ised externally by the great development of the genital wings
which completely hide the gill area, and extend far into the
hepatic region, and by the piesence of two longitudinal
epidermal stupes overlying the two ciliated bands of the
intestine. In the mttdc of formation of 'h- probo-cis pore, il
appears to be the mfist variable of all Enferopneiiitii hitherto
described. The mtjst interesting prtints in its internal anatomy
are the presence of a median l.ngnu linal inf Ming of the
ventral wall of the heart blar(dcr into the cavity of the same,
the presence of a transverse vessel between the dilTeieni
proboscis vessels, and the much branched condition o( the
gonad". — On a Platypus emliryo (r>m the intrauterine eig
by J. P. Mill anil C. J. Martin. The embryo described was
taken from one of two eggs just ready |i> be laid. The eggs
mcasuicd iS mm. by ij'j — being somewhat larger than the
eggs descrilcd by Caldsycll. The emliryo inure nearly
resembled that of ihe Virginian uposstim (IJidelphys) ol
seventy-three hours, ilescnbed by Selcnka, ihan anv other
embryo known in ihe authors. The Platypus embryo is,
however, much longer.

NO. I 31 5. VOL. 51]

SOCKS, PAMPHLET, and SERIALS RECEIVED.

Books. — .\ Mono^ra|»li of the Mycetozi>.i: A. Lister (LonJon, Brit.
Mus ). — Rei^en in den Molukken : Prof. K. Martin. 2 Vols. Text and
Plaiesd.eiden, Brill)— Harvard College, by an O.xonian: Dr. G. B. Hill
(Macmillan).— Annuaire. 1S95, par le Bureau des Longitudes (Paris
Oauihicr-Villars). — La Fabricalion des Eaux-de-Vie; L. Jacquct (Paris,
Gaulhier-Villars).

Pa.mi-hlet. — An Essay on Southerly Bursters: H. A. Hunt.

Sbkials.- Natural Science. J.anuary (Rait).— .Astronomy & -\ktro- Physics
December (Wesley) — Journal of ihe Koyal Micrusconical Society, December
(Williams). — Bulletin de l.'Acade nic Impiriale des Sciences de St. Piters-
bouri:. September, Octr^ber, November (Sl Pitersbnnrg). — Bulletin of
the .American Malhcni.aiica] Society, Deceinber (New York, Macmillan).
— Humanitarian. January (Hutchinson). — Century Magazine, lanuary
(Unwiii). — C' ntempnrar>* Review. January *Isb ster) — Natural History of
Plants, Part 9 Kerner and Oliver (Blackie) — Fonnighily Review.
January (Chapman) — Stances de la Sociiitti Krai ,^-aise de Physique, i8g4.
3*" fasc. (Paris) — School Review. December (Ham-lton, New York). —
Zeitsrhrifi fur Physikalische Chemie, xv. Hand, 4 Hefi (Leipzig, Engel-
maon). — New Review, January (Heinem.ann). — Hiilletin de la Socictc
de Oc'ogiaphie, 3'' Trim. 1804 (Paris) — (leol 'ciral Magazine, January
(Diilau) — .Mind. J.inuarv(\^ illiantsl. — Nali 'ual Review, January (Arnold)
— Lornhill Magazine, January (Smith, Elder). — Ji>urnal of the Royal
Acriculcural Society of England, 'third Scries. Vol. v. Part 4. No. 20
(Murray). — Annals of Scottish N'atural Hist-'ry, January (Kdinburgh,
Douglas) — Iniernalionales Archiv (iir Kthnograohie. Band vii. Heft 5 anil
6, and Supplement zu Band vii. (Leiden, Biill). — (Juarierly^ Journal of
Microscopical Science. December (IJhurchill). — Kssex Naturalist, Nos. 6-
10, Vol. viii. (Chelmsford. Durrani). — Scrihner's Magazine, lanuary (S
Low). — Ph nographic Quarterly Review. No. 2 (Pitman) — Memoirs and
Proceedings of the Manchester Li'eraryand Philosophical Society, Fourih
Series, Vol. 8. Mo. 4 (Manchester), — Science Procre-s. January (Scientitin
Pre^s). — Round the World. Part 1 (Newnes). — Medical Magazine, January
(140 Strand).

PAGE

. 241
. 242
• 24J

244

244

CONTENTS.

The Origins of Art. By Prof. A. C. Haddon . . .
Forbes's Handbook of Monkeys By R. L ...
Birds of the Wave and Woodland. By T. D. P. .
Our Book Shelf:—

Goto: " Studies on the Ectoparasitic Trematodes of

Japan"

Mason: " Woman's Share in Primitive Culture" . .

Catch pool : " A Textbook of Sound " 244

Gelcich : "Otiica" 244

Letters to the Editor: —

On the Liquclaclion of (iases — A Claim for Ptiority. —
Prof. Charles Olszewski; Prof. J. Dewar,

F. K.S 245

The Term " Acijuired Characters."— Prof. E. Ray

Lankester, F.R.S 245

Boltzmann's Minimum Theorem. Edw. P. Culver-
well 24"'

Aurora of November 23, 1S94. — Prof. A. S.

Herschel, F.R.S 241.

Peculiarities ol P>)chical Research. — Prof. Oliver

J. Lodge, F.R.S 247

The Study of Cloud. (UluslntUd.) By W. E. P. . 24S

Sir Chatlts Newton, K.C.B 250

Notes J51

Our Astronomical Column : —

The Greater Nebula of Orion 25J

The I'ransit of Mercury 25,!

An Important A-leroid 251

Prof. Adams' Collected Memoirs 254

The Bird-Winged Butteiflies of the East. (Illus-

(tilled.) By W. F. Kirby 254

A New Element in the Nitrogen Group. By A. E.

Tutton 2S*

Science in the Magazines 2591

Seasonal Changes on Mars 259

University and Educational Intelligence a6l

Scientific Serials ?6'

SocieticR and Academies *8*'

Books, Pamphlet, and Serials Received 264

NA TURK

205

THURSDAY, JANUARY 17, 1895.

EPIGENESIS OR EVOLUTION.
2eit- iind Straitfragen der Biologic. Von Prof. Dr.
Oscar Hertwig. Heft i : Praforraation oder Epi-
genese ? GrundzUge einer Entwicklungs-theorie der
' Organismen. (Jena: Gustav Fischer, 1894.)

' I 'HE theory of preformation, or rather let us say pre-
i J- determination, as revived at the close of the nine-
i teenth century, is much more formidable than its prototype
j of the eighteenth century. Not only is it stripped of all its
j «arlier crudities, such as the doctrine of c-mboilement, but
i it is supported by a mass of evidence accumulated by the
researches of the last quarter of a century. Its funda-
mental assumption, that of the existence of minute,
qualitatively unlike, ultimate particles of living matter,
is strengthened, if not supported, by the analogy of
the atomic theory, and the observed phenomena of
mitosis accompanying the maturation of the ovum
and spermatozoon, and the subsequent acts cf im-
pregnation and segmentation have been skilfully
blended with the fundamental assumption in such
a way that they are made to seem to be a proof of
it. This strong position is now assailed by Dr. Oscar
Hertwig, who is in many respects peculiarly well fitted
to the task. He is the master of a simple, lucid and
logical style, he has himself been, in conjunction with
his brother, a pioneer in many of the discoveries on
which the doctrine of predetermination is founded, and
he has recently set himself to the task of verifying the
experiments of Roux and others, and of examining the
evidence which they afford for or against the doctrine
ivhich he attacks. His answer is unequivocal. The
phenomena of development are to be explained on epi-
.; enetic, not on evolutionary grounds, and the latter
n pothesis is contradicted by a number of well-ascer-
ained facts.
In an introductory chapter Dr. Hertwig refers to and
f pts Roux's definition of development, evolution, and
genesis, which may be repeated here, as they give
ision to terms which are often loosely used or little
erstood. By "development" is meant the origin
perceptible heterogeneity. Epigenesis means, not
crely the formal increase of perceptible heterogeneity
I a substance apparently similar but possibly extremely
iimplex, but a real increase of pre-existing heterogeneity,
evolution means, the becoming perceptible of pre-
;xisting latent imperceptible differences. Dr. Hertwig
oes on to describe the positions taken up by Weismann
nd Roux, and deals particularly with the former, who, as
e shows, regards the germ as a veritable microcosm, in
Inch every separate variable part which appears in the
nirse of the whole ontogeny is represented by a living
irticle ; on the characters of these particles the
liaracters of the parts of the adult organism, whether
jomposed of one cell or many, depend. The sum of
Mese particles forms the germ-plasm. Agreeing with
■ismann that a theory of heredity must be founded
ind brought into harmony with the cell theory (and
perefore rejecting the opposite view of Nageli), Dr.
Ilertwig proceeds to attack Weismann's fundamental

NO. 1316, VOL. 51]

assumptions. As he rightly says, the foundation and
corner-stone of Weismann's theory is the assumption of
differential or anisocleronomic' division of the cell
nucleus. All-important as this assumption is, there is
no foundation of fact to be found for it in all Weismann's
work. Instead we find purely dialectical argument, and
more than this, we find that Weismann has attributed the
most opposite characters to his '■ idioplasm," declaring
it, in one place, to be stable and unchangeable, in an-
other to be labile and changeable. But, Hertwig points
out, the facts are directly opposed to the assumption of
anisocleronomic division of the germ substance. In the
Protozoa the division is clearly isocleronomic, and we
know of no instance among them in which the act of divi-
sion, as such, is a means of producing new species.
Moreover, the numerous cases {e.g. Podophrya gemmi-
para) of complicated life histories among Protoza show
that the dissimilarity which may at first obtain between
the two products of cell division is no indication of per-
manent and essential difference. The case of the lowest
multicellular organisms is adduced as showing that in
these also the cell division is isocleronomic, for each cell
of which the soma of many of these organisms is com-
posed, retains the power of giving rise to the whole
organism. The phenomena of regeneration and hetero-
morphosis afford evidence that there are in the tissues of
many highly differentiated organisms cells, or groups
of cells, which retain, in a high degree, the power of
giving rise to new and complicated structures, and this
is particularly exemplified in cases of heteromorphosis,
which is to be distinguished from regeneration by the
fact that, in the former case, lost organs are replaced by
organs which differ in form and function from those
which were lost, or organs are, as a result of special
conditions, produced in abnormal positions on the body.
Under this head of phenomena of heteromorphosis, Dr.
Hertwig groups the extraordinary phenomena which
have been brought to light by his own researches and
those of Driesch and E. B. Wilson on the segmenting
ova of such different animals as frogs, echinids, and
amphioxus, and these observations have been extended,
since the publication of Dr. Hertwig's book, by the re-
searches of Prof Rafaello Zoja on the developing ova
of ccelenteratcs. Briefly stated, the results of these
experiments are as follows : In the case of echinids,
amphioxus, and ccclenterates, the first two, four, or even
eight blastomeres may, by suitable means, be isolated
without impairing their vitality. Each blastomere, in-
stead of giving rise to an incomplete embryo, or a portion
of an embryo, begins the developmental course afresh,
as it were, and produces an embryo perfect in all its
parts, but one-half, one-fourth, or one-eighth the size, as
the case may be, of the normal embryo. In the case of
the frog it was not possible to isolate the blastomeres ;
but Hertwig was able, by pressure, to so alter the seg-
mentation, that the normal relations of the blastomeres,
one to another, were completely changed, and yet a
perfectly normal embryo resulted. Unquestionably this
proves that, in the first stages of segmentation, at any
rate, the division of the germ substance is not differen-

1 The German words " elbplcich " and " erbunglcich " being untrans-
latable into English, I have coined the equivalents isocleronomic ODd aniso-
cleronomic from the Greek KA7)pdi'Ofios an heir. — G. C H.

N

i

266

NATURE

[January 17, 1895

tial but integral, not qualitative but quantitative, and
this undermines the most important of Weismann's
positions.

Very important are Dr. Hertwig's criticisms on the
doctrine of determinants, so sharply and clearly defined
by Weismann. This doctrine is inseparably connected
with that of the anisocleronomic division of the germ-
plasm, and it might appear that if the l.itter is disproved,
it is unnecessary to enter into a detailed criticism of
what depends upon it. But the criticism is not without
its utility, since. Dr. Hertwig shows us, the conception
of determinants is only an extreme instance of a false
conception of causality common in current biological
literature. Weismann has supposed that the ultimate
vital particles, which he calls biophors, are grouped in
the germ-plasm into " determinants," and that every
smallest cell-group in the adult organism which has
definite characteristics and a definite situation is repre-
sented in the germ-plasm, both of ovum and sperma-
tozoon, by a definite determinant. These last are so
arranged in the germ-plasm, and are endowed with such
special forces, that they are able, in the course of
ontogeny, to move at the right time into the right place—
this movement being effected by the almost purposive
anisocleronomic division of the germ-plasm. This very
definite idea is founded on an erroneous conception of
the relations between primordium (Anlage) and prim-
ordial product, which are supposed to stand in rela-
tion to one another as cause and effect. More or
less unconsciously, the biologist commonly assumes
that, because a given animal proceeds of ne-essity
from a given egg, there is an identity between
primordium and primordial product ; so much so, that
the developing organism is often spoken of as if it were
a self-contained system of forces, a sort of organic perpe-
tuum mobile. He overlooks the fact that for the fulfil-
ment of the developmental processes many other condi-
tions are necessary, without which the primordium could
never arrive at the condition of its final product. Between
the two there is clearly no identity, and it is false and
mischievous to suppose, as the older evolutionists did,
and the new evolutionists are again trying to make us
believe, that the perceptible heterogeneity of the last
stage of the developmental process is only the final ex-
pression of an invisible corresponding heterogeneity of
the first stage. Throughout the whole of the ontogeny
there is an exchange of material taking place, the adult
has arrived not only to its bulk, but to its complexity as
the result of metabolism ; inorganic material is perpetu-
ally changed into organic, and serves for the growth and
development of the primordia. It is true that the form
changes are constant and invariable for the species, from
a certain kind of germ a certain kind of animal is invari-
ably produced ; but is not this largely because, in the
ordinary course of events, the oviceil is always subject
to similar conditions of assimilation and excretion, and to
similar conditions of gravity, light, temperature, &c. .'
Throughout the course of organic develupiiient things
which were external are transformed into things internal,
and the primordium grows and ii changed at the expense
of the environment. In thus recalling to our attention the
fact that an organism is above all things metabolic,
that its growth and changes are the result of its metabolic
NO. I316, VOL. 51]

activity, and that its ultimate mass is the result of

assimilation, of the taking up and making an integral
part of itself of matter which was previously apart and
different from itself, Dr. Hertwig does a real service to
biology. He forces us back to the consideration that
physiology and morphology are not two separate and
independent lines of study, but that they are so closely
interdependent that no generalisations can be made on
the evidence of one kind of observation alone : they must
be supported by equally cogent argu ments from the other
side. The theories of the evolutionists are essentially
morphological, and in this they resemble the theories
of the last century, that they take no account of one
of the most wonderful of all vital phenomena, that
of metabolism, but strive to find an explanation of the
ultimate perceptible differences in form by asserting
that the differences were always there, and have only
expanded so as to become perceptible. Weism.inn's
attempt to deal with this question by assigning the
power of change as the result of metabolism to the
biophors, does not really offer more than a purely
formal explanation of the question, for what he pre-
dicates of the biophors may very well be predicated of
the whole cell. Our ideas of increase of complexity
as the result of metabolism are made none the clearer
by shifting the responsibility of the change, if one may
express oneself so, to subordinate parts.

It is indeed apparent, on rellection, that the characters
of the perfected organism are not and cannot be the
characters of a single cell — or even of a cell fusion such
as the oosperm— and the converse of this is true that the
characters of a cell cannot be the characters of the per-
fected organism. For what is a perfected metazoon or
metaphyte but an aggregation of cells of most numerous
and unlike characters.^ The characteristics of the per-
fected organism are the result of the correlation of
all its parts, of the relations of cell to cell and of
groups of cells to groups of cells ; and .ire we to
attribute to a single cell which has no relations charac-
ters which are essentially the results of the relations
of innumerable cells one to another .' 01 the importance
of the correlation of the parts of the perfected organism
we can have no doubt, nor can we escape from the
corollary that the ch.iracteristics of the organism reside
not so much in the cells themselves as in the aggregation
and interdependence of the cells, and if we may demur to
the suggestion of the colonial character of the metazoa
which is contained in the sentence, we must at least
admit much of the truth of Hertwig's statement (p. 85) :

" That the ovum is an organism which multiplies itself
by division into many organisms similar to iisell, and that
it is through the reciprocal action (WechseUvirkung) of
all these m.iny elementary organisms at each stage of the
development that the organism as a whole is gradually
and progre^sively established."

Dr. Hertwig institutes the comparison which was made
long ago by Herbert Spencer, between an organism and
a human society, and it is worth while mentioning his
illustration as showing his conception of the relations of
the cell to the organism. The organisation of a complex
human society, he says, is something new, and not to be
thought of as existing beforehand in the organisation
of an individual man. It is nevertheless founded in

January 17, 1895]

NATURE

267

human nature, but we cannot in gross, mechanical fashion
seek for the organisation of a society in the primitive
nature of man. In a like manner the character of the
perfected organism is founded on the nature of the cells
which compose it, but it contains in itself a new element,
a heterogeneity due to correlation and reciprocity, which
is limited by the specific nature of the cell substance,
but is not to be sought for as a specific constituent of the
substance of any individual cell. Starting from this
point of view, we may consider Dr. Hertwig's own doc-
trines which he sets forth in the second part of his work
entitled " Gedanken zu einer Entwicklungstheorie der
Organismen." Whereas Weismann seeks the cause of
the orderly development of the primordium in the pri-
mordial substance itself, Ilertwig considers that the
development of the primordium is dependent on con-
ditions or causes which lie outside of the primordial sub-
stance of the ovicell, but are none the less produced in
regular succession during the process of ontogeny. Such
are, in the first instance, the reciprocal relations in which
cells stand one to another in increasing degrees of com-
plexity, whilst they increase in number by division ; and
in the second place, the action of the external environ-
ment on the organism. The argument in support of this
proposition is given in so condensed a form that it is
almost impossible to give any part or abstract of it with-
out giving the whole. The following sentence is so im-
portant that it may be quoted at length, and the reader
should refer to the work itself for the rest of the' argu-
ment and the conclusion : -

" One of the most important and essential causes
of the appearance of heterogeneity in the course of
development is to be found in the specific power
of the ovicell, to multiply itself by division. From
this fact alone, that the nuclear substance is able, in the
course of most manifold chemical processes, to assimilate,
step by step, matter from the reserve material stored up
in the egg, and oxygen from the surrounding atmosphere,
it is able at the same time to evoke an ever-increasing
heterogeneity. The increase of mass of the nuclear sub-
stance involves its progressive division into 2, 4, 8, 16
parts, and so forth. But the division is again the cause
of a constantly changing spatial distribution of the sub-
stance. The 2, 4, 8, 16 and following nuclei which arise
by division give way to one another in opposite direc-
tions, and attain to new positions at definite distances
from one another within the limits of the egg. Whilst
all the material particles of the ovum were at first
arranged round the fertilised nucleus as a single centre
of force, they are now grouped around as many individual
centres as there are new nuclei, and they segregate them-
selves around these as cells. It is therefore clear that
the ovum as an unicellular organism, when compared
with the ovum as a multicellular organism, has aliered
Its quality to an important extent, and that merely by
the process of isocleronomic division."

This is what Hertwig calls the function of growth as a
form-producing principle. The other principles which he
invokes are the relations of the cells to external conditions,
or the function of their position, and finally the reciprocal
influence of the parts of the whole on one another and on
the whole, or the function of correlation. It is not to
be denied that these are principles of considerable
importance, and it may be said that their importance has
never quite been lost sight of, but they do not bring us
any nearer to thi explanation of the totally different
NO. I 316, VOL. 5 l]

reaction of apparently similar substances to the same
stimuli. What we want to know is why, when we place
under a hen her own eggs and those of a duck, and so
expose them to identical conditions, chickens and duck-
lings are hatched as unlike one another as may be. The
answer given, "the difference can be due to nothing else
than to the different nature the different micellar struc-
ture) of the substance,' is unsatisfactory, in that it is
only a restatement of the fact, and is not an explana-
tion at all. In attempting to give a more definite
account of the different natures of the egg substance,
Hertwig is obliged to take his stand upon much the
same ground as the evolutionists. " In the hen's egg the
species is present as fully as in ths hen, and the hen's
egg is as different from the frog's egg as the hen is from
from the frog." He is compelled to agree with the
evolutionists in assuming the existence of a specific, and
even of a very highly organised primordial substance as
a basis of developmental processes, but he claims that
his concept of this substance is different from and better
than theirs, in that he ascribes to the primordial substance
or germ-plasm characters which are congruous with the
concept and character of a cell, and does not ascribe to
it the innumerable characteristics which are only evoked
through the union of many cells and the concomitant
action of external conditions. The distinction appears to
be a slight one, yet on careful consideration it assumes
more important dimensions. Hertwig, if I interpret him
rightly, conceives of the germ-plasm as a substance of
many and definite potentialities. He does not attribute
this potentiality to one part, and that to another part of
the germ-plasm, but argues that as a result of multiplica-
tion by division the relations of the cells with their
contained germ-plasm are continually undergoing change,
both with regard to one another and to the environment.
In consequence of the dilTerent conditions thus induced,
this potentiality is evoked in the germ- plasm of one cell,
that in the germ-plasm of another, and so on in ever-
increasing grades of complexity. The differentiation of
any cell is the result of its position, which determines
which of its many potentialities shall be called into
action. It is the reaction of the living substance to the
stimulus which evokes a particular potentiality, which
brings about its form changes, and it may be supposed
that a profound form change following on constant action
in one direction incapacitates the cell in question for the
performance of any of the many other duties for which it
was primitively fitted. This conception is epigenetic in
that it admits the coming into being of a new heterogeneity
which was not pre-existent in the ovum as such ; th.^t
which was present was a capacity for certain kinds of
heterogeneity. \'ery different is the conception of the
evolutionists, who define the exact potentialities of the
germ-plasm, and assign each to a given material particle
or group of particles. The heterogeneity is already
present ; thenceforward there is no room for the increa:e
of complexity in response to external stimuli. Dr. Hert-
wig rightly saystliat Weismann's explanation amounts to
nothing more than a renunciation of an explanation. His
doctrine of determinants leads us into an invisible
world in which there is no foothold for research.
For this reason, if for no other, we should welcome
Dr. Oscar Henwig's invitation to return to the paths

26S

NA TURE

January 17, 1895

of epigenesis. A theory which has a formal answer
for every question, which regards everything that we can
see and lay hold of as predetermined and unalterable,
which relegates the causes of phenomena to the unseen
and unknowable — such a theory, if accepted as true, does
not stimulate, but stifles inquir>'. Fortunately it has had
the opposite result. It has not been accepted, and it has
developed an attack of a brilliant and overwhelming
character. All the best arguments which Dr. Hertwig
can bring against the theory of predetermination are
derived, not from simple observation, but from experi-
ment. A few simply conceived interferences with the
normal course of the segmentation of the ovum have
sufficed to strike down the doctrine of determinants. May
we not hope that an extension of these methods may
illuminate the regions which are still hidden from us .'
After all his attempts to supply an acceptable alternative
to Weismann's scheme. Dr. O. Hertwig makes a partial
confession of failure. To many his failure will seem
complete, and it must be so since the evidence derived
from experiment is as yet wholly inadequate. But his
attempts indicate the paths along which research may be
conducted, and he is very right when he claims, in con-
clusion, that it is the great merit of his conception of the
developmental processes, that it opens the gates once
more to research, with some brighter hope of results than
the formal theory of predetermination afforded us.

G. C. BotJRNE.

COAL-DUST AND COLLIERY EXPLOSIONS.

Coal- Dust an Explosive Agent, as shown by an Examina-
tion of the Camerton Explosion. By Donald M. D.
Stuart. (London : Office of the Colliery Manager, and
E. and F. N. Spon.)

IT is significant of the conservatism — not always
wholly disinterested- that surrounds an old-estab-
lished industry that, in spite of all that has been written
and said on the action of coal-dust as an explosive agent
during the last twenty years, we should still find people
persistently clinging to the belief thit the only possible
cause of a colliery explosion inustht fire-damp. It would
be amusmg, were the matter less serious, to note the ex-
traordinary hypotheses and absurd surmises to which the
believers in this time-honoured doctrine are occasionally
driven in order to account for the existence of fire-damp
in places where the common testimony of unbiassed
people affords no proof of its presence. The hard logic
of facts is, however, surely, even if slowly, undermining
the mass of prejulicc with which this question has been
surroun led, and we may hope that before the close of
the century the action of the Legislature will conipel
these people, whose obstinate unbelief Jeopardises men's
lives, to give practical heed, even more directly than at
present, to the teachings of intelligent observation and
inspection. The causes and conditions which le.id to
a colliery explosion are now so well understoo I that such
a cata^iriphe ought to be no longer possible If it does
occur, we must lay the blame on the m.inagement and
discipline of the mine, and it should not be difficult,
under these circumstances, to fix the responsibility.
V' . 1316, VOL. S I 1

The master of a vessel who carelessly navigates his
ship, is liable to have his certificate dealt with in a very
summary fashion. It does not avail him to plead that
his crew are picked from a class that is proverbially reck-
less and foolhardy, and that his " look-out," therefore,
was probably in fault. The Assessors take it for granted
that he has a proper knowledge of his business, and they
hold him responsible for the discipline on his vessel.
Public opinion demands that a mine-manager should be
treated in a similar manner. How difficult it is for the
the law, in spite of the length of its arm, to get at a
manager who has been guilty of culpable carelessness,
has been shown in more than one inquiry that could be
named.

As an illustration of the mental attitude to which we
allude, we may refer to a recent report on the cause of
the explosion at the .Mbion Colliery, South Wales, in
June last. All the circumstances connected with that
explosion seemed to indicate that it was due to the same
cause as that which accounted for the explosions at the
Park -Slip, Apedale, and Malago Collieries, viz. the
presence of coal-dust, and this conclusion was confirmed
by the report of the inspectors appointed by the Home
Office to inspect the colliery.

In a report prepared for the colliery proprietors by six j
engineers, we finJ that these gentlemen are unanimously I |
of opinion that the disaster was caused by an outburst of
fire-damp, and they have great satisfaction in stating that
no blame in the matter can be attributed to any of the 1 1
officials or employes. There is no wonder, in view of '
this conflict of testimony, that the men of the Rhondda
district should have demanded a fresh inquiry by the
Government into the cause of the disaster.

The changes of opinion among " practical ' men on this
question of coal-dust are very suggestive, and strikingly
e.xemplify the course through which a new truth has to run
when it is in conflict with the settled conviction of interested
persons. Like the course of true love, it does not run at all
smooth under these circumstances. The idea that coal-
dust could be the cause of a colliery explosion was, in the
outset, scouted as absurd. Then, as facts multiplied, the
dust was allowed to have a share in the catastrophe ; it I
aggravated the violence of a fire-damp explosion. Next,
the proportion of the fire-damp became smaller by
degrees, until it reached the vanishing-point. Now we
have reached the stage that all dusts are not explosive,
and the colliery manager is satisfied that his dust is not
as other men's dust, liven in the case of those who were
more receptive of the teaching of experiment and of
trained observation, the recognition of the real facts has
had to run the conventional course. First they were not
true, then they were not new, and we knew of them
before; for did not Faraday and Lyell tell us all about
the matter in the Haswell report.' In a question of this
kind, colliery management ought to be in advance of
public opinion. That it has not always been so in tlie
past, the history of coal-mining shows only too plainly. It
was the shock to public sentiment, caused by a succession
of disastrous explosions, which occurred in the early
part of this century, that indirectly brought about a
revolution in the art of coal-getting. People in the
colliery districts, who were witnesses of the terrible loss

January 17, 1895J

NATURE

269

of human life, and of the misery and destitution that
followed it, asked their fellows if this ought to be part of
the price to be paid for coal, and the answer was given
in no uncertain tones. Government inspection was in-
sisted upon, and, in spite of persistent opposition, even-
tually obtained. In the outset, the character of the
mspection was not always jwhat it should be ; but, little
by little, this has improved. We have a better trained
class of men sent out by the Home Office now than
formerly, and their hands have been gradually strength-
ened by the Legislature, although, perhaps, not to the
extent that is desirable.

Statistics show that this intelligent inspection is gradu-
ally making its influence felt. Tested by the ratio of
fatalities to number of men employed, and to amount of
material raised, there is a slow but decided iinprove-
ment. Of course, even under the most ideal system of
inspection, coal-mining will continue to be a hazardous
occupation ; but this at least we may hope, that the steady
sacrifice of looo victims a year, which that ruthless
potentate, Old King Coal, seems to demand, shall not
continue to be augmented by catastrophes tha* ought to
be considered as preventable.

Mr. Stuart's book is to be welcomed, therefore, as
adding one more link to the chain of evidence which
establishes the fact that coal-dust may be the most
important and, at times, even the only agent in bringing
about a colliery explosion. About a year ago an explo-
sion occurred at the Camerton Collieries in Somerset-
shire, the significant feature of which .was that it took
place in a mine wholly free from fire-damp. All the
circumstances connected with this explosion were
brought to the knowledge of Mr. Chamberlain's Com-
mission by Mr. Garthwaite, the general manager, and
were fully inquired into by H.M.'s inspectors. Mr.
Stuarts examination was made independently of the
official investigation, and it is satisfactory to note that as
regards the main conclusion there is absolute unanimity
on all sides. There can be no possible doubt, therefore,
that the explosion of November 14, 1S93, at the New
Collieries, Camerton Court, was due to coal-dust, and to
coal-dust alone, initiated by a gunpowder shot, and
most probably by what is technically known as a " blown-
out shot." Mr. Stuart's examination showed that there
were no "extraordinary circumstances'' present; the j
shot-firing was an ordinary operation, the presence of \
coal-dust was a normal circumstance, and the work was
being done by a competent man. "The angle and
declivity of the hole were such, that if the gunpowder
were expelled, it would directly strike the dust ; but it
was so placed in the judgment of an experienced miner.
... In the presence of this explosion, therefore, conjec-
ture upon the supposed innocuousness of a gunpowder '
shot in a dry and dusty non-gaseous mine is at an end."
Whilst we wholly agree with Mr. Stuart in this con-
clusion, we are not altogether at one with him in regard
to his explanation of the chemical process of a coal-dust
explosion. Mr. Stuart appears to be of opinion that a
coal-dust explosion is in reality only another form of a
gas explosion. The action of the heated products of the
exploded gunpowder is, he assumes, to cause the dust to
experience a kind of destructive distillation whereby
NO. 1316, VOL. 51]

hydrogen and gaseous hydrocarbons are formed, which
at the high temperature combine explosively with the
oxygen of the air of the mine. Whether there is any
necessity to invoke this distillatory process as an ex-
planation of the phenomena, is extremely doubtfuL
Without expressing any final ;opinion on this point, it
may be pointed out that no definite relation between the
bituminous character of the dust andjits " sensitiveness "
as an explosive agent has been established. The dry
mines of South Wales, where some of the most formid-
able explosions of recent times have occurred, 'yield a
dust which is relatively rich in carbon, and which affords
no very large quantity of gas on distillation.

We would commend this book to the thoughtful at-
tention of every colliery manager, with, however, the
reservation that Mr. Stuart's theories are not to be ac-
cepted as of the same value as his facts. So long as he
confines himself to the orderly arrangement and}analysis
of these facts he is on perfectly safe ground. The
weakest portion of the book is that in which the author
seeks to elucidate the chemical and physical phenomena
of a coal-dust explosion, by the application of imperfect
thermal data and of irrelevant chemical observations.

THE MODE OF LIFE OF MARINE ANIMALS.

Die Lebensweise tier Meeresthiere. Beobachtungen uber
das Leben der geologischwichtigen Thicre. Von
Johannes Walther. Zweiter Theil einer Einleitung in
die Geologic als historische Wissenschaft. (Jena :
Gustav Fischer, 1S93.)

THIS is the second part of Prof. Walther's projected
extensive geological treatise, the first part of which
— on the Bionomy of the .Sea — appeared some time ago.
Of the three titles given, the second, or subsidiary one,
seems best to describe the scope of the present book.
It is not. as might be supposed from the primary title,
a treatise on the physiology of marine animals — would
that it were I that is still a great desideratum in biology
— but is rather some observations on certain points in the
life-relations, or mode of occurrence, of certain marine
animals, viz. those which are of importance to the geo-
logist [and no less to the biologist] as being the present-
day representatives of former animals now preserved as
fossils. Walther's idea is that we must study the rela-
tions of organisms to their environment at the present
day, before drawing deductions from fossil remains"as to
the physical conditions of past geological periods. His
object is to lay a sound foundation of fact, as to the mode
of occurrence of particular sets of animals, upon which
to base an account of the history or development of the
events chronicled in the rocks. The idea is a sound
enough one, if not very original — it must surely have been
present, consciously or not, in the minds of various geo-
logical and biological writers — and the conclusions
arrived at, if really based upon a sufficiently large ac-
cumulation of statistics, will no doubt be a valuable
guide to the geologist in forming his opinions. The
book, if very complete in its series of facts, would also
be a useful reference work to the zoologist ; but it may
be doubted, on an examination of the lists given by

270

NA TURE

[January 17, 1895

Walther, whether they are a sufficiently exhaustive com-
pilation to inspire thorough confidence.

For example, the information as to the geographical
distribution of species is rather unequal, being detailed
in some cases, and decidedly meagre in others, as when
(ot La-^ena sulcata is given only "im Mittelmeer," and
when for Crania anomala the only north-west European
locality is the Clyde ! While, on the other hand, such
minute local detail is given as that Globii;erina bulloides
is not uncommon in the brackish water of the Dee from
Chester to Hilbre Island. A number of detailed criticisms
oftbiskmd might be made, such as the extraordinary
entry " Lafora, 450 faths." when several species of the
genus are found in quite shallow water. But probably
enough has been said to show that the lists are by no
means complete.

The plan of the book is, brietly. as follows : first, the
gaps in the palxontological record, and their causes, are
discussed ; then the following groups are treated in suc-
cession : Foraminifera, Radiolaria, Spongia, Anthozoa,
Crinoidea, Asteroidea, Echinoidea, Holothuroidea,
IJryozoa, Brachiopoda, Lamellibranchiata, Gastropoda,
Cephalopoda, and Crustacea. A few general questions
are discussed. The author alludes to the well-known
fact that some of the most abundant groups in the
sea are almost unrepresented in the fossil series,
and that even amongst animals with hard parts the
fossils of a particular bed might inadequately repre-
sent what had been the living assemblage at that
spot. He quotes Edward Forbes' account of the
natural history of a shell-bed off the northwest of the
Isle of Man, and his later observations in the .Kgean
.Sea, to show that even the fresh dead remains of organ-
isms on the sea-floor do not always correctly show the
relative abundance of the living species.

In each group, after a short account of the characters,
mode of occurrence, &c., there follows a list of genera
and species, with an indication of the distribution and
range in depth, compiled from Challenger reports,
monographs, and other sources ; but there is a want of
correlation and digestion of the facts, the nomenclature
is not up to date, and the same species sometimes occurs
several times under dilierent names ; (■..1,''. on p. 308,
Ophiothrix /ragilis di^'pc^ts three times under the names
Ophiocoma rostila, Ophiolkrix fnij^ilis, and Opiuolhrix
rosula, with a different range in depth each time. Occa-
sionally an animal is found in the wrong group altogether,
as, a Holothurian amongst the Asterids, and an Ascidian
in the Gastropods. However, Prof. Walther has brought
together a considerable amount of material which those
who are interested in the distribution of animals in the
sea, and the association of species to form "faunas"
characteristic of particular regions, will have to utilise.
For this the marine zoologists and the geologists will
no doubt be grateful, and will, with profit, confult the
lists ; but I fear they will :ilsi) sometimes regret that the
author had not taken more pains to digest his facts
and to correct his proofs. Many odd pieces of interest-
ing information arc given ; but there is still room in
some book on marine faunas for a detailed account of
characteristic assemblages of animals with as full a de-
scription as can be given of their physical surroundin^^s
and their variations. W. A. H.

NO. 13 16, VOL. 51]

OUR BOOK SHELF.

Elementary Qualitative Clicmical Analysis. By Prof.

Frank Clowes, D.Sc, and J. B. Coleman. Pp. iSo.

(London : J. and A. Churchill, 1894.)
Tables and Directions for tlie Qualitative Clieniicat

Analysis of .Moderately Complex Ati.Ytures of Salts.

By M. M. Pattison Muir, M..A.. Pp. 44. (London:

Longmans, Green, and Co., 1S95.)
Laboratory E.rercise Booi- for Chemical Students. By

E. Francis, F.C.S. (London : Blackie and Son.)

The first of these books is an abridgement of
Prof. Clowes' text-book on qualitative analysis, adapted
for use in the laboratories of schools and- colleges.
For the most part, the book is like a host of
others of the same kind. It differs from many
of them, however, in the fact that the first fifty
pages is devoted to instructions on the preparation of
apparatus, to experiments illustrating the prep.iration
and properties of certain gases and liquids, 10 deicrip-
tions of analytical operations, and directions for the
performance of ordinary processes of chemical manipu-
lation. Work of this character forms by far the best
introduction to a course of practical chemistry, and
it has an educational value, which is more than can
be said for mere test-tubing. On account of this and one
or two other notable features, the book will probably
take a permanent place among laboratory guides.

''These tables and directions'' (writes Mr. Pattison
Muir) "are intended for the guidance of students who
are acquainted with the principlesof qualitative analysis,
and who are able to make a qualitative analysis of a
simple salt, and of a mixture of salts containing not more
than a single metal in any one group, and three or four
of the common acids." The student who has passed
through an elementary course of practical chemistry is
frequently puzzled how to conduct an analysis of mode-
rately complex mixtures of salts and the commoner
metals and acids, or an analysis of metals and alloys.
Mr. Muir's book tells exactly what to do in such cases.
By following the directions given, it would hardly be
possible for the young analyst to go wrong. The pro-
cesses described are easily carried out, and are concisely
stated. A point worth noting is that the formula: of
solids are printed in heavy type ; of liquids or substances
in solution, in ordinary type ; and of gases, in italics.
This method of indicating the physical states of sub-
stances certainly possesses advantages. Altogether the
book is a handy and trustworthy manual for analytical
chemists.

The exercise book arranged by Mr. Francis has ap-
parently been designed to take the place of the labora-
tory nole-book. It opens with a few exercises in practical
chemistry, the experiments being brielly-somelimes too
briefly described ; and blank spaces are left for the
entry of results. Then come a set of analytical
tables, and a number of blank forms in which all the
steps in the analysis of a mixture of two simple sails are
indicated, 'Spaces being left for the student to fill up
with his inlerences. 'I'he average student of practical
chemistry works like a machine now, and we have no
doubt that these tables will be after his own heart, for
they only leave him to fill in his observations as if he
were answering the qvicstions in a census paper. The
book may ser\e to drill the student into carrying out his
tests in the proper order, but it will not benefit him
mentally.

Elements of Astronomy. By G. W. Parker, M.A.

(London : Longmans, Green, and Co., 1S94.)
This is one of the books in which astronomy seems to
be regarded as a subject which is to be studied much in
the same way as one would take up an additional book
of Euclid. It abounds in definitions, propositions, and

January 17. 1895J

NATURE

271

corollaries ; the diagrams of instruments scarcely give
any ideas of what they are intended to represent ; and
the descriptive part of the subject might have been
omitted without much sacrifice. The ground covered is
that which is ordinarily understood by an elementary
treatment of mathematical astronomy, dealing chiefly
with the considerations relating to the positions, move-
ments, dimensions, and distances of the various heavenly
bodies, but includes also some very scanty references
to their telescopic appearances. On the whole, the
various points are clearly, though shortly, e.xplained,
but there is much to suggest that the author would
be all the better for some little observatory practice ;
for example, his method of determining the angular
value of a micrometer by means of the sun (p. 48) is
scarcely practicable, and a sun-spot 13,000 miles long is
by no means to be classed as one of the largest spots (p.
68). It may be pointed out, also, that a single observer, by
observing at intervals of twelve hours, gets better results
for the parallax of Mars than two working in the way
indicated on p. 115. A ship's mean time at sea, too, is
usually determined by one observation near the prime-
vertical, and not by the method of equal altitudes.

In less than a dozen pages the author attempts to give
an idea of the classification of the stars, and of "the
principal discoveries which have been made in modern
times, chiefly by means of spectroscopic analysis, with
their nature and physical condition ' (p. 203). The
omission of the solar prominences in an account of the
phenomena of a solar eclipse, is a good indication of the
very feeble character of this chapter.

The book is intended specially for students preparing
for University examinations, and by such it may be
found useful.

LETTERS TO THE EDITOR.

[The Editor does not hold himself responsible for opinions ex-
pressed by his correspondents. Neither can he undertake
to return, or to correspond with the writers of, rejected
manuscripts intended for this or any other part of Nature.
No notice is taken of anonymous communications.]

Exploration at Ruwenzori.

rp.RH.^PS it may interest your readers to give a short account
of Ruwenzori, where I have now ^pent four months. The
mountain is a very difficult one to study, on account of the
difficulty of reaching the most interesting part. Taking a sort
of botanical section from the shore of the Albeit Edward
Nyanza, one finds first a scries of gra'^sy plains covered with
Andropogous some two feet high, and in certain months sup-
porting large herds of elephants. Kudu, and Lurw.iU ante-
lopes. This is in part the old level of the lake, and in part
gravel and sand brought by the numerous rivers ; in places it is
doited by -Vcacia and Ihe iree Euphorbia, which has something
of the appearance of an enormous chandelier. After leaving
this plain, one comes to a series of small hills from 4000 'o
5000 feet in height, which have been apparenily cut out of the
mountain by the numerous riveis and streams. Some of these
are covered wiih patches o( culiivatiun, banana plantations,
&C. ; usually these are hidden from the main road. When one
reaches the mountain proper, one finds up to 7000 feet a steep
ascent covered with grass and small shrubs, usually three to
four feet high. The valleys in this part are usually very steep
V-shaped trenches, and cultivation is abundant everywhere,
sometimes over 7000 feet, and in the Wakondja country the edible
Arum is grown up to 7400 feet or more. This heighi, 7000
to 8000 feet, marks the beginning of the forest. Ii is composed
of deciduous trees, someiimes with a very thick undergrowth ;
sometimes it is pretty open, with a profusion of fern and moss
on the old trunks, and creepers in some places. I have found
tree ferns and Hegonia, but usually the flowers are rather pale
in colour, or quite inconspicuous. At 8(>oo feet another distinct
change takes place, and a wilderness of decaying young and
mature bamboos replaces the trees. Here and there these are
hung with creepers, but the predominant feature is the wetness of
everything. Moss covers almost every trunk below, and amongst

NO. 13 16, VOL. 51]

the rools are only very watery plants, such as Urticacete. At
9600 feet anolher change takes place ; bamboos disappear ccm-
(ilelely, and tree heather I akt sits place. In a drypartof ihemoun-
lainonefindsa charming little violei, a Cardamine, Galiums, Epi-
lobium, Rubus, &c. In wetter places one finds a regular peal-moss
with Sphagnum, beautiful orchids, and short heather ; in another
place one will find enormous trees of heather, usually gnarled
and twisted in growth — tree Senecios, tree Hypericums, &c.
This region seems to extend to the snow (which, I am sorry to
say, I have not been able to reach). On my highest attempt, I
could see the heather trees apparently higher than the snow.
On anolher attempt to get to the summit, I found what seems to
me .■Itchemilla alpina'. One feature of the mountain is the
extreme scarcity of animals and birds. In the lower forest there
are bushbuck, baboons, and two other sorts of monkeys ; one
the magnificent black and white-furred kind from which grena-
diers' shakos were made, and another with short slatey fur, which
is new to me.

Peihaps the commonest birds are the sunbirds ; one green,
yellow, and crimson, I have seen above 10,000 feet, and 1 have
also seen (though 1 am almost afraid to say ii) a robin, and a
goldfinch.

.\s 10 the geology of the mountain, I do not care to risk an
opinion at present, but I have taken many specimens which I
hope may solve some of the que-lions. I think glaciers must
have extended seven to eight miles down two of the valleys, but
there was no evidence to my mind of any extensive glaciation.
I think I am right in saying that the Salt Lake is nothing but
an extinct volcanic crater, and in several places along the east
side of the mountain there are others, or a smail chain of vol-
canoes ; usually the chain radiates from the centre of the
mountain.

I hope to start to-morrow for Ujiji, my object being to see
whether a practicable route exists from Tanganyika to the Albert
Edward Nyanza. I only hope I shall be able to bring my col-
lections saely home. G. F. Scott Elliot.

Salt Lake, Ruwenzori, August 2, 1894.

The Alleged Absoluteness of Motions of Rotation.

I MUST confess that discussions upon mathematicil meta-
physics appear to me to be somewhat unpractical. They are
suggestive of the case upon which Serjeant Snubbin was en-
gaged, which related to a right of way " leading from some
place which nobody ever came from, to some other place which
nobody ever went to." Nevertheless, I propose to offer some
remarks upon this subject.

That aiW;//^ motions of translation and rotation exist appears
to me too clear for argument ; but whether our senses are
capable of taking cognisance of them and reducing them to
exact measurement, is quite anolher matter. The view
advocated by Prof. Greenbill appears to be that motions of
rotaiion are determinate — that is to say, they are capable of
exact measurement within the limits of experimental error ;
v/hereas the contrary is the case with motions of translation.
Mr. Love, on the other hand, holds that neither kind of motion
is determinate in the above sense. Now a knowledge of the
absolute value of the velocity of translation of any object in-
volves a knowledge of the magnitude and direction of the sun's
velocity in space ; and until the latter has been determined,
which has not yet been done, the former is necessarily unknown.
It therefore follows that all motions of translation of which our
senses are capable of taking cognisance are relative.

On the other hand, the motion of rotation of any oV"ject is
independent of the motion of translation of the sun or any other
body. If, therefore, it were in our power to construct a system
of axes which either move parallel to themselves or whose
angular moiion is known, it «ould be possible to determine ihe
absolute value of ihe angular velocity of any object. liut even
if it were possible to devise an experiment by which such a
system of axes could be obtained, our results would only be
accurate within the limits of experimental error. It may,
therefore, be well to point out that, without inventing any new
experiment, the angular velocily of any object may be
accurately determined within the limits of experimental errorxn
the following manner.

.Select two stars, X and V, whose proper motions are so
minute ihat they have never been detected by the most refined
observations. Through the sun and the two stars draw a plane,
S X V, and through the sun draw a line, S /., perpendicular to

272

NATURE

[January 17, 1895

this plane ; and lee the mstioa be referred to S X, S Z, and a
line perpendicular to them as axes. Now in consequence of the
proper motions of the sun and the two stars, these lines will n')t
constitute a system of ates which are either fixed in space or
which move parallel to themselves ; consequently, if these lines
be taken as axes of reference the observed (or calculated) value
of the motion of rotation of any object will necessarily be
relative to these axes, and its absolute value cannot be deter-
mined without ascertaining the angular motion of the axes of
reference. But since the two stars have been specially selected
from amongst those whose proper motions have eluded de-
tection, the angular motions of the axes will be so small com-
pared with ordinar)' standards that the error caused by neglecting
them will lie within the limits of experimental error. If, for
example, we were to endeavour to calculate by the above
method, or some similar one. the ahs.^lule angular velocities of
the hands of a clock, or of a fly-wheel, the value which we should
thereby obtain would be as exact as the existing state of
mechanical and instrumental appliances admits.

A series of observations extending over several thousand
years might of course reveal a proper motion of any two selected
stars ; but in the case of angular motions whose periods do not
extend much beyond a century, the above method leads to
results which are for most practical purposes exact.

I am therefore disposed to think that all motions of rotation
of which our senses are capable of taking cognisance are
relative; but with the exception of certain astronomical motions
of very long periods, the absolute value of any motion of
rjtation which can be observed may be accurately determined
within the limits of experimental error. A. B. Basset.

Fledborough Hall, Holyport, Berks.

The gist of Mr. Love's long letter, on pp. 19S-9, seems to be
that since the specification of a force or a moti on depends upon
th; choice of axes, therefore the force or motion itself is
similarly dependent. A slight extension of the same principle
would make a velocity — say the velocity of light — depend upon
whether it was to be expressed in miles per second or in centi-
metres per hour ; and no extension at all is necessary to make
it depend on whether it is referred to Groombridge 1830, or to
some more quiescent body, if indeed the term quiescence may
b: allowed henceforth to have any meaning.

Tycho Brahc is said to have held that there was only a question
of language between the Copernican and the Ptolemaic systems ;
bat, with the exception of a semi-ironical Church compromise
attributed to Descartes, he has been unfortunate in not finding
a disciple of importance until the present moment.

It appears now to be equally true to say that the earth rises
to meet a stone, as to say that a stone falls to meet the earth ;
and considerations of energy are of no consequence !

I just want to add one word of my own on the subject, to
the effect that whereas the position of a body in an infinite
homogeneous stagnant ocean would be unmeaning and un-
specifiable, except by reference to boundaries or other bodies,
yet it does not follow that the rxlocily of a body through such
an ocean would be either unmeaning, unspccifiable, or un-
discoverable by experiment. It may be replied that such
motion would still be relative to something ; and to that I say
by all means, but it is not relative to other bodies such as are
competent to fix position, which is what Mr. Love is contend-
ing for.

As to the other question, about absoluteness of rotation, I
shall be much interested in seeing what Prof. Grecnhill, and
with him Frofi. Mach and Karl Pearson, have to say on the
point Oliver J. Lodge.

Liverpool, December 29, 1894.

The Quarrying of Granite in India.

At Bangalore, in Southern India, the quarrying of granite
slabs by meansof wood fire has been brought to such perfection,
that an account of the method may not be out of place. The
rock is a grey gneis-ose granite of very irregular composition
through unequ.il segregation of hornblende and the presence
of numerous felspathic veins. But it is otherwise very compact,
and forms solid masses uninterrupted by cr.icks for several
hundreds of feet. Only near the surface- the rock is found split
parallel to the surface. In one quarry there is thus, for in-
stance, a 4 feet thick horizontal layer of ralher weathered rock,

NO. 131 6, VOL. 5 r ]

underneath this another layer of fresh rock 3 feet thick ; but
below this the rock is entirely fresh, and not split. These
layers are probably due to the variations of temperature, daily
and seasonal.

The undisturbed rock is quarried by means of fire, and it is
remarkable what large plates may be detached. I saw one
plate of 60 feet greatest length, and 40 feet greatest width, and
half a foot thickness. This thickness varied only one inch over
the greater part of the area. The whole plate had been de-
tached in one piece by means of wood-fire, .\fterwards the
plate was cut with blunt chisels into strips of 2ji feet width.
So easily are these strips and slabs obtained, that it is quite
common to see palisades of them used instead of boundary
walls, and also to see them used as posts for huts, for telegraphs,
and for railings and posts in gardens.

In one case, I observed the operation of burning over an area.
A narrow line of wood-fire, perhaps 7 feet long, was gradually
elongated, and at the same time moved forward over the
tolerably even surface of solid rock. The line of fire was pro-
duced by dry logs of light wood, which were left burning in
their position until strokes with a hammer indicated that the
rock in front of the fire had become detached from the main mass
underneath. The burning wood was then pushed forward a few
inches, and left until the hammer again indicated that the slit
had extended. Thus the fire w,-is moved on, and at the same
time the length of the line of fire was increased and made to be
convex on the side of the fresh rock. The maximum length
of the arc amounted to about 25 feet. It yvas only on this ad-
vancing line of fire that any heating took place, the portion
which had been traversed being left to itself. This latter
portion was covered with the ashes left by the wood, and with
thin splinters which had been burst ofl". These splinters were
only of about ith inch thickness, and a few inches across.
They were quite independent of the general splitting of the
rock, which was all the time going on at a depth of
about five inches from the surface. The burning lasted
eight hours, and the line of fire advanced at the average
rate of nearly 6 feet an hour. The area actually passed over by
the line of fire was 460 square feel, but as the cr.\ck extended
about 3 feet on either side beyond the fire, the area of the entire
slab which was set free measured about 740 squ.ire feet. All
this was done with, may be, about 15 cwt. of wood. Taking
the average thickness of the stone at 5 inches, and its
specific gravity as 2 62, the result is 30 lbs. of stone quarried with
I lb. of wood.

The old quarries have sloping sides formed of steps left by
each successively split plate, each new plate extending to within
about 2 feet of the step left by the preceding plate. Many plates
are taken out in an inclined position, and as the directions of in-
clination dilTer, it follows that the action of the fire is quite
independent of the original surface of the rock, and also of the
direction of lamination and of the numerous veins in the rock.
The action of the fire is thus very similar to that action which
produces dykes and faults 0:1 a large scale, more or less
independent of the nature of the rocks which are passed
through.

The great uniformity of the thickness of the slabs formed by
the above process is probably due to a regulating influence of
the pre-existing crack. When the action of the fire is some-
what slower, it takes longer for the heat to penetrate down to
the crack ; when the action is quicker, there will be enough ex-
pansion produced in the upper layers, and the lower layers
transmit the tension to the plane of the crack. IV-rhap-i it will
be possible some day to measure the temperature of the heated
rock, when a certain agreement ought to be found between the
tensile strength of the rock and the strain which the expansion
by the heat produces in the so-far elastic rock.

Bangalore, December 19, 1894. II. \V.\RrH.

Storm Statistics at Bidston.

The Liverpool Observatory, erected at Bidston, on the
Cheshire side of the estuary of the Mersey, stands on a
slight eminence about 200 feet above the sca-lcvel. The ascent
is tolerably steep on each side except from the south, and with
the Irish Sea on the north, and Ihc rivers Mersey and Dee on
the east and west sides respectively, there is nothing to obstruct
or diminish Ihc force of a passing slorm. .Self-recording ane-
mometers of the Robinson and Osier types have been in position
since 1SO7, and it is from the records of these instruments that

January 17, 1895J

NA TURE

273

these statistics have been prepared. How far these records are
absolutely correct is beside the preie.it question ; all the data
have been obtained with the same instruments, and are strictly
comparab e between themselves.

It has been the custom at the observatory to treat as storms
or gales, all oc:a-ion5 in which the Robinson anem:)meter re-
corded the horizontal velocity. of the atmosphere as equal to or
exceeding fifty miles an hour. The total number of instances
in the twenty-eight years under consideration is 321, or an
average slightly below one a month. Iiwill frequently happen
in stormy periods that the critical velocity will be registered,
and be followed by a partial lull in the storm, to be succeeded
by gusts of greater force. If these periods of comparative calm
have lasted for about twenty-four hours, the disturbance would
count as two storms, although probably both are parts of the
same atmospheric disturbance.

The greatest number recorded in a year is in 186S, when no
less than twenty-eight gales were reported ; and the leait occurs
in 1880, when there were only two, and these neither long in
continuance nor great in violence. It is not without signifi-
cance— though, of course, it is not intended to insist upon the
coincidence — '.hat when the number of storms is plotted as an
ordinate with the time for abscissa, a rough curve can be drawn
among them giving maxima at practically equal intervals of five
years, from 1868, with minima at intermediate dates. Or, if
we take the sumsof the maximum years 186S, 1873, 1S78, &c.,
it is found that in the six we have records of eighty three storms ;
while in the six years of minimum, 1871, 1875, 18S1, &:., we
have only thirty-seven. •

It is scarcely necessary to refer to the direction in which
storms approach the observatory, after w'jat has been said of its
geographical position. Roughly, they are all from the west,
with slight deflec.ions to the north and south. As a matter
of fact, only five have deviated from this rule, and they have
been either east or south-east, anl have been comparatively
slight in their character.

The time scale on which the velocities havo been registered is
not a very open one. The recording drum mjves through
rather less than one inch in an hour, and the habit has been to
read and record the distance travelled from the commencement
of one hour to the beginning of the next. The maximum hourly
velocity is, therefore, not to be understood as the greatest in
any sixty consecutive minutes, but as the greate';t in one wh^le
hour as marked by the clock. \\\ this sense the following table,
which exhibits the number of times the greatest hourly velocity
has exceeded noticeable amounts, is to be understood : —

Recorded hourly

velocity

in miles.

No. of instances

50-60

220

60-70

68

70-80

21

80-90

10

Exceeding 90

2

Here again, curiously enough, we find some slight evidence
in favour of a five-year period. Not only do the two instances
of the greatest velocity recorded in the observatory occur in
years already noticed as those of maximum disturb ince, but
the average velocity of all storms in the years 186S, 1S73, &j.,
is 592 miles, as ompared with 57'9 miles in the years of
minimum number.

Intimately connected with velocity, though probably a less
accurate measure of the true force of a storm, is the pressure
recorded per square foot. Here Bidston has long held a record
for the British Isles, having placed to its credit a pressure of
ninety pounds on M.irch g, 1871. Tiie accuracy of this measure
has often been questioned, and probably it is too gieat owing to
the momentum in the moving parts of the machmery, but it is
certainly the record of a far greater pressure than has ever been
witnessed since. Considering over what small areas these
excessive pressures are exercised, and the great variation that
exists from moment to moment in the velocity of the wind when
a storm is raging, it is not an impossible amount, but it would
certainly be misleading to c mclude that such a pressure was a
measure of the force of the wind a fe.v feet, or even a few inches,
away from the pressure-plate. The hourly velocity on the
occasion when this pressure was registered has frequently been
exceeded, without reproducing similar pressures. Herein is
represented tlie great difficulty in determining a simple relation
between pressure and velocity, or, rather, the square of the
velocity ; for one may regard Hutton's law of wind-pressure on

NO. 13 16, VOL. 51]

a given obstructing surface as satisfactorily proved. The fact of
such accidents as that referred to destroys any value that can be
drawn from averages, but as a mere matter of fi^'ures, it appears
that the average m iximum hourly velocity for all storms is
584 miles, and the mean of the maximu.n pressures 37 '6 lbs.
This would require the factor for maltiplying the square of the
velocity in miles, to obtain the pressure per square foot, to be
greater than one-tenth, which is evidently anl necessarily
erroneous, since we are comparing the accidental momjntary
pressure with the average velocity obtained throughout the
entire hour. Taking the extreme pressures for what they are
worth, the numbers come out as follows : —

Pressure in lbs. on sq. ft. Number of instances.

20-30 132

30-40 HI

40-50 50

50-60 ... • II

60-70 12

On two occasions the pressure registered was greater than
70 lbs. to the square foot, and on three did not reach twenty.
Since the extreme pressure, are in a sense accidental, a ad do
not represent with any accuracy the force of a storm, it does no;
seem desirable to determine the relative pressures in whu have
been called years of maxima n and minimum storm occurrence.
But the general features are again borne out. Tne expla la'.ion
here is probably that the greater the number of storms the
greater the chance of finding a high pressure. It seems more
profitable to inquire what is the av.-rage length of a storm, how
long may a violent disturbance ht expected to last. This
question is unfortunately complicate 1 by the fact already alluded
to, that a storm may subside for a few hours and then reappear
with its original violence. If the interruption is only for an
hour or two, as already explained, the depression is considered
as one, but only those hours are counted in which the registered
velocity exceeds fifty miles. There are only two instances in
which this amount of violence has been maintained for thirty
consecutive hours, viz. in February, 186S, and again last Feb-
ruary. The total number of stormy hours in thj twenty-eight
year, is 1732, giving an average of 5 '4 hours for each storm.
Our local disturbances are therefore not of long duration.

An examination of the dates when gusty weather is most pre-
valent, goes neither to substantiate the ancient myth of the equi-
noctial gales, nor to uphold the evil supremacy which has long
been assigned to the winds of March Since no attempt has
been made to equalise the lengths of the months, February has
been somewhat unfairly treated in the following table ; but
notwithstanding this handicap, it possesses the unenviable
privilege of compressing within its shortened limits more tem-
pestuous weather than any other month.

... vT r . No. of stormy

Month. No. ofstjrms. . ,,^ '

hours.

January ... .. 47 ... ... 260

February ... ... 42 ... ... 2S1

March 47 238

April ... 14 63

May ... 7 27

June 3 19

July 7 21

August 17 65

September ... ... i6 ... ... 77

October ... ... 26 ... ,. 180

November ... 44 ... 254

December .. .. 51 ... ... 247

Total 321 1732

Of course one would expect to find the greatest number of
storms in the winter ; but that three-fourths of the whole should
be compressed within five months of the year, is a greater dis-
proportion than was expected. Th:; variations of the barometer
during these storms, and the dependence of this variation upon
the direction of the wind, are of considerable interest, but may
not very well be entered upon here while treating simply of
numerical statistics. William E. Plummer.

Peculiarities of Psychical Research.

Mr. Di.\'in asks in his first letter: Coald an abnormil dis-
tribution of the cards aflfect the result, if certain precautions
were taken? In his second letter he says there was nothing in
his first letter to indicate that he under-estimated the import-

-74

NA TURE

[January 17, 1895

ance of "abnormal distributions." Well and good, if the
S. P. R. have rot underestimated the importance of examining
the actual distribution of cards cut and of cards guessed, they
will have kept a record of each card cut and each card gues-ed,
card for card. If they have not done so, then their experiment
is scientifically of no value ; if they have done so, then the
analysis of the distributions of the cards cut and the cards
guessed ought to have accompanied any publicaiion of these
experiments. It is an obvious, but by nc means suffuient,
condition for a proper experiment. If the Secretary of the
S.P. R. will place in my hands the actual analyses of the cards
cut and the cards guessed made by a competent mathematician,
fiefon the publication in their PivceeJiiigs of the card guesses,
and proving that they did at that time fully consider the point,
and take this obvious precaution against deception, my estima-
tion of the "scientific acumen " of the S.P. R. will at any rate
on this point be modified.

I, of course, do not refer to my friend Prof. Edgeworth's
investigations, which do not touch the question of the distribu-
tions of cards cut and cards guessed. Kaki. I'karson.

May I call attention to Prof. Lodge's method of "silencing"
me in your issue of January lo. It bears very closely upon this
question of the effect of psychical research upon the investigator's
reasoning. He quotes the preface of Mr. Podmore's book to
show that that gentleman is not a "bigoted upholder of the
certainly of telepathy, " and the casual reader would scarcely
guess that, in truth, I never asserted that he was. I complained
of the very air of ojien-mindedness in that preface to which
Prof. Lodge's quotation witnesses, and showed by an instance,
that in the body of the book question-begging occurred
which was all the more dangeio.is on account of the liberal
tone of the opening portion. I made no o'ljection to the
individual prosecution of psychical research — only to its public
recogtiition before it has produced more definite results than it
has done so far. So much for the " silencing. " It shows either
that I'rof. Lodge has not read my review, or that he has mis-
understood it ; and in either case it enforces my contention that
these investigators are over-hasty. The phrase "irresponsible
detractor," points in the same direction. H. G. Wells.

The Suspended Animation of Snakes.

In Naturi; of December 6, p. 12S, Mr. G. E. Hadow asks
whether the snakes feign death for protective purposes, with
intent to deceive, or whether the strange action is the result of
a general nervous inhibition, produced redexly by the action of
flight, which would render it more or less analogous to a
faintingfit. He and others of your readers will be interested
in an additional observation that, in a measure, answers his
question. The snake, a "hognose," "spreading adder," or
"blowing viper," IletcroJon flalyrhinus, upon which Dr. L.
C. Jones based his note in Naturk, November 29, p. 107, the
origin of the discussion, was presented to me about live months
ago. While in my possession it has repeateily verified Dr.
Jones's statements ; and, besides, it has proved that it does
not depcml upon the feint alone. The latter is preceded by
another action that apparently has not been published hitherto.
After being teased a little, the animal, vigorously bending from
side to side, the tail abruptly raised and the vent slightly pro-
truded, begins to smear itself over the back with urine and
excrement, the odour of which is so excessively nauseous that
observcfs are quickly driven back, the better satisfied if they
escape without a spatter in their faces. If the teasing stops
with thi<, the victim glides away lo hide ; but if still more
worried, it lakes up the contortions that end in the trance-like
condition, lasting ten minutes lo half an hour, or until the
creature feels that it may safely revive. The specimen still
lives, and does not discard its filihy habit on prolonged ac
quaintance Much handling and familiarity with annoyance
make little difference in behaviour, or in disposition lo take
advantage of the peculiar tactics. In the inception of the
habiti lliesc actions most likely were >lae to terror ; possibly the
trance was a real faini ; but, however their utility may have
been diicovere<l, it is evident at the present time th.at confidence
in them as means of securing immunity from torment induces
their practice on occasions when the existence of actual fright
is hardly possible. At such times it would be difficult to
<:onvince witnesses that the <.nakc is not intelligently employing
what i( knows lo be its best mciliKiK of protection.

Cambridge, Mass., Dec. 27. 1894. S. Garman.

NO. 131b, VOL. 51]

I DO not think that Mr. Vincent can be right in supposing
that the suspended animation of grass snakes has nothing to
do with simulation. I have never observed it in the c.ise of a
snake when unmolested in a glass case (as he has), though I
have kept hundreds so, but noticed it first when catching snakes
in the New Forest. After much struggling and the usual offen-
sive methods of defence had proved vain, one has, in several
instances, suddenly hung limp and apparently lifeless on my
hand. It could hardly be a faint or anything but death-feign-
ing, for as soon as I put it on the ground, or allowed it no
longer to feel my hand, it recovered at once, and was off like a
shot. I took particular pains to test this, as I was much sur-
prised at the circumstance, which I did not lemeuiber having
seen mentioned in any book. In all cases it w.as a dernttr
ressort, the ejection of food and the effusion of smell having
preceded. W. Kknnedy.

"Finger-Print" Method.

Is my letter on the subject (Nati'RE, December 27, 1S94,
p. 199), I have introduced my assertion of the old Japanese
usage of the " thumb. stamps " on legal papers, with a qualifying
clause — " although at present I have no record to refer to.
Continuing in my search, I have come across a passage which
gives confirmation to the statement. It is in the /■'liw/.'ii Gu'ahi\
No. 50, p. 6, 1 okyu, February 10, 1893, where the details of
the bastinado inflicted on criminals during the ancicii rfgime
are given, and reads as follows : — " When the criminals* guilt
was ascertained, aiW they signed with ' thiimh-stamps ' on papers
in the Court, they were sent to prison with the m.agistrate's
words, 'Sentence shall follow,' which they used to understand
as the signal of the approach of the day of punishment."

December 31, 1S94. Kumagusu Minakata.

A White Rainbow.

The white rainbow is so rare as to deserve noting. One
was visible at Westnewton, Aspatria, for more than half an
hour on Saturday, January 5. The band was much broader
than in the ordinary bow, and the arc w,-is formed in the upper
intermediate cloud drift. This drift consisted of a light
pallium of irregular cirro cumulus. It is important to observe
that cumulus was forming, from above, at the time ; i.e. the
cirro cumulus was melting and descending into ordinary
cumulus. A patch of this cumulus formed (under observation)
and crossed beneath the bow. It then became coterminous
with the western section of the arc, which blended with the
cloud, and was of similar tint. Hard, dry frost continued and
lasted till January 13. Uarometer steady at time.

Samuil Harber.

Westnewton, Aspatria, January 9.

P. S. -Connote with the above the condition of the weather
on the Continent ; also violent thunderstorms on following day
in Cornwall ; also snowstorms in Cumberland and Scotland
within few days. — S. H.

AMERICAN TOPOGRAPHY}

■VVTE have it on the authority of Prof. Gannett that, at
' "^ the present rate of progress, the series of topo-
graphical maps of the United States, which was com-
menced in 1.S82, will require no less than fifty years for
completion, and that the cost of this great undcrt.iking
will not fall f.ir short of twenty million doll.irs. The map
is primarily intended to meet the needs of the geologists
of the Survey ; but it has been thought economical to
make such arrangements tliat the resulting map may be
ade(|iiate to serve all purposes for which general topo-
graphic maps are used. Its scope is limited to the
representation of the larger natural features, and the
artificial features which are of general or public interest,
to the exclusion of those which are purely of a private
character, and therefore liable to rapid changes.

In the vast area covered by the I'nited .Slates, there
is a great diversity both of natural and cultur.il features,
and the e.xtent of the survey and the scales of the maps

' " United Slalei Geological Survey. A Manual of I'opoKravhic Mclhods."
By Henry <j.inncll. Cliief TupDuraphcr. (Waihinijion : Government
Prinlins Ollice, 1893.)

January 17, 1895J

NA TURE

^11

are varied accordingly. The scales adopted at the com-
mencement of the work were I : 62,500, i : 125,000, and
I : 250,000 ; or very nearly i, 2, and 4 miles to the inch
respectively. With the progress of industrial develop-
ment, the maps came to be in great demand in connection
with all sorts of enterprises in which the nature of the
ground required consideration, as in the projection of
railways, water-works, drainages, and the like. Maps on
a larger scale, and showing more detail, have in many
instances become necessary, so that it has been deter-
mined to altogether discontinue the four miles to the inch
map, but only to make new maps of the areas already
represented on this scale in cases where they are specially
required. It is believed that on the scales of one and
two miles to the inch, it is possible to represent with
f.iithfulness all necessary details.

The relief of the maps is represented by contours, or
lines of equal elevation ; in the larger scale maps the
intervals range from 5 to 50 feet, and in the smaller
ones from 10 to 100 feet, according to the nature of the
area mapped. For the now discarded scale the intervals
are from 200 to 250 feet.

The methods adopted in the preparation of these maps
form the subject of the twenty-second monograph of the
Inited States Geological Survey, which constitutes an
excellent manual of topography. It is not intended as
an elementary treatise on surveying, nor as a general
treatise on topographic work, "although it may, to a
certain e.\tent, supply the existing need of such a work.''
It is primarily intended for the information of the men
actually engaged upon the survey ; but we believe that it
will have a much larger field of usefulness.

We may look upon this manual as consisting of two
essential parts : first, that dealing with the methods
employed in the surveys ; second, that giving a brief
account of the origin of the various topographical
features. The latter part we hope to refer to on another
occasion, and for the present it is sufficient to say that
its object is to act as a guide to correct delineation in
filling in the details of the sketching.

A map, whatever its character, is defined as a sketch,
corrected by locations. " The work of making locations
is geometric, while that of sketching is artistic, and how-
ever numerous the locations may be, they form no part
of the map itself, but serve only to correct the sketch,
while the sketch supplies all the material for the map."
Hence, the education ofthe topographer, as Prof. Gannett
tells us, should consist of two parts, the mathematical
and the artistic. " The first may be acquired from books,
and this book knowledge must be supplemented by
practice in the field. The second, if not inherited, can
be acquired only by long experience in the field, and by
many can be acquired only imperfectly. In fact, the
sketching makes the map, and therefore, the sketching
upon the Geological .Survey is executed by the best
topographer in the party, usually its chief, whenever
practicable to do so.

In making a map, four principal operations are in-
volved, (i) Astronomical observations for locating the
mip upon the earth's surface; (2) the horizontal location
of points ; (3) the measurement of heights ; (4) the
sketching ofthe map.

With regard to the methods now employed, " it is to
be understood that they are not fixed, but are subject to
change and development, and that this manual describes
the stage of development reached at present. ' Five
principal instruments have been employed in the Survey :
theodolites of a powerful and compact form, for use in
the primary triangulation ; plane tables of the best type
with telescopic alidades, for secondary triangulation and
height measurements ; plane tables of simple form with
sighted alidades, used for traversing and minor triangula-
tions ; " odometers," for measuring distances ; aneroids,
for the measurement of details of heights.

NO. I 3 16, VOL. 51]

All these instruments arc described with sufficient-
fulness, while other instruments, such as transits, chains,
tapes, and telemeters, which are commonly figured and
described in all works on surveying, receive no special
attention.

A single instrument of a very convenient form suffices
for the astronomical determinations of position. This
is a combined transit and zenith telescope, and consists
of an ordinary transit instrument provided with a zenith
micrometer eye-piece, and resting on a graduated circular
base in such a way that the whole instrument can be
made to revolve when using it as a zenith telescope. The
telescope has an aperture of two and a half inches, and a
focal length of twenty-seven inches. We are not ac-
quainted with any other instrument so convenient for the
double purpose of finding latitudes and longitudes with
accuracy. E.xamples ofthe observations made with the
instrument are given, and these, with the various steps
in the reductions, form an admirable guide to the astro-
nomical work.

Triangulation is employed in preference to primary
traversing wherever the country presents sufficient relief
for the purpose, as it is more accurate and cheaper.
The initial step in this process is, of course, the measure-
ment of a base line, and in our British survey this was
accomplished by Colby's compensation bars. This
method of measurement was also employed in the United
States up to 1S87, when it was decided to adopt a system
of measurement by steel tapes. The tape in use has a
length of 300 feet, and it is claimed that it is easy to
obtain the re(|uired degree of accuracy in a far shorter
time and at much less expense. A special apparatus for
using this tape has been devised, and full instructions
for its use and reduction to standard are given.

The description of the base-line measurement is natur-
ally followed by hints as to the selection of stations and
the erection of signals for triangulation. .\ very con-
venient form of observing tower, or combined mstrument
support and signal, for use when surrounding objects
have to be overlooked, is figured and described. We
learn that vernier theodolites have now been discarded
in favour of others in which the circles are read by
micrometer microscopes, although the circles are only
8 inches in diameter. An excellent and concise account
is given of the various errors to which angular measure-
ments are liable, and ofthe methods of eliminating them
from the final results. Some of these errors are instru-
mental, others personal ; and in this connection. Prof.
Gannett remarks that, " after learning how to make good
oDservations, the observer should place the utmost con-
fidence in them, and never yield to the temptation of
changing them because they disagree with some preced-
ing observations. Such discrepincies are in general an
indication of good, rather than poor, work."

In some districts it is almost impossible to carry on a
triangulation, and in such cases primary traverse lines
are resorted to, these simply differing from ordinary
traverse lines in being more elaborately and carefully
executed. These traverse lines, it may be said, consist
of a series of measurements of distance and directions,
and when they are intended to replace the triangulation,
they are made with the steel tape, to which reference has
already been made, and theodolites.

The account of the secondary triangulation is remark-
able chiefly for the great prominence given to the plane
table. Speaking of this, Prof. Gannett says that " much
misapprehension exists, especially in this country [the
United States], regarding the character and application of
this instrument. This arises, apparently, from the fact that
it is little known. For making a map the plane table is
a universal instrument. It is applicable to all kinds of
country, to all methods of work, and to all scales. For
making a map it is the most simple, direct, and economic
instrument ; its use renders possible the making of the

276

NATURE

[January 17, 1895

map directly from the country as copy, and renders un-
necessary the making of elaborate notes, sketches, photo-
graphs. &c., which is not only more expensive, but pro-
duces inferior results." As the instrument is perhaps
not widely known in our own country, we may say that
it consists of a drawing-board mounted on a tripod in
such a way that it can be levelled, turned in azimuth,
and clamped in any position. At the centre of the board
is pivoted the alidade, consisting of a ruler with a gradu-
ated bevelled edge, to which is attached a pair of sights
for rough work, or a telescope for work of a higher class.
A small graduated arc is provided in the better-class in-
strument for the measurement of vertical angles, but the
horizontal directions are plotted directly, by means of the
alidade, on a sheet of paper stretched on the board. The
edge of the board is set in the same direction when the
instrument is in use at ditierent points in the area being j
mapped, and horizontal locations are thus readily
determined bv intersections. '

LIFE A T THE ZOO)
A SIGN of the increasing interest shown by the out-
■^*- side world in all questions concerning life, and
more especially animal life, is evidenced by the far
greater number of books published every year on popular
natural history.

The past year witnessed the commencement of
several large works, such as the " Royal Natural
History," edited by Mr. Lydekker ; the republication of
" Jardine's Naturalists' Library,' edited by Dr. R. B.
Sharpe : and the " Cambridge Natural History," of
which, so far, only one volume has appeared, liesides
these there have been issued a number of smaller works
not extending over so wide a ground.

The present volume consists of a number of shot'
articles on various natural history topics more or less
directly connected with the Zoological Society's tiardens,
illustrated with reproductions of some of Gambier Bolton's
successful photographs of the animals found there. A

li',, I. — The Tieer listening to s -ft mu^

The -.imple form of plane table is now exclusively
used by the .Survey for the ordinary traverse work. Dis-
tance measurements in this class of work are made in
the usual way by counting the revolutions of a wheel,
an "odometer" being used for this purpose.

The manual abounds in practical hints on the various
points connected with surveying, and concludes with a
brief account of the office work which is so important a
supplement to work in the field.

The numerous appendices consist of tables to be used
in the various computations, and are complete enough to
include even a table of logarithms.

It is not too much to say that Prof, (iannett has pro-
duced a manual which will be of interest to many not
actually engaged in surveying, while at the same time it
forms a very valuable supplement to the ordinary works
on the subject. A. lowLEk.

NO. 1316, VOL. 51]

considerable number of these sketches have already
appeared before in the pages of the Spectator, but many
chapters have been added, and the whole forms a very
agreeable repertoire of gossip, with, in some cases, pre-
tensions to higher things in the shape of accounts of ex-
periments on the xsthetics of the animal world.

One of the most interesting of the articles directly con-
nected with the Zoo is that on " IClephant I-ife in
England." The number of elephants now in F.urope,
chiefly in circuses and men.-igeries, is considerable. ."Vlr.
Cornish gives it at .about 120, of which England possesses
about thirty-four. With some half-dozen exceptions, all
these elephants belong to the Indian species, and arc
mostly imported from Burma, where they are bred in a
half-wild state. The African elephant, according to our

' " I^ife at the Zoo. Notes .ind Traditions of the Regent^ Park Gardens.
By C. J. Cornish. 8vo. (London : Seeley and Co., tS^^s.)

Januarv 17, 1H95]

NATURE

277

author, does not appear to possess quite so even a temper
or so docile a nature as the Indian species, but still,
judgintj from what has been done with them in our Zoo-
logical Gardens, there seems to be no reason why they
should not be caught and tamed exactly in the same
manner as their Indian relatives. Indeed, a few years
ago an officer, in the service of the (German colony of
" East Africa, made a special tour in India for the purpose
of investigating whether it would be possible to intro-
duce the keddah system into East Africa. Whether this
enterprise has ever come to anything, does not appear to
have transpired. It is also known that
the subject occupied the attention of
General Gordon shortly before his death.
In an article on the Wild Cats of
the Zoo, Mr. Cornish discusses the
origin of our domestic tabby. Be-
sides the European Wild Cat {Felis
catus), which now appears to be
increasing slightly in numbers in
Scotland, owing, doubtless, to the in-
creased reservation of so much of the
area of that country for deer-forests,
he suggests the Chaus Cat of India and
Northern Africa as a possible ancestor
of our domestic form. There are, how-
ever, two other species, which both seem
in many respects to have greater claims.
One of these is the Cat of North .-Xfrica
{Felts caffra or inaniculatd), a species
held in veneration by the ancient
Egyptians, large quantities of the mum-
mified remains of which have been im-
ported to this country for manure. .An
argument in support of the opinion that
this is the true ancestor of the domestic
cat, is the fact that the sole of the hind-
foot of this species, like that of most
varieties of domestic cats, is black, and

not spotted, as in the European Wild

Cat {Felis cati/s).

Another possible candidate for the

ancestry of the domestic cat is the

Waved Cat (Fclis fon/iiatd) ; this cat

has been obtained in various parts of

India, but is never very common. It

resembles very closely the Indian

domestic breed. It is, however, more

than probable that whatever the origin

of the domestic cat may have been, it

has interbred with the wild cats of the

various countries to which it has been

conveyed by man. This has certainly

been the case in India, where hybrids

between the native domestic cats and

both the Jungle Cat {Fe/is chaus) and

the Leopard Cat {Felis bengalensis) are

fairly well known.

.V plea for the repeal of the absurd

and oppressive Act of Parliament that

prohibits the use of dogs for draught

purposes, forms another short essav.

This .Act was based entirely on the if

priori and ridiculous argument that

dogs " were not created " for such a purpose. Mr.

Cornish shows that on the Continent, where dogs are

freely used in this way, no ill effects ensue to them, and

that their employment is an enormous boon to the poorer

classes, who are unable to afford horses.

Several chapters of this work are devoted to the in-
habitants of the Reptile House at the Zoo, and among

them is specially mentioned the Heloderm, the only

known poisonous lizard in existence. A recent memoir

by Dr. Shufeldt {P.Z.S. 1890, p. 148) has supplied a good

NO. 1316, VOL. 5 l]

deal of information respecting the anatomy of this lizard.

The large poison glands are shown to lie on either side
of the lower jaw, their ducts opening into the floor of the
mouth, whence it is surmised that the poisonous secretion
finds its way along the grooved teeth of the mandible to
the inflicted wound. It is a curious fact that although
some of the teeth of the upper jaw of this Lizard are also
grooved, no trace of any poison gland has been found
here. An interesting account of the effects of the bite of
the Heloderm on the human subject has been already
recorded in our pages (X.^ture, vol. xxvii. p. 154), and

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it has been shown that its effects on man, though painful
at the time, are not of a serious nature.

One of the very few statements in this work with
which we are unable to agree, is to be found in the
account of the diving birds at the Zoo. With regard
to the Penguin, Mr. Cornish says : " It cannot lly in the
air ; it cannot walk, but hops as if its feet were lied
together ; it cannot even swim." If Mr. Cornish will
turn to the account of the expedition of the Dundee
whalers to the Ant.irctic Seas, given in the Scottish

2 7S

NATURE

[January 17, 1S95

Geographical Magazine for February IiJ94, he will find
the following passage : " On one occasion, in the north
of the Erebus-and-Terror Gulf, we saw large schools,
numbering 300 to 500, of the common black-throated
Penguin, swimming together ; the movements of each
school being controlled by a single individual of larger
size, which followed in the rear.'' It is quite possible
that this error may have arisen through the fact that, as
a rule, the Penguins, when allowed, in the Zoological
Gardens, to enter their tank, dive straight off the board
leading into the water, and remam under water until
all the fishes in the tank are caught and devoured. .After
that they usually betake themselves straight back to the
board. But that they can swim duck fashion, when they
wish to do so, admits of no doubt whatever.

The volume is illustrated by a series of Gambier
Bolton's photographs, which are certainly the best ever
taken of " Life at the Zoo.' Of these we are kindly
permitted to reproduce two. One of them represents
the Tiger " listening to soft music," and forms part of
a series made to illustrate " .Esthetics at the Zoo." The
other shows the Martial Hawk Eagle, a rather rare bird
from South .Africa. On the whole, we can cordially
recommend this volume for readers of the lighter litera-
ture of Natural History, and even as containing a certain
amount of novel information on " Life at the Zoo."

INTERCOLONIAL ASTRONOMY AND
METEOROLOGY.

WE learn from Mr. R. L. J. Ellery, F.R.S , that a
conference representing the three colonies of
New South Wales, South .Australia, and \'ictoria, met at '
the Observatory, Melbourne, on October 29. Mr. H. C. *
Russell, F.R.S. , from Sydney, and Sir Charles Todd,
F.R.S., from Adelaide, were present.

i\) As regards Australian standard time, it was
resolved to advise the respective Governments to
adopt for that purpose the time of the meridian of
150 E.

It was also agreed to advise that the changes from one
hour zone to another shall take place at the eastern and
western boundaries of the several colonies.

(2) A proposal, by Sir C. Todd, was adopted to the
eifect that the three observatories should co-operate in a
special series of observations for determination of co-
latitude, and for testing the applicability of the present
refraction tables to astronomical work at the various
observatories.

(3, It was resolved, at Mr. Russell's suggestion, to
carry out systematic cloud photography at each
observatory, as an aid to weather forecasting.

(4) As to agricultural forecasts, it was agreed to :
" That in each of the colonies represented a forecast of
;hc weather shall be sent to all the principal telegraph
stations each day, except Sunday (.Saturday's forecast
being for 48 hours), and that forms to contain a
week's forecasts be used, which it is proposed shall
be posted on a special board at the station receiving
forecasts."

(;) It was resolved that the storm signals to be used
be fhesame as used in England.

(6; On the suggestion of Mr. Russell, it was agreed
that further determination of the differences of longitude
of Adelaide, Melbourne, and Sydney, should be carried
out, and that periods when there was high atmospheric
pressure at one place, and low at another, be selected for
the operations, with the view of ascertaining if large
differences of atmospheric pressure between the eastern
and western stations had any influence on the longitude
results. Mr. Russell undertook to draw up a programme
for this undertaking.

NO 13 16, VOL. 51]

NOTES.
English geologists will be gratified to le.irn that the veteran
Prof. Preslwich has been elected a Vice-President of the
Geological Society of France. It is, we believe, the second time
only that this honour has been conferred on one who was not a
French subject. The Council of the Geological Society of
London has formally offered to Prof. Preslwich its congratula-
tions on the distinction thus received.

M. Mascart has succeeded M. Tisserand as President of the
Paris Societe d'Encouragement.

The death is announced of Prof. Karl v. Ilaushofer,
Director of the Technische Hochschule at Munich, and
Professor of Mineralogy in the University of that city.

Dr. G. M. Dawson-, C.M.G., F.R.S., has been appointed
Director of the Geographical Survey of Can.ida, in succession
to Dr. A. R. C. Selwyn, who has been superannuated.

We regret to note that the Duke of Argyll was attacked by
sudden indisposition while addressing a meeting at GLisgow on
Tuesday evening. His condition at first gave rise to serious
concern, and it was not till a late hour that he recovered
sufl'iciently to be conveyed to the residence of Lord Kelvin,
where he is staying.

.At Fishmongers' Hall, this evening, the Marquis of Lome
will present the prizes and certificates obtained by students in
connection with the City and Guilds of London Institute.

The twenty-second annual dinner of the old students of the
Royal School of Mines will be held on Friday, January 25, at
the Criterion Restaurant. A number of distinguished visitors
are expected to be present, and arrangements have been made
for a large gathering of associates and old students.

Thk annual meeting of the People's Palace Chemical Society
will be held on Thursday, January 24, when Dr. T. E. Thorpe,
F.R.S., will give an address on " Some causes and conditions
of chemical change." The chair will be taken by Prof.
Tilden at 8 p.m. Tickets may be obtained by ajiplicition to
the hon. sec, Mr. Thomas Yetton.

The Association for the Improvement of Geometrical
Teaching will hold a general meeting at University College,
Gowcr Street, next Saturday. In the morning, the report of
the council will be re.id, and the new oflicers will be proposed
for election. During the day, papers will be read on
"Algebra in Schools," "The Association's Syllabus of
Geometrical Conies," "The Conies of Apollonius," and
"Notes on Mensuration."

The forty-eighth annual general meeting of the Institution
of Mechanical Engineers will be held on Thursday evening,
January 31, and Friday evening, February I. The annual
report of the Council will then be presented, and the election
of the President, Vice-Presidents, and Members of Council will
lake place. The following papers will also be read and discussed,
as far as lime permits :— " The Determination of the Dryness of
Steam," by Prof. W. Cawlhornc Unwin, F.R.S.; "Com-
parison between Governing liy Throttling and by Variable
Expansion," by Captain H. Riall Sankey.

Thk freshwater biological station, which was established at
PIrrn three years .igo through the cfTorts of Dr. Olto Z.icharias,
seems to be assuming quite an internalion.il character. From a
recent report of the director, «c learn th.it nine investigators
worked at the station during the summer semester of last year,
and of these four were German, two English, two French, and
one Russian. Much interesting woik seems to have been.

JANUARY 17, 1895]

NATURE

279

accomplished, the results of which have been partially published
in the Forschtiit'^sbcrUhte of the station, while others are already
«n the press.

The death of Mr. Thomas Andrews at Guildford (says the
Times) removes one of the best-known and most successful pisci-
■culturisls of the day. His breeding ponds at Maslemere, on the
borders of Surrey and Hants, are perhaps, next to Sir James Mait-
land's famous establishment at Howietown, near Stirling, the
most important trout-rearing fishery in the kingdom. The series
of ponds are picturesquely situated on the side of a hill, and were
^11 planned under the immediate direction of the late owner,
who was a keen observer and an enthusiastic naturalist. They
aftbrded every facility for studying the various points in con-
nection with the artificial cultivation of trout. Mr. Andrews
h.id brought this particular branch of pisciculture (to which he
had devoted many years of his life) to a very high state of per-
fection. The distribution of ova and fiih from the Surrey ponds
was not merely confined to our home waters. At various times
consignments were despatched to foreign countries, Ceylon,
Buenos Ayres, Mauritius, and elsewhere. Mr. Andrews con-
tributed many important papers on fishery matters to various
peiiodicals.

The St. Petersburg Academy of Sciences has recently made
some changes in the system of publishing papers communicated
to it. In September 1894, it commenced the publication of
a monthly number, under the title Bulletin de V Acadenie Im-
fJriaU lies Sciencei, which serves as the organ of the three
classes of the Academy. This Bulletin i> intended to include
the proca-verbaux of the meetings, annual reports on scientific
researches, reports on prizes conferred by the Academy, notes
on the work of the museums, cStc. In addition to notices of this
kind, the Bulletin will contain short scientific papers. The
Af^ moires de V Acadhnie Imperiale des ScientLS will form in
future the second means of publication. It will be divided into
two independent series, dealing respectively with the physico-
malhematical section of the Academy's papers, and the his-
torical and philological section. The publication of the Melanges,
(iris du Bulletin, has been discontinued.

Some very low temperatures were reported to the Meteoro-
logical OlTice during the recent frost. At Braemar, in the east
of Scotland, the sheltered thermometer fell below zero on four
consecutive days, the lowest value being - 5° on the 9th
instant. At Hillington, in the east of England, the lowest
reading was z' on the 1 2th instant; in other districts the
cninima varied considerably, being 8° or 9' in the north of Scot-
land and the northeast and midland parts of England. This
severe weather came to a sudden termination on the night of
the izth-ljth instant, owing to the approach of a serious dis-
turbance from the Atlantic, which arrived off the Irish coast on
Saturday, and remained comparatively stationary during Sun-
day and Monday. Strong easterly gales were experienced on
the Scotch coasts, and very strong winds in other places. The
gale was accompanied by a very high sea on our north and east
coasts, and, as usual with easterly gales, many shipping
casualties occurred.

We learn from an article in Das Weller, that a permanent
meteorological station has been established by the Danish
authorities at Angmagsalik, on the east coast of Greenland
{Lat. 65' 37' N., Long. 37" i6' \V.), and has been provided with
self-recording instruments, in addition to the usual ones. This
station will be of much importance, as it forms a link between
those on the west coast of Greenland and the stations in Ice-
land, and as it is between Iceland and Greenland that the
centre of the Icelandic barometric low-pressure lies, the varying
position of which exercises a great influence on the weather

NO. I316, VOL. 51]

conditions of Europe. It is known, from a year's observations
made thereby Holm ten years ago, that the climate is very rough
and stormy ; during the year in question the mean temperature
was 5° below the freezing point, while the minimum reached
- 13° of Fahrenheit's scale. Meteorologists may well be
grateful to men who have undertaken to make observations in a
place where, in all probability, they will be cut ofT from all
other human intercourse for some years. Dr Nansen only
succeeded, after considerable difficulty, in reaching Lat. 63.^°
along this coast in the year iSSS.

It will be news to most people that dealers in drugs, both
wholesale and retail, cannot legally use kilogramme weights,
or any of the metric system of weights and measures, for the
export trade, though orders received from continental countries
are given in that system. A short draft Bill has been prepared
to amend the law, and will be presented to Parliament in the
coming session. The chief clause reads as follows : — " That,
on and alter the passing of this Act, wherever the word ' trade '
occurs in the Weights and Measures Acts of 187S and 1889, it
shall be so construed as not to prohibit or penalise the use of
metric weights and measures, verified by the Biard of Trade or
local authorities, by export traders." The Acts of 1876 and
1889 have been disregarded by many traders, but the London
County Council having recently intimated that they must
enforce the law, the passing of an amendment such as that pro-
posed has become necessary.

On Tuesday, January S, a paper was read before the Anthro-
pological Institute, on the Samoyad race, by Mr. Arthur
Montefiore. After dealing in some detail with the geographical
distribution of the various branches of the Samoyads, Mr,
Montefiore proceeded to give evidence of their affiiity with the
Finns, and, following Castre.T, placed them in the group which
that authority called Ural-.\ltaic. The evidence consisted
partly of physical measurements and cha.racteristics, partly of
similarity in ideas, habits and customs, and partly of identity
in language. It was shown in the course of the paper that the
language of the Samoyads is highly agglutinative and so inflec-
tional as to form a link, as it were, between the .Mongol and
Indo-Germanic groups. After dealing with the myths and con-
ceptions of deity held by this curious race, Mr. Montefiore read
a number of notes made by Mr. Frederick G. Jackson (the
leader of the Jackson- Harmsworth Polar expedition) during
his sojourn among the Samoyads in the autumn and winter of
■893-94, and his subsequent journey across the Great Tundra
between the Kara Sea and the Pechora River. Mr. Jackson's
notes were very full, and contained some remarkable evidence
of the completeness with which the Samoyad has adapted him-
self to the rigorous requirements of his environment. A number
of Samoyad implements and other articles (Including a highly
curious Samoyad doll and some calculating sticks) were exhibited,
together with a series of lantern slides from photographs, which
are necessarily new to English students of anthropology.

Does atmospheric dust exercise any perceptible influence on
the intensity of the sun's rays transmitted through it ? is the
question which Prof. A. Bartoli answers in the Nuovo Cimento.
He studied the effect of different thicknesses of air upon the
sun's heat by measuring the heating power of the sun at various
altitudes with the pyrheliometer, after the great eruption of Etna
in July 1892. On July 25, the air was filled with an impalpable
dust, which fell very gently, and gave to the sun a slight reddish
tinge. There were no clouds, and there was a dead calm. liy
comparing the absorptive influence of the air under these
conditions with that in a clear atmosphere. Prof. Uartoli found
that 28 per cent, of the heat transmitted by the pure air was
intercepted by the volcanic dust.

28o

NA TURE

[J AN LAKY i7, 1895

A FURTHER instalment of M. Raoul PiCtet's fascinating ex-
periments at very low temp:ratu-es is published in the Comptes
renJut. The object of the eicperiments was to test the power
of cotton-wool and other bad conductors to prevent the passage
of loT-temperature radiation. Copper cylinders were cooled
down to — 170° C. and packed in layers of cotton-wool of
various thicknesses. It was found that the cylinders rose to
about - So° very ripidly, and that the rate of warming was
the same whether the cylinders were naked or packed in cotton-
wool of 20 inches thick. The " bad conductor " behaved, in
fact, like a perfect conductor transparent to heat radiation.
Above - 80 the influence of the packing began to make itself
fell, the rn'e of warming varying with the thickness of the
layer.

Ix the current number of Statural Science, Captain Marshall-
Hall urges the importance of a fuller study of existing glaciers,
as the necessary bisis for any attempt at setting in order the
chaos of opinion on the nature and causes of the Glacial
period. He gives an ace mnt of the steps recently taken by
the .Alpine Club and the Glacier Committee of the International
Geological Congress towards drawing up a systematic statement
of the methods of observation, for the use of those who can
visit and examine modern glaciers in any part of the world.
For fuller details, readers are referred to papers in the Alpine
fournal (February 1S91, and November 1894) ; but a number
of subjects for careful observation are suggested, and some
necessary precautions mentioned. It is very satisfactory to see
that the members of the Alpine Club, if primarily climbers,
are able incidentally to do useful service to Geology.

In the last number of tlie Records of the Geological Survey
of India, Dr. Noetling announces an interesting discovery from
Baluchistan. Certain beds which Mr. Oldham had recently
described as in'ermediate betwieci Cretaceous and T,erliary he
finds really belong to th • Danian — a stage to which the English
chalk nowhere reaches (except perhaps in Norfolk), but which
forms the summit of the Cretaceous in various parts of Europe.
In examining the Echinoids from the Biluchisl.in beds. Dr.
N>etling found a striking resemblance to those fr)m the Danian
beds in the Pyrenees. That the Pyrenein fauna should resenble
that of such a distant region more than the nearer ones of
Northern Europe, is another of th;many pieces of evidence of
ancient life-provinces — not improbably climatic in this case —
that accumulate as geological research is extended into distant
parts of the world. It must be coupled with the further fact
that the Baluchistan Echinoids have little in common with those
of the same age in Southern India.

The last number of the Comptes rendut contains a paper by
R. Colson, on the conditions which have to be fulfilled in order
to obtain correct results when measuring liquid resistances with
alternating currents and a telephone. Tne author, while work-
ing on the propagation of electrical waves of slow period,
obtained results which have an important bearing on the above
method of measuring liquid resistances. The results obtained
depend on the suppoiition thai, even in the case of alternating
currents in liquid resistances, Ohm's law holds. However, this
la V does not hold good in the case of the propagation of waves
of high potential, such as are furnished by the secondary of an
induction coil in high resistances, such as threads saturated with
a solution of calcium chloride, or capillary tubes filled with
water. The author gives a series of tests which, when applied
to any given arrangement of conductors, will show whether the
above cfTecls will have any influence on the result.

Mk. B. D. Peirce has contributed a paper to the American
f'Urnal of Science (vo\. xlviii. p. 312), on the thermo-electric
properties of platinoid and manganine. Since plitiaoid and
NO 1316 VOL. 51]

manganine wires are often used in potentiometers and slide
wire Wheatstone's Bridges, the thermo-electric properties of
these metals are of considerable interest. The author has
primarily determined the electromotive force of the above
metals and copper, since this is the most interesting case from
a practical point of view. He finds that after the manganine
wire has been well annealed, the thermo-electric phenomena
are quite regular. While the mean electromotive force for a
difTerence of 10° C. between the hot and cold junctions of a
copper manganine couple is about 55 microvolts, in the case
of a platinoid-copper couple the mean electromotive force for
the same difference of temperature is about 170 microvolts.
Incidentally the author has examined the thermo-electromotive
force of couples consisting of different samples of commeicial
copper, and he finds that two specimens of annealed copper
wire bought from different makers hardly ever yielded more
than one or two C.G.S. units of E.M.F. per degree Centigrade.

-A FEW particulars concerning the earthquake felt in Nicar.igua
and Honduras in November 1S94, have been sent to us from
Managua, by Mr. J. Crawford. Shocks were felt for twenty
seconds at Managua, about gh. 36,n., and another series,
lasting about thirty seconds, at eleven in the evening of
November 19. Mr. Ciawford h.as been able to trace the course
of the waves for about 1 20 miles to the north-west and south-
east of the city. At Managua, the undulations were short and
rapid ; they were stronger at the city of Malaya — twelve miles
to the eastward, and still stronger at Granada — about twenty-
four miles east Aard. In the latter place, houses were thrown
down by the vibrations, and also at Chinandega — seventy
miles west of Managua, though at Managua itself the shocks
were not of sufficient severity to fracture any of the walls of
the houses, or displace any of the tiles on the roofs. It is
remarkable that the earthquakes were most violent both east
and west of the city.

Mr. I. C. Shensto.ne has taken a census of remarkable oak
trees in Essex, and he gives, in the Essex Nattirjlist, de-
scriptions and illustrations of noteworthy specimens found by
him ; together with notes on a few oak trees outside the county
The five tiees with the largest trunks in Great Britain, stated in
"Loudon's Arboretum," are: Cowthorpe Oak, Yorkshire,
78 feet ; Merton Oak, Norfolk, 63 feet ; Hempstead Oak,
Essex, 53 feet ; Grimstone Oak, Surrey, 48 feet ; Salsey Oak,
Norlhampton, 46 feet. Among trees having the widest stretch
of boughs, are the Worksop Oak, 180 feet : and the Oakley Oak,
1 10 feet. All these trees are not, however, standing at the
present time. The Hempstead Oak fell about twenty-five
years a^o, and a mutilated and decayed tru ik is all that remains
of this forest giant. A fine tree, thirty-one feet in circumference,
exists in the park at D.inbury Palace. Tne inside of the bole
was completely burnt out more than sixty years ago, but the
tree has continued to grow, an I will probably yet survive many
years. Several of the trees mentioned arc said to be from five
hundred to a Ih msand years old, but there is not sufficient
evidence to decide the point at all accurately.

British ornithologists have long been aware that the in-
crease and extension of r.inge of the starling presents some
interesting and phenomenal facts. They will therefore follow
with interest a paper on the increase and dislriliution of the
bird in .Scotland, contributed by Mr. J. A. Haivie-Brown to
the Annats of ScollisU Natural History for January. By look-
ing up old records dating back to the end of last century, and
by collecting information through a special circular, it has been
possible to give a consecutive statement of the steps of advance.
The account, and the m.ip accompanying it, show that, as re-
gards Scotland, the starling is almost omnipresent. The statistics

January 17, 1895]

NA TURE

2S1

indicate " that two great centres of habitation have influenced
the dispersal of the species : an earlier one in the Shetland-;,
Orkney, and the Outer Hebrides, and north coasts and
north-east of Caithness, from north-east towards south-west ;
and a later one, entering Scotland in the south and passing
north through the south and central districts of Scotland.
Moray appears to have drawn its supplies from the northward,
in comparatively recent years ; but the districts to the south of
the Grampians mostly, if not entirely, from the southwards.
... It might not, perhaps, be too rash to predict that the
day may yet arrive when the starling having increased still
more prodigiously, and every crevice and cranny having be-
come populated by these cosmopolites, a great struggle for
existence even amongst themselves may become necessary to
preserve the balance of nature. Before this can take place,
however, the probability exists that some other weaker species
may have to go to the wall. Indeed, there are already indica-
tions of such a fact in at least one instance and locality — by
sheer force of numbers."

In the eighth annual report of the Liverpool Marine Biology
Committee, edited by Prof. Herdman, there is an interesting
account of the work carried on during the past year at the
biological station at Port Erin. A number of important addi-
tions to the fauna already known in that neighbourhood are
recorded, including Dicorync ctmfcrta, Crisia ramota, Amphi-
codoii fritillaria, and some forms of Copepoda new to science,
Pseiidocyclopia stephoiJes and several species of the genus
Ectiiiosonta. Many observations have been made on the sub-
marine deposits of the Irish Sea, and a preliminary general
account is given in the report. The bottom, down to the
depth of 10 fathoms, is chiefly covered with sand ; at a greater
depth, between lo and 20 fathoms, there is a large admixture
of mud ; from 20 to 50 fathoms the bottom deposits are greatly
varied, and here the richest fauna occurs ; below 50 fathom i is
found a bluish-grey tenacious mud, with a peculiar and charac-
teristic fauna. Prof. Herdman very justly points out the im-
portance of a thorough investigation of the submarine deposits
round our coast ; he regards the nature of these deposits as
probably the most important of the various factors that deter-
mine the distribution of animals over the sea-bottom within
one zoological area. " In practically the same water, identical
in temperature, salinity, and transparency, at the same depth,
with, so far as one can see, all the other surrounding conditions
the same, the fauna varies from place to place with changes in
the bottom — mud, sand, nullipores, and shell-beds, all have their
characteristic assemblages of animals." The concluding part
of the report contains a short account of a plan for the distri-
bution of drift-bottles in order to obtain information with
regard to the currents in the Irish Sea which afl'ect small float-
ing bodies ; this experiment is based upon the plan employed
by Prince Monaco in the Atlantic a few years ago. The
observations made on the course of the drift-bottles up to the
present have already been described in our columns by Prof.
Herdman (Nature, December 13, 1894, p. 151).

With the January Journal of the Chemical Society, we have
received a supplementary number, containing title-pages, con-
tents, and indexes of volumes Ixv. and Ixvi. (parts i. and ii.)
of the Journal.

The resolutions accepted by the International Congress of
Hygiene and Demography, held at Budapest in September
last, have just been published in the form of a pamphlet. They
are printed in four languages — Hungarian, French, German, and
English.

Thi-; first part of a new catalogue of entomological works
offered for sale, has been issued by R. Friedlander and Son,

NO. I316, VOL. -^l]

Berlin. The list, which is No. 416 of the " Biicher-Verzeich-
niss," published by Friedlander, is devotel to fossil insects, Co-
leoptera, and miscellaneous works on entomology.

We regret to announce that, owing to the death of Father
Denza, the publication of the BolUlihio Mfiisuale, issued by
the Moncalieri Observatory for the last fourteen years, is to be
discontinued, and that the Italian Meteorological Society is to
be dissolved. We hope that some other pioneer of Italian
meteorology will take up the good work left by Father Denza.

The publication of " The Cambridge Natural History " will
shortly be commenced by Messrs. Macmillan and Co. The
first volume to appear will co itain '• Molluscs," by the Rev. A.
II. Cooke; " Brachiopods (Recent)," by Mr. A. E. Shipley;
and " Brachiopods (Fossil)," by Mr. F. R. C. Reed. This will
be followed, in the course of a few months, by two other
volumes in the same series, on " Insects," by Dr. David Sharp,
F. R.S. The whole series, which will include ten volumes,
fully illustrated, is intended, in the first instance, for those who
have not had any special scientific training ; but an attempt will
be made to combine popular treatment and popular language
with the most modern results of scientific research.

Referring to the announcement that ten Surinam water-
toads had been received at the Zoological Society's Gardens
(Naiure, p. 85), Dr. C. Kerbert, the Director of the
Koninklijk Zov>!ogisch Genootschap, informs us that a number
of these interesting animals were received at -Amsterdam in
October 1893, and are still living.

The Royal Horticultural Society has been established for
ninety years, and there are at present three thousand Fellows on
its roll. It works in various ways " for the improvement of
horticulture ir all its branches, ornamental as well as useful."
The Jourital of the Society usually contains much valuable
information on scientific and practical gardening. In the
January issue, there are a number of papers read at a conference
on trees, and others read at a conference on British-grown fruit.
Perhaps the most important section of the Society is the strong
Scientific Committee appointed to examine and report upon
instances, submitted by the Fellows, of diseases and injuries of
plants, caused by insects or otherwise. The Committee give
their advice on all matters connected with the prevention or cure
of disease, and are glad to receive specimens of malformation,
or other subjects of horticultural or botanical interest.

A DEi-"lNrriv and trustworthy answer appears at last to be
given to the long-standing question of the closely approximating
atomic weights of nickel and cobalt, in a communication from
Prof. Winkler to the Zeitschrifl fiir Ano)ganisc/u Chemie. The
great difficulty in deciding the actual values of the atomic con-
stants of these interesting metals has been largely owing to the
f.xct that the methods of analysis hitherto adopted have not been
free from all source of error. During the last few years, how-
ever, very considerable progress has been made in the chemistry
of the compounds of nickel and cobalt, and the sources of error
are now more correctly appreciated, and consequently more
amenable to elimination. It is inconceivable, in the light of the
ample verification which the periodic generalisation associ.ited
with the names of Newlanjs and .Mendelceft" has received since
its inception, by the subsequent accumulation of cvperimental
facts, that the atoms of nickel and cobalt can both be endowed
with the same relative weight, as was for so long supposed to be
the case. A short time .ago. Prof. Winkler carried out a series
of analyses of the chlorides, prepared from the electrolytically
deposited metals, and obtained the numbers Ni = sS'go and
Co = 5967. Having, however, still some doubts as to the
absolute accuracy of the decimal places, owing to the possibility
of a minute source of error in the preparation of pure neutral

2S2

NA TURE

[January 17, 1S95

chlorides, another series of experimenls hive been carried out
by a method which Prof. Winkler states is in his opinion
(and there can be none higher as regards work with the
two metals in question) quite unimpeachable. The older
methods based upon the electrolytic determination of
the metals were found to lead to an error in the
case of cobalt, owin» to the fact that a smill quantity of the
hydrated oxide Co.03-2H .0 is contained in the deposit upon
the platinum electrode, while in the case of nickel no oxidation
whatever occurs. This discovery was consequent upon another,
na-nely, that a solution of iidine in potassium iodide of deci-
normal strength is capable of instantly dissolving the deposited
metal from the platinum terminal without in the slightest
attac'<ing the latter, producing a solution of the iodide of the
metal. In the case of nickel the platinum is left perfectly
clean, while deposited cobalt invariably leaves a stain due to
about half per cent, of oxide. The electrolyticilly-deposited
cobal; employed by Prof. Winkler was therefore all reduced in
pure hydrogen before use ; when subs:queatly dissolved in the
iodine solution, no trace of oxide was ever left. The method
of analysis consisted in determining, by titration with pure
sodium thiosulphaie, the excess of iodine left after solution of
the pure metals to form the iodides. Two complete series of
analyses, each consisting of a considerable number of indi-
vidual determination-, were carried out with an interval of some
months, in order to employ metals from totally independent
mineral deposits. The results are most concordant, and lead
to the final numbers, Xi = 58-2 and Co = 5937, when H = i
and I = 1 26 53. The atomic weight of cobalt must therefore
be accepted as at least half a unit higher than that of nickel, a
result likewise in accordance with the work of Prof. Winkler
published a short time ago.

OUR ASTRONOMICAL COLUMN.

5 CeI'HEI. — Further particulars of Dr. Belopolsky's spectro-
scopic study of this variable s'ar (N.^TtKE, November I, 1894,
p. 21) are given in the BulUlin of the Si. Petersburg .V.-ademy
of Sciences, November, 1S94, and some of his numerical results
are slightly changed. He has shown for the first time that
orbital movement is as closely associated with this class of
short-period variable stars as with those of the Algol class, in
which the minima are produced by eclipses. Alihough the
spectrum of 8 Cephci is described as of Vogel's Class 11. (j, it is
pointed out that it differs fr.im that of the sun in many respects,
some of the lines which are narrow and feeble in the sun being
strong in the slar, and vi<e versa. There does not appear to be
any change in the character of the spectrum, other than a varia-
tion of intensity, as the light of the slar changes.

The displacements of the lines with respect to the comparison
spectra of iron and hydrogen indicate that the slar has an
'.r'ji'.il movement in a period corresponding to that of the
li.;h- changes '5. 1, oh.), and that th-; eccentricity of the orbit is
o 514. The form ol the curve of velocities which is given, indi-
cates that the major axis of the orbit must be very nearly
directed towards the earth, and the system is approaching the
ca'th with a velocity of about 12 linglish miles per second.
With reference \n the centre of movement, Ihe maximum
\ and recession are about 13 English miles

\ receding for about a day after minimum,

3 day.s more, and receding until mini-
ron is the point of the orbit farthest
I IS passed about a day after minimum.

I ne apparent .semi axis major is about 8l8,8co English
mile<, so that the whole oibil is less than twice the sun's dia-
meter. We are not aware that any attempt has been made to
determine Ihe parallax of the star, but unless it has a very high
emissive power, its small size would indicate that it must be
relatively near to us.

.Notwithstanding thot Ihe lime of a possible eclipse is a day
after Ihe minimum of the light curve, iJr. HclopoUky scemsto be
of opinion thai the variation may he due to eclipsing, lie
app<ar« to believe that further work may show that there is
some systematic error, and that peiiastron may really coincide

NO. 1316, VOL. S']

wilh the minimum. As the light changes appear to be going
on continuously throughout the period, it is clear that the
eclipsmg cannot be of the simple kind wilh which we are
familiar in the case of Algol.

The V.\tic.^n Observatory. — K day after the death of
Father Denza, we received the fourth volume of the " Pubbli-
cazioni della Specola Vaticana." Every annual report of the
work done at the Vatican Observatory is more voluminous than
the one preceding it. The volume which came to us last month,
and to which Father Denza's death gives a melancholy interest,
runs into more than six hundred pages, and is illustrated by
forty-two plates. .-Vmong these are illustrations of Ihe Dumb-
bell nebula in Vulpecula, the Pleiades nebula, the Orion nebula
after exposures of thirty minutes and of nine hours, two photo-
graphs of the eclipse of .April 1S93, a photograph of the sun
with the big spot of August 1S93, together with two enlarged
pictures of the spot, and a map showing the direction of motion
of the meteors observed on August lo-li of the same year.
Papers on the subjects of the illustrations make up the greater
part of the astronomical section of the report. Altogether, ten
photographs were taken at Rome during the eclipse of April
1S93, and contact observations were also made. The numerous
meteorobservations made under Father Uenza'sdirection in Italy,
in August and November 1 89;, are catalogued and commented
upon. It is to be hoped that the system of meteor-observation
which the late Director instituted will not be allowed to lapse.
In celestial photography we note that in addition to the work
for the photographic chart and catalogue, 248 photographs were
taken of various cele-tial objects, 150 being photographs ol the
sun. Hut the astronomical results by no means represent the
total work carried out at Ihe observatory. .Meteorology and
terrestrial phisics come in for a large share of attention. To
us it seems that the only thing wanting to make the Vatican
Observatory a true astro-physical observatory is a section for
spectroscopic investigations.

Many astronomers will be interested to know that a full and
appreciative notice if Father Denza's life and work has been
written by P. Armani, of the Collegio dei S.S. Biagio e Carlo.
Another full notice appeared in Comios of December 22.

An iNmsPENSAiiLE .Annl'aire. — This year is the centenary
of the creation of the Bureau des Longitudes, the invaluable
Aii'iuairc of which has been received for 1S95. It is quite un-
necessary to remind astronomers of the merits of this veritable
: ade III c<:ii III , for they know its usefulness better perhaps than
workers in the other branches of physical science to which it
appeals. .-V few changes have been made since the previous
issue. M. Berthelot has completely revised and corrected the
tables relating to thermo-chemislry. M. Moureaux has in-
serted in the tables of the magnetic elements in France, the
values determined directly by him in 1894, at nearly six
hundred places. Prof. (ILasenapp has added five new stars to
his table of the elements of the orbits of double stars. The list
of comets has been brought up to Ihe end of 1893, and that of
minor planets up to November 1894. There are live articles in
the volume, the subjects and authors being : Lunar atmospheric
waves, by M. Bouquet de la Grye ; the Geodetic Congress at
Innsbruck, by M. Tisserand ; the Observatory on Mont Blanc,
by M. janssen ; photographic photometry, by the same author;
and a report on the proposition to unify the .astronomical and
civil days, by M. Poincarc (see the next note).

TllK U.S'II-ICATION 01-- Civil, ANII ASTRO.VOMICAI. DAYS.—
It will be remembered that in 1893, the Astronomical and
Physical Society of Toronto invited replies from astronomers to
the question : " Is it desirable, all interests considered, that
on and after the first day of January 1901, the Astronomical
Hay should everywhere begin at moan midnight ?" Theresull
of the voting was noted in Nature, April 5, 1894, p. 542;
and to this may now be added the following resolution adopted
by the IJureau des Longitudes upon the <|ucstion (Aniiiiaire (or
1895): — "The Bureau des Longitudes is lavourable, in prin-
ciple, to the reform proposed by the Canadian Institute to
change the time from which to reckon the astronomical day.
The Bureau thinks that this reform, as has been observed by
the Lords of the .\dmiraliy, will be of little avail unless an
undcistanding is come to between tlic Governments publishing
the principal ephcmerides. Finally, considering that the
unification will not really be complete until the civil hour is
reckoned from o to 24 hours, as is Ihe case in Italy, the Bureau
is of the opinion that this reform ought to be realised as soon as
possible."

January 17, 1895]

NATURE

28-

THE FOUNDATIONS OF DYNAMICS}

''pniS posthumous volume of Hertz's works, edited by Prof.
^ Lenard, with a preface by von Helmholtz, has a doubly
melancholy interest. It is the last work of Hertz upon which
he was engaged until a few days before his death, and it con-
tains a preface which is almost the last work of von Helmholtz.
The pupil died shortly before his master, and by the departure
of such a pupil and of such a master, science, and with science
mankind, have lost many prospects of advances in the near
future.

In his preface, von Helmholtz pays a touching tribute to the
genius of his favourite pupil, from whom he hoped most, and
who had drunk most deeply of his master's thoughts. In 1878
their intimacy began. At that lime difficulties connected with
various electrical theories of action at a distance were occupying
his thoughts, and he offered a prize for the best essay on in-
duction in non-induclively wound coils. Weber's theory would
have involved an inertia of the electric current di>iinct from
the magnetic inertia. The question is still interesting in con-
nection wiih discharges between two charged conductors, one
of which completely surrounds the other when a dielectric be-
tween them is suddenly made conductive. There is then no
magnetic force. Is there no inertia ? Can a medium become
jKt/cr't'w/)' conducting ? Is a conducting medium homogeneous?
Is there inertia 01 ionic charges which represent the non-homo-
geneiiy of the medium ? These questions still refjuire answer-
ing ; but in the seventies, in Germany, Maxwell'.* idea of mag-
netic force accompanying displacement currents was not
generally received, and Helmhollz's question as to the in-
duction in non-inductively wound coils really had reference to
these displacements. Hertz won the prize by showing that at
most only i 20th or i/3oth of the extra-current could be due to
electric inertia. By subsequent experiments on the possible
effect of centrifugal force on the current in rapidly rotating
plate=, he reduced this estimate to a very much smaller value.
Mr. Larmor has suggested that any centrifugal force may be
balanced by a tension in the length of the current, much in the
same way that the tension of a running rope will balance centri-
fugal force in the curves round which it may be running. In
every way the subject deserves further investigation, for it is
intimately connected with the most funlamenial questions as to
the nature of electricity and its connection with maiter.

The next thing to which Hertz devoted himself was a prize
problem proposed, at von Helmhollz's suggestion, by the
Berlin Academy. The problem was to investigate .Mixwell's
postulate that changing electric displacement was an electric
current. This was the bud from which Herizs great work
sprang. Of it von Helmholtz says : " It is a pity we do not
possess more such histories of the inner psychological develop-
ment of knowledge. Its author deserves our sincerest thanks
for letting us see so deeply into the inmost working of his
thoughts, and for recording even his temporary mistakes. By
this work Hertz has settled for ever the question as to electro-
magnetic actions being propagated by a medium, and the only
outstanding question of the kind is as to gravitation, which we
do not yet know how to logically explain as other than a pure
action at a distance.' It thus appears that von Helmholtz to
the last was unconvinced as to the probahility of any hypothesis
like Le Sage's or Osborne Reynolds's. He seems, on the other
hand, to have been satisfied with the possibility of chemical
actions being explained cither by electromagnetic actions or by
actions not at a distance. This latter term, of course, requires
explanation as to what " al a distance " means. .\ny actions
other than those of absolutely rigid bodies, such, for instance,
as the fairly well-established forces of attraction of gaseous
molecules lor one another, and some of which can hardly be
explained either by electricity, magnetism, or gravitation, seem
to be actions at a distance that require explanation just as much
as gravitation.

Following this short history of the work of his pupil which,
coming from such a master, must have a permanent interest to
all, von Helmholtz gives a. lisumt' oi the last work of Herlz. In
it there is attempted a continuously elabirated presentation of
a complete and self-dependent system of mechanics, in which
each particular applicali )n of this science is deduced from a
single fundamental law which can of course be itself only
assumed as a plausible hypothesis. In order to ex,)lain how

1 'The Principles of Dvn.Tnics developed on ncv lines: — Hertz's Col-
lected Works," vol. iii. Pp. 310. (Leipzig : B.irth, 1594.)

NO. 1316, VOL. 5 l]

this is required, von Helmholtz gives a short history of ihe
development of ihe science of mechanics. The first develop-
ments arose from the study of the equilibrium and motion of
solid bodies ;n direct contacts with one another, such as the
simple machines, the lever, the inclined plane, the pulley.
The law of virtual velocities gives the most fundamental general
solution of all such problems. Galileo subsequently developed
Ihe knowledge of inertia and of moving force as an accelerating
agent. It was, however, conceived by him as a succession of
blows. Newton was the first who arrived at the notion of force
acting at a distance, and its more accurate determination by the
principle of action and reaction. It is well known how
strenuously he and his contemporaries resisted this idea of pure
action at a distance. From this men developed the methods
of treating all problems of conservation forces with constant
connections whose most general solution is given by
DAlembert's principle. All the general principles of dynamics
have been developed from Newton's hypothesis of permanent
forces between material points and permanent connections be-
tween them. It was subsequently found that these laws held
even when these foundations could not be proved, and it was
thence deduced that all the laws of nature agreed with certain
general characteristics ol Newton's conservative forces of attrac-
tion, although it was not found possible to deduce all these
generalisations Irom one common fundamental principle. Hertz
has devoted himself to discovering such a fundamental principle
for mechanics, from which all the laws of mechanics hitherto
known as universally valid can be deduced ; and he has carried
out this with great acuteness, and by means of a very remark-
able presentation of a peculiarly general kinematic conception.
In working it out, he returns to the oldest mechanical theories,
and supposes all actions to be by means of rigid connections.
Of course he has to assume that there are innumerable imper-
ceptible masses and invisible motions of these, in order to ex-
plain the apparent actions upon one another of bodies that are
not in immediate contact. 'I'hough he has not given examples
of how this may be the case, he evidently builds his expectation
of being thus able to explain natural aclions upon the existence
of cyclical systems, rollers, &c., with invisible motions. The
justification of such an assumption can only be obtained by its
success. Von Helmholtz concludes this interesting preface by
remarking how English physicists have so often based their
work on dynamical and geometrical suppositions, as for ex-
ample Lord Kelvin and his vortex atoms. Maxwell and his cells
with rotating contents. These physicists, he says, "have
clearly been more satisfactorily helped by such illustrations,
than by the mere most general representations of the facts and
their laws as given by the system of physical differential
equations. I must confess that I have restricied myself to
this latter method of investigation, and have felt most con-
fidence therein ; and indeed I might not have arrived at any
important results by the methods which eminent physicists such
as the three mentioned have employed."

Although so far it seems as if ihere were very little to choose
between the old methods of supposing that natural aclions can
be explained by conservative forces between molecules and by
s>stems of rigid connections, Hertz in bis introduction shows
that he is dissatisfied with the hypotheses, of these forces as
entities, while von Helmholtz, by his silence, seems to hold the
view that the old method was good enough for him. Hertz's
method has, however, the advantage of turning our attention
to something definite to be investigated and invented, namely,
the structure of these rigid connections It is apparently very
closely related to Osborne Reynolds's and " Waterdalc's, " sug-
gestions as to the structure of the ether, namely, that it consists
of perfectly rigid particles in almost complete juxtaposition
which, whether by their smoothness or by their rolling upon one
another, waste no energy in internal heat motions.

In his own preface, Ileriz says that he has culled many
things from many minds, nothing particular in his work is new ;
what he presents as new is the arrangement and collocation of
the whole, and the logical, or rather philosophical, aspect
thereby attained.

To these prefaces Ihere follows a long introduction, in which
Heilz reviews and criticises the present foundations of dynamics.
The great road by which this domain is now entered is one that
was laid by .\rchimedes, Galileo, Newton, and Lagrange. It is
founded on our notions of space, time, force, and mass. F'orce
is introduced prior to mot.ion, as the independent cause thereof.
Galileo's notion of inertia only involved space, time, and mass.

284

NATURE

[January 17, 1895

Newton first introduced all four notions. To this D'Alembert's
principle gave the analytical method of treating generally con-
nected systems. Beyond it all is deduction. Here Hertz in-
troduces a discu-ision as to the so-called forces of inerlia. From
his discussing the case of a solid subject to centripetal acceler-
ation by means of a strinj, the question is much more intricate
than if he had taken the case of a body falling freely under
gravity, where the force is applied directly by the earth to each
point of the body, and not, as in the caseof thestring.distributed
to each part by stresses in the solid. Hertz seems to consider
that there is some outstanding confusion in applying the prin-
ciple of equality of action and reaction, and appears to hold that
by this principle the action on the body requires some reaction
in the- body whose acceleration is the effect of the force. He
dies not seem fully to appreciate that action and reaction are
always on different bodies. From his consideration of this, and
fnm a general review of our conception of force, he concludes
that there is something mysterious about it, that its nature is a
problem in physics, like the nature of electricity. We have a
quite distinct conception of velocity : why not of force? He
concludes that the mystery is not due to our not having enough
ideas to associate with the word, but to our trying to put too
much into it. These mysteries, however, do not invalidate in
any way the deductions that have been made ; they only require
lis to set k out a new foundation for our dynamics. He goes on
' 1 criticise this method of filling nature with forces of which,
• eing ultimately between molecules, we can have no direct ex-
perience K piece of iron on a table is acted on by gravitation,
ohesion, repulsion, magnetic, electromagnetic, electric, and
chemical forces. Some of these would drag it to pieces if un-

alanced to a nicety by others. Is this a sound view of nature?
I Jan we not get some more attractive one?
A second view may be elaborated by making our fundamental

uantities, space, time, mass, and energy. There is no book
in which this view of nature is fully and consistently worked
out, at least none that Hertz was acquainted with. He sketches
how it might proceed. Besides the postulate of the conserva-
tion of energy we require some definition of potential energy
and experimental relations connecting it with space, and in
addition we have a choice of relations with kinetic energy, of
which Hertz suggests the choice of the integral form of Hamil-
ton's principle known as that of least action. This is, no doubt,
a recondite idea to use as a fundamental postulate, but it only
implicitly involves the idea of force, which then comes in
merely as a definition. To this method, which certainly has
several great advantages, Heriz makes a number of olijeclions.
In the first place he objects that it requires the equations of
connection to be integral equations, and we know such actions
as pure rolling of one hard body on another cannot be so ex-
pressed. \Ve must, in order to specify the subsequent motion,
know the rate of rotation round the normal axis through the
point of contact, and this cannot be specified except in terms of
fliflereniials. To such motions we cannot apply the i)roposed
prinriple of lea^t action, and yet we can hardly dispute that
such rolling is possible in nature. If we treat it as the limits of
frictional sliding, we introduce the whole of the difficulties of
force, or of the irregular heat actions which have not yet been
fully made amenable to accurate dynamical treatment, .\gain,
difficulties arise as to the foundation of this method. There is
great difficulty in specifying energy itself. Hnwcan it be satis-
factorily measured without returning to the first method, and
introducing the i<lca of force? .Some have conceived of energy
as a sort of substance ; but when we try to form concrete con-
ceptions of what is occurring, we get involved in perplexities.
The very existence of two forms of energy is a very serious
difficulty. Again, it is doubtful whether it can be sound to
consider the integral of lea.si action as a/««a'<3w<r»n'a/ principle.
It makes the present depend on the future. It sets the problem
to nature to make a certain Integral the minimum.

A good many of Iheseobjections could begot over by making
all energy kinetic, which is what Hertz himself practically
assumes in his own method.

This third method begins by auuming only three fundamental
quantities, time, space, and mass, and puis aside as non-funda-
mental, force and cncrijy. in order to explain how nature
works, we already do postulate invisible umlcrlying structures
in nature. We postulate these in (he atoms and molecules of
matter. Hertz sees in all actions the working of an underlying
structure whose masses and motions are producing the effects
on matter that we perceive, and what we call force and energy

NO. I 3 16, VOL. 51]

are due to the actions of these invisible structures, which he
implicitly identifies with the ether.

We must, however, assume certain connections between the
three quantities, time, space, and mass. Between time and mass
there is no direct connection. Space and mass. Hertz con-
siders, are connected by the existence of a given miiss at each
point of space. He cannot mean here to assume a complete
plenum, which would make serious difficulties in the way of
the working of what he subsequently assumes to be a structure
of rigid bodies ; he must include a vanishingly small density at
some points, though perhaps he may have had in view the
filling of the interstices between his rigid bodies with a fluid.
Any way, he goes on to say that some connection is required
between all three quantities, and for this purpose he postulates
his great fundamental single law of motion, which he considers
is an extension to systems of Newton's first law of motion
for a single body ; it is that a system, which is unconnected
with any others, moves with constant swiftness along one of its
straightest paths. " Systema omne liberum perseverare in
statu quo quiescendi vel movendi uniformiter in directissimam."
In order to understand what Hertz here means by the path of
a system, and by its being straight or curved, requires further
explanation ; but from this principle, which is capable of
analytical representation, and from the assumption that the
connections of a sj'Stem are all rigid, he deduces all the funda-
mental principles, conservation of areas, momenium, energy,
least action, &c. In considering the motion of any part of a
system, we find that we may conveniently introduce certain
actions of the oilier parts of the system upon it which are
measured by forces, which thus come in as mere definitions.
He does not seem to inveslig.ite anywhere the question as to
the danger of his rigid connections becoming tangled.
Analytically a postulate that the points of two different bodies
that act on one another are in contact is easily expressed, but it
does not follow that when we come to invent actual rigid
connections to produce the observed effects, they will do so for
any length of time wiihout jamming. It is a seductive theory
that gravitation or electrical actions may be due to vortex
filaments ending on atoms ; but the tangling of the filaments is
a very serious diflSculty that has not been satisfactorily
got over. HerIz does not seem to feel Ihis as a serious
difficulty, but he does notice an obvious objection that is
sure to be raised, namely, that rigidity in ilself postuKates
forces. To this he replies that rigidity in itself is merely a
matter of definition and of fact. How is our view of the fact
that two points are at a constant distance apart, improved by
saying that there is a force between them ? As, however, real
bodies are only imperfectly rigid. Hertz concedes that it may
be that when we learn more about these invisible connections,
they may turn out not to be absolutely rigid. It is a matter for
further investigation. This very same view might have been
urged, and has been urged already with reference to actions
like gravity. The law of gravity can be perfectly well de-
scribed without any reference to the notion of force. We may
say, every clement of matter moves towards every other ele-
ment in the universe with an acceleration inversely pro-
portional to the square of their distances apart. We can
describe the law kinetically, just as Ileriz proposes to describe
the law of motion of parts of a rigid body. There is no
iicesiily, however convenient it may be, to introduce the notion
of force ; the other bodies in the universe .are a sufficient cause
for motion of each, without postulating an entity, force. The
principal reason for introducing this notion was to account for
a body acting where it was not ; force was invented to get
over this ; the body produced force, and this force existed where
the body did not, and there acted on other bodies. This whole
difficulty seems, however, to be partly due to want of distinct
ideas connected with the question of where a boily is. We are
so accustomed to consider a body as having a definite bound.ary,
that we think there is a definite boundary in reality. All we
know of the atoms and molecules, however, would lead us to
conclude Ih.at round the centre of e.ich there is a very com-
plexly structured region which may or may not change
abruptly in structure, but which often extends to con-
siderable distances from the atom, so that it is practically
impossible to stale absolutely where the atom ends and where
the empty space begins. With this view of matter there is
no serious reason why we may not rightly consider each atom
as existing everywhere that it acts, that is, throughout the
whole of space, for its action in causing gravitional .accelera-

January 17, 1895J

NATURE

28 =

tions exists, so far as we know, throughout space. A view of
this kind entirely gets over any difficulty of a body acting where
it is not ; for all bodies arc everywhere, and if we consider
matter to be the cause of motion of other matter, there seem;
no very imperious necessity for imagining another cause which
we call force.

There are two assumptions that Hertz makes which he con-
siders can only be proved by their success. One is that all the
connections in nature can he represented by linear difterenlial
equations. There are plenty of cases imaginable in which
this would not be true, as, for example, connections depending
on the curvature of the path. The other assumption is that
forces can be represented by force functions. This, again, may
not be a complete representation of nature.

Following this introduction comes the book itself, which is
divided into two parts. The first part is purely kinemalical,
the second deals with the deductions from Hertz's fundamental
postulate of motion in the straightest possible path.

The first part begins by explaining what is meant by the path
of a system of points. To get at this we calculate the mean
square of the displacements of a system of pomts when they are
displaced : the square root of this. Hertz calls the displacement
of the system of points. If there is a mass at each point, then
the displacement of the system is the square root of the mean
squares of the displacements of the points, each multiplied by
the mass at it. Thus, if s be the displacement of the system,
and s-^s.,. Sec, the displacements of each point of masses m^m.,,
&c. Then

(w/j + OTj + .

)i'- = >n^s{- + >n„s^ + .

By taking ij, /„, &c., as the displacements in the element of
time, we evidently get a similar expression for the velocity of the
system, and for its acceleration. The mean square of the
velocity of the parts of a system is well known in connection
with the principle of least action. P'urther than this, however.
Hertz defines the angle between two displacements. This is
defined by the equation

(;«i + OT2 + . . . . )w'cose

^(wiijJi'cosoi + m..s..^./ cos a., + ....)

s and s' being the two displacements of the system as calculated
above, and ^i^i', &c., the two displacements of each point and
tti, o.., the angles between these latter, then e is the angle
between .( and s'. Hertz remarks that these can all be very
interestingly expressed in terms of space of multiple dimensions,
in which analytical diagrams are supposed to be drawn. This,
however, represents the real by the unattainable. There follow,
then, several chapters expressing these displacements in terms
of various systems of coordinates, and discussions as to the con-
ditions that the connections of a system should fulfil in order
that they may be represented by equations not involving
differentials. The curvature of the path is here studied. It

is defined as c = —, and from this it follows that, representing

.A-

by -v", &c.

.).-^ = 2i'{«iAi"- + j'i'"-^-t-=i"=).

The problem then of making the path of the system
straightest, is to make c a minimum consistently with the
connections of the system. Now, in accordance with his
assumption that the connections of the system are linear
ditTerential equations of the foim

2,'P,.v\ = o,

whose differentiation gives

we are to determine the minimum value of

•zr^.x"

vhen

in = /«! I- /«o + . . . .

In determining the variations of these, we must recollect that
the positions and direction of displacement, i.e. the first
differentials of the system, are supposed given, and that it is
only the second differentials that can be varied in order to make
c a minimum. Calling, then, a system of indeterminate co-

NO. I316, VOL. 51]

efficient \, y., &c., corresponding to the equations of condition,
we evidently get a system of equations of the form

"'•.<"i H- 2,'P,\ = o,
m

which are sufficient to determine the second differentials re-
quired.

From this form of result one can see how the ordinary
equations of moiion are derivable from the conception of the
straightest path, and how, when dealing with part of a system,
these indeterminate coefficients introduce what are equivalent to
forces. This method of deducing the equations of motion lends
itself particularly well to the deduction of the principles of least
action, and the other general methods in dynamics. So far, he
deals with (ree systems subject only to internal constraints. It
is where he investigates how to deal with parts of systems that
he requires to consider the nature of the constraints joining one
part to another. For this purpose he defines two systems as
coupled when coordinates can be so chosen that one or more of
them are the same for both systems. Force is then defined as
the action one system has on another. Now, when a co-
ordinate is the same for two systems, one of the equations of
condition is/ = p , p and/' being coordinates of the coupled
systems, and for this equation the coefficient P becomes the
same in the two systems, being uniiy for each, so that the
equations of motion involve the indeterminate coefficient
\ corresponding to this equation equally wth reference
10 each system. It is thus that the equality of action
and reaction appears, being thus bound up with the
constant equality of the common coordinate. This seems to
be where the assumption that the connections are rigid
is introduced. When rigid bodies act upon one another by
non-slipping contact, certainly the coordinites of the point of
contact are common to the two systems. It is also quite evident
that if we assume rigid bodies acting upon one another by
contact only, we can have no potential energy, and all necessity
for talking about the forces disappears. In Hertz's system there
are no forces like -N'ewlon's acting between bodies which have
no common coordinate, like the earth and the sun. We would
have to invent connections to explain the motion before we
could be certain that action and reaction are equal in this case.

The proof of the principle of virtual velocities by substituting
for the forces between parts of a system a number of pulleys
which produce the same effects, is quite analogous to Hertz's
supposition that the actual connections are by rigid bodies. It
is not, however, liable to the ol'jeciion that the connections may
become tangled, for it is only applied to the case of infinitesimal
virtual displacements, while Hertz postulates the possibility of
his connections existing as the real ones for all time, and
throughout all finite displacements of the system.

The work considers many other matters, and shows how all
the general methods in dynamics are deducible from his funda-
mental postulate of the >traightest path. It includes discussions
on how best to deal with systems whose connections do not in-
volve differentials, how to treat cyclical coordinates, and many
other matters. It is most philosof,hicaland condensed, and gives
one of the most — if not the most — philosophical presentations of
dynamics that has been published. It is worthy of its author :
what more can be said? G. F. Fitzgerald.

PSEUDO-SATELLITES OF JUPITER IN THE
SEVENTEENTH CENTURY.

TN the New York Nation for January ii, 1S94, Dr. D. C.
■*■ Oilman, President of the Johns Hopkins University, called
attention to an ineresting letter from John Winthrop, jun., to
Sir Robert Moray, concerning the satellites of Jupiter. In this
letter, which was written Irom Hartford, Connecticut, on
January 27, 166J, Winthrop described an observation of
Jupiter which he had made on the night of the previous
6th of August, when he had very distinctly seen five satellites
about that planet. He was naturally " not with out some con-
sideration wheiher that fifih might not be some fixt star with
which Jupiter might at that tyme be in neare conjunction,"
and expressed the wish that more frequent observations might
be made upon ihat planet with a view to ascertaining whether
it is not impossible to discern a fixe<l star, when it is so near
to the planet as to appear '" within the periphery of that single
intuitus by alube which taketh in the body of Jupiter," and if

2S6

NATURE

[January 17, 189 =

so, whether his star is not a new satellite. He further pro-
ceeds:—" I am bold the rather to mention this as an inquiry
whether any such number of Sitellitesor moons hathbeenc scene
by your honor or Mr. Roolce [? Hooke] or any mathematitians or
other gentlemen that have good tubes and often have the
curiosity to view the planet, for possibly it may be new to me
which hath beene more usually ItnoAne by others, though the
notion of such a ihinije is not new to my selfe, for I remember
I mett with the like narration many years since in a little
booke in'ituled PhilosophiaNaturalisperJoh. Phociliden, though
then I thought that was but a mi-take of some fixed Starrs."
Now that Prof. Barnard ha- discovered a genuine filth satellite
of Jupiter after the lapse of nearly three centuries since Galileo's
telescope detected the Medicean stars, a greater interest is given
to those imaginary satellites which from time to time have
claimed a place in the solar system. In .-i paper in the Johns
Hopkins University Cir.iilar for last May (referred to in
Nature, vol. I. No. 12S3, p. ii3\ Mr. Frank H. Clutz has
given a probable identification of Winthrop's supposed satellite
with B A.C. 644S In a postscript to his article it is pointed out
ihit the work to which Winthrop refers is presumably the
" Philosophia Naturalis, seu Physica Vetus-Nova '' of Johann
Kokkens (born at Holwarden in Frieiland in 161S ; died at
Franeker, February 19, 1651). At President Oilman's sugges-
ti m, I have followed up this clue, and have succeeded in
examining the work in question. I find that it contain- more
than a casual reference to additional satellites of Jupiter ; in
fact, a whole chapter is devoted to a discussion of certain ob-
servations, which seems to be sufHclently interesting to deserve
a 'lief notice.

r.iocylides' treatise was published at Franeker in 165 1, shortly
after the death of the author. On the title-|>age it is described
a; wr iten "Ab Eximio Viro/JoH Phocyliue Holwarda/
L .\. M. Med. Doct. & Philosophiae,/dum viveret, Proless.
Ordinario." There is also a portrait. The third of the three
parts into which the book is divided is entitled " Physica Cte-
testis, " and it is doubtless this portion of the Philosophia
which Winihrophad in mind when writing his letter to Sir Robert
Moray. It is not Phocylides himself who claims to have dis-
covered new moons of Jupiter ; nor does he believe in their
cx:stence. On the contrary, he treats the supposed ob-ervaiions
with the severest disapprobation ; and while in general he is
enthusiastic over the revelations which the telescope had
already made and was daily making, this particular di>covery,
which he regards :is spurious, rouses him to the mosi strenuous
exertions in order to efi'ect its refutation The discoverer, by
-Tme .-Vntonius Maria Schyrleus dc Kheita, stated that he had
en, not one, but five new satellites of Jupiter, all farther
I'-moved from the planet than the four Galilean tn ions, ami
revolving in a contrary direction. Phocylido' account ol the
matter may be briefly summarised as follows: First he refers
to five stars near a certain kntjwn s'ar ol the four h magnitude.
They are "intra duodecimum <S decimum quinium Pi-cium
gradum " (p. 205) "versus sinisiram secundum Signorum suc-
cessionem." (p. 205 and p. 2S4.)

These stars, he continues, have given rise to no little con-
troversy among learned and experienced astronomers (astro-
philos,' whether they are fixed stars or erratic, and, more
particularly, whether Ihry are companions (commilitune>) of
jupiier. The iliscusiion ol this point is then posiponed.
Ch.ipter xvi. treats of the number of the planets and iheir
division in kind. Doth satellites and planets proper are in-
clu'led in the term "planct.-e. " .Mier rejecting the sun from
his ancient place among the seven planets, and adiling 10 their
number the two lalcronts atioul S.iturn and the four ab ju'
Jupiter, discovered in ihc "current century by ihe aid of nevi-
and admirable instruments, such as Tubi Ojitic , specula, and
oiheriol the same son," hr adds the Earth to the twelve hitherm
ciljtaincd. It is thus ccriam, he says, that there are at least
ihirlr'-n planets, sine-; it is not yet known whether Mars, Venu-,
anri Mercury have any ia/erottts rev -Ivirig an lut them. " lin
as to the five other circuinjovialcs which P. An'on. M.ir. d
l<hcii:i lioasts that he has observed and called Urban Oc a-
viaii.t, learned men are justly in doubt whether they should \»
referred to the fixed or 10 the wa'.dering stars." Nothing;
fiirihcr is aHile<l at this place, but he prr>ceed- to divide ih>
tliiriccn planets into primary anil secon^lary. The former (>ix
in nunifier) arc named in order from Mercury to Saturn, wrd
the Faith in the Sun's former place. 1 he l.itter ate .Saturn'-
two, anil Jupiter's four satelliies. The seventh is the Moon
Anyone who doubts this, he ailils, will be convinced by what ii

NO. 131b. vol.. 51 j

soon (o be said, as well as by the onsiderations contained in
the chapter " De Lunni; corpore & motu." After several
interesting chapters, including one on Saturn and his laterones,
and another on Jupiter and the Medicean stars, we come to
chapter xxi., entitled " De Pseudojovialibas : & priorum
consectaria." Phocylides' attitude is at once disclosed. He
refers to the pseudo-discoverer as "quidam .\ntonius Miria de
Rheiia, (homo in Pap.itu arrogans, invidus, judicio proeceps &
fatuu', aliorum gloriam pro propria injusie & cu n pudoris
oblivione captans & vindicans)."

The discovery was alleged to have been made at Cologne near
the end of the year 1642, and was announced in a letter to
Puteanus. Hut it so h.ipjiened that Hevelius had noticed and
described these very stars several months previously. His
observations were mule in August 1642 and the succeeding
mmihs, and Phocylides regards the claims of Rheita to have
been the first to discover them as " freiidum mendacium," as,
by his own admission, he did not ob-erve them before the end
of the year. The identity of Rheita'- peu'lo joviales with
these fixed stars is shown by a omparison of the actual
positions of Jupiier on the dates when Ihe observations were
made. Our author poin s out that on Decem*ier 29, the day
ol Rheita's discovery, Jupiter occupied the same position as
on the previous 4th of St-p ember, when Hevelius observed him
and noticed the five stars. This position is defined by Pho-
cylides in the words, " decimo tertio gradu Piscium, cum quin-
decem minutis. " Again, Heveliu- saw Jupiter on .-Vugust 28
" in dtcimo quarto gradu Piscium, cum quindecem minutis,"
where Rheiia observed htm on January 4 ol the following year
(16 (3). The new circum-'oviales ate then, says Phocylides,
none other than the stars recently discovered in .\quarius.
They do not move round Jupiier, as they would do if ihey
were second \ry planets, and are therefore fixed stars, " mane-
buntque [fixx-| usque ad sxculi consunimationem." They were
observed by Hevelius to remain stationary, while Jupiter left
them behind him. Phocylides challenges any doutiter to look
for these stars himself, when all five will be lound in their
original position and at the same distances one from another.
He concludes with the words (p. 289); " llallucinatur iiaque
cr.i-se & inani ui'n - i;lor o .1 Rtieiia se ipsum utilUi."

Tne following will ihow furiher li^hl on Rheita's
tendency 10 fo m hasty conclusions. According to Phocylides
he declared that he had ob-erved three of the Medicean stars
t) be in a straight line, but the loirth "tanlam obiinuisse lati-
tudinem, qua;, -i ex centro Jovis liccentricum ad ilium excur-
rentem mctiamur, ad qum lecein gradus excrescat." This, says
our author, is contradictory to the tibservations ot all " mathe-
maticians," who unintmiusly agree that the .Medicean stars
never recede from Jupiter in latitude more than three minutes,
whether to the no'th or to the south. He then s'aies that this
fourth star, s > far from being a true Galilean satellite, wis not
even a pseudo-jovial, but another fixed star. Gas-endi observed
the satellites on the same night, and saw all four in a straight
line, the second lightly to the north ; but they were ilifferently
dis osedwith regard to Jupiier. In all i)robal)ibty, Phocylides
concludes, the fir.st (innermost) satellite was obscured by the
planet, if, as is likely, the observations were not made at pre-
cisely the s.imc hour j for Jovial Mercury (is he is called) runs
his course roun<l Jupiier in a few hours more than a wliole d.iy.
Pnocylt'les supposes tna', as Rheita was well aware ihii there
*er^ four satellites, he mistook this fixed star for the fourth
-atcllite.

Tne existence of Rheita's new satellites was opposed by
Gassendi in his " Juilicium dc novem stcllis ciica Jovem visis
(-ee Drlam'irc, "llis. dc ^A^t. Mod.," ii. p. 351), and by
Hevelius in his " Selenograiihia," ih. p. 437). l.obko«ilziu»

■ lefcmled Rh-ita against Ga.sen li (" Ph .cylides," p. 295).
Delainbre devotes several partes to Rheita, or Sohyrle, cik'
i;iv s some av:count ol his work " Oculus Kioch et lilirf, sive
l< idius siilere iniysticus." Antwerp, 1645. In this book,
a,.cjrding to Delamore, he admits .hat dc has not

■ uccci^ded in oiiserving his satellites agnin, but asserts
a lew that he noticed changes in their mu ual distances.
He explains their di-appeatancc by connec ing ihetn with
v.irialile stars, which he supposes to have l.irgc orbits and long
rev.d.ilions. He believed, moreover, thai the spots of the suns
*cre pi met-, an I that the -un i sell rotated lUi once in a year.

Phocylides also mcniioi.s circuin-inar tales ami circuin-
-.iluinales, which, no less than the ciicunijovi.iles, must be
held to lie lixcd stars.

Ii will thus ue »een that VVinlhrop was ri^hl in remembering

January 17, 1895]

NATURE

287

Phocylides' treatise as a work in which the discovery of new
satelliles was mentioned. But apparently he did not remember
very accurately the position assumed by the author, for the
book contains but little to encourage an observer in the belief
that he has discovered new satelli'es.

It is perhaps worth noticing that the Philosophia was pub-
lished less than fourteen years before the date of Winthrop's
letter ; it must therefore have been quite a new hook when
Winihrop perused it, as he says, " many years since."

Charles W. L. Joh.n'son.

UNIVERSITY AND EDUCATIONAL
INTELLIGENCE.

Oxford. — Prof. J. Burdon Sanderson has been appointed
Regius Professor of Medicine in succession to .Sir Menry W.
Acland, whose resignation was announced last Term. In
accepting ihe Regius Professorship, Prof. Sanderson vacates
the \Va)nflete Chair of Physiology, which is more valuable in
a pecuniary sense. It is naturally a matter of regret that he
should formally sever hi-^ connection with the school of
Physiology which he may be said to have created in 0.\ford,
but it is recognised that no better appointment could have been
made lo the headship of the Medical .School which he has done
so much to encourage, and who^e in'eresis he will have further
opporluniiies of promoting in his new position.

At a meeting of the Royal Statistical Society held on
Tuesday, a paper was read, by Mr. L. L. Price, on " The
Colleges of Oxford and Aijricu'tural Depression." The
accounts of the Oxford and Camhtidge Colleges have been
published year by year for some time pa-t, and in Mr. Pace's
paper the accounts of the Oxford Colleges for the years 1SS3-93
were brought under review. The gross external receipts of the
Colleges were in iSgjsome ;^ii,oro less than in 18S3, and the
net external receipts some ^^13.000. Though the external
receipts are not entirely derived from agricultural estates, it
seems within the facts to regard agricultural depression as
resi'onsihle for a loss of upwards of ;^6o,ooo of income
in 1S93. Turning to the eflVcts of the depression upon the
emoluments of the Heads, Fellows, .Scholars, and Exhibi-
tioners, to which the College revenues are mainly devoted, it
appears that these effects have been mitigated by the circum-
stances that the external receipts are not exclusively agricultural,
and that the emoluments aie also partly derived from internal
receipts and from Trusts. Siill the emoluments of the Heads
have lallen from ^'22, 811 to £20, 905, and of the Fellows from
.^83,820 to ^^74, 749. The emoluments of the Scholars and
Exhibitioners have however increased from .^£^44,776 to
;{^48,37S. and their number has grown by upwads ol ninety ; and
if the increased contributions made by the Colleges to the
Uiiiversity are taken into consideration, the fall in the total
payments is only about 5 per cent. But there are Colleges,
where diminutious have occurred of more than ?5 percent, in
the emoluments of the Fellows, and the figures generally
are altr-red con-iderably for the worse by eliminating a few
prosperous Colleges.

Camhridge. — Mr. A. Hutchinson, Fellow of Pembroke
College, has been appointed Demonstrator of Mineralogy
and Assistant-Curator of the Museuuu, in place of Mr. Solly,
who has retired.

The Downing Professor of Medicine (Dr. Bradbury)
announces that the newly-organised Museum of Materia Medica
and the Pharmacological Laboratory are now open dady to
students of medicine, and that demonstrations will he given
therein liy Mr. Mar-hall, Ihe assistant to the Professor.

Dr. Gaskell, K. R S., has been appointed an additional
member of the Board for Biology and Geology.

The Royal Agricultural Society has now issued its revised
regulations and syllabus for the society's senior examinations,
framed in accordance wiih the important modifications recently
decided upon. The council have resolved to place annually at
the disposal of their educati'in commi'iee five lile memberships
of the society, to be awarded to the five candidate- who >tand
highest on the list of winners of first-class certificates, and who
ol>t.iin not less than two-thirds of the maximum number of
marks. The gold medal of the society will be bestowed upon
the candidate who -tands highest on the list of winners ol life
memberships, provided that he hasoiitained not less than three-
fourths of the maximum number of marks, and silver medals

NO. 1316, VOL. 51]

upon the other winners of life memberships, including the can-
didate at the head of the list, if he does not reach the standard
required for a gold medal.

The Association of Head Masters held its first meeting as
an incorporated body on Thursday last. One of the items of the
agenda was a paper in which Mr Stuart described the usual
practice of teaching science, and said most of them were satisfied
that such a system had no educational value at all. -\11 ex-
periments must be capable of being performed and the observa-
tions made by the students. The experiments must be chiefly
quantitative and especially at first. Books and lecture
demonstrations must be avoided. He thought that a good
grounding in science might be given by doing practical work in
an ordinary class- room, upon common tables, with home-made
apparatus. The following resolutions were afterwards passed
by the meeting : —

(a) " That the association is of opinion that examining bodies
should encourage a more rational method of teaching science,
by framing the syllabuses in such a manner that the practical
work required may be strictly illustrative of the theoretical
instruction given."

(/') " That it be referred to the general committee to appoint
a small sub-committee, so that a report may be presented to
the next summer general meeting containing detailed suggestions
which it is proposed to make to examining bodies concerning
examinations in science."

The Research Scholarship given by her Majesty's Com-
missioners for the Exhibition of 1851, to Mr. Edward Taylor
Jones, of the University College of North Wales, in 1892, has
been renewed lor a ihird year. Such renewal is only made in
cases of exceptional merit, where valuable scientific results are
likely to be obtained by a continuance of the scholar's research
work. Mr. Jones has just completed, at the Uuiversity of
Berlin, an e>perimen!al investigation solving an important
problem in magnetism. An account of the research has been
communicated to her Majesty's Commissioners, aud will shortly
be published.

The Professorship of Mathematics in the Government Train-
ing College, Ireland, vacant by the retirement of Principal
Corbctt, has been filled by the appointment of Mr. Dilworth,
of Trinity College, Dublin.

SOCIETIES AND ACADEMIES.

Paris.
Academy of Sciences, January 7. — M. Marey in the
chair. — A list of the present members, foreign associates, and
correspondents of the Acidemy is given. — .M. .\. Cornu was
elected Vice-President for 1895 — Pre 'aration, in the elec-
tric furnace, of graphites fotsonnants, by -M. Henri Moissan.
For all varieties ol graphite prepared by intense heat, the
tempenture of intumescence alter shaking in nitric acid is about
I65°-I75° C. They resemble natural graphites in this and other
respects, hence the probability that the latter have been pro-
duced at a very high temi eraiure under moderate pressures in
masses of iron which have since disappeared. — The vasomotor
nerves of the veins, by M L. Ranvier. From the results of
experiments quoied, the author concludes that veins as well as
arteries are supplied with vasomotor nerves. — On the first
scientific voyages of the Princess Alice, by Prince .Vlbeit I. of
Monaco. — .4ii addition to Le Verricr's theory ol the movement
of Saturn and rectification of the Tables, by M. A. Giillot. —
On the approximate dcvdopment of the perturbation luuctioo,
by M. N. Coculesco. — On roots common to several equations,
by M. WaMicr D)ck. — On ihe theory ol a system of ditterential
equal ions, b) M. A.J. Siodolkicviiz. — On the ihcuryoi exchange-
able substitutions, by M. Demeczky. — On the absoluie value of
the magnetic elements on January I, 1895, by -M. Th. .Moureaux.
The values are given for (A) Pare Sami-Maur, Long, o' 9' 23"
E. and Lat. 48° 48' 34" N. ; (B) Perpignan, Long, o' 32' 45" JE.
and Lat. 42° 42' 8' N.
Elements. Abs. values Jan. i, 1895. Secular variation in 1394.

Declination ... (A)i*5 laV ••■ (B)°4 3'4 -(A)-s'3 ... (B)-s'o

Inclination ... 65 4*9 ... 6099 ... -12 ... -08

Hurizontal

component ... 0*19641 ... o"2234S ... -fo'oooi; ... 4-0*00025

Vent- .*il com-
ponent 042277 ..." 0*38961 ... -000003 ... -ho*oooai

Total force ... 0*4^617 ... 044914 ... -fo 00005 ■•• -1-0*00031

2SS

NA TURE

[January 17, 1895

Use of ihe critical temperature of liquids for the recognition of
their parity, by M. Raoul Pictet. A convenient method of de-
termining the critical points of liquids is described. Any im-
purity causes a dilTerence in the critical temperatures in the same
sense as the difliirence produced in the boiling points, but in
the foiiner case the difference is of far greater mai;oitude than in
the latter. — On the qualitative separation of nickel and cobalt,
by M. A. Villiers. The author avails himself of the property
of sodium tartrate in prevenling the precipitation of nickel
sulphide while allowing the complete precipitation of cobalt
sulphide. Tartaric acid is added to the clear solution of the
two metals, then soda (not potash) in large excess and hydrogen
sulphide is passed. The nickel passes into the filtrate as a
nearly black solution, mere traces give a brown tinge. The
method is not quantitative. — Some points in the spermatogenesis
of the Selacians, by M. .-Vrmand Sabatier.— On the genesis of
intestinal epithelium, by M. Ktienne de RoaviUe. Observations
confirm the author's views that : (l) The conjunctive tissue con-
tinues more or less, during life, to be the matrix giving rise to
the elements of other tissues ; it is a pjst-embryonic blastoderm.
(2) Epithelial tissues are only, in most cases, the forms limiting
the free surfaces of conjunctive tissue. — Physiological researches
on the Lainellibranchs ( /a/tri dcciissala, Sec), by M. Fieri. —
On some lakes in the .\lps and Pyrenees, by M. A. Delebecque.
The depths and altitudes of most of the important mountain
lakes are given.

Berlin.

Physical Society, November 30, 1S94. — Prof, von Bezold,
President, in the chair. — Dr. Aschkinass described his experi-
ments on the influence of electric waves on the galvanic
resistance of metallic conductors. Gratings made of tinfoil
when placed near a Hertz exciter showed a diminished resistance
which was quite independent of the action of light due to the
primary sparks, and was persistent after the cessation of the
electric oscillations, but could then be restored to its original
value by mere mechanical percussion. A series of experiments
proved that it is really the electric waves which altered the
resistance of the grating, and the results were extended toother
metallic conductors. 1 he speaker drew attention to analogous
observations made by English and Swiss physicists who had
found that filings of iron and other metals enclosed in glass
tubes had their resistances altered by electric sparks discharged in
their neighbourhood. In their case, also, the original resistance
was restored by mechanical vibration. — Dr. Gross spoke on the
electrolysis of a solution of mixed nitrate and sulphate of silver
to which a little nitric acid had been added. Silver was de-
posited on the kathode, and a black substance on the anode ;
the latter he had not as yet obtained free from silver, but it did
not ontain any sulphur, although 60 percent, of sulphuric acid
had disappeared from the solution.

Physiological Society, December 7. — Prof du Bois
Reymond, President, in the chair. — Prof. L. Lewin gave an
account of some experiments made with an alkaloid obtained
from a North Mexican cactus called " Peyotl." It is well known
that this plant has an intoxicating action, and in larger doses
produces sleep and a state of nervous excitation accompanied
by a so-called "power of prophesying," similarly attributed to
the sulphurous exhalations of the temple at Delphi. Sm.nll
doses of the alkaloid when given to frogs produced tetanic
cramps and a greatly increased reflex irritability, analogous 10
strychnine ; but with this difference, that by carefully apportion-
ing the dose the effects were permanent for several days.
Similar results were obtained with rahbits, and Prof. Lewin
regarded the new alkaloid as specially adapted to further the
study of Ihe nature of tetanus. In rabbits it was noiiced that
durmg each paroxysm of cramps, the bloixl-vessels of the ears
were widely distended. The speaker had also found alkaloils
with powerful actions in many specie^ of Cactus hitherto regarded
as harmless by botanists, no: alily oneclusely resembling ciir.ire. —
Dr. G Joachim had invc-.tiga^ed sphygmcigraphically the effect
of suspension by the head on the circulation, and in the case of
a number of invalids, of whom some were suffering from heart-
disease, had observed only a alighily increased frequency of
pulse, which is probably merely a'triiiutabic to psychic
excitation. — Prof. Gad communicaied Ihe results of an investi-
gation, made by n new method by Mr. .Seelcr, of Cleveland, on
the terminations of motor nerve in muscles, which had shown
that in addition to the motor fibre a non-medullated fibre leaves
the sheath of llcnie, and isilistributed to Ihe capillaries of the
muscle-fibre, whereas the medullalcd motor-fibres spread out
o the muscle itself.

NO. 1316, VOL. 51 ]

BOOKS, PAMPHLETS, and SERIALS RECEIVED.

Books. — Lo^ic ; Dr. C. Sigwart. tr;inslatcii by H. Pendy. 2 Vols., 3nd
edition (Sonnen5chcio) — Lcs .\bimcs : E. A. Marlcl (P-iris, Delagrave). —
Essays on Rural Hygiene: Dr. G. V. Poorc, rnd edition (Longmans). —
AnDuairc de I'.Acadimie Royalc des Sciences. &c., de Belgique. i3<>5
(Bnixelles). — .\slroDOmischc Chron-iloEie : Dr. \V. F. Wislicrnus (Leiprig.
Teubncr).— Handbuch dtr Theorie dcr Linearen D-fTerenti;«Ul':ichuncen :
Dr. L. Schlesinger. Erster Band (I^eij-zig, Teubner). — Laboratory Exer-
cises in Botany ; Prof. E. S. Bastin(Philadelphia, Saunders). — Smithsonian
Report. iSq5 (Washington). — Geolocical Sirvey, Alabama, Report on the
Geology of Itie Craslal Plain of AIaban>a(Montgrmery, ALibama). — 'fables
and Directions for the Qualitative Chemical .Analysis ot Moderately Com-
plex Mixtures of Salts : M. ^L P. Mtiir (Longmans).

Pamphlets.— Eighth Annual Report of the Liverpool Marine Biology
Committee ard their Biological Station at Port Erin : Prof. HcrdmanlLiver-
pool, Dobb). — On the Search for Coal in the Soiith-East of England ; W.
J. Harrison (Birmingham).— Eine Discussion i^cr Ki;ifi der Chemischen
Dynamilc; Dr. L. Stettinhcimcr (Frankfurt a.^L, Bechhnid).— The Varie-
ties of the Huni.-in Species; Prof. G. Sergi (Washington). — Royal Horti-
cultural Society Report for 1894-5 t^"ic^o^^a Street). — Ditto, Arraogemenis
for 1S95 (Victoria Street).

Serials.— Geographical Journal, Jantiary (Stanford). — American
Journal of Science, January (New HavenV- Catena Chimica Italiana,
Anno xxiv. 1804. Fasc. vi. (Roma) —Proceedings of the Physical Society of
London, January (Taylor). — Journal of the Chemical Society. January
(Gurney). — Ditto, Supplementary Number (Giirney). — Record of Technical
and Secondary Education, January (Maemillan). — Beili.'ige zur Petro-
graphie dcr OstHchen Centralalpen speclell dcs Gross- Vencd'gerstockes :
Dr. E. Weinschenk. I. a nd 1 1. (Munchen). — Morphologisches Jahrbuch, 22
Band, 2 Heft (Leiplig , Engelmann).— Jouroa! of the Franklin Institute,
January (Pilhadelphia). — Journal of the Royal Hrriicultural Society.
January (Victoria Street).— Engineering Magazine, January (Tucker).

CONTENTS. PAGE

Epigenesis or Evolution. By G. C. Bourne .... 265

Coal- Dust and Colliery Explosions 268

The Mode of Life of Marine Animals. By VJ. A. H. 269
Our Book Shelf:—

Clowes: "Elementary Qualitative Chemical Analysis" 270
Muir : " Tables and Directions for the Qualitative
Chemical Analysis ofModerately Complex Mixtures

of Salts" 270

Francis : " Laboratory Exercise Book for Chemical

Students" 27°

Parker: " Elements of Astronomy " 270

Letters to the Editor:—

Exploration at Ruwenzori.— G. F. Scott Elliot . . 271
The .\lleged Absoluteness of Motions of Uotalion. —
A. B. Basset, F.R.S. ; Prof. Oliver J. Lodge,

F.R.S 271

The (Quarrying of Granite in India.— Dr. H. Warth 272

Storm Statistics at Bidston.— William E, Plummer 272
Peculiarities of Psychical Research.— Prof. Karl

Pearson; H. G. Wells 273

The Sus]iended Animation of Snakes. — S. Garman ;

W. Kennedy 274

"Finger-Print" Method.— Kumagusu Minakata . 274

A While R.iinbow.— Rev. Samuel Barber ... 274

American Topography. By A. Fowler 274

Life at the Zoo. {/lluslraleJ.) 2^6

Intercolonial Astronomy and Meteorology .... 278

Notes 278

Our Astronomical Column : —

SCephci 282

The V.atican Observ.ttory 282

An Indispensable Annuaire 282

The Unification of Civil and Astronomical Days . . 282
The Foundations of Dynamics. By Prof. G. F.

Fitzgerald, F.R.S 283

Pseudo-Satellites of Jupiter in the Seventeenth

Century. Hy Charles W. L Johnson 285

University and Educational Intelligence 287

Societle^ <nd Academies . . 287

Books, Pamphlets, and Serials Received 288

NA TURE

289

THURSDAY, JANUARY 24, i895-

A BAD METHOD IN TEXT-BOOKS.
Lehrbuch dcr Verglcichenden Anatomie. Von Arnold
Lang, o. Professor der Zoologie und vergleich-
Anatomie, Zurich. 4te Abtheilung : Echinodermen
und Enteropneusten. (Jena: Fischer, 1894.)

PROF. ARNOLD LANG completes, by the pub-
lication of this fourth part, his treatise on the
comparative anatomy of Invertebrata. As the suc-
cessive parts of this work have appeared, the author has
changed to a considerable degree the limits of space
which he appears originally to have contemplated, and
has consequently treated those groups reserved for later
volumes at greater length than that which he permitted
himself to occupy in the first part of the work. We note
that he now proposes to rectify this inequality by the
production of new editions of the earlier part of the
treatise.

Prof Lang remarks in an interesting "Nachwort,"
that "man hat es vielfach getadelt " — that is to say,
"complaints have been very generally made" — that the
names of authors are not cited in the discussions which
constitute the text of his work. I confess that I am
most emphatically in agreement with those who have
i ■"getadelt"; and I do not think that Prof. Arnold Lang's
i contention is either correct in itself or sufficient (if it
were correct), when he asserts that the book would have
been double the size it is, had he given an impartial
I account of the historical development of the knowledge
■of the facts which he describes, with reference to the
names of the most important authors. There are, it
seems to me, three good reasons for adopting the method
to which Prof. Lang objects. Firstly, such a method
■(namely, a historical method not carried beyond the cita-
tion of the works of the chief contributors to surviving
doctrine) is the most natural for the mind of the student
to follow, and gives him the truest appreciation of the
present condition of knowledge on any topic, and of its
probable future development ; secondly, such a citation
of the names of really surviving authorities — that is to
say, of authors whose work is at this moment admitted as
being the original and approved source of observational
record, or theoretical conception still holding its ground
- is, as a mere mitter of bibliographical reference, of far
more service to the student than an indiscriminate list
of memoirs at the end of a chapter (such as Prof
Lang gives) without any indication of the contents of
the memoirs named ; thirdly, that such a citation is the
bare justice to his predecessors and contemporaries
which every teacher of zoology (or other advancing
science) should fee! bound to accord, and should, I ven-
ture to say, gladly and scrupulously take trouble to
ensure for those whose original work he has appropriated
and accepted.

I confess that 1 feel sensible of something ungenerous
and even unfair when I read the long and careful state-
ments as to the skeletal and other systems of the Echino-
derms (300 piges), illustrated by admirable copies of
■other naturaliits' drawings, made in the present volume
by Prof. Lang, without citing in his text a single name
NO. 1317, VOL. 51]

of those to whom he and the world in general are indebted
for all this knowledge. After all, it may well be ques-
tioned whether any man of science is justified in making
statements, even in a text-book, as though he himself had
investigated and was responsible for the accuracy of
these statements in virtue of his own observations on
the objects described, when all the time he is simply
stating what this man and that man have seen, and
he has not seen, though he omits to mention the name
of any of those to whom he is indebted. When
such a method is adopted, one is quite unable to dis-
tinguish the individual opinions of the author from the
mass of second-hand information which he pours out.
A very simple introduction of the phrases, '' as was first
shown by X," or "according to the observations of Y,"
or again, " an observation which I can confirm, as it has
been called in question," would alter the whole signifi-
cance of Prof. Lang's discourse, and make it not only
much more valuable, but much more interesting. At the
same time, let me hasten to say that every one will at
once accept Prof. Lang's statement, that his object in
ignoring the names of zoologists has been to secure
brevity. My contention is that the end has not
justified the means.

Take, for instance, the so-called "apical" nervous sys-
tem of the Crinoids. The discovery of this remarkable
and altogether improbable nervous system by that staunch
and unwearied naturalist. Dr. W. B. Carpenter, in his old
age, is one of the most delightful episodes in the history of
comparative anatomy. He made the discovery after he
was seventy years of age, and no one believed that his in-
terpretation of his observations was correct when he first
announced it. Old as he was, he lived to see his discovery
confirmed and accepted on all sides. This extraordinary
nervous system is described at some length , and explained
by figures in Prof. Lang's book ; yet the name of Dr.
Carpenter is not once mentioned in connection with it,
and the figures given (p. 966) are taken from and
ascribed to Beyrich (!) and Carpenter's son Herbert, who
merely worked out, long after his father's complete
publication, some details of the old man's discover)'.
On the other hand, the mere accident that the coeca
of the lantern-membrane, discovered by Prof. Charles
Stewart in the Cidaridse, have no special name, results
in a recognition of his interesting discovery by the title
of the " Stewartschen Organen."

The unsatisfactory character of Prof. Lang's method,
if we regard his book as one for reference and assistance
in tracing the more recent discoveries, is well exhibited
in the section of little more than one page (pp. 1036, 1037)
on the axial organ of Echinoderms (dorsal organ, heart,
pseudo-heart, renal organ, plastidogenous gland, ovoid
gland, lymph gland). Here the space assigned by the
author seems to be singularly out of proportion to that
given to other topics, and we get not only the very
scantiest description of the axial organ in Asterids,
Ophiurids, Echinoids, and Crinoids, but no indication or
reference luhaUvcr to ampler sources of information.
Since this is really one of the critical subjects of recent
investigation in Echinoderm anatomy, it is to be regretted
that Prof Lang says so little about it.

Whatever faults one may find with Prof. Lang's book,
there is no doubt that it also has merits, and will be

O

2 go

NATURE

[January 2^, 1895

found to contain a survey of Echinoderm morphology
more extensive than that accorded to the morphology of
other groups by the same author, as well as some useful
original diagrams, such as that of Pentremites, on p. 96S.

E. R.\Y Lankester.

THE STUDY OF ROCKS.
Lehrbuch der Pitrographie. \'on Dr. Ferdinand Zirkel,
Ord. Professor der Mmeralogie und Geognosie an der
Universilat Leipzig. Zvveite giinzlich neu verfasste
Auflage. Three vols. Svo. Pp.2619. (Leipzig : Engel-
mann, 1S93-94..)

THE appearance of a second edition of Prof Zirkel's
admirable " Lehrbuch der Petrographie " is an
event of no little importance in the history of geological
science The part played by the author of this work in
developing the methods of microscopic analysis, as ap-
plied to rocks, is too well known to require recapitulation
in this place, and the long series of petrographical
memoirs with which he has enriched geological
literature^dealing with the rocks of the -N'orth .-Vmerican
as well as with those of the European continent^are
familiar to all students. While a great number of works
treating of the microscopic study of rocks (including the
author's own "Die mikroscopische Beschaffen heit der
Mineralien und Gesteine ") have appeared during the
twenty-eight years which have elapsed since the first
edition of the "Petrographie" was published, there is
not one among them that qu ite occupies the place of that
excellent treatise — with its wealth of information on the
history anddevelop.nent of petrographical nomenclature.

The rapidity of growth of this branch of geological
science daring the past thirty years, is brought out in a
very striking manner by a comparison of the first and
second editions of this standard work. The first edition
consisted of two thin volumes with an aggregate of 1241
pages; the second edition forms three bulky volumes
with 2319 pages. But this is not all : it is evident to
anyone who peruses these volumes, that, in spite of the
employment of more than double the number of enlarged
pages, with much small type introduced, the author has
found it impassible to discuss in all their aspects the
views of previous authors with the completeness and
comprehensiveness that were so remarkable in the first
edition of the book. The student may be satisfied that
Prof. Zirkel has overlooked little or nothing of importance
in the literature of his subject ; but, not unfrequently, it
will be noticed that in his attempt to deal as concisely
as possible with this vast mass of literature, he has made
statements with respect to the views of the authors quoted,
which are scarcely borne out by a reference to the
memoirs themselves. While, therefore, this new edition
will be invaluable in supplying ample references to petro-
graphical literature, it will not in any way obviate the
necessity of consulting the original memoirs.

As indicating the fulness with which the subject is now
treated, we may mention that the number of pages
dealing with "General Petrography" has increased from
171 to 634. The account given of the optical properties
of minerals and of the structure of rocks, as made out
by the aid of the microscope, is naturally responsible for
a large part of this increase ; the description of the
NO. 1317. VOL. 51]

common rock-forming minerals, which was comprised in
forty pages in the first edition, now requiring no less
than 291 pages. The greatest defect in this part of the
work will be found in the absence of illustrations. Of this
the author is fully sensible, as will be seen from a
reference to his preface ; but, as he justly pleads, the
addition of illustrations could not fail to add to the
bulk and cost of a book that has already grown to
encyclopasdic dimensions.

Every student of geology will naturally examine the
work with the desire to learn what are the present views
of so great an authority as Prof. Zirkel on the vexed
subject of rock-classification and nomenclature. In the
first edition of the book, our author, following the plan
of most German writers upon the subject, attempted to
class rocks according to their structure and mineralogical
constitution, quite irrespectively of their origin, into
simple crystalline rocks (ice, rock-salt, quartz-rock, lime-
stone, S:c.), compound crystalline rocks of granular and
schistose character respectively, and clastic, or frag-
mental, rocks. In the second edition, he departs from
this method, and commences the descriptive portion of
the book with an account of the " Massige eruptive
Erstarrungsgesteine," which occupies no less than 1293
pages. This is followed by an account of the " Krystal-
linische Schiefer" (275 pp.), the " Krystallinische oder
nicht-klastiche Sedimentgesteine " (230 pp.), and the
" Klastichen Gesteine " (125 pp.). It will thus be seen
that the primitive classification into crysialline (simple
and compound) rocks and clastic rocks, has been
abandoned for one in which account is taken of their
mode of origin.

In dealing with the great class of igneous rocks, Prof.
Zirkel has also introduced some modifications of his
original method. In 1 866, he grouped these rocks, ac-
cording to the nature of the alumino-alkaline silicate
present in them, into Orlhoclase-rocks, Oligo'clase-
rocks, Nepheline- and Leucite-rocks, Labradoriterocks,
Anorthite-rocks, and rocks without felspathic con-
stituents. The obvious objections to this classification
were: (i) That many rocks contain several distinct
species of felspar, notably in their pnrphyritic con-
stituents, and in their groundmass respectively ; and (2)
that geologists possess no simple, infallible, and easily
applied test for ascertaining the exact species of felspars
present in rocks. In 1873 (in his " Mikroskopisch
Heschaffenheit der Mineralien und Gesteine"), Prol
Zirkel abandoned this classification for the simple]
division of felspar-bearing rocks into Orthoclastic an
Plagioclastic. This classification, which is facilitated bj
the general presence of twin slrialion as an easily reco;
nised distinction of the plagioclases, has now been ve
generally adopted by petrographcrs. In the work befoi
us, however, the author divides the felspar-bearin|
igneous rocks into two series, distinguished by the pn
dominance of an "alkali felspar ' or of a " soda-li
felspar " respectively. It does not appear to us that an
thing is gained by this new departure, which will co-
pcnsate for the admitted difficulty of applying the tel
for the discrimination of the two classes. AnotW
change in classification which will interest Engli
readers is that, while the separation of volcanic rocR?
into two series, the pre-teitiary (pa'ao-volcanic) an

January 24, 1895J

NA TURE

291

post-tertiary (neo-volcanic) is maintained, the Plutonic
rocks are admitted to be of all ages.

Geologists will, alas, look in vain in this work for
any indication that they may hope for a speedy termina-
tion of the terrible confusion that has so long prevailed
with resrect to petrographical nomenclature. On the con-
trary, they will find that in addition to having to reckon
with the schools of Paris and Heidelberg, as they have
done in the past, they will now have to take account
of a third — that of Leipzig ! With some of Prof.
Zirkel's criticisms of contemporary pateontological
literature, English and American geologists will heartily
sympathise. The employment of such terms as granitite,
^^ranpphyre, &c., with significations different from
those given to them by the authors of th names,
! annot but fail to lead to almost endless confusion,
and ve aie glad to see that the authority of Prof
Zirkel is thrown into the scale against such principles of
nomenclature being adopted ; but in other cases we can-
not but think that his objections to the nomenclature of
other authors are not likely to be sustained by future
workers in this branch of science.

Whether the confusion that now exists can be removed
y any friendly discussion between the representatives
of rival schools — such as those of the international
committee proposed at the late Geological Congress at
Zurich — time alone can show. If this be impossible,
and writers in France and Germany, respectively,
continue to ignore the terminology employed in other
countries than their own, then it appears to us that, if
science is to maintain her cosmopolitan character, only
one method of escape is possible. We must follow the
example of the other natural-history sciences in adopting
the test oi prioiity as absolute and final in our termin-
ology of rocks. That many inconveniences must result
from such a course may be readily admitted ; and it will
not be easy to fix upon the Linnaeus of our science — or
to decide upon the date at which exact petrographiral
literature may be supposed to have commenced. But
almost any trouble and difficulty of this kind is worth
encountering, if we may hope that geologists in the future
will, in speaking of rocks, attain that great desideratum
of "one thing — one name."

In the meanwhile, we are not ungrateful to the author
of the work before us for the enorinous labour and pains
he has taken in wading through the great mass of
petrographical literature ; in furnishing; us with correct
statements concerning the origin and history of terms ;
and in placing on record the decisions he has arrived at
upon miny of the difficult problems that confront us.
The " Lehrbuch der Petrographie " has always been a
standard work of reference ; and, in its new form, it has
become more indispensable than ever. J. W. J.

OUR BOOK SHELF.

Pithecanthropus Erectus, eine Menschenaehnliche
(Jc/>e\i;iiHi:s/or!n aus Jaiia. By E. Dubois. 410, pp.
40, illustrated (balavia, 1894.)

Java, from its geographical situation, being just one of
those court -les where tlie remains of a connecting form
between man and the higher apes would be extremely
likely to or ..ur, zoologists have naturally been attracted
by the title ol the work before us, which proclaims in no

NO. 1317, VOL 51]

uncertain tones that such a missing link has actually
been discovered. A feeling of disapf ointment will,
however, probably come over the student, when he finds
how imperfect are the remains on the evidence of which
this startling announcement is made ; ard when he has
submitted them to a critical examination, he will probably
have little difficulty in concluding that they do not
belong to a wild animal at all. The specimens described
are three in number, and were discovered in strata of
presumed Pleistocene age near a spot called Trinil.
The first of these is a last upper molar tooth, found
during the drying up of a river-bed in the autumn of
i8gi. A month later, the roof of a large cranium was
discovered in the same bed, at a distance of only
about a yard from the spot where the tooth laid.
Finally, in August 1S92, at a distance of some sixteen
yards higher up the stream, a Ie(t femur was disinterred,
which is stated to present much more human resem-
blances than either of the other two specimens. The
bed from which this bone was derived is stated to have
been the same as that from w-hich the oiher two
speciinens were obtained. The author is confident that
all are referable to a single animal ; and we are content
to accept this view.

Especial stress is laid on the femur as indicative of
human affinities ; and here again we are in agreement
with the author, only we would go one step further, and
say that it actually is human. As is pointed out in the
text, this bone has a large exostosis below the lesser
trochanter ; and we believe that such slight differences
as it shows from normal human femora, are due to this
diseased condition. With regard to the skull, which
shows a marked human facies, but an extremely small
development of the brain-cavity, the absence of ridges
on the calvarium clearly shows that it can belong to no
wild anthropoid ; and there apjiears every reason to
regard it as that of a microcephalous idiot, of an un-
usually elongated type. The molar, so far as we can see
from the figure, may likewise perfectly well be human.

Haeckel's '■^Pithecanthropus^' may, therefore, be
relegaied to the position of an hypothetical unknown
creature for which it was originally proposed ; while the
specific name ^'erectus" must become a s)non)m of the
frequently misapplied "ja//^«.f." R. L.

The Planet Earth. An Astronomical Introduction to
Geography. By R. A. Gregory, F.R.A.S. (London :
Macmillan and Co., 1894.)

It is, perhaps, one of the consequences of the antiquity
of astronomy that it is not now usually presented to the
youthful mind in a thoroughly scientific mrnner. The
established truths of the science, in so far as they con-
cern the earth's place as a planet, though once so astound-
ing to mankind, are now so commonpl.ice that the edu-
cational advantages of a study of the phenomena which
brought them to light are frequently overlooked alto-
geiher. .\s In the case ol geography, information rather
than education appears to be the princlp.il aim of astro-
nomical teaching when it is not carried beynd the
elementary stage which it reaches in schools ; although,
when properly handled, there is no subject better cal-
culated to lead the mind into a scientific groove.

We therefore cordially welcome this attempt to
indicate the lines which should be followed (or a pro-
fitable study of that portion of astronomy which deals
with the earth as a planet. The bald statmients as
to the earth's dimensions and movements, so frequently
appearing in the text-books ot gcograpln, furnish the
sole astronomical knowledge which many acquire ; but
they are, as Mr Gregory remaiks, quite inadequate.
I he de-ign ot the little book before U';, is first to
direct the students' attention to observations which
they may generally make tor themselves, and then to
show how such phenomena can be accounted for. Thus,

292

NA TURE

January 24, 1895

in the first chapter, a concise account is given of the
means of naming and identifying stars, suthcient to make
possible an intelligent observation of the diurnal motion
of the celestial sphere : and in the next chapter, it is
shown that the observations can be explained by regard-
ing the earth as a spinning globe. The same method is
followed throughout. ■ ,- • i

On the whole, the subject-matter has been judiciously
selected, but a slight want of proportion is shown in
introducing explanations of the phases of Mercury and
Venus, while those of the moon are not referred to at alK
The chapter on the determination of the size of the earth
would have been a little more educational if the descrip-
tion of the methods employed had been accompanied by
hints as to the amount of playground surveying which is
possible by the use of a protractor and foot-rule.

The book forms an admirable introduction to astro-
nomy, which stands a fair chance of fulfilling the author s
hope "that this little book will help to revive the obser-
vational astronomv of pre-telescopic times. This branch
of astronomical knowledge is certainly not without danger
of being neglected in favour of the fascinating and rapidly-
advancin- studv of the results obtained by the use of the
camera and spectroscope. The explanations are models
of clearness and accuracy, and the diagrams illustrating
them are excellent. Many of them are new, and involve
original ideas of the author ; as, for instance, a diagram
illustrating the sun's apparent path in winter and sum-
mer, and another showing the principle of Foucault s
pendulum by a lecture experiment. Teachers of
geography and physiography will do well to make
themselves familiar with Mr. Gregory's methods.

LETTERS TO THE EDITOR.

r The Editor does not hold himself responsible for opinions ex-
pressed by his correspondents. Ntither can he undertake
to return, or to correspond with the writers of, rejected
manuscripts intended for this or any other part of Nature.
No notice is taken of anonymous communications.]

The'Hodgkins Prizes.

The time for the reception of l realises or essays offered in
competition for the Hocigkins Fund Prizes of 10,000 Hols, of
2000 dols., and of 1000 dol«. respectively, clo-ed on Occcmber
31, 1894, and all papers so offered are now in the hands of the
Commiitee of Award.

In view of the very large numher of competitors, of the
delay which will be necessarily caused by the intended careful
exaroinaiim, and of the further lime which may be required to
consult a European Advisory Committee, if one be appointed,
it is announced that authors are now at liberty to publish these
treatises or essays without prejudice to their interest as com-
peti'ors. . S. P. Lanclev.

Washington, January 10.

The Artificial Spectrum Top.
As the spectrum top is exciting a good deal of interest at the
present m .ment. perhaps I may be allowed to record some
experiments which I have made with a view of arriving at a
solution of the colour problem which it sets. I have ol)scrvcd
the colours produced by the white light o\ the positive pole of
the electric arc, and also by monochromatic lijiht produced by
m»ans of my colour-patch appar.itus. The top was rotate! on
a horiitonlal axis at any desired speed by mean* of an clectrn-
m'.tor. The following colours were observed (No. I, No. 2,
No. 3, and No. 4 are the triple lines in order from the centre

of rotation) :

White light.

No. I. Crimson.
No. 2. Olive green.
No. 3. Grey ('lightly violet).
No. 4. Dark violet.
(When the yellow light of gas is used, the above results would
be m'idificd)

Ked(Clishl).
No. I. Red.
No. 2. Lighter red.
No. 3. Very light olive green.
No. 4. Darker olive green.

\

Green (.Magnesium />).

No. I. Bluish green.

No. 2. Lighter bluish-green.

No. 3. Same as No. 2.

No. 4. Ruddy black.

Blue {near the blue lithium).

No. I. Griiss green.
No. 2. Lighter grass green.
No. 3. Same as No. 2.
No. 4. Ruddy black.

Violet {all the violet of the spectrum).

No. I, 2, and 3. Light violet.
No. 4. Darker violet with a suspicion of red.
When a red a little below the red lithium line was employed,
all the groups appeared dark red, and as in the 3 sensation
theory this part and the violet are simple sensations, the results
obtained in these ia^t, were to be expected.

The next two series an- interesting, observations being made
in while light compounded by the mixture of two simple

colours. , , ■.,

Mixture of red and !^fen to make white.

No. I. Indigo-blue.
No. 2. Reddish orange.
No. 3. Same as No. 2.
No. 4. Dai ker orange.

.Wi.xlure of yellow and blue to wake white.

No. I. Sky blue.

No. 2. Sage green.

No. 3. Same as No. 2.

No. 4. Bluish-black (perhaps black).
These results were confirmed by an independent observer
When the lotalion was reversed the same order of olours was
observed, but in the reversed order. These observations seem
to confirm the original opinion I had formed regarding these
phenomena. , , , , ...

Hearing in mind that none of the observed colours in the
lines are pure colours, but mixed with a cert.iiii quantity ol
white and are seen on a more or less dark groun.l, ihen il the
order' of per>isiency of the three culour sensations be violei
(blue) urcen.red, the results would be as given .ibove. Should
Ihis be so the velociiy of rotation must alier the position of the
colours seen in white light, the violet being the last to be seen
on No. I when rotaied more rapidly, and this is the case. Ihe
effect of contrast also has to be taken into .iccount.

I have made a good many more .xperiments under varying
conditions of position and dimensions ol lines and proportions of
black to white; and it seems possible that this toy, when
modifte.l, may be adapted to give valuable inform.aimn as regards
certain problems in colour vision. W. i)K W. .XBNE^.

We have recently made a few experiments bearing on tlic
phcnomcna exhibited by Mr. C. E. Benham's artificial spectrum
ion (see NATURE, November 29, 184. P- I I3t. and the ex-
plknalion of them sug,;e.sied by Prol. Live.ng (Nature.
December 13, 1894, p. 167). and have .duained results which
we believe to be novel and of some scentihc inicrcst.

In ihe first place, if I'rof. I.iveing's expl.inanon he correct,
there seems to be no reason why the same ctfects should not be
obiained with broad bands ins.e.al of lines, the h"";>; '';";^:
diawn in precisely the same manner as the lines upon the white
half ol the disc. , ., ,. ■ .

It appeared to us of some importance to determine if this
were re.Mly Ihe case, as wc thought Ihe effects obl.iined with
Mr. Benham's top might po-sibly be due to ■'[•^■''">">" ''^^'''^
different in amount for the differeni col.mrs, whih- the c .ange n
colour with reversion indirection of rotation w.-,s p.esiimably due

,0 the black lines succeedinj;, upon a given p.iri of ihe reina, a
previously while ground in the one case and a previously bbck
one in the other.

NO 1317. VOL. 51]

January 24, 1895]

NA TURE

293

If this were so, by using broad bands instead of lines, one
would expect to get a coloured line at each border, while the
central portion remained uncoloured. Prof. Liveing's theory
would lead one to expect a uniformly coloured hand.

Accordingly, we prepared a disc, one half of which was
blackenel and the other half left white, as in Mr. Benham's
top, and on the white half were described three black circular
bands about one centimetre broad, with radii of about 47 and
10 centimetres respectively, and each with an arc of 45". The
outer band was described in an opposite sense to the two inner
bands, that is to say, in such a manner that if the disc was
routing so that the order of succession for the two inner bands
was black field, bands, while field, for the outer band it was
white, band.s, black. The disc was rotated by attaching it to
the spindle of an electromotor, the speed of which could be
graduated by friction against the spindle.

On rotating the disc at a slow speed, in such a direction that
the order of succession for the two inner bands was black, bands,
white, the following results were obtained : — The two inner
bands were each bounded on both inner and outer edges by a
bright red line, fading off towards the centre in a dark, some-
what reddish, ground, which became less coloured and darker as
it approached the centre. The outer band presented a marked
contrast to these two ; the whole e.xtent of the band itself was
black, entirely free from colour, but on the white ground on both
borders of the band, and apparently outside it, there appeared a
brilliant coloured band, varying in colour from blue to green. On
reversing the direction of rotation, the appearances w-re exactly
reversed ; the inner bands now became black bordered by green,
and the outer band reddish black lined by bright red.

We do not contend that this experiment proves that the efl'ect
is one of irradiation, for it might easily be supposed that the
heightened effect at the border is one of contrast with the
surrounding whiter coloured field. Our next experiment, on
the efl'ect of change in the speed of rotation, also tends to
negative the idea that the colours are due to irradiation, as there
is no reason to think that if irradiation were the cause, there
would be a change in colour with a change in the speed of
rotation, as was found to be the case.

To tot the effect of change in the speed of rotation, a disc of
one of Mr. Benham's tops was detached, fixed to the spindle of
the electromotor, and rotated in such a direction as to cause the
three cenlial bands to appear red with a slow speed of rotation.
On gradually increasing the speed, a remarkable series of
changes in appearance presented itself. The bright blood-red
of the three inner lines gradually grew darker and duller, and
then passing rapidly through a transition, the shades of which
we were unable to observe, gave place to a most vivid green,
which in turn, with still increasing speed, passed through
another transition stage into blue, deepening into a full violet
at the greatest speed we could obtain. On causing the motor to
slow down, the same changes in an inverse order from violet to
red were observed. These changes in colour unth the santc
direction of rotation are very remarkable, and seem to us to be
in direct opposition to Mr. Benham's explanation supplied with
the top ; for if the colours are due to a certain percentage of the
etherial vibrations being cut off, this percentage will remain the
same for all speeds, and there is no reason apparent why there
should be a change in colour with difference in speed. Neither
are they easily explainable on Prof. Liveing's theory that red is
the first colour to appear, and blue the last to disappear ; also,
the green we got at the intermediate rate was certainly not a
neutral grey or green, but a pure vivid green. Probably other
observers have not used a greater speed than that of the first
transition stage from red to green, which has a kind of neutral
green tint.

An experiment was next made with a disc constructed
similarly to that of Mr. Benham, but having white lines drawn
on the black semicircle instead of black lines on the while part.
On rotating this disc so that white lines on black ground suc-
ceeded the black surface, with slow rotation the colour obtained
was red, but a different kind of red to the deep blood-red given
by Mr. Benham's top in the case of i/ac/' lines on a s«/nVt' ground
also following a black surface, viz. a very bright red, evidently
not saturated. With higher speeds there followed a light green
and light blue, both evidently containing white. The diflerence
in hue of the two series of colours seems obviou-Iy that in the
case of the white-lined disc the colours are mixed with white,
and in that of the black-lined are mixed with hlack.

Throughout the series of experiments we have tried to eliminate

NO. I317. VOL. 51]

psychical errors as much as possible, by experimenting on
persons unacquainted with the expected results.

Belfast, January 15. J. M. Finnegan.

B. Moore.

The Kinetic Theory of Gases.

The difficulty of reconciling line spectra with the kinetic
theory of gases, has been referred to by Prof. Fitzgerald
(N.^TUKE, January 3, p. 221). The following considerations
show that it is possible under certain suppositions to have a
number of spectral rays with a very restricted number of degrees
of freedom. Most of us, I believe, now accept a definite
atomic charge of electricity, and if each charge is imagined to
be capable of moving along the surface of an atom, it would
represent two degrees of freedom. If a molecule is capable of
sending out a homogeneous vibration, it means that there must
be a definite position of equilibrium of the "electron." Jf
there are several such positions, the vibrations may take place
in several periods. Any one molecule may perform for a cer-
tain time a simple periodic oscillation about one position of
equilibrium, and owing to some impact the electron may be
knocked over into a new position. The vibrations under these
circumstances would not be quite homogeneous, but if the
electron oscillates about any one position sufficiently long to
perform a few thousand oscillations, we should hardly notice
the want of homogeneity. Each electron at a given time
would only send out vibrations which in our instruments would
appear as homogeneous. Each molecule could thus suc-
cessively give rise to a number of spectral rays, and at any one
time the electron in the different molecules would, by the laws
of probability, be distributed over all passible positions of
equilibrium, so that we should always see all the vibrations
which any one molecule of the gas is capable of sending out.
The probability of ao electron oscillating about one of its
positions of equilibrium need not be the same in all cases.
Hence a line may be weak not because the vibration has a
smaller amplitude, but because fewer molecules give rise to it.
The fact that the vibrations of a gas are not quite homogeneous,
is borne out by experiment. If impacts become more frequent
by increased pressure, we should expect from the above views
that the time during which an electron performs a certain
oscillation is shortened ; hence the line should widen, which is
the case. I have spoken, for the sake of simplicity, as if an
electron vibrating about one position of equilibrium could only
do so in one period. If the forces calleil into play, by a dis-
placement, depend on the direction of the displacement, there
would be two possible frequencies. If the surface is nearly
symmetrical, we ^hould have double lines.

The only weight I attach to these speculations lies in
illustration it affords that a number of spectral lines does
necessarily mean an equal number of degrees of freedom,
the existence of the "electron" I firmly believe; and
necessarily implies a very restricted number of variables

Arthur Schuster

the

not

In

this

"Acquired Characters."
It would appear that Prof. Lankester has not thought it worth
while to read all the letters that have appeared in Nature on
the question raised by Sir Edward Fry, unless it is to be inferred
from his remarks that he confines himself to the consideration
of ihe arguments of those who have a place on the scientific
Olympus of the Royal Society. In my letter, published
December 6, I defended Lamarck's laws against the accusation
that they were reciprocally destructive. Prof. Lankester
reiterates his accusation without any further support. But this
is not the whole question. In his last letter he suggests that
acquired characters corresponding to Mr. Gallon's definition
should be taken, and an investigation made as to whether they
are inherited or not in later generations. But in his former
lelter (November 29) he suggested very distinctly and deliberately
that such an investigation was unnecessary, because the question
was already settled. He has already condemned the heretic,
and now consents to his trial. His words were — " Since the old
character had not become fixed and congenital alter many
thousands of successive generations of individuals had developed
it in response to environment, but gave place to a new character
when new conditions' operated on an individual, why should
we suppose that the new character is likely to become fixed after
a much shorter time of responsive existence?" To apply this

294

NA TURE

[January 24, 1895

once more. o the ca-,e of pigment i"/''?,''°" '°„';,^^!j l^
thousands of generations no P'g™"^!^^'' ''""„^ffXP„ ^n j^'
on the lower side of a AaI fish, no light having lailen on it
The skris experimentally expose 1 to light and pigmen.
appeas- therefore the acquired character of absence ol pig-
m'^'nt! af.er thousands of generations, has produced no heredij^r
chanee, has not altered the potentialities of the tusue 1 he
„gament is fallacious because the question of how m-ch P'K^
"fntis entirely ignored, and also the question how long the
development of piiiment experimentally take,. 1 he l^"^" o'
The a^^ament is entirely on'.he other side. Assume in this
case, as Prof Linkester does in his general "g»l"-^?'' 'l";' ']>;
^ character, the absence of pigment, is an ^'^^'^^^.'^h/'"^^^/:
Then experiment has shown that this character is 'nherited
that is ?o say. the acti.n of light obviously overcomes a
resistance in producing pigment, and after years does not
produce as m'uch as Sn^L upper side is present from the
beginning. This resistance can be nothing eKe 'han here! ty
the inheritance of a tendency to pigmentlessness. Therefore
the acquired character is inherited. It is "";l«"'f [^;'^^;,"„
dispuilble that the argument propounded ^X P'of Lankes er
proves the inheritance of acquired characiers, if it is P'operly
applied in accordance with the facts. This is o" the -sumption
that the "old characters" are acquired. If they are no
Icqui red the argument has no force at all. The facts allow u.
foTy that the tendency to pigmentlessness or the resistance to
the development of pigment on the lower side » f:' Aounder is
certainly inherited, but whether or not it is due to the absence
of light during many successive generations we do "ot know^
As Sir Edward Fry says, if we by definition confine the term
"acquired characef- within the limits of an indivdua history,
then of course an acquired character can never be inherited. 1 he
qu"i°on is whether the conditions which produce a change in
?he individual can affect the offspring? The experimental
investigation must lake the following course Suppose a given
amount of stimulation X to act upon individuals "J^"««^ '^
generations, producing in the first generation a result ... 1 hen
fhe qiestio,^ is if X remains the same, does .v remain constant
or not? If there is no inherited effect then .v must remain
constant in all succeeding generations. If v '""eases l^ysom
amount, however small, and becomes x^a then a is no
acquired by the individual, but inherued, and it is clear that
the result will go on increasing to .. + 2.<, .. h3«..and so on to
, + „a, where n represents the number of generations In my
own opinion, there is evidence that something ol this kind does
occur, though definite investigations '''^■""^VrvviNrHAM
Plymouth, January It. J- T. CtNNlNGHAM.

As one who has been reading the discussion in your pages
on the meaning of the term "• acquire! characters, I may
perhaps be permitted to direct attention to the history of the
ierm It was first used with reference not to spec.es but to
individuals. Every character of an individuil is either derived
from the fecundated ovum or acquired during life. Ihis was
obvious; and the question arose: Could aciaired characters be
transmitted ? As long as the term is applied to an individual.
it has that kind of precision which is desirable in all scientihc
terminology, namely, that it perfectly explains itself.^

Glasgow, January 12. J"i"< Cleland.

Chinese Theories of the Origin of Amber.
In my letter on "Some Orienlal Beliefs about Uees and
Wasps "( N AT URK, vol. 1. p. 3°. May '». '^94). 1 have traced
the origin of the Chinese belief in the pioUction of amber
from bee, into the presence in amber of hymenoptorous remains.
Annarenlly developed from this belief, there is another mis-
conception recorded by Ch.ang II«.i (killed 300 A.D.), whose
Dajsaeeon ihe subject reads as follows : " In ' .>,hinsicn.chuin,
it iiwid, the re.ins of Ihe pine and arborvits, afier remaining
underground for one thousand year.,, are turned Mo lachyma
cMO! fKuh-linu),' which is turned into amber. Nolwilhstanding
thi. statement, the .Mount Tai produces Pachyma, but no
amber ; whereas Yungchang . . . produces amber, but no
P.achvroa. Another ihcry is that amber is made by burning
the honeycombs. Which i» true of these two theories is not yet

Of all Chinese theories propounded lo account for the origin

I Idtmifi'd thu» in Dr. K. IfV. " Nilion S.imbviiMi «hi." part vii
"I'uh.wuti-chl." lorn, iv., •lib. " V..i.wuh.

NO. I317. VOL. 51]

of amber, the most veracious one is given in Li Shi-Chi^ns
«,.rk» thus- " Amber originates in the resin of pines; when
ihe pines, with their bnanches and knots '">"";>"!'>• f°J"?;
were healed by the sun, the resin came out of the wood , it
co.i"uUied after days and sunk underground, and after under-
going subterraneous'changes. left behind the '-troussubstar.ee
[which is amber]. In this condition still it has in 1 tl e tenacity
Lf resin, so th.at when it is rubbed and wanned between the
palms, it can pick up particles of dust. Fhose '"^ects m '1^
enclo'ure had cohered with it before its sinking underground _^

Besides the resin of pines, ihe ^''"dat.o" ro.n the 1 ung

<,Uquidambar Maximo-vUzii) is asserted by Ivin T-'i-Sh'^g

lived in the tenth cenuiry .^.t-.) 10 be a nascent fonn of amb=r

the opinion well coinciding wi.h ihe Western idea that has given

to stvrax the name " Liquidambar. "

In "Shishwoh" (written in the fifth century .^.D.) amber
is said to be formed from the subterraneous metamorphosis ot
the gum of peach trees,'' which reminds us of the simile, Like
gum from the cherry," used by Pliny in his exposition of the
resinous origin of amber.' ,. /-^ r ■!,«„<.

Some other theories are full of absurdity. One of the e
holds that the dragon's blood buried underground turns to
amb^r, and the demon's to agate' Also, the etj^mologicaj
origin of " Hii peh," the Chinese name for amber, is .nvolved
in myth. In ancient times this word was written in two let.er ,
together signifying "Tiger's Soul," which is expl.a ned in this
wfy: "Arnightthe tiger applies its one eye for illainma Uon
and another for vision. When _ it is shot with arrow he light
of the eye, which is the tiger's soul, sinks underground and
mrns into a white slone Amber resembles this stone,

'^ Ac^ordingTo'" Ilwai-nan-tze " (written in the second centu^j
nc) " the dodder is the outgrowth of amber. Almost

inexplicable as this stnry may appear, I have found certain clue>
to its elucidation. Kau Y.i (lived in the second cen.ury A. D
Lives "Nu-lo" {i.e. Usuea hnghsimar _^% "" V T< <t-
" llsze '■ (.■ r. the dodder).'^ From this it is evident that the
early Chinese have confounded Usnea with dodder-.he con-
fusion caused by the superficial resemblance and simiUar habnal
of the two plants.- Now, .here is a Chinese belief record-l
about 240 n.c, that Fadiyma cocos is the root of dodder
which has doubtless grown out of the common occurrence upo
and under the pines of the L'snea am Pachyma. An -a-, h^.
I'achyma h.a.l been held as an mtermed.ary phase 'h ough 1 ch
resins were to pass into amber (see above), it would seeu tha

he story which affirms the dodder to be the "^'S'-^th ■«
amber, was not inconsistent with the understanding of the earl>

Chinese theorisers. Kumagusi; Minakai.v

January 11.

Rhynchodemus Terrestris in Germany.

Is NATUKKof October 25. 1894 (P- 617). Mr- Scha.11
mentioned Khynchodtmm tenalris, as stated in Germany, nea,
\\'uzburK. by Semper. It would seem that the worm w.v
exceedmRly r.are. But I found it repeatedly at several points ..,
S" .nyandThuringia. in the mountains and in the platn .,
leaved and fir wood, under moss or dead e.aves. Suffu.».n.
auen.ion would detect it without doubt m many region.
Recently Mr. Ehrmann found several specimens 'eeJ'ng on ■>
dead Arioit emfiriconim. 11. .->imku •

Leipzig.

The " Proceedings of the Chemical Society. "
TMK tille-page and index of this periodical h^^e j«t co.r
to hand. an,l on the liilc-pageoccur the words J-'l^^'L^^.
Secretaries." It appears 10 me right thal^uthors -should k„u^^

:i " Pan-liau K.'.og-muh," 1578, arl. " H.i-pih."

6 u'udon, " lincyclopx.li» of Plants." 1B80, p. 798.

7 " Na.ural Hi.ory," Engli.h iransLilion, liohn » edilion. ^o.. vi , p. 401.
"lw.li Chlnii-Shih. /o^. iiV- , .„,...

9 " l'.in.n.iu Kn.igmuti, I"'- "I- and arl. 11".

lUs^d";^':':; u'."rMivo,hi-, .n..^. in .he 5*.*„^»/.,<^*»

"li'ch'.nz Hwl appear, to have well distinBui-hcd ihc t«o plantf. Ha
„y,, •' if, "a ii.e^.1?pon ih. dodder, and ihc dodder ..p..n lrc«. P-h-

w.ih-chl," he. til.
11" I,ll.»lii Chi.nls.i'i, l(K. ill. text.

January 24, 1895J

NATURE

295

he precise significance of these words as lately determined by
he Council of the Sjciely.

Two courses appeared to be open : either to submit proofs
. the authors of the abstracts of their papers sent to the Society,
if any substantial {i.e. more than typographical) alteration had
been made ; in which case, the authors themselves would natu-
rally bear the responsibility of their statements ; or to thro* the
whole responsibility on the Editors, leaving them to make any
excisions or alleraiions they may choose in the abstracts sent to
them ; or indeed, if they so think fit, entirely to rewrite them.
The Council, in order to secure rapid ]iubIicalion, have chosen
the latter alternative ; and it should be understood that the
abstracts are now "official" — ie. the responsibility for all
statements put forth rests solely on the Editors of the
Proceedings. William Ramsay.

University College, London, W.C., January 14.

Philosophy and Natural Science.

Whilst feeling obliged to your reviewer's appreciation of
my essay (p. 220), I am bound to rectify some very glaring
discrepancies,

(1) As plainly stated in my pr.-face, my essay has «u/ obtained
the Philosophical Society's prize, but only an " honourable
recognition," and two fifths of the prize sum.

(2) Eighth line from bottom (p. 220), for " physical," read
" psychieal," as said in my paper (p. 30).

(3) Your reviewer makes me say : " Physical development is
not the cause, but the effect of psychical development " ;
whereas, I have expressedly combated this view of Wundt's

(P- 32)-

(4) Neilher did I say: " The modifications in the brain and
nervous system throughout the animal kingdom are intelli-
gii)le as resulting from psychical causes . . ." but only (p. 32)
that in many cases the beginnings of nndifications are intelligible
from the ps)chical side — e.g. the modifications of many organs —
resulting from sexual selection.

(5) Lastly, far from saying that the high mental position of
man, on the one hand, and of ants on the other, " is indepen-
dent of the structure of the nervous system," my sentence (p.
34) is: "Here, where the organic substratum (z'.c. the brain)
in both types differs even in its principal morphological features,
it is most evident how occult are the processes which constitute
the proper material side of psychical phenomena."

Freiburg, Badenia, January 5. David Wetteriian.

(i) The facts are that the Philosophical Society of Berlin
offered a prize of icoo marks for an essay on "The relation
of phdo.sophy to the empirical knowledge of nature."

'The essay reviewed, only obtained 400 marks of this prize,
and an honourable mention. In a hasty glance at the preface
1 overlooked the words " ein Antheil von vierhundert Mark,"
which occur in the next line to " der als Preis ausgesetzen
Summp," which caught my eye.

t2) This is evidently a slip of the pen, which I regret was
overlonked in proof.

(3) In my notes, jotted down as I read the pamphlet, I pu'
Wundt's words in quotation marks, intending to point out Mr.
Wetterhan's opposition thereto ; but in writing the review, I
unfortunately omitted the commas, and, I regret, entirely
misrepresented the author's views. Perhaps I may quote from
p. 32 of the jiamphlet : " Man durfte Wundt's Satz, ' dass die
phjsische Entwicklung nichl die Ursache, sondern vielmehr
die Wirkung der psychischen Entwicklung isi,' zu weitgehend,
und auch in seinen Konsequenz bedenklich finden." We are
then referred to page 46, where we reati ; " Der Ausfiihrung
dagegen, welche Wundt (s.o. p. 32) jenem Prinzipe gegeben
hat, vermag ich kaum eher beizustimmen, als der verwandten
Ideen Schopenhauer's."

(4) It appears to me that the passage will bear the construc-
tion which I put upon it ; though perhaps "throughout" the
animal series is too inclusive as a rendering of "der
Tierreihen."

(5) The author had been discussing the similarity of habits
and instincts in ants and termites, and then remarks that there
is a distinct .igreement in the mental functions (" von geistigen,
ja gcmiiilichen Kunkiionen ' ) of bees with those of the higher

NO. I317, VOL. 51]

animals. He refers to Darwin's opinion that the small brain of
a bee is a more wonderful thing than the brain of a Man : and
I think I was entitled to make the obviously true remark
that this "mental development is independent of the structure
of the nervous system." I was not quoting Mr. Wetterhan's
words, but giving the general sense of the passage.

In conclusion, I must express my regret that the condensation
of some of the author's remarks should have resulted in a con-
fused expression of his views. The Reviewkk.

SO!\fE EARLY TERRESTRIAL MAGNETIC
DISCOVERIES PERTAINING TO ENGLAND.

T T should be a source of considerable pride to British
^ men of science that so many of the discoveries in
terrestrial magnetism have been made in England. And
yet, owinc; to the absence of a complete and carefully
written history of the development of this science, pro-
bably few could enumerate all the achievements in this
subject by Englishmen.

In February 1893 the writer had the good fortune to
light upon a book,' by Will Whiston, containing matter
pertaining to the terrestrial magnetism of England, which
appears to have been entirely overlooked by prominent
terrestrial magneticians. Owing to pressure of work, this
interesting book, of which a copy was found in the Royal
Library of Berlin, could not be subjected to a critical
examination until the early part of 1894, when the writer
called the attention of prominent Berlin investigators,
such as Prof. Hellmann and Dr. Eschenhagen, to it.'- In
the meantime. Dr. W. Felgentraeger, Assistant at the
Gfittingen Magnetic Observatory, made an independent
discovery of W'histon's book, and carefully worked up
part of the mate/ial contained therein.' The writer has
since found time to complete his examination of Whiston's
contribution, and has embodied his results in a paper*
presented by Prof. Cleveland Abbe before the Philo-
sophical Society of Washington on November 10, 1S94.
In the following these results will be briefly sketched.

As will appear from the title of Whiston's work, the
chief object was the e.xposition of a method for deter-
mining the longitude and latitude by means of the
magnetic dip-needle, i.e. by means of the angle which a
magnetic needle mounted on a horizontal axis, when
placed in the vertical plane of passing through the
magnetic meridian, makes with the plane of the horizon.
It will be recalled that at that tiine great prizes had been
offered by the English Parliament for an easy and trust-
worthy method of determining longitude at sea. From
the very birth of terrestrial magnetism we find methods
proposed for determining longitude by means of mag-
netic observations, and, like the problem of perpetual
motion, these magnetic methods were revived every once
in a while until the beginning of the nineteenth century.
Owing to the irregular distribution of magnetism
within the earth's surface, and on account of the many
fluctuations terrestrial magnetism is subject to, these
magnetic attempts to determine geographical position
have been doomed to failure. They, nevertheless,
have done much to promote the science of terrestrial
magnetism. A striking instance of this is the book of
Whiston's. The prime object of the book has failed of

I "Th« Longitude and Latitude found by the Inclin.-itory or Dipping
Needle : wh. rem tlie l^vis of Magnetism arc also discnvcr'd. To which is
prefix'd an Hisloiicil Preface: and to wtiich is .subjcm'd Mr. Robert
Norman's New Attractive, or Account of the first Invrn-i n of the
Dipping Needle." By Will Whiston, M.A.. scmetime P'ofessor of
Maihciiiatifks in the Vniver«iiy of Cambridge. (London, 1731. 8vo, xxviii.
1 15, iv. and -ct pp a charts and 3 ctits.)

- Sec reina' ks in Physical Jin'ictv, vo'. ii. No. i, p. 72.

3 "Trie I^okline_r karie von Whist' ri und die jakuiare Aenderung der
magnetischcn Jiiklinaiion im n-ili«hfn Frplarrt." V\ n W Fe1g« ntineser.
Kepript from Nachrichtcu tier k Ccsclt. der It'iss. zu Ci^tliitgcn Math.
Phys. Klaisc, i?94. Nn. a. 8vo, ra pp.

■* Entitled *• The Earliest Isc clinics and Observations of Magnetic Force."
{liuii. J'hil. Stfc, U'ash.t vol. xii. pp. 397-410.)

296

NATURE

[January 24, 1895

its purpose,' yet the incidental discoveries, the import-
ance of which the author himself did not fully appreciate,
may perpetuate the name of Whiston for ever. It is most
remarkable that his contributions have been, apparently,
entirely overlooked.

Whiston, who, as stated in the title of his book, was
at one time Professor of Mathematics at Cambridge,
being Sir Isaac Newton's successor, was banished not
long after assuming the chair, on account of heresy —
he was a Unitarian. He was led to pursue the longitude
problem magnetically through Halley's famous Isogonic
Chart of 1700," which came under his notice. As is well
known, this chart of Halleys, giving the lines of equal
magnetic declination, i.e. these lines on the earth's
surface connecting all the places at which a magnetic
needle swung horizontally has the same bearing, is the
earliest published chart of its kind. In consequence,
these lines have likewise been termed the '■ Halleyan
Lines." Since then Halley's method has been efi'ectually
applied to the representation of other terrestrial pheno-
mena, £\i,'. distribution of temperature (" Humboldt's
Isotherms," 1817). Wilcke is credited as first applying
Halley's method to the representation of the distribution
of the magnetic inclinalion, and Wilcke's isoclinics are
therefore referred to occasionally as the " Wilckean
Lines." Wilcke published his chart, covering the greater
portion of the earth, in 1768." It appears, however, that
the credit of first drawing the isoclinics should be
accorded to Whiston. Wilcke nowhere states in the
article cited that he for the first time has drawn the
lines of equal magnetic inclination, and it is, moreover,
reasonable to suppose, by his reference to Whiston's
book, that he was familiar with its contents.

Whiston was led to drawing the isoclinics upon find-
ing that the " Halleyan Lines," through " the Quickness
of the Mutation of those Lines and their different Position
in the rest of the World," could not be satisfactorily used
for the determination of longitude. He therefore began
to consider the "lines of equal dip,"' thinking they
would answer his purpose better. To this end he col-
lected all observations of dip made up to his time, and
with their assistance drew, as far as then possible, the
"lines of equal dip" upon Mr. Molyneux's terrestrial
globe. Furthermore, to practically test his method,
he made dip observations himself in I7i9and 1720 in
various portions of England, and with their aid drew
and published the firsl isoclinics, to be sure for only a
small portion of the earth, viz. for southern England
and north-western France. These isoclinics were laid
down on two small charts {w\y. 182 cm.), and are
given opposite p. xxviii. of his book. The first chart is
the result of dip observations made in 17 19 with a
needle 12 inches long; the second '■' is based upon more
numerous observations made in 1720 with a 47J,-inch
needle. The results with the two needles differ, on the
average, by about i). , the long needle giving the larger
value. To counteract the error due to flexure of the long
needle, Whiston pl.iced a small " Poise of brass circular
Wire," whrch required shifting to and fro according to
dip, on the north end of the needle. Whiston believed
that the longer the needle, the better the result if the
needle be poised as stated. It is needless to say that
experience has not borne him out in this respect. Owing

* When Graham diwrivemd, a few yean afler the publication of Whiiton's
book. tltA* i^rr^ 'ri.l ina|{nctt*m ift Rubject to a daily variation, Wtitston
'if hi* method. See ** Meriioir*i of the Life and
11 WhiMon. Written by himwlf." (London, 1749,

lith'iitr.nphicatly in
• '1 tn '* N'cudriicke
' < ■ Kr(lm;4f[ncliitniliA."
\ f rier and Co.)

: .u ■ . Ic ParalIeK"

■I \>'. Keii[€n[rati;rr'^paper('M:c Ref. 3). Both
. factimjj?, in Hellniann'-i " Netidniclce," No.

Gr-

E'l

to the large discrepancy between the results of the two
needles, it might appear, then, that but little value can
be attached to these Whistonian isoclinics. The writer
finds, however, in his paper that the mean of the two
results can doubtless be accepted as being within i" of
the truth. Moreover, while the absolute value may be
impaired to the extent mentioned, the relative value
remains intact, as the elTect of the constant instrumental
error would be almost entirely eliminated when consider-
ing the relative distribution of the dip over England.
It is this latter fact that may give a value to these early
isoclinics. Thus in 1720, according to Whiston, the
isoclinics over England ran approximately from west-
north-west to east-south-east, while to-day they go
roughly from west-south-west to east-north-east. In the
accompanying sketch, the mean isoclinics are shown by
full lines for the epochs 1720, 1837, 1S60, and 1886, as
drawn by Dr. Felgentraeger in the paper cited.' It
will be seen that between 1720 to about 1S37 they shifted
from year to year, anti-clockiiiise ; they are now moving
clockwise. Sabine,'" I believe, was the first to call
attention to this reversal of motion. It is hoped that
this matter will receive further investigation.

ch.
4(.

NO. r;i

VOL.

51]

n'itttfr t'^ j;,uita/t if.

Whiston comes in, however, for a still ;4reater share in
the early terrestrial magnetic discoveries. He invents,
namely, a new and indirect method of determining the
dip — the vibration method. He swings a magnetic
needle horizontally, and determines the time of one
horizontal vibration. He then swings the same needle
mounted as a dip-needle, and again determines the time
of one vibration. From the two times of vibration it is
a simple matter to compute the ])rcvailing dip. Whiston
proposes this method as an approximate check upon the
direct method where the angle of dip is measured
at once. For example, Whiston found at London the
time of one horizontal vibration of his long needle 120'
from the magnetic meridian to be 60.} seconds, which
reduced to the magnetic meridian gives 426 seconds.
The time of one vibration of the same needle, mounted
as dip-needle, was found to be 22 seconds. If F is the
total magnetic force, we then have the following relation:
F : F cos Dip = (42-6)= : (22)'-, or Dip = 74° 32'.

Now, the mean of the results of the direct measure-
ments with the 1 2-inch needle (73? ), and of the 47l-inch

'<* /V(V. ffa^. Soc.t vol. xi. p. 144 : " The anjile of intersection of the
meridian and isoctinic* han been diminishing lip tn .iboiit 1840. when a rc-
vemal took place, .ind the nniile i^ now incrcasinc."

January 24, 1895]

NA TURE

297

needle (75^'), is 74^28'. Hence the agreement is quite
satisfactory. We can prob.ibly say that the magnetic
dip in r,ondon in 17200 was 74 5 ± 05 .

The invention of this new method of determining dip,
led to still more important results. In making the dip
observations with the long needle in 1720, for the pur-
pose of his second chart, he at the same lime observed
the time of one horizontal vibration of the same needle,
with the express purpose of determining the distribution
of the force. These vibration-times are tabulated on his
second chart." From them the distribution of relative
intensity can be determined. These observations of
Whision's are undoubtedly the earliest relative terrestrial
ma(;netic force observations ever tnade. It is usually
believed that the earliest relative intensity observations
are the defective ones of .Mallet (1769), or the more
successful ones, but lost in shipwreck, of Lamanon (17S5-
87). The abs >lute value of these Whistonian intensity
observations can, of course, not be checked ; however, the
relative value admits of some control. Thus the writer
in his paper has reduced the observations, taking the
value of the horizontal force at London as unity, and,
with the aid of the reduced values, has roughly sketched
the isodynamics (the broken lines in the figure)
as prevailing over southern England in 1720. It will
be seen that these lines of equal magnetic hori-
zontal force have the same general trend as the
isoclinics, as, indeed, they roughly should. Again, taking
two stations (London and Sallfleet), which are prac-
tically in the same meridian and are distant from
each other 2' in latitude, through which, consequently,
the same isodynamic would not be likely to pass, it is
found that the difference of the vibration-times — 6o| and
66 -seconds respectively, is in the right sense, i.e., since
the force varies inversely as the squares of the vibration-
times, the more northerly station, Saltfleet, gives the
smaller horizontal force, as it should. To be sure these
early intensity observations are affected with a large
probable error ; they may, however, not deserve to be
assigned to utter oblivion.

Upon the presentation of the writer's paper before the
Washington Philosophical Society, Prof. Abbe became
interested in the matter, and kindly called the author's
attention to a later book'- of Whiston's, a copy of which
was likewise found in the Royal Library of Berlin.
Whiston, in this book, gives an account of dip-observa-
tions made in various portions of the earth, with the aid
of most liberal means furnished by King George and
others, for the purpose of testing his magnetic method of
determining geographical position. He sent "four
several Dipping-Needles to Sea,'' and "with proper In-
structions to the Masters of the Vessels" to observe the
dip with both methods ''direct and indirect)," to discover
the State of Magnetism in the several parts of the
Globe." Thus Captain James Jolly set out in July, 1722,
for Archangel with one of Whiston's dipping-needles.
Owing to a defect of the instrument he could observe
only horizontal vibrations. Whiston says (p. 84), " he
made me twenty-eight very good Horizontal Observations
from the Latitude of 65 quite to Archangel." ... "In

!■ The only thing that Whiston says with respect to the method employed,
is the f -llowins Passage on page 112, viz : "The Difference of this. S7r,-«^r/:
of the Magnetick Power, from its Direction, is most visible in my Second .Map
hereto prelix'd. Where I have all ating set do%vn the * Seconds* wherein my
Needle pcrform'd a single h-jrizontal Vibration, at about 123 Degrees from
the M.ignetick Meridian, in most Places, whose Squares, when Allowance has
')ccn made for the different Obliquity of the several Directions as to our
Horizon, will give us the different Strength of that Magnelick Power at those
several Places ; .s does the angle of dip give us the different Direction of
the same power there. Now, at first .Sight, the former there appears to be
irregular, and the latter regular : as is the Case also of our Tcrella " Why
Whiston should have observed the vibration time iso' from the magnetic
merriiian, instead of across the magnetic meridian, the writer has not been
able to ascertain. Whiston does not appear to have made any further use
of his observations.

'- " The Calculation of Solar I-'clipses without Parallaxes .... with an
Account of some late Observations made with Dipping-Necdies. in order to
discover the Ixjngitude and I.atitude at Sea." (London, 1724.)

NO. 13 I 7, VOL. 51]

this Space the Needle altered its \'elocity very greatly,
as I expected it would : And 5 Vibrations which at first
were perform'd in about 280', beyond the North Cape,
came to 250 ; till towards .\rchangel it gradually returned
toabout 177"." Thefirst figure, 280", is probably a misprint,
andshouldbe 180". These ob.^er-i'ations are thefirst to sho-jo
the truth of the law that horizontal intensity decreases
in approaching the magnetic pole. Humboldt has
credited Lamanon (1785-S7) with the discovery of this
law ; it was not, however, firmly established until Hum-
boldt's observations of 1798-1803. Furthermore, Captain
Othniel Beal set out about the same time as Captain Jolly
for Boston. From thence he sailed to Barbados, and
thence to Charlestown, South Carolina. At all these
places and at sea he made dip observations with both
methods. A dip of 68' 22' is given for Bo-ton, and of
44^' for Barbados, on p. 92. These two dips precede by
ft/ty-eight years any dip tliat has hitherto become known
in the United States. The vibration-times are unfortun-
ately not given. A third dip instrument was sent with
Captain Tempest to Antigua and St. Christopher's, a
fourth sent with Captain Michel to Hamburg. The results
with the last two instruments had not yet been all received
at the writing of the book. Whiston does not give the
actual observations, but says, on p. 90, "The original
Journals are all in the Hands of my great Friend and
patron, .Samuel Molyneux, Esq., Secretary to his Royal
Highness the Prince of Wales, and Fellow of the Royal
Society : which Journals, when I have compleated the
rest of the Observations I hope to procure, I intend to
publish entire, for the more full Satisfaction of the
curious." It seems that Whiston never published these
records. It is hoped that the present article will induce
some one to look them up. They may possibly be a
valuable find.

In conclusion, let us sum up Whiston's achieve-
ments.

(i) Whiston drew the first isoclinics (1719-20).

(2) He invented the vibration method of determining
the dip.

(3) He made the first relative terrestrial magnetic
intensity observations (1720).

(4) The first intensity observations (1722), revealing
the law of decrease of horizontal terrestrial magnetic
force with approach towards magnetic pole, were made
under his instructions. L. A. Bauer.

THE TEACHING UNIVERSITY FOR LONDON.

"TOURING the last week very satisfactory progress
^-^ has been made towards the reorganisation of the
University of London as a teaching asw"ellas an examin-
ing body. In the first place. King's College has been
brought into line with the other teaching institutions of the
metropolis by expressing a general assent to the recom-
mendations of the Gresham Commission, coupled with
the proviso that any Statutory Commission appointed to
give effect to the Gresham Commissioners' recommenda-
tions should have power to make such modifications in
the scheme as may seem to them expedient after consulta-
tion wiih the bodies affected — a proviso already insisted
on by every teaching institution that has expressed its
general approval of the scheme.

The adhesion of King's College to the views of the
other teaching institutions mentioned in the Report of
the Gresham Commission, was made known on the eve
of the reception by Lord Rosebery of the deputation of
delegates from the London colleges, and made it pos-
sible for these to present their case with the strength
derived from complete accord.

On Tuesday last, Lord Rosebery received two deputa-
tions— one in the morning in favour of the Gresham
scheme, in which representatives of the Senate, the

29S

NATURE

[January 24, 1895

Annual Committee of Convocation, and the Committee
of Graduates of the University of London ; the Royal
Colleges of Physicians and Surgeons ; University Col-
lege ; King's College; Bedford College; the Medical
Schools ; the Theological Colleges ; and the Association
for Promoting a Professorial University for London took
part, and a second in the afternoon, composed solely of
members of Convocation opposed to the scheme.

Lord Rosebery's replies show that personally he is
anxious to give effect to the Commissioners' recommen-
dations. To the first deputation he said that the Govern-
ment attach great importance to the Report of the
Commission, and are fully sensible of the fact that the
present time seems to offer a favourable opportunity, and
one that ought not to be postponed, for the appointment
of a Statutory Commission in the sense desired by those
who had addressed him ; while to the second, he made it
clear that the opinions of the Government point in the
direction of the appointment of a Statutory Commission,
which would be able to receive full representations from
any interests involved, and thereby be enabled to arrive
at a scheme not unsatisfactory both to the present
University and to the Empire at large.

Lastly, on Tuesday evening. Convocation of the
University of London met, and for the first time came
face to face with the question of approval or disapproval
of the Commissioners' recommendations. As pointed
out in a previous article (vol. I. p. 269), the power of veto
possessed by Convocation under the Ch.irter lent con-
siderable importance to the decision arrived at, since an
adverse vote might seriously retard the reorganisation
of the existing University. In view of this contingency,
it is highly satisfactory to record that Convocation, the
last of the bodies to which the scheme has been sub-
mitted, by 1 57 votes to 133 resolved — " That Convocation,
while desiring to express generally its approval of the
proposals contained in the Report of the Royal Commis-
sion, is of opinion that power ought to be given to the
Statutory Commission to vary the details of the scheme,
and that it ought to be made an instruction to the Com-
missioners, before framing the statutes and regulations,
to confer with duly accredited representatives of the
Senate and of Convocation as to the modifications which
may be desirable ; " a previous resolution affirming that
there should be one University in London, and not two,
being carried by a slightly larger majority, namely, 206
votes to 175. These majorities may not be large, but
they may be fairly taken to proportionately represent the
opinion of the 3600 members of Convocation, since so
far as any expression of opinion has been elicited by the
various parties, 1165 members have expressed general
approval of the Commissioners' recommendations, while
900 have indicated that in their view any teaching Univer-
sity for London ought to be constituted apart from the
existing University. It may be earnestly hoped that with
this vote the long controversy within the University has
come to an end, and that all parties will now unite in the
endeavour to make the new University worihyof the
capital of the Empire. \V. Pai.mek Wynne.

NOTES.

We are informed that Mr. G. F. Scott Elliot has arrived at
Illanlyrc, in the Shin' Highland*, on his way home. His route
from Ruwenzori has Ixen by Karagwe and Urundl, to the
extieme north of Tanganyika, which was travcr.'ied in Arab
dhowi to Abcrcorn. Thence he followed the usual route by
the Stevenson Roid to Lake Nyoua and the Upper Shird-.

Prop. E. WARnuKO, Profesior of Physics in Freiburg
Univer-ily, has been appointed Prof. Kundt's successor in
Berlin University.

NO. 1317. VOL. 51]

M. Hautefeuille, Professor of Mineralogy at the Sor-
bonne, has been elected a member of the Section de Minera-
logie of the Paris Academy of Sciences.

Dr. S. Nawaschin has been appointed Professor of Botany
and Director of the Botanic Garden at Kiew, Russia.

The death is recorded, at Berne, on December 13, of Dr. F.
A, Fliickiger, well known for liis researches in pharmacologica
botany, at the age of sixty-six.

Dr. Murray Thomson died on the 13th inst., in his sixty-
first ye.ir. He was a Fellow of the R0y.1l Society of Edinburgh
and a Fellow of the University of CilcuUa. For some years
he was Professor of Experimental Science in the Government
Engineering College, Roorkee, and chemical examiner for the
Government in the North-Western Provinces of India. He
was also the author of several medical and chemical treatises.

The 7»«« correspondent at Teheran reports that the town
of Kuchan, which was destroyed by an earthquake fourteen
months ago, and immediately rebuilt, was again destroyed on
January 17. The extent of the damage and the loss of life
are not yet known. Earthquake .-.hocks were also felt at
Meshed, but no damage was done.

We learn that a general survey of the tiles and currents on
the Canadian coasts is now being commenced by the Canadian
Department of Marine and Fisheries. It cannot fail to be of
great use to navigation, and of especial interest lo science, as the
districts will include the phenomenal one of the Bay of Fundy
with its 70 feet rise of tide, with which we have nothing to
compare in magnitude iii the British Isles.

The Konigllche Gesellschaft der Wissenschafien of Gii'.tingen
are organising a conference of delegates of scientific societies
and academies, for the consideration of the relations between
the variations in the intensity of gravity and the geological
constitution of the earth's crust. It is intended that the con-
gress shall take place at Innsbriick on September 5, where
and when the International Geodetic .Association will hold a
meeting.

The first number of the new series of Stieiice has now
reached us. To the editorial committee announced in our
issue of December 20, should be added President T. C. Menden-
hall of the Worcester Polytechnic Institute (Physics), Prof.
R. H. Thurston of Cornell University (Engineering), Prof
Le Conle of the University of California (Geol )gy), and Prof.
H. F. Giborn of Columbia College (Gener.-il Biology). The
editorial committee, composed of the American men of science
best known in England, and the contents of the first number,
promise a journal that will adequately represent the progress
of science in America. If in a multitude of counsellors there
is wisdom, the j mrnal .should greatly .idvance scientific know-
ledge ; not, however, by publishing memoirs and papers for
specialists, but by promoting intercourse between students of
all branches of nature.

On Friday, the nth inst., the Physical Society of London,
in response to an invitation from Prof Carey FoUer, visited
the new physical laboratories of University College. Before
the commencement of the regular meeting in the lecture theatre
(a repoit of which will be found in another column), the large
number of members present went over the laboratories and
practical class-rooms. There are three large rooms solidly built
on the ground, and devoted to the use of the more advanced
students, and of those cngiiged in original research. They arc
in a separate building apart from the main structure, and were
specially built for physical work. Above one of them is the
optical ro5m, while within the main ^building there are two

January 24, 1895]

NA TURE

299

large basement rooms, one used chiefly for electrical and mag-
netic measurements, and one reserved for the practical classes.
On the floor above are the lecture theatre and smaller class-
room, apparatus room, chemical room, &c. The laboratories
are lighted in the main with electric light, the direct current,
supplied by the St. Pancras Vestry, being also used to charge a
set of about fifty accumulators. A collection of apparatus was
on view, more especially that designed for educational experi
ments, and used by students in the practical classes. Some of
the pieces shown were of historical interest, among them being
various instruments designed and used by Ritchie, who was
formerly Professor of Natural Philosophy in the College.

On Thursday last, January 17, the French Society of Aerial
Navigation inaugurated the lectures to be delivered to the
pupils of the newly-established school of aeronautics. During
an address, Prof. Cornu, who was in the chair, said that he was
glad that the .-Vcademy of Sciences had always exhibited an
interest in aerial navigation. In 1782, a programme was drawn
up of experiments to be conducted with the help of balloons.
In 1794, there was established at Meudon the first aeronautical
school, and the first captive balloons were made. In 1802,
Gay-Lussac and Biot made the first scientific ascents, which re-
mained almost unequalled until sixty years afterwards, when
Glaisher took his aerial travels. The first dirigible balloon was
constructed in 1870. Later, Paul Bert investigated the condi-
tion of human life at high aUitudes. With these lacts before
them, the pupils of the French aeronautical school were re-
minded that their efforts would always be supported by the
Academy. Aeronautics had been always popular in France,
and had rendered good services to science and to the country.

Some forgotten pages of photographic history were brought
before the Brixton Camera Club, by Mr. W. H. Harrison, on
January 15. It was pointed out that the many photographic
researches of Foucault have been so completely overlook ed that
in scarcely any recent photographic history is mention to be
found of more than his name, if so much as that. Fouc.auh's
early experiments in photographing the spectrum upon daguer-
reotype plates are interesting, and his results were not com-
plicated by the presence of collodion, gelatine, or other col-
loids. In those early days photographers were so anxious to
improve processes and to quicken them for purposes of por-
traiture, that perhaps these researches in the higher branches of
photography inierested them little, and soon afterwards were
forgotten entirely, so that the name of Foucault as a pioneer of
photography has practically passed out of the literature of the
subject for nearly a generation. H. liiyard, the first to exhibit
a selection of photographs to the general public, in July 1839,
hasalso been much neglected in modern photographic literature.
By means of his process, direct positives could be obtained
without the intervention of a negative. Bayard's process seems
Ukely to initiate useful modifications at the present time, in the
easy production of reversed negatives. Sometimes it is now
facetiously said that ihe best place for backings to prevent halation
is on the front of the plate, meaning the use of a thick coating
of emulsion : perhaps on Bayard's principle something of the
kind may hereafter be done in a more literal sense. It should
be remembered that there are two kinds of halation, and that
one of them is due to reflection among the panicles of silver
haloid in the film itself. Perhaps something of especial benefit
in astronomical photography may hereafter be evolved from
Bayard's principle. Who knows but that it may hereafter lead
to the production of a new class of dry plates which can be
freely exposed to light, and, when required lor use, sensitised by
an alcoholic or other volatile liquid containing a haloid salt, to
enable the re-drying to be elTected quickly ?

NO. 1317, VOL. 51]

Dr. a. MacDonald, of the U.S. Bureau of Education, has
sent us a number of statistics, showing the sensibility to pain,
by pressure, in hands of individuals of diflferent classes, sexes,
and nationalities. So far as they go, the results indicate that
the majority of people are more sensitive to pain in their left
hand than in the right. Women appear to be more sensitive
to pain than men, but of course it does not necessarily follow
that women cannot endure more pain than men. American
professional men are more sensitive to pain than American
business men, and also than English or German professional
men. The labouring cl.asses are much less sensitive to pain than
the non-labouring classes, and the women of the lower classes
are much less sensiiive to pain than those of the better classes.
The general conclusion is that the more developed the nervous
system, the more sensitive it is to pain. It is worth remark
that, while the thickness of tissue on the hand has some
influence, it has by no means so much as one might suppose,
a priori; for many with thin hands require much pressure
before experiencing any pain.

An auriferous quartz-vein has been met with near Douglas
in the Isle of Man. This seems to be the first recorded dis-
covery of gold in that island, though, in view of its presence in
the very similar districts of Merioneth and Wicklow, it is not
in any way surprising.

Electrical Discovery is the title of a new fortnightly journal,
in which it is intended to publish information on electrical
patents filed in the British Patent Office. The Official Journal
famishes short abstracts of such inventions, but these do not
appear until after the period for opposing the grants of the
patents has expired. The new journal is designed to supply
the need, by giving electricians early abstracts of all patent
specifications and amendments relating to electricity. Digests
and reports of patent cases of interest to electricians will also
be included, and an index of articles on electrical subjects.

A FEW years ago it was practicable for persons of moderate
income to subscribe to all the periodicals devoted to engineering
and allied sciences, and to keep abreast with the contents.
Now the number of such journals is^ so great, and so many are
the memoirs and works bearing on engineering, that engineers,
like the rest of ui, are feeling the need of an index of their
literature. Suggestions for the construction of such an index
are given by Prof. G. D. Siephardson in the Transactions of
the American Institute of Electrical Engineers for November
1894, and the following number contains a report of a long
discussion on the subject. It is a satisfactory sign of the
development of the scientific side of engineering, that
electrical, mechanical, hydraulic, civil, and mining engineers
want an index to their literature.

The great Andalusian earthquake of December 25, 1S84, as
is now well known, produced slight disturbances of the mag-
netic curves at Lisbon, Pare St. Maur, Greenwich, and
Wilhelmshaven. Two astronomical clocks were also stopped
at the observatory of San Fernando, near Cadiz. From the
times so recorded, the French Commission appointed to study
the earthquake obtained values which seemed to show that the
velocity of the earthquake wave diminished as it radiated out-
wards. In two recent papers (A'. AccaJ. dei Lined, Rend.
iii. 1894, pp. 303-310. 3'7-325). l^r. G. Agamennone recon-
siders the problem. He shows that the apparent diminution of
velocity would disappear if the time at Cadiz were a minute too
late. And an error of this kind, he remarks, is possible, for
the times given for the magnetic observatories correspond to the
beginning of the movement, whereas the clocks .-it Cadiz would
be stopped during a later phase. Assuming the velocity uniform,

300

NA TURE

[January 24, 1895

he finds it to be 315 ± '19 kilometres per second, a value which
agrees very closely with some recent determinations.

The light of the Blue Grotto of Capri, as well as that of the
so-called red and green grottoes (^otlo rosso and ^otto vtrle)
has been spectroscopically tested by Dr. 11. W. Vogel, and is
described in the current number of IVitJeinann's Annalen.
The most striking fact abnut the Blue Grotto was the occur-
rence of an absorption band between the Fraunhofer lines C
and E of the solar spectrum, which does not occur in ordinary
water. Inaddiiion to this, the red and the orange were fxtin-
guished as far as the D line. The same spsctrum was exhibited
by the water in front of the grotto. The "green grotto " is a
rocky tunnel filled with bluish-green sea-water. The rocky
walls show green reflections in the interior, produced by the
impact of the bluish light from the water upon the yellow stones.
But the absorption band noted in the Blue Grotto is here en-
tirely absent. From the top of the cliffs, patches of azure-blue
water could be seen surrounded by green. They all showed the
absorption band, and retained their position permanently, so that
they are probably due to some local cause. The " red grotto "
does not show a trace of red liijht.

Attention was recently drawn in our columns to an interest-
ing observation made by Dr. Ostroumoff, of Sebastopol, on the
power possessed by the Copepod Ponlellina mediurranea, of
jumping in the air upon the surface film of water. It appears
from several further communications that this peculiar habit is
also possessed by several other Copepods, viz. Pontellaatlantica
(M. Edw.), according to Dahl(f-Vry4. deiitsch. Zool. Gesclt. 1S94,
p. 64), and Pontilla semrifer {^taiy), according to an observa-
tion made by Captain Hendorff, who stales that he several times
saw this Copepod leap qui'e a foot high from the water in which
it was contained. Herr Mrazek, in recording Captain HendorfTs
observations (Zool. Anz. No. 415, p. 5), also men'ions the
additional case of a Schizopod having the same habits. This
phenomenon, however, can be easily observed in the case of
British Schizopods, and appears to be the result of abnormal
conditions rither than a natural habit. Herr Mr.-izek does not
support Dr. Ostroumo ff in his view of the connection between
this habit and the process of exuviation ; he regards the move-
ments in question a^ either purposeless and sportive, or for the
sake of effecting escape from enemies. The latter view
certainly receives support from the somewhat analogous case of
the flying fish.

We have received an elaborate paper read before the Con-
gress of Scandinavian Naturalists at Copenhagen, by Dr.
Ernst Abery, on the transmission of yellow fever. Much
uncertainty and difference of opinion exist as to the means by
which thi« disease is distributed, some authorities asserting that
it has a purely local malarial origin, and cannot be imported
into a place ; whilst others are equally convinced that it can be
imported, but is not transmissible directly from one individual
to another. Dr. Abery, whj has made a special study ol the
subject, has gathered together the principal facts about the
dissemination of yellow fever, which are admitted by various
authorities, and seek* to connect them together and explain
them by a theory of his own. He accepts for this purpose the
presence of a particular microbe specific to yellow fever, and
regards it as capable of existing in different forms, such as spores
and rodlets, and endowed with correspondingly different charac-
ters and degrees of virulence. By means of this theory, Dr.
Abery explains many otherwise puzzling phenomena, and has
produced an excellent working hypothesis. Unfurtuoalely,
however, it must remain only a hypothesis, lor so far no microbe
ipecific to yellow fever his been discovered and accepted ; but
possibly the author inteods attacking this aspect of the question
next.

NO. 13 I 7. VOL. 51I

The new volume of Memoirs (Zapiski) of the Caucasian
Geographical Society (vol. xvi.) is again one of exceptional in-
to est. It contains, first, a series of botanical papers on the
rtnra of Northern Caucasia, by I. Akinfieff, together with an
account of a journey of the same author in Ossetia and Svanetia ;
three papers, by N. M. Alboff, on the vegetation of Western
Transcaucasia, on new species found in Abkhasia, and on the
Abkhasian ferns ; and an abridged translation of several papers,
by Dr. E. Dieck, on the flora of Western Transcaucasia ; the
series thus making a very valu.ible addition to our present
knowledge of the flora of Caucasus. And next, the same
volume contains a series of papers devoted to the still imper-
fectly known parts of the central section of the Main Caucasus
ridge. M. N. Zhukoff contributes a paper on the glaciers of
North-east Svanetia, with a new and very interesting map
(i 3 miles to the inch) of a wide glacier region ; A. V. Pastuk-
lioff describes his ascensions of the Shah dagh and the Ararat,
as well as his visits to some of the high-level villaL;es, of which
Kurush, situated at a height of 8175 feet, is the highest in
Caucasia — the paper being accompanied by small maps and
photographs of the Kichendagh, the Nesen-dagh, and the
Kurush village ; M. and Mme. Rossikoff contribute two papers
on the glaciers and Alpine lakes of the Central Caucasus
main chain, giving exact measurements of the speed of
motion of several glaciers ; and another Alpinist, N. Dinnik,
gives a description of Mount Oshten and the surrounding parts
of the province of Kuban, which is full of very interesting
gengraphical and botanical data. And, finally, two papers, by
MM. Shalikoff and Andronikoff, are geographical and statistical
descriptions of two districts of the government of Tiflls — Ksan
and Uraveli. An index of all the papers contained in the
hitherto published volumes of both the .I/f/ai'/ri (Zapiski) and
the Bulletin (Izvestia) of the Caucasian Geographical Society,
is also a most welcome feature of the present volume.

A SECOND edition of Dr. G. V. Poore's instructive " Essays
on Rural Hygiene" has been published by Messrs. Longmans,
Green, and Co. The new edition includes more than fifty
additional pages.

The Rose Polytechnic Institute, Terre Haute, Indiana, has
published a bulletin on "Physical Units," by Prof. Thomas
Gray. The bulletin comprises a concise and admirable col-
lection of definitions of fundamental and derived units.

No. 2 of the Bolanisclies Cenlralblalt for 1S95 contains an
exhaustive bibliography of the colouring matters of plant?, by
Dr. Hermann Ritter Schroiter-Kristelli, together with some
new observations on the occurrence of carotin.

A WORK entitled " Molecules and the Molecular Theory of
Matter," by .\. D. Risteen, will be published in February by
Messrs. Ginn and Co. The work is intended to be a pri|iular
exposition of the molecular theory of matter as it is held by
the leading physicists of to-day. The subject is treated from
a physical standpoint.

When a book twenty years of age blossoms into a second
edition, it is hardly necessary to say that the original must
have undergone a thorough revision. This is the case with
Prof. Alfred Newton's little " Zoology," published in 1S74,
among a series of manuals of elementary science, by the
Society for Promoting Christian Knowledge. The new
edition takes in much of the zoological work done during the
past two decades, thus rendering it one ol the cheapest,
handiest, and best broad introductions to the study of zoology

The publication is announced of the first number of a
Pliy(ollieca/l»reali-ameri((tna,\hy Messrs. F. S. Collins and Isaac
Holdcn and Dr. W. A. Sctchcll. The work will include all
families of Alga:, both freshwater and marine (except, for the

January 24, 1895]

NATURE

\o\

present, Characese, Desmidieae, and Diatomaceae), from the
Arctic Ocean to the Isthmui of Panama, including the West
Indies. Each number will include fifty species, and the price
will be five dollars. Subscriptions and offers of con'.ributions are
to be addressed to Mr. Frank S. Collins, 97 Dexter Street,
Mass., U.S.A.

Fro.m a note in the Botanical Gazette we learn that the fo.t-
tail grass or sriuirrel-tail grass, Hordeitvi itibatum, is a serious
pest to stock in the Western States of America. The barbed
awns break up into pieces, penetrate the gums, especially near
the teeth, producing swelling, and ultimately suppuration, of the
gums, and ulceration of the jawbones and leeth, the latter being
so loosened as to drop out. If the animal continues to eat hay
containing this grass, the disease progresses till the bony tissue
of the jaws is disarranged, the ulcers extend to all parts of the
jaw bone, and it becomes distorted and enlarged. The marrow-
filled interior is changed into great cavities filled with the
broken awns. This condition may continue till the cavities
extend entirely through the jaw, and the tightly-packed awns
protrude till they maybe pulled out with forceps or fingers.

The completeness of the series of Eocene and Cretaceous
strata exposed along the great central river system o'' Alabama,
is well known to American geologists. A report on the geology
of the coastal plain of Alabama, just issued by the Geological
Survey of that State, shows that, on account of the fine exposures
along the river banks, and the great number and perfection of
the fossils, the region presents the most complete and varied
series of Eocene and Cretaceous strata known in the United
States. All that relates to Cretaceous, Tertiary, and Post-
Tertiary formations in the vicinity of the Alabama and Tom-
bigbee rivers, is described in the first part of the report. The
second part contains all the data of practical value concerning
the various phosphatic marls, greensands, &c., occurring in the
region surveyed, and the third part includes a number of geo
logical details referring to the different counties of the State.
Prof. E. A. Smith, the State Geologist, and those who have
assisted him, may be congratulated upon the publication of this
important account of the stratigraphy of the Cretaceous and
Tertiary formations of the Gulf region of Alabama.

An inorganic mode of preparing hydrazine, NjHj, is de-
scribed by Dr. Duden, of the Jena University Laboratory, in the
latest issue of the Berichte. Hitherto the numerous methods of
formation of this important hydride of nitrogen, described by its
discoverer. Prof. Curlius, and his assistants, and by Thiele
and von Pechmann, have all been based upon the decom-
position of more or less unstable organic compounds of
the diazo, nitrosamine, or nitramine types. Dr. Duden has
succeeded in an inorganic synthesis by use of a singular
compound, discovered by Davy and further investigated by
Raschig and by Divers and Haga, which is produced by the
action of sulphurous acid upon potassium nitrite. This
compound, whose composition is represented by the formula
KjSOj . N.,Oj, is now found to yield hydrazine upon careful
reduction in alkaline solution. Divers and Haga showed
that the ordinary products of reduction of the compound with
sodium amalgam in concentrated alkaline solution are mainly
potassium hyponitrite IvNO and hydrogen potassium sulphite
HKSO3, smaller quantities of hydroxylamine and ammonia
being likewise produced. Dr. Duden finds that if the reduction
with sodium amalgam, or zinc dust and ammonia or soda, is
carried out at a low temperature, the solution produced
possesses very strong reducing properties, and after acidification
deposits the salt of hydrazine corresponding to the acid em-
ployed. The freshly prepared compound of potassium sulphite
NO. 1317, VOL. 51]

and nitric oxide is suspended in water cooled by ice, and sodium
amalgam is gradually added with further extraneous cooling hy
means of a freezing mixture, until the liquid is found to strongly
reduce Fehling's solution and yields, after acidification and
warming to expel sulphur dioxide, a precipitate of benzalazine
upon the addition of benzaldehyde. The benzalazine so ob-
tained is found to exhibit all the properties of the compound as
described by Prof. Curtius ; it melts at 93'' and yields numbers
on analysis exactly agreeing with the formula (CcH.-,CHN)„.
With sulphuric acid it yields hydrazine sulphate (N„H4).> . H.SOj,
identical in melting point (256') and all other properties with
that derived from the organic methods of preparation. The
formation of hydrazine from the compound of nitric oxide and
potassium sulphite would appear to occur in two stages, an
intermediate reduction compound being first produced of
analogous constitution to Davy's salt in accordance with ihe
following equation :

^KO/^ • ^^ ^ ^" = ^^^'\V, . NH„ -f H„0 -1- KOH.

A further reaction then occurs between the intermediate com-
pound and the alkali, with production of potassium sulphate and
hydrazine

^5°3\n . NHj + KOH = K.,SOj + HoN . NH..

The additions to the Zoological Society's Gardensduring the
past week include a .Macaque Monkey (Mataciis cynomolgus, 9 )
from India, presented by Mr. H. Ralls ; a Black-backed
Jackal {Canis niesomelas) from South Africa, presented by
Mr. Fred Bissmire ; a Dusty Ichneumon {flerfestes pulveru-
lentits), a White-throated Monitor ( / 'aranus albigularis) from
South Africa, presented by Mr. J. E. Matcham ; a Derbian
Wallaby (Halmatitrus dcrliianus) from Australia, presented by
Mr. Joseph Palmer ; a Jackal Buzzard {Biitco Jacal) from South
Africa, presented by Mr. E. Wingate ; a Yellow-headed Conure
(Coiiurus jendaya) from Southeast Brazil, a Biown-throated
Conure {Conttrus icniginosiis) from South America, presented
by Mrs. Hankey ; three Eroded Cinixys (Cinixys erosa), two
Home's C\n\\ys (Cinixys homeana) from West Africa, presented
by Mr. J. Banks Elliot ; a Lesueur's Water Lizard (Physigna-
thus lesueuri) from Australia, deposited ; a Rosy-billed Duck
{Metopiana peposaca), a Garden's Night Heron {Nycticorax
gardeni) from South America, purchased.

OUR ASTRONOMICAL COLUMN.

The Perseid Meteors. — This well-known shower of
meteors should be of the greatest interest to the mathematician,
as well as to Ihe observer. At Pulkova, in 1S93, the shower
was observed from Juh 22 to September 12, and a discussion of
the 563 paths recorded forms the subject of an interesting paper
by Dr. Bredichin (Bull. Imp. Acad. Sc, St. Petersburg,
September 1894). It has long been known that the Perseids
are not as other regularly recurring meteor showers, and Dr.
Bredichin explains their peculiarities by supposing that they are
not produced by a swarm of meteorites, in the true sense of the
word, but by particles circulating in difl'erent orbits. These
orbits have widely differing inclinations, and the other elements
also show striking departures from each other. One gets a good
idea of the system which is suggested, by imagining a bundle of
materialised orbits crossing the earth's orbit at the points which
the earth occupies during August, and for some days before
and after. The particles with long periods correspond to the
meteors at the beginning of the showers, and to the primitive
position of the comet from which the meteors are supposed to be
derived, which, having a moderate period, has left these meteors
behind. The position of the node of the comet is not symme-
trical with reference to the nodes of the meteors, but appears to
be nearer the beginning than -the end of the showers. This con-

;o2

NA TURE

[January 24, 189;

tioaity of ihe phenomeoa for so long a time seems to confirm the
idea of a variety of periods for the particles, and indicate also
the repeated omission of the meteors from the body of the
comet. If the forces of disruption were only those which have
ordinarily been considered, the meteirs would be dispersed in a
long thin stream along the length of the orbit, as in the case
of the November meteors ; but since Ihe orbits of the meteors
are variously inclined lo that of the comet, another force, acting
transversely to the plane of the orbit, must be admitted as an
important factor. The anomalous phenomena of the tails of
some comet-i — a subject with which Dr. Bredichin is already
closely associa'ed-and the energetic emis-ions which have been
noted in several comets, includmt; that which is connected with
the Perseids, serve to demonstrate the possibility of such an
action as that which he supposes to have taken place in the case
of this swarm.

Comet 189+ I (Denning) and Brorsen's Co.met.— Dr.
Hind cmlributes to Ihe current number of the Aslronomische
XaehrichUn (No. 3271) a very inieroting note as to the identity
of Denning's comet with that discoveied by Brorsen. To
investigate the question, he has found, with M. Schulhof's
elements for Denning's comet and Dr. Lamp's elements for
Brorsen's comet, that the distance of the orbits would be
00367 in Longitude 285' (1894 'o), and that in April 18S1 the
comets approached one another within a distance of 0.1 38.
On Ibis account, he says, during Ihe comet's recession from
perihelion, might rot Brorsen's comet have met with a cata-
strophe, causing disintegration and the return of a portion of it
to perihelion, in a somewhat different orbit, in Denning's comet
of last year ?

Dr. E. Lamp has also considered this question of identity,
and, in referring lo Dr. Hind's note, writes that the similarity
of the two orbits is very striking, and that, in the beginning of
1881, the two bodies must have been very close lo one another
near the point of intersec'ion of the two orbits. With the same
elements as used by Dr. Hind, he finds the point of intersection
of the orbits in Longitude 28+ 47' and South Latitude t 57'.
The places of the two bodies are then as follows : — ^

True anomaly
Ecc. anomaly
Radius vector

Oenntog.

154 21
123 22
5-240

169 7
147 25

5'2i8

The point of nearest approach in the orbit of Denning's comet
occurs ill a position 5' behind, and in Ihe Brorsen's orbit 4'
before, the aclual place, the distance between these points being
o°022 radii of the earth's orbit. Dr. Lamp suggests that, by
decreasing Scliulhol's value of the mean daily motion by about
28', the comets would Ihus be brought together. The question,
however, is in a very undecided state, but .astronomers will await
with interest the results of Dr. Lamp's investigation as to whether
the comets furnish an instance of a mere approach or of a real
physical connection.

Stars having Peculiar Spectra. — Prof. E. C. Picker-
ing slates in the Aitronomisc/ie Nachrichttn, No. 3269, that an
examination of photographs of stellar spectra, taken at the
Arequipa Station of the Harvard College Observatory, has led
lo Ihe discovery of four new variable stars in Centaurus,
Lupus, Pavo, and Microscopium, and ten other objects with
spectroscopic peculiarities. Of these, the spectra of five are
classified as Type IV. ; two appear lo belong lo Type V. ; one
(K.A. l8h. 384m. Decl. - 27 55') is a nebula; one h.as H"
bright ; and the photographic spectrum of the remaining object
contains no blue light. To shuw how ililficult it is lo draw
any sharp distinction between nebulx and bright line stars, we
quote the concluding paragraph of Prof. Pickering's communi-
cation. "The photographic spectra of laint gaseous nebula:
and stars of the fillh Ijpe closely roemblc each other, and can
only be Hislinguishcd by Ihe wavelength of Ihe principal
blight line. In ga'cous ncbulic this line (5007) is of greater
wave-length than Wa, while in sl.irs of llic hlih type, the line
4688 is of dhorler wavelength. A superposition of a chart
and spectrum plate of the star whose apprommalc position (or
1900 it R.A. = lsh. torn. Decl. -45' 17', which has b;en
announced ai a star of the fifth type (Astronoinische Nach-
ridilcn, vol. 135, p. 195), shows ihat this object is in reality a
gaieoiLi nebula."

NO. 13 I 7, VOL. 51]

NITROGEN FIXATION IN ALGyE.

I TN Nature of March 29, 1S94, Prof. Marshall Ward gave
a clear and excellent n'siimi.' of cerLtin aspects of the ques-
tion of nitrogen fixation in plants. Since the publication of
that article, fresh and most important additions have been
made 10 the subject.

Last May, P. Kossowilsch published an account of bis experi-
ments on .^Klgie in respect lo their nitrogen-fixing powers {Bot.
Zcilutis, May 16, 1S94), and a short account of this contri-
bution should form an appropriate supplement to Prof. Ward's
paper.

Ill 18SS, Prof. Frank, of Berlin, had stated his opinion that
Alga: possessed the power of free nitrogen fixation.

In 1892, Messrs. Schloesing and Laurent published an account
of their classical researches dealing with many plants, among
which Algae also found a place. Their experiments with these
forms range in two series. In the first they found that if they
kept soil, covered with .Vlgce and containing bacteria of certain
kiuds, under observation for some time, an inciease in nitrogen
was perceptible. .On the other hand, if they prevented the for-
mation of .'Vlga;, although the same bacteria remained, there
was no noticeable addition to the nitrogen of the system. In
the second set of experiments, in which different Algx were
employed, no nitrogen fixation could be perceived. It was
evident from this that either particular kinds of Alga; only have
"fixing " powers, or that suitable bacteria were not simul-
taneously present in the second case, and that .\lgcc can only
fix with the additional aid of these micro-organisms.

In Ihe following year, Koch and Kossowitsch devoted
their attention to the subject, and went over much the same
ground as Laurent and Schloesing, confirming iheir results,
and adding ne«' facts, the value of which, h iwever, was some-
what enhanced by the algal cultures never consisting of any
single species alone, but of several intermingled. Accordingly
when, in 1894, Kossowitsch set himself the task of determining
whether Alg;x; in themselves possess the power of assimil.iting
free atmospheric nitrogen or not, the first obsl.icle he had to
overcome was the difficulty of finding a method by which he
could obtain a single algal species in absolute puiity. This
was ultimately effected by growing the Algx on gelatinous
silicic acid permeated with a nutritive solution, and subse-
quently on sterilised sand also containing food solution. The
steps by which the isolation was effected were slow and beset
with difficulties, which sprang up in the most unexpected
manner, and the pages of Kossowitsch's memoir which deal
with this subject possess a separate and great interest of Iheir
own ; space, however, will not permit that the matter be
detailed here. Having obtained the Alg.x in a state of purity,
the next step was to transfer them to the apparatus in which
their nitrogen-fixing powers were to be lesteil.

'Ihis consisted of a central air-tight vesstl connected with a
series of U-tubes, which were blown into bulbs at certain inter-
vals. These bulbs contained strong sulphuric acid. The whole
apparatus was sterilised, and the Algx under consideration
sown upon a sterilised nutritive substratum in the central vessel.
Air freed from all traces of nitrogen compounds was blown into
the vessel through the U-lul)es, the sulphuric acid in which
killed any organisms which might be contained in this air.

The Alga which was first experimented on was Cyslococcus
(or an extremely similar form). Every precaution was taken in
introducing this into the apparatus.

Using a nutritive solution perfectly free from all nitrates, it
was seen that the Alga: refused lo show any signs of growth ;
it was clear, therefoie, that at le.ast to start development a trace
of nitrate must be added 10 the saml. The .addition of other
nitrogen compounds was found to be useless, and accordingly a
small and accurately measured quantity of a nitrate was mixed
with Ihe food solution in the central vessel. The whole ap-
paratus Ihus fixeil up was placed in the light, and left for some
weeks. At first rapid increase in ihe Algie was noticeable,
but after ihe lapse of about three weeks things evidently came
to a standstill.

The oddiiion of more nitralcfree nutritive solution gave
no result ; but if only the merest trace of a nitrate were
added, iheic was an immediale resumption of activity.

These facts in themselves are very good proof of the inability
of Cyslococcus to fix atmospheric nitrogen ; but to make mailers
doubly sure, a careful chemical analysis was made. This showed

January 24, i«95)

NA TURE

303

that there was no increase in nitrogen during all the weeks
the Algae had been flourishing, and that accordingly no iota of
the stream of free nitrogen which had been consianlly passing
through the apparatus had lieen "fixed." So far, then, the
first Alga which had been put to the test of experiment showed
itself incapable of utilising atmospheric nitrogen.

Kossowitch now turned to fresh expeiiments, choosing ^Igal
cultures of sometimes one, sometimes several species taken
together ; to all ol these he added simultaneously soil-barteria
of mixed sorts. The apparatus employed was very nearly the
same as that above descritjed. In these experiments he desired
to test the supposition of Berthelot and Winogradsky, who
considered the presence of certain organic substances to be
favourable to the fixation of nitrogen ; he accordingly arranged
his experiments in five pairs, both members of each couple
having identical conditions, except that in the one a small
quantity of sugar (dextrose) was added to the nutritive solution,
whilst in the other no organic compound was present. One set
was arranged with Cystococcus and soil-bacteria, and the results
obtained showed that in the absence of organic materials a
small but yet noticeable increase in the nitrogen of the system
had taken place (from 2'6 mg. to 3'i mg.) Where sugar had
been previously added, however, there were three times as much
nitrogen after the experiment as before. In a second pair of
cultures the Alga .Stichococcus and certain bacteria were used,
but here in no case, either with or without sugar, was there any
increase in nitrogen This shows that Stichococcus has in itself
no power of nitrogen fixation.

Another couple contained a mixture of several Algae, Nostoc,
Cylindrospermuni, &c., and certain soil-bacteria. In this in-
stance a very large fixation of nitrogen took place, both where
sugar was present and where not ; in fact, in the former case
the nitrogen was increased more than nine-fold.

All these observations shed much light upon the question of
the relations existing between .A-lgJe, micro-organisms, and
atmospheric nitrogen. They show: —

(1) That at least two Algx — Cystococcus and Stichococcus —
possess no " fixing " powers in themselves.

(2) That many .'\lgce, taken together with certain micro-
organisms of the soil, do possess the power of assimilating
atmospheric nitrogen.

(3) That this power is much increased by the addition of such
organic suhstancesas sugar.

It should be noticed that among the ten cultures used in the
second set of experiments, only two contained definitely isolated
algal species, viz. the cases of the two cultures of Cystococcus
and soil-bacteria.

It was just in this instance, moreover, that it had been shown
that the Alga itself had no capacity for fixing atmospheric
nitrogen. Accordingly, there could be little doubt that it was
through the agency of the micro-organisms that the " fixation "
had taken place in these latter cultures.

The experiments of Laurent and Schloesing had shown that
if in a culture of Alga; and bacteria endowed with "fixing"
powers, the AlgK were destroyed, the bacteria lost partly, if not
entirely, this capacity, which the mixture had possessed. This
pointed clearly to the fact that there was some close relationship
existing between the Alga; and micro-organisms.

There are many facts which seem to indicate the nature of
this relationship.

lierthelot found that the nitrification of the soil only look
place as long as organic compounds were present ; if these were
exhausted, the nitrifying process ceased. Gauiier an<l Drouin
also showed the importance which organic compounds have
with respect to nitrification. Kossowitsch's own experiments,
in which the advantage of adding sugar to the culture was
shown, also point in the same direction.

From such observations as these, Kossowitsch concludes that
the relationship which the -Algx bear to the micro-organisms is
one connected with the organic foc<d supidy of these latter ; he
tliinks that the .'\lg:v, furnished with nitrogen by the bacteria,
i-similate carbohydrate material, part of which goes to their
own maintenance, but part also to that of the micro-organisms.
U is. therefore, in his belief, an instance of symbiosis in which
each supplies the wants of the other. There are many frets,
partly the result of his own o'lscrva^ions, partly the result of
those of others, which uphold this view. If the mixed culture
be placed in the light, there is a far more noticeable nitrogen
increase than when in darkness, .\gain, if a rich supply of
carbon dioxide gas be provided, this is marked by a decided rise

NO 13 I 7, VOL. 51]

in nitrogen-fixing powers. Both these conditions are such as
are known to influence carbohydrate assimilation in chloro-
phyll-containing organisms ; but all experience is antagonistic
to the view that light should be beneficial tothe vital activity of
the bacteria, and there are only one or two exceptional instances
(Nitromonas, &c.) in which carbon dioxide can be directly
assimilated by these micro-organisms.

Moreover, in the cases where the bacteria are brought Into
immediate contact with the Alga, as in those species of .Algae
which are enveloped in a gelatinous covering wherein the micro-
organisms become embedded, nitrogen fixation appears to be
greatly aided, and the addition of sugar to the culture has no
such marked effect as in the instances where non-gelatinous
Algje are employed. The explanation of this seems to be that
the bacteria emijedded in the gelatinous sheath are amply pro-
vided with carbohydrate food without the addition of sugar,
which, therefore, comes more or less as a superfluity.

All this seems to justify Kossowitsch's view of the part played
by the .K\^x in the fixation of nitrogen ; it appears to show that
they have an indirect, but none the less important, influence
upon the process.

This is roughly the extent of Kossowitsch's article ; it has
been impossible to give here its details, the bare outlines of his
researches could alone be mentioned, but it is hoped that
sufficient has been said to show the importance of his work,
perhaps even to indicate the interest which every page of his
memoir possesses, dealing as it does with one of the most
fascinating branches of vegetable physiology.

Rudolf Beer.

THE COMMERCrAL SYNTHESIS OF
ILLUMINA TING H YD ROC A RBONS>

'T'HE direct combination of carbon and hydrogen in the
■'■ electric arc is a true case of synthesis, and if we could
form acetylene in this way in sufficiently large quantities, it
would be perfectly easy to build up from the acetylene the
whole of the other hydrocarbons which can be used for illu-
minating purposes. For instance, if acetylene be passed
through a tube heated to just visible redness, it is rapidly and
readily converted into benzol ; at a higher temperature naph-
thalene is produced, whilst by the action of nascent hydrogen
on acetylene, ethylene and ethane can be built up. From the
benzol we readily derive aniline, and the whole of that mag-
nificent series of colouring matters which have gladdened the
heart of the fair portion of the coaimunity during the past five-
and-twenty years, whilst the ethylene produced from acetylene
can be readily converted into ethyl alcohol, by consecutively
treating it with sulphuric acid and water, and from the alcohol,
again, an enormous number of other organic substances can be
produced, so that acetylene can, without exaggeration, he looked
upon as one of the great keystones of the organic edifice, and,
"iven a cheap and easy method of preparing it, it is hardly
possible to foresee the results which will be ultimately pro-
duced.

In 1836, it was found that when making potassium, by dis-
tillation from potassic carbonate and carbon, small quantities of
a bye-product, consisting of a compound of potassium and
carbon, was produced, and that this was decomposed by water
with liberation of acetylene ; whilst Wiihler, by fusing an
alloy of zinc and calcium with carbon, made calcic carbide, and
used it as a source from which to obtain acetylene by the action
of water.

Nothing more was done until 1892, when Macquenne pre-
pared barium carbide by heating at a high tempera'ure a mix-
ture of barium carbonate, powdered magnesium, and charcoal,
the resulting mass evolving acetylene, when treated with water ;
whilst, still later, Travers made calcic carbide by heating to-
gether calcic chloride, carbon, and sodium. None of these
processes, however, gave any commercial promise, as the
costly nature of the potassium, sodium, magnesium, or calcium-
zinc alloy which had to be used, made the acetylene produced
from the carbide too expensive.

Whilst working with an electric furnace, and endeavouring
by its aid to form an alloy of calcium from some of its com-
pounds, Mr. T. L. Willson noticed that a mixture containing
lime and powdered anthracite, under the influence of the tem-

1 Abstract of a paper by Prof. Vivian E. Lewes, read before ihe Society
of .^rts, Wednesday, Janii.iry 16.

304

NATURE

[January 24, 1895

peratnre of the arc, fased down to a heavy semi-metallic mass,
which having been examined, and found not to be the substance
sought, was thrown into a bucket containing water, with the
result that violent effervescence of the water marked the rapid
evolution of a gas, the overwhelming odour of which enforced
attention to its presence, and which, on the application of a
light, burnt with a smoky, but luminous flame.

Investigation into the cause of this pheno nenon soon showed
that in a propeily constructed electric furnace, finely ground up
chalk or lime, mixed with powdered carbon in any form,
whether it were charcoal, anthracite, coke, coal, or graphite,
can be fused with the formation of a compound known as calcic
carbide, containing 40 parts by weight of the element calcium,
the basis of lime, and 24 parts by weight of carbon, and that,
on the addition to this of water, a double decompositiori takes
place, the oxygen of the water combining with the calcium of
the calcic carbide to form calcic oxide or lime, whilst the
hydrogen unites with the carbon of the calcic carbide to form
acetylene, the cost of the gas so produced bringing it not only
within the range of commercial possil>ijties for \ix per se, but
also the building up from it of a host of oiher compounds, whilst
the production of the calcic carbide from chalk and from any
form of carbon, renders us practically independent of coal and
oil, and places in our hands the prime factor by which nature
in all probability produces those great underground storehouses
of liquid fuel upon which the world is so largely drawing
to-day.

Calcic carbide is a dark grey substance, having a specific
gravity of 2262, and, when pure, a pound of it will yield on de-
composition 53 cubic feet of acetylene. Unless, however, it is
quite fresh, or means have been taken to carefully protect it
from air, the outer surface gets slightly acted upon by atmo-
spheric moisture, so that in practice the yield would not exceed
five cubic feet. The density and hardness of the mass, how-
ever, protects it to a great extent from atmospheric action, so
that in lumps it does not deteriorate as fast as would be ex-
pected, but in the powdered condition it is rapidly aciedupoii.

The acetylene made from it, when analysed by absorption with
bromine, the analysis being also checked by determining the
amount present by precipitation of silver acetylide, gives 98 per
cent, of acetylene and 2 per cent, of air, and traces of sul-
phuretted hydrogen, the presence of this impurity being due to
traces of sulphate of lime— gypsum — in the chalk used for
making it, and to pyrites in the coal employed.

Aceiylene is a clear, colourless gas with an intensely pene-
trating odour which somewhat re-embles garlic, its strong smell
being a very great safeguard in its use, as the smallest leakage
would be at once detected ; indeed, so pungent is this odour,
that it would be practically impossible to go into a room which
contained any dangerous quantity of the gas.

Thi> is an important point 10 remember, as the researches of
Bistrow and Liebreich show that the gas is poisonous,
combining with the bxmoglobin of the blood to form
a compound similar to that produced by carbon monoxide :
whilst the great danger of ihe latter gas is that having no
smell, in presence is not delected until symptoms of poisoning
begin to show themselves, so that no fear need be apprehended
of danger from this source with acetylene.

Acetylene is soluble in water and most other liquids, and at
ordinary temperature and pre-sure— 60 F. and 30 inches
of mercury — 10 volumes of water will absorb 1 1 volumes of the
gu ; but as soon as the gas is dissolved, the water being
saturated i.ike« up no more. Water already saturated with
cr,r . acetylene quite so rea lily, whilst Ihe

gn ■■ in s.iuiratcd brine — loc volumes of a

saiuiu.c. ... nly dissolving 5 volumes of the gas.

The gas is far more soluble in alcohol, which at normal
tempt r.iture and prcsuic takes up six times its own volume of
Ihe acetylene, whilst 10 volumes of paraffin under the same
conditions will ab«orb 26 volumes of the gas. It is a heavy
ga«, having n specific gravity of 0-91.

When a light is applied to ac'l>lcne, it burns with a luminous
and intensely sm >ky llame, and when a mixture of one volume
ol acetylene with one volume of air is ignited in a cylinder,
a dull red (lame run* down the cylinder, leaving be-
hind a mass of tool, and throwing out a dense black
imoke. When aceiylene is mixed with 1-25 times its own
volume of air, the mixture Iwgins to be slightly explosive, the
explosive violence increasing until it reaches a maximum with

NO. 1317. VOL. 51]

about twelve times its volume of air, and gradually decreases in
violence until, with a mixture of one volume of acetylene to
twenty of air, it ceases to be explosive.

The gas can be condensed to a liquid by pressure, Andsell
finding that it liquefied at a pressure of 21 5 atmospheres, at a
temperature of o* C, whilst Cailletet found that at l' C. it re-
quired 0 pressure of 48 atmospheres, the first-named pressure
being probably about the correct one. The liquid so produced
is mobile, and highly refractive, and when sprayed into air, the
conversion of Ihe liquid into the gaseous condition absorbs so
much heat that some of the escaping liquid is converted into a
snow like solid, which cntches fire on applying a light to it,
and burns until the solid is all converted into g.is and is
consumed.

In my researches upon the luminosity of flame, I have shown
that all the hydrocarbons present in coal-g.is and other luminous
flames are converted by the baking action t.iking place in
the inner non-luminous zone of the flame into acetylene before
any luminosity is produced, and that it is the acetylene which
by its rapid decomposition at 1200' C. provides the luminous
flame with these carbon particles, which, being heated to
incandescence by various causes, endow the flame with the
power of emitting light The acetylene, being in this way
proved to be the cause of luminosity, one would expect that in
this gas we have the most powerful of the g.iseous hydrocarbon
illuminants ; and experiment at once shows that this is the
case.

Owing to its intense richness, it can only be consumed in
small flat flame burners, but under these conditions emits a light
greater than that given by any other known gas, its illuminating
value calculated to a consumption of 5 cubic feet an hour being
no less than 240 candles.

flluminalin^ Power of Hydrocarbons for a Consumption of
5 cubic feet of Gas.

Candles.

Methane S'2

Ethane 357

Propane 5^7

Ethylene 7oo

Butylene 123'°

.\cetylene 240-0

It is stated that the carbide can be made at about £^ a ton ;
and if this be so, it should have a great future, as a ton will
yield 11, coo cubic feet of the gas. The lime left as a bye-
product would be worth los. a ton, and the gas would cost at
this rate bs. ^\ii. per 1000 cubic feet, and in illumintiting
value would be equal to London coal gas at dJ. a thousand.
Its easy production would make it available for illuminating
purposes in country houses, whilst its high illuminating v.ilue
should make it useful for enriching poor c0.1l gas.

CHEMICAL CHANGES BETWEEN SEA-
WATER AND OCEANIC DEPOSITS.'
THEnumerous.analysesofsea water by Forchhammer previous
to 18(15, and the later analyses by Dilimar, from samples
collected during the Challenger Expedition, show that while
the salinity— i.e. the amount ol dissolved salts contained in 100
parts of sea-water— varies greatly in difl'erent regions of the
ocean, still the composition of these dissolved sails— /.c. Ihe
ratio of the constituents of sea-salts— remains practically Ihe
same in all the superficial waters of the ocean. Consequently,
it is only necessary to dclermine the chlorine in a dclinite
weight ol water to ascertain at once the respective quantities of
the other salts present in the sample. Ditlmar's examination
of the Challenger waters has, however, shown that lime is
slightly, alihough distinctly, more abundant in samples of sea-
water collected in greater depths than in those samples collected
nearer the surface of the ocean, and Diit mar's tables showing the
difference between the chlorine calculated from the specific
gravity and the chlorine found by analysis - point to difl'erences
in Ihe composition of the sea-salts ; but Ihe observations are

1 Abstract of a I'aptr rf.-.d hcforr. ll.r Roy.ll Society of Edinburjth on
Marctl 7. 1693. by Dr. John Murray and Robcrl Irvrne, and published
in Trail's., vol. xxxvii. pan a, No. 33. _ „

" Dittmar, "Clintlengtr Keporl on ihe Composilion of Ocean W.iter,
" Phys.Chem Clinit Exp , "pan 1. p. 41-

January 24, 1895]

NATURE

305

relatively so few, these differences so slight, so mixed up with
observational errors, and so irregular in their geographical and
bathymetrical distribution, that they cannot be said to indicate
any general law other than a greater quantity of lime in deep
water.

But there is abundant evidence that great changes in chemical
composition take place in the substances deposited on the floor
of the ocean, and, with the view of throwing some light on the
manner in which these changes are brought about, it occurred
to us to examine the compo-i'ion of the sea-water associated or
mixed up with marine deposits on the floor of the ocean, and
especially with that variety of marine deposits known as Blue
Mud.

The depth at which a fine blue mud may form in the sea,
depends entirely on the dejjlh of water and the extent of the
basin ; or, in ether words, on the height and length of the
waves.' In harbours it may be deposited not deeper than i
or 2 fathoms, while along the western coasts of Scotland and
Ireland, which are exposed to the waves of the wide and deep
Atlantic, the true mud-line may be situated at a depth of about
150 or 200 fathoms.

In thi-i paper we state the results of our investigation into the
composition of the sea salts in samples of water enclosed in the
blue muds -from Granton Harbour and Quarry, near Edinburgh,
at Queensferry, N.B., and other places. The water was
obtained by filling a canvas bag with the mud and collecting the
water which filt»?red through, the first portions being rejected.

The Spscific Gravity of the filtrate was about normal for in-
shore waer. ranging from 1024 to 1026.

Chemical C.'mposilion of the Sea-water Salts in Mud-water. —
On comparison with normil sea-water salts, the sulphates were
greatly reduced, while the alkalinity (combined carbonic acid)
was correspondingly increased, sometimes rising to ten times
above the normal.

When a portion of the clear water filtered from the harbour
muds was boiled, a precipitate was thrown down in a crystal-
line form, consisting of carbonates of lime and magnesia in
the following proportions : —

CaCOj
MgCO,

73 '3°
26-70

Before boiling, the water had an alkalinity of o-776ogrms.
per litre, while after boiling it showed an alkalinity of only
0-2200 grms., thus proving that the alkalinity was mainly due
to the formation and presence of these carbonates rendered
soluble by free carbonic acid.

Saline and alliumenoid ammonia ranged from 4 to &o parts,
and I to 5 parts per million, respectively. Lime was much
less, and magiresia slightly less than the normal. The chlorine
and the total baes were higher than normal water of equal
density. Bicarbonate of manganese was present in the water
up to I part in 16,000. Normal sea-water contains no
manganese.

The following table give^ a comparison of the composition
of normal and mud-waters: —

Sodium chloride, XaCI
Magnesium ,, MgCU ..
M.ignesium bromide, MgBr;,
Magne-ium sulphate, MiSO)
Potassium ,, K.^S04

.Vmmonium ,, (NHj)„S04
Magnesium carbonate, MjCO, ..
Calcium ,, CaCO, ..

Calcium sulphate, CaSOj
Manganous carbonate, iMnCO, .,

Average

I :^<•;l-waler.'-'

Mud-w.-iter.

7775S
10-878

79-019
U-222

0-217

0-220

4737
2-465

3-232
2-506
0-206

o'34S
3-600

0729
2686

o-i8o

100-000

1 00 000

' See Miirrav and Renard, " Challtngcr Report on Deep-Sea Deposits,'
p. 1S5. (t. .nion, 1891.)
- Sec Dittmar, op. cit. pp. 137-138 and 203.

NO. 131 7, VOL. 51]

It will be seen that the total salts of the mudwater are low
in proportion to the chlorine, consequently the D value — that
is, th?.;density minus looo divided by the chlorine — will be lower
than normal water. In normal water the D value is 1-457, in
mud water i -430.

The reactions that take flacc in Blue Muds seem to be the
following, and may be distinctly proved from the analyses of
mud-water, as well as from a consideration of the whole sub-
jec During the process of decomposition it appears that the
greater part of the oxygen for the oxidation of the carbon and
hydrogen of the organic substances in the blue muds is derived
from the sulphur salts of the alkaline and earthy alkaline metals
in sea-water, which, in the first instance, are reduced to the form
of sulphides. These sulphides, owing to their instability,
especially in the presence of free or loosely-combined carbonic
acid, are decomposed as formed. The sulphur thus reduced
from the sulphates may in part, on passing as hydrosulphuric
acid into the water immediately above the mud, become oxi-
dised back again into sulphuric acid, which in turn, decom-
posing the carbonate of lime always present in the water (or in
the deposit), would re-form sulphates.

This oxidation is effected but slowly, as the following labora-
tory experiments show : —

Exp. I. — .\ solution of hydrosulphuric acid'(H„S) in pure
water, which at first gave no precipitate with barium chloride,
alter standing a month, gave a distinct precipitate of barium
sulphate, showing that the hydrosulphuric acid had been oxidised
into sulphuric acid (SO3).

Exp. II. — A solution of hydrosulphuric acid in sea-water was
exposed to the air till complete oxidation had taken place. On
titration the sea-water had lost its alkalinity, the sulphuric acid
being proportionately increased.

Exp. III. — Hydrosulphuric acid was passed into water hold-
ing carbonates of calcium and magnesium in suspension, and
resulted in a yel'owish solution of the sulphides of calcium and
magnesium, carbonic acid being expelled. The sulphides so
formed were in turn decomposed by excess of carbonic acid,
with evolution of hydrosulphuric acid, bicarbonates being
formed, the reaction apparently depending on which acid is in
excess.'

A certain part of the sulphides, or it may be of hydrosulphuric
acid, derived from the soluble sulphides by the action of the
free carbonic acid present in the mud, reduces the ferric oxides
of the deposit, forming sulphide of iron, which so long as it is
not exposed to the action of oxygen, remains stable, being in
this respect unlike sulphide of manganese.-' The sulphide of
iron gives the characteristic blue-black colour to the great
majority of the blue muds, especially where there is abundance
of organic matter. It is by this process that sulphur is continu-
ally being abstracted from sea-water and locked up in marine
deposits, which may finally be converted into blue-coloured
shales, schists, and marls.' In these rocks the crystalline
pyrites (FeS.-) has evidently its origin in the processes of death
and decay going on at the time of their deposition at the sea-
bottom, the sulphur of the sulphide of iron being derived from
the sulphates of the sea-water, and not from the sulphur of the
organisms, as generally supposed. This decomposition seems
to be due to the action of bacteria in causing putrefactive
changes in dead organic mailer. We have found that if sea-
water containing putrescitile organic matter be sterilised by
boiling, and thereafter care be taken to prevent the ingress of
bacteiia to this cooled liquid, the changes above indicated do
not take place. .Vpparently the organic matter must be broken
down by bacteria into its component elements, which in the
nascent condition are capable of reducing the sulphates to a
lower form of combination. The bisulphide of iron in the coal
measures has without doubt a similar origin.

I See also C,'w//« rrndus, torn. Ix.v.xiii. pp. 58 and 345 (1S76). Note by
Nau.iin and IMoniholon ; also .Sainic Cl.->ire Deville, Lefons snr la Disao-
ciatioUt i86.|.

■-' lr\ine and Gibson, rroc. Roy. Soc. F.din. p. 37, 1S91.

=* Ttie black or dark blue colour of many shales and schists is due princi-
pally to ihe presence of iron, eiltier combuied with silica as silicate, 01 more
rarely in the condition of carbonate or oxide. 'I tic^e shales, schists. &c..
contain org.imc matter in a state of decomposition. In llie older rocks its
conditioii nearly approaches that of graphitic carbon ; in a d.ark schist from
Argyllshire only o'ot jwr cent, of i;raplntic organic m.-ittcr was found. In
the more recent foruiations the organic matter, "if in siiflficicnt quantity*, may
Rive rise to the formation of petroleum. See paper by Ur. J.J. lahn, /d/o--
tiuchdcr K.K. Geotog. Keichsanstatl, iSjj, lid. 42, Heft j.

30n

NA TURE

[January 2^, 1895

The principal reactions which occur in mud-waters may be
explained by the following formulae : —

(I) RSO, + 2C = 2CO5 + RS,

where K is an earthy alkaline metal.

(*"; RS + 2CO, + H5O = H,S + RCOjCO..
(3) RS + KCO3CO; + H-O = 2KCO3 + H,S.

On the hydrosulphuric acid meeting with ferric oxide (FeoOj)
present in ihs surface layer of these blue muds the following
reaction occurs : —

(4) Fe.Oj + 3H.S =2FeS + S + 3H.O.

Part of the sulphur is thus fixed in the mud, and part, if there
be not sufficient iron in the mud, may escape into the water
above, where, meeting oxygen, it will be converted into sul-
phuric acid (H.SO4), and return into RSO^. The products
RCOjCO; in (2), and RCO3 in (3), or the bicarbonate and
carbonate of the metal are found in the water strained from the
mud.

The increase of alkaline ammoniacal salts points, however,
to a further reaction, by which carbonate of lime is increased
in a slight degree, for as ammonium carbonate [(NH4)X0;j] is
formed by the decomposition of the albuminoids present, the
^ulphatts in the sea-waler by this means are decomposed, sul-
phate of ammonia [(NH^j^SOJ and eaithy carbonates being the
result.

In the red muds and clays, either from the abundance of
oxygen in the superincumbent waters, from the ochrcous mailer
present in the mud or clay, or from the organic matter being
small in quantity, the sulphide o( iron is either not formed, or is
after formation soon oxidised into ferric hydrate, which then
gives its characlerislic red colour to these deposiis.

It may be accepted as the rule that muds containing a large
amount of organic matter relatively to the iron present invari-
ably partake o( the characteristic blue-black colour, whilst if
organic mailer be low in amount, or altogether absent, the
black sulphide is either not formed at all, or is oxidised into
peroxide of iron.

Our altcnti.>n has been recently drawn to a most interesting
paper, read before the British Association, Edinburgh (1892)
meeting, by N. Andrussow, on the " Russian Exploration of
the Black Sea." '

The condition of the water in the Black Sea below the 100-
fathom line, in which hydrosulphuric acid and sulphides exist
in great abundance, i? due to the same action as that now being
carried on so widely in the formation of the blue muds on the
ocean floor, viz. the deoxidalion of the sulphates in the water
by organic matter, and not, as stated in Andrussow's paper, as
simply the decomposition-products alter death of a great number
of organisms. But a compound or double reaction appears in
this instance to be taking place, viz. —

Urstly, on those portions of the bottom within a moderate
distance from the shore, ordinary blue mud containing sulphide
of iron (in large aamunl) is being deposited.

StconJIy, in the rierp water, especially far from the shore,

below a depth of 100 fa-.homs where the oxygen has been used

up, the hydrosulphuric acid, not having enough iron present in

the floating mud to combine with, or to fix it as sulphide of

iron (FeS , is (ound in the free condition. At the same time

there must be a large quantity of free or loosclycomliincd

r^,\. .T..- -.,..\ ,n the water, the result of the deoxidalion of the

anic matter, which naturally would ilicompnse

ihcir inception (or as these are formed). That

this i> pr<ji>aiily the case appears from the fact thai in the

greater Hrpih« of the Black Sea, far fr.m land, there exists a

ing prmcipally ol carbonate of lime,

, which hold in soluti'n lime and

ilphuric and carbonic acids. In the

■il above we have the rationale of

■ ' ■ |> wiler in Ihe Black Sea may be
thru in a state of continual change, Ihe alkalinity in this case

iillt of an
I sent out
- iilrca.ty
-an C',e >•
I.K I'rof.
w'fc paper
ti '* ' " -*■:(''- > jH----»f 1.' ii- »l b ^ici> ..y./i/vj-i.', Januiry

■ &9]. . I .ir c|iit<jme of the v;irioii« pjintft de4lt with.

NO. 1317, VOL. 51]

being due either to sulphides or carbonates in so far as carbonic
acid or hydrosulphuric acid predominates, and not wholly
to carbonic acid as in the open ocean, where sulphides
cannot remain permanent owing to the constant excess
of ox)gen present ; but it is evident that, since the
light grey mud consists principally of carbonate of lime, the
carbonic acid must, it may be on account of the prosure or
temperature, have had the advantage over the hydrosulphuric
acid.

METEOROLOGICAL WORK IX AUSTRALIA."^

T^HE object of the present paper is to place before the Associa-
•*■ lion a brief and succinct account of meteorological work
in Australia. Mr. Russell has already told us, in his interest-
ing paper on astrnomicil and meteorological workers, lead
before the Association at its first meeting in Sydney in 1SS8,
what had been done in the early days of the mother colony,
and brings the history up to the year 1S60, or immediately fol-
lowing the commencement of the active work of the new ob
servaiory completed in 1858, an establi hment with which he
has been associated during the past thirty-four years, and over
which he has presided since his appointment as astronomer in
1870, on the death of Mr. Smalley in July of that year.

It is unnecessary that I should travel over the same ground.
My intention is to carry on the his'ory of which Mr. Rus-ell
has already given us the opening chapter. Indeed, as regards
meteorology but little had been dine before the advent of Mr.
Scott, the fir.^t Director of the Sydney Observatory, in 1S58,
who, Mr. Ru'sell tells me, established twelve meteorological
stations, two of which, Brisbane and R'ckhampton, were in
Queensland, then forming part of New South Wales. Each
station was equipped with a standard barometer, dry and wet
bulb theimometers, maximum and minimum thermometers, and
a rain g^uge.

Meteorological stations had previously — in 1840 — been estab-
lished at South Mead, Port Macqoaiie, and Port Phillip, Vic-
toria beirg then umier the Government of New South Wales.
The observations at South Head were kept up, but, I fear, not
in a very satisfactory or systematic manner, for filtf en years, or
until 1S55. At Port Phillip and Port Macqu,irie they are said
to have been discontinued alter six years. During Mr. Smallcy's
tenure of office several stations started by his predecessor, for
some reason oroiher, probably owing to his bad health, were
closed or allowed to lall into di-use. These were, however,
speedily le-established by Mr. Russell : and I may here men-
tion, as showing the active manner in which that gentleman
has prosecuted the work commenced by Mr. .Scott, that he has
now, in addition to the Sydney Observatory, thirty-five meteoro-
logical stations, having barometers, dry and wet bulb thermo-
meters, maximum and minimum thermometers, and raiit
gauges ; 139 stations furnished with thermometers and rain
gauges ; and 1063 stations having rain gauges.

Tlie Sydney Observatory is equipped with continuous self-
recording barograph and thermograph, pluviometer andanemo
graph, made alter Mr. Russell's own designs, besides under-
ground thermometers at depths of 10 feet, 5 feet, 2 feet 6 inches,
and I inch ; an evapor.ition tank, or atmoineter, 6i:c. ; a record,
combined with the valuatile astronomical work being tione,
worthy of the oldest colony of the gnup, which lud alre.idy
gained distinction in its promotion of science by the D.nves
Point Observatory, erected in 17SS, and the celcbiated Para-
matta Oliservalory, established in 1S21 by Sir Thomas Brisbane.

In Mr. Tcbliutt, Mr. Russell has found a must valu.-ible
coarijutor. That gentleman has not only carried out an ex-
tensive series of astronomical observations entirely at his own
cost, but also furnished his observatory with a complete meteor-
ological outfit.

In Victoria there were only broken records of rainfall,
temperature, and weather, made chiefly by New South Wales
officials in Melbourne, from 1840 to about 1849, and of rainfall
up to 1851. In 1854 observations of barometer and tempera-
ture for astronomical purpo-es only, and of rainfall, were made
at the Williamstown Observatory, then in dmge of Mr. K. L.
J. Ellery. Meteorological observations were also made at
Melbourne by Mr. Brough Smyth, of the Crown Lands De-

1 AbflrftCI of a Paper read before the Auitralanian Association for the
Adv.nncemcnt of Science, by Sir C. Todd, K.C.M.G-, F.K.S. j

January 24, 1895]

NA rURE

307

partment, from 1856 to ihe end of February 185S, when Prof.
Neumayer, now Director of the Nautical Oliseivatory at Ham-
burg, commenced systematic observations at the new Magnetic
and Meteorological Oliservatory, at Flagstaff Hill, Melbourne.
Dr. Neumayer also established several observing stations at the
lighthouses on the coast, and at a few places inland.

On the retirement of Dr. Neumayer in 1S63, the Magnetic
and Metenroh.gical Department was transferred to the present
Astronomical Observatory, then just erected, and placed under
the direction of the astronomer, Mr. Ellery, in whose hands
the institution soon became what it is to-day— not only a credit
to the colony which founded it, but second to none in the
southern hemisphere. He threw all his energy and skill as a
physicist into his work, and early introduced photographic and
other systems, by which we obtain continuous records of all
variations of terrestrial magnetism, barometric pressure, and
changesof temperature, elecirical slates of the atmisphere, and
the direction and force or velocity of the wind, besides thermo-
meters sunk at various depihs (3 feet, 6 feet, and 8 feet) to de-
termine the temperature of the ground ; while, as regards astro-
nomy, we have only to visit the observatory to see that it pos-
sesses some of the finest instiuments in the world.

Besides the Melbourne Observatory, he has established
meteorological stati ns of the second order at Portland, Cape
Otway, Wilson's Promontory, Gabo Island, Ball.irat (Mount
Pleasani), Hendigo, ICchuca, Sale (at the School of .Mines),
and twenty-three stations of the third order, besides 5 15 rainfall
stations judiciously distributed throughout the color./.

In South Australia, thanks to the late Sir George Kingston,
father of the present Premier, we have a continuous record of
the rainfall in Ailelaide from 1839, which that gentleman
maintained until 1878.

Meteorological o'lservations, more or less complete, were
made at the Survey OlTice for a number of years, or until I
took up the work in November 1856, when the observatory
records commenced under my direction as Government
Astronomer.

Since May i860, all the observations have been made at the
West Teriace observatory. For several years I had no assistant,
and having a growing telegraph department to look after and
control, the area of my work was necessarily restricted, and I
laboured under many disadvantages ; but I early established
meteorological stations at Clare, Kapunda, .Slrathalbyn,
Goolwa, Robe, and Mount Gambler, and placed rain gauges at
the different telegraph offices. I also introduced the system of
publishing daily repoits of the weather and rainfall from all
stations at the head telegraph office in .Adelaide.

We have now meteorological stations, having standard or
Hoard of Trade barometers, dry and wet bulb thermometers,
maximum and minimum thermometers, and rain gauges, at Port
Darwin, D.ily Waters, .\lice Springs, Charlotte Waters. .Strang-
ways Springs, Farina, Pott .-Xugusta, Vongala, Clare, Kapunda,
the Agriculiiiral College at Koseworthy, Mount B.irker,
Strathalbyn, Eucla, Fowler's Bay, Streaky Bay, Port Lincoln,
Cape Boida, Robe, Mount Gambler, and Cape Northumber-
land, and 370 rain gauges ; at the lighthouses at Cape Horda
and Cape Northumberland, and at the telegraph offices at Port
Darwin and .\lice S|irings, the observations are taken every
three hours, night and day; at other stations at gh. a.m., 3h.
p.m., gh. p.m.; whilst at Alice Springs there is a large evapora-
tion tank similar to the one at the observatory, which it may
be convenient here to describe.

It consists, first, of a brick tank, lined with cement ; internal
measurement, 4ft. 6in. square and 3ft. 2in. deep. Inside this
tank is another, made of slate, 3ft. scpiare and 3ft. deep, leav-
ing an intervening space between it and the larger tank of yin
Both tanks are filled to the same level, or to within 3in. or 4in.
of the top, fresh water being added as required. The evapora-
tion is measured by a graduated vertical diI, which is carried
by a float placed in a vertical cylinder of copper 4in in diameter
(perfor.ated at the bottom) standing in the inner tank. The rod
is graduated to ,',7 of an inch, and is read off by means of a
fixed vernier to ,,',-, of an inch. A rain guage is placed by the
side of the tank, and both the evaporation and the rainfall are
rea<l at 9a.m. and 9 p.m.

In Tasmania, the Imperial Government established a mag-
netic and meteorological observatory .at Hobart, as part of an
international scheme, in charge of Captain ICay, and systematic
meteorological observations were conducted from 1S41 to 1S54,
hourly readings being taken until the end of 184S. The results
were published, together with the nugnetic observations, in

NO. 13 I 7, VOL. 51]

four large quarto volumes with a short but interesting and in-
structive article by the late Prof. Dove, then director of the
meteorological stations in Prussia. Similar observatories were
established at Greenwich, St. Helena, Cape of Good Hope,
and Toronto, besides places in Europe, and by Russia in A-ia.

From the beginning of 1855, the Imperial Observatory being
closed, meteorological observations at II )bart were carried on
by the late Mr. Francis Abbott until about the year 18S0,
when the Government took up the work, which was entrusted
to the late Captain Shortt, R.N., who died in 1893. Captain
Shortt proved a valuable coadjutor, and established eight other
observing stations, besides a number of rain gauges in various
parts of the island, of which there are now about fifty-nine.

In Western Australia, a meterological observatory was estab-
lished by the Government in connection with the Surveyor-
(ieneral's office, the work being entrusted to .Mr. M. A. C.
Fraser, in 1876, since which continuous records have been
published. Prior to the date mentioned we have r.Vin and
temperature records at Perth from i860 to 1869, taken by Mr.
H. Knight. At present Mr. Fraser has fii'teen meteorological
stations, exclusive of Perth, and ninety-one rain gauges. .\t
Penh there is a self-recording barometer, selected by me when
in England in 18S6. The observations in this colony are very
valuable, extending, as they do, from the south coast well into
the tropics at Wyndham, Ca nbridge Gulf.

In Queensland, as has already been stated, meteorological
stations were started at Brisbane and Rockhampton by .VI r.
Scott, the first Government Astronomer of New South Wales.
I do not know the exact date, but Mr. Scott arrived in the
colony in 1858, and retired in 1862. The instruments were
transferred to Queensland on its separation from the parent
colony, and for some years the duties of meteorologist devolved
on Mr. Edmund MacDonnell, who established several observing
stations and a numf>er of rain gauges.

fn 18S7, Mr. Wragge was appointed, who — with the great
ability and energy which characterise him, and which had
brought him so much renown in starting, I believe at his own
expense, the high level observatory at Ben Nevis, where he
conducted the work under difficulties which would have deterred
most men — soon elTected a complete revolution. Beginning
his work on January i, 1887, he speedily equipped stations of
the several orders all over the colony, along the coast round to
the Gulf of Carpentaria, and inlanil to the very western
boundary of the colony. He classified his stations under five
orders, according to the completeness of their equipment.

Following the example of Mr. Ellery, Mr. Russell, and
myself, Mr. Wragge commenced the system of publishing duly
reports of weather and rainfall, and a synoptic map similar to
the map we had for some time been issuing in Adelaide. He
also co-operated with us in publishing forecasts of the probable
weather during each ensuing twenty-four hours, with this
addition, that he issued forecasts not only for Queensland, but
also for the other .\ustrali.an colonies ; and, as these latter were
made without regard to those published at an earlier hour by the
several local authorities, it has occasionally happened that the
two forecasts for the same colony differed from each other. I
will not venture an opinion as to the desirableness of this inde-
pendent action, beyond remarking that supposing the judgment
and qualifications of the other meteorologists to be equally
good, their local experience, and the possession of more det.ailed
information in regard especially to prognostics, clouds, &c.,
gives them an advantage, and their forecasts should be of equal
value, and be more frequently justified. I regret that -Mr.
Wiagge's collected observations have not yet been published —
from causes, it may be presumed, beyond his control — in such
detail as he himself would wish, and which, in the interests of
science, we all desire. This is to be regretted, as his stations
are so distributed as to represent the climate of all parts of that
large colony.

Besides the stations in Queensland, Mr. Wragge tells me he
has supplied instruments for two sl.itions of the first order in
New Guinea, for one in New Caledonia, one in Fiji, and one in
Norfolk Island, and two others of the second order in New
Guinea.

In New Zealand, I learn from Sir fames Htctor, that from
1S53 meteorological reports were included in the yearly volume
of statistics issued by the Registrar-General, but the obser-
vations were of irregular character, and possessed little value
until 1859, when the woik was taken up in a more
systematic manner. Observers were appointed at Wan-
ganui, .\uckland, Napier, New Plymouth, Wellington,

3oS

NA TURE

[January 24, 1895

Nelson, Christchurch, and Danedic, each being supplied
with a set of slandard instrumenis. The service appears
to have been placed, in the fir»t instance, under the
supervision of Dr. Knight, the Aulitor-Geieral, bat in 1867 it
was tranifcrreJ to Dr. (now Sir James) Hector, unier whose
skilful minageoaent great improvemenis were intro iuced. The
principal stations are supplied with mercurial Fortin barometers,
dry and wet bulb and self-registering maximum and minimum
thermometers, solar and terrestrial radiation thermometers,
Robinson's anemometers, and rain gauges. The height of
every barometer abjve sea-level has been ascertained, and
every reading, as in the other colonies, is reduced to sea-level
and 32° F.

At present there are eight stations, viz. Te Aroha, Taranaki,
Russell, The Bluff, Wellington, Lincoln, Hokitiki and Dunedin,
equipped as above, except Te Aroha, which has an aneroid ;
and seventy-nine rain stations.

To facilitate the transmission of daily weather reports. Sir
James Hector has prepared a series of isobaric maps, which
fairly represents all the different types of weather. These
maps are numbered in consecutive order, and stereotyped
copies are supplied to each station, so that all that is necessary
is for the head office to telegraph to each office the number of
the map to be posted up for the information of the public. In
the same manner typical maps of the pressure in Australia have
been prepared, with the assistance of Mr. Russell, of Sydney.
The reports from a few selected stations, a brief description of
the weather, and the number of the map, are daily exchanged
between Wellington and Sydney (representing Australia) ; the
New Zealand reports being transmitted by telegraph to the
head office in each of the other colonies.

Spread throughout the colonies we have 357 meteorological
stations, more or less completely equipped, and 2575 rain
gauges.

It will be seen that, excepting the magnetic and meteoro-
logical observatory at Hobart, established in 1841, which was
an Imperial institution, systematic observations under the
auspices of the Colonial Governments date, speaking approxi-
mately, from about 1858, a date which cbsely c lincides with
that given by Prof. \Valdo(l86o) as marking a definite epoch in
the development of the modern science of meteorology. The
investigation of the law of storms by Uuys Ballot, Dove, and
others, and the researches of Ferrel, then just commenced, on
the theory of atmospheric motions, cleared the way to further
advances ; and, later on, the utilisation of the electric tele-
graph, which is to the meteorologist what the telescope is to
the astrommer, in extending his field of view over large areas
of the earth's surface, enabled the observer to mark and svatch
the birthplace of storm<, track their course and rate of trans-
lation. The same means informed him of the general distrihu-
tion of pressure, and, knowing the laws governing the circu-
lation of air currents round regions of high and low baro-
meters, he soon felt himself justified in issuing warnings of
coming gales and the probable stale of the weather some hours
in advance. He w,is no longer confined to his own particular
locality, laboriously compiling stati^tics and studying local
prognostic. : he could look far around him, see storms a thou-
sand or more iniici distant, and tell people with a considerable
amount of confidence when they might be expected and what
would be their force. This is the great function of modern
meteorology. Hut, like everything else, it look time. It
required money from the Slate, which was not always readily
forthcoming ; it required, moreover, a complete and extensive
organivaiion rif ' '■ ■ ■ .;;, all working on the same lines
and with the view. It had also lo win the

confidence of .1 . , — , _, which still placed confidence

in quack weather prophets, who could tell them what the
weather would be all the year through, according lo the phases
of the moon. Cunfidrnce, we arc told, is a plant of slow
growth. So it i<, and so it should be if progress is to be made
on a loaiicl, solid, lasting basis.

I

UNIVERSITY AND EDUCATIONAL
JNTELLIGENCE.

I —The Univcr«ity Lecturer in Geography (Mr.

V'ui>; will during the present term give a course of

lectures un the History of Geographical Discovery, in ihc
Lecture-theatre of the Chemical Laboratory on Thursdays at
noon, beginnin-.; on Thursday, January 24.

NO. 13 17, VOL. 51]

The Council of the Royal Geographical Society offer in the
present academical year a Sludenlship of ;^ioo, to be used in
the geographical invesiigaiion (physical or historical) of some
district approved by the Council. Candidates must be mem-
bers of the Universiiy of not more than eight years' standing
from matriculation, who have attended ihe courses of lectures
given in Cambridge by the University Lecturer in Cieoj;raphy.
Applications should be addressed to the Vice-Chancellor not
later than the last day of the full Lent term, March 15, 1895.

Prof. Ewing, F.R.S., has been appoinied Chairman of the
Examiners for the Mechanical Sciences Tripos.

The Gamble Prize for 1S94 has been awarded to Miss Isabel
Maddison, for her essay on " Singular sjlutions of differential
equations of the first order."

The first annual meeting of the .Association of Technical
Institutions was held on Friday last. In the course of an
address, Mr. W. .Mather, M.P., the President for the ensuing
year, remarked that, so far as the pecuniary facili>ies conferred
by the Technical Instruction Acts were concerned, local
authoriiies had the means of annually bestowing on technical
education in England and Wales (i) from grants under the
Local Taxation .\cl, about ;f 780,000 ; (2) from a penny rale
levied on the total rateable value of the whole country,
;^6fi4,5oo ; (3) grants from the Department of Science and
Art, about /'355, 000. The total amount available is this, in
lound nuinuers, /^l, 800,000 per annum. To this must be
added the voluntary aid given 10 technical schools and
institutions. -Vmong the resolutions adopted by the meeting
was one for the appointment of a sub-c immittee to consider
the best methods by which reform could be effecied in the
present system of examination in prac ical chemi-iry adopted
by the Dcpar ment of Science and .\rt, and to confer with other
commiUees appointed with a similar object ; and another to the
effect that the result of examinations should not form the sole
basis for the calculation of the gram in aid of science classes,
but that there should also be a variable grant dependent on the
report of the inspector on the equipmeut .and arrangement for
efficient insiiuctioo.

SOCIETIES AND ACADEMIES.

LO.NDON.
Mathematical Society, January 10. —Major Macmahon,
R.A., F.R.S., President, in the chair. The Chairman gave a
short obituary sketch of Mr. .\. Cowper Ranyard, in the
course of which he |>oiniedout that that gentleman had only been
a pro tan. secretary with the late Mr. G. C. De Morgan. —
The secretaries elected at the first meeting of the .Society,
January 16, 1865, were Messrs. U. Cozens Hardy and H. M.
Bompas. Mr. Hardy resigned at the second meeting (February
20), and Mr. \V. Jardine was elected in his room. — Ihe follow-
ing communications were made : — Note on the expansion of
functions, by Mr. Edward T. Dixon. The author had long
thought that so fundamental a theorem as the expansion of a
lunciion in Taylor's series ought to be demonstrable from firsi
principles in a simple maner which should be apidicable to
complex as well as to real q laniilies. The main feature in the
proof he proposed was that ihe series was regarded not as the
expansion in terms of powers of the inclement of ihe variable,
but raiher as the expansion in terms of the values of the suc-
cessive differential coefficients of the function for the given
initial value of ihe variable. If two functions were equal for a
given value of the variable, they would remain equal while Ihe
variable varied in any specified manner, so long as their rates
of change remained equal and finite. The two sides of the
equation known as Taylor's thcoiem v/ere such functions ; and
Ihe author explained hokv the limita'ions to the application of
Taylor's theorem followed directly from his way of regarding
the expansion. He also showed how the same line of argu-
ment applied to the ca.se of complex variables, and how
in thai case also the limitations could easily be deduced. —
Elecltical dislribulion on Iwo inlersccling spheres, by Mr.
H. M. Macdonald. In Maxwell's " Llectriciiy and Mag-
netism, " vol. i. §J 165, 166, the problem of the distribution of
clettricily induced by an clectiifinl point placed between them
on two planes culling at an angle which is a submuliiple of
iwo right arglcs, and the inveise problem of Ihe comluclor
lotnictl by two spherical surlaces culling at such an angle (the
angle rcfciiing to Ihe dielectric) is solved by the method of

January 24, 1895J

NA TURB

309

point images. This method is inapplicable when the (dielectric)
angle is not a su*imuliiple of two ritjht angles, as has been
shown by W. D. Niven, L.M S. vol. xii. p. 27. The only
other case which has been hitherto solved is, the author thinks,
that of the spherical bowl (Lord Kelvin, " Papers on Electro-
statics and Mignetism." p. 17S). In 'he piper by W. U. Niven,
mentioned above, an attempt is made to deduce the capacity of
such a conductor from the solution of a functional equation f >r a
particular value of one of the variables, but the result obtained
does not seem in the case of the spherical bowl to agree with
Lord Kelvin's. The results obtained ny the author also differ from
those given by Niven. The objfct of the paperis to obtain the
solution in the general case. To effect this, the functional
image of a point placed between two planes intersecting at any
angle is obtained in the form of a definite integral. In the
next few paragraphs the refiuction of thts integral to known
forms is effected in certain cases, and it is shoivn that the inte-
gration can be performed when the angle of intersection is any
submultiple of four right angles; the case in which it is re-
ducible to elli|)tic functions is also discussed. In § 5, the func-
tional image of a line of uniform density parallel to the inter-
section of the planes is deduced. In § 7, the potential due to a
freely-charged conductor bounded l)y two spherical surfaces
cutting at any angle is obtained an I some particular cases dis-
cussed. The capacity of such a conductor is obtained in §8, in
finite terms, and some particular cases are discussed in §9 ; one
of the most interesting of these is the capacity of a hemi-
sphere, which is found to be nearly one ant' a quarter
times that of the complete sphere, showing that the sharp
edge acts somewhat like a c 'n ienser. Some ca-cs are
mentioned in the last piragraph which could be deduced from
the resul's of the preceding ones.^The Dynamics of a Top,
by Prof. A. G. Greenhill, F. R. S. To construct a molelof the
articulated deformable hyperb iloid described by .M. Darboux
in Note xix. to Despeyrous' " Coars de Mecanique," t. ii.,
which shall realise the motion of the axis of a Top, the
ratio of the axes of the focal ellipse mu~t be taken equal to the
modulus k of the associated elliptic funcrir)ns. The parameters
a and /' of the 'wo elliptic integrals of the third kind corre-
sponding respectively to the lowest and highest vertical positions
of the Top, which give the azimuth ^, will be of the form

a = pVJi and i = y K'j + K,

where p and q are real proper fractions. Then two points P and
Q must betaken on the focil ellipse wh >se excentric angles,
measured from the minor axis, a^e given by

am{(l - p -k- ?)IC, k'\ and am!(l - / - ?)K', k'\ ;

and ifthe tangents in and tif are drawn at Q and P, inter-
secting in H, these tangents mike angles

am|(/ -1- i/)K.', k'\ and am!(/> — ?)K', k'\

with the minor axis. The parallel tangents OC and OG being
drawn, intersecting in O, the design of the m )del is completed,
in llenrici's m inner, by drawing any other two piirs of tangents
to the focal ellipse ; the tangents OG an 1 OC being replaced by
a pair of rods representing the generators through O, III and
HJ representing the parallel generators through II, the oiher
pairs of tangents representing the connect in g generators, all freely
jointed at the points of crossing. If OG is held fixed in a
vertical position, the point II opposite to O is constrained to
move in a fixe I horizontal plane ; and now if H is moved along
a herp ilh >de of parameter a + b, the generator OC will imitate
the m >' ion of 1 he axis of a Top. S ' art ing with the hyperboloiil
flattene I in ihe o'a le of its focil ellipse, and \\ at a maximum
distance from OG, the axis OC is in its lowest position ; and as
H moves along the herp^ilhode to its minimum distance from
OG, the axis rises to its highest position, when the hyperboloid
liecomes llitiened in the plane of its focal hyperbola. If the
herpolho le his points of inflexion, the pi'h of a point C in the
axis OC will he looped ; since the m >tion in aznnuth o( OC
vanishes as II pass-s through a point of inflexion. If
/--(/= I, the p )ini Q lies at the end of the minor axis of the
focal ellipse ; the pith of C now has cusps. In the sph -rical
pendulum the points IlanlO lie on the pe lal >f the focal
ellipse wi h respect to the centre ; this gives a geometrical inter-
pretation of the equation

p'a = ±pY;,

discussed in Ilalphen's "Konctions elliptiquc^," i. p. 1 10
The vector Oil represents the resultant angular momentum of

NO. 1317, VOL. 51]

the Top ; and the tangent to the path of H is thus perpendicular
to the vertical plane GOC. When the niomental ellipsoid at
O of ihe Top is a sphere, then OH repre-ents also the resultant
angular velocity. Hut in the general case, when the momental
ellipsoid at O is a spheroid, with axis OC, the resultant angular
velocity is represented by the vector OI to a point I fixed in
the generator HQ ; also H and I describe equal curves with
respect to OC in parallel planes perpendicular to OC, which are
herpolhodes of parameter a - //. Since I can be joined to a
fixed point in the opposite generator OG by a rod of fixed
length, we have Darboux's theorem that the motion of the
Top can be realised by rolling a herpolhode of parameter a-b,
on a fixed sphere. The connection of the motion of a Top with
herpolhodes has also been discussed by Dr. Kouth, Q.f.M.
xxiii. p. 34. As an application, consider Ilalphen's alge-
braical herpolhode

(I- + t"-) (V- + ^)=a*
or

lr^siii=2» .r b-r- + 6* ~ a' = o,

produced by rolling the hyperboloid of two sheets

+ -<■ — . -(--. = I
- a-! - *^ a-

on a fixed pl.ane at a distance b from the centre.

In the associated motion of the Top, p + 1 =
ellipse of the articulated hyperboloid is given by

1 ; I he focal

the coordinates of II and O in its
„ ., b* la- V "

\-

plane are given by

£(';-T{s

The motion of the axis of the Top is given by

ab° / f a* -!- 2*'

'1-

■ -o. . / a*- / f a« -!- 2*» „ )

sin- 9 cos 2ii = 4 x' 2 - — — ;— / \ — — ;— . - cos 9 >

sin'-'fl sin 2J<

^{a* -!- U*)

cos 9

/ ; a^ -I- 4/^1
V '. V(a'-)-8*'

8**)

-t- cos 9

a- + ±i>- , „ "I

—. — - „ - + cos 9 -
v/la* -I- 8/-') I

Thus for instance, if a- = ilr, k = \; the point Q is at an
end of the minor axis of the focal ellipse, and the curve de-
scribed by C has cusps. If a- = 31^-, k — \\ If alphen's herpol-
hode has points of inflexion where >~ = ^^'b'-, and >- varies
between 4/'- and S/'- ; the equation of the focal ellipse is

and the coordinates of H and O are ±J^3(>, ±h^6i. — Some
properties of generalised Brocard circles, by Mr. J. Griffiths.
— On fundamental systems for algebraic functions, by Mr.
H. F. Baker.

Physical Society, January 11. — Extra meeting, in the phy-
sical laboratories of University College (by invitation of Prof.
Carey Foster). — Prof. Kii-ker, President, in the chair. — Prof.
R imsay read a paper, by himself and Miss Dorothy Marshall, on
the measurement of latent heats of vaporisation of various
organic liquids. The liquid to be examined is placed in a small
flask with a narrow neck, and within this is a platinum wire
which has its two ends fused through the bottom, so as to be
capable of conveying an electric current. The flask is com-
pletely enclosed in a jacket, which is filled with the vapour of
liquid of the same kind. Before the current is turned on. the
vapour jacket is ke|it going for some time, so that the liquid in
the fl-isk is raised juvt to its boiling point, but no appreciable
evaporation takes place. As soon as the current is turned on,
boiling commences, and all the heat developed in the wire is
expended in producing evaporation. By weighing the flask
before and after, the mass oI'liquiH vaporised is determined. So
far the authors have only used the method for comparative

,io

NATURE

[January 24, 1895

determinations. Two arrangements of the kind described are
pUced side by side, and the same current is sent through their
two wires, which are joined in seiies and have approximately
equal resistances. The ratio of amounts of heat expended on
the two liquids divided by the ratio of the ma.<ses vaporised, is
equal to the ratio of their latent heats. The delerminalions
made by this method aj^ee well with those of other observers ;
but the authors' object is to obtain values correct wilhin about
per cent, for a large number of liquids, r.iiher than a highly
accurate value for any one substance. In reply to Mr. Griffith-',
the author; s'ated that the platinum wire was found to rise
about 20' above the temperaiuie of the liquid, and Mr. Griffiths
said that his experience had been similar. He did not see
why a very high degree of accuracy should not be obtainable
by the method. Prof. Kiicker expressed his admiration for the
work, and thought it justified by the fact that the results
accorded more nearly with theory than those of other o'servers.
— Mr. Eumorfopoulos read a paper on the determination of
thermal conduciviiy ami emissivity. In the fiist series of
experiments described, two bars of the same material and polish,
and each of uniform circular section, are heated, each at ofe
end, until the di.slribulion of temperature has become steady.
By means of two thermo-joints (one on each rod) a seiies of
isothermal points are then found. According to the ordinary
theory, if the two bars agree in temperature at a given pair of
points, they will also agree in temperature at distances .r, and
.r™ mrasurcd respectively from these pnints, where .Vj and .Vo
aie connected by the relation jr,/.r.j = ^'('■i/rol, r, and r.^ being
the radii of the rods. This relation was not lound to hold
good for the lods examined. In all cases .r,/ajwas further re-
moved from unity than the ordinary theory would lequire. One
conclusion was that the formula usually adopted in such ca'^es
could not be used for the comparison of conductivities, unless
the radii of the rods compared are equal, and their surfaces in I
the same condition. To settle the question, three lirass rods |
were chosen, and their absolute conductivities compared by j
Angstrom's method. The eniissivily was found to vary con- i
siderably with the radius, being greater the thinner the rod ; |
moreover, the value of the emisiivity deduced from the first
sine term of the Fourier's series was in each case found to be
about f2 limes as great as that deduced from the constant term.
— Mr. A. W. P.jrter then read a paper on the influence of the
dimensions of a body on the thermal emission from its surface.
The ordinary assumption is that whe'her a body is in varuo or
surrounded by air, the " emissiviiy " (/.<r. the amount of heat
pas-ing outwards from unit area per second per degree excess
of temperaiiire) is independent of the size of the body. Results
obtained experimentally by Peclet for cylinders and spheres of
difTcreiit sizrs, show that the emissiviiy depend- materially upon
the size of the body. Pcclei's formula; lor cylinders and spheres
surrounded by air show that for each of the c forms the r.ite of
emission per unit surface, excluive of ihe radiation efTeci, may
be represented by a constant plus a term inversely pr porlional
to the radium. The author examines the results of supposing
the lo45 to follow only in part the l.iw of radiation, the remainder
being assumed to follow the law of conduction. He thus
arrives at a formula

a iiog K - log fl)
where e n the emissivity, a the radius of Ihe rod, K Ihe radius
of a hollow cylinder wlich surrounds Ihe bar, and above which
the excesses of lemptralurc arc rrcknncd ; while It and c arc
con>lant<. This f.irmuU has been compared with exiierimental
re«ull» of Ayilon and Kilgour, of M.icl-arlanc, of li utoniley,
and of PcJel, and has also lieen directly checked by experi-
ments on a brass rod when surrounded by wairr-jackets of
diflrrenl radii, as well as on the same bar unjickelrd. The
author finds the agreement lo be much closer than i* the case
on ihe ihrory of cmsiant emis-ivity, or with cmpi<ically de-
duced forirula nf Ayriori and Kilgour, and he concludes i hat
the enclo»ir>g boundary i- a» imp.irt.nni a facor in delermimng
emi"iviiy as the s\ie of the body inrlf. Pmf Carey Foster
ihouk'hi ibal in demonstrating the influence of the enclosure
Mr. Porter had e>lili||-hed an important point. Piof. Ayrton
.igreed a» lo the impoilance of the inflnrncc "f ih> enclosure.
lie urged ihal in »uih e«per>menl< as iho«e of Mr. Porter and
Mr. Kiimoifopiuios, the condMC'i>i'y and emissivity, which
were lumtions of the tcmprraiue, sliould not be asumcd
cooiiani along the bar. Mr. Tioller objected to the use of the

NO. I317. VOL. 51"]

term emissivity as including loss of heat by contact with the
air in addition to the loss by radiation. Mr. Griffiths said
that in some of his experiments, whrre a wire conveying an
electric current was immer-ed in a liquid in order to heat the
latter, the rise of the temperature of the wire above that of the
liquid was found to be ncaily independent of the diameter of
the wire. Mr. Kumorfopoulos said that in each case his com-
parison had been between portions of bars in which ihe range
of temperature was the same. Moreover, the variation of emis-
sivity and conductivity with lemperatuie, as found by other
ob-ervers, would be quite insufficient lo accoun' for his results.
Mr. Porter said that the term emissivity had come to be accepted
as referring to all heat lost at ihe surface of a body, whether by
radiation or by coniuclion and convection. In that sense he
had used the lerm. Prof. Rticker thoughl that emissivity, in
this sense, was not a good term, but to change now would
probably only m.ike greater confusion — Mr. G. U. Vule then
gave a brief outline ol his paper, on the passage of an oscillator
wave-tiain through a plate of conducting dielectric I3y a con-
ducting dielectric the author means a substance whose conduc-
tivity and dielectric capacity are both of importance in the case
under discussion ; and the paper is mainly an invest ii^ai ion of the
following problem : a rrain of plane elcclromngnetic waves falls at
normal incidence on an infiniie parallel sided plate of conduct-
ing dieleciric, whose thickness is finite, and at the first face of
th*- plate, the atnplitude of the vibration vect(»r in the incident
train is zero up lo a certain instant, aid then becomes equal to
an harmonic function of Ihe lime, mul iplied by an exponential
function with negative index: to find what pro| option of the
energy of the whole incident tr.iin is reflected luck, what pro-
portion is transmitted through the plate, and what i>roportion
absorbed. At successive inciHcnctS of reflected and rercflected
wave-trains upon the two bounding fnces of the plate, the am-
plitudes and phasechnngesof reflected and transmi'led portions
have to be taken into account, and the resnl'ing infiniie series
of terms have to be summed. The analysis is very long, but
the results obtained are exact. Curves are given, showing (for
spciial nunieric.il values of the constants of the problem) the
qua..i-periodic variation of the amounts of energy transmitted
and reflfced, as the thickness of the plate is increased from zero
up to a high v.Tlue. Oiher curves a'e given sho\* ing the eflfect
of varying the dii lectiic constant and the conductivity of the plate,
and the diflTcrence between a " damped" and an " undamped"
wave-train in regaid to intensity of refleced and transmitted
portions. The .luihor compares his cilculatcd results with
measurements obtained in the lase of oscillator waves travelling
along a dou'de-wiie cncuit about lOO metres in length; ihe
wires at the middle of the circuit being run ilirough a jar contain-
ing distilled water, alcohol, or a very ililiiie e'ectrolyte. — The
necessary corrections, hovever, are dfficuli and unccilain, and
Ihe author has not found it possible to deal with them in a satis-
factory way. — A letter from Dr. E. II. Harton was read, empha-
sising the necessity for taking into account the damping in the
oscillator-train, and at the same lime pointing out why, in his
opinion, the corrections applietl by Mr. ^^lle were inadetpiate
and failed to yield intelligilile results. Prol. Kiicker congratu-
lateit Mr. \'ule on his work, and on the iin|iortanceof ihe re-ulls
he had obiained. In returning the thanksoi ihe Society lo Prof.
Carey Foster for tlie invitation lo meet in Unveisi y College,
he expressed the pleasure he had fell in observiiig ihe extent
and compl tenes of the lalioraiories. Iliiheno London had
been hehiiid the provinces in this mailer, an I it was gratifying
lo finii that suulenis in London had now such opiior'unilies for
prac-ic.il instruction in physics. The papers wliith had been
reid at that m. eting were a proof that good u-e »as being made
of the lal'O'aioiics for the purposes ol research. The educa-
tional expeiimenis they had seen in the labora'ories were
excellently dtvised, and he hoped that many nf them would
become a part of the regular course of instruction in the
country. Prof. Fiser briefly replied.

Chemical Society, Dec. 20, 1894, — Dr. II. K, Armstrong,
Presiil' n , in ilie chair. — The following papers were rend : — .^n
improved lomi of l-aroin-ter, bt J. N. Collie. The auttior has
devised a port^tble barouieler presenting several new ie;Uuies. —
The coni'iluenls ol I'ifer mjalum, by VV. K. Dunssin and H.
Gainelt, Piprr (n'alum is a VVcsl Indian medicinal plant ;
the au'hors have scpnraicd from it a lomc a kaliiidal subsiancc,
whiili lliey leim pipeiovaiine. C)(jl IjiNO.^, ; it seems likely lo
be of -eivicc in iheiapcuiics — Noie on iht- aciive cmsiituent of
the I'ellitory ol medicine, by VV. K, Dunsian and II, Gar-

January 24, 1895

NA TURE

A I

nett. The Pellitory of medicine (Anacydus pyrethruni) con-
tains an active sulistance, which they name pellitorine ; it closely
resembles pi^jerovatine, and is possilily identical with it. — The
determination of some high temperature freezing-points by
means of platinum-resistance pyrometers, by C. T. Ueycock
and F. il. Neville. The authors give the results of freezing-
point dcterminali ins of a number of metals and salts. — The
preparation of adipic acid and some of its derivatives, by \V.
II. Ince. Contrary to the statements of Arppe and Malaguti,
adipic acid is not producd in the action of nitric acid on sebacic
acid or beef suet. The author has prepared o-monobromadipic
acid in a state of purity, and has obtained o-hydroxyadipic acid.
— The action of hydrogen chloride on the oxides of calcium,
baiium, and magnesium, by V. II. Veley. Dry hydrogen
chloride does not act on quick-lime or magnesia at ordinary
temperatures ; at higher lemperatures action occurs. Baryta
is acted on at all temperatures by the dry gas. — Latent heat of
fusion, by H. Crompton. — .Metallic tartrasenites, by G. G.
Henderson and A. R. Ewing. Arsenious oxide dissolves in hot
solutions of acid tartrates, giving tartrasenites ; the sodium salt,
CjlIjOgAsONa, aiHoO, is stable and crystalline. — Note on
the inleracti.:n ol hyjrogen sulphide and bismuth haloid com-
pounds, by M. M. P. Muir and E. M. Eagles.

Zoological Society, January 15. ^Dr. St. George Mivart,
K.R..S., Vice-Presideiii, in the chair. - Mr. P. Chalmers
Milchell exhibited and gave an account ot a tibia and other
bones of an extinct bird of the genus .-Kpyomis from Ceniral
Madagascar, wtiich hid been lent to him lor exhibition by Mr.
Joseph H. Kenn. Wi.h these bones wasassociated a skull of a
spet.ies ot Jlippopotanius. — Prof. G. B. Howes exhibited and
made remarks on the photograph of an embiyo of Ornilho-
rhynihus. — The Secretary exhii i ed, on bfhalf of Mr. K.
I.ydckkcr, a lif.-sized drawing of /Jiiiriis zinlceti, a neiv and
remaikably small furm of fl)ing S([iiirrel ffi^m West .Vfrica,
recently destriled at Berlin. — Lord Lilf n-d sent, for exhibition,
the skill! fa duck, beii;ved to be a hybrid "etween the Mallard
(Anas l/Dsckas) and tlie 'iesX (Qiieri/ncJitla iricca), that had been
caught 111 a decoy in Nurihampionihire. — Tne Rev. T. R. R.
Stcbbing exhibiieil a specimen of a species of Peripatus from
Antigua. — Mr. Frederick Chapman gave an account of some
ForaminifcM olitamed by the Royal Indian Marine Survey's
s.s. htvcitii^alor from the Arabian S^-a near the Laccadive
Islands. 1 11c auihor described the forms fjund in the samples
sent him. .\, many as 277 species and varieties were
enumerated, some ol which were new to science. .Several of
the species, which were here recorded f )r the first time from
recent soundings, had been previously known from the Pliocene
deposits of Kai N'icobar. One of the forms found in these
recent deposits, viz., Antphistt'^ina yadiata (F. and M.), was
described t)y the autr.or as showing the presence of initr^eptal
canals, a sliucture which had hitherto appeared to bt? restricted
to Nummulres and allied forms. Examples of embryonic
forms of 1 he same .'•pecies were also noted as being present in
the peripheral chariib*rs of the adult shell. — -V communication
was reaii Irom Mi. P. R. Uhler containing an enumeration of
the llemiptcra-llomopiera of the Isl.ind of St. Vincent, West
Indies. This pajier hati been based on specimens submitted to
Mr. Uhler by the joint Committee of the Royal Society and
Biiti,h Association for the exploration of ihe Lesser .Viitilles. — A
communication from Mr. 1'. D. A. Cockerell contained a
descii.'lion of a new species of the family Co.ciil/e belonging to
Lichlciiiia, a genus new to the fauna of the Nearctic region.
'Ihe species was nained /.. lycii. — Mr. Sclater read some notes
on the lecent occurrence ol the IJaibary Sheep in Fgypt. .V
iVick of these sheep had vis ted the eastern bank of ihe Nile
above W.idy Il.vlfa in the summer of 1890. — .\ second paper
by Mr. Sclater contained so-ne notes on the recent breeding of
the Surinam Water Toad {Pipa aiiiciicaiia) in the Society's
reptile-house.

Entomological Society, January 16. — The sixty-second an-
nual meeting ; .\Ir. llenryjohn Elwes, President, in the chair. —
Auabstiaci ol thetreasurcr'saccounts, showing agood b lance in
the Society's lavour, having been reail by Mr. W. F. H. Bland
ford, one of the auditor-, the secretary, Mr. II. Goss, read the
report of the Council. It was then announced that the follow-
ing gentlemen hid been elect dl as officers ami Council lor
1895 : — Picident, Prof. Raphael Meldola, F. R. S. ; treasurer,
Mr. Robert Mcl.achlan, F. R.S. ; secretaries, Mr. Herbert Goss
and the Rev. Canon Fowler; librarian, Mr. George C. Cham-

NU. 13 17, VOL. 51]

pion : and as other members of the Council, -Mr. George T .
BethuneBaker, Mr. Walter F. II. Blandford, Dr Frederick
A. Dixey, .Mr. Henry f. Elwes, Mr. Charles J. (Jahan, Prof.
Edward B. Poulion, F.R.S., Dr. David Sharp, F.R.S., and
the Right Hon. Lord Walsingham, F. R.S. It was also
announced that Prof. Meldola, the new President, would
appoint Lord Walsingham, Mr. Henry J. Elwes, and Prof.
Edward B. Poulton, Vic<"- Presidents for the session 1895-96
The outgoing President then delivered an interesting address
on the geographical distri'mtion of Lepidoptera. He remarked
that though a great deal had been written of late years on the
geographical distribution of plants, mammals, birds, fishes,
and reptiles, comparatively little had yet been done by ento-
mologists to show how far the natural divisions of the earth's
surface which have been established for other classes were
applicable to insects. Perhaps the proportion of known as
compared with unknown inects was still too small, and the
classification of the known species still too uncertain, to allow
anything like the same methods to be applied to insects that
had been used for mammals by Dr. W^allace, F. R.S., for birds
by Dr. Sclater, F. R..S. , and Dr. Bawdier .Sharpe, .Tnd for
plants by Sir J. Hooker, F.R S., Mr. Thiselton Dyer, K.R.S.,
and Mr. W. B. Hemsley. The President enumerated
the genera of the Rhopalocera, and pointed which of them
were characteristic of the various regions and sub-regions into
which the world had been divided by the zoologists and botanists
above mentioned. He also exhibited specimens typical of these
regions and sub-region=. The President then alluded to the
prosperous condition of the Society, and to the increase in its
numbers and income. Reference was also made to various
Fellows of the Society and other entomologists who had died
during the year, special mention being made of Herr H.
T. Christoph, Mr. J. Jenner-Weir, Dr. F. Buchanan White,
M. Lucien F. Leihierry, Pastor Wallengren, Dr. Jacob
Si an berg, Major-General Canlen, Dr. Ilearder, and Mr.
Wcllman. — A vote of thanks to the President and other officers
of the S iciety having been passed, Mr. Elwe=, Mr. McLachlan,
Mr. H. Goss, and Canon Fowler replied, ami the proceedings
terminated.

Royal Meteorological Society, January 16. — Mr. R.
Inwards, President, in the chair. — ^The Council, in their
report, reviewed the work done by the Society during the past
year, and also slated that additional accommodation had been
provided to meet the growing needs of the library. Forty-five
new Fellows had been elected during the year. .Mr. Inwards,
in his presidential address, dealt with the subject of
"weather fallacies," which he Ireited under the head of
saints'-day fallacies, sun and moon fallacies, and tho.se
concerning animals and plants. He also referred to
the almanac makers, weather prophets and impostor?,
who have from time to time furnished the world with fit
materials for its credence or its ridicule. — Mr. C. Harding read
a paper on the gale of December 21-22, 1S94, over the
British Isles. This storm was one of exceptional severity,
es^iecially over the northern portions of England and Ireland
and in the south of .Scotland. It developed energy very
quickly, and travelled with great rapidity. The self-recording
anemometers show that the greatest violence of the wind
occurred at Fleetwood, where the velocity was 107 miles in the
hour between S.30 and 9.30 a.m. on the 22nd ; and for four
consecutive hours the velocity exceeded 100 miles. This is the
greatest force of wind ever recorded in the British Isles, and is
10 miles an hour in excess of the highest win 1 velocity in the
great storm of November 16-20, 1893. K\. Huljhead the wind
in squalls attained the hourly velocity of 150 miles between
10 a. m and no in on the 22nd. The strongest force was
mostly from Ihe north-westward. Much destruction was
wrought both on sea and land, and there was a heavy loss of
life.

Paris.

Academy of Sciences, January 14. — On a method of
verification, a(>plicable to the calculation of s:ties in astrono-
mical problems, by M. Poincarc. — On autumn cultivations for
green manures, by M. P. P. Deherain. The author insists on
the importance of autumn cultivations for subsequent dig-jing in,
lor two main reasons : (1) nitrates are retained by the roots of
growing plants, which would otherwise be lost in the drainage
waters ; (2) if burieil at ihe proper time, the decomposition of
the vegetable matter affords a considerable amount of useful
fertilisation. — Experimental researches on the critical point of

;i2

NA TURE

[January 24, 1895

liquids holding solid subslances in solution, by M. Raoul
Picie:. From the re:>ults obtained, it appears that either solid
uoUics become );a^eoas and mix with other gases at tempera-
iurcs below their points of fusion and under considerable
partial pressures ol their own vapours, or the solid bodies
present are dissol%'ed in droplets momentarily formed in many
pUces in the mass of gas above the critical lemperaiure of the
solvent. In the latter case, a solid depjsit should be formed
on superheating the vapours. This point has to be investi-
gated.— The treatment of vines, infested by phylloxera, with
peat-moss ijipregaaied with a mineral oil, by M. F. de Mcly.
Details are giveu of a process which appears to efiectually
olear olTtne pest without injuring vegetation. — On a method of
drawing a right line by the aid of jointed links, by M. Kaoul
Bricaid. — .\1. J. Janssen called the attention of ttie Academy
to the contenu and scope of the Annuain du Bureau des Lon-
^iiwits. — .\ letter from the Koniglichc Gesel!icha/l der Wissen-
ukajten of Guningen was read inviting the .\cadeiny to send
delegates to Innsbiuck, to lake part in a meeting lor the con-
sideration of the problem of investigating the variation of the
intensity of gravity with the geological character of the crust
of the earth. — On the application to dillcrential equations of
methods analogous to those of Galois, by M. Jules Urach. —
On the determination of the equations of continuous finite
groups, by M. E. Vissiot. — On the law of transmission of
energy between the source and the conductor, in the case of a
)>ermanent current, by M. Vaschy. —On the production ol
cathoue rays, by .M. Joseph de Kowalski. (i) The production
of the so-called cathode rays does not depend on the dischaige
from metallic electrodes across a rarehed gas (2) I'hey are
produced chiefly where the primary illumination attains a con
sideraule intensity ; that is, where the density of the current
lines is very considerable. (3) Tneir direction of propagation
IS that of the current lines at the place wiiere the rays are pro-
duced, from the negative to the positive poles — On the en-
irainemcnt of luminous waves by matter in motion, by M. G.
Foussereau. — On some properties of silver sulphide, by
M. .\. Ditte. The double sulphides, 4AgjS.K„S.2H„0 and
3.\g5S.N»5S.2H;0, are desciibed, and a method lor their pre-
paraiiun given. — On the preparation of amorpDous silicon, by
.M. V'igouroux. Tbe preparation is carried out by heating to auoul
540 a perfectly dry mixture of silica, magnesium, and mag-
De:.ia. The silicon, by the usual tieatment with acids, is
obtained as a pulverulent, maroon-coloured substance. — On the
protomorpbic state : sulphides of zinc and manganese, by M. A.
Villiers. — On some sensitive reactions ol aniiao-benzoic acids,
by M. Oechsner de Coninck. — On a class of nitrdes, by M.
Albert Colson. — On the constitution ol bc\ameih> Icnctctrainine,
by .M.M. K. Cambier and \. tirochei. — On eihylcnic methylal,
by M. Louis lleniy. — New researches on pectasc and on the
pectic lermen'.ation, by M.M. G. liertrand and A. Mailcvre.
Peclase exists in solution in the cellular sap of acid fruits, just
as in carrot roots. There is no insoluble peclaic. In acid
fruits, its action is only appaienl aftei neutralisation. — On the
influence exercised by the nervous system and the internal
pancreatic secretion on histolysis. Facts illustrating the
mechanism ol normal glyca:mia and sugar diabetes. A note by
M. M. Kaulmann. — The I'leistocene of ihe valley ol Cham-
btry, by MM. J. Revil and J. Vivien. — Remains of striped
hyaenas from the qualenary ol Bagncies-de-Uigorre (llauies-
PyiciiCcsj, by M. Kdouard liatle. — On the quaicmry phos-
phorites from the region ol Uzcs, by M. Charles Dipcrel. — An
aDcmomeier wiih multiple-electrical indications and automatic
orientation, by .M. Jules Richard.

ISeklin.
Physiological Society, December 21, 1894. — Prof, du
iJois Rtymond, I'icsiucni, in the chair. — Prol. Waldcycr
gave a Ungihy account of the most recent researches on
the formalive stiuctures of the nervous sy>icm, la)iiig special
stress 00 the following staicnicnls. The entire nervous
s)siem coDsisit of siirgle elements which m^y most con-
veniently be called " neurons," each of which is com-
|'>ostd ol a nerve-cell and its processes. These processes are,
on the one hand, protoplasmic "dendrites" which rapidly
become blanched, and, on the oihcr hand" neurites 'or" axons,"
xhicb give oil collateral branches, soon become nicdullaicd,
and end in fine branching!!, as also do the collaterals. Each
nerve-cill has . nly one *'axun." The dcndnics convey impulses
10 the Cell, the neuriies or axons convey impulses from the cell.
All ncive-hbrcs, both dendrites and ncuritcs, end freely in hnc

NO. I317, VOL. 51]

branchings. Every physiological path of conduction, whether
from the periphery to the central nervous system, or vice vetsd^
consists of two or more neurons, never of one. Conduction
in the neurons is always longitudinal. Impulses are transmitted
from one neuron to the other only by means of the free endings
of the terminal branches. The lecture was illustrated by a
series of schematic diagrams and some preparations.

BOOKS, PAMPHLETS, aad SERIALS RBCBIVBD.

Books. — L'Industrie dcs Araneitia ; W, Wagner (St. Pctcrsbourg). —
Summer Studies of birds and iiooki ; W. \V.irac Fowler (MacmillanX —
Over de Bevruchting der Bloemcn : J M.icLcod (Gent, Vuylstcke).— Lens-
Work for Amateurs H. Orford (Whitiakcr).— Sieel Works Analysis: Prof.
J. O. Arn -Id (Whittakcr).— Handbook for Hcafordshirc, litdfordshire.
and Huntingdonshire (Murray). — Calcareous L.emcnu : G. K. Redgrave
(Griffin). -An Elementary Text-Book of Metallurgy Prol. .-\. H. Sexton
(Grirfin). — Electrical Engineering ; W. SItngo and A. Brooker, new edition
(Longmans). — A Popular Treatise on the Phy>iology of Plants : Dr P.
botauer, transia CO by Prof. Weiss (Longmans). — whence C'-mcs Man,
fruiu '■ Nature" or Iroin *' God "?:A. J. Bell, new edition (Isbister). —
Why does Man Exist ;• : A.J. Bell, new edition (Isbister).— A Collection
of Appliances and Apparatus lor the Prevention of Accidents in Factories,
2nd edition (Oulau) — Elcktrophysiologic . Prof. W. Biedeniiaiin, Erste
Abthg. (Jena, Fl^ch:r). — Aligemeine Physiolonie : V)x. Max Vcrwom
(Jena, Fischer). — Manuals of Etemcniary Science: Zoology. Prof. A.
Newton, new edition (S.P.C.K). — Manuals of Health: Air, Water, and
Disinfectants: Dr. C. M. .\ikman (S.PA..K.).

Pamphlets. — Elementary Practical Chemistry*. J. T. Hewitt and F. G.
Pope (Whutaker). — Latent Heat of Steam and Absolute Zero ; W. Donald-
son (Waterluw).

Sekials.— L'.\uthropologie, tome v. No. 6 (Paris).— Quarterly Review,
January (Murray). — Archives of Surgery, January (\\csi). — Journal of
Anatomy and Physiology, lanuary (Griffiu) — Botani>chc Jahrbucher,
Ncuiizchutcr Band, 4 He t (Leipzi*:). — Koyal Natural History. P.art 15
(WiiriieJ. — RendiconiodeirAccadcmiadellc Scienie Fisiche c Matematische.
sene 2^, Voi. viii, Fasc. 11'^^, c 13" (Napoli) — Bulletins de la SjCici^ D'An-
tnropologic de Paris. Nos. 5-7 (Paris) —Bulletins of the R .sc Polytechnic
Institute. No. i : Physical Units; Prof. T. Gray (Terrc Haute, Ind.).

CONTENTS. PAGE

A Bad Method in Text-Books. Uy Prof. E. Ray

Lankester, F.K.S. . . 2S9

The Siudy of Rocks, liy J. W. J 290

Our Book Shelf:—

Dubois: '• Pnhecanthropus Erectus, eine Menschen-

aelinliche Uebergan^sfoim aus Java." — R. L. . . 2yi
Gregory : " The Hlanei liarih. .\n Asitronomical

Imroduction to Cieoyraphy " 291

Letters to tbe Editor: —

The Hodjjkinb Frizes.— Prof. S. P. Langley ... 292
The Artificial Speclrum Top.— Captain W. de W.
Abney, C.B., F.R.S. ; J. M. Finnegan and B.

Moore 292

The Kinetic Theory of Gases.— Prof. Arthur

Schuster, F.R.S -293

" Acquired Ch.iracters." — J. T. Cunningham ;

John Cleland 293

Chin'->e Iheuiies of the Origin of Amber. — Kuma-

gusu Minakata ... 294

KliyiuHo.tenni^ terrestris in Germany. — H. Simroth 294
The •' Proceedings of the Chemical Society." —

Prof. William Ramsay, F.RiS. . . -294

Philosophy ami Nauiral Science. — David Wetter-

han ; The Reviewer 295

Some Early Teriebtnal Magnetic Discoveries per-
tain'ng to England. (Jlluilraied.) Jiy L. A.

Bauer 295

The Teaching University for London. By Dr. W.

Palmer Wynne 297

Notes 29S

Our Astronomical Column : —

The Pcrseid .Meleois 3°'

Comet 1S94 1 (Uenninj;) and Brorsen's Comet . . . 302

Stars having; I'eculiai Spectra 302

Nitrogen Fixation in Algx. liy Rudolf Beer . . . 302
1 he Commercial Synthesis of Illuminating Hydro-

carbonu. liy Piof. Vivian B Lewes 303

Chemical Ctianges between bea-Water and
Oceanic Deposits. By Dr. John Murray and

Robert livinc . . 304

McleoroluKical Work in Australia. By Sir C. Todd,

K.C.IVI.G,, F.K.S. ... 306

University and Educational Intelligence 30S

Sucieticb Aiwl Acailomies . . 3°^

Books, Pamphlets, and Serials Received 312

NA TURK

31;

CEO-MORPHOLOC Y.

Lithogenesis der Gegenwart. Beobachtungen iiber die
Bilditng der Gesteine an der heutigen Erdoberfldche.
Driller Theil einer Einleituiig in die Geologie als
hislorische Wissenschaft. By Johannes Walther. 8vo.
pp. viii. + 535 lojS- (Jena : G. Fischer, 1894.)

Geotektonische Probleme. By A. Rothpletz. 8vo. pp.
175. 107 figures, and 10 plates of sections. (Stutt-
gart : E. Schweizerbart, 1894.)

Morpiiologic der Erdoberfldche. By Dr. Albert Penck.
Ratzel's " Bibliothek Geographischer Handbiirher."
Svo. 2 vols. Vol. I. pp. .xiv. + 171. 29 figures. Vol. II.
pp. X. + 696. 38 figures. (Stuttgart : J. Engelmann,
1894.)

RECENT discussions in England as to the relations
between geology and geography have only served
to show that these sciences are so intimately associated
that no satisfactory line of demarcation can be drawn
between the two. These three works illustrate the extent
to which this view has been accepted in the schools of
Germany and Austria, and the valuable results to both
sciences that follow from a due recognition of the fact.
The three works agree in this, though they are very
different in their aims and subject-matter. The first is a
manual on rock-formation ; thesecorid, a monograph on
one type of earth-movements ; and the third, a systematic
text-book of structural geography. One is a restatement
of the principles of correlation, another a protest against
speculation, and the other a compilation of the classifi-
cations of, and theories respecting, the dil't'erent geograph-
ical forms. They have, however, so much in common in
their methods, that they may be conveniently noticed
together.

Prof. Walther's work goes even further. It shows not
only the inseparability of geology and geography, but
the need of a knowledge of biology for the correct appli-
cation of the evidence of palxontoloi.'^y to stratigraphy.
Since the days of William Smith, the evidence of fossils
has been regarded as final in both historical and strati-
graphical geology. It is therefore rather startling to find
a geologist stating that the history of the earth could
have been written from the structure of the rocks alone,
without the assistance of the organic remains within
them. It has been the rule, in the determination of tht;
age of any particular bed, to accept only the evidence
of the fossils as valid. So long as the method of corre-
lation .by the proportions of species and genera common
to two horizons, was confined to comparatively simple
areas, it gave fairly trustworthy results. But when ex-
tended beyond Britain and the North European plain, it
was the cause of serious confusion. The classification of
the very variable Cainozoic deposits of the Mediter-
ranean basin were involved by it in chaos ; it caused
beds in Australia to be assigned to the highest instead of
the lowest division of the Cainozoic, and led to lime-
stones in the West Indies, probably formed in part
within the historic period, being referred by high
authorities to the Miocene. Even in such a simple

NO. 1318, VOL. 5r]

sequence as that of England, the method led to errors,
as, e.g.., in the exaggeration of the gaps in the geological
record, such as that between the Chalk and the Lower
London Tertiaries. Occasionally a warning against the
neglect of lithology would be uttered, as by Godwin
Au-ten and Sorby, or an effort made to use it. But the
former were ignored ; and the latter were not at first
judicious, as in the case of the famous generalisation,
that we are still living in the age of the Chalk, a sugges-
tion about as useful as that we are still living in the
Silurian, because sandbanks were formed then and are
forming now.

For the recognition of the necessity for the limitation
of palaeontology, we have in the main to thank biology.
Ta.xonomy— the study of distribution— has shown that
age is only one of many conditions that govern the
character of a fauna ; the depth, the composition of the
sea-floor, the distribution of the ocean currents, the
proximity of different bathymetrical zones, all exercise
an influence. Thus a fauna is often more allied to an
extinct one, than to those which are living simultaneously
in adjoining areas. Taxonomy has exercised its in-
fluence in two ways. In the first place, it has insisted on
the proper recognition of the self evident fact that de-
posits change in space as well as time : that a sandstone,
e.g., may change into a clay laterally as well as vertically.
Thus it is now recognised that the dividing line between
the Gault and the Upper Greensand is a varying litho-
logical one, and that the latter formation in one area was
formed at the same time as Gault was being laid down
in another. In the second place, it has led to the adop-
tion of more detailed, zonal stratigraphy, and the demon-
stration thereby, that adjacent beds of different composi-
tion, and containing different faunas, have often been
deposited simultaneously in stratigraphical continuity.

These views have gradually worked their way into
general recognition by geologists, but Walther's is
probably the first text-book in which they have been
adequately expressed. The inconvenience in map-
making, and still more in map-reading, which they
involve, has led, perhaps, to an unconscious bias against
them. Hence, even when theoretically admitted, their
guidance has not been accepted practically. Walther's
" Geologie als historische Wissenschaft ' is, however,
saturated with the results of biological teaching, the
influence of which we may trace in nearly every page of
the " Lithogenesis." Though well skilled in palaeon-
tology, he does not attach an exaggerated importance to
the evidence of this science, but seems even to tend to
the other extreme : if he does not underrate its value, he
at least protests that it is less indispensable than has
been thought. In his ardour for lithology, he goes so far
as to say (p. 53S) that " if we had an exact phenomen-
ology of rocks, we could, without fossils, from the rocks
alone, read the history of the earth." Walther's work is
an effort toward such a " phenomenology," by an ex-
position of the lines along which it m.iy be attained. He
defines (p. 537) the objects of lithogeny "as the elucida-
tion of the development of the fossil rocks by the
investigation of rock-forming processes now in opera-
tion." He urges that rocks should be studied from the
same point of view as animals and plants. He thinks
that in comparative lithology, ontogeny should hold the

I'

314

NATURE

[January 31, 189-

same place as it does in comparative morphology. This 1
lithology he divides into three sections, equivalent to
those adopted in biology. Thus, he says that the study
of rock structure answers to comparative anatomy, the
development of rocks now in process of formation
to embryology, and petrography and stratigraphy to
paleontology. Throughout the book he introduces
biological terms and phylogenetic trees to emphasise
his views. For example, he classifies rocks as homo-
logous and analogous ; as the former, he includes all
those which are formed in the same " Facies-bezirke,''
and as the latter, those which are formed under
different geographical climates. And climate, in the sense j
of this later-day lithology, is " the sum of all the meteor-
ological and oceanographic conditions, including organic
and inorganic processes,' which affect the formation of a j
rock. The use, however, of these terms often appears of
doubtful value ; thus, when he states that the lavas of an
oceanic island are only homologous with those of a
continent, we doubt whether we are in any way better
for the information.

The work is divided into three parts, entitled,
respectively, " General Lithogeny,' " the existing Facies-
bezirke," and '• the bases of Comparative Litho-
logy." The first of these occupies fourteen chapters :
it begins with an account of the destruction, deposition,
and alteration of rocks. The destructive processes he
divides into four classes : weathering, chemical, physical,
and organic ; ablation, both of ice and rock surfaces ;
transport ; and corrasion. The last he restricts to the
comparatively insignificant polishing action of loose
material carried about by the wind, rivers, ice, or sea.
-According to Walther's scheme, denudation results from
ablation, transport, and corrasion ; he attributes it to
four agencies, viz. the wind acting by " deflation," run-
ning water by " erosion," glacier ice by " exaration," and
the sea by " abrasion." The second part of the book is
the longest ; each chapter is devoted to the description of
a group of deposits, which he says are " homologous," as
they are formed in the same " facies-bezirke" or
geographical zone. Thus, on the continents there is the
zone of the Polar Regions, with moraines, humus, ochre,
&c. ; the temperate zone, with its black earth, loess, &c.;
the desert girdle, with its sand and salt deserts, and
dried-up lake-basins ; and the tropical zone, with its
laterite and cotton soil,&c. Other groups of homologous
rocks are the products of continental volcanoes, shore
deposits apd those of open seas, of oceanic abysses ;
coral reefb, and volcanic islands. Very obvious objections
to this classification could be easily raised, and it cer-
tainly could not be recommended for the purposes of
ordinary teaching ; but as long as it is used only to illus-
trate the association of deposits, formed under any par-
ticular set of geographical conditions, it is extremely
useful. The different subjects treated in the work are,
moreover, brought well up to date. Thus, e.g., in the
account of the supposed iron-secreting organism Gail-
lonella, the latest botanical researches of Molisch are
summarised, and its character left more doubtful than
ever. The chapter on coral-reefs is especially well
done. The sketch of the life of a reef (pp. 915 y-7),
which he calls the "richest of bionomic assemblages,"
IS the best we know. The definition (p. 909) of a coral
NO. I 3 18, VOL. 51]

reef as being essentially formed of branching corals,
with calcareous sediment filling the interspaces, ex-
presses a truth which is often overlooked. Even this is
enlarged on another page, where it is stated that geolog-
ically a reef must be regarded as including not only the
calcareous sediment on the surface, but that which is
formed around it, to the depth of as much as 3000
metres. He illustrates the slopes around coral islands
by the numerical method, due to Dietrich, which brings
out clearly the differences between such atolls as those
of the Bahamas and Keeling Island. The mean
figures which he gives do not, however, teach much.
It is interesting, therefore, considering that the coral
island question is handled with full knowledge of all the
latest information, and that the author's own investiga-
tions took place upon a region to which Darwin's theory
was never intended to apply, to notice that he accepts
that theory as substantially correct. It is surprising,
considering the accuracy of the rest of the chapter, that
a recent photograph of a Pectinia quadraia is again
quoted (p. 899) as a Manicina arcolata.

The third section of the work is that which enunciates
the general conclusions. It contains short chapters on
the correlation of facies, the equivalence of rocks, the
changes in the facies of deposits, and the lithological
significance of organisms. This part of the book is, how-
ever, the least satisfactory ; perhaps because most useful
originality had been expected in it. Variations from the
ordinary method of treatment and overstrained analogies
had been passed in the hope that they would be turned
to some account. This part of the book is, however, so
general in its treatment, that the conclusions are rather
indefinite. Nevertheless, the work is throughout so
novel in treatment, so up to date in its information, that
this cannot seriously impair its value.

Rothpletz's " Geotektonische Probleme " is a very
different work from either of the others. Its title is a
little misleading ; one might expect from it an account
of earth-movements in general, and a discussion of the
theories of earth-structure by which these may be ex-
plained. One is, therefore, a little startled at finding
that it commences with a protest against theories, and a
warning against the danger of ideas creeping into general
acceptance, under cover of a convenient term. Me points
out, for example, that Suess'sterm of " horst " for a moun-
tain mass formed of one block of material, is so useful
in descriptive geology, that it has been widely adopted.
Rothpletz fears, therefore, that Suess's theory of the
origin of " horsts," and its corollary that horizontal beds
are never uplifted, may be unconsciously accepted.
Similarly he foresees that, by the adoption of other con-
venient terms, the whole heresy of " Suessism " may
gradually work its way into a position of influence it
would never attain by its merits. The perils to geological
progress threatened by this insidious " hypothesis building
phantasy," as Rothpletz calls it, he thinks can only be
averted by the critic, whose duty it is to bring all
hypotheses to the test of facts. And the author sets him-
self to pcrlorm this task. His volume is devoted to the
class o( earthniovements known as " overlhrusts''
When cases of the inversion and repetition of strata were
first noticed, they were regarded as due to the folding of
the beds. During recent years, many of these have been

January 31, 1895]

NA TURE

j'o

shoun to be due to tV e thrusting of one set of beds on to
another, either horizo- tally or at a low angle. Rothpletz
shows that the;e overthcusts are even wider in their dis-
tribution than is now ueierally admitted. He describes
tiic most important ca^os, summarises the literature and
\ ariou; theories regarding them, and states the explana-
tion which seems to him to agree best with the facts.
Most ot the examples quoted, the author has personally
examined.

The first case taken is that of the classical Linth in the
Glarus. This, as interpreted by Escher and Heim, has
exercised a great influence on geological thought. The
valley has previously been regarded as due to a great
double fold. Rothpletz, however, maintains that it is a
■' graben " or rift-valley, formed by the subsidence of the
block of material which once filled it up. One difficulty
that hitherto told against this explanation, was the fact
that the marginal faults had never been discovered. Roth-
pletz, however, maintains that they are there ; he de-
scribes them at one point, in a section which, he declares
p. 10), "must silence the most utterly sceptical." The
denial of Heim's famous double fold necessitates a new
interpretation of other features in the geology of the
lountry. Thus the rocks in theSchild — the mountain to
the west of the town of Glarus — have been explained by
Heim as the crushed-out beds of the middle limb of the
fold. Rothpletz, however, maintains — and his evidence
seems conclusive — that they are due to an overthrust.
He adds a further difficulty to Heim's theory, by showing
that if true it is inadequate as it stands. The country is
more complex than a double fold can explain ; a treble
and a quadruple fold at least must be assumed, for the
beds repeat themselves more than thrice. This Roth-
pletz explains by the assumption of three overthrusts,
which he names after Schild, Kapf, and Plattenalp.

The next case considered is that of the mountain mass
of Sentis, to the north of the Glarus area. This was
described by Escher von der Linth in 1857. It was then
said to be remarkable in having a great series of faults
crossing the axes of the folds, but none parallel to them.
This was confirmed by the maps and memoirs of Escher's
pupils, and Suess, therefore, in l8cS5, made the Sentis
thetypeof a class of mountain structure named" Blatter."
Some discrepancies between the descriptions and the
maps led Rothpletz to re-examine the country. The
result is that he finds numerous faults parallel to the
ridges, as well as across them, and also a series of over-
thrusts which occurred later than the folding, and earlier
than the transverse faults.

From the Sentis it is natural to turn to the Juras.
This range has long been famous owing to the ingenious
devices designed to enable the fold theory to account
for the rock sequences that occur there. But the
"vanishing trick" diagrams, by which the absence of
certain beds has been explained, have always been
viewed with suspicion ; they seemed too much like the
schemes by which Ptolemaic astronomy was reconciled
with facts. Miiller in i860 demonstrated their insuffi-
ciency, but they still survive. Rothpletz discusses this
fold theory in its three most plausible modifications, viz.
the faulting of over-folds ; the folding of an area after the
rocks in the centre have been raised by a double fault ;
lateral contraction forcing one side of a valley of erosion
NO. 1318, VOL. 51I

over on to the other. Rothpletz dismisses these, and
accepts the theory of overthrusts along slightly inclined
thrust-planes.

The fifth case is that of the highlands of the north-west
of Scotland. This is so well known, that the author adds
nothing new, except a doubt as to the relation of the
minor and major thrusts. He notes with relish the
abandonment of the view at first announced that the
thrust-planes started as a result of the inversion of over-
folds.

A simple example of overthrusting in a much later geo-
logical period is afforded by the granite of Lausitz in
Saxony, which occursabove the Turonian limestones. This
superposition was explained at first by the chalk having
been deposited under an overhanging cliff, and then by
the granite having been dropped as an erratic. Both
these theories were ridiculously inadequate. The most
popular explanation assigned an eruptive origin to
the granite ; the absence of contact-alterations and of
apophyses from the granite is fatal to this. Overthrust-
ing is the only theory left, and this Rothpletz accepts as
satisfactory. The earth-movements in the coal-fields of
Westphalia, Belgium, and northern France are next
considered : these have long been known to be ex-
tremely complex. The explanation now accepted, is
summarised with great lucidity, and illustrated by over
thirty figures and three plates of sections. It attributes
the present structure of the country to the inthrusts of
slices of complex composition between other deposits.
The last case considered is that of the area of the coast of
Provence and the French Alps. The author has not
personally examined the ground, and so would have pre-
ferred not to discuss it. Haug, however, has suggested
that the assumed " pli-failles" or fold-faults) are often
only inverse faults, and that the latter are capable of
explaining the phenomena without the hypothetical folds.
Rothpletz, therefore, thinks it advisable to discontinue
the use of the word " pli-faille," and suggests the substitu-
tion of " faille de recouvrement," or some other term
which does not beg the question.

In the concluding chapter, Rothpletz summarises the
general characters of overthrusts. He remarks that their
importance is being more widely recognised, and that
they are accepted now in explanation of many phenomena
for which the agency of folding was formerly invoked.
He thinks that they probably always occur in mountain
formation. He discusses their relations to the earth-
movements with which they are associated, as far as our
present knowledge enables these to be generalised. Thus,
the thrust-planes occur approximately parallel to the
folds, but the inclination of the planes is usually in the
opposite direction to that of the mountains : this might
have been expected, as it is in harmony with some of
Daubree's experiments. Divergences between the strike
of folds and overthrusts, however, occur, and are ex-
plicable by the later origin of the latter. The inclination
of thrust-planes is almost always different from that of the
beds or folds ; the former, however, both above and below
the thrust-plane, occur in their normal sequence. Friction
breccias, mylonites, &c., occur along the thrust-plane,
while " schleppung," or terminal curvature of the beds
toward the plane, is generally developed. A single thrust-
plane may occur; but, as a rule, there are many parallel

i6

NATURE

[January 31, 1895

to one another, and this results in the type named by
Suess the " Schuppen-structure." The chapter concludes
by a consideration of the classification of earth-move-
ments, and its difficulties ; that advanced by Suess, he
recognises as the most important, but he does not admit
it as at all satisfactor)-.

This shyness of classifications is in striking contrast to
the attitude of the last work, in which all the types of
" earth-forms" are classified in a detail, and with a term-
inology, which seems at first needlessly elaborate. The
work is a systematic account of the orography or struc-
tural geography of the earth, and is quite unlike any
existing textbook. It has taken more than ten years to
prepare. The delay has been partly due to the enormous
amount of literature that has had to be considered, but
also to the fact that during this period two works have
appeared which have completely changed the whole
aspect of geographical science. These are Richthofen's
" Fiihrer fur Fiirschungsreisende," and Suess' " Antlitz
der Erde." The former introduced a more scientific
classification of " earth-forms" or geographic types,
while the latter has revolutionised our ideas as to how
those eanh-forms have been developed. One of the
great advantages of Prof. I'enck's work is that it is a
re-description of the earth's surface in the terminology
and in accordance with the views of these two leaders of
geographical thought. It is a book which it is impos-
sible to summarise. It is a compilation showing on
every page the most- detailed care and accuracy. No
one acquainted with Prof. Penck's previous writings will
be surprised at his extensive knowledge of the literature
of both geography and physical geology. The numerous
historicalsummaries that occur in it, show how thoroughly
the author has ransacked literature, and how well the
book has been brought up to date. Works published so
late in 1894 as that containing Heim's description of the
Pleistocene earth-movements in the Alps (" Die Enste-
hung der Alpinen Randseen "), and Giinther's memoir on
the influence of atmospheric pressure on isostacy, are
included. It is only natural that English literature is
not so thoroughly done as the German, but important
omissions are surprisingly few. The two most important
are probably the absence of reference to Whymper's
work on aneroids, from the chapter on altitude
determinations, and to C. Reid's explanation of the
formation of the chalk coombes, from the discussion of
the origin of dry valleys.

The work is divided into three parts, dealing respec-
tively with general morphology, the surface of the earth,
and the sea. Its plan is based on the conception of the
earth's surface as composed of a series of " earth-forms "
which range between the extremes of mountains and
valleys. The description and classification of these,
and the study of their origin and development, form
the subject-matter of geographical morphology. This
science, therefore, depends on the literature of geodesy,
geology, and geojjraphy. The book commences with an
outline of general morphology, which depends in the main
on the first of these. The chapters on mathematical
geography, and on morphography and morphometry,
are probably the most valuable of the five devoted to this
part of the subject. In these he states the latest con-
clusions upon various debated problems. He points out
NO. I 3 IS, VOL. 51]

(p. 9) that the amount to which the form of the earth
deviates from an ellipsoid of revolution is between ± 200
and ± 250m. He discusses the relative value of the
various geoids, and expresses a preference for Northern
Europe, for Bessel's instead of Clarke's, which is used
in England. The principles of earth-measurement are
briefly considered ; the standard levels used in ditierent
countries are tabulated, and their relations to each other
shown. The value and method of construction of hyso-
graphic, klinographic, hypsoklinographic, and bathy-
graphic curves are shown. The difficulties in the
determination of altitudes caused by the uncertainties of
refraction are pointed out. The inevitable inaccuracy
of map lines is illustrated by a list of the lengths assigned
to a portion of the Istrian coast in a series of standard
maps ; the figures range from 105 km. to 22381 km. The
calculation of the volumes of continents is considered,
and finally elaborate tables given of geographical
statistics. The ratio of land to water is taken as 2'54
(p- 97) ; the principal previous estimates are given from
the time of Riccioli, who in 1661 estimated that the land
was in excess in the proportion of S to 5. An interest-
ing sketch of the literature on " geographical homo-
logies " shows how early attention was drawn to the
remarkable parallels and contrasts in the distribution of
land and water. This part of the work concludes with the
consideration of the question of the permanence of oceans
and continents. Penck quotes Cayeux as if this author s
investigations proved the terrigenous origin of all the
chalk, and though he notices Blanford's arguments, he
does not seem to appreciate their full significance. His
sketch of the literature of the subject shows that, though
with some striking exceptions, the difference on this
question has been one between geologists on one side,
and geographers on the other. In this connection it is
interesting to note that Penck accepts (p. 167) the view
that the ocean floors have a higher specific gravity than
the continents, and places the difference, according to
Helmert's work, at •001 of the specific gravity.

The second part of the book describes the surface ol
the earth, or the " Landoberflache." The first section of
this deals with the composition ol the earth's crust, and
the forces that act upon it. The figures given to illus-
trate Suess' terms are very clear and instructive ; the
table of geological systems is, however, out of date ; the
C^rdovician is not accepted, and the Tertiary and Quater-
nary are each regarded as etjual to such divisions as the
Trias and Permian. The account of the agents of denuda-
tion is very detailed and thorough. The hydraulics of
river action (pp. 259-385) is treated with especial care,
and the references to the literature of the subject include a
much wider range than is usual. The controversy as to
Baer's law of the influence of the earth's rotation on the
direction of rivers is clearly summarised, and the truth
of the law upheld ; great stress is laid upon the deepen-
ing of the Rhine on its left bank in the regulated por-
tions of its course. The author attributes to glaciers
considerable erosive power ; he maintains that the
characteristic featuie in erosion by ice, is that the ex.
cavations vary in depth with the strength of the rocks, so
that true rock basins are formed (p. 409). He still
accepts the glacial origin of cliques, and even approves
of Ramsey's views of the origin of some of the Alpine

January 31, 189

.]

NATURE

1^1

lakes. The description of the existing " earih-forms," or
geographic types, occupies the first 460 pages of the
second volume. These "earth-forms" are divided into
eight types — plains, heaped-up mounds, such as moraines
and dunes, valleys and the highlands through which they
run, basins, mountains, areas of subsidence, and finally
fissures and caves. The characters, classification,
method of formation and terminology, including both
local and scientific names, are stated in detail. A sketch
of the literature of each type is also given. The chapters
on " Wannen " or basins, and on mountains, are probably
the best. The book closes with an account of the ocean;,
and the deposits on their floors.

The one serious drawback to this book is its complete
neglect of the evidence of zoological distribution. Thus,
for example, the questions of the origin of the Caspi in
Sea and the lakes of Nicaragua, are fully considered, but
no reference is made to their faunas. No theory, how-
ever, could be accepted which failed to account for the
anomalous characters of these. But it would be too much
[" etpect Prof. Penck to show the same mastery of the

'.erature of biology as he does of geography and geology.
In this respect, Walther's book is superior to that of
I'cnck. But it is idle to estimate their respective merits,
lor the three works are so different. One cannot com-
pare Walther's statements of the principles of correlation
with Rothpletz's detailed mapping, and either with
I'enck's digest of literature. I'enck's, however, will pro-

lably prove the most generally useful of the three. An
llnglish translation would be of great service, by calling
attention to a branch of geography that has been un-
accountably neglected in this country. Thus, in the
I ieographical Society's " Hints to Travellers," instea ! of
the details of Richthofen's " Fiihrer," the subject is not
even mentioned. A translation would, moreover, neces-
sitate greater precision in the definition of geographical
terms, and the introduction of many new ones, for which
there are now no equivalents in English, and which are
essential to the scientific treatment of geography.

J. W. Gre(;orv.

ORGAMC CHEMISTRY.

The Rise and Devclopineiil of Ori^anic Cliciuisliy. By
Carl Schorlemmer, LL.D., F.R.S. Revised edition,
edited by Arthur Smithells, B.Sc, Professor of
Chemistry in the Yorkshire College, Leeds. (London :
Macmillan and Co., 1894 )

FOR some time this excellent historical survey of the
development of organic chemistry has been out of
print, and students of chemistry will heartily welcome
the appearance of a second edition, which has been
extended, in order to include a review of the more im-
portant results of the original investigation of the last
ten to fifteen years.

Facing the title-page is an exceedingly good likeness of
Schorlemmer, admirably reproduced from a photograph ;
then follows a short biographical notice, giving a brief
sketch of the author's career, in which his brilliant
researches are described. This is a very welcome
addition to the book, because, as the editor points nut,
Schorlemmer, with characteristic modesty, mentions
NO. 1318, VOL. 51]

these r^earches only on two occasions in the book
(pp. 141 and 197), and then but very briefly.

Chapters i. to v. are very much the same as in the
first edition, only a few slight alterations having been
made. Chapter vi. deals with the perfection of the
I methods of organic analysis by Liebig, and these impor-
tant researches, which affected in such a marked manner
the subsequent development of organic chemistry, are
perhaps scarcely di^cu-sed at sufficient length ; a more
detailed account of the history of organic analysis is to
be found in Roscoe and Schorlemmer's " Treatise of
Chemistry" (vol. iii. p. 40). This chapter vi. also con-
tains a short sketch of the work which led to the dis-
covery by Raoult of his well-known method of deter-
mining the molecular weight knoivn as the cryoscopic
method.

Chapters vii. and viii. have not been much altered, but

chapter i.\-., which deals with the constitution of benzene,

tautomerism, and the asym:netric carbon atom, has, as

was to be expected, been largely added to, and made to

I embrace most of the important results of recent work.

The constitution of benzene is dealt with in a veiv
interesting manner. Baeyer's researches, on succino-
succinic ester, which led to the rejection of Ladenburg's
prism formula, are discussed, as well as those of Bam-
berger, on the reduction of naphthalene derivatives, the
results of which may be said to have completely con-
firmed Baeyer's views.

After a short description of Laar's tautomeric hypo-
thesis, the remainder of the chapter is taken up with
Le Bel and van't Hoffs theory of the asymmetric
carbon atom, and with VVislicenus' development of this
theory. In a future edition, more emphasis might, per-
haps, with advantage be laid on the general applicability
of these theories, so that the student may not receive
the impression that they have only been found valuable
in the explanation of isolated cases, as, for example, the
isomerism of the malic and tartaric acids, and of fumaric
and maleic acids.

The first part of chapter x. is devoted, principally, to
the history of organic synthesis, and contains an account
of Frankland and Duppa's work on aceto-acetic ester,
and of Conrad's researches on malonic ester, showing
the value of these ethereal salts in synthetical work.
The synthesis of malic, tartaric, and citric acid is also
mentioned.

A very valuable historicaf sketch of the chemistry of
the sugars, including a clear exposition of the more
important results of E. Fischers classical researches, fol-
lowed by an account of Ladenburg's synthesis of coniine,
and of the synthesis of uric acid, by Horbaczewski, con-
cludes this excellent chapter.

The remainder of the book does not differ materially
from the first edition, except that a very good index of
authors' names and subjects has been added.

Students of organic chemistry must always be in-
terested in the development of the science, and to them
this work will be cordially welcome. It is a thoroughly
readable book, written throughout in an attractive
manner, and comprisuig in one small volume all the
facts necessary for understanding the growth of organic
chemistry.

Schorlemmer wrote, whenever possible, in German,

3«Ji

NA TURE

[January 31, 1895

and never had any real facility in writing English. The
editor is, therefore, to be congratulated on the very satis-
factory manner in which he has performed the difficult
task of preparing this book for the press. Great care has
evidently been taken in reading the proof-sheets, as we
have only noticed one or two unimportant misprints.

OUR BOOK SHELF.

British Birds: being Coloured Illustrations of all the
Species of P-isserine Birds resident in the British Isles,
■with some Notes in reference to their Plumage. By
Claude W. Wyatt. 410. Pp. iv. 25. London :
William Wesley and Son, 1S94.'

The author is .1 well-known ornithologist, who has made
two expeditions, of which the results have been pub-
lished one to the Peninsula of Sinai, and the other to
the Magdalena Valley in Colombia — and these proved
that he was not only a good collector, but also a
keen field-naturalist. He then travelled extensively, and
visited many parts of the globe, observing the habits of
birds, .tnd making sketches of every kind of scenery.
The latter became a great feature in the plates of the
•' Monograph of the .Swallows (Hirundinida;)," which he
brought out in conjunction with Dr. Bowdler Sharpe,
who contributed the letterpress of the work, while Mr.
Wyatt drew all the plates.

The present volume is the first of two which the author
proposes to publish, the one before us dealing merely
with the resident Passeres of the British Islands, while
the second is to contain figures of all the migratory
Passeres, the Picarian birds, the birds of prey, and the
pigeons ; but the game birds, waders, and swimming birds
will be, presumably, treated of at a future period. Fifty
species are illustrated by Mr. Wyatt in his first volume,
and occupy twenty-five plates. As with his pictures of
the swallows, the author makes a great feature of his
accessories, and some of the landscapes are very pretty,
and are evidently drawn from nature. The attitudes of
the birds are life like, and some of them are exception-
ally good, the crowi alone striking us as failing in
massiveness of bill. The letterpress is of the simplest.
and would have been all the better for more complete
references to standard works, as many of those given are
incorrectly quoted. It is, however, more as an artist
than as a writer that Mr. Wyatt shines, and he is to be
congratulated on having produced a very handsome
volume, with beautifully coloured pictures of some of our
most familiar favourites. As regards quality of paper,
printing, colouring, and binding, there is nothing left to
be desired.

Standard Methods in Physics and Electricity Criticised,
and a Test for hleclric Meters Proposed. By H. A.
Naber. (Published by the Author, 1894)

From the title and table of contents of this woik, one
would expect to find a treatise on experimental physics.
This expectation is, however, rulely dispelled when one
commences to examine the letterpress. After a very
brief description of the form of gas voltameter which
the author has devised (see N.m ukk, July 12, 1S94), more
than a hundred pages are devoted to what presumably
the author considers an exhaustive examination of the
different uses to which this voltameter may be put. The
fact that his voltameter has a considerable resistance,
causes the author considerable trouble, but he consoles
himself with the reflection th.n a Cardew or other volt-
meter generally has a resistance of from 100 to <)00 ohms.
The difficulties encountered in measuring a qu intity of

NO. 13 '8. VOL 51]

electricity by copper or silver deposition are dwelt upon,
and a new objection is raised, namely, that since the
deposits have to be weighed, variations in gravity will
affect the results ! At another part of the book the
ordinary balance is considered devoid of sufficient
accuracy, since the arms have generally different lengths,
and Nicholson's hydrometer is recommended as a sub-
stitute when great accuracy is desired. In a chapter on
sound, the author strongly recommends bicycle-wheels as
a motive power. Apparently the cycle-wheels are to set
themselves in motion, since the idea of driving any piece
of machinery "by hand'' is derided, and the great
waste which takes place when water and other
motors are used, is dwelt upon as a reason for their
abandonment. One has met with the library steps which
can be converted into half a dozen other articles of
furniture ; but these old friends sink into complete
insignificance when compared with this gas voltameter
and the numerous uses claimed for it, such as blowing
soap-bubbles full of oxygen and hydrogen, which on
being exploded can be used as fog-horns : supplying
oxygen to aeronauts, or to explorers in coal-pits after an
explosion ; and preparing chlorine. It can also, we are
told, be used as a barometer, pyknometer, ice calori-
meter, dylatometer, thermostat, hygrometer, anemometer,
level, or for exhausting incandescent damp bulbs. The
above are a few of the uses claimed, and are extracted
from what the author describes as not an " exhaustive
list " ! W. W.

Electrical Engineering, for Electric Light Artisans and
Students. By W. Slingo and A. Brooker. Pp. 740,
New and revised edition. (London : Longmans,
tireen, and Co , 1895.)

An admirable work, covering the whole field of electric
lighting. Though designed to include those branches of
the subject prescribed in the syllabus issued by the City
and Guilds Technical Institute, its scope is such as " to
make it embrace the requirements, not only of those
actually employed in the electric lighting industry, but
also of those who, while having little or no electrical
knowledge, have under their supervision various kinds
of electrical machinery.' The book is not merely a
descriptive catalogue of electrical machinery, like some
thai we know, but a clearly-written, and amply-illustrated,
volume which has proved of great service to engineers
during the past five years, and, in its revised form, is
sure to hold its own in the future.

Lens-Work for Amateurs. By Henry (Jrford. Pp.231.
(London: Whittaker and Co., 1895.)

A LKNS is defined in this volume as " a portion of a
refracting medium . . . bounded by two spherical sur-
faces which have a common axis." In the following
paragraph, lenses with one of their surfaces plane, are
described ; wherefore wc would ask Mr. Orford, why he
did not include these in his definition .' This, however,
is but a detail, .^s a whole, the book is a trustworthy
guide to the manufacture of lenses, suitable alike for the
amateur and the ^ung workman. It is profusely,
though rather coarsely, illustrated by diagrams, and the
instructions are simple and practical.

Manual of Practical Morbid Aualomy. By H. D.

Kolleston, M.A.,M.D., F.R.C.P., and A. A. Kanthack,

M.D., F.R.C.P. Pp. 240. (Cambridge: University

Press, 1894.)

A PRACTICAl. handbook for the post-mortetn room,

showing how to carry out a systematic examination of a

body, and indicating what morbid changes should be

looked for.

January 31, 1895J

NA TURE

319

LETTERS TO THE EDITOR.

( The Editor doc not hold himself responsible for opinions ex-
pressed by his correspondents. Neither can he undertake
to return, or to correspond ivitk the writers of rejected
manuscripts intended for this or any other part of Nature.
No notice is taken of anonymous communications. ]

A New Step in Statistical Science.

Contribution's of an abstract kind to statistical science are so
liltle read \iy the hull; of statistician-, that the scope of the re-
markable memoir by Prof. Karl Pearson may be unappreciated
by them unless attention is pointedly direcled to it.'

Slaiisticians are conversant with the use of curves to epitomise
masses of data. The forms of the majority of these curves are
skewed or humped, and have hilherlo been nondescript, except
as Prof. K. Pearson's previous memoir showed, some of them
may be dissected inlotwoor more normal curves, having different
constants. It is only a few curves that are symmetrical and con-
form closely to the normal law of facility of error. These few
have been much studied, the numerous and valuable properties of
the normal curve beinij extremely helpful in dealing with them.
When the conformiiy between the observations and the normal
law ceases to be close, the latter must be applied warily. When
the discrepancy is serious, it becomes unsafe to trust the theory
at all. Not a few statisticians have chafed under these limita-
tions, and felt that the normal law is too limited in its
};rasp to satisfy their needs. Now at length, it lurns out,
thanks to Prof. K. Pearson, that ihe normal law admits of
being regarded as nothing more thin a very special case of a
highly generalised theor\', by whose aid curves may be drawn
that shall fit every one of the observed curves he has tried as
yet. The shapes of these arc curiously varied. Their list
includes the dimensions of shrimps and prawns, of American
recruits and of school-girN, of IJavarian skulls, of frequency of
enteric fever, and of divorces, of variation in house value, in
butter-cups and in clover, in pauper percentages and in a
mortality curve. Only those who have studied the delicate an t
oddly-shaped drawings of these observed curves on a large
scale, upon which the equally delicate/iV/ty/ curves have been
superimposed, can adequately appreciaie the wonderful close-
ness between the pairs of outlines. There can be no doubt
that the descriptive efficiency of Prof. Karl Pearson's method
is of the highest order.

The question of the utility of the method to ordinary
statisticians has now to be considered. First, as to its
descriptive [inwers. We are already able to describe the whole
of any normal series by means of only two numbers ; say, by
the average of all the members of the series, and by the mean of
the several departures of its individual members from that
average. Henceforth, by the use of more constants, we shall
be able to do the same to any series. A few figures will
always serve as the equivalents of a vast amount of tabular
matter.

The second and higher use is to afford a clue to the cause or
causes of variety. It has long been a dream to me to select a
peculiar and often recurring form of curve, and to study with all
possible care the conditions under which it has been produced, so
that whenever a new curve of that same form was me' with,
there should exist some guidance towards discovering the cause
of iis iiroduction. I have made not a few attempts from lime
to time, but was discouraged by the then impossibility of sufii-
ciently defining the curves that were dealt with. Thatdifticuliy
seems now removed To explain myself further, let us sup-
pose that a man finds the mark of a more or less incomplete
circle on the ground, and wishes to discover how it was
made. Various possibiliiies exist, which might have been
recorded lo help him: (i) The mark may have been
made by a basin, &c., turned in a lathe, or, what
come to the same thing in principle, by something revolving
round a fixed centre. f2) It may have been stamped by a
hoop, formed by bending an el.istic rod until its ends met,
the circular form depending on the equal distribution of stress.
(3) II may have been the mark of a withy that had bound a
f*gg"l. which, after selling into shape, had broken away, the
circular form arising from the compressi m of the sticks of the
faggot within the smallest possible girlh. (4) It may have been

' "M.iihcmatic.il Contributions to the Theury of Evolution " (Pan ii.), by
Karl I'carion. Read at the Ro>'al Society, January 24, 1895.

Ihe mark of a warped sheet of bark, hide, &c., the circular
form of which depended on the unequal coniraclion of its
outer and inner layers. (5) It could have been made by a
projecting nail, near the angle formed by two straight rods
securely joined at one end ; ihe apparatus being caused to
slraddle and press upon two pegs in the ground, and moved in
Ihe only way possible under those conditions. Here the frag-
ment of a circle would be due 10 Ihe conslancy of the angle
subtended by the same chord. .A. catalogue of these and other
possibilities, which are numerous and include circular forms of
animal and vegetable growth, would certainly enlarge the
speculations of the observer as to the cause of the circular mark.
So It would be wiih ihc curves of which I spoke. Each form
of curve would be a serious study in itself: still the results
would gradually accumula'e, audit is reasonable to look forward
to a time when a set of such curves, each defined by Prof. K.
Pearson's, method, shall have been studied.

I venture upon one criticism as to the completeness of
his generalisaiion. Variation of ihe normal kind is sup-
pose 1 to be due to the combined eftect of (1) an infinite
number of causes, that are (2) equally likely to err in
excess or deficiency, and {3) that are independent of one
another. These three restrictions are removed in the
generalised curve, which bears a ceriain relation to the
uinomial point curve formed by the expansion of (/ -H q)"
when (I) « need not be infinite, (2)/ need not be equal 10 ?,
while (3) the binomial form which implies independence of the
conlriljuioiy causes, is modified. Now though the condition (3)
is removed, it does not, as yet seem to me that the supposition
which replaces it. and which is based on such considerations as
\ ihe effect of withdrawing r cards from a pack of ns cards
> containing s suits, is analogous to what commonly occurs in
rerum natiinu Namely, the intermingling of contributory
cause; of various degrees of cfliciency, some of which are very
lew in number and have large efTects. Thus the number of
persons who walk day by day down St. James' Street, is
occasionally vastly augmented by some national spectacle, and
it is considerably and irregularly affected by changes in the
weather. It does not wholly depend on a multitude of equipotent
causes. So again, the time of ripening of the fruit on a tree
generally, is much afi'ec ed by the aspects of the pariicular
branches on which it grows. I thereiore conclude that the
effects of an aggiegate of large and small causes, ought to
be distinctly included in a thoroughly generalised formula of
variation.

Francis Galton.

NO. 1318, VOL. 5 l]

The Kinetic Theory of Gases.

I THINK sufficient stress has not been laid on the distinction
between the purely mathematical proof of the fundamental
determinantal relation connecting the differentials of the co-
ordinates and momenta of dynamical systems and the purely
statistical applications of that relation which form the subject
of the Kinetic Theory.

The well-known determinantal equation is perfectly general
and applicable to any dynamical system whatever. It merely
asserts that if the initial coordinates and momenta receive any
small independent variations whatever, the resulting variations
in the fiiml coordinates and momenta after any fixed interval of
time are so related to them that the dift'erential product of the
former variations is equal to that of the latter, conformably to
the well-known laws of Jacobians, by which the_variables are
changed in a multiple differential or integral.

In general the variations in question are purely hypothetical,
just as, in the principle of Least Action, the .actual motion is com-
pared with varied motions which have no real existence. If,
for example, we consider the system to be the Karlh, the
variations could only be made real by making the Karth move
dilTerently to what it actually moves, and doing this in every
possible w.ay.

]'>ut when it is required to assign any physical meaning to the
determinantal relation, these hypothetically varied molious must
be represented by actual motiims, and this can only be done by
taking an indefinitely large number of independent systems, all
simikar to the one we started with, and setting them moving in
all possible ways. The determinantal relation then tells us
tluit if the coordinates and momenta of these systems are
initially distributed according to what in my Report I have called

i20

NATURE

January 31, 1895

the Boltzmann-Maxwell dislribuiion, they will be so distributed
al acy subsequent instant. But in the absence of collisions or
encounters between the sysiem , thi< distribution will iiot be
unique. There exist o her distributions equally well satisfying
the condition of p rmanence.

The case of I wo or more molecules of gas in the process of en-
ciunier can be deduced, a-^ shown in my Report ;i3°'> ''y taking
each "system "to rcpres-nt a pair ot molecules, there being
at every instant an indefinitely large number of such pairs
having difTerent coordinates and mo-nenla. It now seems
definiely settled that if the molecules are rigid bodies, the only
possible permanent distribution unaffected by encounters is the
BoltzmtnnMaxwell distribution combined with motions of pure
translation and pure n tntion of the mass of gas as a whole
{Report. §46).

Many writers have limited their investigations to the case
where all the encounters are binary, and I see that Prof. Fitz-
gerald has emphasised this point in his recent letter. I do no' think
this is the right place to diaw the line. I can see no difficulty
in talcing account of encounters between three, four, or more
molecules, provided that such encounters are suHiciently nu-
mcrojs 10 have a law of distribution. Where the line mu-t lie
drawn is indicated in my Report. S 30(iii.l The molecules
which act on one another in any one encounter must form an
infinitesimal fraction of the whole mass ol gas, or the gas must
at any instant be divisible into an infinitely large number of
independent molecules and groups ui molecules, each molecule
or group thus constituting for the time being a free system by
itself. When the mo'ecules act nn each other at all dislarces,
orii is impossible to divide them intosmall independent gi cups,
the whole o' our theory breaks down.

It IS this limitation which, to my mind, precludes our apply-
ing the Kinetic Theory in its present state, nol only to molecules
moving ai'Oiit in a continuous medium, such as the ether may be,
but also to -olids and, probably, lii|uid-.

A good ileal of confusion has, I fear, a'i en with regard to
what 1 have called Maxwell's La* of Paitition of Kinetic
Energy, i.e. the statement that "if the kinetic energy of a
sjstem be expressed as a sum of squares, the mean values of these
squares are equal," from the fact ihat the term "■mean -mltic"
may be taken to represent "lime average for a single system " ;
and I fancy this may be the point Prof. Fitzgerald had in view
when he a-ked if the conclusions would not apply to the Earth
or a " finite number of particles moving about for an inde-
finitely long time." It cannot be too strongly emphasised that
this interpretation of mean values involves assumptions which
have hardly been sufficiently justified in any general class of
cases, and which have been repeatedly pioved to be invalid
in simple case; (Report, §S 9-12).' To give a simple (if not
quite analogous) illustration : suppose that on drawing counters
oat of a bag, we were to obtain on the average an equal number
of red, white, and green counters. We should not be justified
in inferring that if we kept a single counter sufficiently long
it would change colour and become in turn red, white, and
green.

As an illustration of a case where the Bollzmann-Maxwell
Law is inapplica'ile, consider a sphere of density a moving in
a perfect liquid ol density p. The kinetic energies of the
sphere and liquid are in the ratio of o- : J p, as we know from
hydro<Iynamical considerations, and the same is true for any
number of spheres whose distances apart arc very large com-
pared with their r.idii. This is not a case where nn transference
of energy lakes place between the sphere and liquid, and it is
not therefore open to Prof. Fitzgerald's objection to the case I
previou.tly cited. Whenever the motion of the solid is varied,
energy n transferred to or from the liquid.

If a iiif.eoii; ether will satisfy the requirements of physicists,
then the Bultzmann- Maxwell Law is uiidiubtcdiy applicable to
the elher. If not, the ether falls entirely beyond the scope of
our investigation. The Kinetic Theory is obviously a theory
framed to account for one class ol physical phenomena only,
viz. the thermal properties of gases. If any observed pheno-
mena are not deducililc from the results of the theory, it is to
my mind iufTicient to *how lhat this is because the funda-
menial assumption* of the theory are not satisfied, i.e. that the
phennncna in queslioD are not incomiilenl with the Kinetic
Th-o.y. G 11 liuvAs.

Pelerhousr, Cambridge, January 16.

• Se« al«n Natchr. January 10, p. 162.

NO. I318, VOL. 51I

Boltzmann's Minimum Function.

I SAID in my first letter on this subject that the condition .\,
on which, or its equivalent, the proof is based, could not apply
to the reversed motion. As that assertion has been questioned,
may I confirm it thus?

The initi.-<l distribution of R, the relative velocity, i.e. the
number of pairs of spheres for which it has given direction, is
arbiiriry — condition .\ is fulfilled. Then, as proved, whatever
the initial distribution, after collisions, the distribution of R is
uniform, i.e. all directions equally probable. Now reverse the
velocities. If condition .\ is fulfilled in the reversed motion,
then after the reversed collisions the distribution of R isuniforni.
It is equally certain that it must be the same as the initial dis-
tribution.

If, therefore, condition A is fulfilled in the reverse motion
as well as in the direct, that can only be because the dis-
tribution of R was uniform to begin with. But that means that

/f-T
H was minimum to begin with, and therefore ' = o through-

dt

out.

Lioltzmann's theorem can be applied 10 both motions only on
condition ;hat it h is no effect in either.

I New-square, Lincoln's Inn. S. H. BURiiURV.

Electroscopes in Lecture.

I Si;ppoSE teachers still use gold-leaf electroscopes for their
junior lectures ; certainly I have Tiund nothing else so dead-
beat, or so readily understood ; and by projecting with a lens a
shadow of the leaves on a square-foot translucent screen, the
movements are perfectly visiole to a l.irge audience by d.iy-
light. But the one objection 10 the instrument, when usei! f'>r
explaining the fundamental facts, say, of induction, is ih. 1 it
ini.!icates similaily positive and negative potentials. \'ester,iiiy,
however, my assistant, Mr. L. E. Robinson, ingeniously stood
the metal cased instrument on a cake of paraffin wax, and'
electrified its outside negatively. By this process the zero of ■
deflection is changed ; the leaves stand apart for zero
potential, diverge m >re for positive, and collapse for ne^'itive.
A zero sh.adowpoinler and rough scale may be readily u^c.l ;
and I propose now to mount a projection electrost pc m i
suitable slightly charged Leydea jar, whose outer cnat can then
be treated as the usual earthed terminal of the instrument,
whose case is connected to or formed by the inner coat of the
jar. The insulated or variable terminal is conveniently arranged
as an insulated sphere or other shaped body on the lecture
table, not far from the small screen, attached by a long enough
thin wire to the leaves — of which it is perhaps best to have only
one movable. Oi.i\ kr J. LoDCi;.

January 25.

The Perseid Meteors.

Your interesting rcference(NArURli, January 24, p. 30i)toUr.
Bredichin's investigation of the Perseid shower, induces mc to

t ofiTcr one or two remarks on the subject. In the paragraph alluded
to, it is staled lhat the radiant was observed from July 22 to
September 12, 1893; but Ibis long duration cannot possibly refer

I to the same system as that which furnislies the abuiulaiii maximum
on August 10. It is true there arc r.idiants in Peiseu^ in Sep-
tember, and the succeeding months of October, November, and

j necembcr supply many others, but, after the end of ihe third
week in August, nothing is seen of Ihe real Perseids. I cannot
say exactly on how many nights the display continues active, but
it IS certainly vi-ible fruiii July 19 to August 18, and the diurnal
motion of the radiant is about 1° lo the E.N.E.

There are really very few of the liue Perseids seen after
August 12, for ihe shower dies rapidly away after the maximum.
On August 15, 1893, during a walch of ihice hours, I saw only
oae Pels i I. On August 16, 1893. cluring a Nvatch of 4^ hours,

I I noted only four Perseids. I mention these facts lo prove the
extreme leniiily of ih' stream at the middle of .\ugiisl. But
there arc ditVerenccs from vcar to \'ear. An observer watching
the heavens for a similar interval on the same dales in succeciU
ing years will gel a varied experience. Thus one year cannot
be regarded as Ihe criterion of^ all.

Some years ago I recorded a few swift .slreak-lcaving melems
between August 19 and 24, from a railiant at 78° -(- 56" on the
northern borders of Auriga, and supposed they might be late

January 31, 1895 J

NATURE

321

Perseid?, but subsequent observations have convinced me thit
they hid no relaiion with the great August shower. They prob-
ably formed the early mem' ers of a welldelined raihant of
September Aurigidi which I found at 76° + 56° in 1879, and at
77° + 57' in 1885.

It appears to me that observations of the Perseids, and of
other meteor showers, are often undertaken and discussed while
losing sight of a most important circumstance. I refer to the
necessity of thorough training on the part of the observer, before
he can possibly hope to attain a high degree of precision in re-
cording meteor paths. Many month , if not years, of diligent
practice are required to render the observer proficient, and even
then there are many students who, being deficient in natural
aptitude, will never succeed in the work. It seems to be the
fashion at certain observatories to set a number of observers
(some of whom have perhaps never registered a meteor path
before) watching and recording meteors, and then to investigate
their results as though they could be thoroughly depended upon.
Such results are, however, pr.-ictically useless when emploied to
test any complicated point in meteoric astronomy. It is simdar
to placing a man, who has never played in a cricket match be-
fore, as wicket-keeper to fast bowlers like Mold, Richardson,
and Woods, and expect his performance to be creditable ! In
meteoric astronomv, as in many other spheres of action, skill is
only to he a-quired by long practice ; indeed, it is difficult to
single out any other branch of observation where the e\e and the
judgment have to be so quickly and accurately brought into play
to afford the best results. W. F. Denning.

Bristol, January 27.

The Artificial Spectrum Top.

In the interesting letter; on the above subject, which have
recently appeared in Na 1 itre, there does not seem to have
been any reference to the experiments of llelmholtz, as de-
scribed in his " Handbuch der Physiologischen Optik." 1866,
§ 23. He describes the facts in minute detail, and illustrates
them with numerous diagrams.

One important point not yet referred to, and described in
detail by Helmhollz, is that if a disc, marked with black and
white sections, be rotated with a certain rapidity, the field
appears to be covered with a pattern composed of hexagonal
spots ; at the part of the field of vision corresponding to the
yellow spot, a transverse oval figure is seen. In the centre
of this figure is a dark spot surrounded by a black circle.

Each of the hexagonal spots is dark with a lighter spot in the
centre, and surrounded by a red thread, which appears to be
moving in minute drops. The field seems to be pervaded
by a greenish hue, which flows towards the yellow spot.

These experiments, which I have verified on every point,
have a vcy important bearing on the photochemistry of the
retina and on colour vision.

Hendon, January 26. F. W. Edriuge-Green.

In reference to your Belfast correspondents' interesting
experiments with the artificial spectrum, which were long ago
included in my own experiments, a little reflection will show
that when the speed <pf rotation is increased, we do not retain
unaliercci the resultant proportion of stimulus an-i anti-stimuli's
on ihe retina. With a slow rotation we hive simultaneously
on the retina a persistence image of the lines and a real image
of ihe white card. When the speed is greater, we get simul-
taneously llu-se two, and in addition a persistence image of the
white card. Hence, according to my theoi)', ihe rise in scale
wi'h increased rapidity of revolution.

Colchester, January 26. CHARLES E. Benham.

Snake Cannibalism.

The reading of a paragraph and a letter printed in the
Mail for October 24 and 29, reminds me of a case of one snake
swallowing another, the consequences of which I witnessed.
While engaged in running a survey line for a railway across a
wood in this district, I noticed a snake close to me, doing
its best to get out of my way, but almost unable to do so. One
of my men struck at its neck with his " macheti," and suc-
ceeded in cutting the snake's head clean off. Immediately, to
our great surprise, another snake of the same species slowly
emerged head first, and, after a few struggles to escape, remained

NO. 1318. VOL. 51]

motionless on the ground ; a gash in its cranium, which had
been cut by ihe same stroke that killed the larger snake, being,
no doul)t, the cause of death, as the body was otherwise intact.
A measuring tape shiiwed that the larger snake was 6 feet in
length, and the smaller 5 feet. In this case the snake was
swallowed tail first, and therefore it seems highly probable that
the larger snake simply devoured it, and did not commence by
trying to dispute a portion of food, such as the pigeon and frog
cited in oihir instances. H. Tsnagal.

Sancti Spiritue, Cuba, November 23, 1S94.

More about Moths.
^^Communicated by ProJ. S. Garman, of the Museum of Com-
parative Zoology, Cambridgf, U.S.A.)

I.N Nature for December 6, 1894 (p. 127), Mr. Henry Cecil
publishes a criticism on a previous letter of mine, which I
cannot accept without a few words of remonstrance. His
explanation may be correct in part, but it certainly does not
cover all the ground.

That resistance alone is not necessary for the expansion of
the wings of moths, may be inferred from the fact that they will
often expand after an interval of several days, when the moths
have been prematurely released, the irregularity in outline
arising, I think, from the evaporation of moisture from the
wings, and in the consequent loss of elasticity. If the newly-
hatched insects are confined in a warm moist box, this trouble
seems to be obviated in a large degree, and the wings occasion-
ally attain to nearly the normal dimensions.

In raising moths artificially, it cannot be assumed that the
lack of proper pressure is entirely responsible for the frequent
occurrence of cripples.

All the conditions of feeding, moisture, and heat, must first be
carefully considered, since departures from the normal, on any
one of these line-, might so lower the vitality of the insect, that
perfect development would beome impoisible.

The writer also speaks of the wings of the moth in the cocoon
as "folded and crumpled," a statement which is entirely at
variance with my own observations. In all the cases which I
have noticed, the wings are perfectly smooth and unfolded
from the first, the increase in size resulting from a true ex-
pansion, the nature of which has, so far as I know, never been
fully explained. L. C. JoXES.

Melrose, Massachusetts.

THE PHYSICAL SOCfETVS ABSTRACTS OF

PHYSICAL PAPERS FROM FOREIGN

SOURCES.

THE days when learning meant dead languages, and
science meant collecting beetles, have passed
away ; science has grown and spread until it is impos-
sible for the most comprehensive intellect to grasp more
than a few twigs on its numerous branches. Organised
specialisation has become necessary to scientific progress.
Each subject now has its special society, and each society
has as much as it can do. Every sort of time-saving
arrangement is necessary if the workers in any one
branch of knowledge are to be kept informed as to what
Others are doing.

English chemists have long been supplied by the
Chemical Society with excellent abstracts of the current
literature of their subject, but up to the present the only
available work of the same kind on Physics has been the
Beiblatter of Wiedcmanris Annalen. .Admirable as
these are, it is impossible that a (German periodical can
fully meet the wants of Anglo-Saxon physicists. It is
therefore most desirable that abstracts of physical
papers should be published in English. The Physical
Society has now set itself to supply this want, and the
first number of the new volume of " .Abstracts "appeared
early in the present month. The Proceeilings of the
Society will in future be issued monthly, and the abstracts
of foreign papers on physics will be included under the
same cover. They will, however, be paged separately,
so that they can be bound separately at the end of the

322

NATURE

[January 31, 1895

year, when full indices, both to the subjects and the
names of authors, will be added. At present the Pro-
ceedings contain approximately fifty pages of original
matter, and fift>' pages of abstracts from foreign and
American sources.

It is an open secret that it is intended to enlarge the
abstracts later, so as to include English work. They
will then be an epitome of the work done in physics
throughout the world. The preparation of a large
number of abstracts on all sorts of subjects involves a
great deal of work and some organisation, and it is thus
better to be content with abstracts of half the extent of
those of the Chemical Society or the Beibldtter at first, at
any rate. The financial risk is also very heavy for a
society which is not rich, however energetic it may be.
The British Association has come forward with a helping
hand, and is aiding the Physical Society with a very
considerable money grant.

Mr. Swinburne has undertaken the office of editor.
He is assisted by a strong body of abstractors, many of
whom are recognised authorities on their own subjects,
and authors of well-known books on physics. In the
January number there are abstracts of 114. papers, of
which 25 are on General Physics, 22 on Light, 12 on
Heat, I on -Sound, 3+ on Electricity and Magnetism,
and 19 on Chemical Physics. The price to non-members
of the Society is two shillings and sixpence ; but as the
cost for a year at this rate exceeds the subscription to
the .Society, it is probable that the number of members
will increase for this, if for no other reason. It is hoped
that this will be so. Many branches of physics, unlike
chemistry and electricity, have no great industry be-
hind them. It is therefore necessary that all who care
for the study of pure physics should rally to the support
of the Physical Society in its new undertaking. The
meetings of the Society are now held in Burlington
House, in rooms hospitably put at its disposal by the
Chemical Society. They are held at five o'clock on
Fridays, so that persons who may come to town to
attend them, can afterwards go on to the Royal Insti-
tution. If an author so desires, the publication of his
paper will not be delayed for reading. Copies of the
paper are circulated before the meeting, so that the
discussion can begin early and with adequate know-
ledge. As soon as a paper has been read, an abstract
and a short account of the discussion is published in
Nature, in the Electrician, and other journals. The
paper itself is also communicated to the I'hilosopliical
Magazine, and is published with an abstract of the
discussion in the Societj-'s Proceedings.

THE NATURAL HISTORY OF
SOL IV A v.

THE

A LMOST all comers of the British Islands have been
•**• so thoroughly investigated by naturalists and col-
lertors, that I may be excused for directing attention to
one which seems to have been somewhat overlooked
the southern shore of Kirkcudbrightshire and Wigtown-
shire. I, at least, do not know of any work which has
been done there of late years. The Solway itself, so far
as I know, has received no attention at all— its shallow,
sandy character not offering much attraction to the
student of marine zoology.

Yet the surrounding district is, in other respects than
its natural history, an extremely interesting one -very
varied and beautiful in its scenery, secluded and quiet,
and out of the usual track of tourists; with many pic-
turesque and ruinous relics of a bygone age, abounding
in stream! and lochs suited both to naturalist and
angler, and associated incfTaceably with two, at least, of
Sir Walter Scott's finest works, "Guy Mannering" and
" Redgauntlet," to say nothing of the " Kiiders" of a

NO. 1318, VOL. 51]

more recent author, Mr. Crockett. It is, moreover,
easily accessible, and I suppose it is probably due to the
lack of hotels and other tourist accommodation that it is
so little known except to residents in the immediate
neighbourhood.

The bit of the district best known to me extends from
the estuary of the Nith — separating Dumfriesshire (rom
Kirkcudbrightshire — on the east, to the Water of Fleet,
which empties itself into Wigtown Bay, on the west.
This coast-line is of very diversified character, flat and
sandy eastward, where it has behind it a large tract of
marsh-land, the haunt of innumerable wild fowl, but
rising eastward into precipitous clilTs of sandstone and
limestone, which form in some places isolated pillars of
considerable height, and in others are hollowed out into
caverns, some of which are locally associated with the
name of Scott's piratical hero. Dirk Hatteraick. Some
of the streams notably the Water of Urr — come down
through a background of granitic hills, bringing with
them a vast amount of fine detritus which is deposited
on the sides of their estuaries and in the Solway itself,
round about their mouths. In such cases the natural
result is a very flat shore, composed of soft muddy sand,
stretching out very far seaward, and at low water un-
covered for stretches of many miles — a state of things
not unlike that which is found in the more familiar
Morecambe Bay at Grange-over-Sands. These muddy
expanses, when left by the tide, arc seen to be covered
with the contorted mounds thrown up by mnumerable
lug-worms, and so closely packed are these that there is
rarely a space of more than a few inches untenanted
by its worm. They form, in fact, quite a conspicuous
feature in photographs taken under these conditions, and
I do not doubt that the worms themselves, passing
through their bodies so much mud laden with de-
composing organic matter, which they thus absorb
and assimilate, contribute materi.illy to the sanitary
purification of what would otherwise become a
reeking, pestiferous swamp. Beyond these lug-worms,
1 am unable to say anything about the larger mud-
inhabiting fauna of the district. I thought it very
likely that Echinocardium cordatuiii and, perhaps,
Syiuipta might be found, as they are in some similar
localities in the Firth of Clyde, but the little time which
I spent in digging for them did not suflice to disclose
any specimens ; nor have I had any opportunity of
dredging in the Solway Firth. The water is shallow,
and the bottom uniformly sandy. 1 think it wouM be
sure to yield interesting micro/.oa belonging to such
groups as Copepoda and Ostracoda ; perhaps also
Cumacea and Slysid;i', but the absence of cast-up dt-l)ris
on the shore, either of the larger Crustacea or Moliusca,
seems to indicate a dearth of those creatures outside.
The littoral zone being chiefly of the flat sandy or muddy
character already described, there is not, except in
certain restricted areas, much opportunity for shore-
hunting of the ordinary kind. But, away from the" sphere
of influence' of the estuarine mud, there occur occa-
sional patches of inter-tidal rock with promising-looking
pools ; these are, however, fearfully storm-swept, and
incapable of alTording sufficiently secure attachment for
minyadherent animals. Afew common Hydrozoa,such as
SestiilitritrTinA Otm/>tiiiii/ari<r, a few patches of " Hydra-
tuba" and Ascidians were, 1 think, 'x\\\\ Alcyonidium
gclatini'suiii, 3.ho\\\. all that I noticed. Among swimming
things were, however, many Amphipoda and Copepoda,
and I took also several specimens of Afysis f.aiiiornce.
But my most interesting captures were made by washing
the muddy deposit found on the bottoms of some rock-
pools, and by netting amongst the weeds of pools situated
above ordinary high water-mark, though still subject
to occasional tidal influx. The Copepoda found in such
pools will be described elsewhere, but it may be noted
here that in some of the inland peaty pools and ditches

1

January 31, 1895]

NATURE

323

of the neighbourhood occurred an interesting; Oslracod,
Cydocypris globosa ; and in the White Loch, a species
still more interesting and more capricious in its dis-
tribution, Paiwinula Stevensoni.

As regards the botany of the district, 1 can say very
little. My last two visits were made about midsummer,
and at that time the sea banks were gorgeous with masses
of thrift and red cranesbill {Ccmniuir. sii>ii;!i!neii»i),
the marshy flats with golden fields of w;iter-tlag, the
fells with thickets of Rosa s/'iiiosissiiiia and numerous
orchids, the most conspicuous of which was the sweet-
scented species, Gviiinaden!,/ coiiofisen. These, of course,
are all flowers which cannot be overlooked, and are
an ever-present delight to the eye and mind : less
alluring species, which need to be hunted for, were for
the most part passed unnoticed, and such as 1 did gather
were of no particular interest.

G. Stevvardson Brady.

PROFESSOR ARTHUR CAYLEV, E.R.S.

MATHEM.'\T1CAL science has suffered a grievous
loss by the de^th of Prof. Cayiey, which occurred
on Saturday last, at Cambridge. There is hardly a
branch of pure mathematics which is not indebted to
him for original contributions of the highest vaiue, while
the important problems which have been elucidated by
him are so numerous, and cover so wide a field, that he
was certainly one of the greatest mathematicans which
the world has ever known.

It was in September 1S83, when Cayiey was President
of the lirilish .Association, that he was ranked among
our " Scientific Worthies," Dr. G, Salmon being his
biographer. We refrain, therefore, from giving a long
rotice of his life, and content ourselves with a Ltief
sketch of his scientific work.

Cayiey was born Augu-t 16, iy2i,at Richmond, Surrey.
At a very early age he showed great liking and aptitude
for arithmetical calculations. He entered King's College
School, London, at the age of fourteen, and three years
later went to Cambridge, where he entered Trinit\
College. In 1842 he came out as Senior Wrangler and
First Smith's Prizeman. Sir (Jeoige Stokes had been
Senior Wrangler in the previous year, and the late Prof.
Adams obtained the distinction in 1S43.

While still an undergraduate, Cayiey commenced his
career of mathematical publication by a paper in the
Cambridge Mathematical Joainal for iS4i,but it was
not until 1852 that he addressed a memoir to the Royal
Society, of which he was elected a Fellow in the same
year. Very soon after taking his degree at Cambridge,
he entered the legal profession, and was called to the
Bar in 1849. But during his career as a barrister, he was
constant to his first love, mathematics, and it was while
in legal practice that some of his most brilliant mathe-
matical discoveries were made. In 1S63, after fourteen
years of chamber life in Lincoln's Inn, he returned to
Cambridge to fill the newly-instituted .Sadlerian Pro-
fessorship of Mathematics, and no one could have been
better fitted than he to discharge the duties of the holder
of the chair, viz. "' to explain and teach the principles of
pure mathematics, and to apply himself to the advance-
ment of the science."

With regard to Cayiey as an original investigator, his
special merit has been described by Mr. (ilaisher. who
termed him "the greatest living master of algebra." It
is difficult to select the work for which he will be the
best remembered, but Prof. Salmon defined it as "his
creation of an entirely new branch of mathematics by
his discovery of the theory of invariants, which has
given quite a new aspect to several departments of
mathematics . . . .\nd the effect has been that the
knowledge which mathematicians now possess of the
structure of algebraic forms is as different from what it

NO. I318, VOL. 51]

was before Cayley's time as the knowledge of the human
body possessed by one who has dissected it and knows
its internal structure is different from that of one who-
has only seen it from the outside."

Among the honours which Cayiey received, may be
mentioned the Royal Medal of the Royal Society,
awarded to him in 1S59, and the Copley Medal in 1882.
He was a correspondent in the section of .Astronomy of the
Paris Academy cf Sciences, and was a Fellow or Foreign
Member of many other societies and academies, both at
home and abroad. He was given the honorary degrees
of D.C.L. by the University of Oxford in 1S64, and the
LL.D. by Dublin University in the following year.
Later, the University of Edinburgh conferred upon him
a similar honour, and he received the degree of Sc.D.
from his own University. The Universities of Leyden.
Gdttingen, and Bologna also conferred upon him the
degree of Ph.D. In 1890, the President of the French
Republic made him an officer of the Legion of Honour.
This distinction was granted in consequence of a
request addressed to the French Minister of Foreigiv
Affairs by the President and other members of the
Academy of .Sciences.

Cayley's mathematical papers, commencing in the
year 1S41, have .ippeared in every periodical mathemat-
ical publication of importance in Europe and America.
In the year 1887 he undertook the work of editing the
series of ten quarto volumes, in which the Syndics of the
Cambridge University Press are publishing his collected
mathematical papers. The publication of these volumes
commenced in 1889, and six of the volumes were re-
viewed in these columns a year ago (Nature, January 18,
1S94). The number of papers which appear in the six
volumes is 416. Altogether seven volumes have as yet
appeared. As Cayiey is responsible for 724 titles in the
Royal Society Catalogue down to 1883, and he has since
produced a considerable amount of mathematical work,
it seems improbable that ten volumes will be sufficient
to contain the results of his prodigious activity and
enormous literary industry.

What more need be said about this great master of
mathematics.- He sacrificed prospects of advancement
in the law in order to follow the mathematical work to
which he was devoted. He had the power to teach, and
the ability to extend the boundaries of knowledge. He
was " as distinguished for the amount and universality of
his reading as for his power of original work." Truly,
his memory will " outlive the life of dust and breath."

The funeral service will take place in the Chapel of
Trinity College to-morrow (Friday). Lord Kelvin will
be present to represent the Royal Society, and other
men of science will probably attend to do honour to the
memory of their brilliant fellow-worker.

NOTES.

We are enabled to stale that the communication to the Royal
.Society on " Argon, a new Constituent of Air,' by Lord Ray-
leigh and Prof. Ramsay, to be given at the Royal Society
today, will refer to the density of nitrogen from various
sources : to methods for removing free nitrogen from air ; to
the separation of argon from air by ditTusion ; to the density of
argon ; to its spectrum (on which a short paper will be read by
Mr. Crookes) : and to its behaviour at low temperatures. It is
interesting to note that Prof. 01szew>ki, of Cracow, has lique-
fied and solidified the gas, and will communicate a short paper
on the subject. The solubility in water is also recorded.
Various attempts to induce chemical combination are described,
and general conclusions arc drawn in a final section. The
ratio of its specific heats shows it to be a monatomic gas, and
proves that its atomic weight is approximately 40. The
meeting will not be held in the apartments of the Royal Society,
but in the theatre of the University of London.

324

NATURE

[January 31, 1895

Tub metric system of weights and measures is to be intro-
daced into Tonis OD March i.

Dr. Bredii'Hin has resigned the Directorship of the
Pallcova Observatory, on account of ill-health.

Dr. E. Ki \J., Protessor of Physiology in ihe University of
Marburg, has just died. lie carried out a number of important
researches in physiological and pathological chemistry.

Sir James Cockle, who held the post of Chief Justice of
<.>ueensland from 1862 to 1S79, died on Monday, at the age of
seventy-six. He was elected a Fellow of the Royal Society in
June 1865.

Prof. Lewis R. Giubes, of the College of Charleston,
South Carolina, U.S.A., whose death occurred towards the
end of last year, was born .\ugust 14, iSio. He was a
Professor in the above-mentioned College for more than
tifty years, from 1S3S to 1892 ; at first as Professor of Mathe-
matics, afterwards of Astronomy, Chemistry and Physics.
Prof. Gibbes published a number of articles on .islronomy,
natural historj', &'C., in various journals and in the pu^ilica-
tionsof scientific societies.

It will be remembered by our electrical readers, that at the con-
test organised by the City of Paris in 1889 for the best electric
meter, Prof. Elihu Thomson was awarded the prize of five
thousand francs. Desiring that this sum should serve for the deve-
lopmentofthelheoretical knowledge of electiicity, Prof. Thomson
arranged to offer a prize for the best work on one of four impor-
tant questions in electricity. The papers had to be sent in by
the middle of September 1893, but the decision of the Com-
mittee organised to adjudicate upon them has only lately been
made known. Four memoirs were received, one written in
German, one in French, and two in English. It was decided
that each of the two memoirs in English deserved the prize.
One was by Dr, .-\. Webster, of the Clark University, Wor-
cester, U.S.A., the subject being "An experimenial deter-
mination of the period of electric oscillations." The subject
of the other memoir was " An eximtnation of the absolute
accuracy of the formula for calculating the period of free oscil-
lation of a discharge condenser under circumstances such that
the resistance of the circuit has noappreciaMe disturbing effect."
This memoir dealt practically with a determination of " ri "
by a method of free oscillations, and the authors were Prof. O.
Lodge and Mr. R, T. Glazebrook. Ultimately it was decided
to award a prize of five thousand francs for each of these
papers, the money fir the purpose having been collected.
The collection of the additional money caused the delay in
the publication of the decision of the Committee.

The opinion has often been expressed that corn or at least
grass could be profitably cultivated on Ihe high plateaux of
Norwa). Dr, Hans Reii'ch, the Director of the Norwegian
Geologrcil Survey, concludes, however, in a recent publication,
that the loil which once existed, was nearly all scrapcdaway
daring Ihe Ice Age, and that cultivation could not now be
carried on wilh much success.

The Royal Photographic Society, which became incorporated
on January I in this year, have iletermined that the Society
shall hereafter con«i«l of two clasic<. Members and Fellows.
la future, m members will be admitted to the fellowship until
they have given the Council satisfactory proof of the possession
by them of suitable .laaliftcations for the litle F. R.P, S.,
which in thii way will become a guarantee of ability on the part
of it* holder in cither scientific or artistic photo^>raphy.

DCRINO Ihe past week, snow has filirn over all parts of the
Rriliih ('lands ; in Scotland and the north of Ireland the
amounts have been large, and even in the Channel Islands a

HO. 1318, VOL. 51I

depth of six inches was recorded. Very sharp frosts have also
been experienced in all parts, and for some days the ther-
mometer in places has not risen above the freeninjj point. The
following low readings have been notified to the Meteorological
Office : S'at Lland iviry, on the 2ith ; 2° at llillington (Nor-
folk), and 11° at Varmouth, on the 27th: and 9° at Lough-
borough, on the 29lh January. At H.ipar.nnda, in the Gulf of
Bo hnia, a temperature of - 24' w.is recorded on January 26
and 29, and over Europe gen;rally the weather was very cold,
frost and sn )w occurin^ as farsniihas Nice and Biarritz. A
den^e fog occurred in London on the afternoon of January 29.

TuEtwenty.f'ifih anniversary of the transfer of the telegraph
to the State in the United Kingdom was celebrated on Monday,
by a banquet at the Hotel Mctropole, under the presidency of
the Postmaster-General, Mr. Arnold Morley. The very re-
markable developments of telegraphy during the last quarter of
accniury is shown by some statistical information furnished to
the guest-;. The telegrams have risen from 6,Sjo,ooo to
71,465,000, the mileage of line from 14,776 to -32,881, the
mileage of wire from 59,430 to 206,304, the instruments in
use from 670 to S500, the number of words per minute capable
of beinj transmitted on the fastest form of instrument from 70
to 600, and the offices from 2932 to 9637.

On Wedneslay, February 6, the Hon. T. F. Bayard, United
States .'Vr.bassador, will distribute the prizes to evening
students of the People's Palace, .Mile End Road, E.

The following are the names of the candidates who passed
the recent examination of the Institute of Chemistry : — -\. E.
Bell, C. S. Ellis, Dr. M. O. Forster, J, Lones, G. H. Russell,
W. H. Sodeau, W, L, Sutton, and W. G. Young.

On Thursday afternoon, February 14, Mr. L. Fletcher,
F.R.S., Keeper of Minerals at the British Museum, will begin
a course of three lectures at the Royal Institution on Meteorites.
The P'liday evening discourse on February 8 will be delivered
by Dr. G. Sims Woodhead, his subject being " The Antitoxin
Serum Treatment of Diphtheria. "

I.v accordance with the scheme recommended by the Royal
Commission, telegraphic and telephonic communication has
been established by the Post Office authorities in connection
with the Liverpool life-buat service and look-out sta'ions, and
also at various points on the Welsh coast.

According to the Paris correspondent of the /.<iiicet, a
survey of the statistics hitherto published in divers countries of
the results of the application of Behring and Roix's method in
ihe treatment of diphtheria up to the last day of December
1S94, gives a total of 2700 cases with 433 deaths, or a mortality
ol 16 per cent.

A GENERAL meeting of the members of the Federated
Institution of Mining Engineers will be held on Tuesday,
February 12, at 10.30 a.m., in the Examination Hall of the
Mason Science College, Birmingham. Arrangements have
been made for visits to collieries, &c., on the following day.

TllK third series of lectures arranged by the Sunday Lecture
Society begins next Sunday afternoon, in S'. George's Hall,
L.-ingliam Place, at 4 p.m., when Mr. A. Smith Woodward will
lecture on "The Restoration of Exiinct .Vnimals." Lectures
will subse<iuently be given by Dr. R D. Robert-. Prof.
Henry K. Armstrong, F.R..S., Mr. C. T. Wnitmell, Dr. C. W.
Kiuimins Mr. Douglas Carnegie, and Mr. W. Mayhowe
Heller.

The twenty-second annual dinner of the old students of the
Royal School of Mines took place on Friday evening;, at the
Criterion Restaurant, under the presidency ol Mr. W. H.
Greenwood. A large number of guests were present, among

January 31, 1895]

NA TURE

325

them being General F. T. Lloyd, Mr. Jeremiah Head, Prof.
J. \V. Judd, Prof. Roberts-Austen, Mr. H. A. Wig^in, .Mr. E.
Matlhey, Prof. W. A. Tilden, Prof. A. \V. Riicker, Prof. G.
3. Howes, Mr. \V, Gowland, Dr. W. P. Wynne, Prof. C. V.
Boys, Prof. J. B. Farmer, and Prof. A. K. Hunlingdon.

The following arrangements have been made for lectures at
the Royal Victoria Hall, Waterloo Bridge Road, S.E., during
February: Sir Colin Scott MoncriefT on "Egypt and the
Nile'' ; Mr. Smith Woodward on " -\ Visit, to Russia" ; Dr.
J. Norman Collii on " The Alps around Mont Blanc "; Prof.
Ramsay, F.R.S., on "Some New Discoveries about the Air."
This lecture will have special reference to the investigations
by Lord Rayleigh and Prof. Ramsay, which resulted in \\\t
discovery of a new constituent of the almoiphere.

The twenty-first general meeting of the Association for the
Improvement of Geometrical Teaching was held at University
College on January 19, Dr. R. Wormell, the Presiilent, in the
chair. The report of the Council, prop )sing the continuation
of the Mathematical Gazette, and the Treasurer's report were
read and adopted. Dr. Larmor, of St. John's College, Cam-
bridge, was elected President in the place of Dr. Wormell, who
retires ; the other members of the Council, including, the hon.
sees., R. Holmes (The Avenue, St. Margaret's, Twickenha'n)
and C. Pendlebury (53 Gunterstone Road, West Kensington),
were re-elected. .Vfter the elections, Mr. E. iNL Langley gave
some geometrical notes, and Mr. G. E. Heppel read a paper on
" .\lgebra in Schools." .\fter an adjournment. Dr. Larmor
took the chair, and papers were read by Rev. C. Taylor (" The
A. \. G. T. Syllabus of Geometrical Conies ") and Rev. J. J.
Milne ("The Conies of .\pollonius"j, and Prof. Lodge gave
some notes on Mensuration. Interesting discussi ins followed
these. All communications with respect to the Mathematical
Gazette %\io\Ad, be addressed to the Editor, 16, Adelaide Square,
Bedford.

Colonel A. T. Eraser, writing to us from Bagdad, says
that while travelling lately on the right bank of the Euphrates,
he noticed a pair of caves near the usual black woollen cloth
tent lived in by the -Vrabs, and found that, as evening drew in,
a number of cows were driven down, and the caves shui with
plugs of straw and thorns. " It was evident," he says, " that
this must have been the primary use to which those early types
of man of the dint and bronze ages, about whom we know so
little, put the so-called cave dwellings, that of sepulture being
an after- thought. Une would imagine, reasoning hastily, that
cows and .-Vrabs should have more properly changed places.
But the .Vrabs bring the experience of thousands of years to
bear on this question, and prefer the free air to a confined
atmosphere suitable only to ruminant beasts, and tents to caves.
Having alluvial soil to deal with, the Arabs in this instance dug
pits about four feet deep, and domed over the top with brush-
wooci and straw to compLte the caves, the whole showing but
little above the surface. There was no need of permanence, as
encampments shift with the seasons. Under other circumstances
the old " cave ' races would have dug the entire cavity out of
the solid, but still put in their cattle, and remain outside them-
selves."

For some classes of observations involving the use of a
spectroscope, the movement of either collima'or or observing
telescope is objectionable, and for such work it becomes
necessary to rotate the prism in order to bring different parts
of the spectrum into the field of view. If the condition of
minimum deviation be of no importance, as in the case of Mr,
' Tutton's apparatus for obtaining monochromatic illumination,
there is no objection to turning the prism in this way, but if
the condition of minimum deviation for the central ray in the

NO. 15 18, VOL. 51]

field is to be retained, some special device is essential. This
has already been accomplished in various more or less elaborate
ways, but Mr. F. L. O. Wad^worth has now indicated a means
of satisfying this condition very simply {Astronomy an i Astro-
physics, December 1894). The general solution of the problem
is effected by the introduction of a mirror into some pan of the
spectro-copic train between the slit and the focal plane of the
observing lens, the mirror having an angular movement equal
to one half the change in angular motion of the ray refracted
at minimum deviation. The mirror may be disposed in several
ways, but that finally adopted for use with the speclro-bolo-
meter is to place it in continuation of the back face of the
prism. With this arrangement the emergent ray is parallel to
the incident one, so that a direct vision spectroscope is obtained
by the use of a single prism. The prism and mirror are
together m lunted on the graduated circle of the spectrometer,
and by making the axis of rotation of the system coincident
with the intersection of the plane bisecting the refracting angle
of the prism and the plane of the mirror, there is no lateral
displacement of the ray at minimum deviation. The idea
seeiiH to be an excellent one, and capable of wide application.

That gales have a considerable effect upon the heights of
tides is very well known. The gale of January 23, furnished
an example of this at the East India Dock, .\ccordiiig to a
letter in the Times, high water was due at the Dock at
I2'46 a.m. on January 24. At ten o'clock on the previous
evening, however, the tide had risen three inches above
Trinity datum, and then fell 5 feet 4 inches to midnight.
It again rose five inches to i a.m., when it went away
altogether. The phenomena suggest that, probably, the
records of self-registering tide gauges, when discussed
in connection with high winds and cyc'ones, will furnish
useful results. Prjf. Cleveland Abbe notes in the Monthly
Weatlitr Review that, during a hurricane at Charlest-jn last
September, the excess of the actual over the normal high water
mark increased gradually until it reached more thsn five feet.
I In this connection some observations on the indication of dis-
tant storms by tides are of interest. Captain E- Jones, who for
many years kept logs of deep-water voyages of Lieutenant
Maury, states that, previors to a cyclonic storm which
occurred early in September, he no. iced that at low water the
tide did not fall near as low as under ordinary conditions, and
he came to the conclusion that a cyclone was approaching, as
he had noticed before that under these conditions such storms
are very certain to mike their appearance. He testifies " that
this abnormal condition is an infallible indication of a storm
approaching or passing by. .-V storm directly in from seaward
generally affects the Hood tide even more than a low water
tide, but in the present case the high water was about normal.
A long experience gives me great confidence in the barometer
as affording valuable prognostication of a storm, but this tidal
wave along the coast preceding a cyclone must, as it seems to
me, give abioliue proof that some kind of storm is in progress ;
the astonishing thing is that the ocean level is aft'ected by the
cyclone at such a great distance, and especially ahead of it."

In the American Engineer for January, Prof 11. A. Hazen
gives some of the results of a very interesting balloon ascent
made in the "Svea"at Stockholm, by S. A. Andree. The
account is taken from the Procceiiings of the Swedish .\cademy,
vol. 20, part ii. , No. 3. The balloon travelled for 136 miles east
over the Ualtic, the highest point reached being 9900 feet, and
at the time of the ascent, Stockholm was nearly in the centre of
a high barometric area ; this fact, in connection with the posi
tion of the balloon over a wide, expanse of water, adds great -
interest to the observations. The diminution of temperature
with height, allowing for increasing heat during the day, was

326

NA TURE

[JANUARY 31, 1895

aboot r in 250 feel, in the first 4000 feet, which is noteworthy,
iS the se» surface causes less diminution with height. Above
4000 fee!, clouds were encountered, and these changed the rate
of diminution, while at the highest 'point, the result was V in
400 feet. The most interesting feature is the gre.it dryness of
the air above 7500 feet ; at 6000 feet the relative humidity was
100 per cent., and at iSoo feet higher it was only 4 per cent.
Prof. Hazen states that this is the ra^st extraordinary fall in
humidity ever observed, and it shows how little we really know
of atmospheric conditions, even at very low heights. The value
of the results to be obtained by balloon ascent; in determining
the laws of storms is beyond doubt, and Prof. Hazen strongly
advocates that such researches should be undertaken.

The origin of the .\lpine Serpentines has always been a
subject for wide differences of opinion. The Italian school of
geologists until lately upheld the view that they were metamor-
phosed sedimentary rock-!, while English and German geolo'^ists
maintain their intrusive nature. O.ie of the latest contributions
to this subject comes from Dr. Ernst Weinschenk who, in the
Abhandtun^en of the Bavarian Academy of Sciences (Munich,
1891) describes the occurrence and petrography of the serpen-
tines of the Great Veneiiger, a mountain in the Eas'ern Alps of
North Tyrol. He tinds that -they are undoubtedly intrusive
rocks, formed by the consolidation of a peridotite magma that
wa» squeezed in between the foliation-planes of the neighbour-
in;; mica-schists during the great Alpine earth-movements.
They thus occur as a series of laccolites (/jw.v/;), which, we
mav observe, resemble in their origin those i)f Shropshire rather
than the typical laccolites of the Henry Mountains, which were
intruded into horizontal strata. After their first consolidaiion,
the peridotites were crushed by the continuation of the earth-
movements, and by the continued action of superheated vapours
and solutions were gradually converted into their present con-
dition. The evidence of these changes is seen in the minute
structure of the rocks, which, as well a; the nature of the
melamorphism they have produced in the surrounding schists,
is eichausiively described in the paper, and illustrated by a
number of micro-photographs.

deals with the gneiss
These have also been

A SECOXt) paper, by the same author,
and granite of the same part of the Alps,
studied by Prof. L<i«l, whose results are published in the
Verlaf;der k.h. ^eol. Mcichsaii^lall {\"\enn&, 1894). Thisauthor
treats the subject from a sirucluril point of view, and his
memoir is illustrated by a map and several sections ; while Dr.
Weinschenk describes the petrography in detail. Both authors
assert the undoubtedly intrusive origin of these rocks, and
incline to class them with the pre-carboniferous " Prologine "
of the Western Alps. Dr. Weinschenk regards certain
peculiarities in the granite as due to lateral pressure during the
period of consolidi'ion, and proposes the term I'iezocryilal-
litalian for the development of structures under such conditions.

TilP. elasticity of solid gelatine solutions is the subject of
an investigation by Erwin Fraas, in Wiedemann' s Annalen.
Sticks of aqueous gelatine were obtained in the following
manner. Brass tubes, about a foot long and half an inch thick,
were cut in two at the centre and joined by wire rings. They
were closed at one end with a cork, and were placed vertically.
The gelatine solutions were then poured in, care being taken
to prevent adhesion by rubbing with olive oil. The suspension
of the slicks was a matter of some difficulty, but it was accom-
plished by brass clamps of the shape of a cylinder, cut along
ill length on Imth sides and roughened inside, which were
gently pressed on the gclaline by a spring. It was found that
io no case did the volume change by stretching, the diminution
girth lieing compensated by the increase of length. The
NO. I318, VOL. 51]

addition of common salt impaired the elasticity and strength ot
the sticks very considerably, making them unlit to support a
pound -weight, while part of the water could be replaced by
glycerine, cane sugar, or gum arabic, without making any
difference.

Thi; Comples-rendiis of the Paiis Academy, of January 14,
givean account of some modifications of anelectrical anemometer
for metly used by the Rev. Marc Dechevrens, at Zi-ka wei, for
recording the horizontal and vertical movements of the atmo-
sphere. The instrument, which is being constructed by M.
Richard, is to be erected at the observatory of the Jesuit College
in Jersey, and possesses some novel contrivances intended to
ensure its satisfactory performance. The fan of the anemometer,
which gives the horizontal component, is formed by portions of
a cylinder ; this arrangement was devised hy M. Dechevrens,
and is said to give excellent results. There is also an arrange-
ment which assures sufficient duration to the electric contacts,
to excite the electromagnets, while preventing prolonged
contacts, which exhaust the batteries without doing any good.
Two wires out of seven which exist in similar instruments are
dispensed with ; this is also an important simplification if the
registrations are to be recorded at a distance.

The current number of Wiedemann's Annalen contains a
paper by Max Weber, on electromagnet pull. The author has
measured the pull exerted on a long iron wire, one end of which
projects within a helix, when a known current flows through
this helix, producing a magnetic field of known intensity. The
wire under examination is suspended horizontally by four silk
fibres in the same way as in a ballistic pendulum. The dis-
placement of the wire under the action of the coil is meavured
by means of a microscope, and from a knowledge of the weight
of the wire and the length of the suspending fibres the pull can
be calculated. Ihe author has investigated the connection
between the pull per unit cross-section of the wire {/„), the
strength of the field within the helix (H), and the intensity of
magnetisation (J), and finds that/,, = JH, when the length of
the wire is parallel to the lines of force of the helix, and the
diameter of the wire is very small compared with its length.
The author has also examined the pull perpendicular to the
lines of fore?, by uslnj two coaxial magnetising coils separated
by a small interval, the wire being placed with its length per-
pendicular to the axes of these coils, and its end passing through
the space left between them. If the pull per unit area of cross-
section of the wire under these conditions is called/j., then
/± is always, in the case of iron, less than/,,. For fields having
an intensity ol a')out too, the ratio ///J- is about 100, but
decreases rapidly with increasing field strengths, and appears
to approach unity as a limit. Thus for H = 1 2,000 /„/± =I'II.

It is known that the direction of the pendulum line shows a
consideiabic anomaly around .Moscow. The line is deviated at
Moscow by lo"'6 to the north ; at Tsaritsino, in the south-east,
the deviation is only o '5 in the same direction ; and at Podolsk,
which is twenty-one miles from the capital, the deviation takes
the opposite direction, to the south, and auains - 2" "J. It has
been supposed that beneath the neutral zone, at Tsaritsino,
there must be great cavities in the rocks, or that the rocks,
as a whole, have a density below the average. We now learn
from a note by (General Stcbnitskiy, in the last issue of the
/zveslia of the Russian (Geographical Society (1K94, No. 4), that
the pendulum observations which have been made around Mos-
cow by M. Iveronoff, give full support to the above supposition.
The differences between the lengths of the second-beating pen-
dulum, observed and calculated, being positive at .Moscow and at
Podolsk ( -f 00108 and + 00064 millimetre-^ respectively), the
same difference is negative above the neutral z>ne uf Tsaritsino
( - o°o228 millimetres), thus showing a deficiency in the acceieia-

January 31, 1895]

NA TURE

327

tion due to gravitation to the amount of i/30,oooth of the
total force.

The last number of the Izvisiia of the Russian Geographical
Society contains a very interesting account of Baron Toll's
expedition to Arctic Siberia and the New Siberia Islands.
Baron Toll was sent out by the Academy of Sciences to examine
the body of a mammoth which was said to have been dis-
covered on the banks of the Balakhna, a tributary of the
Khatanga Bay, and altogether to continue the work which had
been entrusted to Chersky, but wa-; interrupted by his death.
Lieut. Shileiko undertook the surveys, as well as the astro-
nomical and magnetical oliiervation-. After a three months'
journey the two explorers reached the village Kazachiye, at the
mouth of the Yana, in 71' north latitude. A visit to the mam-
moth soon proved that there was nothing left but a few pieces
of skin with its hair clothing, parts of the extremities, and a
broken skull of a young mammoth. A number of remarkable
explorations and surveys, astronomical and magnetical obser-
vations, and geological explorations were, however, carried
out. The chief geological result is the settling of the real
positions of the layers which contain relics of the mammoth.
Tbey are undoubtedly Post-Glacial, as they overlie the masses
of underground ice which form the chief rock of the great
Lyakhoff Island, and which, as Baron Toll's observations now
prove, are remains of the great ice-sheet which formerly
covered both the islands and the mainland, and whose moraines
have now been discovered on the mainland. Moreover, these
ice masses have the typical granulated structure of the glacier
ice, which proves that they have originated from the snow-cover,
and could not have originated from any sort of running water.
.A.S to the Post-Glacial layers which overlie the above, they con-
tain, be-ides shells of Cyclas and Valvata and well-preserved
insects, full trees of Alnus friiticosa, willows, and birch, fifteen
feet high, .ind bearing perfectly well-preserved leaves and cones.
The northern limit of tree vegetation thus spread during the
Mammoth period full three degrees of latitude higher than it
spreads now, i.e. up to the 74th degree, and the mammoths and
rhinocerosesof the time lived upon the patches of meadow clothed
with the above bushes. It is worthy of note, that the masses of
underground ice are not found in the lower parts of the Arctic
coast which are known to have been covered by the Post-
Pliocene sea, and that they only occur where the land rises a few
hundred feet above the present level of the sea — that is, .above the
evel of the Post-Pliocene ocean.

After considerable delay, Murray's " Handbook for Hert-
fordshire, Bedfordshire, and Huntingdonshire" has been pub-
lished. Brief notes on the geology, botany, and antiquities of
these counties are given in an introduction.

The Matriculation Directory (No. xvii.) of the University
Correspondence College has just been received. It contains
the examination papers (together with solutions) set at the recent
matriculation examination, and also articles on the special
subjects for next June, and for January 1896.

The additions to the Zoological Society's Gardensduring the
past week include a Macaque Monkey (Macacus cynoiKol»us, 9 )
from India, presented by Miss Teresa M. L. Monteath ; two
Little .\uks(.l/i;/:i.'«/«ja//f) from Norfolk, presented respectively
by Mr. Hamon Le Strange and Colonel Feilden ; a Cardinal
Grosbeak {Cardinalii virgiitiaiiiis) from North America,
presented by Mr. F. Beresford Wright ; two Leopard Tortoises
(lesludo partialis), a Cape Bucephalus {Bucephalus capcnsis)
from South .\frica, presented by Mr. J. K. Matcham ; two
Mantells Apteryx (Aplery.x mantclli) from New Zealand, a
Black Iguana {Mctopoceros corniilus) from San Domingo,
deposited; a Hog Deer (CV/'J'K^ /;>;'< 7'/;K.t)t born in the Gardens.

NO. 1318, VOL. 51]

OUR ASTRONOMICAL COLUMN.

The Natal Observatory. — Mr. NeviU's report upon the
work of the Natal Observatory, during the fiscal year ending
last June, has been issued. The staff of the Observatory con-
sists of an astronomical assistant, a meteorological assistant,
and a computor, all of them ladies. In spite of such limited
assistance, much important work has been accomplished. The
observations of Mars during the opposition of 1892 have been
completely reduced ; and as soon as the corresponding observa-
tions made at the northern observatories have been reduced
and published, it is proposed to compare the two series, and
obtain from them a new determination of the distance of the
sun. .\ contribution to the knowledge M the variation of lati-
tude is included in the report. Since 1884 a number of obser-
vations have been made, by Talcott's method, to determine the
latitude of the observatory. The observations invite con-
sideration, on account of the fact that they were made and re-
duced before any special attention had been directed to the
variation, 'arising from the suspected periodical inequality, in the
direction of the polar axis of the earth. The mean latitude,
deduced from the 1023 oiiservations made during the six years
1884-1890, was 29° 51' 46"68. The results obtained, from the
separate observations of each year, show a steady gradual de-
crease since 18S5. The observed latitude of the Observatory
seems to have reached a maximum in that year, and to have
steadily decreased since, at a nearly uniform rate of o"-27 pel
annum. The rate of decrease up to 1890, however, appears to
have quickly diminished, indicating a periodical irregularity in
the apparent value of the latitude of the Observatory. Mr.
Nevill remarks that a great deal of important work has accu-
mulated at the Observatory, but the Government of Natal will
not afford the necessary facilities for printing and publishing it.

The New Dudley Observatory. — The disadvantages of
the old situation of the Dudley Observatory had long been
recognised, but it was not until 1892 that the generosity of
Miss Bruce and other " friends and neighbours of the observa-
tory," permitted the removal of the observatory to its present
more favourable site. From an account given by the Director,
Mr. Lewis Boss, in the Astronomical Jonrmil No. 334, we
learn that the observatory grounds consist of six acres,
situated in an area of about forty acres, designed to form part
of the paik system of the City of Albany. The buildings appear
to be all that can be desired, and many advantages will no
doubt be derived from the provision of dwelling accommodation
(or the observers. The Transit Circle provided in 1S57 has been
re-erected with sDme slight additions, and it is satisfactory to
learn that its large aperture of 0203 m. and focal length of 3
metres, is no detriment to its excellence. K new equatorial,
denominated the Pruyn, having an aperture of 31 centimetres,
has been presented by the sons of a former President of the
Board of Trustees. In this instrument, a photographic com-
bination is obtained by replacing the flint glass of the visual
telescope with a second one, and it is believed that this
arrangement will be a complete success.

No elaborate programme of work is promised, but " the logic
of events and inclination invites the observatory to undertake
the comprehensive observation and discussion of stars known
to have sensible proper motions." The Transit Circle will
ace irdingly be devoted to this work, and the equatorial will
take a subordinate place, " though it is expected that the
zealous young assistants will continue to give a good .account of
themselves in work with this instrument, so far as circumstances
permit."

The Milky Way. — Returning to the subject of the distribu-
tion of stars in the celestial sphere, C. F.aston {Ast. Nach. 3270)
has derived some results of considerable interest by limiting his
attention to twocompiratively small regions of the Milky Way,
one in .\quila, and another in Cygnus, the latter embracing a
specially daik as well as a notably bright region. For each of
these regions he finds that the general luminosity of the Milky
Way corresponds very much more closely with .Vrgelander's
stars of magnitudes 91 95, than with the siars of greater
brightness. .\ diagram in which all the stars of the Bonn maps
have been reduced to the corresponding number of stars of
mag. 9'5, shows very little similarity with the features of the
Milky Way. Extending his inquiries to the photographs taken
by Dr. Max Wolf, showing stars down to mag. 15, he shows
that the very feeble slats followed the same law of distribution

32S

.VA TURE

[January 31, 1895

.. .ho« of mies Qi-9-5. This correlation .ppears to indicate

*K-.i thr fainiest «:tars and those of the mn or lom nia^-
p'ot^bfy Kart of one sy.en,, and are »' "-^^ ':/,"-
His-ance from us At .he same t.me, some . '»" ^''I ?f^^\v *"
oth i.-ae -=e<:m to be intimately associated w.th '^e M Iky " ay^
'^The hypothesis of an annular sy.tem, relatively -obted rom
theceninS part of the Rreat galactic system is regarded as not

n^mpL™ble »ith the di-lribmion of stars «h.ch he has founC
F^" at nearly the same distance from us, stars vary so much
in sz"e or int-insic brightness as to give •""g"''"'^" ""^'"e
from 9 to 15. there seems no reason why some should not be of
creitcr bnuhiness than 9th mag. ,

* There is nothing to prove, however that the various par so
the Mdky Way .rl at an equal distance from us, nor even ha

.may be'^an enclosed ring. It does not ^PPear improbable .ha
sub«quent researches may show the ex.>t.nce of one or several
tu.raN emanating from a cer...al accumuUition, and recurving o
a^ .0 form a nearly annular sys.cm. or ore consisting of nearly
Toncentrk rings. Mowever it may he, Mr. Easu,n's r.sulls seem
r . S c" .e that the portion of the Milky Way accessible o

.mr ».eans of obser%a.ion. has but little thickness in relation .0

"In LTa^r en the same subject (AV-.W.*.. February^ Mr^
Maunder fiiidsit difficult to rc-ist the conclusion that the daik
Un. s- of the M.lky Way a.e really region- of barrenness, and
regards these features ..s indications of a process of condensa-
lion toing on in the stellar as well as in the . ebulous matter.

The Snstem of ALr.ot.—tJai.e recemly (Naturk, vol.
xlv p. 446) Mr. Chandler credited Algol with an oljscure com-
uanion in addition to that which was recognised l,y Coodricke,
r,!d .he existence of which has been fully confirmed .y the in
vstigaUons of Pickering and Vogel. Mr. Chandlers concl,..
lion^weie based on a discussion of the s)S,ematic 1, regularities

of the epochs of minima, and were ''Pl'J^'"!'^/!;" '''",'' E
, la.er discussion of Ibe proper motion nf Algol itseK (Nature,
vol xlix P -,49\ The evidence of irregular proper n.olion,
howe^er, il not legarded as conclusive by some aulhon.ies. and
M Tisserand, the Director of the Pans (Observatory, is ap-
parently one of the unconvinced, lie has therefore a<<e"ip ed
^Tlind fome other explanation of the phase variations (C.",//..-
AW«., January 21, 1895), and the result is to =^how .ha.
,hey can be simply and sufficiently explained by supposing a
single dark companion moving in =">,«"'p".\ '"^'"'^ °i ^,' ''
cular. orbit; and, in actdilion. that the bright star exh.bi.sa
sensible polar compression. The resul. of this depa.....e (rom
the spherical form would be a movement of the periastion point,
and ihi- would explain .he apparent iriegularines

Assuming that the plane of the orbit is coincidenl with he
equa.or ol Algol, its tccen.riciiy is found to be 0-132, and the
polar diameter is shorier ihan the equatorial by .U.

The consequences of these condiiions would be a very slight
variation of minimum brightness in the long period of 140
years, and an entirely negligible d.f.erence in the t.me "f Pas;'»H':
10 minimum and recovery of normal bngh.ness. I he to ai
duration of the eclipse, however, will vary very considerably
Taking .he mean epochs 1800 a..d 1SS4 for the observations of
Wurm and Schonfeld respectively, M. Tisserand finds that .he
duration would be increased in this lime by 1 63 hours, tiince
the lime^ given b. these observers are 6 5h. and QXih. respec-
tively, M. Tisserand is entitled to regard this as confirmation ol
hi%hypithesis. lie points out the importance of spectroscopic
obsctvalif.n* at short intervals from miminum, in connection
with his explanation. .. „ , .

The irregularities in U Ophiuchi and U Cephei are pro
biblyto be explained in the same way.

THE EXPLOSIVE NATURE OF THE SODIUM
AND POTASSIUM DERIVATIVES OF
NITIiOM ETHANE.
COMK additional inloni.alion cf an inlereMing char.icler con-
'^ ccining the extiemely explo»ivc sodium and polas-iuin
compounds of nilromctliam-, is contributed to the current
Jlnirhltoi ihe German Chemical Society by Prof. Zclinsky ol
Mo-cow. A thoil lime ago Prof. Vict ir Meyer dt«cribed
(lUricliU, 27, 1601) a mode of preparing the sodium compound
CH,NaNO, in a «l.-iie of purity. The process consists in dilut-
ing a quan ily of nilromelhane. CHjN< >,. wi.h clhcr and treat-
ing the liquid willi a solution ol sodium in alcohol, wh.n the
.odium comiK.und i» precipitated. The piccipiiatc requires lo
be washed wi.h c.her, and is then dried over oil of vitriol ; the
NO. 13 iH, VOL. 51]

dry compound thus obtained affords numbers on analysis agree-
ing with the anhydrous formula above given In a former
mf.hod of prepar,tlian described by PiofMeyer, alcoholic
To^a was employed as precipitant, but .he sodium n'tromelhane
ob.ained invariably contained e.ther water or alcohol ; the use
of so.Uum ethvlalc affords it anhydrous. Kven the hjdratei
compound fir^t isolated proved .0 be explosive ; but upon
placfng a small quan.i.y of it upon a w.-chglass, ami warming
over a wa.crba.h, in a short time it '"^"'"^ ^".'''^'="'>. ',°"-
verted in.o the anhydro.s compound which mimed uitely
exploded with great violence. Wnen a small qt.antily of the
anhydrous compound prepared by use of sodium ethylate was
placed in a test tube, gently compressed, and .hen warmed, an
explosion of so violent a nature occurred that the test-tube was

I Prof z'linsky has recently had occ.ision to prepare consider-
able ouantities of -odium and potas-ium nilromelhane, and has
1 had the oppor.unity o( lesting and observing their explosive
power upon a larger scale. He appears to have adopted
essentially the same process for the preparation of sodium ni.ro-
methane as that described by Prof. Meyer, employing an
alcoholic solution of sodium eihylate as precipitating reagent.
Being desirous of obtaining the sodium compound peviectly
anhydrous, an attempt was made .0 achieve this object by
use of the «a.er b.aih, but lor the sike 0 precaution only
about a gram of .he .subs.ance was employed as a preliminary
?est of the efficacy of this method of dehydration. It was
fortunate .hat such was the case, lor «ithin hve minutes an ex-
plosion of so violent a nature occurred, that the w^'ch-glas--
ipon which the compound was supported was redviced to
powder, and the water bath cons.derably .njured. I""' "
demonstrate the explosive nature "f ','^'%'^°'"P°""i;^''!'°,"'
danger upon the lecture .able, Pro', /elinsky recommends the
fonowing^xperimem :-A th.ck clock-glass or l.etler a s^ul
metal plate, is sp.i.ikled with small drops of water, and a very
small i>iece of sodium nilromelhane dropped upon 1.. Alter a
f..w seconds, provided .he amount of water has not been
rxcessive, a deafening deiona.ion occurs, with production of
flame and projection of a thick cloud of smoke. The expert
ment may be varied by placing the substance upon the P^lectly
dry plaic, and invoking its explosion by means of a sm.arl blow
with a hard object. . „ \ a -u j

M Nef has previously (Ann. der Clumic, 280, 2n) described
seve.al of the metallic deriva.es of the nitroparaff.ns, and has
referred to the instabiU.y of the sodium compound, .and the
possibility of occasion.al explo-ions. Prof. Zel.nsUy "o-v siip-
plemenis this statement by lemarking that an explosion always
results from .he contact of the dry sod.um compound with a
minute quan.i.y of wa.er. One of his assistan.s upon one
occasion incautiously placed abou. five grams of sodium ni.ro-
methane in a glass vessel whose su.face happened to be mo st
with the result that a teirilic explosion instantly occurred, wh ch
shattered every piece of apparatus upon '^^ '"'•'•■■. »"f"^^=f
atmospheric wave pioduced occasioned ,he sudden ex.iuction of
lhewhdeoflheg.as flames in .he laboratory. The assistant
fortunately escaped more than .rilling injury, but » ^ec"n-i *u.h
occurrence might have a very dilleren. result. This incd.nl
will doub.less se.ve .0 emphasise the great precaution which is
necessary in handling these compounds.

The potassium compound, ClUKNO,, has been P'cP"ed in
a similar manner, and found to I.e even ..yue "";'••>''!;;''•;
1 ihe sodium cuipound. explo<l,ng at the ordinary "^"'P' *'""=,
' shortiv alter its isolation. It separates upon the addition of
hepoussium ethyl.ite in well defined crjslal-. .Jhe crystalline
form^. however, sJon disappears and upon rapidly t--n;^femng
10 a filler, an explosion invari.ibly occurs as soon as "'«."'"
pound becomes dra.ned Iree ol mos. of .he "-'her ..pior^
The in-tabili.y of the polnssium compound at the orciinary
tenrp'a.ure may also bc"readily demons, i.a.ed upon the lec.u^o
table It is. ol course, necessary to prepure it freshly on the
po., because of .he impossil.ili.y of preserving it for any length
of time. An ethereal -oluiion ol nilromelhane is mixed with a
Tolu-rn of po.as.siuin e.hyla.e in alcohol, .lie -P"n.a.an liqu d
rapidly decanted from the precipitate V'"'^^^'^'^- '^'^ }^\l^\^^^
as quickly as possible bc.ween filler paper, and left quietly
"stmg upon "•"= paP". After a lew minutes the substance
explodes wi.h a loud de.onaiion.

These expcrimen.s will serve .0 indicate the «"■«""="
slabili.y of .he alkali-metal derivatives of nilromethane. and
the violence of the explosions produced by their ^^^l^^"^;

January 31, 1895]

NATURE

329

RECENT WORK AT HARVARD COLLEGE
OBSERVATORY.

'PHE forty-ninth annual report of the [director of the Ila-varl
College Astronomical Observatory, by Prof. E. C.
Pickering, has come to hand. Omitting mitteri of administra-
tion and some of the details, the following summary ■^hows the
most important events of the year covered by the report.

Photometric Observations.

The reduction of the photometric measures of the southern
stars observed by Prof. S. I. Bailey in Peru, is now completed,
and the catalogue containing the resulting mignitudes is in
print. The observations of the first investigation undertaken
with this instrument since its return from Peru are nearly com-
pleted. About six thousand stars have each been observed on
at least three evenings. This catalogue includes all the stars of
the Harvard Photometry, eighty lists of comparison stars for
variables of long periods, and various stars the magnitudes of
which are desired by other astronomers. A study has been
made of the atmospheric absorption, especially for very low
stars, and its coefficient has been derived on each evening, both
for the southern and the northern stars. These values are now
applied as corrections to the individual observations, instead of
adopiing a mean value of the absorption. .\ new working list
has been prepared of the stars north of -40"* having -nagnitude^
7'5 or brighter, and which have not alrealy b;en observed with
the meridian photometer. This list contains about fourteen
thousand stars, of which about two thousand have been observed
during the last year.

Pr.jf. Pickering refers to Mr. S. C. Chandler's criticisms on
the photometric observations made with the meridian photo-
meter. [A^lron. A'ach. vol.cxxxiv. p. 355, and vol. cxxxvi. p. 85.)
It is maintained that the meridian photometer possesses the
same advantages in measuring the light of a star that the
meridian circle does in measuring its position. In both instru-
ments absolute values are determined directly, and they are
obtained very rapidly. Stars are identified in the same way
in both, rapidly and accurately, and in both the systematic
errors are small, even if the accidental errors are in some cases
larger than those resulting from other methods. S'.ars can be
observed with the meridian photometer under favourable cir
cumstances nearly at the rate of one a minute, and the average
deviation of the results thus obtained does not generally exceed
one-tenth of a magnitude.

.\stronomicai. Photograph v.

The number of photographs taken with the 8-inch Draper
telesco,ie is 1657. The number taken in Peru with the 8 inch
Bache telescope is 1708. All of the spectra photographed
with these instruments have been examined by Mrs. Fleming.
.\s a result seven variable stars, U Puppis, V Cancri, V L-^onis,
T Sagitlarii, R Delphini, K Vulpecula;, and R Phcinicis,
have been shown to have the hydro:;en lines bright in their
photographic spectra. Unsuccessful attempts have been made
to photograph the specira of many other variables of long
period when at maximum, and no image has been obtained.
This has been found to be due in many cases to large errors in
the ephemerides, and has tieen remedied by depending upon
the observations of Mr. VV. M. Reed, and making the time of
photographing each star depend u|)on its observed, instead of its
predicted, brightness. Eleven new variables have bf en discovered
in the year, from the presence of bright h)diogen lines in their
spectra, tiesides three the variability of which w?s discovered
from changes in their photographic images. The number of stars
of the fifth type has been increased by seven, making the total
number of these objects 62. Five nebii'a; have been discovered
from I heir spectra. The hydrogen line H j8 has been discovered to
be bright in the spectra of five stars, and twelve stars have been
shown to belong to the fourth type. The specira of .\. G. C.
18049 and 22640 are peculiar. Several photographs have been
obtained of the new star in the constellation Norma. At the
Lick Observatory it was shown from visual observations that
its spectrum, as in the case of the new star in Auriga, had
become that of a gaseous nebula. This has been confirmed
from photographs taken at .-Vrequipa, whiv;h also show that
this olijec is now gradually becoming fainter. The spectra of
4557 stars on thirty plates have been classified for iht new
Draper Catalogue. On one of these plates covering ihs region

NO. 13x8, VOL. 5 I

of the variable star tj Carinx, 1 161 spectra have been
measured.

The number of photographs taken with the i l-inch Draper
telescope is 912. The lines in the spectrum of i Ursae Majoris
are found to be double in 59 out of 340 images, and of i3 Aurigae
in 47 out of £5.

.\n investigation has been in progress for some time for the
detection of stars having large parallaxes or proper motions.
Phoographs are taken in the usual position with the dim to-
»ards the object glas--, and also with the pla'e reversed, the
photograph being taken through the glass. These are repeated
at intervals of six months at the times when the effect of
parallax on their right ascension would have its greatest value.
Plates thus obtained may then be superposed so that th-i fibus
shall be in contact, and the two images of each star made to
appear like a close diuble with components north and south.
SuitU changes in position miy be detected by changes in the
position angle, and the amount of the parallax or proper
motion may be measured with great accuracy. Several hundred
s'ars have thus been shown to have no parallax exceeding hilf
a second.

OiisERVATiiiN IX Peru.

The meteorological station on the summit of Misti, at a
height of 19,200 fee', was succes-fully conduced far several
months, one of the assistants, generally .Mr. Waterbury, visit-
ing it every ten days, and readjusting the self-recocling instru-
ments. Unfortunately, early in .September, the shelter con-
taining the instruments was found to have been broken into,
and a number of the instruments carried off. Apparently the
robbery was committed by two Indians, whose tricks were
followed to a considerable distance. The property stolen
would, of course, be of no u-e to the thieves, and its intrinsic
value would be a small part of the actual loss. The work at
this station was conducted with great labour ; a mule paih had
been built to the summit, and the entire expenditure had been
large. It will be a serious loss to science if it proves impossible
to maintain the station.

The number of photographs obtained by Prof. Bailey with
the l3-inch Boyden telescope is 561, including some remarkable
charts. Among them may be mentioned photographs of the
Nebula of Orion with an exposure of eight hours, of the cluster
u'Centauri with an exposure of six hours, and of tj Carin.r; with
exposures of six and fourteen hours respectively. In some of
these, notwithstanding the long exposure, the image shows no
deviation from the circular form. This is mainly due to sub-
stituting for a finder two eyepieces attached to the main tele-
scope. One of them serves to follow a guiding star in the
usual way ; the other, directed to another star, shows if the
plate needs to be rotated in its own plane. This appears to be
an important improvement in making the best photographic
charts of long exposure, especially of the polar regions. By
the ordinary methods it is impossible to entirely correct such
errors as those due to flexure and refraction, which do not
depend upon the direction of the axis of the earth.

Atteniion is again drawn to the importance of making
use of the admirable atmospheric conditions at Arequipa. .\
telescope of the largest size would not only have most lavourable
opportunities for work, but a field unexplored with such an
instrument in the southern sky. Much could be done with a
smaller instrument, as is shown by the work already accom-
plished with the 13-inch Boyden telescope. Out of a list of
thirty telescopes having aperture exceeding 14 inches or more,
but one is mounted south of latitude -i- 35% and this one is not
in use. A moderate expense only would be recjuired to carry
out this plan.

Work with the .New Telescope.
One of the most important events of the year was a careful
trial of the Bruce photographic telescope. Nearly a thousand
photographs have been obtained with it. The spectra of the
faint stars prove very satisfactory, and stars too faint to be photo-
graphed with the other instruments can thus be studied. Bright
hydrogen lines have been found in the spectra of S Orionis, 8
Bootis, W Virginis and S Librje, and the spectrum of V
Ophiuchi has been shown to be of the fourth type. The length
of these spectra is about a quarter of an inch, which is sufficient
to .show much detail in the spectra of fairly bright stars. To
study still fainter spectra a prism of crown glass and of smaller
angle has been ordered. T he absorjjtion of the photographic
rays is less for this material, and it is expected that much fainter

i'O

NA TURE

[January 3 1,

1S95

spec'.' ' ' " .graphed, since the dispersion will also be

less - n.H yd l>een filled for ihe Bnice telescope,

sinci. _ experienced in making charts in which the

imager shall tje circular. Experiments are in progress in this
direction, .and it is hoped that the method described above as
applied to the ij-inch Boyden telescope will prove equally suc-
cessful with this instrument.

A variety of exi>eriments have been made to deteniiine the
photogr.iphic magnitudes of the brighter stars on a uniform scale.
It is now expected that this can l>e done with the transit
photometer for stars brighter than the third m.agnitude, and that
the scale can be extended to stars from the third to the sixth
magnitude by a scries of photographs which are being taken with
a portrait lens having an aperture of 25 inches. The images
a'e thrown out of focus, and the inlensiiy of the circular discs
thus ohtaine<l can be accurately measured.

ELECTRIC DISCHARGE THROUGH GASES}

(^NE of the most important and interesting branches o*^
physical science is that which deals with the connection
between electrical and chemical effects..

The investigations on electrolysis made within these walls
by D.ivy and Faraday proved that the imporlant class of elec-
trical phenomena associated with the passage of electricity
through liquids, are connected in the closest way with chemical
action. They proved that no electricity will pass through most
liquids unless chemical action occurs, and that for each unit of
electricity which passes through the liquid there is a definite
amount of chemical decomposition.

This case, though it is one where the laws are most accu-
rately known, is but one among many electrical phenomena
which are inseparable from chemical action.

So many instances of this kind have been discovered, that
we may perhaps venture to hope that we are not (ar from the
time when it will be universally recognised that many of the
most fundamental questions in chemistry and electricity are but
different aspects of one and the same phenomenon.

.\nyihing which throws light on the connection between
electricity and matter, interesting as it is on its own account,
acquires a'Iditional interest when regarded as elucidating the
connection between chemical and electrical effects, and no phe-
nomena seem more suitable for this purpose than those which
are the subject of the discourse this evening — the discharge of
electricity through gases. For in gases we have matter in the
state in which its properties have been most carefully studied,
while the investigation of the electrical effects is facilitated by
the visibility of the discharge, affording us ocular, and not
merely circumstantial, evidence o( what is taking place.

The points to which I wish to refer particularly this evening
are, firstly, some phenomena connected with the passage of
electricity from the gas to the electrode, or fr.>m the electrode
to the gas ; and secondly, some of the properties of the dis-
charge when its course lies entirely in the gas.

By taking a long discharge tube, say, one fifty feet long, and
observing the luminous discharge through a rotating mirror, we
can trace the course of the luminosity due to a single discharge,
»ay, one due to once breaking the primary circuit of an induc-
tion c mI ; if we do so, we find that the luminosity follows the
direct iofi of the pisitive current through the tube. That is, the
luminosity begins at the positive electrode, it then rushes down
the tutie with enormous velocity, but when it gets to the nega-
tive electrode, it receives a check ; it docs not disappear at once
in thAt electrode like a rabbit going down a hole, but lingers
around the electrode some time belore entering it. In conse-
quence of this delay in the positive discharge in getting out of
the ga-. there it an accumulation of positive electricity in the
neighi.-jurh..od of the negative electrode until the potential fall
at this electrode increases to about 200 or 300 volts.

The potiiive electricity which accompanies the discharge thus
find* considerable difficulty in getting from the gas to the metal,
(hough, as I hope to show you later on, a? long as it keeps in
the gas, it meets with what we may, in consideration of the
views sometimes enunciated on this subject, call a ridiculously
small amount of resistance, its real difficulty is to get out of the

gas.

Though this effect has long been known, it is so important
ire delivered :il ihe Roynl Inililulion by Prof. J. J. Thomson,
NO. 1318. VOL. 51]

that I will venture to show one or two experiments which
illustrate it. The arrangement of the first experiment is shown
in Fig. I. The apparatus consists of a main discharge tube,
across which is fastened a diaphr.agni made of excessively thin
platinum leaf; there is a side passage from the tube, leading
from one side of the diaphragm to the other, this is connected
to a barometer tube, and by raising the cistern containing the

^g

mercury I can stop up the pass.ige by a pellet of mercury. We
will first observe the ilischarge when the side passage is open ;
you see that the discharge, instead of passini; acoss the thin
piece of platinum leal, takes the very much longer route round
the side tube, so as to avoid crossing the metal. We will now
raise the mercury cistern, and close the side lu'ie by a pellet o(
mercury ; the discharge now has no alternative but to cross the

metal at some part of its course, and you see that the main
portion of the discharge goes back into the main tube.

In the seond experiment the metal diaphrag'U is replaced by
a very thin plate of mica ; when the side passage is opened the
discharge goes lound, but when this is closed by a pellet of
mercury Ihe discharge prefers to go across the mica than through
the mercury.

January 31, 1895]

NATURE

331

A second experiment which shows the same thing is the
following. Two long electrodes are fused inio a bulb, so that
the tip of an electrode is a considerable distance from the place
where it passes through the glass. We will now send an alter-
nating discharge through the tube, and you will see, I think,
that the discharge, instead of going straight across the short
distance between the ends of the electrodes, goes from the tip
of one electrode to the place where the other passes through
the glass, thus staying as long as possible in the gas before
passing into the metal. The appearance of the discharge
shows that the positive electroHe is at the end of the wire, the
negative at the junction of the wire with the glass.

.\nother interesting example of the difficulty the discharge
experiences in passing from gas to metal is the discovery made
by Profs. Liveing and Dewar, that when the discharge passes
through a gas containing a large quantity of metallic dust, the
light from the discharge, when examined in the spectroscope,
does not show any of the lines of the metal.

The difficulty which the positive electricity finds in passing
from the gas to the electrode depends a great deal upon the
nature of the gas, as well as upon that of the electrode ; it is
influenced by the position of the gas and the electrode relatively
to one another in the electrochemical series.

I have lately made a series of experiments on this point in
the following way. An alternating discharge from a high
tension transformer was made to pass between two electrodes
fused into a bu|l>, which could be filled with the gases under
examination, .\nother electrode connected to an electrometer,
passed into the bulb, and was arranged so that it could be
moved about from one part of it to the other. When the
electrodes were metal and the bulb was filled with the electro-
negative gas oxygen, the electrode received a positive charge in
whatever part of the bulb it was situated ; if now the bulb was
filled with hydrogen at atmospheric pressure, then in the regions
remote from the arc the electrode received a positive charge, but
in the immediate neighbourhood of the arc itself it received a
negative charge. When the pressure was reduced the region
in which the charge was negative contracted, and finally at
pressures about one-third of an atmosphere, seemed to disappear,
and the electrode got a slight positive charge in whatever
position it was placed. If now, instead of using metallic
electrodes we use well-oxidised copper ones, and repeat the
experiment in hydrogen, working at a pressure when there was
only positive electricity, when the electrodes were bright and
polished, we find that with the oxidised electrodes every particle
of positive electricity is taken out of the tube, and a negative
charge is left. This negative charge remains until the copper
oxide is completely reduced; when this occurs the negative
charge disappears, and is replaced by positive. Thus, under
the same conditions as to the nature of tbe gas and the pressure,
the bright copper electrodes leave a positive charge in the gas,
while the oxidised ones leave a negative charge.

The most probable explanation of these results seems to me
to be the view that the communication of electricity from gas to
the electrode, or from the electrode to gas, is facilitated by the
temporary formation of something of the nature of a chemical
compound between the gas and the metal. In all such com-
pounds the metal is the electro-positive element, and has the
positive charge, the gas being the electro-negative and carrying
the negative charge. Now consider the case when the negative
charge is on the gas, and the positive charge on the metal ; then
the gas and metal have got the charges proper to them in any
compound they may form, and are thus in a fit state to combine, or
according to this view, allow the negative electricity to pass from
the gas to the copper. Hut, now, suppose the gas w as positively
electrified, the g.is and the metal have now opposite charges to
those proper to them in a compound, and before the union of
gas and metal in this slate could result in anything but a most
unstable compound, an additional process must be gone through
— i.e. the charges on the gas and metal must be interchanged.
Thus the conditions for the combination of the gas and metal
arc more complex when the gas is positively electrified than
when it is negatively electrified, and thus, on the view that the
communication of electricity between the gas and the metal
involves a sort of chemical combination, we see '.hat the negative
electricity will escape more easily from the gas to the metal
than the positive. Now consider the case when the gas was
hydrogen, the electrodes oxidised copper ; the hydrogen
combines now not with the metal, but with the oxygen, forming
water, in which hydrogen is the electro-positive element ; thus,

NO. I 3 18, VOL 5 l]

in this case, it is the positively charged hydrogen which is in
the state best fitted for pairing. The consequence is, the
positive charge would be most readily removed from the gas
and the negative left — exactly the opposite to that which
occurred when the electrodes were bright. This reversal, as 1
stated before, is verified by experiment.

I have hitherto only spoken of the phenomena which accom-
pany the passage of electricity from the electrode to the gas, or
from the gas to the electrode.

I shall now pass on to consider the properties of the discharge
when it is entirely confined to the gas.

We may produce a discharge which, during the whole of its
course, shall be confined to the gas in the way represented in
the diagram.

The two poles of a Wimshurst machine are connected to the
insides of two jars A and B, while the outsides of these jars are
connected together by a metal wire wound so as to form a coil.
The electricity from the Wimshurst machine charges up the
jars, the difTerence of potential between the poles increases
until a spark passes. The passage of the spark puts the insides
of the two jars in connection, and the jars are discharged. The
discharge of the jar, as was proved from the theory ol electro-
magnet action by Lord Kelvin more than forty years ago, and
shortly afterwards confirmed by the experiments of Feddersen,
is an oscillatory one, producing currents surging backwards and
forwards through the wires with extraordinary rapidity. The

subject of these oscillatory currents is one which is tinged with
melancholy. In the beginning of 1894 we lost Hertz, whose
splendid work on these electrical oscillations is known to you
all. The Managers of this Institution have marked their sense
of the importance of this work by devoting a special lecture to
this work alone, and they have entrusted that lecture to a most
distinguished worker in the same field as Hertz. It would
therefore be presumptuous on my part to refer in any detail to
Hertz's work ; but no physicist, and least of all one who is a
member of Maxwell's University, could pass over in silence the
death of Hertz.

When Hertz began his magnificent experiments on electric
oscillations, there were many theories of electrical action.
When he had finished them there was only one, Clerk
Maxwell's.

Hertz's work was done with very much quicker vibrations
than those produced by the apparatus no* on the screen ; this,
however, gives rise to currents through the coil changing
their direction some million times a second. If we place in
the coil an exhausted bulb, the bull) in reality will be the
secondary of an induction coil, and will be exposed to electro-
motive forces tending to produce circular currents parallel to
the plane of the coil.

I will now place a bulb inside this coil, and you see that a
circular ring discharge passes through il, and this discharge
passes entirely in the gas.

The gas in the bulb now in the coil is the vapour of silicon
tetrachloride ; it happens to be the bulb which gives a brighter
ring than any others 1 possess.

332

NA TURE

[January 31. 1895

If ihis rinR discharge passes through air at different pressures,
the colour of the discharge chaoges very considerably. The
firet bulb I put in was at fairly high pressjre, about ,',7 of a
mill i met re or s'». I will now put in another at a lower pressure,
and then one at a still lower pressure. Mr. .Vewall, who has
been working at the spectra of these ilischirJe*, fin Is that at
the pressure in ihe first bulb the spectrum is due to nitrogen ;
at the second stage it is due to mercury vapour ; the bulb was
pumped by a mercury pump, so that there is in the bulb a
certain quanii y of mercury vapour.

The apple-gteen colour in the more highly exhausted bulb is
due 111 some compound of sulphur, which has got into the bulb
from the sulphuric acid used to dry the gas. .Mr. Newall finds
that if the ordinary discharge from a coil between electrodes is
taken in such a bulb, there is no trace of this sulphur spectrum.
He has also found that when the bulb is at a pressure inier-
mediate between what I may call the mercury and the sulphur
stage, when the mercury and sulphur lines are both visilile,
these sets of lines come from dilVerent layers, the sulphur lines
coming from a layer nearer the surface than the other.

If we take the discharge through a bulli containing osygen,
jrou will see that the ring discharge is succeeded by a bright
glow : at first the colour is somewhat opaque, but gradually gets
more transparent and changes colour. This gives a continuous
spectrum crossed by a few bright lines. If we take the discharge
through cyancgen, you see that the glow is even more persistent
than the oxygen, though it is not so bright ; all the gases which

Fig *.

show this glow belong to the class of substances which poly,
merise — that is, whose molecules can combine with each other.
I imagine that what lakes place in bulbs filled with these sub-
stances is that the discharge produces a polymeric modification,
and that this gradually returns to its original stale, and » hilc
doing so gives out a pinsphorescent ligh'. It is in accordance
with this that al a high temperature where ozone canno: exist
a discharge through an oxygen bulb dcics not show any glow.

I said at the beginning of this discourse that gases were exceed-
ingly good conductors of electricily. I will now endeavour to
show an cxperimcnl which proves that statement. The apparatus
which I shall use for this purpose is a slight modification of
the one I have used for prorliicing the ring discharge ; the only
difference is that in ihe wire connecting the two c latiiigs of the
jars there are two loops instead of one. In one of these loops
an exhausted bulb is placed to serve as a kind of galvanometer ;
the brightness of the discharge is an indicalinn of the strength
of the current flowing round the c >il. Il I plac; a seco n'
conductor in Ihe other loop, cuTent- will be started in i;, imd

f>»rt of the en;rgy of the dii,.hirge will be absorbed j this will
cave less energy available for the bulb in the first, so that the
discharge in this bulb will be dimmer. The effect produced on
Ihe di<chiri;cwill depend upon the conductivity of the substance
placed in the second loop.

The effect ii no*, directly proportional to the con lucliviiy ; in
fad, a perfect conductor would not produce any diminution,

NO. 13 ifS, VOL. 51]

nor would an absolute non-conductor ; for a given period, and
with apparatus of given dimensions, there i.s a certain c indiic-
tivity which gives a maximum effect : ihis foil 'ws easily from
ihe theory ol induction of currents, but at this laie period in
ihe evening I will take a shorter course and prove it by an
experiment.

I put a piece rf br.ass in this loop, and you see it produces but
a small efTtci U|ion the Iprightness o( the discharge. Instead of
brass I now insert a plumbago crucib'e, which, ihough a con-
ductor, is not nearly s j good a one as the brass, and you sec the
discharge in the indicating bulb is completely stupped.

I will now place in the second loop an exliaiisted bulb ; you
see it pr.iduces a decided diminution in the intensiiy of the dis-
chatge in the galvanometer bulb. I now replace the bulb by
another of the same size containing dilute sulphuric acid ; yon
see il does not produce nearly so large an eflccl as the exhausted
bulb : this might be due, as we have seen, to the sulphuric acid
being either too good or too b.ad a conductor. I can >how that
it is the latter by putting a bulb in filled wuh a stronger solu-
tion, which has a higher conductivity than the weak solution ;
if the smallness of the ertect produced by the weak acid were
due toils being a better conductor than the g.as, then increasing
the conductivity would still further diminish the efl'ect of the
acid ; yiu see, on the contrary, that the strong acid produces a
distinctly greater effect than Ihe weak, hence the rarefied gas in
the bulb is a better conductor even than the strong electrolyte.
Let us con<^ider for a moment the molecular c ■r.ducnviiies of
the two substances, the raicfied gas and the electrolyte. The

Fig 5,

pressure of the gas is about ,,',,. of a millimetre, «hilc in the
electrolyte there are sufTicient molecules of the acid to produce,
if they were in Ihe gaseous state, a pressure of more than 100
atmospheres ; thus the conductivity of the gas eslimaled per
molecule is about 10 million times that of the acid, this is greater
than the molecular conductivity of even Ihe best conducting
mel.ils.

If the pressure of the gas is diminished below a certain point,
the conductivity begins to diminish. I have here an experi-
ment which I hope will show this. The apparatus (Fig. 5) con-
sists of two bulbs, one outside the other ; the inner bulb con-
tains air at a low pressure, while the space between the two
bulbs is a very high vacuum conlaining practically nothing but
a litlle mercury and iis vapour. The amount of mercury vapour
in this space is, at the leniperauire of the room, exceedingly
small, but as the apparatus is heated the vaoour pressure in-
creases, and we are thus able to produce a fairly wide range of
pressu.e in :hc space lelween Ihe bulb-. The outer sphere is
■ui'rourdcd by the coil connecling the outer coalings of the two
I.eyden jars. When ihc space between the bulbs is a conductor,
the alternating currents circulating in the coil will induce
in Ihis conduciur curicnis whose inductive effect is opposite
to Ihal of the currents in the coil ; and in ihis case Ihis layer
will screen off from the inner bulb the electromotive force due
lo the alternating currents in Ihe coil. If, on the other hand,
the space between Ihe bulbs is a non conductor, Ihe inner bulb
will be exposed to the full ellecl of these forces. We now try

January 31, 1895]

NA TUKE

333

the experiment : you observe that when the mercury is cold,
and consequently the pressure in the space between the bulbs
very low, a bright discharge passes through the inner bulb,
while the space between the bulbs remains quite dark ; when
we heat the mercury so as to increase the pressure of its vapour,
a bright discharge passes through the outer layer, while the inner j
bulb is quite dark ; the outer layer is now a conduclor, and by its !
action screens off from the inner bulb the induction of the coil.
The last experiment I have to show is one on the effect pro-
duced by a magnetic field on the discharge. When the dis- ,
charge has to flow across the lines of magnetic force, the pres-
sure of the magnetic iield retards the discharge ; when, however.

the discharge flows along the lines of magnetic force, the dis-
charge is helped by the magnetic field. This is shown in the
following experiment. A is a bulb ; B a square tube, one side
of which is placed between the poles of an electromagnet ; the
coil C, which connects the outside coatings of the jars, can be
adjusted so that when the magnet is "off," the discharge passes
through the bulb but not round the square tube ; when, however,
the magnet is "on," the discharge passes in the square tube but
not in the bulb In the square tube the discharge passes along
the lines of magnetic .' orce and is helped ; in the bulb it passes
across them and iv retarded.

UNIVERSITY AND EDUCATIONAL
INTELLIGENCE.

Oxford. — In a Convocation held on Tuesday, January 29,
the degree of Doctor of Medicine, by decree of the House,
was conferred on J. S. Burdon Sanderson, F. R. S., Regius Pro
fessor of Medicine. Prof. Sanderson was at the same lime em-
powered to discharge the duties of the Waynflete Professor of
Physiology, and to dispose of the income of the department
during the vacancy in the Waynflete Professorship.

The amendments to the proposed form of statute on degrees
for research will be submitted to Congregation on Tuoday,
February 12. There are no less than sixty-three amendments,
most of which are consequential. The chief amendments pro-
I pose that the degree of Bachelor of Arts shall be substituted
lor the proposed degrees of Bachelor of Letters and Bachelor
if Science ; that the delegacy for the supervision of candidates
ihall be chosen from among a limited number of University
officials, and that there shall be no such delegacy, but that the
supervision shall be entrusted to the Boards of Studies.

The Sibthorpian Professor of Rural Economy will deliver an
inaugural lecture on Monday, February 4, at 5 30 p.m., on "The
I'resent Relations of .Agricultural Art and Natural Science."

Mr. A. B. Trevor Battye will give a lecture before the Ash-
inolean Society on Monday, February 4, at 8. 30 p.m., on his
■xperiences in Kolfjuev Island.

The Vice-Chancellor has received for the University a bequest
Irom the late Miss Susan Kidd of a portrait of her father, Dr.
Ijohn Kidd, of Christ Church, formerly Regius Professor of
jMedicine.

CAMiikiiiGE. — The Special Board for Biology and Geology
lopose that in fuLuie the Walsingham Medal, given by the Lord

High Steward annually for biological research, shall be open
to graduates of the Univeisity up to the standing of Master of
Arts. Of the three Medals offered, two have been awarded — one
for a zoological and the other for a botanical essay. It is also
proposed that the Medal shall not be awarded twice to the same
person.

The funeral of the late Prof. Cayley will take place on Friday,
February I, in Trinity College Chapel, and the Mill Road
Cemetery. Members of the University desiring to be present,
are requested to assemble in the College Hall at 1. 45 p.m.

The Sedgwick Memorial Syndicate have been empowered to
reconsider the plans, or prepare new ones, for the Geological
Museum. The estimates for Mr. Jackson's plan exceeded the
means at the disposal of the University.

Dr. L. E. Shore, St. John's College, has been appointed an
additional member of the Medical Board. Dr. A. Ransome,
F.R.S.,Dr. J. L. Notter, Dr. T. Stevenson, F.R.S,, and Dr. R.
Thorne Thome, C.15., f. R S., have been appointed Examiners
in State .Medicine for the current year.

At the Matriculation on January 28, seventeen new students
were entered. This brings the total for the present academical
> ear up to 894.

The Executive Committee of the City and Guilds of London
Institute have awarded the first Salters' Company Research
Fellowship for the encouragement of higher research in
chemistry in its relation 10 manufactures, to Dr. Martin O.
Foster. Dr. M. O. Foster is an old student of the City and
Guilds Technical College, Finsbury, and Doctor of Philosophy
of the University of Wurzburg. For several months he has been
engaged in investigating some new derivatives of camphor in
the Research Laboratory of the City and Guilds Central
Technical College and by the aid of the Salters' Company's
Research Fellowship, he proposes to pursue this line of work.

The Organised Science Schools of the Department of .Science
and Art are schools in which the instruction is carried on
methodically according to one or other of the courses laid down
by the Department, or which has been specially submitted to
and approved by it. It can easily be understood that such
schools represent a very important stage in the system of scien*
tific education which Mr. Acland is doing so much to improve.
A number of new regulations, relating to these schools, have just
been issued, to come into force after the examinations next
May. The most important feature of the new scheme is the
introduction of payment on inspection instead of payment on re-
sults, for by far the larger part of the instruction given in organ-
ised science schools. This modification, which applies to 120
science schools in the United Kingdom, has only become pos-
sible since the app iintment of a staff of Science and Art in-
spectors. Another noteworthy feature is that reasonable lati-
tude will be allowed to the teacher as to the nature of the course
he may pursue provided the instruction is sound, satisfactory in
amount, and combined with proper practical work. Even more
satisfactory are the instructions that the practical chemistry for
the first year's course should include the setting up of apparatus —
weighing and other chemical manipulations, the preparation of
gases, ihe estimation of volume, and so on. .Xnalysis will, in
future, occupy a secondary position in introductory courses. The
mechanical test-tubing, which has hitherto formed the greater
part of practical chemistry in Departmental schools, will thus
give place to practical work of real educational value. We also
observe that provision is made for a certain amount of literary
instruction being given whilst the student is pursuing his science
curriculum ; that a choice of advanced courses is given ; and
that an alternative programme suitable for women is formulated,
and instruction in subjects specially adapted to them is de-
manded ; that practical instruction must be given in the subjects
of science simultaneously with the theoretical instruction.
Clearly, the new rules will greatly assist the development and.
better organisation of scientific education.

NO. I318, VOL. 51]

SCIENTIFIC SERIALS.

American journal of Science, January. — Late glacial or
Champlam subsidence and reelevation of the St. Lawrence River
basin, by Warien Upham. From the Champlain submergence
the Atlantic coast of North America was raised somewhat
hii;her than now ; and its latest movement from New Jersey to
Greenland has been a moderate depression. As in Scandinavia,

NA TURE

[Januarv 31, 1895

the restoration of isos'atic equilibrium is attended by minor
oscillaMons, the conditions requisite for repose having been
OTerpassed by the early rei.levation of outer portions of each o(
these great glaciated areas. The close of the Ice Age was not
long ago, geologically speaking, for equilibrium of the disturbed
areas h.^s not yet been restored. — .\n automatic mercury vacuum
pump, by M. I. Pupin. This pump is a combination of a suction
pairp capable of raising mercury to practically any height, and
an ordinary Sprengel pump, the two being connected by a
siphon barometer Mercury is pumped into the Sprengel
reservoir by the suction pump. The reservoir of the latter is
provided with two vertical tubes dipping into two mercury
vessels. The end of ore of these is higher than that of the
other, so that when the mercury has fallen to the level of ihe
end, no more mercury enters the tube, and the column already
in it is bodily drawn up into the siphon barometer. — Graphical
tfaermodyoimics, by Rene dc Saussure. The author recom-
mends the adoption of new coordinates inste.-id of P and V.
Instead of these, he advocates the variables ip and s, defined by
the equations ^ = t'»"-' and s = xa-, where i is the period and
a the amplitude of the vibratory motion constituting heat.
Then the value of each variable depending upon the phenomenon
can be obtained graphically. — Solutions of salts in organic
liquids, by C. E. Lincbarger. 1 he law enunciated by Schroeder
and Le Chatelier, that the solubilities at equal intervals from
the temperature of fusion for different solid bodies and in
difTerent solvents are the same, although approximately true
for the cases investigated by them, is not applicable to the case
of inorganic salts in normal organic solvents.

Wifiirmaiin's Aiirialen der Physik und Chemie, No. 13,
1894. — A new spectrum photometer, by Arthur Kimig.
Between the telescope and the collimator, which is provided
with two parallel slits, are introduced, besides the refracting
flint-glass prism, a twin prism and a Rochon polarising prism.
One of the slits is provided with a total-reflection prism, in
order to admit Ihe standard light from the side. The iield of
vie* shows two semicircles, one for each of the sources of
light, and their relative intensities can be adjusted and
measured by a Nicoll prism near Ihe eye. The observer notes
the angle through which the Nicoll prism must be
rotated in order to give equal intensities to the two halves of
the field.— Spectra of various sources of light, by Else
Kotigen. By means of K'^nig's spectrum photometer, various
petroleum and gas lamps were spectroscopieally studied. — On
the process of light emission, by G. Jaumann. The author
shows that the emissive vibrations of a luminous body exhibit
a damping which maybe measured — Capillary electrometers
and drop electrodes, by G. Meyer. The surface tension of
mercury and some, but not all, amalgams is reduced by the
addition of a solution of a salt of mercury, or of a salt of the
metal contained in the amalgam. The reduction of .surface
tension which takes place during anodic polarisation is due to
the formation of such mercuric or metallic salts. — Thermo-
electricity of chemically pure metals, by K. Noll. This paper
gives an account of a careful redetermination of the thermo-
electric forces of pure Cd, Sn, Ag, Au, Cu, Zn, Al, Pt, Mg, Fe,
Ni, Hg, and German silver. — Influence of magnetisation and
lemperaiure upon the eltctric conductivity of bismuth, by J. B.
Henderson. The author shows that, before bismuth spirals
can be employed to measure magnetic fields by their change of
resi<tance, it will be necessary to lind a ready me.ins of testing
their temperature, as the resistance is profoundly affected by
change in the latter. — High temperature thermometers of Jena
glass .N'o. 59'!' , by .\lfons .Mahlke. These thermometers have
to be filled partly with liquid carbonic acid, after which they
maybe employed for temperatures up to 550, the carbonic
acid keeping the mercury from boiling. The author dcfcribes
how he found the expansion of the glass and Ihe mercury (or
such high temperatures, and calibrated one of the thermo.
meters with reference to the air thermometer.

Bulliiin de la Sini/ti dt> Natural! ltd de Afoscoit, 1894, No.
I. — Contributions to the Moss flora of Russia, by iJr. Ernst
/ickcndratb, being an enumeration of 202 species collected by
Ihe author in European Russia proper (in German) — The
formation of the primary blastoderms and the origin of Ihe
chord and the mesoderm in the Vertebrates, by H I^wolT (in
German, with sis plale«). A work which alieady has been
partially published in Hiolo^iichei CrnlralHatt for 1892 ; it is
based on the study of the embryology of the Amphioxiis,

NO. 13 18, Vr.L. 51 ]

the Pttromyzon, the Axolotl, the Pristinrus and Torpedo,
several fishes and the I.aceria, an 1 the author comes to the
conclusion that the whole of the process is quite difi'erent from
what is usually described as gastrulation. The paper is to be
continued. — .A. general expression of the Thermodynamic
Potential, by N. OumotT. — -Meteorological observations at
the Petrovak .Agricultural .\cademy for the year 1893.

SOCIETIES AND ACADEMIES.

London.

Royal Society, January 17. — "The Latent Heat of
F.v.iporaiion of Water." By E. H. Griffiths, M..\., Sidney
Sussex Collet;e, Cambridge.

.\ calorimeter was suspended within a chamber the walls of
which were kept at a constant temperature in the manner
described in a previous paper.' The calorimeter was filled
with a singulaily limpid oil, which was stirred by paddles
revolving about 320 times per minute, and immersed in the
oil was a silver flask, which contained the water to be evaporated.
The ends of a platinum-silver coil, within the calorimeter, were
maintained at a known constant poiential difierence, and the
rate of evaporation so controlled as to exactly balance the heat
supplied by the electric current. The advantages of this
method are that the results are not appreciably afTected by
(1) eirors in thermometry ; (2) changes in the specific heat of
water ; (3) errors in the determination of the water equivalent ;
(4) loss or gain by convection, &c. DitTcreniial platinum-
thermometers were used, in order to ascertain the equality of
Ihe calorimeter temperature and th.Tt of the surrounding walls,
thus differences of 00004° C. eould be accurately measured,
and smaller differences detected. -

A series ol experiments in which the saturated vapour was
removed from the flask by a stream of dry gas, gave the following
results.

Temp. (Nitrogeo L (in terms of a therm.tl

Scale). unit at i;,^).

24"-96 5819

39 '99 5724

49"'82 5'>6 5

The method of experiment was then altered ; rapid evapora-
tion was caused by removal of pressure, and the mass of water
evaporated determined in a different manner.

A considerable number of experiments gave the following
results.

Temp. (N. Scale). Extreme values of L. Mean I,.

30^00 ... 578 58 - 5/8 90 ... 578 70
4o'''i5 ... 572-12 - S73'oi ... 572-60

The conditions as to rate of evaporation, &c., were varied
greatly during the experiments.

The results are expressed by the following formula :

L = 59673 - 0-60109

This formula would give

L = 596-73 when 9 = o
and L = 53663 ,, « = 100°.

.\nd these values are aim 1st identical with those obtained by
Uielerici at o' (596-73) and Regn.iult at 100 (536 60). A study
of the results leads the author to the conclusion th.-it Ihe
" thermal unit at 15° " must be almost identical with the " mean
thermal unit between 0° and 100." It has been shown by
Rowland, by Itartoli and Stracciati, and by the author, that at
low temperatures the specific heat of water decreases as the
temperature rises, and it is proha'<Ie that it arrives at a minimum
between 30 and 40°, afterwards increasing with rise of tem-
perature. There is, therefore, nothing impossible in the above
supposition.

An investigation into the density of aqueous vapour
(assuming the author's values of I. and J) indicates that at
low pressure- the density of the saluratc<l vapour is that of a
perfect gas, and that at higher pressures (above 140 m.m.) it
attains a density about I -02 times as great as the "theoretical
dt nsily."

January 24. — ^" Malhemalical Contributions to the Theory of
Evolution. II. .Skew Variation in Homogeneous Material. " By
Prof. Karl Pearson, University College, London. (Seep. 3'9)'

I ''The Mccfianical Kquivalent,' Phil. Trans. 1893 A, pp. 361-504.
'-■ Sec Phit. Mat;. January 1895.

1

January 31, 1895]

NA TURE

i35

Royal Microscopical Society, January l6. — Annual
meeting. — A. D. Michael, President, in the chair. — After the
report of the Council for the past year and the treasurer's
statement of accounts had been read and adopted, the
President announced that the following were elected as officers
and Council for the ensuing year : — President, A. D. Michael;
vice presidents, Prof. L. ,S. Beale, F. R S., Dr. K. G. Hebb,
!•.. M, Nelson, T. H. Powell ; treasurer, W. T. Suffolk ;
secretaries. Prof. F. Jefit'rey liell, Dr. W. H. Dallinger,
F. R S. ; ordinary members of Council, T. D. Aldous, C,
Beck, A. W. Bennett, Dr. R. B'-aithwaite, Rev. 1£. Carr.
Frank Crisp, K. Dadswell, G. C. Karop, C. F. Rousselet, Dr.
H. C. Sorby, F.R.S., J. J. Vezey, and T. Charters White. The
President then delivered the addres.s, the subject being, "The
History of the Royal Microscopical Society." The President
said that if any of his hearers would leave that West-end
abode of science, and journey eastward to Tower Hill, and
thence by Sparrow Corner along Royal Mint Street, he would
find himself in Cable Street, St. George's-in-the East, not a
very quiet or a very clean locality ; turning down Shorter Street
he would emerge opposite a space of green, where once stood
the Danish Church, with its Royal closet reserved for the use
of the King of Denmark when visiting this country ; the space
is surrounded by houses which have seen better days, and
amongst them, between a pickle-factory and a brewery, stands
a rather dilapidated erection which is 50 Wellclose Square ;
where, in 1839, lived I'.dwin J. Quekett, Professor of Botany at
the London Hospital ; and there, on .September 3 of that year,
seventeen gentlemen assembled "to take into consideration the
propriety of forming a society for the promotion of micro-
scopical investigation and for the introduction and improvement
of the microscope as a scientific instrument." Among the
seventeen were N. B. Ward, the inventor of the Wardian-case,
which is not only an ornament to town houses, but was the
means of introducing the tea-plant into Assam and the
chinchonas into India, and who became treasurer of the
society : Bowerbank l.i>ter, who has been called the creator of
the modern microscope ; Dr. Farre, Dr. George Jackson, the
Rev. J. B. Reade, and the enterprising and scientific nursery-
man George Loddiges. Most of these subsequently became
presidents of the Society. .-^ public meeting was held on
December 20, 1839, at the rooms of the Horticultural Society,
then at 21 Regent-street, when the " Microscopical Society of
London " was formally started. Prof. Richard Owen (not Sir
Richard at that time) took the chair and became the first
president, and shortly after the famous John Quekett became
secretary, an office which he held almost to his death. At this
moment Schleiden in Germany was commenting upon the
paucity of British microscopical research, and attributing it to
the want of efficient instruments, not knowing that a society was
then forming which was to raise British microscopes to probably
the first position in the world. The President then traced the
history of the Society through the presidencies of Dr. Lindley
the botanist. Prof. Thomas Bell the zoologist, Dr. Bowerbank,
Or. George Busk, Dr. Carpenter, Dr. Lankester, Prof. \V.
Kitchen Parker (all deceased), and of others equally famous who
are still living ; and showed how, under its influence and by its
assistance, the vast improvements in the microscope, and the
enormous extension of its use had gradually arisen ; he also
described its connection with the origin of the Quarterly
fournal of JMicroscopical Scit-iicc, the Monthly Microscopical
journal, and other publications, besides its own present widely
circulated journal with its exhaustive summary of microscopical
and biological work. He related how on John Quekett's death
certain members of the Society subscribed to purchase for the
Society's collection a curious microscope which Quekett
possessed, and which had been made by the celebrated Benjamin
Martin about 1770, probably for George III., and how they
extended their subscription so as tn provide a medal to be
called "the Quekett medal" to be given from time to time
to eminent microscopists ; and how, difliculiies having arisen,
it happened that the only Quekett medal ever awarded
was given to Sir John Lubbock. Finally, the President
considered the future of the microscope and the prospects
of further improvements. He said that many people were
of opinion that the instrument is now perfect, and that
consequently the most important ration ifi'/rc of the Society
was over ; he by no means agreed in that view, he believed
that there was as much scope lor progress in the future as there
had been in the past ; it was not by any means the first time

that this idea haii been put forward. In 1829 Dr. tioring, then
a great authority on the subject, wrote in one of his published
works : " Microscopes are now placed completely on a level with
telescopes, and like them must remain stationary in their
construction." In 1830, less than a year after, appeared
Lister's epoch-making paper, "On the improvement of
achromatic compound microscopes," and we have been im-
proving ever since. — Mr. II. V. Teblis proposed a vote of
thanks to the President for his address ; this, having been
seconded by Prof. Bell, was carried.

Edinburgh.

Royal Society, December 17, 1894. — The Hon. Lord
M'Laren, Vice-President, in the chair. — Mr. Patrick Murray
read an obituary notice of the late Mr. Donald Beith. — In a
paper on germination in ponds and rivers, Mr. H. B. Guppy
described observations on the germination of semi-aquatic and
arjuatic plants, and discussed the effects of temperature and light
— .\ paper on the Hall effect and some related actions in bis-
muth, by Mr. J. C. Beattie, was read. Mr. Beattie finds, with
high fields, a reversal of the Hall effect in certain specimens of
bismuth. — Mr. George Romanes communicated a paper on at-
traction treated by graphic processes, with deductions.

January 7. — The Rev. Prof. Flint, Vice-President, in the
chair. — Dr. W. Peddie read a paper on a case of yellow-blue
blindness, and its bearings on the theories of dichromasy. The
historical aspect of the Young- Helmholtz theory is as follows :
(i) Young gave his theory of colour-blindness by lapse of one
sensation, stating that this seemed to him to be simpler than
any other assumption. But, as with his theory of colour-vision,
he meant this theory to be given up if it were subsequently
found to be inconsistent with experiment. (2) Helmholtz added
his ideas regarding the nature of the mechanism, adopting
implicitly Young's reservations, and stating explicitly that his
ideas, if false, did not afTect the basis of Young's theory. (3)
In accordance with the above facts, when E. Rose brought for-
ward the evidence of his observations, Helmholtz at once
indicated the probable direction in which the statement of the
theory had to be modified. (4) Subsequently, Ilelmholtz's
pupils, Kijnig and Dieterici, working presumably under his
direction, made a crucial test to find if it were absolutely
essential to abandon the idea of lapse of a fundamental sensa-
tion, and found that it was necessary to do so. (5) Kimig in-
vestigated, at different parts of the spectrum, the mean error of
wave-length which could be made in adjusting light from
different near parts of the spectrum to equality. (6) Helmholtz
gave an expression, in terms of the unknown fundamentals, for
the rate at which the total " sensation " varies with wave-length.
He wrote down three linear equations, with unknown coeffi-
cients, expressing the three fundamental sensations in terms of
those chosen (arbitrarily so far) by Konig and Dieterici.
The latter were known in terms of the wave-length by
means of the observations of these two investigators.
Therefore, if Helmholtz could determine the unknown
coefficients, he could express the other fund.imentals in terms
of the wave-length. Now an obvious assumption to make is
this : the mean error of wave-length which can be m.ade in
adjusting two very narrow strips, one from each of two similar
spectra, to apparent equality corresponds to a constant differ-
ence of total "sensation." Helmholtz made this assumption
in order to determine the unknown coefficients by means of
Konig's observations on the mean error. And he fnither
justified this by showing that there w.as a close correspondence
between the mean errors found by Kiinig and the mean errors
calculated from his own theory on the assumption of a constant
difference of sensation. Thus the new fundamentals, given by
Helmholtz as " provisional," may be regarded as having been
determined upon a purely experimental basis, with no assump-
tion other than the radical assum| tion of three fundamental
sensations. The whole thing is a beautiful example of the
cautious, steady, scientific development of a theory. There
has not been, by Helmholtz, any violent upholding of a weak-
ened theory, followed by a sudden facing round after defeat.
In violet, or yellow blue, blindness, the two colours of the
spectrum are red and bluish-green, and the spectrum is short-
ened at the blue end with a sharp limit near the line G. Blind-
ness of this type is lare. The case described in this paper
presents the peculiarity that there is no shortening of the
.spectrum at either end. The range extends beyond the line a
at the red end, and beyond the line H at the violet end. The

NO. I318, VOL. 51]

33^

NA TURK

[January ^c, 1895

neutral point is near the line D, on the more refrangible side.
The maximum intensity of the red colour is reached at a point
near C on the less refrangible side, and the maximum intensity
of the green colour is reached at a point rather nearer to F
than the mid-distance from /■ lo F. There is no second
neutral point in the blue. It does not seem iha' ihe
phenomena can be readily, if at all, accounted for on Heiiny's
theory. On the other hand, it is easily accounted fur on the
^'oung•Helmhol•z theory by fusion of the fundamental sensa-
tions.— Ur. Xocl Paton read a paper, by Dr. John Douglas,
on metabolism in thyroid feeding. — Or, Richard Berry re->d a
paper on the anatomy of vermiform process and coerum. — Prof.
Tait communicated a paper on the ultimate slate of a system
of colliding particles, and the rate of approach to it.
Paris.
Academy cf Sciences. January 21. — M. Marey in the
chair. — On the variable star 6 (Algol) in Perseus, by M. K.
Tisserand. The author represents the variation in apparent
magnitude as being due to (l^ the e-vistence of one obscure
satellite with an elliptical orbit, and (2) a slight oblateness
of Ihe principal star, and shows that on these assumptions
the variation periods can be satisfactoiily represented
(.see "Our .\stromical Column"). — On boron steel, by
MM. H. Mnissan and G. Charpy. As Ihe result of a series of
comparative tests, it is found that boron (o'sS per cent, in alloy
uied) imparls the property of a great increase in tensile
strength by tempering without a corresponding increase of
hardness. .\ sample of carbon steel giving similar increase of
tensile strength on tempering, became so hard as 10 require
working on the emery-boh, whereas the boron-steel could siill
be worked with a file. — Morphology of the lymphatic system.
On the origin of the lymphatics in the skin of the frog, by M.
L. Ranvier. — On the perforation of armour.plates, by M. E.
Vallier. — On the production of the glycolytic ferment, by M. R.
Lcpine. The author is of opinion that the glycolytic ferment
is produced from diastase, lie relies on ihe increase of gly-
colytic power of pancreas when treated with ildute sulphuric
acid, in conjunction with the loss of saccharifying power and
gain of glycolytic power suffered by maltine when similarly
treated with rliluteacid. — /u'sumt' of solar observations, made at
the Royal Observatory of the Roman College, during the three
last quarters of 1894. A letier from M. P. Tacchini «ent to the
President. — On the convergence of determinants of infinite order
and of continued fractions, by M. H. von Koch. — Influence of
the rhythm of successions of interruptions on the sensitiveness
to light, by M. Chailes Henry. The investigation had for
object the determination of the sensitiveness of the eye to
interrupted light. rays of different types. The conclusion is
drawn that it is possible lo augment the luminous range of a
signal by means of a succession of interruijicd r.iys following a
sufficiently complex nnn rhythmic law. — Influence of tempera-
lure on the transformation of amorphous zinc sulphide, by M.
A. Villiers. — Failure of the Kjeldahl method for estimation of
nitrogen when applied to chloroplatinales, by M. iJelepine. In
Ihe cases of trimethylamine and ammonium plaiinochlorides,
the author finds by the permanganate modification of the
Kjeldahl process a considerable deficiency in ammonia obtained.
This deficiency is attributed to a reaction of free chlorine with
the ammonia, as follows :

(Nn,).jPtCI, + 3CI, = PtCl, + 8HCI + N,.
— (In arabinochloral and xylochloral, by M. Hanriot. — A new
synthesis of anthracene, by M. Delacre. Anthracene is pro-
duced from benzyl trichloracctate and benzene, by heating these
(obrtances in presence of aluminium chloride, and distilling the
resaltaot ether, when it decomposes giving carbon dioxi<le and
anihracene. — A contribution lo the study of Ihe ethereal salts
o( Ihe tartaric acids, by MM. Ph. .\. (luye and J. Fayollat. A
study of the rotatory power of nine of these esters in the light
of the theory of the product of asymmetry. — On a parasite of
Lampyrii iflenJiduIn, by M. A. Giuvel. The author names
the newly-described parasile Slyloj^ammui lamfyridis. — On
»ome bacteria from the Dinanlitn (Culm), by M. B. Renault.
— On Ihe development of sieve tubes in the Angiospernis, by M.
Chauvcand. The author concludes ihat (1) the rule of indirect
<levelopment of sieve-tubes is far from general. Both direct
and indirect methods of development may occur in the same
bundle. (2) The presence of companion cells is not absolutely
characleri.slic of the sieve-lubes of Angiosperms. — On the Chili-
Ar^cnline earthquake of October 27, 1S94, by M. A. F.
Nogucf. — Note on Uredo viliiiJa, by M, I.. Daille.

NO. I 3 18, VOL. 51]

BOOKS, PAMPHLETS, and SERIALS RECEIVFD.

Books. — A First Step in Euclid : T. G. Bradshaw (Macmillan).— Memoir
of Sir Andrew Crorntiie Ramsay : Sir A. Geikie (Macmillan).— A Hand-
book to the British Mammalia : R. Lvdekker (Allen) —The O.eal
Problem of SuKsiance and its Attributes (K. Paul). — .\ Travcrs le Cau-
case : E. I.cvier (Nenchatel. Attinper). — Forschuncsberichte aiis Her Bio-
lot;ischcn St.ition ^u Firm; Dr. O. Zacharias, Theil 3(Herlin. Friedl.inder).
— How 10 Live in Tropical Africa: t>r. J. Murray (Philip) — Field and
Garden Crops of the N.W.P. and Oudh : J. F Duthie, Part 3 (Roorkc).

Pami'HLEts — Sur la Nature et rOriginc de I'Aurore Bor^ale ; A.
Paulsen (Copcnhagne).— Der L'^sischc Algorithmus : J. Honthciin (Berlin,
Dames). — International BeginainKs of the Congo Free State: Dr. J. .\
Reeves (Baltimore).

Serials. — Journal of the Sanitary Institute, January (Stanford).-
National- Geographic Magazine. December 39 (Washington). — Transactions
of ti»e American Institute of Electrical Engineers, November and December
(New York). — linpenal University. College of .Agriculture. Bulletin Vol. ii
No. 3 ( I r.kyu). — Records of the Botanical Survey of India. Vol. i. Nos. 3
and 4 (Calcutta). — Psychological Review, January (Macmillan). — Monist,
January (Chicago), — Himmelund Erde. Januar>- (Berlin). — English Illus-
trated Magaiit.e. February (Strand). — Sundfty Magazine, Kebru.'U'y (Is-
bister) —Good Words. February llsbister). — Astrophysiral Journal,
January (Wesley). — Longman's Magarine, February (Longmans). — Cham-
bers's Journal, February (Chambers). — Observations Internationales
Pjlaires. 1882-3 Exixidition D.innise. Observations faite« a Godihaab.
tome i. livr. 2 (Copenhague). — Humanitarian, Febniary (Hutchinson). —
Natural Scier-:e, February ( -tait) —American Naturalist. January (Wes.
ley). — Journal of the College of Science, Imperial University, Japan,
vol. \ii. Parts 2 and 3 (TokyO). — Transactions of the Linnean Society of
London, Vol. '^v. Part a. On the Flora of Mount Ivinabalu in North
Borneo: Dr. O. Stapf (Linnean Society). — Ergebnisse der Beobachtungs-
stationen an den Deutscben iCusten uber die Phy.sikaltschen Eigenschafteti
der Ostsee und Nordsee und die Fischerei, Heft x-6 (Kiel, Lipsius).

CONTENTS.

PA Of

■ 3'.>

■ 3'7

Geo-Morphology- By Dr. J. W. Gregory

Organic Chemistry

Our Book Shelf:—

Wyalt : "British Birds: being Coloured Illustrations
of all the Species of Passerine Birds resident in
Ihe British Isles, with some Notes in reference to

Iheir Plumage" . . 31S

Na'ie' : ".Standard Methods in Physics and Elec-
tricity Criticised, and a Test for Electric Meters

Proposed."— W. W. . . 318

Slinao and Brooker : "Electrical Engineering, for

Electric 1 ight Artisans and Students" 31S

Orford : " Lens-Work for Amateurs " , . 318

Rolleston an I Kaniliack : " Manu,al of Practical

Mortiid .\nalotiiy" 318

Letters to the Editor:—

\ New Step in Statistical Science.— Francis Gallon,

F.R.S 319

The Kinetic Theory of G.'\ses. — G.H.Bryan 3m

Bolizmann's Minimum Function. — S. H. Burbury,

F.R.S 3.'0

Electroscopes in Lecture. — Prof. Oliver J. Lodge,

F.R.S 320

The I'erscid Meteors. — W. F. Denning . . , 320

The Artificial Spectrum Top. — Dr. F. W. Edridge-

Green ; Charles E. Benham 331

Snake Cannibalism.— H. Tsnagal 321

More A\)out Moths. -L. C. Jones J2I

The Physical Society's Abstracts of Physical

Papers from Foreign Sources 321

The Natural History of the Solway. liy G. Steward.

son Brady 322

Professor Arthur Cayley, F.R.S 323

Notes 323

Our Astronomical Column : —

The Natal Observatory 327

The New Duilley (Jb.servalory 327

The Milky Way 327

The System of .Mgol 328

The Explosive Nature of the Sodium and Potas-
sium Derivatives of Niiromethane. liy A. E.

Tutton • 328

Recent Work at Harvard College Observatory 329

Electric Discharge through Gases. (IlluUrattci.) By

Prof. J. J. Thomson, F.R S 3^0

University and Educational Intelligence 333

Scientific Serials 333

Societiea and Academies . . 334

Books, Pamphlets, and Serials Received ... 336

NA TURE

JO>

THURSDAY, FEBRUARY 7, 1895.

ARGON.

THE scene in the theatre of the University of London
on Thursday last was in many respects unique.
It will certainly be historical. It was unique in that the
Royal Society had formally invited members of two
other scientific bodies to attend the meeting, and had
left the comparative seclusion of Burlington House
to meet, in Builington Gardens, an audience numbering
at least eight hundred. It was the first of a series of
discussion meetings to which, we suppose, similar invi-
tations will be issued ; but it will be long before the same
eagerness to obtain a ticket is displayed — long before
those who gain admission, will listen to so much worth
hearing.

The previous history of the subject to be " discussed "
is known to most of our readers. Lord Rayleigh has
for some years been engaged on one of the most difficult
of physical measurements, namely, the determination of
the densities of some of the more permanent gases. In
the case of nitrogen, he was confronted with the fact
that if obtained from chemical compounds, it was about
one half per cent, lighter than if extracted from the
atmosphere. This result he published in the spring of
last year, and the cause of the discrepancy was a subject
of general conversation in scientific circles. Lord Ray-
leigh himself discussed it with some of his chemical
friends. Prof. Ramsay was interested, and since last
Thursday he has confided to an interviewer some details
as to the part he played in solving the problem. It
appears that he asked Lord Rayleigh's permission to
investigate the matter, that using a chemical method he
I succeeded in separating a heavier constituent from
I atmospheric nitrogen, and that on writing to Lord Ray-
leigh, he learned that he, too, had achieved, the same
result by a process of ''sparking."

The fact of the discovery was announced in a semi-
public way at the meeting of the British Association at
' Oxford. Of course it attracted great attention, and
curiosity was further stimulated by the silence of the dis-
coverers during the five succeeding months. Towards
j the end of last year it was announced that they would
give their results to the world in January. On Thursday
last the promise was fulfilled, and all that is known of
" Argon " was told to all.

Three papers were read, which showed that the period
of silence had been devoted to strenuous work. It was
proved beyond possibility of doubt or question that the
atmosphere contains a hitherto unknown constituent. It
has been separated from the air by atmulysis, by red-hot
magnesium, and by " sparking," Its density has been
determined to be about 197. It is very soluble in water,
and it has been proved that the nitrogen extracted from
rain-water is twice as rich in argon as that which exists
in the air.

Mr. Crookes has found that the new substance has
two spectra, marked by red and blue lines respectively.
Both he and Prof. Schuster certify that the principal lines
are identical in the case of two specimens obtained by
different methods. The properties at very low tempera-
NO. 1319, VOL. 51]

tures have been determined by Prof. K. Olsrewski, of
Cracow. The critical temperature is - 121° C, the critical
pressure 506 atmospheres. The liquid boils under a pres-
sure of 740-5m.m. at - 186--9, having at the boiling
point a density of about 1-5. The melting point is about
— 189" 6, and it has been frozen into a white solid
resembling ice. Last, but not least, the ratio of the
specific heats of the gas is approximately i 66, and all
attempts to induce it to enter into chemical combination
with other substances have up to the present entirely
failed.

After this torrent of well-established facts, it cannot
reasonably be doubted that Lord Rayleigh and Prof.
Ramsay have really discovered a substance, which,
though existing in enormous quantity, has hitherto
defied detection. Lord Rayleigh's work first showed
that there was something to explain ; the patience and
masterly skill which he displayed throughout years
devoted to weary weighings, must command universal
admiration. As has been well said, the result is " the
triumph of the last place of decimals," that is, of work
done so well that the worker knew that he could not be
wrong. Prof. Ramsay, too, is to be congratulated in that
when this preliminary stage had been accomplished, his
energy and skill enabled him to take such a share in the
hunt after the unknown cause of the difficulty, that he
rightly ranks as a co-discoverer of the new gas.

In scientific invisstigations, however, the answer to
one question always suggests others, and interest in a
discovery quickly precipitates into interest in its results.
Seldom have a series of facts and figuies raised more '
important issues. The ratio of the specific heats is I •66,
which points to the conclusion that the substance is
monatomic. If it is monatomic, it must be an element
or a mi.\ture of elements. If it is a single element, its
atomic weight must be about 40, and m that case no
place is ready for it in Mendeldefi''s table. The easiest
way out of the difficulty is to suppose that argon is a
mixture, and the authors point out that there is evidence
for and against this view ; " for, owing to Mr. Crookes
observations of the dual character of its spectrum ;
against, because of Prof. Olszewski's statement that it
has a definite melting point, a definite boilmg point, and
a definite critical temperature and pressure ; and because
on compressing the gas in presence of its liquid, pressure
remains sensibly constant until all gas has condensed to
liquid. The latter experiments are the well-known
criteria of a pure substance, the former is not known
with certainty to be characteristic of a mixture." The
question is to be further investigated, but at present the
authors conclude that the balance of evidence is in
favour of simplicity.

On this hypothesis a very awkward question is no
doubt raised. The periodic classification of the elements
cannot, and ought not, to be abandoned at the first
challenge, and till further evidence is forthcoming a
heavy strain is thrown on the link of the chain of argu-
ment which connects the ratio of the specific heats with
the monalomicity of the gas.

On the other hand, the conclusion that if the ratio of
the specific heats is 166 the gas can be diatomic, is
directly contrary to all .analogy. Merely to say that
mercury is monatomic, that Kundt found that the

Q

;3S

NA TURE

[February 7, 1895

ratio of the specific heats is one and two-thirds, and
that therefore a similar relation must hold for argon, is
to understate the case. Taking the very outside values,
no diatomic gas has a ratio greater than about \\i ;
and to place among these a substance for which the
ratio is i"66, would be entirely opposed to all the
other indications of a theory which, though ad-
mittedly only approximate, nevertheless in all other
cases accords fairly wiih the conceptions of the
chemist. The behaviour of mercury vapour suggests
that there are two classes of phenomena which occur
within the molecule — a coarser group with which the
ordinary mechanical theory of gases is concerned, and
a more refined type detected by the spectroscope. It is
the former, and not the latter, which are of the same
order as the chemical facts which lead to conclusions as
to the number of atoms in the molecule.

Thus, in the case of mercury vapour, the mechanical
theory of gases ignores the vibrations, whether
mechanical or electrical, which produce the spectrum,
and gives the precise value of the ratio of the
specific heats which corresponds to three degrees of
freedom. Whe;her we frame a mental picture of a
Boscovitch point, or are content with the more usual
contradictory image of a smooth sphere, perfectly elastic,
and yet incapable of internal vibrations, is for the present
purpose comparatively unimportant. It is impossible to
connect the conception of three degrees of freedom with
anything that does not behave as one single thing, in-
capable of being set in rotation, and incapable of internal
vibration. That such a thing may have structure is not
denied. It is only affirmed that as far as the phenomena
under investigation are concerned, structure is not
recognisable. It is not denied that it may be subject to
internal changes. It is only affirmed that these changes
are of different order from the causes which affect the
behaviour of the molecule in what may be called
the pressure-producing machinery of a gas. Where
the ordinary dynamical theory stops, there, and there
precisely, chemical analysis stops also. The chemical
facts which prove that mercury is monatomic have
nothing to do with its spectrum. The arguments used
would be valid if it had no spectrum at all. Analysis
recognises no structure in the indivisible molecule of
mercury. In chemistry, and in the approximate theory
of gases, "monatomic" means — in this case, at all
events— the same thing.

.\cxt take the case of the diatomic gases.
The results of the dynamical theory can be most easily
represented if we suppose the atoms to be smooth spheres,
which may, if it is desired, be regarded as mere gco-
incincal surfaces surrounding Boscovitch centres.

The theory shows that unless the two atoms when
united can be fairly represented by a single point or a
single smooth sphere, the ratio of the specific heats ought
not to be greater, but may be less, than 1-4. This value
would correspond to the case of two smooth spheres the
surfaces of which were maintained in contact, or to two
points maintained at a certain fixed distance apart, but
■ itherwisc free. Smaller values would indicate greater
internal freedom.

The gases may be divided into two classes, viz.
firstly, 0.,Nj, H„ CO, NO and HCI, and secondly, CI.,,
NO. 1319. VOL. 51]

Br, and r,. The mean of the ratios of the specific heats
for the first six is, according to Masson,' i'399. The
corresponding figure deduced from Kegnauli's experi-
ments is I '410. The highest value obtained from
Regnault is 142 in the case of HCI, but Masson's value
for the same gas is only vy)Z, the mean being i 406. In
the cases of CL, Br^, and L the values are lower, lying
between i'293 and I'S^s. The larger values thus ir»
some cases slightly exceed, but are in all cases very
close to, the limit fixed by the theory on the assump-
tion that the dual character of the molecule can be
recognised by it. The smaller values fall well within the
limit.

The ratio of the specific heats has not been directly
determined for many substances, but it can be calcu-
lated by well-known formuUc for all gases of which
the specific heat at constant pressure is known,
and though the values thus obtained are only ap-
proximate, they are sufficient to prove that the mole-
cules of the more complex gases have always more
than the minimum number of degrees of freedom which
are consistent with the idea of their being built of
smooth spheres constrained to remain in cont.ict, and
equ.il in number to the number of atoms within the
molecule. Whereas, if argon is a diatomic substance,
the molecule has f^wer degrees of freedom than the
theory indicates, and is thus the single exception to a
universal rule. In that event it is not too much to
say that the result will indicate a connection between its
atoms of a kind absolutely different from that in any other
known substance. In all other cases the approximate
dynamical theory is in close agreement with tlie view that
molecular structures made up of the union of two or more
like or unhke things, have a more or less irregular form,
and are capable of rotation. If argon is not monatomic,
this rule will for the first time be broken. Quite apart
from the absolute validity of the theoretical grounds on
which it is based, and regarded only as suggested and
not as completely justified by theory, it is nevertheless
an empirical generalisation which up to the present has
stood every test.

It is not suflicient to explain the difficulty by saying
that the bonds between the constituents of the argon mole-
cules must be very s:rong, for we have already assumed
that the tie which unites the centres of the hydrogen
or oxygen atoms is proof against the collisions which
occur in the gas — i.e. is or the purposes of the approxi-
mate theory infinitely strong. It is further necessary
that the molecule must be incapable of rotation, that
the two points must coincide, or the two spheres be
crushed out of shape, so that the surface is spherical.
Such violent assumptions would be quite unjustifiable
unless we are driven to them by facts which cannot be
disputed. . Until it is directly proved that argon is
diatomic, we must agree with the discoverers that the
weight of evidence is in favour of the molecule being
indivisible. Whether in the future other and more
convincing evidence will be adduced on the other
side, the future alone can show. The courts of science
are always open, and every litigant has an unrestricted
right of moving for a writ of error.

Sec K. Strcckcr. Wieii. Ann, 1 (, 1881, p. 41.

February 7, 1S95J

NA TURE

.39

A TEXT-BOOK OF BOTANY.
Lehrbiich tier Botanil:. By Drs. E. Strasburger, F. Xoll,
H. Schenck, and A. F. W. Sthimper. (Jena ; Fischer,
1894.)

THIS book is intended for the use of students in the
German Hochschulen : throughout it is written in
a manner whicli is at once interesting and exact. Ac-
cording to the usual plan adopted in text-books of the
kind, it is divided into two parts - the first dealing with
general botany, and the second with special botany. In
a general introduction a short rrsuini' is given of the
theories of descent and of natural selection, with a view
to their bearing on the subject of the natural boundary
between the animal and vegetable kingdoms.

The first division of the first part is devoted to the
general morphology of plants. It is written by Prof
Strasburger. This whole subject he treats from a phylo-
genetic point of view, and so renders, what is in many
botanies little more than a list of difficult names and
their explanations, extremely interesting and suggestive
reading. A good example of this will be found in his
account (p. 26) of the leafy stipules of Lathyrus apliaca.
In this connection it may be noticed that having once
described the more important forms, he does not enlarge
on the very various shapes and modifications assumed by
leaves, stems, &c., as is often done in text-books, where
the writers often appear to glory in the number of curious
terms they collect descriptive of the forms of the
members of plants — terms which, if it is necesrary for
the student to learn, might be more easily mastered if
printed as a kind of botanical vocabulary or glossary,
instead of rendering such an attractive subject as vege-
table morphology a monotonous exercise of the memory.
In the portion devoted to anatomy and histology we find
the structure of the cell and its contents extremely lucidly
described. The digression on p. 45, with regard to some \
of the properties of protoplasm and the eft'ect of high |
temperatures and of reagents upon it, might have, j
perhaps, come more appropriately in the part of the
book allotted to physiology. In the account of the
systems of tissues in vascular plants, and their morpho-
logy, we are furnished with the results of recent work in
this direction, of which so much is due to the author's
own researches. With regard to the origin of these
tissues, he disputes the theory according to which the
meristematic apex of the stems and roots of phanero-
gamic plants is difterentiated into three distinct initial
layers. He urges that the arrangement of the cells in
these regions is rather due to mechanical causes, and
that the terms Dermatogen, Plerome, and Periblem
should be used simply to facilitate the description of
certain cell-layers in the vegetative cone, without in-
volving the idea of the presence of distinct Histogens, as
they have been called. Throughout this whole portion
on general morphology, we feel that the space has
been too limited, and we wish that the author had not
restricted himself to the 126 pages allotted, but had
allowed himself to enter more fully on the numerous
points of interest in this subject which he, perhaps
beyond all others, is capable of discussing.

The same remark may also apply to Dr. Noll's part
on physiology. It is throughout too much abbreviated.
NO, 1319, VOL. 51]

Apart from this defect, which is involved in the nature of
the book, it is very .attractively written, and by its
logical arrangement and clear descriptions does much to
atone for the necessary crowding of facts. The chapter
on the phenomena of movement in plants strikes us as
suffering the least from the condensed nature of the
writing, and seems to be a good account of both earlier
and recent researches on the subject.

The special botany is the work of Dr. .Schenck and
Prof. Schimper. The classification adopted is that pro-
posed by Braun, and elaborated by Eichler and others.
Little need be said of this portion, except that much
trouble appears to have been taken to make the descrip-
tions, so far as possible, include the results of modern
work. At the end of the book there is a list of medicinal
and of poisonous plants, as well as a very complete index.
It is to be regretted that the authors have not given some
references to the literature of the subjects of which they
treat, so that the student might be helped to pursue more
fully his studies in the directions he desired. The book
is throughout profusely illustrated by means of extremely
good figures, many of which are tastefully coloured. The
figures are, to a large extent, new, and those which are
not specially designed for the book are well selected, in
part, from Prof. Strasburger's other works and, in part,
from sources which are not commonly familiar to English
readers, so that in this way the value of the book is
enhanced. With regard to the coloured figures, they
have this novelty — that they are inserted in the text, and
are not in the form of separate plates. H. H. D.

A^ NEW POPULAR BOOK ON BRITISH
BUTTERFLIES AND MOTHS..

Butterflies and Moths {Brilisli). By W. Furneaux,
F.R.G.S., author of " The Outdoor World, or Young
Collector's Handbook." With twelve coloured plates,
and numerous illustrations in the text. (London :
Longmans, Green, and Co., 1S94.)

THE success of Mr. Furneaux's " Out-door World"
was sufficiently marked to induce the publishers to
make it the first of a series of popular illustrated works
on British Natural History,tobe called "The Out-door
World Library." Of this series, the volume before us
forms the second ; and we observe that others are pro-
jected, on British Birds, Mammals and Reptiles, Pond-
Life, &c.

This is pre-eminently a beginner's book, written in a
popular style throughout, and it has also been nicely
printed and illustrated, so as to make it as attractive-
looking as possible. Hence the practical part of the
subject is dealt with at length, while questions of a purely
academic nature, such as synonymy, are wisely omitted
almost entirely. English names are given the most
prominent place ; but the scientific names used in Soulh's
List are added in brackets.

The book is divided into four parts : Structure and
Life-history of the Lepidoptera ; Work at home and
in the field ; British Butterflies ; and Common British
Moths. The appendices include a list of British Macro-
Lepidoptera according to South's " Synonymic List," as
far as the end of the Gcomctrida (the English names
here being in brackets), and a Lepidopterist's Calendar.

340

NA TURE

[lliliRUAKY 7, 1S95

The ir.tro i ictory chanters are very good, and the
woodcuts are c'e\r an 1 instructive, especially that of the
neuration nf a butterfly, on p. 9. We cou'd have wished
that Mr. Furneaux hid had space to treat of such im-
portant suSjicts as neurition and the scaling of the
wings m 're fully. The early stages of Lepidaptera are
also discussed and illustrated ; and we notice that our
author ca'ls the head of a caterpillar the "first seg-
ment." We know that some hypercritical authors object
to the held of an insect being called a segment, because
it is morph ilogically considered to be made up of so
many "simites." But to refuse to allow the head of an
insect to be called the first segment (in the case of cater-
pillars, at lea^t) appears to us as absurd as it would be
to object to the skull being spoken of collectively, because
it is morphologically regarded as composed of a number
of mod fied verlebr.x. On the other hand, we think that
Mr. Furneaux has been injudicious in calling the five
membranous pairs of legs of a caterpillar " claspers,''
a term properly applicable to the last pair only. We
think the usual distinction made between the last
pair and the others should be preserved in speaking
of them, though the term by which the other legs are
generally known (prolegs) is perhaps not quite correct.

The directions for collecting and preserving appear
to have been written by an experienced practical col-
lector, with his heart in his work. However, when insects
are set tlat. the groove is generally made deeper than is
shown in the illustrations on p. 123. The advice to start
at once with a cabinet, spaced out for all species, may be
very good for those who can afford to buy a large cabinet
offhand ; but many of Mr. Furneaux's readers will cer-
tainly find it too costly, and we fear that any beginner who
commences in such a manner will find his patience ex-
hausted at his slow progress, and might give up the study
of insects prematurely in disgust.

No technical characters are given for species, genera,
or even families ; and, strangely enough, the .Seraphims
\Lobophora) are said to differ from the I'ugs {Eupi-
thtcia) by their" covering their hind-wings when at rest '' ;
no mention being made of the curious appendages to the
hind-wings of the males in Lobophora, which gives them
the appearance of having six wings, and has suggested
the name of " .Seraphims."

Generally speaking, however, the accounts of the
\arious species discussed (all the butterflies and a good
series of representative moths, at least among the Macro-
I.cpidoptera) are very good. Mere and there, however,
we meet with a doubtful statement, as that " the Dlack-
veined White is hardly to be distinguished from the
Common Large White on the wing." Those accustomed
to see both would hardly confound them, nor would the
former frequent open ground at a distance from trees.

The numerous woodcuts are of unequal merit, but
a fair standard of excellence is maintained throughout,
and most of them arc easily recognisable. The coloured
plates, though recognisable too, are, we regret to say, not
up to the standard of the woodcuts. Sometimes the
colour is inaccurate, as in the case of the Purple
Kmpcror, which has been represented as lilac rather
than blue. It is, of course, a difficult insect to figure,
but has been represented better in many popular bcoks
of late years. In the tirst two plates, an attempt has
NO. 1319. VOL. 51]

been made to throw up the colour of the insects (mostly
whiles and yellows) by shading. This has given rise to
the appearance of an ugly smoky rim round the figures:
and the experiment has been wisely abandoned m the
remaining plates. We regret this the more, as the
desired eflTect has been admirably attained by using a
tinted background in Prof. Aurivillius' recent work on
the butterflies and moths of Northern Europe; and we
should like to see this improvement introduced into
other books of a similar kind.

W. F. KiRBY.

OUR BOOK SHELF.

Die Resultate der Aetzmethode in der krystallograph-
ischcn Forschuns;, an einer Rcihe von kryslallisirtett
Korperndar^^estellt. Von Dr. H. H.iumhauer. Mit 21
Texifiguren und einer iMappe mit 48 Mikrogrammen
auf 12 T.ifeln in Lichldrnck. Pp. 131. (Leipzig:
Wi;helm Engelmann, 1S94.)

It has long been known that the action of a reagent
upon a smooth plane surface of a mineral substance may
reveal details oi structure previously invisible, and that
such a mode of investigation has been extiemely useful
in the case of meteoric iron ; indeed, the method is
particularly valuable in that case by reason of the fact

th:it the structure thus revealed is dilleieni fiom the
structure of terrestrial iron.

The researches of Leydolt, Baumhaucr, and others,
have shown us that the figures produced by reagents on
the faces of the crystals which aie met with among
minerals, or are artificially prepared by the chemist,
though dependent on the kind and strength of the re-
agent, are \el characteiiscd by a symmetry which con-
forms with'that of the crystalline structure ; further, the
etched figures serve to indicate by their forms the par-
ticular kind of symmetry (holosymmetry, hcmisymmetry
tctartosymmetry, twinning) belonging to the crystalline
structure, in many cases where other characters, physical
or morphological, are insufficient for the purpose ; they
are especially useful in the investigation of isomorphism.

The etched figures can be observed, for instance,
in the case of a crystal of which the opacity renders
investigation by means of transmitted polarised light
impossible ; and, even in the case of a transparent

February 7, 1895 J

NATURE

541

•crystal, they often serve to determine the particular type
■of symmetry to which the structure belongs when
polarised light may merely indicate whether the crystal
is op'ically isotropic,uniaxal, or biaxal. Dr. liiumhauer
has done a greit service by preparing for publication
a series of mignified phjtographs of the figures
produced by etching different faces of crystals of
the following subu incei :^FIuor, Blende, Cryolite,
Apatite, Nepheline, Datolite, Zinnw ildite, Le;icite, Bora-
cite, Dolomue, M ignesite, Chalybite, Nickel sulphate,
Strychnine sulphate.

The figure on the previous page shows the hexagon-
ality of the depressions which, alter etching, are seen on
41 basal plane of a crystal of Apitite.

These beauiifully executed photographs 'are accom-
panied by detailed descriptions (85 pp.), and by a sketch
of the history and development of the methods ("46 pp.).
Dr. Baumhauer has done such excellt-nt work in this
branch ot science, that he is parti ularly qualified to
select and describe examples which illustrate the poten-
tiality of this mode o( investigating crystalline structure.
The photographs are mounted on twelve separate plates,
so that they may be conveniently used in the class-
room.

Suiinner Studies of Birds and Bonks. By '.V. Warde
Fowler. Pp. 288. (London: Macmillan and Co.,
1895.)
Forest Birds ; their Haunts and Habits. By Harry F.
Witherby. Pp. 98. (London : Kegan Paul, Trench,
Tiiibner, and Co., 1 89+.)

It would be difficult to find a worthier disciple of Gilbert
White than Mr. Warde Fowler. Many of While's most
exact and enduring ob5ervations were made on birds,
and the " Natural History of Selborne " has furnished his
imitators with descriptions of the characteristics of the
Stone-curlew, the Ring-ousel, the House-martin, the
Sand-martin, the Goat-sucker, and many more of the
birds of which he recorded the habits and movements.
Hut Mr. Fowler's writings are not mere paraphrases of
his prototypes. He is gifted with the " nice observation
and discernment '' required by every student of nature;
and he can express himself in attractive language —
attractive because it is unaffected, and because it is devoid
of thin sentiment and gush. The result is that the pspers
reprinted in this volume are reahy valuable contributions
to ornithology. To remark that there is not a dull page
in the book may be a trite saying; nevertheless, so far as
I we are concerned, it is a true one in this case. What
1 could be more readable than the chapters on the birds of
the Engstlen Alp, and the birds of Wales : and where
will you t^.nd a better example of careful and painstaking
observation than is afforded by the account of the
Marsh Warbler in Oxfordshire and Switzerland?
The chapter on the songs of birds is most interest-
ing ; that descriptive of Aristotle's writings on birds,
(in which fact and fiction are given equal prominence),
should be read by all naturalists ; and the bingrnphy of
Gilbert White shows that the author is saturated with the
spirit of the naturalist whose work has had such a wide
influence upon natural history during the last hundred
years.

Little more need be said about this charming book. So
many volumes on popular natural history have lately
appeared, that the subject has probably begun to pal!
upon the public taste. Mr. Warde Fowler's work, how-
ever, is so full of interest ; it breathes out the air of the
fields and streams so pleasantly, that it carries its own
welcome to the heart of every lover of nature.

The second of the two books of which the titles are
given above, is of quite a dilTerent character from the
first. It is remarkably well illustrated, is daintily bound,
and is nicely printed, and therefore it forms an attrac-
tive volume, so far as appearances go. But the text is

NO. 1319, VOL. 51]

dull ; for the author, while possessing the essential love
of nature, lacks the words with which to express it
eloquently. To him, "the Stork Dove is f.urteen
inclies in length from the tip of the beak to the end of
the tail, and its stretch of wing is twenty-six inches. Its
general colour is bluish-grey. The head, wings, and
back are of this colour, and the tail is the same, but
tipped with leaden grey." There is much more of the
same kind in the book ; and we confess that after read-
ing Mr. Warde Fowler's smooth phrases, Mr. Wuherby's
composition appears spiritless. The illustrations, how-
ever, are g )oJ e lou ^h to m ike up for deficiencies of the
text, and for their sake alone, the book is worth buying.

LETTERS TO THE EDITOR.

\_The Editor tioei not hold himself responsible for opinions ex-
pressed by his correspondents. N.ither can he undertake
to return, or to corresponl with the writers of rejected
manuscripts intended for this or any other part of Na I'URE.
No notice is tat:en of anonymous communications.]

On the Age of the Earth.

In reference to Lord Kelvin's leiter (Nature, January 3,
p. 227), he will, no doul)t, presently communicate »i h you on
the results of measurements which he is miking on conductivity
and temperature in rocks. I do not wish 10 foicslall bim by
referring at present to his more recent correspondence wiih me.
Three weeks ago I sent him the solution of the problem of a
cooling sphere whose cinductivity i and volumeiric capacity c
are any functions whatsoever of the temperature z; hut which
are always pr>p jrtional to one ano'her. As Mr. lleaviside
hal been writing to me, and had shown me that under certain
circumstances the differential equation became linear, and as I
had used his operators much a."; he himself uses the n, I cannot
say to what extent I cm claim credit for the work. I now venture
to stnJ you the more general case.

If

/'

dv = K

(I)

so that » is the total amount of sensible heat in unit volume.
The general equation is

^^(h'^-^\ + l(h±\ + !L/i'^'!\ = '^"

{(h'^l\ + l(i±\ + !L(i'^^] = ^' . . . (2)
x\ dx) dy\ dy) d\ dz) dt

Now let k = CK where k is a constant, then

and the equation becomes

dit du

K — as <r =
dv dv'

d'^u dht d'^u _ I du
dx- dy- dz- k dt

.(3)

Any of the many problems that have been worked out oB
the distribution of u may be translated in'o temperature pro-
blems. Thus in a body before / = o let k = k, a constant
everywhere, and after / = o let the suitace have eveijAheie a
constant a = h„. Let ihe solution be

« = («, - H,)F (X, y,z,t) .... (4)

In the boiy before / = o let w = o, a constant everywhere,
and alter ? — o let the >urface have everywhere v - Vi, a con-
stant, then if ?/is the temperature anywhere

. . .(5)

jc . 'lv = (h, - Ho) / (x, y, z, I)

so that a table of the values of (r . r/o enables the tempera-
ture at any place to be calculated.

If - the rate of increase of u normally inward from the
dn
surface at any place, has been calculated, say that it is

du

dn

= («, - «o)F(-r, J-, s, ')

(6)

NATURE

[February 7, 1895

du _ du dv _ dx'
dn do' dn ^"

du

= 5-=—,

"F(x, y, z, t)

.(7)

where ^ is the temperature gra iient inwards from the surface,
and Co is the value of < at the surface.

If c'andi( are on^tant everywhere, «ay Cj and /•(!> let us call
the surface gradient i:^ : then SlS u = c„v ^ C

i = I "• ~ v±,

for the same place at the same time after cooling began.
As an example, let

k = kjiflv + I),
and

^ = ./..:■+ I),

and measure v on the CeniigraHe scale, c„ andX'^ are the actual
capacities and conductivities at o*^ C. ,

II = t-,(i<K^ + •< + C),

_ ia»,- + I'l _

iac, + I.

Thus if ^ and <(' increase ; per cent, per lOo degrees Cenii
grade, and iff, = 4000, as

a = xo'-'s. K = L + I.

In the cooling of Lord Kelvin's infinite mas; with a plane
face the time which elapses until a pariicul.ir STirfice grail ient
is reached is inversely proportional to the s piare of thegraHjeni.
If the lime tak»n on the assamption of constant <" and k be
called /„, and if the time taken on the assumption that c an I <■
increase ; per cent, for 100 degrees is /, then

//'.

Suppose
then

s = so,
///,, = 121.

So that Lord Kelvin's age of the Earth would be muliiplied
by 121.

It mu^t be understood that my conclusions (KATtJRE, January
3i p. 224) are really independent of whether R. Weber's results
are correct or not. Lord Kelvin has to prove the impo'sihiliiy of
the rocks inside ihe ?arth tieini; better conductors (including con-
veclive conduction in case of liquid rock in crevices) than the
surface rocks. If, however, Weber's results, as quoted by me,
are trustworthy, the above solution is what I take Luid Kelvin to
refer to in Ihe first paragraph of his publi-hed letter. In con-
sidering all such measurements as those of K. Weber, it must he
remembered Ihat the rocks at twenty miiesdeep ate not merely
at a hit-h li-mperalure, but also under great pressure.

January 30. John Perry.

Oceanic Temperatures at Different Depths.

Thk que«tion of the pcrsislcnce or otherwise of the tempera-
tare of diflTcrcnt strata o( water beneath the surface of the
oceans, is one upon which so few observations have been made,
thai it will probably be imcesling to students of oceanic phe-
nomena 10 publish in NAitni. the results obtained at one spot
in the Atlantic, at periods extending over as much as twenty-
one years.

At a position about 200 miles west south-west from Cipe
Palmas, in Africa, where the depth of water is about 2500
fathoms, and where on the surface the Guinea current is run-
ning 10 the eastward, the Chalhn^ r in 1873 and 1876, the
lliucanitr in 18S6, and the H'a/enviU/i in 1894, have all
obtained serial temperatures ; the firjt three to a depth of 200
fathoms, Ihe last 10 150 fathoms.

The result is given in ihe following table, and illustrated by
the diagram.

NO. 13 19. VOL. 5 1]

Coiiif arisen pf Ouaii Ttmpiratures ohiaiiicd at Different TimeF
in or near the same position, viz. 5 48' jV., 14° zo' IV.

Bticcanet'r

Depth in ChatlcMger I CiaUr«gtr I

r-iihnm^ lemprrtliires, temperatures,' tcmperalures,

Surface

79 '2

S3 -5

10

—

83-2

20

—

70-0

25

72-6

—

30

—

626

40

—

60 'O

50

625

59 2

60

5S-S

70

57'S

75

5SS

80

—

57-1

90

—

565

100

562

55 9

1 10

—

55-2

120

—

546

'25

541

—

130

—

54 -o

140

—

53 3

IsO

522

52-7

160

52 '

170

—

51 4

iSo

—

508

190

—

501

200

483

49 5

S2S

796

69-0

65-9
608
5SS

561

temperatures,

22/9/94.

Soo
780

752
69-2
62-8
602

58-8

570

490

li.^cad Positions and Observation Spot.
Challenger,

•9/S/73
Challen^'er,

Lat

54SN- .

Long.

14 20 W

10/4/76

5 28

"4 38

Buccaneer,

W'alenvilcii,

5 4S

14 20

22/9/94

5 48

14 22

0 20 40 60 80 100 120 140 160 180 20»

Diagram shuwiiig temperature at different depths obtained at variout epochs
ta I.at. 5 48' N., Long. 14" 20' W.

It will be observed that Ihe tcnpcratures at the surface vary
by 6 '3 1". ; at a depth of 20 (allioins. by 9 '6; at 40 fathoms.

February 7, 1895J

NA TURE

^ A *>

by about 6° ; at 50 fathoms, by 3°7 ; while at lOO fathoms,
three of the resi:lts are wiihin o°'3 of one another, the fourth
being l'"l ahove the lowest. From ico to 200 f;ithom=, the
temperaiureF, diminishing in the same ratio, differ by about the
same amount.

It is HiflTicult to 'ay exactly what value can be placed on each
individual observation. Many small errors may creep in ;
errors of reading, errors from movement of the indices, errors
from insufficient time heing given for the insirumewc to take up
the true temperature, &c.

These should not, however, reach a degree in any instance,
and it is pretty plain that below 100 fathoms the temperature at
this spot remains fairly equable. This confirms the general view
held by Iho^e who have studied the results obtained from obser-
vations at different depths, in different parts of the ocean.

While from one point of view it is unfortunate that the
observations have been lalen in different months, on the other
band, the vaiiation in the surface temperature at different
seasons of the year is given full value in the comparison.

January 26. \V. J. L. Wharton.

"The Bird- Winged Butterflies of the East."
Permit me to add a few notes supplementary to the very
interesting and able article, by my friend Mr. Kirby, entitled
" The Bird-Winged Butterflies of the East," which appeared in
your issue of January 10, p. 254.

(0 If the male of eiher of the two species of my genus
/Jithci^ftera is examined in the proper light atid position, a long
pupse form stigma, composed of raised scent- producing scales, will
be very readily seen, of a more slender character, but in nearly
the same relative position on the hind margin of the anterior
wing, as in the males of the genus Otiii/lio/'lera, or, as Mr.
Kirliy pnfers to call it, Ttoi'les. As I have pointed out in
part viii. of my " Icones Ornithopterorum," this stigmatic
sexual brand, being a densely black mark surrounded by the
general velvet black of the wing, is very likely to be overlooked
by a casual ob-erver in some positions, while it is really very
prominent in others ; and I have called special attention to the
lovely arrangements by which the lattrr result is attained ; and
a reference to the plates containing the figures of these species
will suffice to show how very obtrusive the mark is, and how
much more beautiful the insect I'ecomes by the magical play of
opalescent tints on the black which encloses the sti^jma, as the
insect is moved into different positions against or opposite the
light. To sim[>ly look at the insect as it 'tands iti a cabinet
drawer, is to mi-s all this glory and its raison d'flrc. As in all
the species of Ointthoptera, the female p"ssesses no such organ.

(2) ^K. (?) Tithoiivi ' Dc Haan), as quoted by Mr. Kirby, is (as
he cvidtntly suspect ) not a memter of the genus . Ethcot'tera at
all, but belongs to the first genus of the tfue Ornithopien, viz.
Schoenbergia(i,\x\> genus of Pagen^techer, and genus of A'///o«) ;
and 1 have no doubt that the female hutteifly supposed to be its
mate, is rightly assigned 10 it, as it is singularly like the female of
Sch. Parailiifit of Staudinger, and also co generic with the
large form described by M. Ch. Oberthur under the name
O. Goliath. Neither in ScIi Paradista or S<h. Tithoiius is the
male furntshcd with a pup^form sexual mark as in Ornithoptera
and .^itheoplera^ nor with an abdominal marginal pouch or
fold concealing the nndrocoiiia, as in the males of Po/iipcoptera,
or a-s Mr. Kiriy calls them, OniitliopUra and 7^roi^oitopteya.

(3) I am compelled to regard the Ornithoptera as being
naturally divided into three sub groups of unequal extent (so
far as our present material indicates): (i) The African or
Acraoid Ornithoptera, containing one genus {/)riirya), and two
specie", D. Anlinuuhui (Drury), and D. /ialmoxis of Hewitson ;
(2) the Oriental or true Ornithoptera, with the five genera
ScAoenieriia, OruilUoftera, ^El/icoptirra, Troi^onoptera, and
Pompioplera ; (3) the South and Central American Ornithop-
Urina^ coiraining the numerous black and red, and black and
green, and olive black Papilios, which are usually allowed to
follow the true Ornithoptera in our systematic catalogues. The
males of many of these possess an abdominal marginal fold
concealing the androconia^ an organ not found, as far as I am
awaie, on the abdominal n.argin of any other section of the
Papilionida: — though the sexual stigma can be found on the
anterior wings of several males, as tn P. Ulysses for example,
though differing in form and position.

(4) My re.aMins for not adopting Ilubner's name Troides in
place of Orttilhoflera for the Pnanius group will be founil by
referring to "Icones Ornithopterorum." .\t the same lime, I

NO. I319, VOL. 51]

quite understand, and to some extent sympathise, with the severe
and uncompromising appliciiion of the law of priority in
nomenclature for which .Mr. Kirby and several other naturalists
contend.

(5) The wonderful iridescence of the yellow hind wings of
Poinfenplera Magcllaiius, <J , may be seen equally displayed on
the unrter surface also.

Finally, I may safely say that the males of yEthcoflera and
Schotiibergia are pro'iably the most perfectly beautiful of the
butterflies of the world. ROBERT H. F. Rippon.

Upper Norwood, .S.E., January 19.

Thirst-endurance in some Vertebrates.

Whe.n an example of great ability to endure thirst is desired,
the camel is usually suggested. Hibernating animals also are
put forward in instance of existence without water for long
periods. The camel carries a supply with it, so that what is
most wonderful in its case is the tank. Torpid animals need
little or no moisture beyonH that in their systems, and, besides,
they benefit from dampness around them. Better examples
abound on the arid plains near the Rocky Mountains and the
Sierras, in the innumerable active, noisy little rodents, miles
away from streams or pools, and out of possible reach of water
by burrowing. Any one who observes these creatures in their
haunts in midsummer, will be pretty sure to inquire, like one of
my companions, " What do those little wretches get to drink,
anyhow?" The only reply appears to be, "They drink water
when they gel it, and do without at other limes," For
weeks and months, when the vegetation is shrivelled and parched,
and the sand^ are at iheir hottest, these squirrels and their
neighbours, with thickening blood, wait for the rain, that the
currents in their veins may be thinned and quickened. But
one need not go so far for a much belter instance than the
camel. The common mouse endures thirst quite as well as its
allies in the desert. This has been proved rcpea edly by mice
kept here as a reserve supply of food for a lot of reptiles. Re-
ducing the allowance of water prevented the foul odour by which
mice are generally attended ; this leil to keeping some of them
entirely without water, to note the effect. Last winter, a few
were kept in a warm room more than three months before being
fed to the snakes. On the first of last October, several were put
aside to have no drink ; at the lime of writing, three months
and a half later, they are eating heartily of the dryest of maize
and grass seeds, on which alone they have been fed, and they
act as if able to endure the experiment a month orlwo longer,

S, Garman.

Cambridge, Mass,, U,S,.-\., January 17,

Electroscopes in Lecture,

The electroscope which Prof, Lodge proposes to use to indi-
cate pcisitive and negative potentials hy different movements of
the leaves (see p, 320), has the disadvantage that (assuming the
case to be charged negatively), if too large a negative charge be
given to the gold leaves they will diverge, and the inference
will be that the potential is zero or positive, neither of which
is the truth. For the purpose Prof, Lodge has in view, a
Bohnenberger's electroscope would indicate more clearly posi-
tive, negative, or zero potential. Instead of the two dry piles,
the inner and outer coatings of a charged insulated Leyden jar
connected to two knoh.s, one on each side of the single gold
leaf, might be substituted. J. Reginald .\SHwnRTH.

The Owens College, Manchester.

Snake Cannibalisin.

Thk notice in Nature, January 31, p. 321, on the above-
mentioned subject, calls to my mind the following passage in
Rcnan's " .\verroe-," Paris, 1867, p. 310. He refers to the
pre-Raph.xlite pictures representing allcgoricaliy the "Seven
Liberal .\rts,' and adds: "Dms une fresque ic'remment
dccouverte a Puy ... La Log'que tient en main un liizard ou
un scorpion. Dans un tableau d'Angelico elle lient diu.x
serpents qui se devorenl." 1 have not succeeded in finling any
further statement about ihis picture in the books on Art within
my reach, nevertheless this may prove an interesting addition
to the growing literature on cannibal snakes.

C. R. OsTKN Sacken.

Heidelberg, February 3.

3-14

NA TURE

February 7, 189;

PIERRE DUCHARTRE.

AS announced in our issue of November S, 1S94,
x.'ae. doyen oi French botanists died on the 5th of
that month, "having passed away without suffering, at
the advanced a^je of eighty-three " Pierre Duch.utre was
pre-eminently a practical botanist, whose teachings were
largely based upon actual knowledge, acquired by
observation and experiment. Almost before the found-
ation of the present German school of botanists, of
whom Sichi was one of the earliest exponents, Duchartre
published {1S67) the first edition of his well-known and
highly esteemed 'Elements de Botanique." It was the
result of thirty years' study and investigation ; his first
paper having appeared as early as 1S36. It is triie
that Sachs's " Handbuch der Experimental Physiologic
der Ptianzen" preceded it by one year; but for some
years Uuchartre's book held its own, not only in France
but also in this country. As we learn from a sketch of
his life by .Mr. Gaston Bonnier,' Duchartre commenced
his botanical studies under exceptionally ditiicult con-
ditions, even for that period ; but by great industry and
perseverance he soon gained for himself a name and
position which he maintained till the last. In 1S4.3 he
took up his abode in Paris, where he spent the last fifty
years of his lite, engaged in teaching, writing, and
original re-^earch. In 1S61 he replaced Payer at the
Academie des Sciences, and succeeded him in the
Botanical chair at the Sorbonne. For many years
Duchartre was one of the principal supporters of the
Socitfte Nationale d'Horticulture, and he was seven
times elected President of the Socieie Botanique de
France, of which he was one of the founders. He was
also President of the Socieie Nationale d'Agriculture,
and the Acaddmie des Sciences. Physiology and
organology, including teratology, were his principal
branches ot study ; but his very numerous contributions
to botanical and horticultural literature cover a much
wider field. Syste natic botany, however, received com-
paratively little attenti.)n from him ; a monograph of the
Aristolochiace^c being his chief work in this direction.
His last work was a summary, from the German, of
Engler's additions to Hehn's book on the native coun-
tries of cultivated plants. It appeared in the fournal of
the French Horticultural Society a month before his
death. H.

NOTES.

The rcmaios of the late Prof. Cayley were interred at
Ciiiibrid,;e on Kiiilay, and, notwiihstanciing the inclemency of
the wcai her, snow having fallen heavily during the night, the
proceedings were attended by a laryc number of persons. We
are indebied lo the Times for the following account of the
funeral : — The body was brought from Garden House at two
o'lI jck 10 Triiiiiy College, and was met at the great gale by a
piocessioD numbciing about 300 gentlemen, among them being
man/ notatile men of science. The pall bearers were the Vice-
Master of Triniiy (Mr. .\ldis Wiighl), Dr. Glalsher, the Right
Hon. George D<.'nman, Prof. Jebb, .M.P., Prof. Sir Kobcrt
Ball, Piof. J. J. Thomson, Lord Kelvin, and Prof. Sir G. G.
Stokes. The cboir headed the proceuion. Then came the officia-
ting clerg) — the Mister o( Tiinily, the Bishop of Durham, and the
Rev. K. St. John Pairy, senior dean. Fi.llowing the mourners
c«roe the l-ellows of Tiinily College — Mr. J. Prior, Dr. Jackson,
Mr. II. M. Taylor, Mr. B. E. Hammond, Dr. Kirkpat.ick, Dr.
Stanton, the Ktr. A. II. F. Bou,;hcy, Dr. Vcrrall, Mr. W. W.
R. Ball, Mr. R. D. Ilicki, Mr. R. T. GKiicbrook, Mr. F. J. H.
Jenkiosun, Dr. P.istgaie, .Mr. Fraser, Mr. J. G. Fraser, Mr.

' *■ L.« Vi* «t UCirrt^ e S<:ieolifi(|ue dc .M. Duchartre, " Revitt Cfniralt

J. D. Duff, Mr. A. N. \Vhitehe.nd, Dr. Sidgwir.k, Mr. J. N-
Langley, Mr. S. M. Le-ilhes, Rev. C. Plaits, Mr. C. Williams'
Mr. A. A. Bevan, Mr. G. T. Walker, Mr. W. C. \Vhelh.-im,
Mr. G. A. Davies, Mr. Capslick, .Mr. Innes, Mr. Nicholson,
Mr. Cowell, Mr. Moore, and .Mr. Wyse. Then came the Vice-
Chancellor of Ihe University and the representatives of the
German and United Slates Embassies — viz. H.S.H. Prince
Hermann von Schoenburg-Waldenburg for the German Ambas-
sador, and Mr. I). D. Wells on l)ehalf of the United States
Ambassador. Baron d'Estournelles de Constant had intended
to be present as representalive of the French Ambassador, but
was prevented at the last moment. The heads of Houses
included the Masters of Peterhouse, Clare, Caius, St.
C.itharine'.s, Jesus, Christ's, St. John's, Emmanuel, Sidney
Sussex, Downing, and Ayerst Hall, the President of t,;ueens', and
the Principal of Ridley Hall. The R lyal Society was represented
by Lord Rayleigh and Prof. .Michael Foster ; the Royal
Astronomical Society by Mr. Knobel ; the Mathematical
Society by Major MacMahon, Mr. Kempe, Prof. Elliott, and
Prof. Ilenrici ; the Cambridge Philosophical Society by Mr.
Larmor and Mr. Newall. The attendance likewise included
Profs. J. R. Lumby, H. B. Swete, E. C. Clark, A. Macalister,
T. M'kenny Hughes, \V. J. Lewis, H. E. Ryle, E. B. Cowell,
J. E. B. Mayor, J. .\. Ewing, W. W. Skeal, Sir G. M. Hum-
phrey, and C. S. Roy ; the Public Orator, the Registrary, Dr.
Routh, and many others. An impressive service was held in
the chapel of Trinity College. The concluding portion of the
service took place at the Mill Ro.id Cemetery, the Bishop of
Durham committing ihe body lo the grave.

We are glad to see that the Duke of Argyll has recovered
sufficienlly from bis illness lo remove from the residence of
Lord Kelvin lo Inverary Castle.

The very extensive and valuable botanical library of the
late Prof. N. Pringsheim has been presented to the German
Botanical Society, of which he was President, together with a
sum of 25,000 marks for ils maintenance.

The Berlin correspondent of the British Medical journal
reports that a gift of 1,500.000 marks (^75,000) has come lo
the German Royal .\cademy of Sciences from a widow lady,
Frau Wenzel. The sum is to remain as a foundation, and Ihe
interest used to assist scientific inquiries of importance.

The death is announced of Dr. Lombard, the author of a
standard work on Climatology from a medical point of view,
and in 1882 the President of the Inlcrn.itional Congress of
Ilygieueat Geneva. .\n eminent German engineer — Hermann
Gruson — h.as also just died, at M-igdeburg.

Reuter's correspondent at Chrisliania reports that earth-
quake shocks were felt at Chrisliansund, Molde, Aalesund, and
Bergen between 12.15 and "•43 "" '''^ morning of Tuesday,
February 5, cau ing windows to rattle and disturbing furniture.
The direction of the vibrations was from south-east to north-
west.

A DEfUTATlON from the recent Indian Medical Congress
has (says the Lancet) wailed upon Sir Anthony MacDonnell,
controlling Ihe Home Department, lo urge upon the Govern-
ment of India the extension of facilities for the study of pre-
ventive medicine and Ihe prosecution of scientific research in
that country. Sir .\nlhony MacDonnell, in his reply, assured
the deputation of his interest in the objects in view, and an-
nounced ihal, in addition to the bacteriological laboratory at
Agra, a similar institution for experimental research was to be
established at Lahore.

The United Slates Government hasesiablishcd an additional
wind signal, to be known as Ihe " llurric.ine Signal," to be
used in adJilion to the storm s goals previoudy shown. The

NO. 1319, VOL. 51]

Februarv 7, 1895]

NATURE

345

signal consists of two red flags with black centres, shown one
above the other, and will be used to announce the expected
approach of tropical hurricanes, and also of those extremely
severe and dangerous storuis which occasionally move across the
Lakes and the northern Atlantic shore. Whenever instructions
are received to show this signal at any station, every effort has to
be made to distribute the information, and all vessels have to be
notified that it is dangerous to leave port.

The Academy of Natural Sciences of Philadelphia, acting
on the report of the Committee on the Ilayden -Memorial
Geological Award, have voted the ilayden medal, and the
accumulated interest on ihe fund, to Prof. G- A. Daubrce. The
recipient in 1893 was Prof. Huxley. Prof. IJaubrce was born
in Melz, June 25, 1814, and is therefore now in his eighty-
second year. He graduated from the Kcole Polytechn.que in
1834, and immediately received a commission to assist in the
geological exploration of Algeria. He was called to the chair
of Geology in Strasbuig in 1839, and was Dean of its Scientific
Faculty in 1852. He was appointed Engineer-in-Chief in 1855.
In 1861, upon the death of the distinguished Cordier, he was
selected to replace him in the Museum of Natural History, and
as Professor of Mineralogy in the Ecole des Mines, as well as in
the Acadtmie dci Sciences in Paris. His writings have been
numerous, oiiginal, and important, and his researches into the
intricate causes of crystalline structure, and in the domain of
experimental geology, are of exceptional value.

By the death of Dr. F. Buchanan While, which took place
on December 3, 1894, at Perth, in his hfty-third year, Scotland
has lost one of her most active naturalists. His special
branches were entomology and botany. Dr. White was one of
the founders of the Perthshire Sjcitty of Natural Sciences, of
the Scottish Cryptogamic Society, and of the East of Scotland
Union of Naturalists' Societies ; and was the originator and
first editor of the Scottish Naturalist. He left, at the
time of his death, a nearly completed " Flora of Perth-
shire." The Entomologist's Monthly Magazine notes that his
friends are endeavouring to raise a fund to erect a memorial to
him. It is proposed to place a mural brass tablet in St.
Ninian's Cathedral, and also to procure an enlarged photograph,
to be hung in the lecture room of the Perthshire Society of Natural
Science. Any who wish to coniribute to this memorial may
send subscriptions to either Vincent L. Rorison, Dean of St.
Andrews, The Deanery, Perth ; or Henry Coates, President of

ithe Perthshire Society of Natural Science, Pitcullen House,
Perth.

Dr. Hermann Weber, a Fellow of the Royal College of
Phy.'^icians and .Surgeons, gave, last December, the sum of
;^25oo in truvt for the purpose of founding a prize to be called
the " Weber-I'arkes " prize, to be given at interv.ils for the best
essay on tubercular consumption. It has now been resolved
that the prize be awarded triennially to the writer of the best
essay upon some subject connected with the etiology, prevention,
pathology, or treatment, of tuberculosis, especially with
reference to pulmonary consumption in man ; ihat, in making
the award, the College have regard to careful collection of facts
and original research ; that the value of the prize be 1 50 guineas,
or such sum as the interest accrued on the capital, after payment
of expenses, will permit ; that a bronze medal be awarded to
the holder of the prize, and a similar medal, to be distinguished
\ as the " second medal," to the essayist who comts next in order
of merit. The competition will be open to members of the
medical profession in all countries, the essays lobe type-written,
and, if writlen in a foreign language, to be accompanied by a
translation in English. It is a condition of the competition
ihat each prize essay shall become the properly of Ihe College,
though the College may grant its author permission to publish it.
NO. I 3 19, VOL. 51]

On Friday last, a deputation from the British Medical
Association and the Ophthalmological Society waited upon Mr.
Bryce, President of the Board of Trade, to urge the adoption
of more precise tests for eyesight in the examination for the
mercantile marine and railway servants. Dr. Macnamara, in
introducing the deputation, said that railway and merchant
marine authorities did not insist upon proper precautions being
taken to exclude men with imperfect eyesight from being
employed as signalmen, and in the movement of trains and
vessels. Dr. Argyll Robertson held it was necessary that the
tests should be adequate and uniform, that they should be
skilfully employed, and that they should be applied at regubr
intervals. The tests should elicit three conditions: (1) the
acuteness of vision possessed by the applicant ; (2) the state of
refraction of the candidate's eye ; and (3) his acuteness of colour
perception. Mr. Bryce, in Ihe course of his reply, said he was
glad to gather from what had been said by members of the
deputation, that the tesis embodied in the Board's circular of
last September, to be applied to masters and males, were
recognised as being satisfactory, except in regard to the
question of refraction. He was perfectly certain, however, that
if the railway companie-.' examinations did not cover this
defect, they would soon take steps to apply ihe test for it. But
the Board of Trade had no statutory powers as regarded the
companies in this matter, neither had they any power to apply
the tests lo all persons entering the merchant service.

In June of last year, the Society for the Preservation of the
Monuments of Ancient Egypt discussed the importance of
having a thorough survey made of the Nile Valley from the
First to the Second Cataract —that is to say, of the district
which will be partially converted into a high reservoir when
the dam at -\ssouan, even in its reduced proportions, is con-
structed. A draft scheme for such an archaeological survey has
been drawn up by the Committee appointed to decide upon the
regions to be investigated and the work to be done. A list has
been compiled to show the most important antiquities along the
Nile Valley which require examination and copying. The
Committee propose that the survey should commence with a
preliminary reconnaissance, providing a general map and maps
of sites, to be followed by plans of ihe buildings and special
inquiries indicated in subsequent sections. It is probable that,
under the special circumstances of the case, if the maps and
plans referred to cannot be prepared for publication in Egypt,
application to the Board of .-Vgriculture might secure their
multiplication and reduction by the Ordnance Survey. Such a
course would secure perfect reproduction and a great economy.
It is proposed that illustrations, other than plans, should be
based on photographs, to be subsequently processed in printer's
ink. This would secure permanency and great economy, and
avoid all the expenses of hand illustration, which alone was
available in the expeditions of 1789 and 1844. The Committee
suggest that a non-commissioned officer of the Royal Engineers,
who has passed through the Photographic School at Chatham,
should be attached to one of the companies of Royal Engineers
stationed in Egypt, and be employed in obtaining the photo-
graphs. It is understood that the preliminary reconnaissance
is now about to commence, under the direction of the Public
Works, Irrigation, and Arch.'eological Departments of the
Egyptian Government, very much in accordance with the de-
tailed scheme, printed copies of which have been forwarded to
Egypt.

A PAPER on boiler explosions, read at the Institution of
Civil Engineers on January 29, by Mr. William H. Fowler,
presents some points of interest. The theories, such as
"deferred ebullition," "disassociation of water," "spheroidal
condition," which have been propounded to account for

346

.YA TURE

[February 7, 1895

such explosions, are well known. Mr. Fowler showed ihat
it was the ho: water, rather ihan the sleam, in the bjiler
which formed the source of destructive energy. In regard
to the causes of boiler explosions, there is nothing occult or
mysterious. They can, as a rile, bi traceil by pitieni investiga-
tion to ih: operation of simple an I well-known facts. Thus
when a boiler-shell is normally in a stae of high tension, if
once a rupture take-; place by the acti>n of sl.atic stresses on a
lotilly weak spot, the store 1-up ener.;y is capable not only of
tearing the boiler to pieces, but of producing all the other de-
structive effects ob-crvei in connection wiih such disasters.
Prou.inent among the principal causes of explosions is the
corrosion of the boiler-shell. Some explosions have iheir
origin in the stresses arising from expin-iion ani contrac-
tion due to the action of the fire. As an illustration of the
stresses set up by unequal expansion an 1 contraction in a boiler,
a case was mentioned in which an explosion occurred two hours
after the fires were drawn. A frequent sou'ce of boiler explo-
sions in the past is the practice of cutting large openings in
boiler-shells, wiihout providing compensating strengthening-
rings. Overheating from shortness of water is a common cause
of boiler explosions but the operation of thi> ouse is different
from the reason formerly assigned to it. Explosions are not
the result of turning c )Id water on to red-hot plates. What
takes place is that the overheated plates become gradjally
softened, with the result that they bulge downwards and are rent
at the ordmary working pressure : explosions of this kind are of
a relatively mild character. .Many explosions arise from ex-
cessive pressure in conseiuence of the defective action of the
3afely-v.ilve. This may o::cur in a variety of ways, but the type
of valve loaded with a spring-balance is the most prolific s nirce.
Fin.-illy, explosijns sometimes arise from faulty material and
construction. As a result of using iron of pojr quality with
punched holes, incipient H iws are occasionally set up in the
seams, and several cases have occurred in which these inherent
defects were so situated as In forbii detection when the boiler
was put togcth-r, and were only revealed by the explosion.
These defects show the value in connection with new work of a
carefal hydraulic test.

The barometer has been very high over north-west Europe
during the past week, and the type nf weather over these
islands has been anti-cyclonic, with strong ea-terly winds or
gales at several places on our coasts. In the nei^hbourhoril
of London the maximum day temperatures have not exceeded
35', and at ni);ht rhirp frosts have occurred. In the suburbs a
reading of 15° has b.en recorded, and a few miles distant the
lemptraiurc fell several degrees lower, with a radiation tem-
pcratuie of 6''5, while over the midland districts of England
the ihermometer in the shade has fallen 24° below the
freezing point. The Wctkly Wtathcr Ref.nt jiulilishcd by the
Meteorological Office states that during the week ending the
ind ins', the absolute sha-le minima recorded were— 2° at
Llandovfry on January 28, 1° at Hraemar on J.inuary 30, and
2' at llillington on January 27. Over the whole cmiiitiy the
temperature ranged froui 8' lo 13'bcli.w the mean for the week.
Snow has fallen at many places in different pans of the king-
<lum.

The beautiful Alpine phenomenon which the Swiss call
" Alpengluhen," is nola simple red ^low of the snowy peaks at
sunwl, but is sometime* intermittent, the glow returning once
or twice after it has apparently died away. Dr. J. Am>ler, in
a recent communication to the Swiss Natural Science Society,
eiplains Ih's repetition by takin*; into account the various
deviations undergone by the sun's rays in passing through the
rapidly cooling atmosphere. Since the air is colder in the higher,
and warmer in the lower strata, the solar rays undergo a kind
NO. 1319, VOL. 51]

of total reflection which makes them pass upwards again, so
that when the sun has reached a certain position they will no
longer strike ihi summits. This is llieendofthe first glow.
As the lower air cools, the rays become once more rectilinear,
and the second glow sets in. When the sun sinks still lower, its
rays are thrown down upon the L;laciers by ordinary refraction.
This refraction may be intensified by warm air from below
reaching the upper regions of the air, which would give rise to
the third glow. Kut the latter is only rarely observed.

It is gratifying to learn that the Italian Government has
appointed a commission to study the violent earthquake which
occurred in S)uih Italy on November 16. In the meantime,
Prof. Tacchini has established one result of great interest and,
possibly, of much practical importance (^. Accad. dei Lincei,
Rtnd. iii. 1S94, pp. 365-3')7). The earthquake was regis-
tered at Rome by three pendulums in the CoUegio Romano.
The matimum displacement occurred at jh. 55m. p.m.,
Greenwich mean time ; but the first movement was registered
by the great seismometrograph (length 1611., miss 200 kg.) at
5h. 5Zin. 25s., by another (length 6m., mass 100 kg.) at 5h.
52m. 30s., and by a third still less delicate (length l\n., mass
10 kg.) at 5h. 53m. 20s. Now a clock was stopped at
the observatory of Messina at 5h. 52m., there being no
slight shock previously, and the miximum disturbance
was registered at the same moment at the observatory
of Catania. It may be inferred, therefore, that before
the great shock took pl.ace, there w.as a microseismic
motion insensible to man and to ordinary apparatus. But, if
an instrument as delicate as that at Rome had been installed at
Messina, the beginning of the motion would have been recorded
2\ minutes before the occurrence of the sensible shock.

\Vk learn from the Journal of Botany, that a " Flora of
Berkshire," by Mr. Druce, will shortly be published.

The constant communication kept up by the central
authorities at Kew with the directors of the various colonial
botanic gardens, is bearing fruit in the numerous botanical
publications which proceed from the Colonies. We have on
our table the />«//i//« of MisceUancous Information from the
Royal 1! ilanic Garden, Trinidad, for January 1S95 ; the .^f^v-
cuUural Joninal of the Leeward Islands for October 1894;
and Notes on Antigua tnassts, by Mr. C. .V. IJarher, Superin-
tendent of .\griculture for the Leeward Islands ; all containing
notes .and information of value for the dwellers in the Tropics.

Five Biilletim of the University of Wisconsin have come
to us. One, the first of a Science Series, is on the speed of the
liberation of iodine in mixed solutions of potassium chlorate,
potassium iodide, and hydrochloric acid, the author thereof
being Mr. II. Schlundt. His experiments show that the speed
of the reaction increases lo a marked degicc with temperature.
The presence in the mixture of an excess of one or more of the
components also increases the speed, and an increase in the
degree of concentration acts in the same manner. The pre-
sence of hydrobromic acid accelerates the reaction ; and, to a
less extent, hydrochloric, nitric, and sulphuric acids. Organic
acids, however, and boric acid, do not increase the speed. The
four remaining flu/letins referred to belong to the Engineering
Series. In one, Mr. L. F. I.oree traces the devtiopmcnl of
railroads from 1S25 to the present time, chielly dealing with
the construction of the permanent way. Some practical hints
in dynamo design are given by Mr. Gilbert Wilkes in the
second of the series. The next, by Mr. C. T. I'urdy, refers to
the steel construction of buildings ; and the fouith, by Mr.
A. V. Abbott, deals with telephones and switchboards.

Two further communications concerning the new iodine
bases are contributed by pupils of Prof. Victor Meyer to the
current issue of the B/ri(hl,\ In the fir.st, Mr. John McCrae

February 7, 1895]

NA rUR£

347

describes the base and its salts derived from toluene, analogous
to the compounds previously described by Prof. Meyer and
Merr Hartmann derived from benzene. In the second memoir,
Mr. Wilkinson describes a further series derived from para-
chlor-iodo-benzenc, C,.HjClI. The formation of both series
occurs precisely as in the case of the benzene derivatives. The
base derived from toluene was prepared from the para iodide of
toluene asstarlingpoint. Its composition is(C|;H4. Clla)^! . OH,
iodine apparently acting, as in the bases previously described,
in a trivaient capacity, and forming the central element around
which the two toluene radicles and the hydroxyl are grouped.
The base itself has only been obtained in atjueous solution, but
many of the salts crystallise well, and are consequently readily
isolated. The iodide, {C|,Hj . CII^).,! . I, is precipitated as a
white powder, extremely sensitive to light, and melting at 146^
The corresponding chloride and bromide both crystallise from
water in needles which melt at almost the same temperature in
the neighbourhood of 178. The bichromate is a particularly
beautiful salt, crystallising from hot water iu large orange-red
plates. It is likewise explosive, detonating when heated. The
nitrate, (CgH, . CHj);! . NOj, is very soluble in water, and
melts at I39^ The per-iodide is a remarkable compound,
(C,;H4CH3)o( . r,, obtained by addition of two further .atoms of
iodine to the ordinary iodide above mentioned. It crystallises
in dark red needles, endowed with a very brilliant lustre, and
melting at 1 56 . In addition to these sails, double salts with the
chlorides of gold, platinum and mercury are described, all of
which crystallise well and exhibit definite melting points. The
base of the series described by Mr. Wilkinson possesses the
composition (C^HjCI).,! . OH, being deiived (rom para chlor-
iodo-benzene by reactions analogous to those by means of which
the base above described was obtained, and similar to those
previously described by Prof. Meyer. The iodide, chloride,
bromide, nitrate and chroniate, as well as double salts with the
chlorides of mercury and platinum, have been obtained in well-
defined crystals. Hence it would appear that the reactions
discovered by Prof. Meyer and Herr Hartmann, between
iodosoljenzene and silver oxide, and between sulphuric acid and
iodosobenzene, which resulted in the preparation of the first
iodonium bases, are of pretty general application in the benzene
series. These remarkable compounds containing iodine as the
grouping element must now, therefore, be regarded as
thoroughly well established, and the older idea as to the
nature of the iodine atom must give place to a fuller conception
of the capabilities of that element.

Th e additions to the Zoological Society's Gardens during the
past week include a Chacma Baboon {Cyiiocephahis portarius)
from South .Vfrica, presented by Captain Webster ; a White-
throated Capuchin {Celni; hypoUiiciis) from Ccniral America,
presented by Mr. H. W. Manning ; a Senegal Parrot (Puo-
cephahis sencgaltis) from West Africa, presented by Miss
.-Mice Firman.

OUR ASTRONOMICAL COLUMN.

New Stars and Ni;bul.i;. — The first number of the Aslro-
physical yoitriial has come to hand. It is [jractically a con-
tinuation ol .■Islionomy aiiJ Ashv J'ity.<i,i in a slightly dilferent
form, and i> now pu'iished by ihe Cliicago University Pie-s.
Among the contributions to the journal is a paper, by Prof. W.
W. Campbell, on some interesting and significant changes
which have occurred recently in the S|iccirum of Nova Auriga:.
The intensities of the two lines at K 4J60 and \ 5750 appear 10
have decreased very materially. When I'rof. Caiii|itiell observed
the Nova spectrum in 1S92, these two lines were stronjcr in
the Nova than in the nebul;\; in the spectra of which they were
seen and piiotographed. Observing last November, however,
he found that this condition of things was reversed, the lines

NO. I3IQ, VOL. 5 I

appearing relatively fainter in the Nova than in the nebulce. As-
is now very well known, the specira of nebula; differ both as-
regards the number and inlensiiy of the lines. The recent
obseivations of the Nova seem to show that the spectrum is not
only nebular, but it is approaching the average type of nebular
specirum. Prof. Campbell thus sums up the bearing of
spectroscopic observations upon theories proposed to account
lor the genesis of new stars: —

"The Harvard College Observatory has shown that both
Nova Aurigae and Nova Normse at discovery possessed sub-
stantially identical spectra of bright and dark lines, similarly
and equally displaced. Both diminished in brightness and botii
assumed tue nebular type of >pcctruiii. '1 he new star of 1876
in C)gnus probably had nearly an identical history : passing
from a bright star with a spectrum of bright and dark lii.es, to
a faint obj ct with a sptcirum consisting of one bright line
(undoul tcdly the nebular line A 5010, or the two nebu ar lines
A 5010 and A 4960 coml)ined). We may say that only five ' new
stars' have been discovered since the ap,ilication of the spectro-
scope to astionomital investigations, ant that tiiree of these
have had substantially identical speitroscopic histories. This
is a rtmaikable fact. We cannot say what the full significance
of this lai.t is. One result, however, is very clear : the special
theori.s proi ounded by various spettrostopists to account for
the phenomena observed in Nova AurigEe must unquestionably
give way to the mute gdiicial ihcoties."

The Designation of Comets. — A uniform system of
conietary notation is certainly needed. The Observalnry
poinis out that though the small letters a, b, c, &c.,a'e now
generally used to denote the order of discovery, and Roman
numerals 1., II., HI., &c., to indicate the order of perihelion
passage, astronomers are not agreed whether to write Comet ■;
1894, Brooks's Comet, or Comet Hrooks. It is therefore sug-
gested, and the suggestion deserves to be acted upon, that 111
the future the order shall be letter, year, Komiu numir^l, dis-
coverer. The lull name of the comet would then run as fol-
lows : — Comet a 1892, I. (Swill) : and if any part of the name
be quoted, this order should be preserved. Those who have
had to search for observation of comets in astronomical publica-
tions, will welcome the system of unifoimity in indexing, pro-
po-ed by our contemporary.

THE NEW CONSTITUENT OF THE
ATMOSPHERE.^

I. Densily of Nilrcgen from Various Sources.
In a former paper" it has been show that nitrogen extracted
from chemical compounds is about \ per cent, lighter than
** atmospheric nitrogen, '

The mean numbeis for the weights of gas contained in the
globe used were as follows : —

From nitric oxide 2'300I

From nitrous oxide 2 2990

From ammonium nitrite ... ... ... 2'2yii7

while for "atmospheric nitrogen" there was found —

By hot copper, 1S92 2'3loj

By hot iron, 1S93 23100

By ferrous hydrate, 1894 2 3102

At the suggestioH of Prof. Thorpe experimenls were subse-
quently tried wiih nitrogen liberated from Krea l)y ihe action of
sodium hypobromite. Tfie hypobromite was prepared from
commerciaf materials in the proportions recommended lor the
analysis ol urea. The reaction was well under control, and
the gas could be liberated as slowly as desired.

In the firat experiment thi gas was sulunitted to no other
treatment than slow passage through poiash and phosphoric
anhydride, but it soon became apparent that the nitrogen was
contaminated. The "inert ami inodorous" gas attacked
vigorously ihe mercury ol the Tupler pump, and was described
as smelling Tike a dead rat. As to the weight, it proved to be
in excess even of the weight of atmospheric nitrogen.

The corrosion ol the mercury and the evil smelf were in great

I Abstract of a paper by Lord Raytcigh, Sec. R.S., and Prof. William
Kaiiisay, F.K.b., read befure tile Koyai Suciely, .Tt a special mccung, on
Janu.iry 51.

- l<.iylcigh, *' On an Anomaly encountered in Determinations of the
Densily ol Niiiogen Gas," Kov. ^oc. Pivc. vol. Iv. p. 340, 1S94.

348

NA TURE

[February 7, 1895

degree obviated hy passing the gas over hot metals. For the
filliops of tune 6. 9, and 13 ihe ga* pas-ed ihroi'gh a ^ho^t
leag'h of I u^e containing coi>pei"in the lorm of fine "ire hraied
by a flat Bun'en burner, then through ihe fomace over red hot
iron, and batk over copper oxide. On Jure 19 the furnace
tubes were omitted, the gas being trealert with red hnt copper
only. The mean result, reduced so as to correspond with those
above quoted, is 2 29S5.

Without u.'.ing heat, it has not been found possible to prevent
the corrosion (■! the mercur)'. Kven whtn no una is employed,
and air simply bubbled through, the hypoliromiie siduiion is
allowed 10 pass with constant shaking over mercury contained
in a y lute, ihe surface of the meial «a«soon fouled.

Although the results relating to urea nilrogen are interesting
for compaii-on with that obtained from other nitrogen com-
pounds, the original object was not attained on account of the
necessiiy of reaming the treatment with hot me'als. \Ve have
found, however, ihit nitrogen from ammonium nitrite may be
prepared without the employment of hot tules whose wcijjht
agrees wiih that above quoted. It is true that the gas smells
slightly of ammonia, easily removable by sulphuric acid, and
apparently also of oxides of nitrogen. The mean lesull from
three fil ings is 2 29S7.

It will l)e seen that, in spite of the slight nitrous smell, there
is no appreciable difference in ihe densities of gas prepared
from ammonium nitrite with and without the treatment by hot
metals. The result is interesting as showing that the agree-
ment of numbers obtained for chemic.il nitrogen does not
depend upon the use of a red heat in the process of puri6ca-
tion.

The five results obtained in more or less distinct ways for
chemicil nitrogen stand thus : —

From nitric o»ide 2"300I

From nitrous oxide ... ... ... ... 2'2990

From am nonium nitrite purified at a red heat 22987
From urea ... ... ... ... ... 2 2985

From ammonium nitrite purified in the cold 2 2987

Mean ... ... ... 2*2990

These numbers, as well as those above quoted for "atmo-
spheric nitrogen, " are subject to a deduction o( o 0006 for the
shrinkage of the globe when exhaus'ed.' If they are then
multiplied in the ratio of 2 310S : I 2572, ihey will express the
weights of the gas in grams per litre. Thus, as regards Ihe
mean numbers, we find ts the weight per litre under standard
conditions of chemical nitrogen 1 '2505, that of atmospheiic
nitrogen being I 2572.

It i-. of interest to compare the density of nitrogen obtained
from chemical compoumis with that of oxygen. We have
N, : O, = 2*2984 : 26276 = o 87471 ; so that if 0„ = 16,
Mj = ■3'9954. Thus, when the comparison is with chemical
nitrogen, the ratio is very nearly that of 16 : 14 ; but if " atmo-
spheric nitrogen" be substituted, the ratio of small integers is
widely departed from.

To the above list may he added nitrogen prepared in yet an-
other manner, who«e weight has been determined sub-trqucnily
to the isolation of the new dense constituent of the atmosphere.
In this case nitrogen was actually extracted from air by means
of magnesium. The niirogen thus srparated was then con-
verted into ammonia by action of water up in the magnesium
nitride, ami aft'-rwards liberated in the free stale by means of
cilcrum hy|>ochlorilc. The purification was conducted in the
usual way, and included passige over red hot copper and copper
oxide. The following was the result : —

Globe empty, October 30, November 5 ... 2 823 13
Globe lull, October 31 o'Si395

Weight of gas . ... ... 229918

It difffrs inappreciably from the mean of other results, viz.
3°a990, and i> of special interest as relating to gas which at one
•tage of its history formed part of the atmosphere.

Another determination, with a different apparatus, of Ihe
density of "chemical" nitrogen from the same source, mag-
neiium nitride, which had been prepared by passing "atmo-
spheric" nitrogen over ignited magt.e^ium, may here be
recorded. The sample differed f'om that prcviowly mentioned,
inasmuch as it had not been subjected to treatment with red-

' Raylrigh, " On ihe Dcntitiei of the Principal Cuct," Roy. Soc. free.
%o). liti. p. Ill, rR)).

NO. I3I9, VOL. 51]

hot copper. After treating the nitride with water, the resulting
ammonia was distilled off, and collected in hydmchloric acid;
the solution was evaporated by dei.rc-es, the dry ammonium
chloride was dissolved in water, and its conon rated ."olutioB
added to a freshly- prepared solutim of so ium hypobiomite.
The nitr-'gen was collected in a gasholder over water which
had previou-ly been boilet, so as, at all events, partially to
expel air. The nitrogen passed into the vacuous gl .1 e through
a solution of potassium hydn xi ie, and through two dr\ing-
tubes, one containing soda-lime, and the otticr phosphoric
anhydride.

At 1838° C. and 754 '4 mm. pressure, 162 S43 c.c. of this
nitrogen weighed 0*18963 gram. Ilf-nce,

Weight of I litre at o" C and 760 mm. pressure = I •2521
gram.

'Ihe mean result of the weight of i li're of "chemical"
nitrogen has been found to equal I 2505. It is therefore
seen that "chemical" nitrogen, derived noin " atmospheric"
nitrogen, without any exposure to red hot copper, possesses the
usual densi y.

Experiments were also made, which had for their object to
prove that the ammonia produced (rom the magresium liitride
is identical with ordinary ammonia, and contains no other com-
pound of a basic character. For this purpose the ammonia
was converted into amminiiim chloride, and the percentage of
chl->rine determined by tiira'ion with a solution of silver nitrate
which had been standardised by limiting a specimen of pure
sublimed ammonium chloride. The silver solution was of such
a strength that I c.c. precipitated the cliloiine from 0001701
gram of ammonium chloride.

(1) Ammonium ch oride from orange-coloured .sample of
magnesium nitride contained 66 35 per cent, ot chlorine.

(2) Ammonium chloride from bl.icki»h magnesium nitride
contained 66 35 per cent, of chlorine.

(3) Ammonium chloride from nitride containing a large
amount of unaltackcd magnesium contained 66 '30 per cent, of
chlorine.

Taking for the atomic weii;hls of hidrogen II = i"oo32, of
nitrogen N = 1404, and of chlorine CI = 35 46, the theo-
retical amount of chlorine in ammonium chluiidc is66'27 per
cent.

From these results — !hat niirogen prepared from magnesium
nitride, obt.tined by passing "atmospheric" niirogen over ted-
hot magnesium has the density of "chemical " nitrogen, and
that ammonium chloride, prepared (rom magnesium nitride,
contains practically the same percentage of chlorine as pure
ammonium chloride — it may be c<mcluded that red-hot mag-
nesium with^lraws Irom "atmospheric nitrogen" no substance
other than nitrogen capable of forming a basic compound with
hydrogen.

II. Reasotis for susfeeting a hitherto Undiscovered Con-
stituent in Atr.

When the discrepancy of weights was first encountered,
attempts were naturally made to explain it by contamination
wiih known impurities. Of these the in 1st liki^ly appeared to be
hydrogen, present in the lighter cas in spite of the p.tssage over
red-hot cupric oxide. Hut inasmuch .is the intentional introduc-
tion of hydrogen into the hcivi r i;as, nfter>vatds treated in Ihe
same w.iy with cupric oxide, ha 1 no ■ ffect upon its weight, this
explanation had to be abandoned, and finally it became clear
that the dilT. rcncc could not be accounted lor by the presence
of anv known impurity. At this stage it seemed not improb-
able that the lightness of the gas extracted from chemical
compounds was to be explained by partial dissociation of
nirogrn molecules N. into detachcii atoms. In order to test
this suggestion both kimls of gas were submitleil to the action
of the silent electric discharge-, with the result that boih retained
their weights un.-iltered. This was discouraging, and a lurthcr
experiment pointed still more markedly in the negative direc-
lion. The chemical behaviour of nitrogen is such as to suggest
that ilissocialcd atoms would possess a high degree of .ictivity,
and that even though tliey might be formci in the first instance
their lilc would probably be short. On sianding iliey might be
exprc cil to ilisappear, in partial analogy wiih the known
liehivioiir of ozone. With this idea in view, a sample of
chemically prepared nitrogen was stored lor eight months. But
al the end of this time the dci.sity showed no sign of increase,
remaining exactly as at first.'

' Key. Stc. Prjc. vol. Iv., p. 344, iB<t4.

February 7, 1895]

NA TURE

549

Regarding it as estahlished that one or other of the gases
niu>t be a mixuire, containing, as I he ca^e m-ght he, an in^jre-
dient much heavier . r much lighter than oniinary n'trogen, we
had to cnnsidfr ihe relative proiiahiliiies of the vari .us possilile
inlerprelaiions. Except UDon the already discrediied h\po'.he<is
of dissociation, ii was difficult to see how the gas of chemical
origin could be a mixture. To suppose this would be to aimit
two kinds of ntric acifi, har<lly reconcilable wiih ihe work of
Slas and o'h'^rs upon the atomic weight of ihat subsrance. The
simplest explanation in many respects was to admit the exist-
ence of a yfcond ingreriient in air from which oxygeti, moisture,
and carbonic anhydride hid alrealy bee-n removed. The pro-
portional amount required was rol great. H the density of the
supposed gas were double that of nit'ogen ^ per cent, only by
volume would be needed ; or if the density were but half as
much agnin as that of ni:rogen, then I per cent, would still
suffice. But in accepting this explanation, even provisionally,
we had to face the improbabili'y [hat a gas surrounding us on all
sides, and present in enormous quandiies, could have remained
so long unsuspected.

The method of most universal application by which to test
whether a gas is pure or a mixture of components of different
densities is that of dillusion. liy this means Graham succeeded
in effecting a partial separation of the nitrogen and oxygen of
the air, in spite of the comparatively snia 1 difference of
densities. If the atmosphere contain nn unknown gas of any-
thing 1 ke the density supposed, it should be possible to prove
the fact by o|ieraiions conducted upon air which had undergone
atmolysis. This experiment, although in view from the first,
was not executed until a later stage of the inqu ry (§6), when
results were obtained sufi'ioient of themselves to prove that the
Atmosphere contains a previously unknown gas.

But although the method of diffusion was capable of decid-
ing the main, or at anv rate the first question, it held out no
prospect of isolating the new constituent of the atmo-|>here, and
we, therefore, turned our attention in the first instance to the
consideration of methods more strictly chemical. Aid here the
xjuestion fo'ced itself upon us as to what really was the evidence
in favour of the prevalent doctrine that the inert residue from
air after withdrawal of oxygen, water, and carbonic anhy-
dride, is all of one kind.

The identification of " phlocisticaled air" with the con-
stituent of nitric acid is due to Cavend sh, whose metlud con-
sisted in operating with electric sparks upon a short column of
gas confi' cd with pjtash over mercury at the upper end of an
inverted (J tube.'

Attempts to repeat Cavendish's experiments in Cavendish's
flianner have only increased the admiration with which we re-
gard this wondeiful investigation. Working on almost micro-
scopical quantities of mateiial, an^l by operations exienling
over days and weeks, he thus established one of the mo>t im-
portant facts in chemistry. And what is still more to the pur-
pose, he raises as distinctly as we could do, and to a certain
extent resolves, the question above suf^gested. The jiassageis
so important that it will be desirable to q'loie it at full length.

" As far as the experiments hitherto published extend, we
scarcely know more of the phlogisiicated part of our atmo-
sphere, than that it is not diminished by lime-water, caustic
alkalies, or nitrous air ; that it is unfit to support fire, or mnin-
tain life in animals ; and that its specific graviiy is not much
less than that of common air : so that though the nitrous acid,
by being united to phlogiston, is converted into air possessed
of these p operties, and consequently, though it was reasonable
to suppose, that part at least of the phlogi-licated air of the
atmosphere consists of this acid united to phlogiston, yet it was
fairly to be doubted whether the whole is of this kind, or
whether there are not in reality many different substances
compounded together by us under the name of phlogi-ticated
air. I therefore made an experiment to determine whether the
whole ofa given portion of the phlogisiicated air of the atmo-
sphere could be reduced to nitrous acid, or wh« th-r theie was
not a part ofa different nature to the rest, which would refuse
to undergo lhat change. The foregoing exi-ciment^ indeed
in some measure decided this point, as much the grtatesl part
of the air let up into the tube lost its elasticity ; yet as some
remained unabsorbcd, it did not appear for certain wheihenhit
was of the same nature as the rest or not. Fir this purpose I
diminished a similar mixture of dephlogisticated an. I common
air, in the same manner as before, till it was reduced to a small

I " ExperimcDts on Air," Phil. Trans, vol. I.xxv. p. 372,1785.

NO. I319, VOL. 51]

part of its original hulk. I then, in order to decompound as

much as I could of the phlogisticated air which remained in the
lube, add. d some dephlogisticated air to i', and continued the
spark until no further diminution took place. Having by
these means condensed as much as I could of ihe phlogisiicated
air, 1 let up some solution of liver of sulphur to absorb the
dephlogisticated air : after which only a small lmt>ble of air
remained unabsorbed, which certainly was not more tn^n iljof
the bulk of the phlogisiicated air let up into the tube ; so itiat
if there is any part of ihe phlogisticated air of our atmo-phere
which differs from the rest, an I cannot be reduced to nitrous
acid, we may safely conclude lhat it is not more than il^th
part of the whole."

Although Cavendish was satisfied with his result, and does
not decide whether the small residue was genuine, our ex-
periments about to be related render it not improbable that
his residue was really of a different kind from the main bulk of
the " phlogisticated air, " and contained the gas now called
argon.

Cavendish gives data' from which it is possible to determine
the rate of ab_-.orption of the mixed gases in his experiment.
This was about I c.c. per hour, of which two-fifths would be
nitrogen.

III. Methods of Causing Ficc Nitrogen to Combine.

To eliminate nitrogen from air, in order to ascertain whether
any other gas could be detected, involves the use of some ab-
sorbent. Theelementswhich have been found to combine directly
with nitrOiien are: boron, silicon, titanium, lithium, strontium,
barium, magnesium, aluminium, mercury, and, under the
influence of an electric discharge, hydrogen in presence of acid,
and oxygen in presence of alkali Besides these, a mixture of
barium carbonate and carbon at a high temperature is known to
be tflfective. Of those tried, magnesium in the lorm of turnings
was found to le the best. When nitrogen is passed over
magnesium, heated in a tube of hard glass to bright redness,
combustion with incandescence begins at the end of the tube
through which the gas is introduced, and proceeds regularly
until all the metal has been converted into nitride. Between
7 and 8 litres of nitrogen can be absorbed in a single tube;
the nitride formed is a porous, dirty orange-coloured substance.

XV. Early E.\-periments on Spariing JVitrogen with Oxygen
in preseitce of Alkali.

In our earliest attempts to isolate the suspected gas by the
method of Cavendish, we used a RuhmkortV coil of medium
size aciuated by a battery of five Grove cells. The gases were
contained in a test-tube standing over a large quantity of weak
alkali, and the current was conveyed in wires insul ited by
(J-shaped glass tubes passing through the liquid round the
mouth of the test-tube. With the given battery and coil a
somewhat short spark or arc of about 5 mm. was found to be
more lavourat)le than a longer one. When the mixed gases
were in the right propoiliim the rate of absorption was about
30 c.c. per hour, or thirty times as last as Cavendish could work
with the electrical machine of his day.

To lake an example, one experiment of this kind starled with
50 c.c. of air. To this oxygen was gradually added, until oxygen
being in excess, there was no perceptible contraction during an
hour's sparking. The remaining gas was then transferred at
the pneumatic trough to a small measuring vessel, sealed by
mercury, in which the volume was found to be 10 c.c. On
treatment with alkaline pyrogallate, the gas shrank to o 32 c.c.
That this small residue could not be nitrogen was argued from
the fact that it had withstood the prolonged action of ihe spark,
although mixed with oxygen in nearly the most favourable
prof>oition.

The residue was then transferred to the test-lube with an
addition of another 50 c.c. of air, and the whole worked up
with oxygen as before. The residue was now 2'2 c.c, and,
after removal of oxygen, 076 c.c.

Although it seemed almost impossible lhat these residues
could be either nitrogen or h\drogen, some anxiety was not un-
natural, seeing thai the final spaiking took place under some-
what abnormal conditions. The space was voty resiricltd, and
the temperature (and with it the proportion of aqueous vapour)
w.as unduly high. But any doubts lhat were fell upon this
score were removed by comparison experiments in which the
whole quantity of air operated on was very small. Thus, when

' Phil. Tretfts. x'fl. Ixxviii. p. 271, 1788.

350

NA TURE

[February 7, 1895

a mix'ure of 5 cc. of air with 7 c.c. of oxygfn was sparked for
Ij hours, ihe residue was o"47 c.c, and ader removal of oxygen
oxj6 c.c Several rcpetiiiiins having given similar result*, it
became clear that the final residue did not depend upon any-
thing that might happen when sparks passed through a greatly
reduced volume, /■«/ ■aias in {rofortion to the amount oj air
operat.J upon.

No satisfactory examination of the residue which refused to
be oxidised could he made without the accumulation of a larger
quantity. This, however, was difficult of attainment at the time
in question. It was thought that the cause probahly lay in the
solubility of the gas in water, a suspicion since confirmed. At
leng'h, however, a sufficiency was cllecled to allow of spark-
ing in a specially constructed tu'-e, when a comparison with the
air spectium, taken under similar conditions, proved that, at
any rate, the gas was not nitrogen. .\t first scarcely a trace of
the principal nitrogen lines could be seen, but after standing
over water for an hour or two these lines became apparent.

V. Early Expiiments on ll'it/idrawal of Nitrogen front Air ly
means of RcJIiot Afagnoiiim.
A preliminary experiment carried out by Mr. Percy Williams
on the absorption of atmospheric nitrogen, freed from oxygen
by means of red-hot copper, in which the gas was not passed
over, but simpiv allowed to remain in contact with the metal.
gave a residue of density I4"88. This result, although not con-
clusive, was encouraging ; and an attempt was made, on a
larger scale, by passing atmospheric nitrogen backwards and
forwards over redho! magnesium from one large gas-holder
to another to obtain a consideraKle quantiiy of the hcnvier gas.
In the course of ten days, about 1500 c.c. were collected and
transferred gradually to a mercury gas-holder, from which the
gas was passed over soda lime, phosphoric anhydride, mag-
nesium at a red-heat, copper oxide, soda-lime, and phosphoric
anhydride into a second mrrcury gas-holder. After some days
the gas was reduced in volume to ahoui 200 c.c, and iis density
was found to be l6-|. After further absorption, in which the
volume uas still further reduced, the density of the residue was
increased to iQ'og.

On passing sparks for several hours through a mixture of a
small quantity of this gas with oxygen, its volume was still
further reduced. Assuming that this reduction w.is due to the
further elimination of nitrogen, the density of the remaining
gas was calculated to be 200.

The spectrum of the gas of density 1909, though showing
nitrogen bands, showed many othrr lines wbich were not recog-
■isable as belonging to any known element.

VI. Proof of the Presence of Argon in Air by means of
Atmolysis.

It has already (§ II.) been suggested that if "atmospheric
nitrogen" contains two gases of different densities, it should
lie possible to obtain direct evidence of the fact by the
method of atmolysis. The present section contains an account
of carefully conducted experimen's directed to this end.

The atmilyser was prepared (after (Jrnham by combining a
number of "churchwarden" tobacco pipes. At first twelve
pipes were used in three group', each group including four
pipes conneced iu scries. The three groups were then con-
nected in parallel, and placed in a large glass tube closed in
such a way that a partial vacuum could be maintained in Ihe
space outside the pipes by a water pump. One end of the
combination of pipes was open to the atmosphere ; the other
end was connected to a boitle aspirator, initially full of water,
and so arranged as to draw about 2 per cent, of the air which
entered the other end of the pipes. The gas collected was
thus a vety small proponiun of ihal which leaked through the
pores of the pipes, and should be ri-laiively rich in the heavier
constituents of the atmosphere. The flow of water from the
aspirator could not be maiiaiined very constant, but the rate of
2 per cent, was never much exceeded.

The air thu« obtained was treated exactly as ordinary air had
been trealeil in determinations of the density of atmospheric
nitrogen. 0<)gen was removed by red hot copper, followed
by cupric oxide, ammonia by sulphuric .icid, moisture and car-
bonic acid by po'aih and phosphoric anhydride.

In a total weight of approximately 23 grams the excess of
weight of the diffused nitrogen over oniina'y atmospheric nilro-
jjen was in four experimei t<, 00049. 00014, 00027, 00015.

The mean exce»s of the lour dcicrminations is 0'00262 gram,

NO. 1319, VOL. 51]

I
or, if we omit the first, which depended upon a vacuum weighs
ing of two months old, 0001S7 gram.

The gas from prepared air was thus in every case denser than
from unprepared air, and to an extent much beyond the possible
errors of experiment. The excess was, however, less th.in had
been expected, and it was thought that the arrangement of the
pipes could he improved. The final delivery of gas fiom each
o.' the gioups in larallel being so small in compaiison with the
whole streams concerned, it seemed possible that each group
was not contributing its proper share, and even ihat there might
be a flow in the wrong direction at the delivery end of one or
two of them. To meet this objection, the arrangement in
parallel had to be abandoned, and for the remaining experi-
ments eight pipes were connected in simple series. The porous
surface in operation was thus reduced, but this was p.irtly com-
pensated for by an improved vacuum. Two experiments were
made under the new conditions, in which the excess was
I., 00037 ; II., o'oo33.

The excess being larger than before is doubtless due to the-
greattr efficiency of the atmolysing apparatus. It should be
mentioned that the above recorded experiments include all that
have been tried, and the conclusion seems inevii.ible that
"atmospheric nitrogen" is a mixture, and not a simple body.

It was hoped that the concentration of the heaviei constituent
would be sufficient to facilitate its preparation in a pure state by
the use of prepared air in substitution for ordiimy air in the
oxygen apparatus. The advance of 3! milligrams on the II
milligrams, by which atmospheric niirogen is heavier than
chemical nitrogen, is indeed not to be despised, and the use of
prepared air would be convenient if the diffusiim apparatus
could be set up on a large scale and bs made thoroughly self-
acting.

VII. Negative Experiments to firoTe t/'ial Argon is not JeriveiC
from Nitrogen from Chemical Sources.

.\Ithough the evidence of the existence of argon in the atmo-
sphere, deiived from ihe comparison of densities of atmospheric
and chimical nitrogen and from the ditTusion experiments
(§ VI.), appeared ovcr» helming, we have thought it undesirable
to shrink from any labour that would tend to complete the
verification. Wiih this object in view, an experiment was
undertaken and carried to a Conclusion on N'ovemher 13, in
which 3 litres of chemical nitrogen, prepared from ammonium
nitrite, were treated wiih oxygen in precisely the manner in
which atmospheric nitrogen had been found to yiclil a residue
of argon. The gas remaining at the close of the large scale
opeiations was worked up as usual with batteiy and coil until
the spectrum showed only slight traces of the niirogen lines.
When cold, the residue measured 4 c.c. This was transferred,
and after treatment with alkaline pyrogallalc to remove oxygen,
measured 33 c c. If atmospheric nitrogen had been employed,
the final residue should have been about 30 c.c. Of the 3'3c.c.
.ictually left, a part is account! d lir by an acciileni, and the
result of the cxpcrimi nt is to show that argon is not formed by
sparking a mixture of oxygen and chemical niirogen.

In a second ixpenmini of thesamc kind 5660 c.c. of nitrogen
from ammonium nitrite was treated with ox)gcn. The final
residue was 35 c.c. and was found to consist mainly of argon.

The source of the residual aigon i^ to be sought in the water
used for the manipulation of the large quantities of gas (1 litres
of nitrogen and II litresof oxygen) employed. When carbonic
acid was collected in a similar manner and subsequently ab-
sorhuil by potash, it was fiund to have acquired n contaiuinalion
consistent with this explanation.

Negative experiments were also carried out, absorbing nitro-
gen by means o( magnesium. In one instance 3 litres of nitrogen
prepared from ammonium chloride an<l bleaching-powder was
reduced in volume to 45 c. c , and on sjiarking with oxygen its
volume was further reduced to about 3 c.c. The residue ap-
peared lo consist of argon. Another cxpctimmt, in which 15
litres of nitrogen from ammonium nitiite was absorbed, gave a
final residue o( 35 c.c. Atmospheric nitrogen, in the latter
ca.se, would have yirlded 150 c.c, hence less than ^„\\\ of the
noimal ({uantity was obtained. It should be mentioned that
leakage occurred at <ine stage, by which perhaps 200 c.c of air
entered the apparatus ; and liesides, the nitrogen was collected
over water from which it tloublless acquired .some argon,
tjuantitative negative experiments of this nauiie are exceedingly
diflicull, and require a long lime to cany them 10 a successful
conclusion.

I

February 7, 1895]

NA TURE

351

VIII. Separation of Ar^on on a Large Scale.

To prepare argon or. a large scale, air is freed from osygen
■by means of red-hot copper. The residue is then pased from
a gas-holder through a combuslion tube, heated in a furnace,
and containing copper, in order to rem ive all traces of oxyjjen ;
the issuing gas is then dried by passage over soda-lime and
phosphorus pentoxide, after passage through a small (J lube
containing sulphuric acid, to indicate the rate of How. li then
«Dters a combustion-tube packed tighily with magnesium turn-
ings, and healed to redness in a >econd furnace. P'rom this
tube it passes through a sec(»nd index tube, and enters a small
gas-holder capable of containing 3 or 4 litres. A single tube
of magnesium will absorb from 7 to 8 litres of nitrogen. The
temperalure must be nearly that of the fusion of the glass, and
the current of gas must be carefully regulated, else the heat
developed by the union of the magnesium with nitrogen will
fuse the tube.

Having collected the residue from 100 or 150 litres of
atmospheric nitrou'en, which may amount to 4 or 5 litres, it is
transferred to a small gas-holder connected wiih an ajjparatus,
wherel-y, by means of a species of a self-acting Sprengel's pump,
the gas is caused to circulate through a tube half filled with
copper and half with copper oxide ; it then traverses a tube
ilalf filled with soda lime and half with phosphorus pentoxide ;
it then passes a reservoir of aboui 300 c.c. capacity, from which,
by raising a mercury reservoir, it can be expelled into a small
gas-holder. Next it passes through a lube containing mag-
nesium turnings heated to bright redness. The gas is thus
freed from any possible contamination with oxygen, hydrogen,
or hydrocarbons, and nitrogen is gradually absorbed. As the
amount of gas in the tubes and reservoir diminishes in volume,
it draws supplies from the gas-holder, and finally, the circulat-
ing system is full of argon in a pure state. The circulating
system ol tubes is connecied with a mercury pump, so that, in
changing the magnesium tube, no gas may be lost. Before
ceasing to heat the magnesium tube the system is pumped
empty, and the collected gas is restored to the gas-holder ;
finally, all the argon is transferred from the mercury reservoir
to the second small gas-holder, which should preferably be filled
with water saturated with argon, so as to prevent contamination
from oxygen or nitrogen ; or, if preferred, a mercury gas-holder
may be employed. The complete removal of nitrogen from
argon is very slow towards the end, but circulation for a couple
of days usually effecis it.

The principal objection to the oxygen method of isolating
argon, as hitherto descri'ied, is the extreme slowness of the
operation. In cxtenHing the scale we had the great advantage
of the .advice ol Mr. Crookes, who not long since called .ntten-
tion to the flame rising from platinum terminals, which convey
a high tension alterna'ing electric discharge, and pointed cut its
dependence upon combustion of the nitrogen and oxygen of the
air.' The plant consists of a De Mcritens alternator, actuated
by a gas engine, and the currents ate transformed to a high
potential by means of a RuhmkorlT or other suitable indue ion
coil. The highest rate of absorption of the mixed gasc; yet
attained is 3 litres per hour, about 3CCK) times that of Caven-
dish. It is necessary to keep the ajiparatus cool, and from this
and other causes a good many difficulties have been en-
countered.

In one experiment of this kind, the total air led in after
seven days' working, amounted to 7925 c.c, and of oxygen
{prepared from chlorate of potash), 9137 c.c. On the eighth
and ninth days oxygen alone was added, of which about
500 c.c. was consumed, while there remained about 700 c.c. in
the flask. Hence the proportion in which the air and oxygen
combined was as 79 : go. The progress of the removal of the
nitrogen was examined from time to time with the spectro-
scope, and became ultimately very slow. .Vt last the yellow
line disappeared, the contraction having apparently stopped for
two hours. It is worthy of notice that, with ihe removal of the
nitrogen, the arc discharge changes '.greatly in appearance,
becoming narrower and blue rather than greenish in colour.

The final treatment of the le idual 700 c.c. of uas was on the
model of the small scale operations already described. Oxygen
or hydrogen could be .supplied at pleasure from an electrolytic
apparatus, hut in no way could the volume be reduced below
65 c.c. This re idue refused oxidation, and showed no trace
of the yellow line of nitrogen, even under favourable condi-
tions.

' Clicmtcal Xc-vs^ vol. Iw. p. 301, iSjr.

When the gas stood for some days over water, the nitrogen
line reasserted itself in the speclmm, and many hours' sparking
with a little oxj'gen was rei|uired again to get rid of it. Inten-
tional additions of air to gas free from nitrogen showed that
about li percent, was clearly, and about 3 percent, was con-
spicuously, visible. About the same numb rs apply to the
visibility of nitrogen in oxygen when sparked under these
conditions, that is, at atmospheric pressure, and with a jar
connected to the secondary terminals.

IX. Density of Argon prepared by means of Oxygen.

A first estimate of the density of argon prepared by the
oxygen method was founded upon the data already recorded
respecting the volume present in air, on the assumption that
the accurately known densities of atmospheric and of chemical
nitrogen differ on account of the presence of argon in the former,
and ihat during the treatment with oxygen nothing is oxidised
except nitrogen. Thus, if

D = density of chemical nitrogen.
D' = ,, atmospheric nitrogen,

tl = „ argon,

a = proportional volume of argon in atmospheric
nitrogen,

the law of mixtures give

ar/-f (I- a)D = r)',
or d=D~{D'-D)/a.

In this formula D' - D and a are both small, but they are
known with fair accuracy. From the data already given

079 -7925

whence if (on an arbitrary scale of reckoning) D = 2'2990,
D' = 23i02, we find </=3'378. Thus if N^ be 14, or O; be 16,
the density of argon is 20'6.

-\ direct determination by weighing is desirable, but hitherto
it has not been feasible to collect by this means sufficient to
fill the large globe employed for other gases. .\ mixture of
about 400 c.c. of argon with pure oxygen, however, gave the
weight 27315, o'l045 in excess of the weight of oxygen, viz.
20270. Thus, if a he the ratio of the volume of argon to the
whole volume, the number for argon will be

2'627o - O'i045/o.

The value of a, being involved only in the excess of weight
above that of oxygen, doss not require to be known very ac-
curately. .Sufficiently concordant analyses by two methods gave
a — o'i845 ; whence for the weight of the gas we g^t 3 193, so
that, if O., = 16, the density ol the gas would be I9'45. ^^
allowance for re-idual nitrogen, still visible in the gas before
admixture of oxjgen, raises this number to 197, which may bs
t.aken as the density of pure argon resulting from this deter-
mination.

X. Ilensity of .Argon prepared by means of .Magnesium.

The density of the original sample of argon prepared has
already been mentioned. It was 1909 ; and, afier sparking
with oxygen, it was calculated to be 200. The most reliable
results of a number of determinations give it as I9'90. The
difficulty in accurately determining the density is to make sure
that all nitrogen has been removed. The sample of density
1990 showed no spectrum of nitrogen when examined in a
vacuum tube. It is right, however, to remark that the highest
density registered was 20'3S. But there is some reason here to
distruit the weighing ot the vacuous globe.

XI. Spectrum of Argon.

The spectrum of argon, seen in a vacuum tube of about
3 mm. pressure, consists of a great number of lines, dislributed
over almost the whole visible field. Two lines are specially
characteristic ; they are less refrangible than the red lines of
hydrogen or lithium, and serve well to identify the gas, when
examined in this w.ay. Mr. Crookes, who will give a full ac-
count of the spectrum in a separate communicatiim, has kindly
furnished us with Ihe accurate wave-lengths of these line-', as
well as of some others next 10 be described ; they are respec-
tively 696 56 and 70s '64, 10 ■'■ mm.

licsides these red lines, a bright yellow line, more refrangible
than the sodium line, occurs at 603 S4. .\ group of five bright

NO. I319, VOL. 51]

352

NATURE

[February 7, 1895'

green lines occurs orxt, besides a number of less intensity. Of
the group of five, the second, which is perhaps the most bril-
liant, has the wave-length 56100. There is next a blue or
blue violet line of wave-length 4702 ; and last, in the less easily
visible part of the spectrum, there are five strong violet lines, of
which the fourth, which is the most brilliant, has the wave-
length of 420'0.

Unfortunately, the red lines, which are not to be mistaken
for those of any othtr suhstancc, are not easily seen when a
jar discharge is passed through argon at atmospheric pressure.
The spectrum seen under these -conditions has been examined
by Prof. SchuNier. The most characteristic lines are perhaps
those in the neighbourhood of 1-", and are very easily seen if
there be not too much nitrogen, in spite of the presence of
some oxygen and water vapour. The approximate wave-
lengths are —

blrong.

F.

Not quite so strong.

Strong.

Fairly strong charac-
teristic triplet.

4S7 91
[48607]...

4S4 7> -
480 52 ..
476-50 ...

473 5^ -
472 56 ...

It is necessary to anticipate Mr. Crookes' communication,
and to stale that when the current is passed from the induction
coil in one direction, that end of the capillary tube next the
positive pole appears of a redder, and that next the negative
pole of a bluer hue. There are, in effect, two spectra, which
Mr. Crookes h.is succeeded in separating to a considerable
extent. Mr. E. C. Baly, who has noticed a similar
phenomenon,' attributes it to the presence of two ga.ses. The
conclu-inn would fdUow that what we have termed "argon"
is in reality a mix'ure of two gases which have as yet not been
separated. This conclusion, if true, is of great importance, and
experiments are now in progress to test it by the use of other
physical methods. Ihe full bearing of this possibility will
appear latrr.

The presence of a small quantity of nitrogen interferes
greatly wi'h the argon spectrum. But we have found that in a
tube «ih platinum ekclrodcs, after the discharge has been
passed fir f lur hours, the spectrum of ni'rogen disappears, and
the argon spectrum manifests ilself in full purity. A specially
constructed tube wiih magnesium electrodes, which we hoped
would yield good results, removed all traces of nitrogen, it is
true; but hydrogen was evolved from the magnesium, and
showed its characierisiic bnes very strongly. However, these
are easily identified The gas evolved on heating magnesium
in vacuo, as proved by a separate experiment, consists entirely
of hydrogen.

Mr. Cro'ikes has proved Ihe identity of the chief lines of the
spectrum of gas separated from air-nilrogen by aid of magnesium
with that remaii'ing after sparking the air-nitrogen with oxygen
in presence of caustic soda solution.

I'rof. .Schust r also has found the principal lines identical in
the spectra of the two gases, as observed by the jar discharge
at atmospheric pressure.

XII. Solubility of Argon in H'a'.cr.

Uelerminaiions of the solubility in water of argon, prepared
by sparking, gave 3 94 volumes per too of water at 12'. The
solubility of gi« prepared by means of magnesium was found to
be 4*05 vidumes per 100 at ijg". The gas is therefore about
2^ liiuct as solul>le as iiiiri>gcn, and possesses approximately
(be same s>ilu>>ility as oxygen.

The fact that argon is more soluble than nitrogen would lead
us to expect it in increa-ed proportion in the dissolved gases of
rain naier, Experiment ha< confirmed this anticipation.
"Nitiogrn" prepircd frrim the dissolved gases of water
supplied fiom a r.iin-water cislern w.is wei^^hed upon two
occasions. The wci,;hi«, corresponding to those recorded in
( I- , were 2'322I and 2 3227, showing an excess of 24 milligrams
above the weight of t>ue nitrogen. .Since ihe corresponding
excess (or " atmospheric nitrogen " is 11 inilligiam<, we con-
clude thai ihc water " nitrogen " is relatively more than twice
as rich in argon.

On the other band, gas evolved from Ihe hot spring at Bath,

• rri>i. f'liyt S»c-, i8>3, p. 147. He Myt :— " When an electric current
tk pa«««d thr u4^ ■ •i4iiiire of iwotaMff, one it tc|mratcd from itic other
and a^pcariin ilie negative hIow."

NO. 1319. VOL. 51]

and collected for us by Dr. A. Richardson, gave a residue afler
removal of oxygen and carbonic acid, whose weight was only
about midway between that of true and atmospheric nitrogen.

XIII. Behaviour at Loiv Temperatures.^

Prelimin.ary experiments, carried out to liquefy argon at a
pressure of about too atmospheres, and at a temperature of
— 90', failed. No appearance of liquefaction could be observed.

Prof. Charles Olszewski, of Cracow, the well-known authority
on the constants of liquefied gases at low temperatures, kindly
offered to make experiments on the liquefaction of argon. His
results are embodied in a sepitaie cominunication, but it is
allowable to stale here that the gas has a lower critical tempera-
lure ( - 121°) and a lower boilirg point t - 187°) than oxygen,
and that he has succeeded in solidifying argon to white crystals,
melting at -l89'6". The density of the liquid is approxi-
mately 1*5, that of oxygen being 1124, and of nitrogen 0SS5.
The sample of gas he experimented with was exceptionally
pure, and had been prepared by help of magnesium. It showed
no tiace of nitrogen when examined in a vacuum tube.

XIV. Ratio of Specific Heats.

In order to decide regarding the elementary or compound
nature of argon, experiments were made on the velocity of
sound in it. It will be lemeuibered that, from the velocity of
sound in a gas, the latio of specific he.it at constant pressure to
that at constant volume can be deduced by me.ius of the
equation

when « is the frequency, .\ the wavelength of sound, v its
velocity, e the isothermal ol.isticily, li the density, (i -k- at) the
temperature correction, C,, the specific heal at constant pres-
sure, and C, that at constant volume. In comp.aring two gases
at the same temperatuie, each of which obeys Boyle's law with
sufficient approximation, and in using the same sound, many of
these ttrms disappear, and the ratio of specific heats of one gas
may be deduced from that of the other, if known, by means of
the proportion

K-d : K''-d' :: I 41 : x,

where, for example, A. and d refer to air, <.f which the ratio is
l'4i, according to observations by Riintgen, WUIlner, Kayser,
and Jamin and Richard.

Two completely different series of observations, one in a tube
of about 2 mm. diameter, and one in one of 8 mm., made with
entirely dilTerent samples of gas, gave, the first, I 65 as the
ratio, and, the second, I 61.

Experiments made with the first tube, to test the accuracy of
its working, gave for caibon dioxide the ratio 1276, instead of
I '288, the mean of all jirevious deter inin.ations ; and the half
wave-length of sound in hydrogen w-ts fouml to be 736,
insiead of 74 5, the mean of those previously found. The ratio
of the specific heats of hydrogen found was i ' j9, instead of
I -402.

There can be no doubt, therefore, that argon gives practi-

cal'y the ratio of specific heats, viz. i 66, proper to a gas in

which all the energy is translalional. The only other gas

which has been found to behave similarly is mercury gas, at a

I high temperature.

' -W. .Atlcmfts to induce Chemical Ccmliiiuition.

Many atlcmpls to induce argon to combine will be described
in fiill in ihe complete paper. Suffice it to say here, that all-
suih attempts have as yet proved abortive. Argon does not
combine with oxygen in presence of alkali under the influence
of the electric di^chargc, nor with hydrogen in picseiice of aciti
or alkali also when sparked ; nor with chlorine, diy or moist,
when sparked ; nor with phosphorus at a bright-red heat, nor
with sulphur at bright redness. Tellurium maybe distilled ip
a current of the gas; so may sodium and ]o:assium, their
metallic lustre remaining unchanged. It is unabsorbed
by passing it over fused red hot caustic soda, or sidn-lime
healed to bright redness ; it passes unaffected over fused and
bright icd-hot potassium nilrale; and red-hot sodium peroxide
does not combine with it. Persulphidcs of sodium and calcium

1 The arraneemcnts for the expnimcnts upon ihis branch of the subject
were left cnlircty in ('rof. Rams y\ hnnds.

' Kundland Warburg, l'«es I"", vol. cxxxv, pp. Jj; and 507.

February 7, 1895 J

NA TURE

JJO

are also without action at a red heat. Platinum black does
not absorb it, nor does platinum sponge, and wet oxidising
and chlorinating agents, such as nitrohydrochloric acid, bro-
mine water, bromine and alkali, and hydrochloric acid and
potassium permanganate, are entirely without action. Kxpcri-
ments with (luorine are in contemplation, but the difficulty is
great ; and an attempt will be nude to produce a carbon arc
in the gas. Mixtures of sodium and silica and of sodium and
boracic anhydride are also without action, hence it appears to
resist attack by nascent silicon and by nascent boron.

XVI. (ktieral Coiicltntoiis.

It remains, finally, to discuss the probable nature of the gas,
or mixture of gKC'!, which we have succeeded in separating
from atmospheric air, and which we provisionally name argon.

The presence of argon in the atmosphere is proved by many
lines of evidence. The high density of "atmospheric nitro-
gen," the lower density of nitrogen from ihemical source-, and
the uniformiiy in the density of samples of chemical nitrogen
prepared from difterent compounds, lead to the conclusion that
the cause of the anomaly is the presence of a heavy gas in air.
If that gas possess the density 20 compared with hydrogen,
"atmospheric" nitrogen should contain of it approximately i
per cent. This i«, in fact, found to he the case. Moreover, ns
nitrogen is removed from air by means of red-hot magnesium,
the density of the remaining gas rises proportionately to the
concentration of the heavier consiitueiit.

Second. This gas has been concentrated in the atmosphere by
diffusion. It is true that it has not been freed from oxygen and
nitrogen by diffusion, but the process of diffusion increases,
relatively to nitrogen, the amount of argon in that portion
which does not pass through the porous walls. This has been
proved by its increase in density.

Third. As the solubility of argon in water is relatively
high, it is to be expected that the density of the mixture of
argon and nitrogen, pumped out of water along with oxygen,
should, after the removal of the oxygen, be higher than that of
"atmospheric" nitrogen. Experiment has shown that the
density is considerably increased.

Fourth. It is in the highest degree improbable that two pro-
cesses, so different from each other, should manufacture the
same product. The explanation is simple if it be granted that
these jirocesses merely eliminate nitrogen from ^ an "atmo-
spheric" mixture. Moreover, as argon is an element, or a
mixture of elements, its manufacture would mean its separation
from one of the substances emplo)ed. The gas which can be
removed from red-hot magne-ium in a vacuum has been found
to be wholly hydrogen. Nitrogen from chemical sources has
been practically all absorbed by magnesium, and also when
sparked in presence of oxygen ; hence argon cannot have
resulted from the decomposition of nitrogen. That it is not
produced from oxygen is sufficiently borne out by its preparation
by means of magnesium.

Other arguments could be adduced, but the above are
sufficient to justify the conclusion that argon is present in the
atmospheie.

The identity of the leading lines in the spectrum, the similar
solubility and the similar density, appear to prove the identity
of the argon prepared by both processes.

.\rgon is an element, or a mixture of elements, for Clausius
has shown that if K be the energy of translatuiy motion of tlic
molecules of a gas, and II their whole kinetic energy, then

K _ 3(C/-C,)

C/> and C: denoting as usual the specific heat at constant
pressure and at constant volume respectively. Hence if, as for
mercury vapour and for aigon (§ .KIV.), the ratio of specific
heats C/ : Cz, be r-j, it follows that K = H, or that the whole
kinetic energy of the gas is accounted for by the translatory
motion of its molecules. In the case of mercury the absence of
interatomic energy is regarded as proof . f ihe monatomic
character of the vapour, and the conjlusion holds equally good
for argon.

The only alternative is to suppose that if .nrgon molecules are
di- or polyatomic, the atc^ms .icquire no relative morion, even of
rotation, a conclusion excecdinj;ly improbable in iiself and one
postulating ihe sphericity of uch complex groups of atoms.

Now a mon.iloinic gas can be only an element, or a mixture of

NO. I 3 19, VOL. 5 1]

elements ; and ht nee it follows that argon is not of a compound
nature.

From Avogadro's law, the dersily of a gas is half its
molecular weight ; and as ihe density of argon is approximately
20, hence its irolecular weight must be 40. But its molecule is
idmtical with its at< m ; hi nee its atomic weight, or, if it lie a
mixture, the mean < f the aloinic weights of that mixture, taken
for the proportion in which they are present, must be 40.

There is evidence both for and against the hypothesis that
argon 's a mixture : for, owing to Mr. Crcokes' observations of
the dual character of its spectrum ; against, because of Prof.
r)ls?ew-ki's sia'ement that it has a definite melting po-nt, a
definite boiling point, and a definite critical temperature and
pressure ; and because on compressing the gas in presrnce of its
liquid, pressure remains sensildy constant until all gas has con-
densed to liquid. The latter experiments are the wtll-known
criteria of a pure substance : the former is not known with cer-
tainty to be characteristic of a mix'ure. The conclusions which
follow are, however, so starti ng, that in our future experi-
mental work we shall indeavour to decide ihe question by othrr
means.

For the present, however, the balince, of evidence seems to

I point to simplicity. We have the e'^ore to discuss the relations

to other elements of an element of atomic weight 40. We 'n-

I { lined for long to the view that argon was possildy one or more

than one of the elements which might be expected to follow

' fluorine in the periodic classification of the elem'-nts — elemrnts

which should have an atomic weight between 19, 'hat of fluorine,

and 23, that of sodium. But this view is completely put out of

court by the discovery of the monatomic nature of its molecules.

The series of elements possessing atomic weights near 40

are : —

Chlorine ... ... ... ... 35'5

Po'assium .. ... ... ... 39"!

Calcium ... ... ... ... 400

.Scandium ... ... ... ... 44'o

There can be no doubt that potassium, calcium, and scan-
dium follow legitimately their predecessors in the vertical
columns, lithium, beryllium, and boron, and that they are in
almost certain relation with rubidium, strontium, and (but not so
certainly) yttrium. If argon be a single element, then there is
reason to doubt whether the periodic classification of the ele-
ments is complete; whether, in fact, elements may not exist
which cannot be fitted among those of which it is composed.
On the other hand, if argon be a mixture of two elements, they
might find place in the eighth group, one after chlorine and
one after bromine, .\ssuming 37 {the approximate mean
between the atomic weighlsof chlorine and poias-ium) to be
the atomic weight of the lighter element, and 40 the mean
atomic weight lound, and supposing that the second element
has an atomic weight between those of bromine. So, and rubi-
dium, 85 5, vi/. 82, Ihe mixture should consist of 933 per ccn'.
of the lighter, and 67 per cent of the heavier element. But it
appears improba'ile that such a high percentage as 67 of a
heavier element should have escaped detection during liquefac-
tion.

If it be supposed that argon belongs to the eighth group, then
its properties would fit (airly well with what might be antici-
pated. For the series, which contains

Si"', P^iiiar.'iv^ !^"t.V'/'> and CI ""■>■",

might be expected to end with an element of monatomic mole-
cults, of no valency, i c\ incapable of forming a compound, or,
if forming one, being an nctad ; and it would form a possible
transition to po'assium, with its monovalence, on the o her
hand. Such concptions are, however, of a speculative
nature ; yet they may be perhaps excused, if they in any way
lead to experiments vihichtend to throw more light on the
anomalies of this lurious element.

In conclusion, it need excite no astonishment that argon is
so indifferent to reagents. For mercury, although a monatomic
element, forms compounds which are by no means stable at a
high temperature in the gaseous state ; and attempts to pro-
duce compounds of argon m.iy be likened to attempts to cause
combination between mercury pas at 800° and other elements.
.\s for the physical condition of argon, that of a g.is, we possess
no knowledge why carbon, with its low atomic weight,
shoul I be a solid, while nitr 'gen is a gas, except in so far .is
we ascribe molecular complexify to the former and comparative
molecular simplicity to Ihe latter, .\rgon, with its compara-

354

NATURE

[February 7, 1895

li»eljr low density and its molecular simplicity, might well be
expected to rat. k among the gases. And iis inniness, which
has siTggested its name, suffiiieiitly explains why il has not
pre»iouily been discovered as a constituent of compound
bodies.

We would suggest for this element, assuming provisionally
that il is not a mixture, ihe s>mliol K.

\Vc hive to lec 'id our ihanks to Messis. Gordon, Kellas,
and .Maitl.e«s, who have materially assisted us in the prosecu-
tion of this reseaich.

ON THE SPECTRA OF ARGON.'

Through the kindness of Lord Raylrigh and I'mf. Ramsay I
have been enabled to examine the ^pecuum o( ihis gas in a very
accuiale spectroscope, and also to lake photographs of itsSpectia
in a speciiograph fined with a complete quartz train. The
results are both ineresling and imporiani, and entirely
corroborate the Dmclusions arrived at by the discoverers of
argon.

Argon resembles nitrogen in that it gives two distinct spectra
accoming to the strengih of the induction current employed.
But while the two spectra of nitiOgeii are different in character,
one showed fluted bands and the other sharp lines, ihe argon
spectra both consist of sharp lines. Ii i', however, very difficult
to get ar^ion so Iree from nitrogen that it will rot show ihe
nitrogen flmings superposed on its own special system of lines.
I have used argon prepared by Lord Rayleigh, Prof. Ramsay,
and mysel', and, however free it was supposed to be from
nitrogen, I could always detect the nitrogen hands in iis
spectrum. The*e, however, soon disappear when the induction
spark is passed through the tube for some time, varying from a
a few minutes lo a few hours.

The pressure of argon givirig the greatest luminosity and most
brill ant spectrum is 3 mm. (The best i)ressure fir nitrogen is
75 or 80 mm.) .\\ this piint the colour i.f the discharge i^ an
orangeied, and the spectrum is rich in red rays, t«o beirg
espe. iaily prominent at wavelengths 696 56 and 70564. On
pa.ssing the current the traces of nitrogen hands soon disappear,
and the aigon speclium is seen in a slate of purity.

II the prcs-ure is (urther reduced, and a Leyden jar inter-
calated in the circuit, ihe colour of the luminous discharge
changes from red 10 a rich sieel-blue, and the spectrum shows
an almost entirely dillerent set o( lines. The two spectra,
called for brevity red and blue, are shown on the large map, the
upper spectrum l>eiMg that of "blue " argon, and the lower one
that ol " red " argf>n. It is not easy 10 olitain the blue colour
and spectrum entirely free (rom the red. It appears that a low
eleclr motive force (Jem spark, or 27,600 volt-) is reqiii'ed to
bring out the red, and a high E. M.F. and a very hut >paik foi
the blue. The red glow is produced by the positive spark, and
the blue by the negative spaik.

t have l^kcn photographs tjf the two spectra of argon partly
supeipo>ed. In ih s way their dissimilaiiiy is readily seen.-'
In the spectrum of the blue glow I hive counted 1 19 lines, and
in that ol the red glow So lines, u^aking 199 in all. Of these
26 appear to be common to Ito'h spectra.

The di^apI)earance of ihe led glow anil the appearance of llie
blue glow in argon as the exhaustion increases also resembles
the dianpearance of ihe red line of hydrogen when exhaustion
is raised 10 a high point.

I hjvc iiiepaic'i tulies containing other ga«es as well as nitro-
gen at ilifi'cien' pressures, and have examined their spectra both
tjjr eye obiervalions and by photogiaphy. The sharp line
spccnum ol nitrogen is not nearly so striking in brilliancy,
numlier or sharpness of lines as are those ('f argon, anrl ihe
most careful sciutiny fails lu show any connection between llie
spectra. I can detect no lines in common, lieiween the spectra
of argon and the band s|>ecirum o( nitrogen there arc two or
three clo^e apiToximations of lines, but a projection on the screen
ol a magnified image ol the two spccira p.irily super|)osed will
5hr>w that iwo at lea*t of these arc not really coincidences.

1 have found no other speitium-uivint; gas or va oiir)ield
spectra at all 111 e those of argon, and the appU'cnt coincidences
in kome of Ihc line*, which on one or iwiroctasion^ are noticed,
have been very few, and would probably diiappear on using a

I Abtlraci of a paper I,y Mr. William Cr'H)ke*, F.R.S.
3 Pii •to^rapti* of ihe difTwenl tpectra i,f argon, and other gaseou* *l»eviia
(or rovipa<tv>n, were projected on Ihe Kreeo.

NO. ' ■? ly, VOL. 51 )

higher dispersion. Having once obtained a tube of argon
giving the I'Ure spectra, I can make no alteration in it, other
than what 1 have explained takes place on voijing the spaik or
increasing the exhausiion, when the iwosieitia change (rom
one t> the other. As far, therefore, as spectrum woik can de-
cide, the verdict mut, 1 think, be that Lord Rayleigh and Prof.
Ramsay have added one, if not two, members to the family of
elementary bodies.

The Two Spectra of Argon.
[Lines having intensities below 8 have been omitted.]

Blue.

Red.

Wave-Icngih.

Inlensily.

W.-\vc-Iength.
70564

Intensity.

10

69656

9

640-7

9

603 84

8

6038

S

565-1

9

50 10

9

555-70

10

54965

8

518-58

10

5'6-5

9

5140

10

sot's

10

5007

0

49655

9

493-8

10

487-9

10

470-12

S

46080

S

45095

8

4.';o95

9

4421.5

10

44225

10

439 95

10

43765

<l

43690

9

434 SS

10

433 35

9

433-35

1 9

43005

i ^

429-90

9

1

427 20

8

425-95

S

42595

9

420 10

10

42010

i 10

419-80

9

419 So

1 "

419 15

9

41915

>t

418JO

S

41830

1 8

410-45

8

1

415-95

10

41595

1 to

410-50

S

i

407-25

.s

404 40

s

404 40

9

401 30

s

39485

9

39485

10

39285

8

390-45

1 s

386-85

8

385-I5

10

1

378 oS

9

1

37660

8

372-98

ID

358-70

10

35803

9

357-50

9

349-00

10

1

The totals arc : —

1 19 lines in the " blue " spectrum.
80 lines in the " red" spectrum.

199 total lines.
26 lines common lo the two spectra.

February 7, 1895J

NA TURE

355

THE LIOUEFACTIOX AND SOLIDIFICATION
OF ARGON.'

Havint; been furnished, by Prof. Ramsay's kindness, with a
sample of the new gas, argon, I have carried out ex^jerime-nts
on its behaviour at a low temperature and at hi^h pressures, in
order to contribute, at least in part, to the knowledge of the
properties of this interesting body.

Four series of expeiiments in all were carried out, two with
the object of d-termining the critical temperature and pressuie
of argon, as well as measuring its vapour pressure at several
other low temperature'-', while two other series served to dcler-
mine its boiling and freezing points under atmospheric pressure,
as well as its dm^ity at its boiling point.

A detailed description of ihe-e experiments will be given in
another place ; I sh.ill here give only a short description of the
manner in which they were made.

For the first two expe'iments I made use of a Cailletet's
apparatus. Its metallic manoneler had been previously com-
pared with the readings of a mercury manometer. As cooling
agent I used liquid e'hylene, boiling under diminisheil pressure.
The glass tube of Cailletet's apparatus was so arrangecl that the
portion immersed in the liquid ethylene had comparatively
thin walls {not exceeding i mm.), so as to equalise the external
and internal temperature as quickly as possible.

In both the other experiments the argon was contained in a
burette, closed at both end-, with glass stop-cocks. By connect-
ing the lower end of the burette with a mercury reservoir, the
argon wasiransfeirfd into a narr >w glass lutie fused a: its lower
end to the upper end of the burette, and in which the argnn
was litjtiefied, and its volume in the liquid state m^a-iured. In
these two series of experiments liquid oxygen, bailing under
atmospheric or under diminished pressure, was employed as a
cooling agent. I made use of a hydrogen thermometer in all
these experiments to measure low temperatures.

Determination of the Critical Constants of Argon.

As soon as the temperauire of liquid ethylene had been
lowered to - I28"'6, the argon ea>ily condensed to a colourless
liquid under a pressure of 38 aim tspheres. On slowly raising
the temperature of the ethylene, the meniscus of the liquid
argon became less and less distinct, and finally vanished.

Jjeven determinations of the disappearance of the meniscus
proved that the critical pressure was 50 6 atmospheres ; but de-
terminations of the critical temperature >how slight differences.

quadruple walls, so as to i-olate the liquid from external heat.
Afitr the liquid oxygen had been thus (juured under atmospheric
pressure, a great part of it evaporated, fiut there still remained
about 70C.C. boiling under atmo-phcnc pressure. A calibrated
tube, intended to receive the argon to be liquefie I, and the
hydroL^en thermometer were immersed in the boding oxygen.
At thi- temperature ( - l82°'7') on admitting argon, no appear-
ance of liquefaction could be n iiiced, even when compressed
by adding a quarter of an aimosphere pres-ure to that of the
atmosphere. This shows ihit iis boiling point lies below that
of oxygen. But on diminishirg the temperature of the liquid
oxyg n below — 187^, the liquefaction of argon tiecame manifest.
When liquef.iciion had taken place, I carefully equalised the
pressure of the argon with thai of ihe atmosphere, and regulated
the temperature, so that the state of balance was maintained
for a long time. This process gives the boiling p lint ol argon
under atmospheric pressure. Four experiments gave the
numbers - |86°7, - 180° 8, - 187° o, and -iS?'^. The
lEean is - i86°'9, which I c >nsider to be the boiling point
under atm'tsphenc pressure (740 5 mm.).

The quantity of ar^ton uscil lor these experiments, reduced
to n iimal temperature and pressure, was 99'5 c.c. ; the quan-
liiy of liqnid corresponding ttj that volume of t;as was approxi-
mately 0'II4 c.c. Hence tlie density of argon at iis boiling
point may be taken as approximn ely I '5- Two ether deter-
minations of the den-ity ol liquid aigon, for which Iimployed
s'lli smaller qiianiities of the gas, yielded rather sm Her numbers.
Owing 10 the small amount ol aigim useil for these experiments,
I he numbers given cannot lay claim to great exactness; yet
they proite that the density of liquid argon at its tioiling point
(-187') IS much higher than that of oxygen, which I have
found, under similar conditions, to be l*(24.

By lowering the temjjerature of ihe oxygen to - 191^ by
slow exhaustion, the argon froze to a crystalline mass, resem-
bling ice; on funher I iwcring temperature it became white
and opaque. When the temperature was raised it melted ;
four observations which 1 made to determine its melting point
gave the num'iers : - 189° o, - igo" 6, - 1S9 6, and - j8y°'4-
The mean of these numbers is — 189"'6; ani this may be
accepted as the mel'ing point of argon.

In the following tattle I have given a comparison of physical
constants, in which iho-e of argon are compared with those of
o h r sj called permanent gases. Tne data are from my
previous work on the subject.

Criik.-il
'temperature.

Critical
pressure.

Boiling
point.

Freezing
point.

Hydrogen (llj) .„
Nitrogen (N„) ...
Carbonic oxide (CO)
Argon (A,)
Oxygen (0„)
Nitric oxide (NO)
Methane (CHJ

lielow.

Alinoi

- 2200

20 'O

- I46'0

35-0

-"39-5

35-5

- 1210

50-6

-1188

508

- 93 "5

712

-.8i-8

54-9

I

194 "4

2I4'0

igo'o

-207-0

187 0

-IS96

1827

-J

153-6

- 167 0

J 64-0

-185-8

Freezing
pressure.

60
100

138

So

Density

of gas.

Densily of

Liquid at
boiling
point.

Colour of
liquid.

10

?

1
iCoIourless.

I4'0

0-885

.'

14 0

.\bout

•■

19-9

'■5

"

i6-o

I-I24

, Bluish.

15-0

>

' Colourless.

So

0415

»»

The mean of the seven estimations of the crilical lemperniure
is — 121 ', and this may be taken as the critical temperature of
argon.

The vapour presi^ures at ten temperatures from — 1286 to
I39'i were also determined.

Determination of the JioiHn:^ and Frazin!^ Points.

Two hundred cubic centimetres of liquid oxygen, prepared
in my large apparatus," was poured into a glass vessel with

' Abstract of a paper by Dr. K. Olszewski, Professor of Chemisiry in the
Vnivcrsily of C<'a'Ow.

3 BnlUtin international He V Academic dc Cracovic^ June 1890; also
Wiedemann's Beibldttcr^ vol. 15, p. ag.

NO. 1319, VOL. 5 1]

As can be seen from the foregoing table, argon belongs to
the so c.illed " permanent " gases, and, as regards difliculiy in
liqnefyirg i', it occupies the founh place, viz. l)rtween carhon
m-nnxide and oxygen. lis behaviour on liquefact'on places it
nt-are t 10 oxygen, bu' if differN entirely from oxygen in being
soIiHifiable : as is well known, oxygen has not yet been made to
assume a soli I state.

The high density of argon rendcrcfl it probable that its
liquefaciion would take place at a higher temperature than that

1 T have re-dciennincd t^^e boiling point nf oxygen, using large quantities
of oxvKen. and a hydrogen thermometer of much larecr dimensi'Hs than
previously. The registered temperature is i '3 lower th.in that which I pre-
viously recorded.

350

NA TURE

[February 7, 1895

at wh'ch oxyijen liq ie*i*s. Its nnexoect*dly low cr'tical tem-
perature and boiling point «eem to have some relation lo its
anexpectedly simple molecular constilulion.

After the reading of the three foregoing papers, a discussion
followed, of which we give the most iin|iortant parts.

Dr. 11. E. .\rmstron^ said thai the case for the existence of
the new cmslituent was undoubtedly a very sirong one, .ind
woul t, no doubt, meet with very considerable criticism ihrou.h-
out the oorld. But, apart from the tacts which were brought
forward, there was a portion which was of a wildly speculative
character : viz. the portion dealing «iih the probable naturs of
this new clement. .Apparently the authors were not entirely
sa isfied with the evidence to be adduced from the application of
the Clausius method for the determination of the atomicity of
the gas. It was quite conceiv.able that the condition which Prof
Ramsay pointed out as being the only aliernaiive to ihe one
which was apparently accepted by the authors of the communi-
cation, is a cncciiable condition. It was quite liUely that the
two atoms existed so firndy locked in each other's embrace, tl at
there was no possibility for them to take notice of an>thing out-
side, and that ihcy were perfectly content to roll on toijether
without talcing up any of the energy that is put into the molecule.
The spcctr scopic evidence was not sufficient to justif> the con-
clusion tha' the new cas was a mixture. Tne great difficulty in
.■\ccep:ing ihe conclusion that the gas was an clement having a
molecular weight of 40, and an at niic weight of 40, arose fr'm
the difficulty of placing an element of that kind. All these
matters, however, would have to be discussed later on more
fully: they were matters which could only be discussed very
gradually, as m^rc was leanied about the nc* substance.

Pr.f. .v. W. Riickersaid that ihe one cer'ainfact whi^h came
out indisputably from ihe fac's dcscri'ied by Prof R.imsay was,
that in spi c of ihc doubt wbi.h may have existed on ti e ma'ter
for Ihc last few weeks or months, it was certain that ihey ha I
now a new cons iiucnt of the atmosphere. It seemed 10 him that
one of the most interesting resuls arrived at from the ^<h>si. al
point of view was the fact that the gas was monaomic, arguing
Irom the determine^ ratio of the specinc heats. Tne expC' i<nents
carried out by Lord Rajleigh and Prof. Ramsay made it certain
that the element had the particular ratio of 'petific heats men-
tioned. Well, then the question arose. What followed from
this ? In order ihat this ratio mi.jhl be o'ltained it was necessary
that the atom wi'h which they were de.iling should he rei;arded as
spheiical. In conclusion, I. e said tha' whatever the effect mi4ht be
upon the great chemical generalisation of Mendeleeff', that was,
after all, an empirii.al Law based at present upon no dyna-
mical foundation. If it held i's own in this case, it would,
of course, strengthen the belief in it, bu'. on the other hand,
Ihe law did not stand on the looting of thise great
mechanical generalisations which could not be upset without up-
sc:ting the whole of our lundamcnlal notions ol science.

Prof. Roberts Austen remaiked that in the Bessemer process
alone some ten tons of iron were put into a vessel called a con-
verter. During the conversion no less than ico 000 cubic feet
of airpasscd thtou)>h the fluid iron. Therefore 1000 cubic fert of
argon w.nt «omcwhere. He had taken Bcssrmcr-blown melal
which hi'i n'i" Uccn ireatcd with ferro-manganese, and pumped
out forty limes its volume of gas, of which one-iwentieih was
nilr.jgen. In that nitrogen he had not been able to detect any
argon that could not have come from the water which was
necessarily used in the manipulation. It remained to be seen
whether Ihe argon found its way into Ihe iron, and if it siaycd

there, whether c
different from o '
this 1000 cubic fic.
air or in'o the iron

I/.t!l;l^^ i ■' i

the

UL-iily ihi
hiated, w.i

munualc 1

iiriiiesthat made Bessemer metal

: steel could be tr.iced lo some of

which had either passed into the

gas thfre are no internal iroli>ns of any c- nsequence. Now, if
I' ealoms in a m Ic' ule are so bouni lOi^eh. rlhal hardly any
internal nv tions exist, it wou d, s^' far as spe inc heat is con-
cerned, behave like a monatomic eleii en'. That ihe atoms in
argi n n ay be very cloely connecte ' seems lisely liom its very
g eat chemical in- nne-ss. Heme the <■. nc usi n r.m ihe ratio
of I'S spccihc I eais may be, not iha i' is in nat.nii ■, but that
i'S aion s a'e so biuni toge her in its mOeiu'e that
Ihe m' Iccnle behaves as a win le a.s it ii wis monaiomic."
It was d ffiouli to conceive ihe p ossibiii y of such an eccenlri-
cally-shapid atom as ihat 10 move a 'oui with lUt acquiring a
consideal.le tnt-rgy of rotation. He therefore thoUj;ht that
the only interpretation was that the sias was m iiiatomic.

Lord K'-lvin remarked as to the c md ti n under which
Ihe raiio of the specific heals c uM be e\flcily I •66, Ihat he
did not admit that a spherical atom c uld fulfil that condition.
A spherical atom would not be abs jiutely smooth. In other
words, it iiius' be a Boscovitch point. In fact, ihe only kind of
a'om Ihat could beconceiveii as yiving, in the d>namic.vl theory
of heal, rigoously the raiio i 66 (or the specific hea', was the
ideal Hoscovich ma'hemaical iioint enlowe I wuh ihe |>ropertjr
ofineriia, and with ihe other property of acting Uj^ion neighbour-
ing points with a force depending upon distance.

UNIVERSITY AND EDUCATJONAL
INTELLIGENCE.

Oxford. — A meeting was held on Monday last, in Ihe rooms
of the Regius I'rofes-or of Medicine, at ihe University Museum,
and was at ended by all the scientific professors and leachers
of the University, wiih the exception of i.re or two, who, being
unable to be present, expressed their concmrence hy letter.
It was unanimously resolved ihat a mrmoiial tonnecnng Sir
Heniy Acland's name in a permanent manner wih the Univer-
sity Museum should be esiablished. Sjmpadiv was generally
expressed wiih the scheme already bef re iKc public, but it was
felt ihal a more distinctly peisonal memorial in the Museum
was desirable. The future consideraii ^n of ihe proposal will
be the subject of a S'-cond nieeting to be I e'd shoiily.

Mr. A. Tievor Battje deliveied a leciu e before Ihe Ash-
molean Society, on hlonday last, entiiled " Ice-bound in
Kolgnev." The leciuier narraied his personal experiences,
and gave an account of Ihe manners and customs of the
Samoyedi, illustrated by numerous laniern-slides and specimens,
and he also described ihe orniiholojjical fia'ures of ihe island.

The Siblhorpian Professor of Kuial Economy, Mr. R.
Waringlon, F.R.S., gave his inaugural lecture to a large
audience in tte University Museum on Mondny afternoon.
The ubjccl cl o-en was "The Present Kelaions of Agricul-
tural Art and Natural Science." He deplored the want of
really good agiicultural and horticultural libiaries.

Camhkidc'.e. — The election lo the Sadie ian Professorship
ol Pure Maihemaiics, vacant by the death of P<o(. Ca)ley, will
be held on Monday, February 25, at 230 pm. The names
and testimonials ol candidates are 10 be sent 10 the Vice-
Chancellcr by Monday, Kelruary iS. The elector- .nrc the Vice-
Chancellor (Mr. Austen Lei^h), Dr. Phear, I 'r. Ferrers, Dr.
Ta)lor, Sir G. G. Stokes, Sir R. S. Ball, and Prof. G. H.
Darwin.

The Observatory Syndicate propose the appointment of a
Second Assist ml Observer, at a -tipend ol j^ioo a year. The
appointment will be for five year», and will be made by the
Director, with the consent of the Vice-Chancellor.

■1- of his remark*, referred to Ihe ar-
ity ol the gas. Ol course, what ,
rnienl was ihal the whole, or ^
j;ns,- when it was
V of its ir.inslatory
0.1 10 be attributed to
At first sight il seemed
11 Vic no rotation in the
the gas. I'bat condition wa^ nfl by the suggestion
licen put forward, and wliiili had also been c im-
by Prof. FitrgcraM, in the fdlowing woids :
"The leason why Ihe ratio of sjiecific heils of l"66 is sup-
poH'd lo piove monalomicily in a ga-s ii because in a monatomic

NO, 1319. VOL. 51]

SCIENTIFIC SERIALS.

AmtrUaii Afetiorological Journal, January. — Solar mag-
netism in meteorolog), by Prof. F. II. Iligelow. This article |
contains some general lemaiks on the pie.'cnt siaie of the i
pioblcms aiisingoul of Ihe relations thai have been Iraccd by >
the author's study of solar magnetism and its influences upon
mcieorological phenomena. Piol. Ibgc.ow endeavours to show
Ihat the uually accepted mode of propa^jaiion of energy from
Ihe sun to the earih is nol Ihe only one iha: exisis, and suggests
thai another possible mode is due lo polarised solar magnetic
force, such as surrounds a magnet. '1 he progress ol ihe investi-
gallon was inode in ihicc dl^tlncl stage- : (i; llie detection of
the Hue period ol the sun's rot.ilion ; (2) ihc uelcrmination of

February 7, 1895J

NA TURE

357

1

the intensity of the solar niaj;netic fieM frnni mer'Hian to meri-
dian of iht- sun ; (3) the disc .xe-y < f the inveision (tf the so'ar
magreii-m in tt-riHin pfT'Oii-. The aiillior ex|irtsse^ iKei>|'ininn
that the convecii*nal hvi'othesis of c)cl'»nes is uittena'tle, ami
endeavours to sh 'W, fi-itn nn fxam-narion of the Anifiican
meteorological curves lor thr years 1878-93. that the tliree S)S-
tems — the one at the sun, thatif t'le mayneiic field in the
northern heoii-pliere, and 'hat o( tl.e Ami-rtcan mrleorolo^ical
field — vary toj;eiher in lilock f oni ye ir 10 year. — Variations in
the cliarac er ol the ••ei^ois, I'y 11. G-iwItirr^p The divisioir
of the year into four sea-on-- is iraHiiioual, hui when measmcl
as phases ol wea'her, it is n'l' possible to fix these periods
within definite liiniis. The author's investigation leads htm to
conclude that thepiimal cause for ihe vaiiations in thecharacier
of the seasons must lie traced h.ick' thioiinh all ihe tfTecis of
diurnal and seasonal iiiso aiion, and of the cjtlonic stoims m
the lower atmosphere.

Wiedemann s Annnlen der Physik und Chemie, No. r, 1895.
— Electromagnetic pull ng foice, 1)) Max Wiber. An iron
wire whose length i* very l real in i oifjiari-on with its thickness,
experiences a puning fircr piiporlional to the he'd intensity,
its magnetisation, and its stcinn at arei, wh'n its end lits in a
magnetic field, and iis axis is pa'allcl to the lines of foice.
If the lines if (orce are perpendicular to the axis of the wire,
it al-o cxiemnces a puling foice alont; its axi-, which is,
however, sinali-r in iron than the loinur lorce. 'J'he ratio of
the pull along 'he lines of lorce to that across it is abi ut roo
in moderate fields (uch as II = 100), but with in-reasing
strength ol field ii (|uicUly decreases, and appears to apf^r lach
unity. — Differi nl fitriii^ 01 n ulnple res inante, by V. Hjciknes.
The conclusion usuall) drawn Irom Sarasm and de la Rive's
experiments with eleittic waves pri pagated along wires, that
there are as many stationary wave >)s tms as nodal systems are
exhibited by the nsonalor, is erroneous. The.^e jieriods are
due to the resonator, which resounds to a simple sine
oscillation at dtftercni pidnis. The on'y reliable method is to
study the wave sy-ienis with " inoifTermt " indicators, such as
spark micrometers, electrometers, bolometers, and small
thermo-couples. The difYerence between electric waves and
light waves is that the l.ilter are continually maintained, while
the former are dampe t. — Total reficclion of light in dense
crystalline substances, by K. Camerer. The measurement of
the index of refraction of substances of a ciyslalline structure
by total reflection is at em ed with various difficulties. In
some cases, ihere i no well-rtcfine I limit of total reflection, as
in the case of parafhn or bce>wax planed or cast on mercury.
When the same sul'Stances aietast or pressed on ihe surface of
the prism, two limits, pjlarieil at right aigles to each other,
are observed. The author explains this by supposing that in
the latter case the substances crystalli-e in a uniaxial form,
with their optical axes perpendicular to the surface, while in
the former case they aie biaxial. — Elastic behaviour of zmc at
different leni] eratures, by Kiuh Zimarsky. It appears that
the suddenness or otherwise of the cooling of cast zinc has no
very decided ii lluence upon its biitlltness. It is not hardened
l>y rapid cooling to anything like the extent that iron is.

UtilUlin de la Sociele dcs NaltiralhUi de A/oscoii, 1894, No.
2. — On the Mastodons ol Russia, and their relations to the
Mastodons of other regions, by Mme. Marie I'avlova, being
a summing up of her larger woik, now ready for print. Its
conclusitns ate : (l) It is the gioup Mmiodon Zysoiof/icdoii,
represented liy A/. Borsovi^ A!, ohiotietts^ and their varieties,
which had a ver) gieat spreading in south-west Russia during
the Miocene and the Pliocene ptnods. (2) None of these forms

-pecific to Ru>sia, all having been widely spread in West
l.urope and North America. (3) The group of y)/. Jiuiiolophodon
IS only known till now ihrougli a veiy limited nuuiber ol speci-
mens ol M. aiveitiemis, while this group is widely represented
in West Euiope, Asia, and America. (4) The close resemblance
between the INlastrdons of Eurasia and America confirms once
more the connection whith existrd between the two crnlinenis
duiing the Tertiary peiiod. — The Post-pliocene mammals of
East Russia, by Piof. S'ucktnbcrg (in Fiench). They are :
Rhincceios, lic/wi:/ii>itis, Fischer, and /\h. A/miii, Jaeger ;
Elasmol/itiiiim J-ischeri, De niaitst, which has never btcii
found in Perm, Ufa, V)aika, Kazan, Nizhni Novgorod, and
Simbirsk, but only luiihir south, i.e. in Samara, Penza, and
SaralciV ; £ijuiisial alius, very common — the fossil horses having
already been made the subject of special studies by Mme.

NO. 1319, VOL. 51]

Pavlova ; Ceiviis Ini annus, C. tiaphus, C. aJees {Aires faimata),
anrl C. me;^iiceros {A/igactros /tidirviius). Owen ; Auti ope saiga,
Palla- ; lioi pri'Cus, and b'os pritniyetiius, the latter very rare ;
Ovibos mofchahn, WnTiV'Wi: (O. Jjssilis, Ru im-jer) ; Sus, sp. ;

E/fpli<is primigttiius, very c mmon ome molars off-ring great

(livergtnces fiom the usual ly] e — and another yet undcte' mined
>pi cies of Eliphas, of which one molar is kept in the museum
of Kazan ; ttiough like as a whole lo a mammoth tooth, it
has well deiiiied peculiarities of structure ; Castor fiber ; Ursus
atctos ; and an undetermined species of Cants. All these
rtniains have rarely been found in situ, but chiefly in le-
modtllefl river deposits. — The second part and conclusions of
the Work of B. Lwolf, on the embryology of mammals. The
current ih- ory ol gastrulation is shown not to be sut'ported by
direct obstrvation, and a new theory is proposed. — On ihe use
of Houguer's formula in the study of gravitation anomalies,
by Plot. Th. Sloud-ky (in Fiench). — On some land shells
Collected by M. K' ishtafowitsch on the Vorobievy Ilill-, near
Moscow, by Ur. Zickendrath, They belong to species now
quite common in Middle Europe (Hyalinia, H^- ix, Citiella,
Pupa, Siiccinea, &c.}, and originate fiom the ptriod when the
Voioliievo plateau was covered with thick marshy forests; they
can by no means be considered as belonging to any ice period. —
EniomoIOi^ical and botanical notes from Sarcpia, by Alex.
Becker (in German).

SOCIETIES AND ACADEMIES.

London.

Geolcgical Society, January 0. — Dr. Henry Woodward,
F.R.S., President, in the chair. — The formation of oolite, by
E. B. Wethered. In previous communications the author has
described pisolites formed by the growth of Cirvattel'a, and some
true oolitic granules having a like origin. He had previously
expressed the opinion that all oolitic granules are of organic
origin, and the facts described in the present paper give support
to this view. He described the form of the granules, which
frequently exhibit a series of concentric layers of calcium car-
bonate around a nucleus, and also dark slri^ and patches, the
former placed more or less at right-angles to the nucleus. The
concentric layers often exhibit an irregularity which the author
maintained to be incompatible with their chemical origin.
Again, granules are found made of calcium carbonate occurring
in two forms — a clear crystalline portion representing the organic
structural pait, and an amorphous portion consisting of oidinary
catbonate of lime, which is either infilling or secreted material,
possibly both. In discussing the origin of the crusts around the
nuclei the author treated of the radial structure which is so
maiked a feature in the crust of oolitic granules. This structure
has the appearance of light and dark stria: when seen by re-
flected light : the light are tubules which have grown at right-
angles to the nucleus, while the dark are secondary foima-
tions. He referred to Rolhpletz's description of the oolitic
granules of the great Salt Lake, \\hich are slated to have
originated from the growth of lime-secietiug algse, and thinks it
possible that the fossil forms are of like origin, though not
necessarily due to organisms allied to algse, and possibly even
lower in the scale of life. In his opinion Girvanella — the first
type of oolite-forming organism discoveied — is simply a tubule.
A long discussion followed the reading of the paper. "The Presi-
dent thought that the author had placed evidence before the
meeting sufficient to prove Ihe organic origin of many of his
oolitic gianulcs. Mr. G. F. Harris believed that while most
geologists would possibly agree as to the organic nature of the
tubules in the pisolites rtferied to, they would not be unanimous
in recognising the tubular stiuctureinmany of the oolitic granules
shown. Many of the features presented by oolitic granules, and
brought lorwardbylhe author as evidence of the organic origin
of oolite, could be explained by the alteration effected in them
since their original foimation. Mr. E. '1. Newton agreed with
the author that Ihe irregular tubules teinicd Ctrvanelia, and
seen sometimes within and sometimes on the outside of oolitic
granules, were of organic origin, but he thought that the
chaiaclerislic concentric and radiated structure of oolitic
granules was entirely different, and not due to concentric
lul ules. Dr. G. J. Hinde did not think thai the author was
right in his interpretation of the concentric layers so common
in oidinary oolitic grains as tubjilar forms ol growth. In his
(the speaker's) opinion these concentric lines might indicate

35S

NATURE

[Februakv 7, 189;

layers of growth, but they were not in any sense tubules. Mr.
A. C. Sewaid expressed himself in agreement with the main
contention in reference to the occurrence of or;janic tubular
structures in the ooliic grains described by the ;iuihor ; hut the
expUnalion offered by the author with regard to the radiating [
stnicture sern in certain grains he regarded as unsatisfactory,
their general appearance being much more sug^jestive ol
secondary changes in the oolitic grains, which had no direct
connection with the CiVtvj«^/Aj-tubules. Prof Judd said that as
far back as 1S62 the eminent botanist Dr. Ferdinand Cohn
had pointed out the important pan played by alR.-c in the for-
mation of the Sprudcl>lein of Carlsbad and other calcareous
rocks. At a laltr date Bornd, the eminent French algologist,
had insisted no less strongly on the work done in perforation
and breakinc-up calcareous fragments by other plants. The
speaker was inclined to regard snme ol the structures (especi-
ally certain of the radial ones) as due to the action of destruc-
tive rather than 10 constructive organisms. Mr. H. B. Woodward
referred to the mo<lern formation of oolite-grains in waters
charged with bicarbonate of lime, whether in proximity to cal-
careous spiings or coral reefs. He thought that the slides
exhtbitrd by the author did not show connection between the
Girvanilla and the concentiic and radiate bands of oolile-
grains. Hiof. -Sceley beliexcd that some of the photographs
exhil iied a structure which, although imperfectly preserved,
might be comi'ared with the sections of tiullipoies which the
speaker brought bef)re the British Association at Ba'hin 1S8S,
as evidence that some grains of oolite are of organic orijijin.
Mr. Kutlcy said that, with regard to the nuclear poitions of
some of the sections projected upon the screen, he considered
that the author was probably correct in ascribing an organic
origin 10 the interlacing tubular structures; but, so lar as the
peripheral portion of the oolitic bodies was concerned, he be-
lieved that it presented no appieciable difference from that of
ordinary calcareous concretions of a purely inorganic origin :
similar radiating and concentric structures being also met with
in the sih' rulites frequency present in eruptive locks. Prof.
.A. II. Green also spolie ; and the auth<ir replied. — On the Lias
Ironstone around Banbury, by Edwin A. Walford. The ferru-
ginous limestone of the Middle Lias of the Banbury district
occurs practically within a ten-mile circle around Banbury. The
stone (the Marlsione of the Geological Survey) is an "oolitic"
cyprid limestone with much molluscan and crtnoidal dOliris and
some quarlz-grains. The author described the lithological
charac ers of the rock, and their variations, as traced laterally
and vertically, giving a full description of its local devel •pmeni,
with a detailed account of the seclims in the principal ex-
posures.— Notes on the geology and mineral resources of
Anatolia (A-ia Minor), by \V. V. Wilkinson. The route
traversed bom northwards to southwards through the city of
Broussa lay thmugh a country composed of sedimentary rocks
(largely limestones with s^me .shales and conglomerates). In
the miiuniains melnmorphic rocks were met with, and also
ign- OU.S rocks. The principal igneous rocks noticed are
granites and serpentines ; in the latter chrome iron-ore occurs,
and IS w'liked.

Physical Society. January 25.— Mr. Medley concluded the
reading III a paper, by Prof. Ayilon and himself, on tests <.f glow-
lamps, which was commenced at a former meeting. Wiih ihe
newer lamps employed in these tests, it was found thai candle-
power, current, and candles j er wait, all rose as Ihe lives of the
lamps increxsed. The author-, being surprised at this result,
took care 10 satisfy ihcmsrives that the effect observed was due
neiiher 10 change in the resistance ol their manganin potcnii-
omeier atrip, nor lo uncertainly of contact at the sockets of Ihe
lamp>. Starling again with new lamps, they lound that in all
cases the ln,ht given out was greater alter the lamps had been
glowing for jome lime than it was «hen they were new. In
Ihe earlier tests a con iderable falling ofl in candle-power had
always Lnkcn place after the lamps hail been rui ning for some
time. Further, while the globes of the earlier lamps were
alway- mucli blackened, even afiera run of a few humlred hour-,
and no became comparatively useless long before ihe filament
brole, the Edison-.Swan lamps now examined showed
hardly any blackening, even when Ihe filaments lasted over
1300 hiinr». The rise in candle-power was always accompanied
by a ri»e in current, which »a», however, proportionally much
«n alier, so that the con iimpiion of power 1 er candle was
actuall) leu alter the lamp had l>een running fifi) hours than it
was at the beginning. Among ihe cunclusions drawn by the

no. 1319, VOL. 51]

authors were the following : (<i) When a group of Edison-.Swan
lamt)s, marked loo-S, are run at 100 volts, and each lamp as
its fil.iment breaks is replaced by a new one, it may be ext>ected
that the light given out will never subsequently be as small as
when all the lamps were new ; {'A an Edison-Swan lamp,
marked 100-8, when run at 100 volts will give an average illu-
mination- of about 10 candles, and will absorb on an average
power of about 4'3 w,atts per candle, so that such a lamp must
be regarded as a 43-wati lamp, and not a 30-watt lamp, as is
frequently stated ; (<■) the maximum rise of light recorded
during the life of any lamp was 45 per cent. ; (li) with lamps
of the type examined, there is no point at which it be-
comes economical to discard a lamp before its fila-
ment actually breaks ; (e) no marked economy can be gained
by overrunning such lamps (i.e. by using pressures exceeding
100 volts). Prof. Ayrion mentioned that the improvement in
glow-lamps after running for some time had been attributed to
an improvement in the vacuum. Experiments made on new
and used lamps by means of an indue ion coil showed that the
more a lamp was u-ed the better the vacuum became, hut he
(Prof. Ayrion), though at first inclined 10 adopt this explana-
tion, had since found that though in all the lamps examined
the progressive improvement of the vacuum was equally
marked, the increase in candle-power varied between very wide
limits, being very consiierahle in some lamps, and hardly per-
ceptible in others. Prof. Kiicker asked if it made any differ-
ence to the life of a lamp whether it were kept running con-
tinuously until the fibre broke, nr were run for periods of a few
hours, alternating with intervals of rest. The latter case would
more nearly conespond with the conditions obtaining in prac-
tice. Prof Ayrton replied that Ihe lamps were kept running
during the night, and were disconnected during the day. — .\
paper, by Prof, .\nderson and Mr. J. A. McClelland, on the
temperature of maximum density of water and its coeflicient of
expansion in the neighbourhood of this lemicrature, was read
by the secretary, Mr. Elder. The dilatometer method was
used, but the bulb of the instrument coniained a quantity of
mercury, determined by experiment, which for the range of
temperature concerned wa- such as to secure the constancy of
the remaining internal volume, occupied by water. The ob-
served changes were thus the real, and not the apparent changes.
The bulb W.1S furnished with a graduated tube of small bore,
bent twice at right angles, which served at the same time the
purpose of a ground glass stopper. (The joint was made
waier-tight by a little Canada balsam.) To determine the
coefficient of expansion of the glass, the bulb and tube were
filled with mercury at o" C, and healed up to .about
97 C, the necessary weighings being afterwards per-
formed. The coefficient of expansion of mercury being
known, the number of grams o( mercury 10 be kept in the
bulb during the experiments on water was calculated. The dilato-
meter was next filled with (thoroughly boiled) di-tillcd water
at about 8° C, the stopper-end of the graduatetl tube inserted,
and the free end dipped under menury, giving at 4' C. a
column of mercury whose changes of level could be observed.
A thermometer was placed with its bulb close to the middle
part of that of the dilatometer ; both being immersed in a water-
bath which could be cooled by the addition ol ice-cold water,
or healed by radiation from surrounding objects. The ther-
mometer used was graduated to tenths of a degree, and was
compared with two similarly graduated ones by dillerent
makers. The two latter agreed very closely with one another,
and one had a Kcw certificate showing no error in the read-
ings. Temperatures were written to the fourth decimal place,
but accuracy to this extent was not claimed. Three sets of
experiments were made, and for each a corresponding curve
was drawn. In the first, the water was at atmospheric pressijfc;
in the other two, at ijand 2 atmospheres respectively. Coi|-
responding to these thice pre-surcs, the temperatures of maxi-
mum ilen-ity found were 4°' 1 844 C, 4° 1S23 C., and 4" 1756C.
The value 4''l844 C, corresponding to atmospheric pres»ure,
is greener than tint generally receiveil. Mr. Rhodes thought
that suflicieiil precaution had not been taken to accurately cali-
brate the thermometers. He doubled whether temperatures
read in the manner dcscribeil could be relied upon to much less
than o I. lie iliil not see thnl any real advanage was gained
by having mercury inside ihe dibiiooir-ier to compensate for the
expansion of the glass. Mr. W. Watson thought that ihe
mercury within the vessel would cause further uncertainly by
tending' to produce distortion of the glass. lie pointed out

February 7, 1895J

NATURE

359

that in the case of water at maximum density, there would
be praciically no convection currents, so that equalisation ol
temperature would be very slow. As the bulb used wa^ aboui
8 cu). in diameter, and all the experiments were made with the
temperature rising, he thought that this would account for the
high value obtained for the temperature of maximum densiiy.
Dr. Burton thought a distinct advantage was gained by com-
pensating for the expansion of the gla^s. The value- obtained
in different experiments did not seem to be highly concordant.
Prof. Rii>;l<cr thought that ihe criticisms which had been passed
were, for the most part, just. For such measurements as those
recorded, it was not sufficient to know the correciions of the
thermometer reading- at a few isolated points ; the portion
of the stem over which the readings were taken must be care-
fully and minutely calibiaied. The Kew ceriificate not only
ignored err-rs of less than 05° (as mentioned by the author ),
but it only gave conections for a small uumber of temperatures,
separated by considerable intervals.

Linnean Society, January 17. — Mr. C. B. Clarke, F.R.S.,
President, in the chair. — .Mr. George Murray exhibited lantern
slides rcpreseniing a new part ol /"a. /yM^fa, consisting ol a
cup-shaped recepiicle in which Fackytheca was found by Mr.
John Sloriie, ol Cardiff. The walls of the cup are composed
©f railialing chambers like those of Acttabuiaria, and in the
centre there are iraees of an axile structure. Mr. .Murray con-
sidered that this discovery only made the interpretalioii of the
nature ol tarhylkcca more difficult than ever. — Mr. Arthur
Lister exhiliiled ami made remarks upon a Landrail ' Cre.x pra-
lensis) which had been found, a few djys previuu-ly, near Ax-
minster, in Devonshire, where it had been killed by coujing in
contact with telegraph wires. The occurrence in midwinier of
a bird whicn is a summer visitor to this country, .seemed 10 him
to be worth notice. — -Mr. J. E. Harting exh biled specimens of
northern sea-birds which had been driven upon the east coast
of England during recent gales ; amongst 01 hers, the Little Auk
■ {A/£rgultts alba)y of which great numlters had ctmie ashoredead,
or in an exhausted condition ; the Litlle Gull {Lams minutiis),
obtained at Whitstable on January 5 ; and an example of
Briinnich's Guillemot, Uria hriinnictiii^ Sabine {Trans. Linit.
Soc. xii. p. 5jii), a species which, though abundant in Green-
land, North-East Iceland, and .Spiizbergen, is of such extremely
rare occu-trence on our coasts, tnat not more than two or three
authenticated instances of Us appearance here have been
recorded. The specimen exhibited had been forwarded by
Mr. W. J. Clarke, of Scarborough, near which sea-port it was j
-hot on December 7, 1S94. — A paper was then read by Mr. i.
H. Burkill, on variations in the number,of stamens and carpels.
Of Stellaria media about 5700 flowers were examined, showing
that towards the end of the file of the plant the number of sta-
mens becomes reduced. Kaiiiiiiculiis Ficaria (nearly 800
flowers) showed that towards tne end of the flowering period
both stamens and carpels become reduced in number with-
out their proportion being changed. Smaller numbers
were examined of Caltha palustris. Ranunculus arvensis. A'.
biilbosus, 1 halictum flaviim, Bocconia cordala, Prunus Padiis,
Prunus Lauro-cerasus, Craticgus Oxycanllia, Rusa canina,
^)uerciis Ilex, and Sagillaria montevtdensis, all of which
showed, either in carpels or in stamens, a reduction in number
towards the end of the flowering period. Of other influences
besides age which affect the number of parts, temperature
might be one, but nothing could be safely assumed. — Of a
kindred nature was a paper by Mr. A. G. Tansley and Miss E.
Dale, on variation in the floral symmetry of Fotcntilla Tor-
mentilla, Necker. This paper, of which Mr. Tansley uave an
abstract, was mainly a recoid of variations tending to alter the
normal letramerous actmomorphic symmetry of this flower.
From his observations it appeared that independent variations
of the epicalyx is considerable, but is probably mainly due 10 a
tendency of its segments 10 revert lo a primitively double con-
dition. The residual independent variation is small, and
roughly equal to that of the calyx and corolla. The number of
stamens is more variable, and the carpels extremely so. Corre-
lated variation of all ihe whorls is frequent, and produces
deviating lypes of symmetry in about 3 per cent, of the flowers
examined. The seiies of groups into which the various devi-
ating types mifjht be said 10 fall, illustrated the shifting nf the
centre ol variation from the penlamer lus type of allied fl iwers
to the letramerous lype of P. Tarmentilla. — A discussion fol-
lowed, in which the President, Mr. II. N. Ridley, an t others
took pan, and Mr. Tansley replied to the criticisms ollered.

Chemical Society, January 17. — Dr. Armstrone, President,
in the chair. — The following papers were read: Ocacetyl-
maltose, by A. R. Lingand J. L. Baker. Herzfcld's description
of octacetylmaltose is in many respects erroneous. — .Action of
diasla-e on starch, by A. R. Ling and J. L. Baker. The
isomaltose obtained by Lintner by the action of diastase on
starch is not a pure substance. From the product of hydrolysis
of slarch paste by diaslae, a triosazone was isolated ; one of the
iniducts of the aclion is therefore probably a triose CigHj^Ojr,.
—New derivatives from a-dibromocamphor, by M. O. Forsier.
Fuming nitric acid dissolves a dibromocaifphor with formation
of a neutral substance CioH,.,Rr„0., ; this on alkaline reduction
yields a monobromo-rieiivaiive C,„II].,BrO., The latter sub-
siance is c 'nverled into a nitro-derivative C,,H]..BrNOj by
niiric acid. — .\cid sulphate of hydroxylamine, by E. Divers.
Crystalline hydroxylamine hydrogen sulphate is prepared by
acting on hy-iroxylamine hydrochloride wiih the calculated
quantity of sulphunc acid. — The hypophosphites of mercury
and bismuth, by S. Hada. Hypophosjihiies of thecomoosition
HgH.,POo, HsjNOa, H„0 and Bi(HjPO„)3, H.,0 have been
prepared.— Kamala, part ii., by A.' G.'Perkin. The three
acids previously obtained by the oxidation of roltlerine are now
shown to be ortho- and paia-nitrocinnamic acids and para-
niirobenzoic acid. From the composition of its metallic
derivatives roltlerine would seem to have the composition
CsjI'siiOj.COOH ; it yields a crystalline subsiance. roltlerone
Cj,|H^;i),;. when boiled with sodium carbonate. — The action of
aqueous poiassium cyanide on gold and stiver in presence of
oxygen, by .1 . S. Maclaurin. The solution of gold or silver by
poiassium cyanide solution is dependent on the presence of
oxygen, and ihe rate of solution is proportional lo ihe quantity
of oxvgen present, and to the coeflicient of vise >sity of the
solution. — The crystalline forms of the two dimeihjlpimelic
acids, by \V. J. Pope. — Oxidising aclion of ammonia solution
on some melals, by W. R. Hodgkin-on and N. E. Bellairs. —
Ac.ion of magnesium on some phenylhydrazine compounds,
by W. R. Hodgkinson and A. II. Coote. Complicated mix-
tures of produc s are obtained on boiling acetyl- or benzoyl-
phenylhydrazine with magnesium filings.— Refraction equivalents
of the elements and the periodic law, by R. M. Deelcy.

Paris.

Academy of Sciences, Januaiy 28. — M. Mareyinihe chair.
— Prepaiation and properties of boride of iron, by M. Henri
Moissan. A boride of iron of the composiii m FeB is obtained
by heating together iron ar.d boron, best in the electric furnace.
It forms brilliant grey crystals which remain unaltered in air or
dry oxygen. Its density is 7 1531 18° C. Its chemical behaviour
with ordinary reagents is fully described — On Fourier's pro-
blem, by M. E. Le Roy. — On ih; exact levelling op-rations
recently carried out in Russia, by General Venukoft". In a total
of 1090 stations scattered through .ut Russia, no altitude was
(lete.mined greater than 33S metres The most important result
of the survey was the cs ablishment of the identity of level of
the Baltic, Black, and Azov Seas.— On the solution of solids in
vapours, by M. P. Villird. — .\ction of an electric cuirent on a
number of metallic sulphides in ihe fused slate, by M. Jules
Garnier. Sulphur is gradually eliminated from ihe fused mass
out of contact with air, the copper retaining a greater proportion
of sulphur thnn iron and nickel in an ore containing the three
sul| hides.— On some properties of bismuth sulphide, by M. A.
Ditte. The production and properties of crystalline bismuth
sulphide, made in the wet way, are describe!. A remarkable
double compound with poiassium sulph dc, Bi.Sj. 4K„S . 4H«0,
is obtained in very sharp and brilliant redJish-yellow. trans-
parent thombohedra from a solution of BioSjin poiassium sul-
phide. The crystals cannot be kept in a moist a' mosphere.as water
readily blackens ihem. — Influence of th surrounding medium on
the transformation of amorphous zincsulphide, by M. A.Villers.
— On carbonylihlorobromideanddibromide, by M. A. Besson.
The author obtains the substance": COCIBr and COBr, by the
imeraciioni-f COCIjand BBr^. They arc both partially decom-
po oi by distilla ion in air. They are very dilatable 1 y heat,
and^posse-s very irri aling vapours In contact with mercury at
100° in sealed lubei they suffer total decomposition, but are only
slowly ajied on by coll wa er — Mixed e her aid ammonium
derivatnesof hexameihyl- r amido-iriphenylinetl ane. liy M. A.
Ro-Ciisiiehl — On acetic eters (rom sugars, by M. C. Tanret.

Ihe author shows ihe various reactions given wiih diflT.rent
tlases of sugars by acetic acid in presence of fu id sodium
acetate and ol zinc chluride respectively. He describes ihrce

NO.

(3 IQ. VOL. 5 I

.^6o

NA TURE

[Februaky 7, 1895

pentacetyl compounds derive! frjm glucose under the natnei
a, B, and f ponta;ctines. — On hctane'hylcno r\mine, by M.
Dclcpino. The molecular weight, rfetermined by the cryoscopic
melhod, requires the formula CsH,jNj. This result is fully
con6rme<l by examination of its reactions and by the chnracter
of its niiroso-dcrivatives. — Oo the seeds of Ci^w/a from French
Congo, by MM. H. Lrcomte and A. HcSeri. The oil obtained
from these seeds appears to consist wholly of triolein. —New
facts relating to the mechanism of hyperglycaemia and hypo-
glycemia ; influence of the nervous system on glucose formation
and histolysis, by M. M. Kaufmann. The conclusions arc drawn
that : (1) in hyperjjlyaeiiiia, and hence in diabetes, glucose for-
mation and histolyiic resorption are active; (2) in hypo-
glycemia, (jiucose formation and histolysis are diminished ;
(3) section of the medulla near the brachial enlargement
modilies the action of the liver ; this organ then supplies the
blood with less sugar and more glycogen ; nutrition is
also generally modified, the storage power of the tissues is
augmented and their hislolytic resorption dimini-hed. — On
some points in connection with spermatogenesis in \.\\k Sitacicns,
by M. Armand Sahalier.— On the fixation of .■hJf'haUs by the
byssus, by M. Louis l!r>utan. — On the attachment of Amoebx
to solid bodies, by .M. Felix Le Dantec. — Histological observa-
tions on the functional adaptations of the epidermic cell in
insects, by M. Joannes Chatin.— On a new practical process
for the estimation of calcium carbonate in arable soils, by M.
.\ntoine de Siporla. The estimation is based on the alteration
in density of a moderately dilute solution of hydrochloric acid
when chlorides are formed from soil con-tiiuents and dissolved.
— On some Micrococci from Ihe StJ/ihanicii, upper coal-
measures, by M. B. Renault. — On mildew : its treatment by a
new proce-s, " lysolage," by M. Louis Sipiere. — The mulberry
disease, by M. A. Prunel. The disease described appears to
be due to a fungus allied to ClaJochytrium vilicolum. This
fungus is named by the author ClaJochytrium, M iri. — Re-
searches on the conditions which have determined the princioal
characters of the lunar surface, by M. Stanislas Meunier. — On
'.he rjle of our sensations in the perception o( mechanical
phenomena, by M. V. Clementitch de Engclmeyer.

DIARY OF SOCIETIES.

London.

THURSDAY. February ;.

Royal Socihtv, al 4.J0. — On the Applivation o) the Kinetic 'Ihenry to
Dcil<e Gues : S. H. Kurbu'y, V. R b.— On the Abclian System ot DilTcr-
cntial Eiiuationi, and thrir R-itional and Integral \ gct>raic Integrals, witli
a DitcusM .n ol ihc Pciodicily of Abcli^n Functions ■ Rev. W. R.
We»tr .pf-KobcrU. — The Os -ilUtioiu of a Rotating Ellipsoidal Shell con-
uining Fluid : S. S. Housh

LlNHK^N ■vK.tSTV, at 8 —I he Comparative Morpholosy of the Galeodidx:
H. .M. Bernard. -New Marine Alga from Japan : E. M. Holmes.

.SociKTV *.■? Ka I ivUAktk.s, at 8.30.

Chemical Socitiv. at 8 —The f.lcctromolivc Force of an Iodine Cell :
A. P. Laurie.— The Acti m of He^l on E. hylic fJ-amidocrotunalc: Dr.
Collie.— The Acidimctryof Hydroltnoric Acid : Prof Ha^a.

LoMCMN Institution, at 6.— The Germination of liarley : A. Gordon
S«lamon.

FRIDAY, Fkhkuarv 8.

ROVAL Imstitutiin, at.).— Tnc Anti-toxic Serum Treatment of Diph-
theria : lir. G. Sim> Wood head.

Pmvsicai SotiiiT«,at s.— Anual General Meeting..— An Exhibition of
Si-nple App.,r*tu»: W. B. Croft.— On the Tin Cnromic Chloride Cell :
S Skinner.

RoTAt. A-.TwnioMirAL SoctRTV, at3. — Annivenary Meeting.

•*■■: Ehginbers. at S.— The Construction and Main-

• " ii. H. Godfrey.

Ma. . V, at 8.

Clinic m. -'>■ ".if rv, -.i ^.

SATURDAY, FicnKUARV 9.

RoTAL Botanic Socmrv. at V4S

-S USD A y, Fkhruarv 10.

SvMOAT LicrURK Socmrv, at 4 — .)ecp Sea Exploratiooi in their Geo-
logical Bearingi : Dr. K. I> Roberts.

MO.WDAV. hHinjUARV II.

London Institution, ai 5 -Iruib ar.d Kalsthood as to Electric Cur-
rent in ihe Body : Prjf Victor llorsley, K.k.S.

RoVAL Gi.iCRAriitCAL Socibtv. at 3 30. — North. Went Brili.h Guiana :
G. O. DuoD.— A Joumepr in Germaa Ne« Guinea: Captain Cayley

So' I — Meant for Verifying Ancient Embroider'es and

Ca-' —A Simplified and Improved Form of Photo-

E I .lylor.

R I Anciiitects, at 8.

Ua

/LIES DAY. FEimuAnv 11.
RoTAL 1»«titution. ■! }.— The InUrnal Framework of Plant» and

An .i.al> : Pf .f C. Stewart.
I"s' 'VIL «!.< iiKiMs, al 8.— Pip;r to he further ditcuxed :

I .•: and Elccincal KeguUtion of Sicam-Eoginei : John

N\J. 13 19, VOL. 51]

ANrHRnrOLOciCAL INSTITUTE, at S.30.— The Ethnographic Survey of the
United Kingdom : E. W. Brabr>>ok. Prehistoric Kemains in Cornwall,
Part I. : A. L- L'wis —On the Northern Settlements of the West
Saxons: Dr John Bcddoc. F.R.S.

RovAL Photographic Society, at S — Annual General Meeting.

RovAL Victoria Hall, at S.— A Visit to Russia: Smith Woodward.

RovAL Horticultural SociKTV, at ^.—Annual Genetal Meeiint;.

Federated Institution of Mining Engineers.— Meeting at Birming-
ham.

RovAL Asiatic Socirrv, at 3.

RovAL Mbdical and Chirl'rgical Society, at S.30.

Ko\al Colonial Imstititte. at S.

li^ED.VESDAy, February I?.

SociRTV OF Arts, at 8— Light Railways : W. M. Acworth.

Sanitary Institute, at 8. — Do* Methods of Sanitation: Dr. George
Vivian Poorc.

Pharmale'Jtical Society, at S.30.

THURSDAy, Fei.ruarv m.

Rjtal Sociktv, at 4 yy.

KoVAL Institution, at 3.— Meteorites : L. Fletcher, F.R.S.

Institution op Electrical ENGiNEKRS.at 8.— OnRevcr-iible Regenera-
tive Armatures, and Short Air Space Dynamos: W. B. Saycrs.

Society of Antiquaries, at 8.30

MATK3MATICAL SOCIETY, at 8.— Notet On the (Theory of Groups of
Finite Order, III. and IV. : Prof. W. Burnside, F.R.S.
FRIDAY^ February 15.

RovAL Institution, ai 9.— Mountaineering: Clinton T. Dent.

Geological Society, at 3.— Annual General Meeting.

Quekktt MiCKOsroi'iCAL Club, at S. — Annual General Meeting.

Epidbmiolocical Society, ac 8.— Dr. Atkinson, of Hong Kong.

BOOKS. PAMPHLET, and SERIALS RECEIVED.

Books. — Good Ri-ading about many Books (Unwin) — I,a Pr.ititiue du
Tcintwcier: J. Gaiv;on, ionic i and jiParis, Gaulhie^-ViIlar^). — SIusacI
Culture and the Ban Supply : W. L. Caldcrwood (MacmiUan). — Lchrbuch
dcr Algebra: Prof. H. Weher, Erster Band (Brannschweip, Vicwijj). —
Sea and Land: Prof- N. S. Shaler (Smith, Elder), — Steam and the Marine
Steam Engine: J. Veo (Macmillan).— N. S. W. Report of the Minister of
Public Instruction for the Year 1832 (Sydney). — Proceedings of the Inter-
national Conference rn Aerial Navigation held in Chicago. August i to ^,
tS93 (New York, Amcrhitn fCng^inccr^ &c.) — Progressof Science: J. 1.
Marmcry (Chapman and Hall).

Pa.mpiilf.t.- Eludes Climaio'ociques : A. Lancaster (Bruxelles).

Serials.— Century Magazine, February (Unwin).— C> niemporary Re-
view, February (Nbistfr) — A«clejiiad, No. 42, Vol. xl. (Longmans).—
Bulletin de I'Aradiimie Royale acs Sciences de Belgiitue, No 12. tome 38
(Bruxellcs). — Reliquary, &c., January (Brmro^c).— Natiunal Review,
February (Arnold) — Zeit-^chrift fiir Physikalische Cheniie, xvi. Band, 1
Heft (Leipzig, Engelmann).—Geograf.hical Journal, February (Stanford).

CONTENTS. PAGE

Argoti 337

A Text. book of Botany. Tiy H. H. D 339

A New Popular Boolt on British Butterflies and

Moihs. Hv W. F. Kirby 339

I Our Book Shelf:—

! U.iumhancr : " Die Resultate der Aetimethode in der

\ krystallographisclien Forschung, aneiner Reihe von

kryslallisirten Korpcrn dargcslellt. (Ilhistialed) . 340
Fowler: " Summer Studies o( Hirds and Hoiks " . . 341
Withcrby : " Forest Birds : their Haunts and Habits " 341
Letters to the Editor: —

On Ihe Age of the Karth.— Prof. John Perry,

I F.R.S. 341

I Oceanic Temperalurci al Different Depths. (With

' Z>/fl!;>-fl«;.)— Captain W.J. L.Whaiton, F.R.S. 342

j The liird-Winged Butterflies of the East.— Robert

H. F. Rippon 343

Thirst I'^ndurance in some Vertebrates. — Prof. S.

Carman 343

Kliclroscopcs in Lecture.- J. Reginald Ashworth 343
Snake Cannibalism. — Baron C. K. Obten Sacken 343

Pierre Ducbartre. By H • 344

Notes 344

Our Astronomical Column : —

New Stars and Nebul.x 347

The Dcsigna'ion of Comrts 347

The New Constituent of the Atmosphere. liy Lord
Rayleigh, Sec. R.S., and Prof. William Ramsay,

F.K.S 347

On the Spectra of Argon. By William Crookes,

F.R.S 3S4

The Liquefaction and Solidification of Argon. By

Prof. K Olszewski ZSS

University and Educational Intelligence 356

Scientific Serials 356

Societies and Academies 357

Diary of Societies 360

Uooki, Pampnlet, and Serials Received 360

NA TURE

?6i

THURSDAY, FEBRUARY 14, 1S95.

ELECTRIC OSCILLATIONS.
Les Oscillations ]-'.lcctriques. Par H. Poincarc, Membre
de rinstitut, Redigees par M. Ch. Maurain. (Paris :
Georges Carrd, 1894.)

WE have already noticed at some length M. Poin-
card's works on Electricity et Optique, and given
an account of his views regarding Maxwell's theories,
and his mode of presenting the subject in the light of
Hertz's researches. The present work discusses more
particularly the subject of Electric Oscillations, and
includes comparatively little of the more abstract treat-
ment of electrical theory to be found in the others. We
have in it a veiy instructive and well-timed n'stinn'
of a good deal of the later work on the subject, with
mathematical investigations of many points arising in
connection with the various experimental researches
referred to, which are of great value.

In a short preliminary statement of the theory under-
lying the Hertzian e.xpcriments, M. Poincarc' adopts, to
a certain ettent, the mode of presentation used by Hertz
himself. The two reciprocal sets of equations also made
by Heaviiide the starting-point of his researches, and
called by him the circuital equations, are made by
Hertz the basis of everything. Thus if L, M, N, X, Y, Z
be the components of the magnetic and electric forces,
^l and f the " coefficients of magnetic and electric induc-
tion,'' and A the reciprocal of the velocity of light, the
equations are

/aL aM ^^xi^T- 3Y ax az aY_a>:\

\bt' Hi' ilt) \by ds dz dx' d.v By)'

n. t sx ,, „^ \ /dM. a.v

&c.

, a^ dy

where u, v, \v are the components of conduction current
at .r,/, .?. When ?<, 7^, a' = o, one set of equations can
thus be formed from the other set by interchange of
L, M, N with X, Y, Z, and fi with -6. The electric
energy is f (X--|-Y-+Z-)/ St, and the magnetic energy
fi (L--|-M-+N-)'87r, each taken per unit of volume of the
medium.

The units of force are so chosen that /i and f are both
unity for vacuum, that is, for ether. Hence the intro-
duction of A m the equations above. It is required to
make the dimensions of both sides alike. We must con-
fess that we much prefer the idea contained, though not
clearly expressed, in Maxwell's treatise, of regard-
ing jjL and Iv as quantities dependent on the physical
properties of the medium, and such that the velocity
of light in the medium is i \/ /i K. There can be no
question of the enormous advantage of thus proceeding,
it avoids the obvious absurdity of giving in a general
system of measurement founded on the units of length,
mass, and time, two different sets of dimensions to the
same quantity according as it is measured electro-
statically or electromagnetically. Further, if this were
recognised, the serious difficulty which besets students,
when they find that what is defined or explained as a
mere ratio is unity, or the reciprocal of the square of the
velocity of light, according to the system of units adopted,
would entirely disappear. The discussion which took
NO. J 3 20. VOL. 51]

place in 1882 regarding the dimensions of magnetic pole
in electrostatic units, gave illustrations of the confusion
and misconception to which neglect of the dimensional
relation between /i and K can give rise in the mind of
even a master of physical science.

Let ^i„,K„, or better, /i,,,*,,, be the inductive capacities
( magnetic and electric) of ether, ja,K, those of any other
substance, then /x >i„, kk,-, will be the magnetic and
electric permeabilities of the medium, and will be mere
ratios. The magnetic permeability will then be as
Lord Kelvin originally defined it, the ratio of two magnetic
forces, of the magnetic force defined electromagnetically
(in a crevasse across the direction of magnetisation) to
the magnetic force according to the polar definition (in
a narrow cylindrical hollow parallel to the magnetisation),
and our ideas will no longer be liable to obfuscation in an
important fundamental matter.

M. Poincarc derives the second set of equations stated
above from the first set and the principle of conservation
of energy, using for the total energy per unit of volume
the sum of the expressions quoted above. The theoretical
basis consists thus of (i) the experimental fact that the
line-integral of electric force round a circuit is equal to
the time-rate of variation of the total magnetic induction
through the circuit, which gives the first set of equations :
(2) the expressions for the magnetic and electric energies;
and (3) the theorem that the work spent in heat per unit
of volume per unit of time is 'X!i-\-\'v-\-Z7t.'. The ex-
pressions for the energies are thus taken as fundamental.
The result does not, however, depend on zny supposition
as to exact localisation of the energy ; all that is involved
is the expression of the energy as an integral extended
through the whole field.

This is not the same as the process of Hertz, and it is
not clear that it possesses any advantage over that
method. In fact, Hertz's foundation is the two sets of
reciprocal equations, which are first postulated, then
shown to be consistent with observed phenomena. Thus
the whole structure rests on the equations, and Hertz is
but little, if at all, concerned with the dynamical explan-
ation of electromagnetic phenomena. This, on the
other hand. Maxwell is continually ; and one of the
most remarkable chapters of his book is that in
which he applies the method of Lagrange to give a
dynamical basis to the theory of induction and electro-
magnetic action. This was a natural outcome of the
other process, which he followed, of establishing his
equations as far as possible directly from the experi-
mental facts, and connecting them by a strong web of
dyn;imical theory. It does not seem likely, moreover,
that the minds of many of those who are eagerly seeking
for some more intimate knowledge of electromagnetic
action will be content with anything but a dynamical
explanation of electrical phenomena, and one which shall
elucidate, in some measure at least, the relation of the
ether to ordinary matter, and the reason for the
existence of the ponderomotive forces exerted in the
electromagnetic field.

In chapter iii. M. Poincarc proceeds to the theoretical
study of Hertzian oscillations, and discusses in the first
instance the solution of the differential equations for the
case of conductors situated in a dielectric. The first
part of this does not calf for special remark. X is taken

R

362

NATURE

[Fkbruarv 14, 1895

in the ordinary way as the real part of (B — i C)<^f'
where » = s' - • , and p = g-iy. The value of / is here
misprinted y-\-iq. The author then proceeds to find
solutiins for the case of an indefinitely extended
dielectric, and throwing the equations into the form

that is introducing the vector-potential, he goes on to
solve the resulting equations for X, Y, Z. Two solutions
are obtained of the form

f = - A \[^'^dxdyd=

where («) may have either of the values u', u' , given by
li -/ (jr'.y, z\ t), u = f {y,y, z, t - Ar). Here u' is
the value of the ^--component of the current at the point
(y.y, s") at time /, u" the value of the same component
at the same point at a time previous by the interval
required for the lij;ht to travel from (.»', j, z) to {x' , y' , s'),
r being the distance between these two points. The j
latter solution is, of course, adapted to the case of pro-
pagation in space with velocity i. A. It is exemplified by
application to the complete solution of Lodge's spherical
vibrator. This, in the assumed absence of radia'.ion of
energy and frictional damping out of the electrical vibra-
tion, may be regarded, for points external to the sphere, as
simply a time-periodic electric doublet; for its electrifica-
tion may be imagined produced by the relative displace-
ment through a small distance of two uniform sphcrica
volume distributions, each of which acts as if its whole
charge were situated at its centre. But the existence of
radiation very materially afi"ccts the result, for if r be the
distance of any point from the centre of the vibrator, a
the radius of the sphere, ^ a function which gives the
electric forces by the equations

X = a-y^bx^z, Y = d^^jfldySz,
Z = - A=a>/a/- + d^-^/3z\

the direction of the axis of the vibrator being that of r
then

n,= \Se e cos -_^V " A^

rlta - t\ia\

■JfZe e

- SI'C' - A^)

This expressio.1 is interesting as showing exactly the
damping due to radiation in this case ; that due to fric-
tional generation of heat is neglected. As i/A is the
velocity of lij,'ht, it will be seen that the radiation damping
is exceedingly rapid. Thii illustrates the difficulty of
" maintaining " electric oscillations ; and has an important
blaring on the interpretation of results obtained with-
resonators which are damped slowly as compared with
the exciters.

Of course, the damping in complicated cases can be
found when the total flow of energy through a spherical
surface of large radius, surrounding the vibrator, can be
computed by Poynttng's theorem. Thus it is possible to
construct a more accurate solution for points distant from
the vibrator, than that given by the supposition of no
damping, by thu* calculating approximately the expon-
ential factor, and we can go on by successive approxima-
tion if need be.

The results obtained by Hen with regard to the period
and the damping out of the vibrations of his exciter were
NO. 1320. VOL. 51]

tested, of course, by his resonator ; and we have, in
chapter iv. of M. Poincaro's work, an excellent account
of the mathematics of resonince, so far as here required,
and of the propagation of electric waves along wires,
illustrated by reference to the experiments of Sarasin and
De la Rive, Blondlot, and others. Many of these have
reference to the variation of the current with distance
from the end of the wire, at which, of course, reflections
took place. The theory, for example, of Mr. D. E. Jone>
experiments, in which a thermo-electric couple was usctl
to measure the heating effect at different distances from
the end of a long wire, is worked out ; and the results,
when compared with those of the experiments, are found
to agree.

Chapters follow on Propagation in Air, and Applica-
tions of Theory. In the latter, M. Poincarc refers, among
other things, to the results of the very important
experiments of Bjerknes, on waves received by re-
sonators of ditil'erent metals ; that is, their difterent rates
of damping, and the depths to which the currents
penetrate into the metal as measured by the thickness
(to take an example) of copper, which must be deposited
on an iron resonator in order that it may behave like
one of solid copper.

These three chapters have a very important bearing on
the question of multiple resonince, to which M. Poincare
has himself devoted special attention, and form, perhaps,
the most valuable part of the work.

Lastly, the book deals with such applications of
electrical oscillations as the determination of specific
inductive capacities, the reflection and refraction of
electric waves, and ends with a study of Hertz's
'• Memoir on the Fund.imental l-'qu.itions of Electro-
dynamics for Moving Bodies."

The mathematical discussions are, as we liave indi-
cated, throughout lucid and very frequently elegant.
The facility with which an app.\rently intractable
problem is taken hold of, and a few more or less
elementary considerations made to yield an approximate
solution or result, is very remarkable. We could have
wished for a somewhat mote physical treatment of the
subject ; but to those whose physical ideas have had some
training with regard to these matters, M. Poincarc's trea-
tise cannot but be ofgre.it service, as supplying what no
doubt was its obj:cl, a review of the princip.il results
obtained in this field of research compared with theory,
as far as possible by the only sure test, that of calculation.

A. Gr.W.

r//E BOOK OF THE ROSE.
The Book of the Rose. By the Rev. A. Eoster-Melliar,
M.A., Rector of Sproughton, Sufl'olk. Pp. 33'). 29
illustrations. (London: Macmillan and Co., 1894.)

MR. MELLIAR is well known among horticulturists
as a successful grower and exhibitor of roses, and
his book is what he wished it to be — the rose considered
as a flower, with full dct.iils for its practical culture for
amateurs, from the beginning to the end. Art is his text
all through. He has very little to say about the botany
of the rose, its geographical distribution, the origin of
the numerous races of garden roses as distinguished from
their wild progenitors, the fourteen chapters of his book

February 14, 1895]

NA TURK

36:

being devoted to such matters as soil, manure, planting,
pruning, propagating, and exhibiting. For the cultivator
the book covers all the ground, and Mr. Melliar's in-
structions arc as clear, as thorough, and as trustworthy
.13 any budding " Rosarian " could desire. There are
already plenty of books about the rose, of which as miich
as this can be said, but there is still room for Mr. Melliar's.
Me writes mainly for the amateur grower of roses, and
strongly recommends his hobby to the country parsons
who are, he says, "all so poor, and likely to be poorer
still." The delights of the rose-grower are only ex-
perienced when he himself does all the work entailed in
tlie production of plants from cuttings, buds or seeds, to
the exhibition flowers. The genuineness of Mr. Melliar's
love for his hobby is seen in the following extract from
his book : —

" But if it was you alone who had found, chosen, and
grubbed out the [briar] stock from the hedge, or cut,
prepared, planted, and transplanted the briar or manetti
■ utting if no hand but yours had budded it, cared for
It in all stages, and finally cut and shown the Rose— then,
when perchance it is declared on all hands to be the
finest specimen of the variety ever shown, it must be an
ulditional pleasure to know that it is your Rose indeed,
lor that, a^ far as all human aid is concerned, you made
It yoursell."

If the bink has a fault, it is to be found in this treating
if the rose solely as a flower to be set on a tray at an
fshibition and win a prize. Mr. Melliar has something
of the narrowness of view of the old florist, for he sees
little beauty in roses which are not likely to win prizes.
He devotes thirty pages to instructions on exhibiting the
flowers. This chapter is interesting as showing how
much care and self-sacrifice are necessary to success in
the exhibition tent, the paper covers to protect the buds
from rain, wind, and sun, and the precautions necessary
even when the flowers are ready to pack in their prepared
mossy beds in boxes. In one very dry season, he says,
his mossed boxes had been kept in the shade and duly
watered, with the result that two huge slugs, each as big
as his thumb, concealed themselves in the moss, and
during the journey to the Crystal Palace regaled them-
selves on the roses !

Mr. Melliar speaks of several varieties of rose that
show deterioration since they were first introduced, or
" sent out," as the raisers express it. These fine varieties
of rose are always propagated from grafts or cuttings,
and deterioration is therefore unlikely. The same state-
ment has been made with regard to apples, pears, and
other fruits, which are multiplied in the same way as
roses, but they have never been substantiated.

Until within the last thirty years or so, all the best
garden n ses were raised by continental growers, the
belief being t'lat they could not be produced in England.
The same belief prevailed until recently with regard to
chrysanthemums. It is therefore a pleasant suriirise to
see that of the 144 varieties of the Hybrid Perpetual
section of roses, selected by Mr. Melliar as the choicest
and best, no less than sixty of them were raised in
England, ar.d that the two best H.P. roses known, viz.
" Her Majesty " and "Mrs. J. Laing," were raised by the
ate Mr. Bennett in Surrey. To these I would add a third,
namely, " Grace Darling," also raised by Mr. Bennett, and
NO. 1 pO, VOL. 51]

which, although not an exhibition rose, is yet one of the
most beautiful of all in the garden. Its only rival is
" Gloire de Dijon,'' raised in France forty years ago, and
of which Dean Hole, prince of rosarians said, " Were I
condemned to have but one rose for the rest of my life
I should ask, before leaving the dock, to be presented
with a strong plant of ' Gloire dc Dijon.' ''

A book which deals chiefly with exhibition roses can
scarcely be considered to justify its title, " The Book of
the Rose," because to all but a very small section of
gardeners the rose appeals with greatest force when
seen as a naturally grown bush in the garden. The close
pruning and other rigorous methods of the grower-
exhibitor are suggestive of ear-cropping for dogs, and
comb-cutting for cocks, disfiguring, for a special purpose,
otherwise beautiful objects. Mr. Melliar has very little
to say for the many beautiful single-flowered roses which
are now coming rapidly into favour with gardeners, and
whose flowers are often as lovely as the highest floral
art could wish. Many of the perfect exhibition roses
are just about as attractive in form and colour as a red-
cabbage. The hybrids raised by Lord Penzance from
the sweetbriar crossed with garden roses, are exceedingly
beautiful, so too are the forms of the Japanese Rosa
rugosa, A', viultiflora, li. bracteata, R. indica, &c.

It is becoming a too common practice amongst
professional gardeners to set about crossing beautiful
species of plants, roses included, with a view to
doubling or otherwise altering the form, or " im-
proving " the colour of the flowers, to satisfy some
absurd ideal, the consequence often being a con-
siderable loss from the point of view of true art.
We owe the garden roses of the present time to the
breeders of florists' flowers, and are duly thankful. At the
same time we would prefer to keep the best of the single-
flowered roses just as they are. Mr. Melliar does not
agree with those who look upon the rose as a decorative
plant for the garden, but only as a means whereby he
may obtain glorious roses. For me, the best tray of
exhibition roses ever produced has infinitely less charm
than a bed of yellow Banksian roses, or even a tangled
mass of sweetbriar when covered with flowers. How-
ever, Mr. Melliar's book will teach any one how to grow
good rose flowers, and there are thousands who would
find pleasure in rose-growing by reading and following
his directions. W.

OUR BOOK SHELF.
Vlndustrie des Araneina. By Woldemar Wagner.

(.St. Petersbourg : L'Academie Imperiale des Sciences,

1894.)
This work may be divided into two sections: (i) the
desciipiiiins of the cocoons, nests, &c., of the commoner
kind> of Russian spiders ; and (2) the conclusions re-
specting the evoluti(m of instincts and the classification
of the species, to be drawn (roni the data thus established.

Wa>;ner recognises four kinds of silken structures —
namely, the snare, the retreat, the nest, and the cocoon.
About the first of these but little is said. The remaining
three, however, are discussed in considerable detail, and
to the question as to whether these structures are of
great :axonomic value, M. Wagner gives an unhesitating
and most positive affirmative reply. It is unfortunately
impossible within the liriiits of a short notice to criticise

>64

NATURE

[Februakv 14, 1895

closely his arguments ; but that they are worthy of the
deepest attention, will be realised by all arachnologists
who are acquainted with M. Wagner's previous works.

Perhaps the highest praise that can be bestowed upon
this work, is to say that, even when stripped of its
theories, it quite reaches the high standard of excellence
attained by M. Wagner's previous papers, and that the
great value of the theoretical part lies in the fact that

the key to all problems is sought in the hypothesis of
evolution by means of Natural Selection.

The memoir is admirably illustrated with ten litho-
graphed plates, of which eight are coloured, and, in
addition, with two hundred and fifty-two diagrams in the
text. The figure we here select for reproduction, to give
an indication of the nature of the rest, represents the
female of Ocyale mirabilis carrying her cocoon.

R. 1. 1'.
EUmentarY Practical Chemistry, Inorganic and Orj^anic.

ByJ. T. Hewitt, M.A., D.Sc, Ph.D., F.C.S., and F.

G. Pope. Pp. 4;. (London : Whittaker and Co.)
.\l.THOLGH the authors of this small book have confined
themselves to such parts of elementary c|ualitalive
analysis as find a place in .Stage I. of the Science and
.■\rt Department Syllabus, neither in general plan nor
in details of treatment does the book possess any
educational advantage over its many competitors. A
mere recital of reactions cannot be considered as
" Elementary Practical Chemistry." Surely it is possible
to present even the array of facts utilised in analysis in
such a manner as to comply with the fundamental re-
quirements necessary to be fulfilled by all educational
works designed for young students of science. The pro- 1
duction of compilations of the present type will probably
cease to exist when the new regulations for Organised
Science Schools come into force. We may then, perhaps,
look for the production of really philosophical text-books
arranged on sound educational lines, and yet calculated
to minimise the very real difficulties encountered by the
beginner. Putting aside these fundamental considera-
tions, it is only just to say that the authors have brought
together a strictly limited set of reactions with lew
positive inaccuracies.

How to Live in Tropical Africa. ByJ. Murray, M.D.

Pp. 252. (London : George Philip and Son, 1895.)
So far as literary merit is concerned, this is a poor book.
The text is disjointed, it is too full of unnecessary
quotations, and there is too much tautology. liut if only
the subject-matter is considered, the verdict is that the
book is a trustworthy guide to tropical hygiene, and a
useful manual on the cause, prevention, and cure of
malarial fevers. The importance of such a handy volume
to emigrants and visitors to Africa can hardly be over-
stated. And as the book is the outcome of medical
experience, it possesses exceptional value.
VO I 3 JO, VOL. 5 I ]

LETTERS TO THE EDITOR.

[ The Editor docs not hoi J himstlf rtsponsibU for opinions t.\-
pressed ty his corresponJenls. Ntilher can he undertake
to return, or to correspond with the writers of, rejected
manuscripts intended for this or any other part of Nature.
No notice is taken of anonymous communications. ]

The Liquefaction of Gases.

Prof. Olszewski's letter in Nature of January 10 is a more
seiipus mailer ihan a claim for pricrily. The letier ch.-»rges
Pm(. Dewar wiih allowing the impresMon to go abroad that he
has carried out much original research into the methods of
liquefying ihe more permanent gases, and the properties of the
liquids produced ; whereas, according lo Prof. Olszewski, most
of Prof. Dewar's experiments have been merely repetitions of
work ('one by others.

In his brief coir.iminicalion lo Nature (January 10), Prof.
Dewar has been too modest either to defend himself or to meet
his opponeni. Forlunaiely, he makes one definiie statement : —
'A reference to ihe /Viheedi n^s of ihe Royal Institulion
between the years 187S and 1893 will be sufficient to remove
the suegestion thai the apparatus I use has been copied from
the Cracovie HuUelin of 1890. "

I have followed Prof. Dewar's recommendation, and mace
references to \):\e Prcceediiij^s o\ the Royal Insiituiion. In his
lecture at Ihe Ro>al Institulion onjunc 13, 18S4 (Proc. A". /.,
xi. 14S), Prof. Dewar relers to Me-srs. Ol-zewski and
Wroblewski as having " recently made such a spk-ndid success
in ihe produciion and maintenance of low temperaiure." He
desciibes and figures an apparatus which is asligtitly modilied
form of that o( the Polish professors, which in turn was derived
from the api aratus of Caillelel ; and he says: "Provided a
supply ol liquid ethylene can be had, there is no difficulty in
repealing all ihe experiments nf the Russian observers. ' No
claim is made here to originality in the essentials of the
apparatus, ror in the expeiinients performed. The
apparatus referred lo by Prof. Llewar in his It dure
ol June, 1S84, was used by Prol. Olszewski in 1SS3,
and was improved by him in 1^84; in 18S7 the ap-
paralui- was made capable ol liquefying ONygen and other g.ises
in coni-idcial'le quaniiiies at the ordinary atmospheric pressure
(see Olszewski, I'hi!. Mag. February 1895, 189-190). In 1S90
ihe apparatus was so improved that from joto loocc. of liquid
ox>gtn could be produied by it (see Olszewski, Phil. Mag.
February 1895. 192-193). Pri f. Ol.szewski siaies (Nature,
January 10) thai a description of this improved ap| .-xralus was
sent 10 Piol. Dewar. A year after this, on June 26, 1891,
Prof. Dewar delivered a discourse on Faraday's work at the
Rojal Institution. The published al siract of this lecture (/"/w.
K. J. xiii. 481) contains a phoiograph of the pumps and engines
j used in ihe laloiatoiy ol the Royal Institution, and a photo
graph of the arrangement of ihe apparatus on the lecture table ;
bill it is impossible to make out the details of the apparatus
liom these pholoj;raphs. So far as can be judged from the
Proceedings of the Royal Institution, Prof. Dewar did not show
larne quanlitics of liquid oxjgcn, nitrogen, cr air in his
lectures until June 10, 1892, when be placed before his audience
a pint of liquid oxygen. Two years before ihis Prof. Olszewski
had obtained 100 c.c. of liquid oxygen, and he tells us in his
letter to Naiuke (lanuary io)ihai 200 c.c. of this liquid were
prepared and exhibited by him in July 1891. A pint is 1111-
doubicdly more than 2coc.c., but unless one does something
wilh the larger qunnlity wlii.h cannot be done equally well with
the smaller, nothing is ganed by conducting ihe manufacture
on the large scale.

I can find no other mention of the apparatus used at the
Ro)al Institution for liquefying large quaniitiesof gases. There
is indeed no accurate ilescription in the Proceedings ol that
Institulion of the apparatus used by Prof. Dewar. if Prof.
Dewar has made markcil impiovcmenls in any essential parts
o( Prof. Olszewski's apparatus, why has he not pulilished an
accurate description of these impiovemtnis in some recognised
scieniific journal ?

A relerence lo the Proceedings of the Royal Institution is
Ihm sufficient, not loreniove, bui 10 strengthen, " the suggestion
that the apparaius I [Prof. D<wai] use, has been copied Ironi
lie Cractvie liullelm ol 1890," or ai least ihat it has been
hniri'tted from detciiptions of apparatus devised by Prof.
Olizwli.

Februarv 14, 1895 J

NATURE

365

Every one must admire, and praise the skill which
fashioned, the vacuum receiver; for storing and experimenting
with comparatively large quantities of liq lid oxygen and air,
which Prof. Dewar used in public for the first tim? on
January 20, 1893, so far as can be gathered from the Proued-
iiii^i of the Royal Instituiion (see Proi. P. I. xiv. i.) The
f)llowing sentences occur in the published abstract of Prof.
Dewar'-i lecture on that date: "The prosecution of research
a temperatures approaching the zero of absolute temperature
is attended with difficulties and dangers of no ordinary kind.
Hai'iiig no recorded experience to guide us in conducting such
investigations, the best instruments and methods of working
have to be discovered." (The italics are mine.) {Prflc. R. f.
xiv. I.) Now, in June 1890, that is two and a half years before
Prof Dewar made the statement I have quoted, Prof. Olszewski
was able to say: "My new apparatus excludes the incon-
veniences of the former one, and renders it possible to preserve
the liquid oxygen a longer time under the ordinary atmospheric
pressure." And ag^in : "Thus was solved the problem of
liquefying considerable quantities of oxygen wi'hout the slightest
danger." (See Olszewski, Phi/. Alug. Fehruaiy 1895, 193-3.)
l.very reader of Prof Olszewski's papsr will agree that these
statements are justified. Moreover, in October 1S91, that is,
fifteen months before Prof. D;war diiclared there was " no re-
corded experience to guide us in condujlinij such investigations,"
Prof Olszewski (in conjunction with M. Wiikowskij described a
method for not only sioring. but also experimenting with,
considerable cjuantities of liquid oxygen {Cracovic Bulletin,
October 1S91). So far back .is 1887 he published, in
ll'icde/nann's Annalen (xxxi. 58), a full ac».ount of methods for
'ietermiiiin^ ihe densities of liquid oxygen, nitrogen, and marsh
1,'as. In 1887, al-c, he determined the boiling p jint of liquid
ozone, and he began his measurements of the abs')r(ition
spectra of liquid oxygen and air (IViedcmaiin's Annalen,
xxxiii. 570) ; and in 1891 he published further measurements of
the absorption spec'rum, an I the refiactive index, of lM|iid
oxygen (iliid. xlii. 663 ; see also Phil. Mag. February 1895,
197-9, and 206-8.)

It is ju-t these jiropcrties. namely, the optical properties, of
liquid oxygen which had been elaburaiuiy studic 1 by P.of.
Olszewski f 0111 188710 1891 that are largely dwelt on by Prof.
Dewar in his discourse of January 1893 ; and it is the ilkntrai ion
of these piopcrties that is prefaced by the remark, there is
"no recorded expeiicnce to guide us in conducting such inves-
tigaiions."

On January 20, 1893 (Proc. R. I. xiv. 10) Prof. Dewar said
that liqiiiil oxygen is " the most convenient substance to use (or
the production of tcmpeiatures about -20o''C. Liquid nitrogen,
carbonic oxide, or air can conveniently be made at the ordinary
atmospheric pressure, provided ihey are brought into a vessel
cooled by liquid oxygen boiling under the preisure of about
half an inch of mercury." It is interesting to compare with
this Prof. Olszewski's words published in June 1890 (C;ac. Bull.:
I quote from the translation in Phil. Mug February 1895, 192) :
" I proved long ago [Com//, rend. c. 350 (iS85<J that liquid
• 'xygen is the best cooling agent ; for it easily gives thetempera-
;ure of - 21 1^'5 C. if the pressure is lowered 9 mm. of mercury,
and it does not fieeze even at the pressure of 4 mm." It may
he said lint the simila'ity between these statements is merely a
coincidence. Perhaps it is, Neveith-less, Prof. Dewar's
statement conveys the impression that he was the first experi-
menter to employ liquid oxygen for obtaining, and maintaining,
very low temperatures. Another of Prof. Dewar's statmients
which imply more than they express, occurs in his lecture of
June 10, 1S92 [Proc. R. /., xiii. 695) : " He hoped that even-
ing to go several steps further, ana to show liquid air, and to
render visible some of its more extraordinary properties."
Remembering that air had been liquefied by Piof Olszewski at
least eight years befoie the lecture whertin this statement occurs
was delivered, one must regret that Prof, Dewar did not choose
words which should hive made it impossible for the English
public to suppose "that the liquefaction of oxygen and oiher
so-called permanent gasi-s was ach eved for the first time by
[him] " (See Prof. Olszewski's letter in Naturi: of January
10).

Not only docs Prof Olszewski claim to hive devised the
methods, and constructe 1 the apparatus, for liquefying con-
siderable quantities of the m ^re permanent gises, but he also
asserts that most of the exieriments on the properties of these
liquefied gases which have been performed by Prof. Dewar are

NO. 1320. VOL. 51]

only repetitions, on a larger scale, of work done by others.
What, then, are these experiments?

Measurements of the refractive index of liquid oxygen,
for the sodium light, and also of the absorption spectrum
of liquid oxygen, were published by Profs. Liveing and
Dewar in August 1S92 (Phil. Mag. (5) xxxiv. 205 ; see
also Dewar in Proc. R. I., June 10, 1892 ; and Liveing
and Dewar in Phil. Mag. for August 1894). The re-
fractive index of liquid oxygen had been measured, and deter-
minations of the absorpti m spectrum had been made, by
Olszewski and Wiikowski in October 1891, and these measure-
ments were the complement of work begun, and published, by
Prof. Olszewski in 18S7 {U'iedcfnann's Annalen, xxxiii. 570.
See Olszewski in Phil. Mag., February 1895, 197-9). It is true
that preliminary experiments on the absorption spectrum of
liquid oxygen had been made by Profs. Liveing and Dewar in
1889. In their paper in Proc. R. S., June 6, 1889, they say : —
" We have observed repeatedly the absorption of liquid oxygen
in thicknesses of 8 and 12 mm. Our observations confirm
those of Olszewski."

On December 10, 1891, Prof. Dewar announced, in a note
to the President of the Royal Society, that liquid oxygen is
attracted by the poles of a magnet. This note was followed by
another, on December 17, 1891, saying that liquid ozone was
also attracted by the poles of a magnet. These detached, but
inieres'.ing, experiments, which followed up work done by
Faraday many years ago, must be placed to the credit of the
Fullerian Professor at the Royal Institution.

A paper published in Phil. Afag. (5) xxxiv. 326 (1892) by
Dewar and Fleming, on the electrical resistances of metals and
other bodies at very low temperatures, contains the only piece
of exact investigation to which Prof Dewar's name is attached
wherein liquid oxygen or air is used as an instrument of re-
search, with the exception of the measurements of the optical
properties of liquid oxygen, which have been shown to be
mainly repetitions of the work of Olszewski and Witkowski,
This research carries on and supplements earlier work done
by Cailletet and Bouty, and by Wroblewski {Comptes rendus,
ci. 161 (1885),

A lew observations have been made by Prof Dewar on the
phosphorescence ol various substances at the temperature of
boiling oxygen, and on the cessation of chemical action, and
the continuance of photographic action, at the same temperature
(see Proc. R.I. June 26, l8gi and June 10, 1892, also January
20, 1893; also Prcc. Royal Soc. .A-pril 19, 1894, and Proc.
Chcm. Soc. June 28, 1894). The subject of chemical action at
very low temperatures was investigated by Pictet in May and
November 1S92 (Comptes lendus, cxiv. 1245 ; cxv. 814) in a
much more exhaustive way than has been done by Dewar, who
has only touched the Iringe of the matter (compare also
Olszewski, Phil. Mug. Februaiy 1895, 208-9). The observa-
tions on the sensitiveness of the Eastman film at very low
temperatures are ii.tercsting ; but, so far as it has been pub-
lished, the work is too slight to present material for detailed
criticisms ; and the same may justly be said of the lecture
illustrations of phosphorescence at low temperatures. It may
be remarked that Prof Dewar's paper on photographic action
at low tempera' uies has appeared only in ihe Proceedings, not
in the Transactions, of the Chemical .Society.

Prof Olszewski's work on the properties of liquefied gases
was begun, and accounts of his accurate expenmtnls were
published in recognised scientific journals, long before Prof.
Dewar's expeiiments were heard of The work of the Polish
I'lofessor is being continued in the same exact, modest, and
scientific manner (see his paper on the optical dispersion of
liquid oxygen in Ciacovie Bulletin, July 1894, noticed in /'/;//.
■ Uag., February 1895, 208 ; and his determinations of the boil-
ing and freezing points, and other constants, of argon communi-
cated to the Royal Society, January 31. 1895).

It seems to me that I'rol. Olszewski has established a case
which demands the instant and serious consideration of those
who are truly interested in the advance of science, and are
jealous of the good name of the scientific men of this country.

Cambridge, February 7. M. M. Pattisox Muir.

ThI'; object of the communications on the liquefaction of
g.ases, which have recently appeared in Naiure and the
Phitosofhical Magazine, is to depreciate the work of Cailletet
and Pictet, to smother away the first-class work of the deceased

366

NA TURK

[February 14, 189-

WroblewsWi ; to annihilate myself, and thereby lo magnify the
cUums for originilily of Pr.jf. Olszew ki. In spite of the mis-
takei inevitable to pioneer-, the work of Caillelei and Piciet
must aUay; be credited wiih originating research in this depart-
ment. To show my apprecatua of such invesiigation, and
to give it a wide publicity in the year 187S, a Friday
evening iddrcsi was devoted 10 the work ol Caillctet and
Pictel, during the course of which 1 sho*ei for the first time
in this country the working of the Cailleiel apparatus. Simi-
larly, in the year 18S4, an ad Iress was given on ihe woik of
Wroblewski and Olszewski, in ihe course of which I illustialed
for the first time in public the l.quefaciion cf oxygen and air,
showing the boiling point, &c., by means of a simple form
of apparata* which did not involve the use of the Cailleiet
pump as employed br these experimenters. To deliver a lec-
ture on the work of 01 her people is generally considered a
mark of honour, and as usefully diffusing a knowledge of the
same. The cii ic has for .-ome object omiited half the opening
sentence of this address, wliich runs as follows : —

"The t*o Russian chemist-, .M.M. Wroblewski and Olszewski,
who have recently made smh a splendid success in the proiluc-
tion and maintenance of low temp-rature, have u.ed m their
researches an enlarged form of the well-known Caillcei appa-
ratus ; but for the purpo-e of lecture demonstration, wliich
necessarily involves the projection on a screen ol the actions
taking place, the appara'us represented in ihe annexed wojdcut
15 more readily and quitkl) handled, and enabUscomparatively
large quantiiies of liquid ox)gen to be (.roduced."

The same tactics have lieen adopted of taking half a sentence
from another part of the a IJress, and leaving out the context.
The sentence to which I relet ran thus : —

" ProiiJtd a supply of bijuid ethylnii can be had, there is no
difficulty in refeatiug all the experiments of the Russian
observers ; but as this gas is trouliicsomc to make in quanliiy,
and cannot be bought like carbonic acid or nitrous oxide,
such expel iments necessitate a considerable sacrifice of time.
It was therefore with considerable saiisfaction iha, I observed
the production of liquid oxygen by the use of solid carbonic
acid, or, preferably, liquid nitrous oxide." _

Then follows a full description of how to use nitroiis oxide
with the apparatus in order to get liquid oxygen. Note the
disingenuous comment of the critic : " No claim is made here
to originality in the essentials of the apparatus, nor in the ex-
periments performed." It has never been the custom to make
public claims for originaluy, either in apparatus or experiment,
in ibe course of an address given at the Royal Institution.
lie proceeds to allege, "the apparatus referred to by
I'rof. Dewar in bis lecture of June, 1884, was used by
I'rof. OsMWski in 1883." On turning to the reference given,
1 find the following statement by Olszewski : "In 18S3, and
fjr several years following, I liquefied the gases in a strong glass
lube." According to this distortion of lad, the apparatus of
Andrews, CaiUetcl, Wroblewski, and Dewar are all the same,
because gas was liquefied in a glass tube. I challenge the pro-
duction of a refeience to an apparatus antecedent to the date of
this lecture in which liquid nitrous oxide had been used for the
production of liquid oxygen. But all this is ancient history ;
the real charge begins wuh the year 1890. Assuming that 1
had been the thief of I'rof. Olszewski's apparatus of 1S90, which
is alleged lo be the type used in the laraday Commemoration
Lecture of 1891, ^uha: explanation is forthcoming of the delay
of four yean in ventilalin); the question of priority and personal
grievance I H'hat his oicurred at the present juncture to pre
ctpilalc a crisis/ Can any one avoid coming to the conclu
tioo thai I'rof. Olszewski's contact with "Argon" explains
the iuddcn asiault upon my labours in the same field of
investigation. ...

If the critic had been a Iruttworthy person even to examine
into the published factn, he could have found a reference in ihe
Pro^eedtuf^s of the k'lyal Institution, between the )ears 1878
and 1893, that would have enlightened his ignorance, and
thereby prevented his reiterating I'lof. (Jlszewski's suggestion
that my large apparatus of 1891, which produced pints of
liquid oxygen, wa* copied or borrowed from a description in
the Cracovie liullctm for 1890. ...

Let us see what I'rof. 0.>zew-ki laid in that paper, cDtitled
"Tran*va«enicnt de Toxygenc liquide," June 1890 : —

" A flask (if wrought iron, five litres in cap.icily (such as is
utcd to hold liquid laibon dioxide), containing oxygen under a

NO. 1320, VOL. 51]

pres.sure of 80 aim., is joined by a narrow copper tube to the
upper end of a steel cylinder tested at a pressure of 200 at m.
This cylinder having a capacity of 30-100 cub. centim., accord-
ing to ihe quantity of oxygen which we wish to liquefy at a time,
is immersed in liquid ethylene, of which the tempcraiure may
easily be lowered to 140 c. by means of an air-pump. The
lower end of the cylinder is joined by a narrow cop^ier tube to
a little stopcock, through which the oxyijen, liquefied in the
cylinder, can be poured down into an open glass vessel, kept
cool by the surrounding air."

In o her words, replace the glass tube in'my apparatus of 1SS4
by a small steel cylinder, and attach to its lower end a narrow
copper tulie with a stopcock, and the O szewski apparatus of
1890 is produced (as a matter of fact, Piciet had used the same
principle in the year 1S7S). Now, on June tl, 1S86, I delivered
a lec'ure on " Kecent Researches on Meteorites," and the report
in the /"/vcVti/rV/iVof the Royal Institution contains a sectional
drawing of an apparatus solely construe ed of c ipper, to-
gether with a valve for drawing ofif iiqui 1 oxygen, en-
tiiely different in type from the cude plan Olszewski
adopted in 1890. I may mention tha' the p'an of the apparatus
was reproduced immediately afier the delivery of the lecture,
both in England and .\aierica. The section is confined to the
refrigerator, all the acce-sories of liquefied and compressed gas
bottles, compteision and exhaust g.iusjes, &c., having been
omitted. From this plan of the refrigeratir, any person so
desiring could increase its capacity so-a; to woik on a larger
scale. The drawing shows the apparatus arranged for the
special experiment of ejccing liquid oxygen into a vacuum
chamber, but it is clear the apparal us discharged as easily into an
open vessel. It ii not any isolated experiment thit is in dis-
pute, but the new foim of apparatus. The special object for
which liquid oxygen was in use in this lecture, was to cool a
piece of meteorite before insertion into an electric furnace. The
following extract fiom the lecture will explain how the subject
was introduced : —

" Meteorites, no doubt, have an exceedingly low temperature
before they enter the earth's atmosphere, and the q leslion had
been raised as to whit chemical reactions could take place under
such conditions. It resulted from Prof. Uewar's investigations
that at a temperature of about 130" C, liquid oxygen bad no
chemical action upon hydrogrn, potassium, sodium, phos
phoius, hydriodic acid or sulphydric acid. It would appear,
therefore, that as lli; absolute zero is approached, even the
strongest chemical affinities are inactive.

"The lecturer exhibited at work the apparatus by which he
had recently succeeded in solidifying oxygen. The apparatus
is illustiated in the accompanying diagram, where a copper
tube is seen passing through a vessel kept constantly full of ether
and solid carbonic acid ; ethylene is sent through this tube, and
is liquefied by the intense cold ; it is then conveyed by the
tube, through an india-rubber stopper, into the lower vessel ;
the outer one is filled with ether and solid carbonic acid. .V
continuous copper tube, about 45 feet long, conveying oxygen,
passes through the outer vessel, and then through that contain-
ing the liquid ethylene ; the Utter evaporates through the space
I between the two vessels, an 1 thus intense cold is produced,
whereby oxygen is liquefied in the tube to the extent
occasionally of 22 cubic centimetres at one time. The tempera-
ture ai which this is effected is about - 130° C., at a pressure of
75 atmospheres ; but less pressure will suffice. When lli;
oxygen is known to be liquid, by means of a g.iuge near the
oxygen inlet, the valve A is opened, and the liquid oxygen
rushes into a vacuum in the central gl.ass lube below ; some
liquid ethylene a' the bottom of the next tube outwards is also
caused to evaporate into a vacuum at the same moment, and
instantly some of the liquid oxygen in the central tub; becomes
solid, owing to Ihe inttiue cold of the double evaporation. The
outer glass vessel serves to keep moisture from settling on the
sides of the ethylene tube. By means of the electric lantern
and a lens, an image of this part of the apparaius w.u pro-
jected upon the screen, this being Ihe first time that the
experiment had been shown on a large scale in public.

" I'erfrnming this experiment, the temperature reached was a
little below 2Co' C, that is, only 50' or 70 above the absolute
zero of temperature, .".nd in the experiment about 5 lbs. of liquid
ethylene were employed."

This I declare to be the firsl apparatus made wholly of metal,
being an arrangemciit of copper coils, in which liquid oxygcii

February 14, 1895]

NATURE

367

was made and decarted or Iransferted from the vessel in which
1 was liquefied to another by means of a valve, and thereby
lendered capalile of use as a cooling agenr. In su|>port of ihis
as?eition, I call as witness Pro'. Charles Olszewski himself,
who states in the rhilosnphiial A/agazine, February 1895,
p. 189: "In 1SS3, and for several years following, I liquefied
the gases in a sirong glass tube." There is no sugce^ion made
that a steel cylinder and valve was used by Olszewski till the
yeir 1890. Whereas four years in advance I had u-ed a much
safer and I etiur form of apparatus, practically identical in prin-
ciple with that u-ed in Cracow in the year 1890. Have 1 ever
sugge led that Prof. Olszev/ski was aniicipated, or atiempied to
raite any question of piiority? Perhaps ihe critic will have
the audacity to say, in reply, this is no publicaiion, the J'lo-
<:'edings of the Koyal Intctiition, English and American science
f eriodicals, nt t 1 eing among-l the class of recognised scienlific
outnals. Well, if I am pleased to throw my bread upon the
waters, adopting the view that every truthfully recorded experi-
ment which appears in any journal associa'ed with my nau e is
public.iiion, suiely I should simply be conducting myself in the
*' too modest " way my critic commends.

As a specimen of the distortion of facts to prove another case
of priority that is claimed, I find that MM. Charles Olszewski
and Augusie Witkowski, Membres Correspondants, presenting
their memoir " Proiriees opiique de I'oxygene liquide," on
October 3, 1S92, and, on referring to the paper, it is dated July
15, 1892, and the (iillowmg footnote is added :

" Avant la publication cle notre comraanication, M^•. Liveing
et Dewar ont fait connaiire (Phil. Mag. Aout 1892), les
resultats de leurs rccherches sur la refraction des gaz liqucjiies."

Yet the crilic says our experiments were ' marniy repetitions
o( the work of Olszew.-ki and Witkowski." The garbled extracts
selected to make it appear that I have been guilty of mis-
represi ntation are all of the same kind. . . . Thus I am taken
to task for using the expression in the lecture on liquid air,
of 1S93 : ** Having no recorded experience to guide us in con-
ducting such investigations, the best instruments and methods
of working have to be discovered." The next sentence runs as
follows : " The necessity of devising some new kind of vessel
for storing and manipulating exceedingly volatile fluids like
liquid oxygen and liquid air, became apparent when the optical
properties of the boclies came under'examination. Apart alto-
gether from the rapid ebullition interfering with the experi-
menlal work, the fact that it did take place involved a great
additional cost in the conduct of experiments on the properties of
matter under such exceptional conditioasof temperaiure." What
can be said in defence of such glarin.^ misrepresentation of the
meaning of my words ? Mr. .\I. M. Pattison Miiir's demand for
^^ instant ami serious cottsiiieration" of his client's **case'' has
been quickly met. I trust the result will .... fit in with
his brief. James Dewar.

Koyal Institution, February 12.

[A few personal remarks in Prof. Dewar's letter have been
omitted, as they do not affect the points at issue. —
Ed. Nature.]

Vertebrate Segmentation.

Mr. H. G. Wells, in a recent number of Nati'rf, honours
my littie book by making it an example of a contravention of
what he regards as a principle of education. With that I have
no quarrel. But I must object to ihe insance he has chosen.
The sentences from wl ich he quotes refer to the phenomena of
segmentation common to coelomate tissues, and not to the
derivation of vertebrates from any invertebrate group. So far
from giving *'lhe impression almost in so many words — *cut
and dried,' and ready to be ca^t into the oven — that the verte-
brate type is merely a concentrated derivative (concertina
fashion) of the cfjeiopod type," I devote the chapter (xv.)
from which he has taken his quotations, to showing that the
earthworm ami the vertebrates merely belong to two out of the
many isolated groups; and at the end of the chapter (though
not in spaced type, as I did not consider the question of verte-
brate descent congruous with the aims of an elementary text-
book) I state that " the type common to the lowest members of
the groups of which the earthworm on the one hand, and the
vertebrates on the other, form the highest examples, is a simple
unsegmented ccvlomate animal."

P. Chalmers Mitchell.

The Black veined White Butterfly.

Mr. KiRtv, on p. 340 of your last issue, says (in criticism
of Mr. Furneaux) that this insect "would not frequent open
ground at a distance from trees." I suppose there are not now
many Englishmen who have taken it in this country ; and it
nay be worth while to record that the common on which my
brother and I used to find it tolerably abundant in the years
1S5 7-1859, was quite an open place, with no adjacent «ood,
and very little hedge timber. This common is about a mile
and a half to the west of Cardiff ; I passed it in the train a few
weeks ago, and noted that it is being encroached on by
suburbs. We had many a hot chase there over gorse and briar,
and always considered this butterfly the most difficult of all
to catch. I have never seen it in England since 1859 or i860.
Oxford, February II.

W. Warde Fowler.

Parrots in the Philippine Islands,

PraV allow me space to acknowledge a bad mistake which I
first made in the ninth editi. n of the " Encyclopsedia Bri-
lannica" (xviii. p. 322), and have lately repealed in the
"Dictionary of Birds" (p. 687), by asserting that | arrots are
■'wanting in the Philippine Islands." Seeing that the article
was written more than ten years ago, it is quite out of my
power to account for the mi-statement : my only wonder is that
it has not been before challenged, since there is, and has been
for some cent ures, abundance of evidence to show that there
are plenty of parrots in that group of islands, which, indeed, is
as well furnished with them (as remarked by my friend Mr. L.
W. Wigleswoith, who has kindly drawn my attention to my
error) as is the island of Celebes and I had already (p. 93)
noticed the Philippine spec es of Cockatoo.

Cambridge, February 9.

Alfred Newton.

TWENTY-FIVE YEARS OF GEOLOGICAL
PROGRESS IN BRITAIN.

T OOKING back across ihe fourth part of a century in
•'— ' the progress of any branch of science, we naturally
turn first to the list of names of those to whose labours
that progress has been due, anci though many of these
names may happily still be counted among the living, we
note many a blank where the hand of death has thinned
the ranks. Perhaps in this country no department of
natural knowledge can boast a more illustrious bead roll
than that of Geology. The story of the earth had hardly
begun to be scientifically studied until the first decades
of the present century, and some of the early fathers of
geology lived on until well within the life-time of the
present generation. A curious transition has thus been
going on during the last five-and-tvventy years. On the
one hand, there have been moving amongst us geological
magnates who achieved their fame in the old days when
it was still possible for a man to possess a tolerablv full
personal knowledge of almost every department of the
science. On the other hand, around these few living
memorials of the heroic age, grew up hosts of younger
men, who, finding the main lines already traced for
them, have become in large measure specialists, devoting
themselves with enthusiasm, but with more restricted
vision, to one formation, or one group of rocks, or one
tribe of fossils. The days of broad outlines and rapid
generalisation have gone. No new systems remain to be
added to the geological record of these islands. No new-
assemblages of e.xtinct types of life now reward the
sedulous collector. We have entered upon the era of
minute detail and patient elaboration. The field-glass
has given way to the microscope. The advance of the
science must now be based on laborious research, less
brilliant no doubt in its immediate effect, but probably
not less lasting in its influence and its results.

NO. 1320. VOL. 5 l]

368

NA TURE

[February 14, 1895

Among the gre.it leaders who have passed away within
the last twenty-tive years are some who have largely
helped to mould the whole fabric of geological science.
In the philosophy of geology, when will men cease to
venerate the names of Lvell and Darwin.' In laying
down the broad lines of stratigraphy, Sedgwick and
Murchison, Phillips, Griffith, Logan, Ramsay and Jukes
have left behind them imperishable monuments of their
genius. In the palxontological domain, among many
other illustrious men, Owen, Lonsdale, Salter, Davidson,
Morris, Wright and Egerton have left us. In other de-
partments of the science, our losses have been likewise
heavy — the gentle Scrope, pioneer of volcanic geology ;
Robert Chambers, who, after .Agassi/, led the way here in
the study of ancient glaciers : David Forbes, who did so
much to revive the study of rocks in llritain ; as well as
men like Page and .Ansted. who by their popular writings
helped to spread abroad an interest in geology.

Passing from the workers to the work accomplished,
we may note a few of the more prominent features
in the progress of geology in liritain during the last
(|uarter of a century. Space will not permit the
survey to be extended to the history of the science
on the continent of Europe and in North America.
.And first as to the general recognition of the science as
an important department of a liberal education. No
previous generation has seen so many proofs of this
recognition. Many new chairs of (ieology have been
founded in our universities and colleges. Te.\t-books,
class-books, hand-books, manuals and primers of the
science have been issued in edition after edition, and new
publications are constantly appearing. Field-clubs, and
other local associations, have started abundantly into
existence, and field-geology is one of their most attractive
features. .\t no time of its comparatively short history
has geology been more popular, in the best sense of the
word, than it is at the present time.

If one were asked to specify the feature which above
all others has marked the progress of geology in Britain
during the last five-and-twenty years, one would reply
with little hesitation — the enlarged attention given to the
study of rocks, or what is termed the petrographical
department of the science. For many years in this
countr)- that study was almost entirely neglected. The
attractions of fossils and of stratigraphy drove minerals
and rocks out of the field. .As David Forbes used sar-
castically to complain, geologists had forgotten that
their father was a mineralogist. They allowed the
petrography of the British Isles to lapse into a condition
of dire confusion, without system, without accurate
determinations, and without reference to what had been
done in the subject abroad. The lirst important step in
the way of reform was taken by one who is happily still
among us, Mr. H. ('. Sorby. Reviving the method of
making thin slices for microscopical examination, de-
vised by William Nicol, of Edinburgh, he applied it to
the study of rocks, and showed how fruitful it might be
made in investigating their history. Though his first
paper appeared in 1856, it was long in awakening
geologists in this country to the value of the new imple-
ment of research thus placed in their hands. It attracted
notice sooner in (iermany, and its applicability as
demonstrated there, led ultimately to its adoption in the
land of its birth. Hut only within the last twenty years
has it been acknowledged to be absolutely indispensable
in the investigation of the origin and history of rocks.

The introduction of the microscope as an adjunct in
research has entirely revolutionised the study of petro-
graphy. .\nd nowhere has the change been so marked
as in Britain. The former chaos has been in large
measure reduced to order. The rocks of this country,
instead of being neglected, are a foremost object of
study, and this branch of British geology has been
brojght abreast of the petrography of the continent.

NO. 1320, VOL. 51]

It is perhaps inevitable that in such a complete trans-
formation of methods, the new should be apt to be re-
garded as completely replacing the old way. The
microscope has done so much, that its potency may not
unnaturally be exaggerated, and a tendency so to
magnify it may sometimes be observed. But, after all,
the great field-relations of the rocks must in the first
place claim our attention and guide our reasoning. The
minute structures revealed by the microscope may be
made admirably serviceable in controlling that reason-
ing, and in supplementing the field-evidence by a new-
body of data otherwise unattainable. Vet the micro-
scope must remain the servant, not the master, in the
applications of petrography to the larger questions of geo-
logical theory.

If now w^ turn to the stratigraphical domain of
geology, perhaps the first remark that will occur to a
rertective observer is that a much closer attention than
ever before has been given in Britain to the investigation
of the most ancient accessible parts of the earth's crust.
The fundamental platform on which the oldest fossil-
iferous rocks repose, has been searched for with
enthusiasm, and though this enthusiasm has led to
mistakes, it has undoubtedly been successful in detect-
ing that platform in several places where it was not
before supposed to exist. The rocks of the platform
have been laboriously investigated, and have been found
to include both aqueous and igneous materials. Not
only so, but a succession has been observed among
them, vast sedimentary masses lying ununiformably on
still more ancient gneisses. In these sedimentary accu-
mulations no certain trace of organic forms has yet been
detected. Nevertheless the search has not been aban-
doned. If it should eventually be successful, it would
reveal evidence of a fauna or flora older than the oldest
relic of life yet discovered in liritain.

In the region where the most ancient gneisses are
typically developed, foliated representatives of almost
all the well-known plutonic rocks have been recognised,
and perhaps also, though dimly, traces of a group
of prima2val sediments, into which igneous masses
have made their way. We have thus been able to
take several distinct steps backward into the abyss
of time. We know more clearly than before the general
outlines of two or more great geological periods anterior
to the earliest relics of animal life. .\nd as a band of
zealous investigators is busy in the exploration of these
dim records, it is perhaps not too much to anticipate a
rich harvest of discovery from their labours.

Among the applications of paUcontology to the strati-
graphical side of geology, umiuestionably the most
important in recent times has been the recognition of
life-zones among the stratified formations, and the adop-
tion of these as a clue to the interpretation of the
sequence of strata, and even of tectonic structure. It
is long since the ammonite zones of the Lias, first worked
out in Germany, were traced in this country. Subse-
quently the pala-ontological platforms in the C halk, so
well developed in France, were found to hold good also
in England. Still more recently the vertical distribution
of graptolites has been shown by Prof. I.apworth to be
so restricted that these organisms may be used to mark
definite zones in the Silurian system. .\or is it in the
animal kingdom only that such restriction has been
asserted. The members of an extinct flora have been
found to show a more or less marked sequence of genera
and species, so that, alike in France and in England, the
Carboniferous system has been subdivided into more or
less distinct plant-zones.

The value of this pal.iontological aid in the investi-
gation of stratigraphical succession can hardly be over-
estimated. Among the undisturbed Secondary rocks of
England, indeed, it is not indispensable, for the sequence
of then formations and their subdi\i5ion> can be ac-

February 14, 1895]

NA TURE

369

larately determined there from other evidence. Neverthe-
less stratigraphical arrangement gains much in precision,
■\i well as in scientific interest, when changes in litho-
ogical characters are found to be accompanied by
;hanges in organic forms ; or, on the other hand, when
the succession of animal or vegetable types is found to
be repeated in distant localities irrespective of local
variations in lithology. But where the rocks have been
so folded and broken that from mere mineral characters
their true order cannot be made out, the presence in
them of determinable life zones, elsewhere well es-
tablished, may enable their complicated structure to be
unravelled. How this task can be successfully accom-
plished, has been well shown by Messrs. Lapworth,
Peach, and Home, in regard to the excessively convoluted
■structure of the Silurian uplands of the South of Scotland.

There is, however, some risk of error in the application
of this valuable aid in tectonic investigation, i Jbviously
:he existence of a life-zone, which will be of general
utility, must be determined upon a basis of evidence
.^ul^l'lciently wide to eliminate mere local peculiarities. It
should rest not on the presence of a single species, but
in a group of species or genera, for the narrower its
.lalivontological range the greater will be the risk of
elevating accidental into general characters. We cannot
suppose that a given species began and ended everywhere
at the same time or on the same platform. In some
areas the conditions would be favourable for its earlier
ippearance or longer continuance, so that we may expect
:he /ones not to be very sharply defined, but to blend
nto each other, and in such a way that if we were to
lefine them by single species we should find them to pre-
sent exceedingly variable limits. In a restricted region,
where the sequence of life-zones has been accurately
Ascertained, these platforms are of great value in work-
ing out questions of geological structure. But as we
recede from that region the necessity of caution increases.
The broad features of biological sequence will no doubt
remain, and we shall be able to say where the upper or
the lower members of a sedimentary series lie, but we
may be led into mistakes by trying too rigidly to make
the pateontological zones of one country agree with
those of another.

In the department of geotectonics, one of the most
interesting features has been the increased attention
bestowed upon the nature and results of the great move-
ments that have affected the crust of the earth. The
early experiments of Hall, showing that the stratified
rocks have undergone enormous lateral compression,
have been repeated and extended, and many of the
remarkable structures of mountain-ranges have been
successfully imitated. More detailed investigation has
been bestowed upon plicated and disrupted rocks, espe-
cially in Switzerland, Saxony and Scotland. The effects
of mechanical deformation in producing foliated struc-
tures, even in what were originally massive rocks, have
been copiously illustrated. The study of these questions
has led to a belter appreciation of the enormous plica-
tions, inversions, and dislocations which mountain-chains,
modern as well as ancient, have undergone. In the
.A.lps and in the Scottish Highlands, the subject has
been pursued with great ardour, and these regions will
henceforth be classical examples of some of the great
features of geotectonic geology.

Another distinguishing characteristic of the last
quarter of a century of geological progress has been the
increased interest taken in the history of the earth's
surface. It is strange that while, generation after
generation, men laboured zealously to investigate the
history of the planet as recorded in the rocks of the
terrestrial crust, they neglected to take account of the
superficial topography. They did not realise that every
land-surface is a kind of palimpsest, on which the chron-
icles of a long series of ages may be more or less dis-

NO. 1320, VOL. 51]

tinctly traced, and thus that every landscape has, as it
were, two histories : first, that of the rocks which form
its framework, and, secondly, that of the configuration
into which these rocks have been carved. It was in
Britain that this fascinating branch of geological inquiry
first took definite form in the early days of Hutton and
Playfair, and it is here that, after long neglect, it has
within the last twenty or thirty years been renewed and
pursued with most success. The varied geological struc-
ture of these islands, their changeable climate, their
mountainous groups, and long lines of sea-beaten coast,
make them exceptionally suitable for the prosecution of
this inquiry. But this branch of geology is now receiv-
ing even more attention in the United States than among
ourselves, and in many respects the geological structure
of North America offers peculiar advantages for its
cultivation.

It is impossible within the limits of this article to do
more than present in brief outline a retrospect of a few
of the departments of so wide a science as geology. Let
me, in conclusion, make reference to but one more subject
which has greatly exercised the minds of geologists
during the last quarter of a century. It is more than
thirty years since Lord Kelvin pointed out that there
must be an ascertainable limit to the antiquity of the
earth, and that from the data at that time available the
limit could not be fixed at less than twenty, or more
than 400, millions of years ago. He based this calcula-
tion on the thermal conductivity of the globe. After-
wards returning to the subject, he placed the limit within
100 millions of years ; and still more recently, reviewing
the question in the light of the arguments from tidal
retardation and the age of the sun's heat, he has brought
down the period of the earth's antiquity to about twenty
millions of years.

Geologists have not been slow to admit that they were
in error in assuming that they had an eternity of past
time for the evolution of the earth's history. They have
frankly acknowledged the validity of the physical argu-
ments which go to place more or less definite limits to
the antiquity of the earth. They were, on the whole,
disposed to acquiesce in the allowance of loa millions
of years granted to them by Lord Kelvin, for the trans-
action of the whole of the long cycles of geological
history. But the physicists have been insatiable and
inexorable. .As remorseless as Lear s daughters, they
have cut down their grant of years by successive slices,
until some of them have brought the number to some-
thing less than ten millions.

In vain have the geologists protested that there must
somewhere be a flaw in a line of argument which tends
to results so entirely at variance with the strong evidence
for a higher antiquity, furnished not only by the geological
record, but by the existing races of plants and animals.
They have insisted that this evidence is not mere theory
or imagination, but is drawn from a multitude of facts
which become hopelessly unintelligible unless sufficient
time is admitted for the evolution of geological history.
They have not been able to disprove the arguments of
the physicists, but they have contended that the physi-
cists have simply ignored the geological arguments as of
no account in the discussion.

So here the matter has rested for some years, neither
side giving way, and with no prospect of agreement.
Within the last few weeks, however, .is readers of
Nature will have observed, the question has been taken
up anew from the physical side.' Prof Perry, feeling that,
after all, the united testimony of geologists and biologists
was so decidedly against the latest reductions of time,
that it was desirable to reconsider the physical argu-
ments, has gone over them once more. He now finds that
on the assumption that the earth is not homogeneous,
as postulated by Lord Kelvin, but possesses a much
1 Nature, January 3 and February 7, iSgs; pp. 224-341.

370

NATURE

[February 14, 1895

higher conductivity and thermal capacity in its interior
than in its crust, its age may be enormously greater than
previous calculations have allowed.

The question bein^ su'' juiiice, we must wait until
it is settled. But there seems at present every prospect
that the physicists will concede not merely the loo
millions of years with which the ireolojjists would be
quite content, but a very much greater extent of time.

.\RCH. GeIKIE.

NOTES.

The second of the special meetings of the Royal Society is
nnoounced for the 28th inst., when Prof. Weldon will bring
forward as a subject for discussion, "Variation in .\nimal3 and
I'lanls."

A SUM of 12,000 francs (/480) was voted to the Mont Blanc
Observatory by the French Chamber on Tuesday.

Prok. Henry \. Rowland has recenily been elected a
Foreign .Member of the Reale Accadcmia dei Lincei cf Rome,
in the section of Physics.

The death is announced of the Marquis de Saporta, the
eminent botanist, at Aix. He was a Correspondent of the
Section of IJotany of the Paris Academy of Sciences.

.Mr. Reginald Stuart Poole, late Keeper of Coins at
ihe British Museum, died on Friday last, in his sixty-third
year. Few men have done so much as he to extend the study
of Egyptology and antiqiilies, or have added more to these
branches of knowledge. B:fore he was seventeen years o( a<»e
he wrote a series of articles on Egyptian chronology, which
afterwards appeared in book form under the title " IIorK
.E^yptiacae." He began very early to lecture on Egyptology
and numismatics, and in May 1864 made hii first appearance
in a Frid.iy evening lecture at the Royal Institution. In 1877
he became Keeper of Coin', and daring his twenty-two years'
tenure of that post he saw through the press thirty-five most
valuable catalogues of the collection; under his charge. He
was the author of the " Ciiies of Ejypt," and of the
articles on "Egypt," "Hieroglyphics," and "Numismatics,"
in the " Encyclop.xJia Brit^nnica." With Miss Amelia B.
Edwards, he was one of the founders of the Iv^ypt Explora-
tion Fund, of which he remained the honorary secretary to his
death.

A NEW scientific society, composed chiefly of the professors
and astistants in the P.iris Natural History Museum, has just
been founded. The .'ociely owes its existence to Prof. Milne-
Edwardt, the eminent diicctor of the museum. It is proposed
to hold monthly meetings, and to issue a Bulletin des
Naturaliilts, dealing with natural history matters.

The .Manchester Literary and Philosophical Society is for-
iunatcln having Mr. Henry Wildr. F.R.S., for hs president.
Alwayi one of the best of provincial societies, its usefulness
is likely to increase, for Mr. Wille ha'; intimated his intention
to endow the Sotiety with the sum of eight thou.sand pounds,
the annual income from which is to be devoted to various
porposd in connection with its work.

The hiilory of the Museum of the Corporation of London,
in the Guildhall, has never been written, although the collec-
lioni hoased therein are of very coniiderable interest and
value. Taking occasion of the visit of the Essex Field Club
on Saturday next, Mr. C. Welch, the Curator, will real a
paper on the "Origin and Progress of the Gjildhall Mujcum,"
to remedy this defect. The museum dcicrrei to b: better
NO. 1320, VOL. 51]

known and better housed than it is at present. A museum
fully illustrating the ancient history of London might easily
arise from the present collections, and would be a worthy object
for achievement for the richest Corporation in the world.

The Socieie Technique de I'lndustrie du Gaz en France
offers several prizes in connection with the Congress to be held
during the present year. The /.'urif^l of the Society of .\rts
says that the prizes open to all include one of 10,000 francs
(^400) offered to the inventor of an incandescent gas-burner
showing marked superiority, to be handed in to the Society
before .\pril i in the present year, unless the committee exer-
cise their power of extending the period for another year. The
sum of Sooo francs (^320) will be devoted to various prizes to
be awarded to the authors of the best papers on some subject
connected with the gas industry, such as the mechanical manti-
lenlion (h.indling) of coals, cokes, and the various substances
I used in gasworks, a study of watei-gas, and the substitution of
hydro-carbons forcannel coal. The papeis must be written in
French, and not bear the nime of the author ; but they must
contain at the commencement a motto, which must be repro-
duced on a sealed envelope containing a declaration, signed by
the author, that his work is unpublished, and that he will not
make any other publication on the same subject within a year.
The manuscripts, with sealed envelope, must be sent to the
Society, 65 Rue de Provence, Paris, at least forty days before
the period fixed for the Congress.

Dl'Rl.vr. the past week the severe frost has continued over
Ihe whole of these islands, and heavy falls of snow have
occurred in all throe countries. The distribution of pressure
has been generally anticyclonic, biting easterly winds, and gales
on our coasts. The following are a few of the lowest shade
minima published in the Pjily Weather Report of the Meteoro-
logical OflSce, since we last went to press : —

February 7

Nairn
Lough-
borough
London...

Cambridge

s

6

-5
to
6

-4
II

7

- I ...
13 ...

7 -■

I

20
•3

4
'5

2
IS

«s

In the neighbourhood of the metropolis some very low readings
were recorded on the Sih instant : Wallinglon 2''l, Croydon
5 '5, Tulse Hill 6°, Greenwich 69 ; and in other parts of the
country the following minima have been observed: —12° at
Braemar, - 8° at .Stamford on the Sih, 5 ' at Glenlee on the
gih, and a still lower reading, viz. -17°, is said to have been
observed at Braemar on the lith instant. The reading of 6" 9
at Greenwich is the lowest but one in ih; last 50 years, a tem-
perature of 6°'6 having been recorded on January 5, i860.
There had bee.i no reading there lower than 10 in February
during the same period, until the present frost, in which lower
temperatures have occurred on two successive nights. In
London such low tempeiatures rarely occur ; a minimum of
5° was obsirvoJ by Luke Howard on February 9, 1816.
.\nother feature of the present frost has been the low daily
maxima. On the i,)th instant it did not exceed 20° at Tulse
Hill. At (ireenwich the maximum temperature on January 5i
1894, was 19', which was then the lowest maximum observed
there since 1841.

Im a paper read before the ll.ilish Medical Association in
1889, Dr. .v. C. .Miller pointed ou'. that, under certain circum-
stances, advantage might be derived from high level residence
in the treatment of tuberculous conditions. A note, which has
a bearing upon this view, is contributed by him to the Jhitish
Meatdil fournal. The observers at the meteorological station
on the summit of Ben Nevis are cianged every three months
or so. While on duty at the observatory, they are, as a matter

February 14, 1J595]

NA TURE

n^

of course, exposed to the ri^jours and inclemencies of the
climate on the top of the m uTain, and are thas subject to I
conditions that, /W'/w/ar/V, mi^h' bi expected to favour the
>:carrence of catarrhs an 1 inflim nitions. Bit experience !
hows quite a different result. Tne observatory staff while in
actual residence on the summit has been remarkably free from
all kinds of ailments durin; the eleven years that have elapsed
since the opening. The subieqient residence at low level,
however, renders the members of the staff peculiarly liable to
an affection which clo;ely resembles, in most of its features,
what is usually recognised as an influenzal catarrh. There
seems Utile room for lioubt that this conlition is due to germ
influences in the lower atmosphere. .Vt the sum nit of the
mountain organisms do not exist, or if they do exis', only in
innocuous numbers. At the low level they relatively thrive,
and, seizing upon the " virgio S)il" of a renewed and sus-
ceptible mucous surface, they set up the phea omena described.

In the January and February numbers of the Geological
Magazine, Mr. E. P. Culverwell criticises severely the astro-
nomical theory of the Ice Age. He concludes that the change
in the distribution of the solar heat received by the earth
during a period of maximum eccentricity, would no', cause a
shifting of the isotherms as great as the displacements to which
the course of existing isotherms is subject from purely geo-
graphical cause;. If this is orrect, the cccentrici y theory of
the Ice Age must be abandoned. As a possible alternative
theory, Mr. Culverwell sugjests a variation in atmospheric
pres;ure through interchange of gases during the earth's passage
through space.

Some interesting additions to PaI:eobitany are being made
by Japanese geologists. In a recent paper {Journ. Coll. Sci.,
Imp. Univ., /afan, vo\. vii. part iii. 1894), Prof. Vokoyama
gives the results of his study of the fossil plants from several
localities on the outer or convex side of that remarkable island.
Unlike the plant-bearing beds of the inner, concave side,
which, so far as is known, are all Middle Jurassic, the strata
from which the floia in question comes appear to be comparable
in age to the Wealden of our o*n country. In the same
number, Mr. Nishiwada records the occurrence in Japan of a
Tertiary (probably Miocene) limestone with abundant remains
of the peculiar calcareous alga or "nuUipore," Litho-
tham nion.

Prof. A. Issel and Dr. G. Agamennone, who were deputed
by the Italian Government to investigate the Zante earthquakes
of 1893, have recently issued a viluable report of more than two
hundred quarto pages (Ann. Jeli Uff. Cent, di Met. c Geod.
vol. XV. part i. : Rome, 1894.). Dr. .\gamennone contributes a
catalogue of the earthquakes felt in Zinte from the earliest
times until 1893, and some general remarks on the same, as
well as chapters on the relation between the shocks of 1893
and the contemporaneous geodynamic phenomena in Italy, and
on the velocity of propagation of the principal shocks. Prof.
Issel describes the geology of the island, relates in ,'^ome detail
the features of the recent earthquakes, and concludes the work
with a chapter of theoretical considerations.

In a former note (p. 232), a brief description was given of a
remarkable group of earthquake-palsatioTS recorded at several
Italian obseivatories, and at Nicolaiew on Oc'ober 27, 1894. It
was supposed that these might have proceeded from the great
earthquake which occurred on the same day in Chili and the
.Vrgentine Republic. The doubt which formerly existed about
the time of the shock is now removed by the receipt of detailed
accounts. The first pulsations were registered at Rome at gh.
7m. 35s. p.m., , Greenwich mein lime, while the shock was
recorded at the observatory of Santiago (Chili) at 8h. 5000. 26s.,
NO. 1320, VOL. 5 l]

i.e. 17m. 9s. earlier. There can thas be little doubt as to the
origin of the pulsations, which probably travelled with a velocity
of nearly II k.m. per second.

A si.MPLiFiED process for silvering glass is described by MM.
.Vuguste and Louis Lumiere in the /jurnal de Physique. Take
100 parts by volume of a 10 per cent, solution of nitrate of
silver, and add, drop by drop, a quantity of ammonia, just suf-
ficient to dissolve the precipitate formed, avoiding any excess ol
ammonia. Make up the volume ol the solution to ten times the
amount by adding distilled water. The reducing solution used
is the formaldehyde of comaierce. Tne 40 per cent, solution is
diluted to a I per cent, solatioa. Tae glass to be silvered is
polished with chamois leather, and the bath is male up imme-
diately before use, by mixin^ two parts by volume of the silver
solution with one of formaldehyde. The solution must be
poured right over the surface without stopping. After about
five or ten minutes, at a temperature between 15° anl 19' C,
all the silver in the solution is deposited on the glass in a bright
layer, which is then washed in running water. It is then var-
nished if the ^lass side is to be used, or polished if the free
surface is required for reflection. This method does not require
the scrupulous care necessary wilh other methods, but Brashear's
process, for instance, gives mirrors which do not require
polishing.

The Government of Cape Colony has recently instituted
inquiries in various quarters with a view to gain sugjestions
as to the best methods of developing the neglectei sei-iisleries
of the colony. Tne Minister of Agriculture has received a
number of replies upon the subject, which have been published
in the Agricultural Journal of Cape Colony. The first de-
sideratum in a matter of this important nature is clearly that the
Government should possess some trustworthy and responsible
source of information upon matters connected with its sea-
fisheries ; and on this account Dr. Trimen, the Curator of the
South .Vfrican Museum, strongly recommends the Government
to obtain the services of a competent naturalist, accustomed to
the study of marine animals and, if possible, experienced in
the work of English or American Fishery Departments, who
would devote himself to a thorough study of South African
Fisheries. The appointment of skilled naturalists as Fishery
Advisers to Governments has been attended with excellent
results in Holland and other countries, and we heartily
endorse all that Dr. Trimen has to say in favour of the
adoption of a similar course in the present instance.

Messrs. Laws and Andrewes have not finished their
vindication of the innocuous nature of sewer air. We thought
that from the microbic point of view this question had been
disposed of ; but the London County Council evidently think
differently, and another report is to hand, telling us that the
microbes present in sewage are not present in sewer air, and
that there is no microbic relationship, either in quantity or
quality, between the two. These investigators claim to have
found a bacillus resembling the typhoid bacillus in a drain from
the typhoid block of a fever hospital in which no disinfection
had been carried out for two days previously. This is hardly
"an important fact," and perhaps not an unexpected dis-
covery; but it is interesting to note that when typhoid germs are
placed in sterile sewage, they are said to succumb rapidly,
whilst the closely allied B. coli communis multiplies extensively.
Details are given as to how the sewage was sterilised ; but
whether culture material was introduced along with the respec-
tive organisms, is not mentioned. We fail to understand why
the colon bacillus is described as "harmless"; it has been
shown to possess very distinct pathogenic properties. Experi-
ments were conducted to ascertain what effect certain sewage
microbes] would have on the vitality of the typhoid bacillus in

NA TURt

[February 14, 1895

sterile sewage, whether the demise of the Utter woald be
bastened or retarded by ihcir presence. In these investigations
•we are informed that the respective microbes were inoculated
into the sewage a'»r«/ /ri-m broth cultures, so that we cannot
accept the results obtained as representative. It has been
repeatedly shown what an effect the presence of even minute
traces of culture miterial has on the vitality of particular
microbes in water, &c., and wh.-it confusing and conflicting
results have been obtained by different observers working with
the same microbe through neglect of this simple precaution.
It is to be hoped that if any further experiments in this direc-
tion are contemplated, Messrs. Laws and Andrewes will bear
this fact in mind.

The inaugural lecture "On the Present Relations of Agri-
cnltunil Art and Science," delivered by Prof. R. Warington,
F.R.S., in the University Museum, Oxford, on the 4th insl.,
has been published by Mr. Henry Frowde. By a few state-
ments of fact, the Sibthorpian Professor shows that the agri-
cultural industry can only be placed upon a sound basis by the
full adoption of scientific methods and the recognition of
research. It is very well known that the provision for
agricultural investigations in England is at present wholly
inadequate. We have the important experiment station at
Rothamsted, and the Royal Agricultural's Society's station at
Wobum. Experiments are also carried on at some of our
agricultural colleges; but this represents practically all that is
being done here for the elucidation of agricultural problems.
Compare this with the provision made in other countries. " In
the German Empire alone there are fifty-four agricultural
experiment stations, besides numerous public laboratories for
the .-inalysis of manures, and seed testing. The experiment
stations are supported by aid from the State. The whole
number of experiment stations on the continent of Europe
is about 190. There are besides these, about 120 public
laboratories devcted to special kinds of agricultural work. In
the United .States, a great effort has recently been made to
provide the whole country with experiment stations. Every
State in the Union has now at leasl one station, supported,
since the year 1887, «ith an annual income of about jClooo
paid to it by the nation. The total number of experiment
stations in the United Stales is at present fifty-five . . . the
practical working out of agricultural problems can only be
accomplished by the establislmient among us of a considerable
number of experiment stations ; only in this way can science be
bronght into touch with practices, anil the teachings of science
reduced to that concrete form in which they can be put to pro-
fitable use by the farmer. Why should not our County Councils
found and maintain .in .ngricultural experiment station in each
county? Such a station would become a centre of light and
teaching to a large district."

Thb Proceeifiiii;! of the eleventh annual convention of the
Auociation of Official Agricultural Chemists, just distributed
bylheU..S. Department of Agriculture, enforces the remarks
Tcferrcd to above. The volume is literally full of facts iclaling
to agiictiltural chemistry. It contains many original articles,
abstracts of papett, analyses (iffeitiliscrK, foods, soils, and farm
products, and numerous reports. Unfortunately, the results of
such invest igal ions in the United Slates are not fully applicable
to British agriculture. What is wanted, as Prof. Warington
points out, is a central agricultural laboratory in England,
having as one of its duties the preparation of chemical
agricultural statistici. When thii has been established for a
few years, agriculturists will not have to confess ihnt they know
more about the composition and properties of German and
American produce than they 'I0 of similar products in our own
country.

NO. 1320, VOL. 5 l]

The tenth of the .\lembic Club Reprints, published by Mr.
W. F. Clay, Edinburgh, contains Graham's most valuable con-
tribution to pure chemistry, viz., the paper read before the
Royal Society in 1S33, entitled " Researcheson the Arseniates.
Phosphates, and Modifications of Phosphoric Acid."

All that is readable about comets is to be found in Mr.
Thynne Lynn's "Remarkable Comets" (Edward Stanford),
the third edition of which has just been published. Though
but a slender brochure of less than fifty pages, this little treatise
comprises most of the interesting facts in the history of cometary
discovery.

The new illustrated catalogue of electrical and other ap-
paratus, just published by Messrs Elliott Brothers, is capable
of giving the student of elementary science a liberal education
in scientific instruments. .Vlmost every important piece of
apparatus used in electricity is illustrated in the catalogue, as
well as the tools of research and education in other branches
of physical science.

The Calendar of the Department of Science and Art, for
189s, has been issued. For the benefit of those unfamiliar
with this publication, it may be worth mention that the
Calendar comprises a history and general description of the
whole Department, with a summary of the rules, and a list of
the Science and Art Schools and Classes, cintaining the
number of students in each school and in each subject.

In the Bullttin of the College of Agriculture of the Imperial
University of Japan (vol ii. N'o. 3), Prif. Sasaki gives a full
description of the scale insect of mulberry trees (Diasfis
fialelliformis, n. sp.) and of the principal features of its life-
history. A great deal of damage seems to be done by this
insect pest; and it would be well if tree-owners in Japan would
make use of the simple remedial measures reco'Timended by
Prof. Sasaki. The /}nllelin also includes a paper on the
spermatogenesis of the silkworm by K. Toyama.

In 1881, the first edition of " Elementary Lessons in Elec-
tricity and Magnetism" (.Macmillan), by Prof. S. P. Thompson,
F. R.S.,was published. Since then the book has been re-
printed, with alterations and additions, many times, and an
entirely new edition has now been issued. We are reminded
in the preface that during the fourteen years which have elapsed
since the book first appeared, electrical science and the science
of magnetism have been greatly advanced. Striking progress
has been made in theory and in practice, and the expansion of
knowledge has necessitated an expansion of the book. Whoso
seeks a class-book on electricity and magnetism, containing an
elementary exposition of recent work, will find their want
.supplied by Prof. Thompson's Lessons.

In Science JVo:;ress for February, Dr. C. S. Sherrington
F. R. S., describes the varieties of leucocytes. Mr. .\. C.
Seward concludes his second contribution on the structure and
formation of coal, with a paragraph which expresses his con-
viction that "the weight of evi<lence seems to lip the balance
of opinion very materially towards the theory of drifting and
subaqueous sedimentation, for the majority of the I'al.Tjnzoic
coal seams. " An account of the researches on the methods of
digestion in Ccclenterates, is given by Prof. S. J. Ilickson ;
Dr. W. F. Hume reviews works on geological folds and fault-
ing ; and Mr. Philip Lake adds to the literature of tectonic
geology, a paper on Neozoic — that is, Mesozoic and Cainotoic
— 6'°'°Ey '" Europe.

At present the English Arboricullural Society hardly justi-
fies its name, for it is more or less limited to the North of
England. There is every prospect, however, of its extension
southwards in the future, both on account of the attention now

February 14, 1895J

NA TURE

2>7:

being given to forestry, and because the Society is making
efforts to increase its membership by going further afield. The
Transaciions o( the Society, of which we have received a re-
cent issue (vol. iii part iv.), should materially assist towards
this end ; for the instructive papers contained therein appeal to
all foresters. In the Part received by us, there is an c^say on
" How Trees Grow," by Mr. J- Maughan ; an essay on
"Thinning Mixed Plantations," by Mr. \V. Forbes; and a
paper on " The Distribution of Trees in a Wood," by Prof. W.
Somerville. These are all useful contributions, but even more
important is the publication of the results of an inquiry, con-
ducted by the Society, into the disease of the Larch, a subject
about which much has been written and said. The information
•which Prof. Somerville has brought together, forms a valuable
summary if the present position of knowledge in regard to
the Larch disease, and shows the various conditions and
cultural methods which hold out some prospect of securing
comparative immunity from attack. With a larger membership,
the Society would be able to carry out, and publish, the results
of many similar investigations.

Pkof. Schiff and Dr. Tarugi describe, in a communication
to the Berichte, an admirable substitute for the disagreeable
sulphuretted hydrogen in qualitative analysis. The new re-
agent is the ammonium salt of thio-acetic acid, CH3 . COSNH^.
.\mmonium thio-acetale is decomposed by hot dilute hydro-
chloric acid, liberating sulphuretted hydrogen without any pre-
cipitation of sulphur. No objectionable bye-products are
formed in the reaction, only sal-amminiac and acetic acid being
produced. When a feebly ammoniacal solution of ammonium
thio-acetate is added to a hydrochloric acid solution of the
metals of the second group, and the liquid is heated to near
boiling, the metals are at once precipitated as sulphides, while
only the faintest odour of sulphuretted hydrogen is perceptible.
After cooling and filtering, the filtrate is found lo contain no
trace of the metals, not even of arsenic if an arseniate had
been originally present. The completeness and rapidity of the
reaction, particularly in the case of arsenic, which is usually sd
troublesome to precipitate fr om arseniates, is one of its strongest
recommendations, and is described by Prof. SchifT as being
perfectly surprising. A couple of cubic centimetres of a 30
per cent, solution of ammonium thio-acetate is usually ample
for a gram of the substance to be analysed. The reagent has
been employed for sometime by Prof Schiff in the Pisa labora-
tory, and is much appreciated by his students, sulphuretted
hydrogen being completely excluded fro'U the laboratory,
doubtless to the material advantage of all concerned, both as
regards comfort and health. Thio-acetic acid is readily pre-
pared by acting upon glacial acetic acid with phosphorus
pentasulphide. It boils at 95', and is but slightly soluble in
water. When the acid is dissolved in a slight excess of dilute
ammonia, a yellow solution is obtained, which is then diluted
to three times the volume of the acid originally taken -that is,
10 cubic centimetres of the acid furnish 30 cubic centimetres
of the reagent. Prof. Schiff serves the reagent out to his
students in small bottles close I by a cork, through which a
small pipette, holding 2 cubic centimetres, is inserted, by means
of which the convenient quantity of the reagent can at once be
added to the hydrochloric solution of their test substance. It
is scarcely necessary to add that zinc, manganese, nickel, and
cobalt are not precipitated in the presence of hydrochloric acid
by the new reagent, any more than by sulphuretted hydrogen
itself. The sulphides of these metals are al once precipitate 1,
however, upon rendering the solution alkaline ; but as
ammonium sulphide acts quite as well for this purpose. Prof.
Schiff confines the use o( ammonium thio-acetate to the pre-
cipitation of the metals of the second group.

NO. 1320, vor, 51]

The additions to the Zoological Society's Gardens during the
past week include a Lion {[■'di^ Lo, i ) from India, presented
by H.R. H. the Duke of C^onnaught ; a Cape Bucephalus (Buce-
phalus capensis) from South Africa, presented by Mr. J. E.
Matcham.

OUR ASTRONOMICAL COLUMN.

The Mass OF THE Asteroids. — A preliminary note on the
probable mass of the asteroids was contributed by Mr. B. M.
Roszel to the yohns Hopkins Universily Circular in May 1894,
and summarised in these columns (N.\TURE, vol. 1. p. 87.) In
that paper Mr. Roszel limited himself to determining the mass
from a study of 216 minor planets ; he has now extended the
computations to 311 asteroids, the orbits of which are given
in the Berliner Astronoiiiiiches Jahrbuch for 1894 {University
Circular, January 1895). His chief object was to find a probable
limiting value for the mass,rather than an accurate determina-
tion of the mass itself. Using the photometric determinations
of the diameter of Vesta, by Pickering and Miiller, and the
direct measures of the diameters of Ceres, Pallas, and Vesta by
Barnard, Mr.Roszel has reduced the volumes of all theasteroids
to the volume of Vesta, except when Barnard's measures were
the basis, in which case he computed the volumes of Ceres and
Pallas separately, and added them to the combined volume of
the remaining 309. Assuming the albedo constant and a con-
stant density equal to the density of Mars, he obtained the
following numbers :

Combined volume of 311 asteroids . 5185 vol. of Vesta.
,, ,, omitting Ceres and

Pallas. . . 2684 ,, ,,

Volume of Vesta, in terms of volume of Mars :

(1) From Pickering's estimate of the diameter

of Vesta, assuming the albedo = albedo

of Mars . . ' --- 000022

(2) From Mailer's estimate, assuming {«) the

albedo = albedo of Mars . . . = 000065

(3) From Mliller's estimate, assuming (b) the

albedo = albedo of Mercury . . . = 000129

(4) From Barnard's estimate of the diameter of

Vesta = 000018

Combined mass of 3 1 1 asteroids, in terms of mass
of Mars :

From Pickering's estimate, as above . = 0001 12

,, Mliller's estimate, as above (a) . . = 0-00336

,, ,, ,, ,, (/') . . = O'oo666

,, Barnard's measures . . . . — 000273

The mean diameter of Mar^ was taken as 4230 miles. It
appears from the above numbers that the combined mass of
the asteriods is about '026 of the muss of the moon.

The Apparent Diameters ok Mercury. — During the
transits of Mercury on May 9, 1891, and November 10, 1894,
Prof. Barnard gave special attention to measurements of the
planet's apparent diameter. {Ast y cwr. No. 335.) In both cases
the diameter in R. A. was found to be slightly greater than that
in declination, and if this be not a mere accidental coincidence,
as Prof. Barnard seems rather inclined to believe, it would
indicate a small polar compression. The measures at the two
transits respectively indicate a polar compression of 1/134 and
1/98, or a mean of 1/116. Though by no means insisting on
the reality of the difference in the diameters. Prof. Barnard
points out that " the results may be of great importance in the
future, as hearing upon the rotation of the planet on its axis in
a reasonably short period." Expressed in angular measure,
reduced to unit di>tance, the two diameters as measured in
1894 were 6''24I for the "equatorial," and 6 '178 for the
" p )lar " diameter. It is incidentally mentioned that " though
Mercury cannot be seen at transits with lire naked eye alone, it
only requires apowerof 2\ diameters to make it easily visible. "

The Variation of Latitude.— The results obtained by
Mr. Chandler in his investigations of variation of Latitude seem
to be confirmed by M. Ivanof's recent discussion of the older
series of observations made with the great vertical circle at
Pulkowa. (.Ji/. y^M?-. No. 335). " There is no doubt that two
periods subsist ; one equal to 428 days, the other to a year.
Also, the semi-amplitudes of both terms are variable beyond
any doubt."

574

NATURE

[February 14, 1895

w

THE SUN'S PLACE IN NATURE.'

THEN', in |SS6, it became my duty to give a course of
lectures here, 1 thuujhl it advisable to deal with the sun
and stars, not w.th lefercnce specially to solar ph)sics, but in
order to give a geneial idea of two impjrtant lines of work
which were running! hen nearly piiallel to each other, and pro-
mUed soon to meet, w.ih ihe tjieaiest benefit to science. Only
a very little was said in those lectures touching the relation of
stars to nebuli, and the variou- views which have been held
time out of mind with regard to the special nature of both these
classes of celestial bodies. Sach questions, however, have
always had the greatest interest lor mankind, for th >se at all
events among us who Iikc'o know someihini;atiout the universe
in which our lot is cast. No .livi.lends, unfortunately or fortun-
ately, depend upon the discussion or even the application of
any branches ol Inquiry which are necessary in order to make
progress along the lines of thought thus opened up; scant
attention is paid to them by educational bodies, for they lead
to no profession ; hut in siiiie of that, some of the noblest
triumphs of the human m.nd have been made in that legion
where man finds him.elf face to face with the mysteries of the
distant heavens. . . ■ . ■

To consider completely the Sun s Place in Nature, which is
the subject I have chostn for this present course of lec-
tures, the relation of these two apparently different classes of
celestial bodies to whi^h I have referred, must be gone into.
Thanks to the advance of modern science, I shall be able by-
and-by to throw upon the screen pictures of clusters of stars,
and of nebulae, in which you will see those bodies very much
better than you could do if to-night you were in one of
the best equipped observatories in the world, for it so happens
that the enormous progress which has recently been made in
the application of photography to astronomical work enables us
to get permanent records of parts of them which are so dim that
they never have been and never will be direcily revealed to the
eye of mortals. ■ , . j-

When we compare these two great groups of celestial bodies
we find that, at all events in appearance, there is an enormous
difference between them ; that a nebula is certainly unlike a
star, or even an ordinary star cluster. This is so obvious that
even those who first observed those very few nei)ula; which are |
visible to the naked eye (such a one, for instance, as that which
is now beautifully visible to us in the early night in the nebula
of Orion, or the other in Andromeda, which we can see almost
throughout the year), the greatest wonderment was caused by
their strange appearance.

Let us go back 150 years. I have here a book ("Les
Hypotheses Cosmogoniques"), recently written by a distin-
guished French astronomer, M. Wolf, which contains a
reference to what the French philosopher .Maupertuis said
about them in the year 1 745. ' ' The first phenomenon is that of
those brilliant patches in the sky which are named nebul.ne, and
have been considered as masses or groups of small stars ; but
our a-tionomers, with the aid of better telescopes, have only seen
them a« great oval areas, luminous and with a light brighter
than the rest of the heavens. Huygens first discovered one in
the constellation of Orion ; llallcy, in the Philosophical Irain-
adioiis, pointed out six, the first in the Sword of Or^on, the
second in the con-.tellation of Sagittarius, thethird in the Centaur,
the fourth before the right foot of .\ntinous, the fifth in lUrcuIci,
and the sixth in An Iromeda. Five of these spots having been
obs'ived with a reflector of 8 ft., only one of them, the fourth,
could le taken for a group of stars ; the others seem to be great
shilling areas, and do not differ among themselves, except that
tome are more round and others more oval in shape. It seems
aUo that in the first the little stars which one discovers with the
telescope are not capable of causing this brightness, llallcy was
much struck with these phenomena, which he believes capable
of explaining a thing which seemed difficult to understand in
the H)ok of (ienesis, viz. that light was created before the sun.
Durham regards them as holes through which one discovers an
immense region o( light, and finally the empyrean heaven itself.
He professes to have been able to distinguish that the stars
which are seen in tome of them arc very much less distant fiom
ui than the tpoti of light themielvej."''

' R!»i»ed from »Horthinil n««« of a courie of leciures lo working mm
al llii MuKUin of IVaclical Gto'ogir daring NovcmUcr and Dectmttr,

' '■ O.icoi" •iir le« diff''renKi fuurtt de« A«lr««," chap. vi. pp. 104-14.

NC. 1320, VOL. 51]

I need no: follow the quotation any further, but you see
that 150 years ago some of our keenest intellects we-e struj
gliDg with the questions involved in mystery which had been
started by the discovery of these nebulous bodies in space. That
was in the year 1745. Soon after this, in the year 1755, Kant,
who was a German, though he was by direct descent a
Scotchman, brought out an hypotlie-,is in which he attempted
to show thit there was the closest possible connection between
stars and the clusters and nebula; of which Maupertuis spoke,
lie held distinctly that the stars were produced by some action
brought about in nebulae ; in other words, that the nebula:
represented a first stage out of which stars, representing a later
stage, were produced by certain proce^ses of evolution.

From 1755 we pass to 1796, at which date we find a great
Frenchman (Laplace) pr.actically lediscovering and reasserting
the same thing. It is believed that he knew nothing of Kant's
prior work, and therefore we have the advantage of dealing
wi h the results of the thoughts of two great minds. Laplace
came to the same conclusion as Kant, so far as it »ent, but he
went further than Kant did, beciuse he held that the nebul*
really represent enormous masses of clastic gas at high tem-
perature, and that therefore the stars, which he conceived, as
Kant had conceived, to be produced l>y evolutionary processes
from these nebulae, were really produced from incandescent
masses of gas.

Now, seeing that our sun ii a star, it is perfectly clear from
this that both Kant and Laplace agreed that the sun, represent-
ing a star, had originally been produced from a nebula. Thai
is my first point.

About the time of Laplace, i.e. about 1796, Sir William
Herschel was making England famous by the discoveries
rendered possible by that w.ndeiful telescope which he had
erected at Slough. There, for the first time, the possible sim-
ilarities and the possible differences of these two great groups
of celestial bodies were subjected to the most minute and lab-
orious scrutiny. Well, he came a'.solutely to ihe sa'iic conclu-
sion as his predecessors had done, and (or Sir William Herschel
there was no doubt whatever that from the most irregular
nebula ti the densest star theie was a gradual process of
change ; that there was no radical difference, but that the star
represented simply the result of certain evolutionary changes.
This view thus strengthened held the field for some years ; then
a larger telescope was made by Lord Rosse, a 6fool mirror was
now available instead of the 4foot one which had been erected
by Herschel at Slough. Lord Rosse— you will fiml the
whole story admirably told in Prpl. Nichols book, " Ihe
Architecture of the Heavens "—came to the conclusion that
when he observed a so called nebula on the finest possible
nights, when the air was stillest, and the magnifying power which
he could use was greater than usual, he could see what he called
the possibility of a resolvabiliiy in it. That is to say, nebulx
might after all really be star clusters, only immensely
rem.te, so that Ihe light of all the stars was, as it we"- «»
welded together as to give that appearance of a candle
seen through horn, which Maupertuis and his predecessors
had observed.

Next wecome to the year 1862, and we find a new instrument
brought to bear, which at once drove into thin air all the state-
ments which had been made on what had turned out to be a
line of inquiry which was incapable of giving a final verdict.
It so happened that in that year there was a very powerful
combination formed by a distinguished chemist and philo-
sopher. Dr. William Allen Miller, the Treasurer of the Royal
Society, who had already done most admirable spectroscopic
work, and a neighbour of his, Mr. Iluggins, who had
mounted a powerful telescope in 1856. The spectroscope,
which was then practically a new instrument, was applied lo
the telescope. ,

I need not say much about the spectroscope, as I have alnady
had an opportunity of describing it to some of you, but I may
in a few words show exactly the function of this new instru
ment of enormous power, which has in a very few years perfectly
changed the aspect of astronomic science. If we pass a ray il
while light through a piece of glass called a prism, we find ihit
alter the light has so passed through, it is chinged i.nto a beau-
tiful bind, showing all the colours of the rainbow. I his prism
then is the fundamental part of the instrument which is calleil
the spectroscope, and Ihe most complicated spectroscope which
wc cin imagine simply utilises the part which this piece ol
1 triangular glass plays in breaking a beam of light of any colour

February i4> 1895]

NA TURE

575

irrto its constituent parts Trom ihe red to the violet; between
these colours we get that slrinij of orange yellow, green, and
blue which you are familiar wiili in the lainbow. For six|)ence
any of you may mike for your^rlves an instrument which will
serve many of the purpo-^es of demonstrating some of the more
beautiful fields of knowledge which have been opened up

Fii.. I, — A simple form of spectroscope.

t" as by its use. From an optician you can get a tiny
prism for sixpence; glue it at one end of a piece of
wood about 12 x i x A inch, so that you can see through
it a coloured image of a needle stuck in at the other end of the
piece of wood (Fig. i). This you must dj by looking sideways
tliroughit. Allowyour needle to be illuminated by a candle or a gas

Fig. 2. — Star spectroscope, arrangcii for photograpliinij. attached to eye-end of reflecting telescope.

Ihme, taking care that the direct light from the car.dle does
not fall upon the face of the prism ; you will then get a com-
plete band of colour from red to blue. If you go into the sun-
light— taking care again to protect the prism itself from the
entrance of any foreign light — and allow the sunbeam to
illuminate your needle, you get a spectrum of a different kind,
full of black lines.

NO. 1320. VOL. 51]

By such experiments as that, certain spectroscopic axioms
have been formulated : three of them are very impoitani.

First, when solid or liquid or densely gaseous bodies are in-
candescent, they give out continuous spectra.

Second, when a solid or lujuid body reduced to a slate of gas,
or any gas itself, is giving light, the spectrum consists of bright
lines, and these lines are different for different substances.

Third, when light from a solid or liquid body passes through
i;as at a lower temperature, the gas absorbs those particular rays
( f light r f which its own spectrum consists.

We will next suppose, then, a spectroscope placed at the eye-
end cf a telescope (Fig. 2). The question put to the combined
instruments is : What is starlight like ? It was found that the
stars give a spectrum very much like the spectrum of the sun, in
most cases at all events, and that this spectrum could be defined
in the light cf the third axiom, that certain of the light was ab-
sorbed, there were dark lines in the spectrum (Fig. 3); and thus we
knew that light had been absorbed by an atmosphere surround-
ing something which was very much hotter than itself, and in
that way the science of solar and stellar physics was founded.

Suppose another question put to this instrument: What is
the light of the nebula; like?

I have already told you that Laplace held that in these bodies
we were dealing with gas at a high temperature. From the
time of Tycho Brahe down«ards, people had an idea that the
nef.uJK were "fiery." What should we expect to get in our
instiument? The second axiom tells us that, if we are dealing
vvith matter in a state of gas, or anything vapourous at very high
temperature, we shall get bright lines only. The question as to
the nebulae was put in 1864, and, curiously enough, when the
observation was made. Dr. Muggins remarked: "I suspected
some derangement of the instrument had taken place, for no
spectrum was seen, but only a line." "Only a line" was exactly
what I suppose Laplace would have given all he possessed to see,
if spectrum analysis had been invented in his day. That line
settled the question. There was certainly a tremendous spectro-
scopic difference between stars and nebulae, and this difference
has been emphasised by subsequent researches. (See
Fig. 3.) It is evident, therefore, that Lord Kosse's sus-
picion that the rebula; might, alter all, be found to be resolvable
into star clusters when greater op-
tical power was used, was proved
to be erroneous.

Now we come to the second
point. I indicated in the previous
course of lectures that th re were
differences among the stars, de-
pending possibly upon chemical
constitution, or temperature, or
even upon their ages, and that the
stars had been classified by several
very diligent inquirers. Also, that
in all the classifications that had
been attempted, it was universally
taken for granted, for some reason
or other — possibly in view of the
idea of Laplace — ihat all the stars
in the heavens began in the con-
dition of highest temperature, and
that all that the stars did after that
was to spend their millions and
billions of years of life in getting
colder; so that, if we could at the
present moment find out which was
the very hottest star in the heavens,
wc might be perfectly certain that
every star in its beginning re-
sembled exactly in spectrum, and
therefore in physical constitution,
that particular star which we sup-
pose to be the hottest. It so
happened that in that very course
of lectures I pointed out, for the
first time, I think, in reference to the separation of stars
into classes, that such an idea as that would never do;
for if we form any conception of nebula; changing into stars,
we begin by knowing that the slats are veiy much denser than
the nebula;— taking the sun as an instance, the star practically
close to us— and that as the stars are denser than the nebulB,
they must be hotter than the nebulae, instead ol being colder.

376

NA TURE

[February i4i 1895

This depeoded absolutely upon the application of ihermo-
dynaraics. and had been pointed out by Helmholtz in the year
1845. Sir William Thomson, now Lord Kelvin, also pointed
out quite distinctly that the liypothesis of fiery nebulous matter
— ^by that meaning nebulous matter hotter ilun the s'ars —
was invented before the discovery of thermodynamics ; other-
wise, he said, the nebulx would certainly never luve been
conceived to have been fiery, i.e. something hotter than the
average sur.

I then went on to show that Lord Kelvin told us how he
-onld imagine a condition of nebula- which might ultimately
condense into stars without violating the laws of thermo-
dynamics, which were ompletely traversed by Laplace's view ;
and he referred In a sugjestion that hid been made by Prof.
Tait, who supposed that the luminosity of nebula-, and even the
spectroscopic appearances which have been observed, might be
explained bysuppo^ing that weweredealing with gaseous exhala-
tions proceeding from the collisions of meteoric stones ; and he
also pointed out that possibly that would not only explain the
luminosity of nebula-, but ilie luminosity of comets a-^ well. By
the kindness of the Director of this Museum, 1 have some
-•specimens of these meteoric stones on the table. I would re-

might be explained by the fact thai, in consequence of the
collisions between these bodies occurring under different con-
diiion.s and at ditTerent velocities, there would be very consider-
able difterences in ihe temperatures produced in the two cases.
Similar conditions might hold (orsiarsindifferent degrees of con-
densation. It was also suggested that this new idea might explain
the phenomena of variable and new stars, which have always been
accounted to be the most extraordinary and mysterious in the
whole domain of astronomy ; and, finally, I said the subject was
well worthy of study, because it seemed as if many phenomena on
the nearest star to us, our own sun, might be really phenomena
produced by the fall of meteoric bodies upon that surface which
we see, and which we call the photosphere. It is now many
years ago since Balfour Stewart and others threw out the idea
that the phenomena connected with the formation of sun-spots
were really produced by the fall of bodies upon that surface.
Other philosophers have preferred the idea that we have to
do with eruptions from the interior of the sun ; nothing can be
more divergent than the opinions which have been broughi
forward as explanations of these appearances.

But you at once see that, if we assume that (his meteortic
action may take place in the solar atmosphere, it need not

a HERCULIS u-Roup ij)

■;< CVJ\. ;o;.

_L

.\*<v

Fig. 3. — The photographed jipeclnim of.-! nebula, conli. -uteri with the speclr.-» of stars.

mind you that the few specimens which I have here have been
selected from Ihe magnificent collection upstairs ; if you have a
few minutes to spare after this lecture, you cannot do better
than go and have a look at them, and you will sec how very
various both to the eye and in chemical and physical consfiiulion
they are. I.ct me also recommend you to get a little pamphlet
(price 2</.) containing a description of the me'eori-e collection
in Ihe Natural History Museum, which is one of the finest in
the world.

We thus arrived .-11 the idea that these wonderful ncbul.a- may
be explained, apart from any fiery gas ; that we have simply to
look lo a meleorilic origin to explain both Ihe appearances and
the spectrum.

After that point had been made, I went on to make another.
I had already referred 10 the claMificalion of stars, and I
remarked that if one looked at Ihedifferent groups of spectra, it
neemed an if a cla»«ificaiion of Ihem, l>a»ed nn thc«e idea», did
fit Ihe fact! heller, the existing ones depending on Ihe iinphilo-
sophic one of I^aplace. It i< possible, I said, ihat Ihe great
tlifference" which had been observed in iheKpccira of comelsand
of nebulae, allhough the origin of Ihe light of both was ascribed
olhecla-hing together of Lionel in ctifTerent pans of space,

MO. I.-^ZO vol.. - 1]

necessarily be a meleorilic action coming from without. Taking
our own case, we live in a damp climate, and sometimes the air is
dampest when there are no clouds. Clouds are condensations
of ilie moisture in the air, and we know that it is not really
a question of clouds only ; we may have snow, rain, or hail, and
.ill these represent diJTerenl condensations of the damp — or, as
we call it, the aqueous — vapour which is ever present in ourair.
.-\pply lhat In the sun. What is the air of the sun composed of?
Well, ceriainly one important constituent of it is the incan-
descent vapour of iron ; we are no longer dealing with a low
lemper.aluie and the vapour of water, hut with an atmosphere in
the hotter parts of which iron is nn' solid or liquid, but in
which the temperature is high enough to keep it in a slate of
gas, probably thousands of degrees higher than is arrived at in
the Bessemer process.

We villi assume, then, lhat lhat temperature and that con-
dition of atmosphere prevails for 20.000 (it is protubly nearer
50,000) miles above the photosphere of the sun. As we get
Itirlhcr from the sun, the atmosphere is of course gel'ing cooler,
and at a certain distance almve the photosphere Ifie temperature
will be so reduced thai the iron vapour iniijlit ))lay the part of
our aqueous vapour ; then it condenses and turns into iron snow

February 14, 1895]

NA TURE

377

and iron hail and iron rain, and so on, falling upon the photo-
sphere as the rain falls on the earth. There is thus a possi-
bility in the sun of home made meteoritic action.

So far as my last course of lectures was concerned, I there
ended that part of the subject. IJut so many points bad been
raised in trying to give a connected view of these two very
slowly converging lines of research to which I referred, that, after
the lectures were over, I determined to discuss the various
points which had been raised. I determined to take up
Prof. Tait's suggestion, and see how all the spectrosc 'pic obser-
vations which had been made up to the time of my lectures in
1886, bore out that suggestion which had been made in 1S71,
before there was very much spectroscopic evidence to go upon.
The result was that my assistants and myself spent something
like three years in gathering together, we believe, every avail-
able observation ; at all evenis, if not every available observa-
tion, there were between thirty and forty thousand of them, and
we found that a very considerable number. I not only deter-
mined to collect them, but also to discuss them, and make any
experiments or observations which might be suggested by the
discussion. The result of this was that, as a fruit of that course
of lectures, several papers, some of them very long — it is not
for me to say anything as to their value — were sent in to the
Royal Society, and eventually brought together in a book.

Now, what I found was that when we discussed the
meteoritic view in the light of all the ol)servations we could get
together, and in relation to stars as well as nebula: and comets,
it seemed to explain many things, and threw a perfectly new
light upon the visible universe ; there were, moreover, several
points raised of intense novelty and freshness, each of which
could be discussed separately, cast aside if it were false, and
held on to if it were true. I give a table of some of these new
points of view.

New points of view in the Meteoritic Hypotiiesii.

(1) There is the closest possible connection between nebuhe
and stars.

(2) The first sta'Te in the development of cosmical bodies is
not a mass of hot gas, but a swarm of cold meteorites.

(3) Many bodies in space which look like stars are really
centres of nebulae ; that is, of meteoritic swarms.

(4) Siars with bright-line spectra must be associated with
nebula;.

(5) Some of the heavenly bodies are increasing their tem-
peratures ; others are decreasing their temperatures.

6) Double swarms, in any stages of condensation, may give
rise to the phenomena of variability.

(7) New stars are produced by the clash of meteor swarms.
They are closely related to nebul.L and bright-line stars.

(8) Cosmical space is a meteoritic plenum.

(9) A new classiiication of the heavenly bodies, based on the
varying states of condensation of the meteoritic swarms.

(10) The sun is one of those stars the temperature of which
is rapidly decreasing.

(11) Many of the changing phenomena of the sun are due to
the fall of meteoritic matter upon the photosphere.

We ultimately arrived at the conclusion that the .sun is one of
the stars, the temperature of which is gradually decreasing,
and that many of the phenomena of the sun are due to the fall
of meteoritic matter on the photosphere.

The doing of a large piece of work like that — and I .say it is
large because I am glad to have the opportunity here of ex-
pressing my gratitude to my asistants, who stood by me for
three years — brings one out pretty well into the open, and
renders one liable to a brisk fire of criticisms, some very valuable,
some quite unworthy of the critics.

You will see that the work was undertaken with a view of
determining the sun's place among the stars.

J. Noi;man Lock\ liK.
(To be continued.)

THE INSTITUTION OF MECHANICAL
ENGINEERS.
'T'HF. annual general meeting of the Institution of Mechanical
•*■ Engineers was held on Thursday and Friday evenings,
the 31st ult. and the 1st inst. Prof. A. B. W. Kennedy, !•". R. S.,
occupied the chair. There were two papers set down forreading
and discussion :

*• The Determination of the Dryness of Steam." I'.y Prof.
W. Cawthorne Unwin, I'. U.S.

I

"Comp.irison between Governing by Throttling and by
Variable Expansion." By Captain H. Kiall Sankey.

Prof. Unwin, in his interesting paper, gave descriptions of the
best known methods oldetermining the mean of moisture in steam
up to now introduced. Most of the apparatus described was
exhibited on the talile of the theatre, whilst diagrams illustra-
tive of them were hung on the wall. The author pointed out
that the earliest attempts to determine the amount of moisture
in steam, of which records have been found, were made during
some boiler trials carried out by a committee of the Societe
Industiielle of Mulhouse in 1859. This committee tried three
difierent methods — a method of separation, a condensing
method suggested by Hirn, and a chemical method. In these
early trials the condensing method only, in which the total
heat of a sample of the steam was measured, appeared to give
saii-facloiy result ~. But although the committee did not place
full reliance on any of their methods, these have all been used
by various experimenters down to the present time.

The origin of water entiained in steam. Prof. Unwin said,
was to be attributed to three causes :

(i) Water projected into the boiler's steam space during ebul-
lition. The extent to which wetness occurs depends on the
activity of the ebullition, the area of the water surface, the
volume of the steam space, the position of the steam valve, the
density of the steam, and. probably more than anything else,
on the quality of the water and its liability to produce foam.
The author referred to the experiments of Mr. Thorny-
croft, who constructed a boiler with glass ends, through
which the process of boiling could be sten. The result of
oljservations on this boiler showed ' that waters which cause
primmt; produce foam on boiling. Water which is very bad
produces bubbles so durable as to remain a considerable time
without breaking ; and by them the steam space of a boiler may
be entirely filled. So soon as this takes place, instead of simply
.steam leaving the boiler, the ilischarge consists of foam, which
becomes broken up in its rapid passage through the steam-pipe.
With pure water, steam retains no film of liquid long enough to
be seen.

(2) Water may be produced in steam from the expansions to
which it is subjected. Fluctuations of pressure arise from the
intermittent demand for steam, and from the steam passing from
places of higher to places of lower pressure. Prof. Unwin con-
sidered it difficult to believe that any great amount of wetness
arises in this way in ordinary cases.

(3) The steam in the boiler, and the steam-pipes, loses heat
by radiation. Probably in some cases considerable wetness is
produced in this way. The wetness of the steam, so far as it is
due to this cause, will increase a; the demand for steam
diminishes.

The author next went on to deal with the various methods of
determining the wetness of steam, referring first to the weighing
method, by which a known volume is weighed, when any excess
of weight above that of a corresponding volume of dry saturated
steam must be due to the water present. This method is
obviously one of excessive difficulty.

The sujierheating method was next referred to in the paper,
the experiments of Barrus and Carpenter being quoted. The
Carpenter calorimeter consists of a vessel about 12 inches
high by 5 inches diameter, consisting of an inner chamber and
a jacket. The steam from the steam-pipe passes first to the
inner chamber, where the moisture is separated, .and then into
the outer chamber. The separating chamber is therefore per-
fectly protected from radiation. .Vs the water accumulates in
the inner chamber, its level is shown by a gauge glass, .and the
amount in hundredths of a pound can be read otT on a scale.
A very small orifice at the bottom of the outer chamber regulates
the amount of sleam discharged. The escaping steam passes
through a llexihle tube to a simple form o( condenser. The
increase of weight in any given time in the condenser is noted,
and the amount accumulated in the same time in the separator.

The condensing method was next described. This is founded
on the condensation of a known weight of steam and the deter-
mination of its total heat by the rise of temperature in the
condensing water. By comparing the total heat per pound of
a sample of sttam with that of a pound of dry saturated steam
according to Regnault's tables, the amount of moisture in the
steam can be determined. This method was first suggested by
Hirn, and the apparatus which he designed is perhaps the most

> " Circulation in the Thornycroft Water-Tule Boiler." Tianmiihtis of
the Inslitulton of Nav.-il Archirects, :S94.

NO. «.320, VOE

51]

37S

NATURE

[February 14, 1895

convenient foini of apparatus for determinations by this method.
It consists of an iron vessel about a foot in fiiame'er, furnished
with a loose cover ; this forms the condenser. A small pipe and
cock in the steam-pipe deliver steam through a small orifice
nfar the steam-pipe into arothir pipe, throi'gh which it passes
itto the condensing water. An .igitator and a >on-iive ther-
momeier are provided in the condenser. F< r weighing the
amount of steam condensed, ihe whole condenser is suspended
from a h)dro tat, «hich permits extremely accuraie deiermina-
tion of any chat ge of weight. The hydrcstai i> ba anced by
weights till the pjinter is at a fixed mark b; fore and alter con-
densing the steam. The condcn'-ing mi tliod, the author said,
is .'tri tly accmate in principle, but dilTicult to larry out in a
satisfactory manner. In order toovtrcoire the e ditficuhies a
method oi cortmuius condensation h,Ts been in ruducid. By
this steam and ci>ld tkatcr are both supplied a' a constant
rate, and the condenser acquires a steady tempnature, which
can be very accurately observed. .\ diri^ram of a continuous
injection condenser was shown en the wall of the tl eatre. Steam
passes from the stcam-pif e to a small injector. The condensing
water is drawn from a tsnl:, and the mixed water andomd nse.l
steam are discharged irto another tank. The two tanks are
placed on platform weighing machines. Two thermometers give
the tempi rature of the condensing water (the water used for
condensing the steam), and of the mixture of condensed steam
and condensing water. The difference of the tclal weight in
the two tanks, alter any interval ol time, is the sicim condensed
in that time.

K superhealing method, which was introduced about the year
■ S90, by Mr. G. Uarrus, was next referred to by the author.
The s'lam to be ie-t«d is passed ihioogh an inner chamber
jacketed by superheated steam. The sample of steam lo be
tested wa< thus dried and supeiheatid at the expense of heat
borrowed from the jacket. To avoid measuiing the steam, an
attempt was made to secure that equal weights oi steam passed
through the inner chamber and through the jacl'Ct. In th.it
case the wetness of the steam can be calculated from observa-
tion of the Icmperalutes only. The method, the author said, is
accurate in principle, but appears to be difficult to carry out
satisfactorily.

The wire drawing calorimeter was next descr.bed. This and
the separating method the author considers most neatly fulfilled
the necessary conditions requisite for iiieasuirng the quamity of
moisture contained in steam. This c-ilorimctcr consists of
two chambers, steam passing from the first lothc second through
an aperture Vii inch in diameter. The full steam ]>ressurc is in
the hist chamber, and the pressure in the second diflers litl'e
from atmospheric pns-ure. Thermometers give the tcmpeia-
ture% in the chambers (which are protected from radiation), and in
this way the quantity ol water present in the steam isesiimaled.
The steam is allowed to flow through ihe app.iratus for twenty
minutes or more, when tVc ictrperaturcs become nearly steady.
No weighing is required, and temperatures only have to be
observed. The obscrvaiions can be continued as long asdcsircd,
so as to otita n a mem value for the dryness fraction rom a con-
siderable quantity of steam. If the steam is very wet, the tem-
perature in the second chamber falls to about 212 , showing th«t
wire-drawing to atmospheric pressure is insufficicrit to dry the
ileam. Practically the instrument cannot be used if the wet-
ness e»ceedi the valuci given in the following table, Ihe
presiufcs being in lbs. per square inch, and the atmospheiic
pressure being assumed at \\"j lbs.

Initial [rciture loiiial preft«iirc Initial temr«ra-
(atxolulc). (gau^e). tura !•.

29V • IS'2 - 250°

672 525 ... 300°

«35'' • • '234 •• 35"°

2477 2330 ... 400°

Two conrlit ions arc nrccs ary for accuracy in using this method.
The second chamber must be large enough for the eddies lo die
out be'orc the steam leaves ihe chamber. Radiation must be so
f.ir prevented that the steam in the chamber is not sensibly
cooled. A calorimeter by which the separating and wirc-
ilrawing mithoiU were combined was also explained ly the
author. This ii the globe calorimeter which is a well-arranged
apparntu*.

The Camming lapethcating method was also described. A
vessel is filled wiih the steam lo Ire tested, and then heated by
a jac'iel. As it is healed, the rise of pressure in the inner
vesiel is oViscrvcd, the volume being conrlant. So long as the

initial wetness

per cent.

o-So

2-44

4-21

613

steam is moisi, the pressure will rise with the temperature
according to Ihe law lor saturatcel steam. The moment all the
moisture is evaporated, the r.ite of rise of pressure with tem-
perature will become much slower.

The well-known salt test was next alluded to by the author.
This, however, he pronounced lo be incorveniert and unlrust-
worihy, excepting perhaps in the case of .\ boiler subject to
marked priming action.

The general conclusion drawn by the author was that the
wire-drawing calorimeter without separator is the most con-
venient .ind accurate for steam with less than about 2 per cent,
of moisture. For steam containing more moistuie, the separat-
ing calorimeter without wire di awing apparatus is accurate
enough and convenient. The use ef the separator and wire-
drawing calorimeter combined is more troublesome, especially
if, as is desirable, a condenser is also used lo determine the
amount of steam passing through the separator. In cases
where there is much priming, it would seem best to take the
whole of the steam ihroui^h an ordinary steam-separator,
measuring ilie amount ef water trapped, and then to test by a
wire-elrawing or separating calorimeter the dryness of the steam
after passing the separator. With priming much of the water
probably flows along the bottom of the pipe, ami it appears
impossible that a sample can be obtained containing an average
proportion of steam and water. It is recommended by Prof.
Carpenter that the sample of steam to be tested should always
be taken from a vertical, not from a horizontal steam-pipe. No
doubt there is rather more tendency for water lo flow along the
bottom of a horizontal pipe than down the sides of a vertical
pipe; but merely taking steam from a vertical pipe does not
ensure freedom from error, especially if the amount of moisture
in ihe steam is considerable. Variations in tests for wetness
are doubtless often due lo the difficulty of getting a true average
sample of steam : and it would seem that errors are generally
in the direction of under-estimating tli'^ amount of moisture.

A long and interesting discussion, which was adjrurned from
Ihe Thursday until the Friday evening, was held on Prof.
I'nwin's paper. The chief point touched upon was the nr.ethod
lo be adopted in gelling a true sample of steam for analysis.
This undoubtedly is the great difliculty that has to be overcome
before a satisfactory method of determining the amount of
moiilure in steam can be arrivid at. The majmity of speakers
were of opinion iliat water entrained in the steam would hang
to the sides of Ihe pipe, and a gooel many suggestions were
made with a view to shifting the collecting nozzle over the whole
area of the cross-section of the pipe, or else lo give such an
orifice to the nozzle as would cover a large part of the pipe
area.

In his reply to the discussion, Prof. Unwin explained that
this did not seem to him Ihe true light in which ihe problem
should be regarded. With steam rushing through a pipe at
hit;h speed, eddies would I e set up which would be sufiicient to
thoroughly mix the sleam and water so that there would be a
fairly homogeneous mixture. The Iruc difficulty arose from
the checking of the velocity of the steam at the collecting
orifice, an action which resulted in water accumulating so that
an excess of moisture was shown in the sainirle drawn ofT". In
order to overcome this, he had devised a collecting nozzle con-
sisting of a bent-over tapered pipe, Ihe orifice of which was at
the small end, and was pointetl towards Ihe flow of steam. By
adopting the necessary dimensions for the collecting nozzle, the
steam collected would not be checKcd in velocity at the cedlect-
ing orifice, and therefore moisture would not be deposited at
that point.

Captain Sarkey's paper was ore of corsiderabic length, and
alil ough dealing with one 1 oini only of engine design, was of
great interest '■ engineers. It was illustrated by a large num-
ber of diagrams hung on the wall of the theatre. Without these
it would b; extremely diflicult 'o give a fair idea of the course
of reatoning followed by the aulfor in discussing the nrerits of
Ihe two systems of governing engines. The pa) er, as Ihe author
said, was an elaboration of one sect Hn of a paper contributed lo
the Institution of Civil Rnginecrs by the late .Mr. Willans.

.Speaking broadly, it may be said that the author's opinion
was lira', the popular verdict in favour of variable expansion
governing may for many purposes be accepted, yet its advan-
lages were commonly much overrated, and in some cases it had
no aelvantage at all.

It would be impossible within Ihe limits of our report to trace
out the respective merits of Ihe use of Ihe throttle valve and

NO.

1320, VOL. 51]

February 14, 1895]

NA TURE

379

automatic expimion gear, under the xaxaf cinditimi of work-
ing which the au'hor suppos s ; and as the diJica-ision on the
pap:r was adj lurned until the next micting, we nj ly leave the
subject for the present.

The summer meeiinji; of this Institution will be held in Glas-
gow this year, commencing Tuesday, July 30, and concluding
on the foil jwing Friday.

THE ADVANCE OF TECHNICAL
EDUCATION.

T^HE present slate of technical education in England is, on
the whole, satisfactory iVom the scientific pmnt of view.
The authorities having the fundi arising fiom ihe Customs and
Excise Act under their control, are bi-ginning to see that in-
struction in the principles of science is by far the most
important of the requirements. They are also coming
to recognise thai immediate result-: cannot be expected from
their work — ihat they are laying a fiunlation raiher than erect-
ing a complex e litice. Tne Technicil I is'rncuon Comni'tees
who have not sufficiently realised thi-i, will find ihat they will
have to materially modify tfieir at jirescnt too ambitious
schemes, postponing much of the in-Jtruc ion in subjects of
technology until a more thorough acquaintance *ith the funda-
mentil princijjles of science underlying all such purely technical
education has been provided, for it is only liy such means that
the stability of iheir edu.;aiional sap-rstructute can be en-ureJ.
There are no groin 's, therefore, for taking a pe-simi'tic vie*
of the future of technical instr iction. One of the mos' gruiKy-
in" signs of development is the large nu iitier o' Si:holarship5
now awarded, and tlie increise in the number o^ c •mpititors
for thetn. Tne current number of the Record ol Technical and
Secondary Education ^ets forth in detail a statement as to the
scholarships and exhibitions actually awarde I, durin;; the year
1893-4, by Count/ an 1 County Uoroug 1 C ■uncds. This raoit
valuable Keinm siows the number ol schcdar.tiips an 1 e<hibi-
tions awarded ; the vilu : and length of tenure ol t'le award-; ;
where held; conlition^to be fulfilled by t tie candidates ; the
etamining bodv, and the subjecis of examination. Subjoined
is a summary of ihe informatiun.

Scholarshins ani
Exhibilions.

Scholarships and Exhibitions No. of
tenable at Councils.

(1) Technical, and Science

and Art Schools ... 36 .

(2) Secondary Schools ... 37 .
(3I Universities or Inililu-

tionsof University rank 28
(4) Short cjurses of instruc-
tion 25 .

Nu liber
awarded.

Total yearly
value.
i.

3456 ... 10,620
1789 ... 20,409

362

6,783
3.825

6168 41,637

Sixty individual counties and county boroughs are represented
in the above summiry. Two oth -rs, Demy and Sheffield,
allocate respectively ^325 and ,,^1000 annually to sc'iolarships,
and taking thcie into considera'ion, it appears that the total
sum ex])jDded for the promotion of technical and secondaiy
education by scholar-,liips, during the year ending March
1894, was, in round number;, ^^43,000. But this by no means
represents the limits of expend ture under the scholarship he. id.
It does not t.ake the renewal of scholarships into a.count, and
there are still seven local authorities whose scholarship schemes
have not come into operation. Also, the scholarship schemes
will unloabtedly be fur. her developeil as the work goe> on ; in
faC, it is esi mated ihat before vcy long as much as ^^30,000
will be spent annually on scholarships by the London Technical
Education Board alone. Truly, these are halcyon days for ihe
promising young student, however humble his state of life
may be.

As to the values of the scholarship?, they vary from a few
shillings, as a fee for a short course of instruction, to ^"60 a year
tenable for three years. The lower limit of age is usually
thirteen, and the higher, tiventy-five, though we sei ni
reason why such a maximum age should be made absolu e. In
some caies, the income of the parents of competitors must
not exceed £,ifiO a year, but in others — London is ihe most
notable instance — the parents of competitors for junior scholar-
ships must not be in receipt of mire than ^^150 a year.

NO. 1320, VOL. 51]

Another important statement in the current Record shows the
plans for promoting tech deal and second iry education in each
of the counties and county boroughs of Knglmd. From this it
appears that, of the no locil authorities in England, 96 are
giving the whole, and 13 part of their grants to educational
purposes. Preston is the reinainin; autiiori y, and it devotes
the whole o' the g ant available— about ^"i6oo per year — to the
relief of the boiough rate. But it should be siated at
once, that Preston possesses a well-endowed " Harrb
Institute," where technical education has been carried
on for years. The total amount avadible by local
authorities is about ;f 744, 000, of which about ^^ 144,000 is
diverted to the relief of the rates, leaving ;if 600,000 lor expendi-
ture on education. We are .'-anguine enough to brbeve that,
before long, most o^ the ^144,000 at present devo'ed to general
county pu poses will be exi'cn 1 d in advancing technical educa-
tion. L'lnlon alone is lesp m-ible for ;^ii4,oooof this mis-
applied balancf, bat as its educaiimal scheme matures, it will
doubtless absorti the wh >le am lunt ava lable. It is to be hoped
that the authoiities applying the remaining /'30,ooo to rates,
will soon see how deirime ital their action is to their own
interests.

In this connection it is nece sary to ondemn the application
to rates of any unexpended balance of the grant available. In
every county and ouniy bo ough there are persons who utterly
fail to reali-^e that the intecsts of science are the intere-ts of
industry. To them, immed ate advantages in the shape of a
minute reduction of the rates, appeals far more than prospective
developments ol our naiionil industiie^. Had such people the
control of affairs, technical instruction would indeed be curtailed
wi'hin narrow limits. Fortunately, they represent but a small
minori y in the County Councils ; nevertheless, their influence
is occasionally manifest. Ever since the Technical Education
Acts came into fo ce, attempts have been made here an 1 there
to use fir geneial county purposes the funds available and neces-
sary for education. But if the w uk is to be successfully carried
out, it is essential that the Technical Instruction Committees
should have entire control ol the grants allocated to technical
education. There is far too much uncertainty about the grants
even now, and the County Cou cils which are inclined to exer-
cise a veto as to the destination of th-: surplus funds of their
Technical Education Committees, will soon find that self-
respecting members ol the Comm ttees will retire from the work.
Recently, ho.vever, one or two Councils have shown their
incapacity to uniers:and the magnitude of the problem before
them, by voting the unexpended balance of their grants to the
relief of rates. Tnis action is tantamount to declaring that the
funds at the disposal of the Com uittee are in excess of what is
required ; whereas, it is hardly too much to say that addi.ional
secondary schools are needed in almost every county and county
borough in England, only to mention one way in which the
money might be expendeL For the balance to be diverted
fiom education is bad enough, but no great foresight is needed
to see that, once the action has bien taken, there is no knowing
where or when it will stop. Perhaps the county of Hampshire is
the most notable instance in which a County Council has crippled
the work of its Technical Instruction Committee. In November
last according to the Southampton Times, the Council resolved
to appropriate, for general purposes, /'6000 from the surplus
funds which had been accumulated by the Technical Instruction
Committee with the idea of evenually using it in educational
developments. Without taking the views of the Committee into
consideration, the Council appears to have calmly confiscated the
balance resulting from economical administration, and by sodoing
not only discouraged careful expenditure, but in one fell swoop
rendered the Committee powerless to deal in the future with
matters which alone coul J be met by exceptional means. Surely
it is not too much to expect a Council to have confidence in
the ability of the Technical Instruction Committee, and to allow
it to know is own needs. At any rate, a Committee whose
opinion is disregarded must soon losec mfiJence in itself. It is
a matter for congiatulaiion that County Councils generally have
not treated their Committees in the same way as the elect of
th- county of Hampshire.

One of ihimoit refreshing repor s we have seen for some
lime has reccnly been issued by the Derby -hire County Council.
The report is satisfactory, not so much on account of vvo k
accomplished, but beciuse it affords ev dene; that the Committee
seems to have been brought to a good understamling as to what
technical instruction should mean. One of the chief difi5cultie

iSo

NA TURE

[February 14, 1895

niL-t with in most parts of the coanlry arises from the suspicion
with which the spoilt " practical man " regards the whole scheme
of edacation designed to benefit him. No class harbours this
p- ' - -e than farmers ani their labourers. .-Mmost every
1 V compliins of the apathy, or the opposition, of

a^: ;o the extension of knowledge in the scientific

priDCipici of agriculture. When the Derbyshire Committee
approiched this branch of their work, thev hesitated to establish
a/riculture classts under the auspicc-s of the Department of
Science and Art, because such classes arc open to undesirable ob-
jections from this section of the community. In the first place,
there is an appearance of attempting to tench '• farminj; " in the
lecture-room, and secondly, the teachers who are qualified to give
most of the information contained in the Science and Art syllabus,
are usually not actually engaged in the agricultural industry
itself li )th these difficulties have been cleverly met by the
Committee in this way ; — " In place of the ' Agriculture ' Classes
of the Science and Ait Deimtment, the Committee are anxious
that the students in rural evening schools shall go through a
course of elementary science, which shall be of a very simple
bat thoroughly scientific nature. It is intended that the s'udent
shall be taught by actual experiment, and shall thus come to
apprecijte that the results of science are not fanciful, but are
con:lusions drawn from a study of actual facts. The phenomena
studied in this coarse of lessons are of n general character, but
are also largely chosen from the domain of agriculture, so that
without any suspicion that the schoolmaster is attempting to
leich ' farming.' the student learns a number of principles
which cannot fail 1 1 aOTect him in practice.

"The great merits of th's scheme of teaching elementary
science in rural evening schools in |>lace of starting Science and
Art Department 'Agriculture Classes are that the students
are kept together year a'ter year, studying other subjects which
go to make up the curriculum, the liienientary Science course
extending over two or three years, so that a first set of pupils is
ready when the older ones have passed through ; and further,
there is no suspicion of teaching what can only be learned on
ihtfarm."

The scheme is very attractive, and good results may be
expected from its a|<plicaiion in Derbyshire. It enforces the
fact thr.'. a kn iwled^e of the eUinentnry princiides of science is
the only sound basis upon which to build courses of technology.
The county of Derby is more dependent upon the mining
industry than on any other: therefore its organisation of instruc-
tion in mining deserves a word of remark. It attempted to
provide the instruction by means of courses of lectures delivered
in a certain number of pit villages, but the results were hardly
successful. The leaching was afterwards given by local mtn
who had practical kno*leilge of mining, and some acquaintance
with collateral branches of science, and this scheme was more
satisfactory than the former. The point to ije borne in mind
in all such cases is that chemistry, steam, geology, some
branches of physics, and mechanical drawing should form a
part of the education of every mining student. With refer-
ence to local teachers, a word may be necessary. There
is, of course, a tendency in many districts to p.ilronise
local ability, but it should always be botne in mind that the
local man is not of necessity the man who will do best. In the
expenditure of public money, it ought to be a guiding principle
that the best teachers available by adverliiemcnt and good
salaries >hould always be selected.

The evergreen complain; of Technical Education Committees
linds expression in the report from iJerbyshire. In connection
with the subject of evening continuation schools, we read :
"The Comniiilee hive found that one of ihe great dilticullics
which Ihe ordinary student experiences in receiving instruction
in every kind of technical subject is the lack of sulhcient pre-
liminary knowledge. His elementary school education has
very lar^fely leaked away, instead of having been continued to
the point giving caiy compiehension of .scientific principles ami
problems. Thii iinplie* that llic national expenditure on
elementary education is very largely wasted without some
supplementary scheme by which the instruction given shall be
conserved and continued until the student is old enough to grasp
ils importance." This puts the wh'de matter in a nutshell.
When the average boy leaves the elementary school, at about
fourteen years of age, he legaids his education as completed, with
the result that he has no iniercsl whatever in schools or classes
of any educational value. Committees nui-! not hope to attract
the ma;oriiy of working lads into evening c 'n'inualion schools,

NC. T320, VOL. 51]

however diversified their prospectuses may be. Only here and
there can pupils be found who have begun to see the depths
of their ignorance, but these are the minds to nurture, and for
their benefit systems of evening-classes should be constructed.

Before the era of the County Councils, the principal means for
the spread of instruction in elementary science was undoubtedly
the classes of the Science and Art Department. Testimony is
borne to this in the report referred to. We read :

"It has been the custom in many educational quarters to
criticise and condemn the methods of that Department, and to
create an impression that but little good has been .accomplished.
The contrar)' of this is undoubtedly the case. In all manu-
facturing centres it will be found thtt there are numbers of
persons applying to every kind of industry scientific princi|ilcsand
knowledge gained at Science and Art Classes, and which could
not have been gained anywhere else during the last thirty-five
years." The Department is very well able to take care of itself,
but this statement of fact may be profitably considered by those
who disparage its usefulness.

If there is one thin^' our educational system lacks more
than ano her, it is proper facilities for secondary education.
Recognising that a good education in a secondary school is
the only means by which the highest branches of technical
instruction could be approached, the Derbyshire Committee
ofl'ered for competition sixty scholarships tenable at secondary
schools. After Ihe awards had been made, it ».as fou d that
only six out of the sixty successful candidates chose schorls in
the county, and that there was only one school in the adminis-
trative county av.ailable for the girls who had won scholarships.
An inspection of the Grammar Schools, and similar institutions
in the county, with a view to determining their cduca ional
conditions and needs, revealed a general want of proper equip-
ment ; indeed, only one out of nine secondary schools had a
chemical laboratory. Derbyshire is certainly not alone in this
deplorable stale of things, which it will lake some years to im-
juove. The fact tha' the defects in our educational ^ystcm are
being exposed, and that attempts .are being made to meet them
fairly, is a clear promise of progress. If ihe Technical In-
struction Committees had done no more than reveal the in-
efficiency and insudiciency of scientific instruction in the counties
of England, they would have furthered the interess of science.
But as they have also helped to organise and increase Ihe
facilities for such instruction, ihey have worked in no mean w.ay
for the extension of nitural knowledge. En-ouragement and
friendly guidance is all that is reipiired to render the work even
more valuable in tlie future thin it has been in the p.ast.

R. A. CiREC.ORV.

SCIENCE IN THE MAGAZINES.

T7IRST in importance among the contributions lothe February
magazines is a collection of opinions on forest preserva-
tion, published in the Cenliiry. In response to a request from
the editor of that magazine, a number of persons interested in
arboriculture sent iheir views as to the general need of a
thorough, scientific, and permanent system of f ircst manage-
ment in the United Stales, and specifically as to the plan
suggested by I'roC C. .S. Sirgent, which comprised the follow-
ing features : —

(1) Forestry instruction at West Point ; the esl.ablishment of
a chair of l-'oreslry at the United Slates Military Academy, to
be supplemented by practical study in Ihe woods and by per-
sonal iiispeclion of foreign systems of forestry.

(2 All tvpcrimental forest reservation ; the purchase on the
Highlands near West Point, or elsewhere, of a small territory
lor the use of the proposed new branch of instruction.

(3) Control by educated officers; the assignment ol the best
educated of these officers to the supervision of Ihe forest
reservations.

(4) The enlistment of a forest guard : a body of local
foresters, lo be specially enlisted for the purpose ol carrying
out the principles ol forestry thus taught. .

The experts consulted agree in the opinion that the United
States needs a thoroughly .scientific and permanent system of
forest management in the interests of the people of tiday, and
of future generations. Hut the general feeling seems to be that
the management of ihc forests should not be placed under any
military organisation. As lo the suggestion to incicase the
(.urriculum of the U.S. Military Academy so as to cover

February 14, iJ^95j

NA JURE

instruction in forestry, it is rightly pointed out that a course in
forestry which is merely an adjuntt to a military education
must fail to produce the highest efficiency as foresters in the
officers who lake it. " Adequate training in so large a subject,"
is remarked by one of the cone-pondents, " can be reached
only by long and undivided attention." And further, as Pro'.
Cleveland Abbe say?, " the aits of waifare are a special appli-
cation of the arts of peace, and it is a perversion of the military
school to make it a rival of ihe civilian schools of tngineering,
chemistry, forestry, &e." The general opinion appears to be
that for ttie preservation and management of forest rest rv.it ions,
a permanent body of foresters is required, but it should be
composed of practical woodmen who have devoted some years
to the study of foresiry. If "e may express an opinion upon
the maiter, to us this seems the only vitw which can have any
support from scientific men. To make forts ry a subsidiary
branch of a military education, wou'd be to estatlish scant pro-
vision for the science. If merely the protection of forest
reservation be aimed at, Prof. .Sargeni's plan probably offers
the ea-iest way i/f obtaining it ; but if the forests are to be
devel ped, a foret school, where foresters can be scientifically
trained, becomes e-seniial.

Another contrihuiion to the Ctiiliiry is the sad story of the
death of Emin Pasha, told by Mr. R. Dorsey Mohun, the
United Stales agent in the Congo Free State. In A|>ril of last
year, Mr. Mohun arrested and took the confessions of the two
Arab slaves, named Ismailia and Mamba, who had killed Emin.
The following is a brief statement of the melancholy facts : — In
the Unyoro couniry, to the west of the Victoria River, Emin
came upon an Arab camp, under ihe command of Said ben
Abedi. He expressed his iniention of making his way to
Kibonge, about eighty miles souih of Stanley Falls, and it was
arranged that his force, numbrring about 150 people, and Said's,
should travel togriher. On October 5, 1892, Emin and Said
arrived at the small village of Kinena, which lies 150 miles to
the north-east of Kibonge. Said thtn went on to inform the
Kibonge chief that the white man was coming, Ismailia and
Mamlia going wiih him. About tweniy da)S laler, Mamba
returned wiih a letter to Emin, saying that safe conduct to
Kibonge should be given ; but the Kibonge chief sent another
letter to the Kinena chief by Ismailia, containing instiuctions to
kill Emin. The Pasha was induced to send his men into the
plantations on a pretext, and while they were away he was
murdered, and his head sent to Kibonge. This appears to have
occurred on ihe morning of October 28, 1892. Emin's head was
sent by Kibonge to Munie-Mohara at Nyangwe, the reason
being, Mr. Motiun thinks, that Kibonge wished toshow that he
could kill a wtiiie man as well as Miiiiie-Mohara, who had ordered
the destruction of l^iodister's expedition fivi- months previously.
"Not the .-lightest suspicion," says Mr. Mohun, "attaches to
Said ben Abedi of having had any connection with E-nin
Pasha's death, which is regarded by the .Arabs wiih whom I
have taRed as a siupid error on the part of Kibonge, «ho com-
mitted the crime sim^jly to place himself on the same level as
Munie-Mohara, who had killed Ilodister. I do not believe,
either, that Tippoo Tib had any hand in the crime, which must
have been as great a surprise to him and to his son, Sefu,
and his nephew, Kachid, who was ihe Governor of Sianley
F.ills, as it was 10 us." An article on " New Weapons of ihe
United Stales Army," also in the Century, and the eighteen
pictures and diagrams which illustrate it, will interest many of
our readers.

Dr. Charles L. Dana writes on "Giants and Giantism," in

tf'iur. Two years ago a man nearly seven feet in height,

, J assessing very large feet, hands ami head, came under his notice,

and was found to be a victim ol the peculiar disease known as

acromeg.ily. Ttie man died from the effects of his disease,

and a portion of the brain — the pituitary body — was then

found to tie enlarged to many times its original size. This gave

support to the idea that en'argcment . f ihe pituitary body

is the cause of ;he giganiic giowih of the extremities in

acromegaly, and that giants ^.cnerally are not sini ly frraks,

but victims of a nervous disorder. The skeleton of the famous

Iiish giant was studied some time .igo by Prof. Cunningham,

1 and found to be characteristic "f a case of aciomegaly, and an

1 examination of photographs 1 f nearly all the living giants now

j on exhibiiion leads Dr. Dana to believe thai about one hall ol

them are acromegalics. Accoiding lo Dr. Dan^, "exii.iordinary

size is a disease, a neurosis of nuiriion, rather than a chance

(disturbance ol developmcDt. . . . It is possible by certain kinds

NO. 1320, VOL. 5 I "I

of gland-feeding, to increase ilie sta'ureof dwarfed persons very
rapidly. There is, for example, a gland called ihe 'ihyroil
body' lying in the neck, the juice of which, when fed to certain
kinds of dwarfs (coclins) causes iheni rapidly to grow. Ex-
periments in feeding anim.ils and n en with the pituitary body
are now in progress."

"The Method of Oganic Evolution" is expounded by Dr.
A. R. Wallace in the Fortnightly, the article being really
a criiical and adverse review of Mr. Bateson's views on
disconiinunus variation, as set forth in "Materials for the
Study of Variation." A second article en discontinuity In
evolution, dealing with the theories advanced by Mr. Galton,
will appear in a future number.

A posthumous essav, by Dr. G. J. Romanes entitled
" Longevity and Death, ' appears in the current number of The
Monist, to which it was sent by Prof. C. Lloyd Morgan.
In it an unpublished essay, written in 1875, is quoted, in which
occur the following passages : —

"Those sfecies whose ancestral types have frequency been
required to vary would have gained much during the history of
their descent, by having their constituent individuals shoit-
lived; for in this way a comparatively great number of
opportunities would have been afTorded for the requisite
variation to arise : in other wcrds, a comparatively great
number of variations would have occurred in a given time.
Hence it seems natural to infer that it is in the power of
Natural Selection to atTect \\if: curtailment o{ indivieiual life,
wherever such curtailment would be of advantage to the
species, that is to say, vi\\ex^\ti Jlfxibility o( t)pe is required.
Of course, length of life is not the only factor which
determines flexibility of type. There are at least three other
such factors: (i) the period at which puberty sets in, (2) the
num'ier of times the individual breeds during its life-time, anel
(3) the number of young which it bears at each timeof breedirg.
Nevertheless, it is true that the length of life is a highly important
factor, because, if the individual is shoit-lived, it becomes a
necessary condition to the continuance of the species that parturi-
tion should be frequent. Or, more generally, there must be more
or less of a direct proportion between the potential longevity of
eveiy species and the frequency of parturitions characteristic of
that species — if not also of the number of offspring in each.
Now, as Mr. Lankester has pointed out, there is, as a matter
of fact, a highly remarkable correlation between potential lon-
gevity in the individual and frequency of parturition, as well as
of numbers constituting the liiter which are distinctive of the
species. This correlation he attributes to generative expendi-
ture acting directly to the curtailment of life ; but in holding
this view, I suspect that he is mistaking cause for effect. I do
not think it is generative expenditure which causes curtailment
of life, but that it is curtailment of life by Natural Selection
which causes the high generative expenditure within the
lessened period. It is as though all the conditions needed to
secure tlexibility of type were adaptively associated in these
species which have survived in a comparatively fluctuating
environment. Moreover, it is worth observing that all the
organisms to which Mr. Lankester ascribes a practically un-
limited potentiality of life, are organisms which, as far as we
can judge, must always have been exposed to uniform con-
diiions of life."

In addition to this. The Monist contains an article by Dr. E.
Montgomery,who attempts "first to gain a scientifically justified
and logically consistent physical basis, upon which a natural-
istic conception of vitality can be reared ; and thenj to show to
what special physical conditions vital activities and vital organi-
sations owe their existence." We also notice a metaphysical
paper on "The Natural Storage of Energy," by Mr. Lester
F. Ward.

Pascal is the subject of a paper, by the late Mr Waller I'ater,
in the Contemporary, but his scientific researches are not dealt
with. Towarils the end of the notice, there is a note on the
influence of imagination on his work. It is: "Hidden under
the apparent exactness of his favourite studies, imagination,
even in thorn, played a large pait. Physics, mathematics, were
with him largely matters of intuition, anticipation, precoc ous
discovery, short cuts, superb guessing. It was the inventive
elemert in his woik and his way of putting things that surpiised
those best able to judge. He might have discovered the mathe-
matical sciences for himself, it is alleged, had his father, as he
once had a mind to do, withheld liim fiom instruition in them."
.\ bright and sensible paper on " Nervous Diseases and Modern

;S2

NA TURE

[February 14, 1895

Life" is contributed to the same review by Prof. Cli6rord
Allhalt. There is also a faper of iniere't lo physical geo-
graphers, its tiile being "The Evo'ution of Cities."

The current Quarierly KtZ'icv has among its anicles a sVetcb
cf the history or the O ilnancc .Survey, wherein we read "the
5cope of ihe urderLikinq excrcd-i any proijramnne heretofore
atlempied ty any Government, ihe moHe anrl style of its fxecu-
tion are second lo none, either fiom a scifntific, artistic, or
iililitaiian point of view, and ihe C'•^t of the wnrk, s'roke
for strole, i- prol ably lower than that paid by any other nation
for a ^imllar I'urpose. " Pro', Huxley's collected essays, and
"ther works, are reviewed under the title " Prof. Huxley's
Creed," and in the article " England in Egypt," the irrigation
of Egjpt, and the construction of the Phila; dam, are noticed.

The Ktliquary and liliistialed An/nrohtgisl is rich in good
illustrations. Among the articles we notice an account ol the
exploration of a Hunni>h cemetery at Czika, near Buda-Pesth.
Parts of a number of skeletons have been found, and a complete
-kcleton of a woman, six feet thue inches in length. Weapons,
stirrups, earthenware v(s*els, and various ornaments have also
teen found. "The Burring of the CUvie," a ceremony still
carried out on the last night of the old year at Burghead,
in the north of S''otland, is described by Mr. H. W. Young.
The custom appears lo have come down from the most remote
.ages. The natives of Burghead assert that it is a Druidical
W' r>hip, while Mr. Young believe^ it to be simply a revival of
the worship of Baal — a remnant of that great fire worship
which prevailed over the whole world as known to the ancients.
In the notes is an illustiaiion of the ancient Egyptian tomb in
the island of Elephantina, discovered and explored by H.R.H.
the Crown Princess of Sweden and Norway, and an illustrated
de-ciiptinn of the re-erection of iho^e interesting pre-hi-toric
moouiuents, the Dartmoor menhirs. Recent investigations
have yielded some evidence which connects these stone-rows
with the Neolithic pcrriod.

.\ passing notice must suffice for the remaining articles on
.scientific subjects in the magazines received by u«. Good Words
c miains Sir Robert Ball's concluding paper on "Sir Isaac
Newton," and a brief paper "On the Anti-toxin Cure for
l)iphihciia," by Dr. \V. J. Fleming. A visit to the tomb at
iJ.ishur, where the jewels of an Egyptian princess of the
Twclfih Dynasty were found las: )fai, is describe I by Mrs.
St. Loe S rachey in the jValioiiat. The Humanitarian has an
article on " The Prevalence ol N'tvous Diseases," by Dr. S.
.\lthaus. "Some Curiosities of Modrrn Photography" are
brought together by Mr. W. G. FitzGeiald in the Strand
Ma^azinf. The illustration he gives ol an image photographed
through the eye of a beetle is, however, quite eclipsed by a
photograph taken by Dr. Siiitta through the lenses of ihe
comitosite fye of a water-' ccil*». and reproduced in Kn<nvUdge
for July 1894. Mr. Grant Allen contiibues a rhapsody on
quails to the Enj^liih Itluitralel. Cha.mbers s Journal contains
iu nsual complemeni of readable arlicles on scientific topics.

UNI VERS/ TV AM) E D UCA Tl ON A L
INTELLIGENCE.

Oxford. — In a Congregation held on Tuesday, February
12, the amrndmenis lo ihe proposed .S'aiuH on Rrseaich
Dcgieen came under consiilcration. There were sixty-thne
amen'iments, and of ihc«e onlv fourteen came under considera-
tion, as the debates on some of them were of some length. The
fir>t amendmrni, pr 'po cd by ihe Provost of Oiiel, and
seconded by Pnf. Odiing and M'. .Sirachsn Davidson, pro-
posed that the Decree of Bact'clor o( Arts should be substituted
for ihe propo ed Degrees ol Bachelor o( Letters and Bachelor
of .S.;ieiice. After a prolonged debate the amendment was
negatrverl by 137 voles again-t 33.

An amenrlmeni by Prof. Case, defining ".Science" as in-
cluding Malhemaiic", Natural Science, Mental and Moral
Science, was carii-d by 137 votrs againi 34. An amendment,
proposed by Mr. C. C^nnan, of Trinity College, and seconded
by Mr. Bourne, providcrl that ihe supeivision rif ihe candirlales
for Research Degrees should be ve-leil in Ihe Hoards of Facul-
ties, ins'ead of in a »j»ecial Delegacy as proposed by the Statute
under con.ideration. This amendment was carricil by no
voles againM 49. Another amendment, by Prof. Holland, which
propoieil that canrlidatcs for Research Degrees, not being
already Graduates of the UniveiS'ly, should have obtained a
degree in some other University, was rejected by 107 voles

NO. 1320, VOL. 51]

against 39. The other amendments were either consequential
on those already mentioned, or were of a formal character.
The fur her consider.ation of the amendments was fixed for
Thursday, February 21.

Cambrioce. — The Sedgwick Prize in Geology has been
awarded to Mr. Henry Woods, of St. John's College,
Demonstrator in P.daeontology. The subject proposed for ihe
prize of 1898 is "The Glacial Deposits ol E.ast .Anglia." The
essays are to be sent to the Regisirary by October I, 1897.
Candidates must be Gradiiat-s of the Un versity who have
resided sixty days during the preceding twtlve months.

Mr. M. Laurie, of King's College, has been appointed
by the Special Boatd for Bidogy and Geidogy, lo occupy Ihe
University's table in the Naples Zoological Mation, for three
months from March I.

A course of lectures in .\nlhropilo.;y, with practical w irk, is
announced by Prof. Macalisier for the Ltnt and E.ister Terms.
The lecturer is Prof. .\. C. Haddon, of the Royal College of
Science, Dublin. The sul jecl of the first lecture, on February
14. at 3 30, is "The Meihods of Amhropology."

The degrre of Sc. D. honoris causa is to be conferred on Sir
William MacGregor, .\diuini trator of British New Guinea, in
recognition of his able contribulions to anthropology and
ethnography.

The following appoinimrnts of electors lo Professorships in
Natu'al Sci. nee anil Med cine are announced. Chemistry,
Dr. T. E. Thorpe ; Plumian of Astronomy, Dr. A. R. Forsyth,
and Mr. W. H. M. Christie, Astronomer Royal ; Anatomy,
Dr. Allbutt ; B tany, Mr. A. Sedj;\vic'< ; Gology, Prof.
Newton ; Jacksmian of Natur.il Philosophy, Lord Rayleigh ;
Downing of Medicine, Dr. A. Macalister ; Mineralogy, Prof.
J. J. Thomson; Zoology, Dr. D. Macalister; Cavendish of
Physic, Lord Rajleigh ; Mechanism, Pro'. Osboine Rejnolds;
Physiology, Mr. J. N. Langley ; Surgery, Dr. A. Macalister;
Pathology, Dr. .askell.

A grant of {^^a from the Worts Travelling Scholars Fund has
b?en made to Mr. P. Lake, o( St. John's College, for the
purpose of investigating ihe distribution ol Trilobiles in Russia
and Sweden.

A Parliamkntary Paper ilealing with ll-c moreys received
by the Couni ils of Coiinncs and County Boroughs in England
and Wales under Ihe Local Taxation (Customs and Excise)
Act, 1890, a"d available for technical education, has just been
published. The following summ.ary slio*s how the moneys
have been expended : —

Aggregate amount received
up to March 31, 1894 ...

Aggregate amount ex-
pended on —
(rt) Technical and Inter-
mediate Education ...
(b) Purpo-es other than
Technical and Inter-
mediate IvUicalion ...

Aggregate amount appro-
priated to Technical and
Intermediate Education,
but remaining unex-
pended at the dale of
Ih'- Returns

Residue not appropriated
for Technical and Inicr-
mcdiaic Education, but
remaining unexpended
at the dale of the Re-
turns

Cr^unlics

(•itlier than

London 1 and

Coiinly

Borouulis.

County of
London.

2.4J9,3"9 1 687,034 3,126,353

1,481,712 27,246 1,508,958
290,508 Coo,034 890,54a

635.933 59.754 695.687

' 31,166

2.439.3'9

166

687,034 3,u6,353

1 j£r%7oo of Ihii amount had been appropriated to County buildings and

Februakv 14, 1895]

NATURE

383

Seventy-one out of the 126 Councils had enpenied on, or
appropriated to, Technical or Intermediate Education the
whole of the moneys they had received from the residue of th;
Beer and Spirit Duties.

SOCIETIES AND ACADEMIES.

London.
Physical Society, February 8. — Annual General Meeting.
—The chair was laken by the retiring President, Prof. Kiicker.
— The Treasurer, Dr. Atkinson, presented his report for the
year 1894. The balance-sheet showed a somewhat larger
expenditure than in previous years, the incrta;e being partly
due to the new system of publishing abstracts, partly to the rent
of rooms and the expenses of tea. The balance in ihe bank
had increased by ahou ^^33 during the year ; but the Treasurer
said that, strictly speaking, the S >ciety had trenched on its
capital to the ex'ent of about i[,}p, and that this would pro-
bably be the last report for some time to come which would
show a balance in favour of the S iciety. The assets of ih;
.Society exceeded its lialiiliiies by /,'2642 os. 51". Prof. C«rey
Foster asked whether it would not be possible, in estimating
the assets of the Society, to make some allowance for the
stock in hand. Dr. Akin^on replied that that had not hitherto
been done, and the diflTiculiy would be to assign a money value
to the slock. The stock of the works of Joule, and of other
memoirs, was of course decreasing, while the sale of the Pro-
ceedings was becoming somewhat greater. As rega.ded the
securities of the .Sicicty, their actual value would be about
j^2O0 or j£^3O0 more than appeared on ihe balance-dieet. Prof.
Riicker said that the Siciety had deliberately enletel upon a
policy of expansion, an t that they must be prepared to find
the expenditure increasing. On the other hind, it was hoped
that by making the S ic e'y more attractive, a greiter number
of persons would be induce 1 lo j<jin. In view of the great
advantages no* enjoyed by members, there had been some sug-
gestion of raising the subicription ; but, in any ca«e, hi thought
that thsy might I )ok forward to the future with confidence.
The report was then moved an! ad'>pted. — The next business
was the election of Offiiers and Council for the year 1895-6,
and Messrs. Rhodes and \'u!e, being asked to act as scrutaiors,
collectel the ba'loling li^ts. — Prof. Carey Foster propj^ed a
vole of thanks to the Lords of the Committee of the Council on
Education, for having allowed the Society to meet at the
Royal College of Science. At the commencement of the
life of the Society, its founder and firs' President,
Guthrie, had obtained permission for the meetings to take
place at South Kensington, and the Society had con-
tinued to meet there until their lejen; migration to
the rooms of the Chemical Society. The vote of thanks was
duly seconded and was carried unanimously. Major-General
Festing then proposed, and Mr. Croft seconded, a vote of
thanks to the auditors, Messrs. Inwards and Trotier. This also
was orried. Mr. Trotter then proposed a vote of thanks to the
letiring Council ; they had shown an energy which was rare in
such societies, and had inaugurated an active and original
policy, which must prove of the greatest benefit to the Physical
Society and to physical science generally. Carried unani-
mously.— Mr. Elder gave notice of a proposed alteration of the
lules, the object being to allow the Council under certain con-
ditions to admit persons into the Society without requiring from
them the usual num'ier of recommendations from members. It
was pointed out that sometimes eligible peison"-", especially tho^e
resident abroad, were unable to enter the Society because they
were unknown to any of the existing members. The motion to
sanction the proposed alteration was put from the chair and
carried, but this decision will need to be confirmed at a subse-
quent meeting, of which due notice will be given. — Mr. Rhodes
then read the following list of the Officers and Council elected
for the year 1S95 0: President, Capt. Abney. Vice-Presidents
who have filled the office of President : Dr. Gladstone, Profs.
Carey Foster and Adams, Lord Kelvin, Profs. Clifton,
Reinold, Ayrton, Fitzgerald, Riicker. Vice-Presidents: Mr.
W. Baily, Major General Festing, Prof. Perry, Dr. Stoney.
Secretaries : Messrs. Blakesley and Elder. Treasurer : Dr.
Atkinson. Demonstrator : Prof. Boys. O.her members of
Council: Mr. Shelford Bidwell, Mr. W. Crookes, Messrs.
Fletcher, Glazebrook, G. Griffith, Pro's. Henrici, Minchin,
Mr. Swinburne, Profs. S. P. Thompson an i S. Young.— Prof.

NO. 1320, VOL. 51]

Riicker then vacated the chair in favour of Captain .\bnev, and
the meeting being resolved into an ordinary meeting, Mr. W.
B. Croft gave " an exhibition of simple apparatus." .\n optical
bench was shown which consisted of a wooden lath of rect-
angular section, furnished with a millimetre scale, and clamped
on to the table, together with three flat woolen blocks, whose
contacts with the table and the lath lefi them only freedom to
slide in a direction parallel to the scale. Another apparatus was
designed for observing anomalous disper-ion. .V cork supported
two rectangular pieces of microscope coverg'ass, which were in-
clined at a snail angle to one another; and a drop or two
of a strong alcoholic solution of fuchsine being introduced be-
tween them was maintained in position by capillary action.
Photographs were shown of Chladni's sand-figure", some of the
forms being of an unusual character. Mr. Croft also exhibited
a polariscope in which the polariser was a thin piece of glass
stuck on to cork by mfans of black sealing-wax, aid the ana-
lyser a plate of touru'aline ; as well as a miniature model of
Grove's gas battery. Photographs of some curious optical phe-
nomena were projected on the screen, including 12-rayed
stars seen on looking at a bright source of light through certain
specimens of mica, and pairs of intersecting or nm-intersecting
circles of ligh', obtained under similar circumstances with
(doubly refractinu) fibrous calci'e. These last, it was suggested :
were similar in origin to the curves obtained by reflection at,
or transmission through, a dilTraction-graling held obliquely.
Clock-springs broken by frost were also exhiriited, each spring
having given way in a very great number of places simultane-
oudy. Dr. Johnstone Stoney said that many years ago he had
published in the Tiansactiom of the Royal Irish .\cademy an
iuvest'g ition of the circles seen in fibrous calclle, and had shown
geometrically that they had nothing to di with the regularity of
the fibrous structure, but were due 10 reflection and refraction
within the crystalline plate. The distribution of the planes of
polarisation round the circumferences of the circles was also
accounted fir by his investigations. Mr. Price said he had
found that when a clock-spring during the process of hardening
was kept in shape by wires, subsequent fracture was most apt
to occur at those places where the wires had been in contact
with the spring. — Mr. Rhodes asked if Mr. Croft had ever tried
Newton's experiment of admitting sunlight between two sharp
edges inclined at a small angle to one another. He had not
been able to obtain the hyperbolic bands described by Newton.
Mr. Croft said he had not tried the experiment exactly in that
form. Captain .\bney said that this experiment had succeeded
very well in his hands. — Mr. S. Skmner read a paper on the
tin chromic chloride cell. He said that his attention had been
attracted to the cell by an account published by Mr. Case, of
New York. The cell had been stated to give no E.M.F. at
ordinary room-temperatures, while it gave a considerable
E.M.F. at 100' C. The author had founi that when the cell
was directly connected up to a galvanometer, there wis no cur-
rent at ordinary temperatures, and some current at I0D° C. ; but
when he ha i measured the E.M.F. by Poggendorff's method,
he had found '41 volt at 15" C. and 40 volt at 97' C. The
cell as o: iginally described consists of a tin plate and a platinum
plate immersed side by side in a solution of chromic chloride ;
when the temperature of the cell is near to 100° C, and the
poles are connected, the following reaction occurs :^

Cr.,Clc -I- Sn = 2CrClj -^ SnCL ;

and when the poles are disconnected and the cell cooled, the
reverse change takes place. The author prefers to use as elec-
tropositive metal an amalgam of tin an 1 mercury instead of a
tin plate, so that when the tin precipitated d.iring cooling falls
to the bottom of the solution, it is redissolved in the mercury,
and the cell has regained its original slate. Wnen silver ni:rate
solution is added 10 chromic chloride, only two thirds of the
chlorine cjmes down as silver chloride, and this has led the
.author to suppose that the pro,)er formula for chromic chloride
is CrCl . Clj. Hence he works out the electrolytic action by
means of a Grolthus chain. Prof. Riicker asked whether a
change t f polarisation would explain the behaviour of a cell at
different temperatures. Piof. Carey Foster a;ked whether the
leversed chemical action on cooling from a high temperature
were accompanied by a reversed E.M.F. Mr. .Skinner said no.
The tin was precipitated throug'iout ihesolutio.i, and not at the
surface of the tin plate, ;o that no E.M.F. of the kind was to
beexjccted. Mr. Applejard thought that Prof. Minchin had
used tin chloride cells with two' tin plates for electrodes, the

3^4

NA rURE

[Febkuakv 14, 1895

Cflls only working when one plate w.T illuminated. Mr.
Trotter wished to know whether heating the cell supplied energy
to it, or simply removed an obstacle in the form of polarisa-
tion. Mr. Skinner thought that hea'ing acted by removins; an
obstacle. Caplain .\bney : .\nd so djing work.

Paris.

Academy of Sciences, February 4. — M. Marey in the
chair. — The proceedings were commenced by the announce-
ment of the decease of Prof. Arthur Cayley, coriespondent of the
Astronomy Section (rom 1S63. M. Hermiie then gave a short
.tccoun: of the scientific work of the grea' mathematician. — -On
argon, a new constituent of the atmosphere, discovered by Lord
Ivayleigh and Prof. Ramsay. An abstract by .M. Berthelol of
niattei that has abeady appeared in these columns. He concludes
with the observation that, although argon has no action on the
higher animaKs, it cannot be predicted that bacteria may not be
affected by it, for it is known that thry absorb nitrogen. The
suggestion is made that nitrogen obtained from the total
destruction of animal or vege'able matter should be examined
for argon. — On abelian functions, by M. H. Poincarc. — Pro-
pellers with tangential penetration, by M. Guyou. A descrip-
tion of .1 mo<iel of a new type of propeller. — The present state
of investigations on the vegetation of French colonies and pro-
tectorates, by M. Ed. Bureau. — On a passage of the shadow of
lupiter's fourth satellite, by M. J. J. Landerer. The calculated
time of half-pa'sage is 27m. 9s. ; observation gives the time as
2lm. 30s. — Solar observations made at Lynns O iservatory
during the fourth quarter of 1894, by M. L Guillaume. There
appeals to have been a general decrease of spots and facula;
since the llrst quarter of 1893. — On continuous straight
beams rigidly connected with their supports, by M. Eugene
Lave. — On the nature of the " displacement current " of Max-
well, by M. Vaschy. A mathematical paper in which the au hor
showsthat certain propenies admitted by Maxwell as hypotheses
are mathematically exact, and may he deduced from his theory. —
On the anomalous rotatory dispersion of crystallised absorlient
media, by M. G. Moreau. — On Fresnel's biprism, by M.
< ieorges Meslin. — -Influence of low temperatures on the attrac-
tive power of a'tilicial permanent magnc's, by M. Raoul
Piciet. The tabulated mean results of lour sets of experiments,
agreeing well together, sh w a continuously increasing attrac-
tive power as the temperature becomes lower. The range of
lempera'ure in these experiments was from -; 30 to 105'. —
Moniodamra' nium d'rivalives of hexamelhyltrianidoiiiphenyl-
roethane, by M. A. Roscnstiehl. Meihyl iodide forms with
the cnmi'lex triamines AjfC.R (where A represents
(CHjjj.N.CcHj, and R indicates an electropositive radical
such as H, Oil, or OCM3) two series of colourless combina-
tions. (1) The first contains one atom of pentavalent nitrogen.
Compounds of this class exchange the radical R for an acid
radical, and form colouring matters. (2) The second series,
formed by the addition of three molecules of methyl iodide,
contains three pentavalenl nitrogen atoms. Colouring matters
arc not formed in this case, as the radical R cannot be ex-
changed for an acid radical. — On laccase ant the oxidising
power of this diastase, by M. G. Berirand. — Reactions of
chelidonine with the phenols in sulphuric solution, by M.
Batlandier. Wiih a drop of guaiacul dissolved in o 5c.c. of
concer traled sulphuric acid, chelidiinine moi3tened and exposed
to the air gives a fine carmine colourali>n. A list of colour
reactions with other phenols is given. — On the development of
the liwly in the shrimp {Palcmon serralii, Fa'ir.) and the cray-
fish [A'tiuui fluvialilis, Gesn.), iiy M. Louis Route — On the
production ol females and ma'es among the Mel pnnas, by
.M.J P« rez. — -On the iiiflur nee of climaiological conditions on
the gr iwlh of tree«, l>y ^L Kmilc Mer. Ttie author shows
that ihe diynen of 1893 caused a diminution in tfie growth of
wood in lore*l tree*. A similar effect was producel by the
excessive r:iinfall of 1888 — On refi action in polychroic aureoles,
by M A Michel Levy. Wh- n Ihe aureoles ar- well developed,
with free contours, deeply coloured, the refraction of the pig-
mented part is clearly Miprrior to that of the unm idified sulj-
slance. The difT--rence b twcen the si nilar indicesof rcfr.iction
may amount !■) a decimal of the second ord--r. It 'ollows that
ihc cor<st'tutt«in of the mineral is profounrlly modified, as its
ellip«oid ol optical elasticitv is different. — On Ihe existencr of
numerous remains of sjroniics in Ihe phtaniiti of the Prc-
caml'rian of liriilany, by M. L. Caycux. Conclusions: (1)
There exist, at the base of the I'recambiian of Brittany,

NO. 1320, VOL. 51]

numerous and varied sponge spicules. (2) Almost all, if not
all, the orders of .sponges with siliceous skeletons are repre-
sented at this earlv epoch. — On the exi>lence of a submarine
delta in the Upper Cretaceous near Ch;itillon-en-Diois, by MM.
G. Sayn and P. Lory.

BOOKS, PAMPHLETS, and SERIALS RECEIVED.

KoOKS. — The Fniindalioiifi of Belief: A. J Balfour (Loncmans). — Cellu-
lose : Cross and Bcvan (Longiiianv). — Thoui^hts on Kclij;ion Dr. G. J.
Romanes (Longmans). — Elctrentary Lesson% in fc.lcctriciiy .-»t>d Maenctism:
Prof. S. V. Toompson. new ediiion ( Macmittan). — Remaikiible Comets:
W. 1". Lynn, 3rd edition (Stanlcro) — Varied Occupations in W caving : L.
Walker ( VlacmtUan) — I hcoretical Lliemistrv fr-»in the Staiidpoini of Avo-
gadro's Kulc and i hermodynamics : Prof. \V. Ncrn-^i, translated by Prof.
C. S. Pilmcr (Macmillan) —Atlas of Classical Antiquities : Th. Schrciber,
edited for Lngbsh Use by Prof. W. C F. Anoerson (Maimillun) — Annuaire
de L'Obscrvatoire Koyale de Be'gique. 1S95 : F. F -lie (Bru-veHes, Hayez).
— Alembic Club Reprints ; No. 10, Researches on the .■Vrseniates. Phos-
phates, and Modifications of Phosphoric Acid : *!'. Graham (Edinburgh,
Ctay). — Die Hearbeitung des Glascs auf dem Bl.iseiischc : D. Djakonow
ai'd W. Lennanioff (Berlin. Friedi;inder). — A Treatise on Industrial Photo-
metry with Special Appl)C»ti<m to Electric Lighting : Ur- A. Pa'.-i/. trans-
lated hyG. W. and i\L R Patterson (Lnw).— Bulktin of the U.S. Fish
Commission. Vol. xii. (Washington).— Chem cal LahO'atory Labels. Parts:
W, H. Sym-ins (viallenkactnp). — Bra'^ilische Pil/biunirn A. Moller(JeDa.
Fischei)— Elliott Brothers' Catalogue : No.| E4 (Elliott). — A Fisherman'-.
Fancies F. B. Ot-veton (Stock). — Calendar of the Ueparimcni of Science
and An, 1895 (C>re and Spo'tiswoode).

Pami'IIlets. On the Present Relations of Agriru'tural Art and Natural
Science: Prof R. Wanngton (Frowdc).— Uibliography of Accio Acetic
Ester and its Derivations: P. H. Seymour (Wa hingtoni. — Geology of the
li tston Basin. W. O. Cr »sby. Vol. i, Part r (Bosi.n). — N'orih American
Bows. Arrows, and Quivers : O. T. Mason (Washington).— (^uelques
Apcrtjus sur rtsthciique des Formes: C. Heorj" (^'af'*. Nimy).

SEKiAL-i.— Quarterly Journal of ihe Geological b' cit-tv Vol. li. Parti.
No. 201 (i* mgman^). — IVansaciions of the English Arboriculiural Society,
Vol. 3, Part 4 (Carli>Ie).— Psycholoiiischc Arbciten, Er-^tcr Band, i Heft
(t eipzig. Engelmann). — American Journal of Maihcmatics, Vol xvii. No. i
(Balti xorej —Bulletin of the American Maihemati>al Socieiv. Januar>-
(Ncw York, Macmillan). — Bulletin de la SocicnJ ImpL-r.ale des Natiiraliste>
de M iscou, i3j4, No. 3 (.\Iosc ■uK — Pr cecdii-gs ol the Physical Sociei\
of L'lndon. Vol. .xiii. Part 3 (Taylor and Francis) —Procedings of the
Academ\ of Nacural Sciences of i'niladelphia, 1894, P-»rt zfPh.ladclphia).
— Bulleiin of the BnfTato Society ol Natural ^cl^nces. Vol. v. No. 4
(BufTalo). — Bulletin de L'Acadc iiie Impcuale dcs Sciences de St. Peters-
bourg, January (St Pctersb..urg). — U.S. Dcparimcnt ol Agricultun-
(Divoion of Chemistry), Bulletins Nos. 41-43 (Wa<hingi m) — Proceedings
of the Boston S <ci-ty of Natural History, Vol. xxvi Paris 2 and ,^
(Bosiun).— American Journ.ilo) Science, Fcbruarv(Ncw Haven). — Medical
Magazine, February (Strand). — Journal ot the Acad«-iuy of Natural
Sciences of Philadrlphia. jnd .serie«, V'>l. x. Part 2 (Philxdelphta). — Strand
Magazine, February (Newncs)— Strand Musical Maga7ine, February
(Newncs). — Pi. lure Magazine, February (NewnrsL— Science Progress,
February (Scientific Press, Lid.). — Bulletin of the G-ological Institution
of the University of Upsala, Vol. t, Nis. 1 and a (Upsala).

CONTENTS. PAGE

Electric Oscillations. ISy Prof. A. Gray 361

The Book of the Rose. l!v W 362

Our Book Shelf:—

Warner: " L'Induslrie des Araneina." (Illustrated).

R. I. P 363

Hewitt : " Elementary Practical Chemistry, Inorganic

and Organic" ■ 364

Murray: " 1 1 iw ti Live in Tropical Africa" .... 364
Letters to the Editor: —

The Liipicfaction of (iisc — M. M. Pattison

Muir; Prof. James Dewar, F. R S 364

Vertehrate Sc(;mentaii>/n. — P. Chalmers Mitchell . 367
The lilack-veiiied White Butterfly.— W. Warde

Fowler . . .... ... . 367

Parr.its in the Thilippine Islands. — Prof. Alfred

Newton, F. R.S. ... 367

Twenty- five Years of Geological Progress in Britain,

Iiy Sir Archibald Geikie, F. R.S 367

Notes 370

Our Astronomical Column : —

The Masiof the Asteroids 373

The Apparent Uametcri of Mercury 373

The V.ir ation of Latitude 373

Th-- Sun's Place in Nature. I. (lUuslralei!.) By J.

Noiman L^ckyer, C.B., F.R.S 374

The Itisntution ol Mechanical Engineers 377

The Advance of Technical Education. By R. A.

Gregory 379

Sc ence in the Magazines 380

University and Educational Intelligence 383

S icioiieh 4nd >c ••loroies 3S3

Books, Pampniets, and Serials Received .... 384

i

\NA TURE

J85

THURSDAY, FEBRUARY 21, 1895.

SIR ANDREW CROMBIE RAMSAY.
Memoir of Sir Andrew Crombie Ramsay. By Sir
Archibald Geilcie. (London : Macmillan and Co.,
1895.)

THE memoir of Sir Andrew Crombie Ramsay, by
Sir Archibald Geikie, is a valuable addition to
literature and to science. We will refer our readers to
the book itself to learn when Sir Andrew was born and
when he died : what support the theories of heredity
obtain from the scientific tendencies and noble courage
of his parents and fore-elders : who were the teachers and
friends, and what were the surroundings of his early
years : what, in fact, made Ramsay such as we find him
in later life — a prominent person in whatever circum-
stances he was thrown, whether in the small society of a
provincial town or in scientific gatherings in London — a
welcome guest at every table, a critic whom any author
bolstering up wild theories with bad evidence would fear
to have to reckon with. "Of an eminently social
temperament, he made acquaintances easily wherever
he went, and these chance acquaintanceships sometimes
ripened into lifelong friendships. In one family circle
we find him reading aloud Shakespeare, or Scottish |
ballads, or a good novel ; in another, he takes part,
heart and soul, in singing glees and madrigals ; in a
third, he joins in dancing and all kinds of merriment."
" English literature was to him avast and exhaustless
garden, full of alleys green and sunny arbours, where
from boyhood he had been wont to spend many a
delightful hour. When he found among his colleagues
one whose talk was not always of stones, but who had
ranged like himself far and wide in literary fields, he
opened out his inner soul, and his conversation glowed
with an animation and power, as well as a gleeful e.\-
uberance, which astonished and charmed his companion."
And "though he was not in any sense an antiquary, he
knew a good deal about the history of architecture, and
took a keen delight in visiting ruins and trying to form a
mental picture of what they must have been before the
gnawing tooth of time had dismantled them. Whatever,
indeed, linked him with the past had a charm for him.
He never willingly missed an opportunity of seeing a
ruined castle or keep, a mouldering abbey, a grass-grown
encampment, or a lonely cairn. If tradition or song
invested any spot with a living interest, he would not
consider his geological inspection complete if it had not
included a visit to that site." With his quick sympathy
and conversational powers, with his wide knowledge of
nature, as well as of history and her monuments, no
wonder that he was welcome in any society of intelli-
gence and culture. He would unbend in congenial and
sympathetic company, like a strong man who had been
out ill the cold and had at last gained a warm fireside
but he always made room for others round the fire. His
impulsive and generous nature was, however, tempered
with native judgment and caution. He soon gauged the
character of those with whom he was thrown, and
quickly estimated the amount of receptivity and the
temper of an audience.

NO. <32I, VOL 51]

These qualities and acquirements with a strong and
clear memory gave him much wealth of illustration in
scientific discussion and in lectures. But his power lay
more in the lucid exposition of his subject, the keen
insight into the real points at issue, and the clearness
with which he brought forward his array of facts and
arguments. After one of his lectures at the Royal
Institution, Faraday ran up to him, shook him by both
hands, and asked "where did you learn to lecture?"

In the memoir will be found an account of his appoint-
ment to the chair of Geology at University College, from
which he was always spoken of as Prof. Ramsay ; also
of his lectures there and elsewhere, and of his various
other literary work.

In 1841 he was appointed Assistant Geologist on the
Government Survey, under Sir Henry De la Beche, and
throughout his forty years of service he was more and
more identified with all its active work, either as himself
taking part in the mapping, or as superintending others,
though it was not until he had been appointed Director-
General, in succession to Sir Roderick Murchison, that
he officially represented the Survey to the public and the
Government. An account of his life is therefore the
history of the -Survey, and no one is more competent than
our author to tell the story.

The great difference between the work which has to
be done by the Geological Survey and by amateurs is this.
The amateur may examine a district in more or less
detail, may pick out the points of interest, or the facts
which illustrate some theory which he is developing, but,
where he sees nothing, he may say nothing about it. The
Geological Surveyor, on the other hand, must colour all
his map, and sometimes has to put in by inference whole
formations of which he has seen nothing whatever.

" He spends the day, map in hand, over the ground
assigned to him for survey. Every exposure of rock is
noted by him on his map or in his note-hook, with all the
needful details. Each stream is followed step by step up
to its source ; each hill-side and ravine is traversed from
end to end ; each quarry, sometimes each ditch, and
even the very furrows and turned-up soil of a ploughed
field are scrutinised in turn. . . . He is brought into
every variety of scenery, and is compelled by his very
duties to study these varieties and make use of them in
his daily work."

But even after all this careful search it often happens
that he can find no direct evidence of the solid rocks
below the soil and subsoils. He has to plot sections and
see what, with the known thicknesses and dips, should
be found there. He has to examine the surrounding
country to sec what occurs in the same relative position
elsewhere, and whether any lines of disturbance which
might complicate the results are running into the area
respecting which, with little evidence, he must make up
his mind and say something. The survey work is thus a
grand training in the faculty of keeping one's wits about
one, and of detecting sources of error. The habit of
mind thus formed is often exhibited in the criticism of
amateur work by trained survey men, and many can re-
call Ramsay's indignant protests against impossible or
exaggerated sections when appealed to as evidence in
support of any view.

He had a wonderful " eye for a country," to use one of

S

;86

NA TURE

[February 21, 1895

his own favourite expressions. He rapidly took in the
lie and relation to one another of the rock masses. To
this any geologist who has worked with him in the field
can testify, and this is what lends its value to his classical
memoir on the geology of North Wales, and to the
maps and sections of which it is explanatory. But when
he had sketched out the outlines of the history of the
ancient volcanoes of that area, and had noted the choked
craters now exposed by the denudation of the overlying
masses of lava and cinder and mud, and when he had
described the isolated portions of the volcanic and marine
deposits which, building up mountains round the ancient
roots of the volcano, still remained the record of great
sheets that once spread continuously far and wide over
the whole area ; when he had done all this, he turned
to another aspect of the question, and sought a clear
answer to the inquiry how much rock, which we know
surely once covered this area, has been removed by
denudation .' and we find in the same memoir sections
illustrating the conclusions at which he had arrived.

For when " he had traced out the structure of a com-
plicated geological region, and was able to show what
should have been the form of the surface had it depended
on geological structure," he was then ''in a position to
demonstra'e how much material had been removed by
denudation," namely, all that was above what he called
the Plain of Marine Denudation, that is the old base
level of ancient erosion, down to which all the agents of
waste — rain, rivers, ice, and sea — had reduced the up-
lifted land ; or perhaps, as we should now say, giving
greater prominence to subacrial action, to the level at
which the sea had arrested the work of the various
agents that were reducing all dry lands to sea level..

Few men's work illustrates better than Ramsay's the
place and value of a good " working hypothesis " in some
kinds of higher scientific research. Imaginative and
fertile in suggestion, no one was more sorry when
further observations did not clearly support his first
impressions, and he tried and tried and tried again to
make it fit ; yet he bowed always with deference to
established evidence and logical consequence.

Besides his regular survey work, which was itself full
of new observations and original treatment, and besides
many papers giving the results of his researches on
special points, he from time to time plunged into more
speculative questions, and advanced some theory in
explanation of the larger phenomena, especially those
connected with surface configuration. For instance,
reflecting on the great quantity of fine mud, " flour of
rock," carried down by glaciers, and observing that ice
was not, like water, restricted in its flow to continuous
downward slopes, and holding that ice charged with
stones would grind away more rock where the pressure
was greater or the rock softer, he propounded the theory
of the glacial erosion of rock basms.

Ills explanation is probably true in some cases, but he
gave it a wider application than has been borne out by
subsequent investigations.

Unfortunately he adduced as his first example the
Lake of Geneva, a basin to which even those who agree
with him upon the general probability of there being
glacially eroded hollows such as his theory requires,
would not now be prepared to apply it.
NO. I 32 I, VOL. 51]

The public will read with profit and pleasure the
biography of such a striking personality by a graceful
and accomplished writer, who knew all about the man
and his work, and had the skill to select with judgment
and the good sense to keep the whole within the modest
bounds of one volume of large print. Ramsay's many
friends will love to have the record of his struggles and
his triumphs, so many of which are told in his own words.
Every survey man, not only of Great Britain, but through-
out the world, will turn to this account of the commence-
ment and growth of the geological survey of Great
Britain, and cannot fail to profit by the insight it gives
into the methods, life, difficulties, and results of that
important branch of the public service.

So easily does the story run, that we cannot say
whether the general reader, or the scientific student, will
be-t appreciate this sketch of the progress of geological
research through the most active and interesting half-
century of its history.

OUR BOOK SHELF.

Harvard College by an Oxonian. By George Birkbeck
Hill, D.C.L. (London : Macmillan and Co., 1S94.)

Dr. BiRKliECK Hill spent two months in 1893 in
Cambridge, Massachusetts, and has compiled this little
volume giving some account of the history of the cele-
brated college and university of Harvard. So far as
Dr. Hill rclie> upon previous publications, his account is
accurate, but his own observations and impressions are
— as is very natural — ofien quite erroneous. Scant
justice is done to the import.Tnt and costly arrangements
for the study of the various branches of the natural
sciences which exist either at or in connection with the
Massachusetts university. Dr. Hill is not fitted by his
own education and experience to report on these matters,
nor, indeed, can much value be attached to his some-
what antiquated standpoint as a critic or observer
of university institutions. He contrasts Oxford and
Harvard at every step, but he fails to give any picture or
presentation of the real characteristics of the student's
life at Harvard. He does not sufficiently emphasise the
fact that the undergraduate at Harvard enjoys the im-
mense benefit of true university education, at the hands
of distinguished professors, with freedom and inde-
pendence in regard to his choice and meihod of study,
and as to such personal details of life as board and
lodging ; whereas the Oxford undergraduate is treated
throughout his career as a goose to be nursed, monopo-
li^ed and plucked by college ushers, who (owing to the
system under which they are appointed) arc, as a rule, as
little capable of good teaching as they are of managing
the domestic and disciplinary details of the college-
boarding-houses. Dr. Hill notes that the rage for
athletics is almost as serious an injury to study at
Harvard as it is at Oxford. L.

Tableau MtHrique dc Logarithmes. By C. Dumesnil.

rParis : Libralric Hachette and Co., 1S94.)
The use of logarithms for calculations is, as every one
knows, a great saving of labour and time, and what
otherwise would be complicated pieces of work are re-
duced to simple computations. The facility of woiking
depends, alter some time, on the good or bad arrange-
ment of the tables, but instances often occur where
much time is lost by having to turn pages backward
and forward. For the case of logarithms to five places
of decimals, M. Dumesnil has devised a means of
eliminating altogether the use of tables, by adopting a
series of scales neatly printed on stout sheets. From

February 21, 1S95]

NATURE

387

ihese scales the divisions are so arranged that all the
logarithms of the numbers from i to 10,000 can be easily
read off, and vice versa. The scales, or tables as they
arc called, are published in two qualities. The cheaper
are neatly and clearly printed, and on a smaller
i scale than the other ; but, on the whole, we recommend
I the more expensive sheets, as the numbering is more
<;asy to follow (coloured numbers being used), and the
di\ isions are more legible on them.

To understand the method of working the tables is a
matter of only a few minutes' attention, and when
grasped, either the logarithm of a given number, or the
number from a given logarithm, can be read off without
the least hesitation. The book of instruc-
tions, which IS separate from the tables,
contains all that the user of the tables
can require. The explanations are full
,->.nd concise, and the worked-out examples
will prove an excellent help in acquiring
the methods of solution.

Jn the Guiana Forest. Studies of Nature
:i! Relation to the Strugi;le for Life.
15y Jaine> Rodway, F.L.b With an In-
troduction by Grant Allen. Illustrated.
(London : T. Fisher Unwin, 1894.)

\\ K have read Mr. Rodway's book with
.1 good deal of pleasure. Such a subject
as the struggle for existence amongst the
animals and plants of the Tropics, could
not fail to be full of interest when dealt
with by an enthusiastic lover of nature.
For it is in the Tropics that nature's
principal workshops are situated, ai.d no
naturalist can afford, nowadays, to
neglect that essential element in a liberal
biological education — a visit to these
regions. There the struggle for life is
no longer, as in our .own climates, a cold-
blooded process which only a trained
eye can follow, but a fiercely active
competition for the means of subsistence
which is everywhere apparent in every
detail of the structure of the individual
and of the economy of the species. The
"heartless vegetable" amid such sur-
roundings seems no longer a reality, but
the cold figment of a northern imagi-
nation.

Mr. Rodway describes the vegetation
of the forest, the swamp, the sand-reef,
and the sea-shore, and each is sketched
in vigorous outline. One cannot, how-
ever, avoid wishing that the author had
been contented to give his impressions of
the actual facts, without indulging in
metaphysical moralising which is not
scieniific, and is not always common
sense. Occasionally, too, he gives way
to great prolixity, as, for instance, in an
«xcursus on the interdependence of
animals and plants, which is all very like something we
have heard before, only that Mr. Rodway's siory is
longer. The author is on dangerous gr lUiid when he
ventures to dip inti the philoso(jhy of natural selection,
or to deal with problems of variation.

But notwithstanding these defects, the book is worth
reading. It is well illustrated, and contains a large
amount of really interesting observation which may
Stimulate the general reader, and which will recall many
a half forgotten scene to those who have them elves
been travellers. The accompanying illustration, for
which we are indebted to the publisher, shows a silk
cotton-tree crowded with epiph)tes.

NO. I 32 I, VOT.. 51]

Lehrbtich der Experimentalphysik. Von A. Wiillner.

Band i. 5te Aufl. (Leipzig : Teubner, 1895.)
Students who wonder when we are to have an
English treatise on experimental physics worthy of com-
parison with this well known German one (and the
French textbooks of Jamin and Violle), will find food
for reflection in the fact that thirteen years have elapsed
since the last edition of Wiillner (the fourth) was pub-
lished. Much the same thing holds good of other
German scientific treatises, notwithstanding that pub-
lishing firms of repute in the Fatherland do not consider
it beneath their dignity to quicken the sale of the rem-
nant of an edition by having notices posted up in the

^^

Universities intimating that bond fide students of the
subject can secure copies at a reduced price by applica-
tion through the University Professor.

In the present case the interval has been well em-
ployed. The first volume has grown to 1000 pages — or
150 more than in the fourth edition— and ihe most
important researches published up to the end of 1892
have been incorporated. In the last edition the article
on internal friciion contained simply a discussion of
torsional vibrations and logarithmic decrement, followed
bya page in which mention was made of the researches of
Schmidt and other-, with a statement of the conclusion
arrived at, viz. that in such elastic oscillations the

i88

NA TURE

[Februarv 21, 1895

motion is opposed by an internal resistance or friction
which is measured by the logarithmic decrement and is
distinct from the elastic after-etTect. In the new edition
six pages are devoted to Boltzmanns theory of internal
friction of solid bodies, according to which the damping
of oscillations is regarded as due to the elastic after-
etTect, the result of which is that the force urging the wire
towards its position of equilibrium is not proportional to
the displacement. In the fourth edition there was little,
about " Hardness," beyond a list of the substances form-
ing Moh's scale ; indeed, the whole article on the different
kinds of /Vj//>/t«/ was rather unsatisfactory. Now the
researches of Hertz and the experiments of .Xuerbach
have made it possible to measure the hardness of a sub-
stance absolutely and without reference to the properties
of any other substance.

Instead of being relegated to the volume on heat, as in
some text-books, the kinetic theory of gases is here de-
scribed at considerable length in the section treating of
the properties of gases. This section has been over-
hauled, and Stefan's theory of gaseous diffusion is given
in place of O. E. Meyer's. Prof. Wiillner attaches so
much importance to recent developments of the electro-
magnetic theory of light, that he has determined to alter
the sequence of the subjects in his treatise, so that light
and radiation may come at the end. In the edition now
appcanng, the second volume will therefore treat of heat,
and the third of electricity. pi:

Peru. Beohachtttngen unci Studicn iibcr das Land iind

seine Bcwolmcr wdltrcnd eincs lyjulirigen Atifcnllialls.

Von E. W. Middendorf. (Berlin : Robert Oppenheim,

1893-94.)
Dr. Middendorf commences his treatise on Peru by
a long preface detailing the circumstances which led him
to choose that country for his home. Starting as the
surgeon of an Australian emigrant ship from Hamburg
in 1854, he narrates the incidents of the voyage, an
epidemic of cholera and other irrelevant accidents in-
cluded, until on the return journey, sick of the sea, he
left his vessel in Valparaiso, and after some further
wandering took up his residence in Peru, and was led by
degrees to pay closer and closer attention to the land and
people of his choice.

The work is planned in three parts. The first volume
deals nominally with Lima, the capital ol the republic,
but is really much wider in its scope, commencing with
the history of Peru, and after describing the town with
its streets and public buildings in somewhat tedious
detail, proceeding to discuss the genera linstitutions of
the country from the standpoint of the capital. People,
church, government, law, education, commerce, transport,
and charities arc all discussed ; and at the end two
chapters describe the municipal markets, slaughter-
houses, water-works, bull-fighting arenas, theatres, and
other places of amusement. The second volume de-
scribes the coast lands of Peru northward and southward
of the capital, the towns and seaports, the provinces
now ceded to Chile, the railway communications, and
the antiquities. A third volume is promised dealing
with the highlands, but presumably the scheme does
not include an account of trans-Andine Peru.

\Vc cannot look on Dr. Middcndorf's work as an
exhaustive or even a comprehensive work on Peru. It
IS indeed a book lor the general reader rather than the
student. Abounding as it does in personal reminiscences,
and written in an easy conversational style, it should do
much to further the knowledge of the country it describes
amongst (jcrman-speaking people. IJut it is, we fear,
too diffuse and bulky to serve tins purpose with the same
degree of satisfaction that a smaller work might have
secured, and it lacks firm and wide generalisations
which could present a clear picture of the land and people
as a whole.

NO. I 32 I, VOL. 51]

LETTERS TO THE EDITOR.

\Thc Editor does not hold himself responsible for opinions t.\
pressed by his correspondents. Niither can he undertak.
to return, or to correspond -.vith the writers of, reieclc.
manuscripts intended for this or any other part of NATURE.
No notice is taken of anonymous communications.}

The Liquefaction of Gases.

A CAREKUL Study of his letter in Natuki; of February 14
shows that Prof. Dew.ir makes four c'.iim'!.

(i) He claims that in his lecture in 1SS4 he employed an ap
paralus "more readily and quickly handled" than that of
Messrs. Wroblewski and Olszewski, in the illustrations he gave
of the work of these investigators.

(2) He claims that in tiis lecture in 1S84 he used liquii.
nitrous oxide for ihe production of liquid oxygen.

(3) He claims that in 1SS6 he li'iuefitd oxygen by passir,
the gas through a long copper coil surrounded by liquid eihylent
and that his apparatus made it possible to transfer the liquii:
oxygen to a glass vessel wherein it could be used as a cooling
agent.

(4) He claims that, in conjunction with Prof. Liveing, h;.
deterojined the refractive index of lii|uid oxygen before the pub-
lication of Prof. Olszewski's first paper on the subject.

I shall consider these claims in order.

(1) The apparatus used by Messrs. Wroblewski and Olszewski
in 1SS3 is fully described and figured in H'iedemanii'
Aiinalcn for that year (xx., 243). The gas to be liquefied wa-
strongly compressed in a glass tube, imbedded in an iron
cylinder, and connected by a capillary tube with a glass vessel,
which in turn was connected with a slore of liquid elhyleoe,
previously cooled by passing through a narrow copper lube twr
metres long immersed in a bath of solid carbon dioxide ; tlu
glass vessel was also connected with a double oscillating I'ianchi
air-pump. The liquefied gas was collected in the glass vessel,
and its properties were examined. A comparison of the appa
ratus of ihe Polish Professors with the brief de.scripiiiin in tlu
Proceedings of Ihe Royal Institution of the apparaius used by
Prof. Dewar in 1S84 "for the purpose of lecture demonstra-
tion" will, I think, show that I slated the mailer fairly in my
former leiter by siying that Prof. Dewar "describes and figures
an apparaius which is a slightly modified form of that of thfr
Polish Professors, which in turn was derived from the
apparatus of Caillelel."

(2) If anything was gained by using liquid nitrous oxide for
Ihe liquefaction of oxygen, why has not Piof. Dewar continuei'.
to use this refrigerator?

Prof. Dewar claims to have devised a inetho 1 f 'r liquefying
oxygen which was so much inferior to that brought into prac-
tice by Wroblewski and Olszewski that it was abandoned almost
as soon as it was devised. I suppose his claim may be admittc '
here.

(3) Granting that the substilulion of a long copper coil for
strong glass luhe was an improvement, it must not be forgotlci
ihat the apparaius of .Messrs. Wroblewski and Olszewski, de
scribed in 18S3, enabled the liquefied gas to be collected in
vessel wherein its properties not only might be, but were,
studied. That this apparaius was an efricirnt insuumen; i-
shown by the facts that before ihe year(iS86) in which thi
copper coil method was described, Profs. Wroblewski an.
Olszewski had liquefied oxygen, nitrogen, and carbon monoxide
Prof. Olszewski had liquefied air, nitric oxide, and marsh gas ;
h.ad determined the boiling poinis, at atmospheric picssurc, and
the criiical temperatures and pressure?, of these .six gases ; ha>',
solidified nitrogen, chlorine, hydrogen chloride, nilric oxide
carbon monoxide, and marsh gas ; and h.ad made careful deter
minalions of ihe behaviour of hydrogen at - 211 and - Jjo .
Hut with his copper coil 45 feet long Prof. Dewar did nothing
for, so far as can be judged fiom his published papers, he Av'
not initialc experimenis on the properties of liquefied oxygen,
nitrogen, or ai', until 1S91 92. I think we may conclude tb.i'
Ihe apparaius of Ihe Polish Professors was beiui adapted foi
accuralc wink thr'n "that made wholly of mclal " t"
which Prof Dewar refers. If Prof Ilewar's apparaius oi
1SS6 was "safer and better" ihan " ihat used in Cracow in
i8yo"— as he says it was— why was not this safer and heller
apparatus lurn<d to some scienlihc use before a descriplior.
appeared of ihe apparatus of Prof. Olszewski, in which the
gases were liquefied in a steel cylinder and then transferred l>

February 21, 1895]

NA TURE

389

a glass vessel ? In his letter of February 14, Prof. Dewar
tells us that by mean'; of the copper coil apparatus of 1886
"liquid oxygen was made and decanted or transferred from
the vessel in which it was liquefied to another by means of a
valve, and thereby rendered capable of use as a cooling agent."
Why, then, did he not use the liquid oxygen as a cooling
agent? It is strange that seven years after this, when Prof.
Dewar wished to " prosecute research at temperatures
approaching the zero of absolute temperature," he says he had
" no recorded experience to guide [him] in conducting such
investigations." Had he forgotten his own apparatus with its
copper coil 45 feet long ?

Prof. Dewar's apparatus of 1886 must have been peculiar ; in
one sentence in his letter of .February 14, its deviser speaks of
it as "entirely different in type from the crude plan Olszewski
adopted in iSgo," and in another sentence he assures us it was
"practically identical in principle with that used in Cracow in
1890."

The apparatus of 1886 succeeded, in Prof. Dewar's hands, in
producing solid oxygen ; why have we heard nothing of that
solid oxygen? Determinations of some of the constants of that
substance would be interesting and important.

I must beg attention to an instance of Prof. Dewar's bold-
ness. In 1SS3 Mes-rs. Wroblewski and Olszewski liquefied
oxygen, and other gase>, in a strong glass tube ; in 1SS4 Prof.
Dewar repeated some of the experiments of the Polish Pro-
fessors, using, as they had done, a strong glass tube, but
adapting some parts of their apparatus so as to make it " for
the purpose of lecture demonstration . . . more readily and
quickly handled"; in 1890 Prof. Olszewski described an
improved and enlarged inHrument, based on that described by
-his colleague and himself in 1SS3, wherein the liquefaction was
effected in a steel cylinder. Vet, in his letter to Nature of
February 14, Prof. Dewar says " replace the glass tube in «/f
apparatus of 18S4 by a small steel cylinder, and attach to its
lower end a narrow copper tube with a stopcock, and
the Olszewski apparatus of 1S90 is produced." (The italics are
mine.)

(4) As regards Prof. Dewar's joint claim to priority in the
determination of the refractive index of liquid oxygen, I admit
he is tight and I was wrong. I was misled by the date at the
beginning of the paper which contains the earliest measure-
ments by Messrs. Olszewski an 1 Witkowski of the refractive
index of liquid oxygen. The paper is headed Extrail tin
BulUlin de I' AcaJhnic lies Sciences de Cracovie, Octohre 1 89 1.
At the end of the paper is the date 15 Juillet 1S92 ; this, and
the footnote, quoted by Prof. Dewar, make it evident that 1891
at the beginning of the paper is a printer's error for 1892. I
am sorry I made this mistake. Nevertheless, consilering that
Olszewski's quantitative experimenis on the optical properties
of liquid oxygen were bjgun in 1887 ( IVicd. Ann. xxxiii., 570),
and were continued in January 1891 (ibid, xlii., 633), I hold I
was justified in referring to Prjf. Dewar's experiments on the
optical properties of liquid oxygen as " mainly repetitions of
the work of Olszewski and Witkowski."

Tow.ards the end of his letter Prof. Dewar refers to a quota-
tion I made from one of his lectures {" Having no recorded
■experience to guide us . . . ") ; he follows mv quotation (of
which he gives only a part) by another to the effect that " the
necessity of devising some new kind of vessel for storing and
manipulating exceedingly volatile fluids, like liquid oxygen and
liquid air, became apparent when the optical properties of the
bodies came under examination. " I had expressed admiraton
"of the skill which produced" Prof. Dewar's new vacuum
receivers. Prof. Dewar now tells us that when he prefaced
his account of the making of these receivers by the sweeping
assertion that he had no experience to guide him in conducting
investigations at very low temperatures, he did not mean what
he said ; it was merely his way of saying that the vacuum
receivers he was about to describe had not been made before.
It was not I who made, it was Prof. Dewar himself who has
made, a "glaring misrepresentation of the meaning" of his
own words.

Prof. Dewar lays no stress, in his letter, on his own experi-
ments on chemical action, phosphorescence, &c., at very low
temperatures. It is these experiments, I suppose, that are
referred to when he speaks of "thro*ing his bread upon the
waters " ; or does he abandon them as trifling, in that strange
sentence — " Have I ever suggested that Prof. Olszewski was
anticipated, or attempted to taise any question of priority ? " ?

NO. I ■^2 1, VOL. 51]

Prof Dewar hides the essential questions in a
mist of words. If he has made marked improve-
nienls in the methods of liquefying and manipu-
lating the more permanent g.ases (besides his
invention of vacuum receivers) ; if he has con-
ducted original, accurate, and thorough investi-
gations into the properties of the liquefied gases,
where are the accounts of this work to be found ?
Every student of the subject knows he can lay
his finger on the work of Olszewski, and also on
that of his deceased colleague Wroblewski ; and
he knows that work to be thorough, accurate, and
important. But where can there be found some
distinct account of the scieniific work in con-
nection with the liquefaction of the more per-
manent gases that is attributed to the Fullerian
Professor at the Royal Institution?

I asked, and I siill ask, for an "instant and
serious consideration" of the whole matter
brought forward in these letters by "those who
are truly interested in the advance of science,
and are jealous of the good name of the scientific
men of this country."

M. M. Pattison Muir.

Cambridge, February 17.

Argon.

The beautiful research of Lord Rayleigh and
Prof. Ramsay has proved up to t'ne hilt that in
argon they have discovered an unknown gas
which is remarkable for some of its physical
properties, and especially for its extraordinary
chemical inertness.

Among the interesting questions which have
been raised, but not fully solved, a-e : Is argon
an elementary Viody ? If so, how does it stand
related to the other elements?

There are some who advocate its being an
allotropic form of a previously known element,
just as ozone is allotropic oxygen ; but it has
not yet been produced from, or resolved into,
nitrogen or any other element ; and, until that
should happen, it has the full right to take rank
as a new element.

At first sight the fact of its giving two different
line spectra under different circumstances might
favour the idea of its being resolved into two
bodies; hut the fact that these two very com-
pound line spectra have twenty-six lines in com-
mon, which are not all of them among the
strongest lines, appears to me an argument for
the fundamental unity of the substance.

If argon be an element, what is its place in
Mendele'eff's table? This is at present agitating
the minds of chemists and physicists. The
specific gravity of the gas would lead to an
atomic weight of close upon 20 ; but it is
argued from the velocity of sound through it
that it is a monatomic gas, and therefore close
upon 40. Now, if 20 be the atomic weight, it
will fall in admirably with the periodic law ; if
40, it will be perfectly inconsistent with it. The
argument in favour of 20 is at least five-fold : —

(i) It will fill an existing vacancy in Men-
dele'eff's arrangement ; that at the top of the
eighth column. This is the first "even " series;
and it should be remembered that the later
"even" series in that last column are repre-
sented by the iron, palladium and platinum
groups of metals; the "uneven" series being
as yet unrepresented.

(2) It will follow the periodic law in regard
to its melting point. That should be very low,
like nitrogen, oxygen and fluorine ; and so it is.

(3) It will follow the law in regard to its
atomic volume. That is small ; and so it should
be by analogy.

(4) A great characteristic of argon is its not
forming stable compounds with other bodies, at
any rate at a temperature high above its boiling

c
N

3
0

0

iE

4>

C

0

>

i^

u
CO

0"

■^

0

CO

0.

ih

<

eg

0

z

<

u.

0

z

0

0

m

3}
3]

-1

z

390

NA TURE

[February 21, 1895

point. This properly characterises the other occupants of the
eighth column ; to S'TOC extent in the iron group, and certainly
io the palladium and plitinum groups.

(5) The introduction of a new element with the atomic
weight of 20 (not 21 or 22), will extend the range of certain
recurring numbers which appear ne.ir the beginning of the
series of at.imic wcrigh's. In the existing arrani;emen' of
the atomic weights it will be observed that between oxygen
l6 and fluorine 19 iheie are three units; between fluorine
19 and solium 23 there are four ; then the numbers run I, 3,
1.3, I, 3i. Adding argon at 20 the series becomes symmetrical
all the way fom oxygen to chlorine, as will be seen in the
diagram on the previous page.

If, on the other hand, we were to adopt 40 as the atomic
weight of argon, we should meet with the following serious
difliculiies : —

(1) There is no room for it. To place another figure just
before or just after calcium would disarrange the whole subse-
quent serits.

(2) It would break the periodic law in regard to its meltmg
point.

(3) It would break the law in regard to its atomic volume.

(4) The inactive argon would be associated with metals of
the earths, the compounds of which are remarkably siable.

■5) It W'uld iTing the atomic weight of three elements,
potassium 39, cilcium and argon each ahoul 399. wiihin one
unit. This never occurs elsewhere in Mendelerft"s lahle.

.-Vgainst these consi.ieraiions there i-i the firci'ile argument
deduced from the ratio of the specific heats of argon. I will not
attempt to wei^jh the re-peclive meri's of these lines ot reason-
ing, especial y in the absence of the details of the experiments
on the velocity of sound, and until wc have some kmwled^e of
the compounds of argon. Trustworthy conclusions will not be
possible till this far her information is obtained. It is not a
question of physics versus chemistry, for the true theory of its
place am<>n,> the elements must be able to ciordinate all the
facts upon which both the chemist and the physicist rely.

J. H. Gladstone.

London, February 8.

The Aurora of November 23, 1894.

Per.mit me to c;ill attention to a significant fact disclosed by
a scrutiny of the observations of the aurora of November 23,
1894, and having an important bearing in discussing the auroral
dimensions, and which appears to have escaped notice (see
Nature, January to). I refer to the invisibility of the objects
at Dingwall, to the observers at Tynron, Dumfriesshire.
Extracts from the synchronous accounts in Nature, November
29, p. 107, and January 10, p. 246, will prove this slaleinent.

Tynron, 7.30. — Luminous mist in the northein sky, strong
enough 10 cast shadows on the shining surface of the wet
ground. The mist m.ved from the horiz.m to the zenith, form-
ing a detached luminous belt in patches, disappearing at 8.30,
leaving only the light in the north.

Din^.ratt, 7.30. — .Sky covered in all directions by a canopy
of streamers. At the same lime the arch Hisappc.ired, and
occasional streamers up to eight o'clock. It is not possible
that the arch seen at Dingwall could be the same as the one at
Tynron, because the former had vanished when ihe latter com-
menced to form, whilst there is a total absence of streamers, and
phenomenally brilliant mist not recognised at the other place.
Until mcihiKls of observation and analysis can be introduced that
will eliminate the errors of idenliftcalion, the solution is likely
to be indefinitely postponed. W. H. Wood.

Kirmingham, Fcliruary 3.

Making the necessary allowances for increased apparent
lumino>ilic< of bright streaks, or of layers of light in the atmo-
sphere, by the foreshortening effects of end on, and of edge-
presentations, the observation* at Dingwall and in Dumfries-
shire of the aurora of November 23 last, scarcely seem to recount
very much which wis not at the two places, at least partially, a
fairly comparable anrl nearly conlemporancous description of
the same phenomena. The first-formed light-band of the glow
was very strong at Dingwall from ihc east to west, a litilc
southward from the zenith, until 7.30 p.m., when wilh Ihe
usual drift of such displays lo soui lizards, it became less
prominent theie than the approaching canopy of streamers

NO. I 32 I, VOL. 51]

which supervened, drifting up from the north-eastern sky in rear
o( it. Hut it assumed at ihe same time increasing pri'minency
in Dumfiiesshire (150 miles south of Dingwall), where between
7.30 p.m. and S p.m., it passed overhead in ihe shape of de-
tached patches of light, a form which the belt was also seen lo
as.sume and to break up into, in a slow extinction st.ige at
Slough, in that interval. The display of streamers rising from a
large tract of light-mist approaching Dingwall from the north-
ward and increasing constantly in lustre at 7.30 p.m., did not
extend far south of Dingwall before it faded out soon after-
wards ; and being (as it was seen at .Slough) a dense local dis-
charge of them, its corona of brightly-foreshortened beams over-
head would naturally be a very impressive sight at Dingwall,
although from a positi n 150 miles oistant in Dumfriesshire, the
broad-.iHe aspect of the short outbreak, seen from afar, instead of
from underneath, would only have the appearance of a sheaf of
coloured light projected up from the usual flat streamer-base,
neither very «ide nor extraordinarily lofiy, but of the m.issive
berg-like form, which was its description at Slough, not un-
frequemly noticeable in rather strong auroras ; and it may even
have been quite easily hidden from view entirely at Tynron,
although a clear horizon in the north near Slough allowed its
observation there, by trees or by other obstructions in the
landscape.

If Mr. Wood can happily devise a practical means of per-
fectly recording the times and descriptions of all the rapidly
changing features of an aurora, and the shifting variations of its
misty light-glows, he could no doubt achieve results from ob-
servations which would he no less a bent lit to astronomers and
terrestrial magneticians, than an exact continuous registration
of cloud phenomena would lie of welcome interest to meteoro-
logists and terrestrial clectiicians ; but it needs no great famili-
arity wilh auroral exhibitions to be quite certainly assured that
results of records even so elaborate as those might be, would
never be found to confute, but only to confirm the generally
accepted view of the really cosmical heights and dimensions of
all truly auroral lights and corruscalions ; of all such lights,
that is to say, as show in their spectra the yellowish auroral
line, or some of the other well-recognised spectral indices of
the aurora. A. S. Herschel.

The American Association.

At the Brooklyn meeting of the .\merican Association for
the .-Xdvaiicement of Science last summer, it was decided lo
meet this year at San Francisco, provided reasonable rates of
fare could be secured from the trans-continental routes, as it
was supposed could be done. Prof. Joseph Le Conte for threfr
consecutive years had crossed the coniinent, laden with earnest
and cordial invitations from the Universities and .Scientific
.Societies of California, and the Common Council of San Fran-
cisco, to hold the meeting for 1895 in that city. The short-
sighted policy of the railroads, however, refused to grant any
concessions ; and it has at List been deciiled to meet at Spring-
field, Mass., August 29— September 4. The meetings of
affiliated societies will begin on Monday, August 26 — rather
later than the usual time of meeting.

Springfield is a small city, located in Ihe heart of New
England. It is the scat of the principal arsenal of the United
Slates ; and, while not a University city itself, it is within two
or three hours' ri<le of nearly, or quite, a score of institutions of
learning of the highest grade, including the two oldest and
most powerful Universities in America, Yale and Harvard.
This will be the second meeting at Springfield, the first having
been held in 1859.

The Association is incorporated by the Stale of Massa-
chusetts, and its office and museum are at Salem in that Slate J
but no meeting has been held in New Kngland since ihat at
Bo.sion in 1880, the most brilliant in all the history of the
.Association. The return to New England after this longest
absence, gives unusual interest to the approachirg meeting.

W.\t. H. llALi-;.

Brooklyn, New York, February 2.

I

Earthquake in Norway.

AiioiT midnight on the 4lh and 51I1 of this month, a fairly
strong earthquake occurred in the snutticrn part of Norssay. The
greatest di-tuibance was fell in the environs of the town of
Aalesiind, upon the west coast (about 60" 30' lat. N.). From then

February 2 1, 1895]

NATURE

591

the shocks exiended to the region of the Trondhjems fjord, the
Swedish border, and the Christiania fjoid, and Berg-n, but
the extpcnie fou hwest pait of the country seems to
have been undi-lurbed. The earthquake is also reported
from Fiinen, in Denmark. The movement proceeded in
about seven minutes from the west coa-t to Chiistiama (at
Chrisiian-und iih. 38m. Chiisliania time, iih. 1501. Green-
wich lime) It is inlerfStinu to notice that the earthquake
re=emblcs one which occurred on March 9, 1866, and was
felt across the North Sea at ihe lijjhthouse of Flug^arrock,
on the SheilanI Islands. As I am engaged in collecting daia
aboul the earthquake of this month, I should be glad to know
whether it wosobseived in the British Isles.
Christiani-i, February 11. Haxs Reusch.

"The Black-veined White Butterfly."

My experience of this species in Eng'and enables me to
support Mr. W. Warde Fowler's opinion (Nature, February 14,
p. 367) as to the preference of the spec es for o' en ground. I
met with it in almndance in the New Foic t in 1S66 1868, 1869,
and 1870. It rarely occurred in or near dense woorls, but preierred
the open heaths and wastes of the For st, where thistles were
plentilul. In 1S67 I four d ihespecies swarming, about mid-ura-
mer, in hay fields on 1 ill-sides in Montrou'hi-hnr. Tlieie weie a
few sm ill orchards, but not much wood, in the nei^hbouihond.
For a detailed account olthe ioxmtx A\'i,\\\\t\Avin oi A poria craisgi
in this country, I would refer Mr. Warde Fowler to my ariicle
on the subject in the Entomologists Monthly Magazine for
March 18S7. H. Goss.

Surbiton Hill, March 16.

The Zodiacal Light.

At the present moment— 7 p m. February 16 — the zodiacal
light is more distinct than I ever remember to have seen it in
England. The middle of the base is about 2° to the northward
of the point where the sun set, and the axis is directed towards
the Pleiades, and can be traced as far as the middle of Aries.
I The afternoon has been remarkably clear, and it is now a bril-
I liant starlight evening. J. P. Maclear.

Cranlei^h, Surrey, February 16.

OYSTERS AND TYPHOID.

'pHE statements that have recently appeared, both in
■'■ the gener,il and in the medical press, concerning
the communication of typhoid fever thiough the agency
of oysters when eaten raw, make it desirable to review
some of the data on which the suspicion in question is
based. For many years past it has been a matter
of assumption, when typhoid fever has followed,
within some ten to fifteen days, on the consumption of
raw oysters, and when no obvious cause for the disease
could be detected, that the oysters stood to the fever in
the relation of cause ; and this attitude received no in-
considerable impc us when, a few years ago, a member
of our Royal family sickened of typhoid fever under
circumstances that were suggestive of oysters as the
vehicle of the disease. Then again, it must be admitted
that it has been a matter of no very uncommon ex-
perience amongst medical men to have to treat typhoid
fever in patients who, at an antecedent date correspond-
ing with the incubation period of typhoid fever, had
indulged in an oyster supper after leaving some place of
entertainment. And the suspicion has been confirmed,
in some cases, when it has been ascertained that another
member of the same party, having nothing but the oyster
supper, in common with the sufferer referred to, has also
had typhoid fever about the sune date, or had suffered
from vomiting and other symptoms the day after the
consumption of the oysters. The assumption in cases
of this latter class has been, that the specific poison of
typhoid fever was, with other matter that had become
objectionable to the system, got rid of by the attack of
sickness. A case generally illustrative of this class of
■occurrence was rejencly recorded in the British Medical

NO. 1321, VOL. 51]

Journal. Four friends had an oyster supper on November
5. Two of them lived not far apart, but the others had
nothing in common as regards residence or an) thing else.
On November 23 three of them sickened, and they were,
later on, all found to have typhoid fever. Ore of the
patients, during convalescence, disclosed both his
profession and his views by re-naming his malady
" bivalvular disease."

Amongst leading medica'i men who have adopted the
view that oyster* are a source of typhoid fever, we may
name Sir William Broadbent, who early this year
announced that from time to time he had seen cases of
typhoid fever "apparently attributable to oysters,'' but
that during the course of last autumn the evidence as to
the communication of the infection through this agency
has been of such a character as to produce "convic-
tion " in his mind.

This naturally leads us to ask how the oyster becomes
the vehicle of such a disease ; and the evidence already
forthcoming on this point is such that we could only
wonder if typhoid fever were not occasionally conveyed
to those who eat this favourite mollusc in an uncooked
foriTi. Investigation of some of the river estuaries and
other places where oysters are cultivated and prepared
for market, would almost lead us to believe that con-
ditions favourable to typhoid fever were deliberately
chosen for the purpose. Indeed, it is notorious that a
number of our British oyster-beds are in such relation
to sewer outfalls, that the oysters must of necessity be
bathed in a solution of sea-water and sewage at every
tide. According to a commissioner appointed to inquire
into this matter by the British Medical Journal, a well-
known Essex oyster fishery has " a sewer discharging be-
tween oyster-beds on either side " ; and at a " health-
resort " (!) on the same coast, it is a common practice to
moor the oy ster-bo.\es to a pier or groyne, within a few feet
of which the evidences of sewage are too palpable to be
specified. In both the places referred to, the typhoid
fever poison, which it is known finds access to drains,
had had ample chance of foulirg the sewers in question.

It has been alleged, on the evidence of certain recent
bacteriological investigations as regards the contents of
London sewers, that the organism producing typhoid
fever cannot live and multiply in sewers. But the
organism has been found in sewers ; it also lives
in sea-water ; and the fact remains that sewage bathes
our oysters during cultivation to an extent that is
essentially disagreeable, and that ought not to take
place ; and, also, that typhoid fever follows the use of
oysters so cultivated. It may also be alleged, as is done
by certain oyster-growers, that sewage is fatal to the
oyster itself. In answer to this, we can only say that
such evidence as we have obtained, as to some of our
oyster-beds, is absolutely opposed to this statement ; and
not only so, but we know of more than one instance
where the oysters are deliberately brought from the beds
to fatten in still nearer proximity to outfall sewers for a
week or more preliminary to their sale. In brief, if
sewage and noxious mitrd-organisms can be retained in
the beard and other portions of the oyster, or in the
"juice," which is so much relished, everything seems
contrived to secure such retention of filth at some of our
oyster fisheries.

Doubtless the same applies to many foreign oyster-
beds. Indeed, the recent experience embodied in a
report by Prof. W. N. Conn, as to an epidemic of typhoid
fever amongst the students of a college at Middletown,
Connecticut, not only supplies convincing evidence of
this, but it affords the most connected and complete
proof of "oyster-typhoid" as yet published. Quite an
epidemic of typhoid fever occurred amongst the students
of certain fraternities, and amongst a number of their
friends who had Joined them at their " initiation sup-
pers," but who had subsequently returned to their distant

592

NA TURE

[February 21, 1895

homes, where they sickened. The incidence of the
epidemic was on those fraternities only who had included
raw oysters in their menu ; and even amongst these some
marked escapes were in persons who, for one and an-
other reason, had not consumed oysters. The suspected
oysters came from Long Island Sound, where they had
been put to "fatten" in a fresh-water estuary within
400 feet of a sewer known to have been receiving typhoid
material. The last piece of evidence bearing upon this
subject comes from an official source. It is announced
that, on the strength of a report by the .Medical Officer
of the Local Government Board, as to the diffusion of
cholera in England during 1S93, which report is now
passing through the press, an inquiry has been com-
menced into the circumstances under which oysters are
cultivated and stored round our coasts. The reference
is clearly to the serious outbreak of cholera at Grimsby
and Cleethorpes, and to the diffusion of the epidemic
from those places, whence a large distribution of o>sters
and other shellfish is constantly in progress.

Whatever be the outcome of the inquiry which has
been instituted, it is certain that two questions will come
to the fore : (i) the need for control over our oyster-beds,
and (2) the desirabi lity or not of allowing crude sewage to
be discharged direct into the sea, or into tidal estuaries.

NOTES.

Sir Henry Roscoe has been made Chairman of the Select
Committee of the House of Commons appointed to enquire
whether any, and what, changes in the present system of weights
and measures should be adopted.

We regret to announce that Mr. John Whitaker Hulke,
F. R. S. , president of the Royal College of Surgeons of England,
died on Tuesday, from broncho-pneumonia. An obituary notice
in the Times furnishes us with the following particulars with re-
gard to his career. Mr. Hulke w.is born in 1S30, and was the
elder son of a well-known and hii;hly-csleemed surgeon at Deal,
where his family had been settled for several generations. He was
educated at King's College School, and subsequently spent two
years in Germany, where he thoroughly acquired the language.
.\fter a varied experience as surgeon to the hospital at Smyrna,
during the Crimean War, ani in King's College Hospital, he
migrated to Middlesex Hospital. In 1859 he received the
Jacksonian prize of the Royal College of Surgeons for his Essay
on Diseases of the Retina, and soon afterwards he brought out
a treali-c on the ophthalmoscope, then a novelty in eye-practi ce.
This led to his being regarded mainly as an ophthalmic surgeon;
but he contributed to general surgery in the Medico-Chirurgical
Transactions, and joined Mr. Holmes in editing the third edition
of his "System of Surgery." He was elected a fellow of the
Koyal Society in 1867. In 1876 he was appointed an examiner in
anatomy and physiology at the College of Surgeons ; and in 1S80
became a member of the Court of Examiners, an office which
he held for ten years. In 1 88 1 he wa> elected a member of the
Council ; and, after twice serving the office of vice-president, he
became president in 1893, and has died in office. He had been
preiidenl of the Pathological and Ophthalmological Societies,
and at the time of hi.< death was president of the Clinical Society
and librarian of the Royal Medical and Chirurgical Society. Mr.
I lulke was, however, much more than an accomplished surgeon.
He was a good comparative anatomist, botanist, and geologist ;
.ind wa» at one time president of the Geological Society of
which he was elected the Trca.suicr on February 1$. He was
an artist in water colour, and was able both to model in
clay and to carve in marble. His loss is a real one to the
medical profession, in which he was esteemed as a man of the
highest probity and sagacity.

NO. 1321, VOL. 51]

We notice the death, at the age of eighty-eight, of a gifted
mathematician, the Rev. T. P. Kirkman. He was elected a
Fellow of the Royal Society in 1857.

Tiii; following deaths have occurred among scientific men
abroad: — Dr. Gerhard Kriiss, Extraordin.iry Professor of
Chemistry in the Univeisity of Munich. M. Jules Rcgnauld,
Professor of the Paris Faculty of Medicine, at the advanced .ige
of ninety. The Rev. J. Owen Dorsey, a well-known ethno-
logist, at Washington, February 5. Prof. Dorsey had been con-
nected with the liareiu of Ethnology, sine: 1S77. He was the
president of the .\nthropological Section of the -Vmerican
.\s^ociation for the Advancement of Science in 1893. We
also have to record the death, at the early age of forty-
five, on January 28, of Dr. F. Schmitz, Professor of Botany at
Greifswald. For many years past. Dr. .Schmitz had turned his
attention chiefly to the study of the .Alg-t, and especially of the
red seaweeds or Floridea;, to our knowledge of the life-history
of which he had made substantial additions. He published,
in the year 1877, an account of the formation of auxospores in
the diatoms, and, in 1S79, a description of the green Algx of
the Gulf of Athens.

Prof. L. Guignard, President of the Botanical Society of
France, has been elected to succeed the late Prof. Duchartre in
the Section de Botanique of the Paris Academy of Sciences.

Lord R.avh;ic.ii will deliver a course of six experimental
lectures on " Waves and Vibrations," at the Royal Instituiion, on
Saturdays, March 2, 9, 16, 23, 30, and .'\pril 6. He will also de-
liver the Friday evening discourse on April 5, when his subject
will be " Argon, the New Constituent of the Atmosphere."

A NEW thallium mineral has just been described, under the
name of Lorandite, by Prof. Krenner, of Buda-Pcsth. The new
mineral occurs sparingly, in association wi.h realgar, at Allchar
in Macedonia. It is found .is transparent crystals belonging
to the Mono-iymmetric system, and having the form of plates 01
short prisms ; its colour varies from cochineal-red to kermesite-
red. The mineral proves on analysis to cjrrespond to the
formula TI.-\sS._,, and contains 59 5 per cent, of thallium.

We have received from the Russian Chemical Society a
pamphlet, devoted to the description of tlie new chemical
laboratory which has been erected at the .St. Petersburg
University. The laboratory has been built in accordance with
the requirements of modern scientitic investigation, and has
cost £'i2,-]20. All branches of research have separate large
halls, special rooms being allotted to physical chemistry and
accurate physical measurements. .Mthough the laboratory is
behind many of the largest laboratories of West Europe, it
has the advantages of perfect arrangements for each separate
worker, and it decidedly has no rivals for the perfection of
ventilation. The total amount of warmed air supplied to all
the halls of the building attains 823,000 cubic feet per hour, so
that the air will be totally changed from one to five times per
hour in each separate hall.

I'm. Russian Geographical Society awarded, at its inceling
of January 30, the Constantine med.il to S. N. Nikitin for his
numerous works on the geology of Russia ; the Count Liitke
medal to P. K. Zalesskiy for geodetical work in Turkestan ;
the great gold medal, to N. .V. Karysheff for his work, "The
Land rented by the Pt.isants" ; nml the Prjevalsky premium, of
/60, to V. A. Obrucheff for his last journey in Turkestan and
Central Asia. Small gnld medals were awarded to the French
geodcsist, M. DelTorges, and the .-Vuslrian geodesist, Baron
Sterncck, for their pendulum nbscrvalions in Russia, and to M.
Sicrosjiwski fur his MS. on the Vakutcs ; and the great sdver
medal nf Prjcvalsky's name to Baron Toll and Lieutenant
Shileiko, for their last journey to Arctic Siberia. Eleven silver
medals were also aw.inlcd for mimr works.

February 21, 1895 J

NATURE

39:

Severe frost has continued in nearly all parts of the British
Islands, but in England and Ireland the cold was rather less
intense last week. The frost has now continued for over four
weeks, and although the period is shorter than in some other
frosts during the present century, the intense cold experienced
has been seldom equalled. There were no instances of tem-
peratures below the zero, as in the preceding week, but read-
ings of 20 , and even 30', below the freezing point have been
recorded. At Greenwich the mean temperature since the com-
mencement of the frost is 28', and the mean of the night read-
ings is only 22°. Very little snow has fallen in any part of the
British Islands, but the ground is still covered with snow from
the fall during the earlier part of the frost. The type of
weather has undergone a very considerable change, and the
last few days have been much less cold, although frost occurs
each night. The European anticyclone appears to have
thoroughly given way, and in the course of two or three days
the barometer has fallen to the extent of nearly an inch over
Scandinavia. An anticyclone is, however, situated over the
British Islands, and while this continues frost is still likely to
be experienced.

At the meeting of the Anthropological Institute on February
12, Mr. Brabrook drew attention to the work of the Ethno-
graphic Survey Conmitlee of the British Association, on which
the Institute was represented by Mr. Francis Galton, Dr. Gar-
son, and himself. He said the committee had been successful
in obtaining a long list of places suitable for survey, and had
prepared an octavo pamphlet, of twelve pages only, which gave
comprehensive instructions to those who.were willing to engage
in it. What the committee now desired was to increase the
number of observers, and he appealed to the members of the
Institute for assistance in this respect. The committee were
especially anxious to induce medical men to interest themselves
in obtaining the necessary physical measurements in suitable
places. Fo r this purpose, they would be glad to furnish instru-
ments, and render any other assistance that might be necessary
and practicable. All their experience had shown them how
valuable the results of their work would be likely to be, and
how desirable it was that it should be proceeded with without
delay.

The magnanimous spirit which the Academy of Natural
Sciences of Philadelphia has shown towards the circular sent
out by the Royal Society, asking for co-operation and suggestions
^an making a subject-catalogue of scientific papers, is an indica-
tion of the unity of the interests of scientific societies. A report
has been adopted by the Academy to the following effect : —
(l) That a catalogue ol scientific papers as proposed by the
Royal Society is desirable, and that international co-operation
should be engaged in its preparation. (2) That in order to
secure uniformity in all parts of such a catalogue, a central
bureau, as suggested by the Committee of the Royal Society,
appears to be necessary, rather than that separate portions of
the catalogue should be prepared by various institutions, such
central bureau to be under the direction of the Royal Society,
from which the proposition emanates ; all publications of
societies and monographs to be sent to such central bureau ;
the expenses to be met by returns from the sale of copies of the
catalogue. (3) That such a catalogue should be classified, and
should be issued at least once a year, each volume to be pro-
vided with an alphabetical index. (4) That the scope of such
a classified catalogue should embrace the various yearly biblio-
graphies of special sciences now issued. (5) That whenever
translations or summaries are believed to be desirable, English
should be made the basis of the catalogue.

The fragility of human promises is proverbial. The follow-
ing dialogue, which took place in the House of Commons on

NO. 132 I, VOL. 51]

Monday, furnishes another illustration of this quality : — Mr,
Bartley asked the Chancellor of the Exchequer whether work
was resumed last autumn at South Kensington Museum, as
promised by him, so as to leave everything ready for the com-
mencement of those buildings as soon as the money was voted
by the House of Commons ; and what sum was to be taken in
the coming year's Estimates for the completion of those build-
ings in accordance with the pledge of the present President of
the Local Government Board in March, 1894, on behalf of the
Government. The Chancellor of the Exchequer said the de-
mands upon the Estimates under other heads had proved so-
heavy that it had been found necessary to restrict the expendi-
ture on bricks and mortar to the lowest possible point, and he
feared that it would not be possible to undertake any large
expenditure in connection with South Kensington Museum at
present. Mr. Bartley : May I ask the right hon. gentleman
whether it is not the fact that last year a certain estimate was
allowed to pass on the distinct pledge from the Government
that this year there would be a vote for this building? The
Chancellor of the Exchequer : It was intended to do so, but,
as we were reminded the other night, we ought to cut our coat
according to our cloth, and the hon. member must allow me to-
know what our cloth is.

The anniversary meeting of the Geological Society was held
at Burlington House, on Friday, February 15, when the medals
and funds were awarded as follows : — The Wollaston Medal, to
Sir Archibald Geikie, F.R.S. ; the Murchison Medal, to Prof.
G. Lindstrnm, ; the Lyell Medal, to Prof. J. F. Blake ; the
Bigsby Medal, to Mr. C. D. Walcott ; the balance of the pro-
ceeds of the Wollaston Fund, to Mr. W. W. Watts ; that of
the Murchison Fund, to Mr. A. C. Sewaid ; a moiety of the
balance of the proceeds of the Lyell Fund, to Mr. P. F. Ken-
dall ; and the remaining moiety to Mr. B. Harrison. The
President delivered his annual address, the subject bearing on
the Pala:ozoic Crustacea. The following is a list of the officers
and Council elected at the meeting for the ensuing year. (The
names in italics represent new officers and members of Council.)
President: Dr. H. Woodward, F.R.S. Vice-Presidents: Prof.
A. H. Green, F.R.S., VV. H.HuiUston, F.R.S., R. Lydekker,
F.R.S., Lietit-Gemral C. A. McMahon. Secretaries: J. E.
Marr, F.R.S., J. J. H. Teall, F.R.S. Foreign Secretary ;
J. W. Hulke, F.R.S. Treasurer; Dr. W. T. Blanford,
F.R.S. Members of Council: H. Bauerman, Dr. W. T.
Blanford, F.R.S., Prof. W. Boyd Dawkins, F.R.S., Sir John
Evans, K.C.B., F.R.S., Prof. A. H. Green, F.R.S., Dr. J,
W. Gregory, R. S. Herries, Dr. G. J. Hinde, T. V. Holmes,
W. PL Hudleston, F.R.S., J. W. Hulke, F.R.S., Prof. J. W.
Judd, F.R.S., R. Lydekker, F.R.S., Lieul.-General C. A.
McMahon, J. E. Marr, F.R.S., H. A. Miers, K. 7. N'ewton,
F.R.S., F. Rutley, J. J. H. Teall, F.R.S., IV. mutakcr,
F.R.S., Rev. II. II. Winwood, Dr. II. Woodward, F.R.S.,.
H. B. Woodward.

The first scientific account of the Chilo-.\rgentine earth-
quake, which has reached Europe, is probably that written by
M. A. F. Nogues (Compics rcntim, vil. cxx. 1895, pp. 167-
170). The earthquake was remarkable for its intensity ani
long duration, the amplitude of the oscillations, and the
absence of subterranean sounds. The epicontral zone is-
elliptical in form, its longer axis being directed nearly north
and south, and passing by Rioja, San Juan, and Mendoza. The
fiist two of these towns were severely damaged, and a large
number of persons in them were killed and wounded. The
boundary of the disturbed area is as yet undetermined, but it
must have included a great part of the Argentine Republic and
of the north of Chili. Within the epicentral area, the duration

394

NATURE

[February 21, 1895

of the shock was fifty-five seconds ; at Santiago Observatory,
where it was reg istered by a seismograph, ihe duration was
10.403., and the amplitade of the oscillations 2°5 cm.

Thk Revue Scientifi,jue contains a full discussion of the cause'
of mountain sickness, by M. H. Kronecker, who was sent to
investigate the conditions under which the proposed railway to
the top of the Jungfrau could be worked without endangering
human life. M. Kronecker and six other persons from Berne
•wiire carried from Zermatt to a point near the summit of the
Breithorn, 3750 m. above sea-level. It was proposed to reach
the summit itself, but it was impossible to proceed without ai-
ditional carriers, the work bein^ mu-h more laborious at high
altitudes. But at the altitude reached, all the symptoms of
mountain sickness had shown themselves — acceleration of the
pulse and of respiration, desire f ir rest, even after a very slight
effort, and headache. M. Kronecker arrived at some interesting
conclusions regarding mountain sickness. It sets in at altitudes
\-arying with different persons. Beyond 3000 metres it attacks
all persons as soon as they indulge in the least muscular effort,
but children and very old people are much less subject to it than
others. It also varies with the character of the mountains, being
usually less serious on isolated peaks. Prrsons in good health
can stand passive transport to about 4000 m. without incon-
venience, but they should not remain more than two or three
hours at the top. .A. prolonged sojourn may be disastrous in
its effects upon health, as it proved to be in the case of Dr.
Jacottet. For the purposes of the railway, M. Kronecker
recommends that nil guards and other officials should be care-
fully selected and, if possible, acclimatised or frequently changed
between the stations. Finally, the summit station should be
arranged so that no further ascent whatever is necessary to get
the full benefit of the view.

At a recent meeting of the Sociele Fran9aise de Physique,
M. de Kowalski read a paper on the conditions necessary for
the production of katho le rays. Starting fro n an experiment
dne to Goldstein, in which in a vacuum tub» having a constric-
tion at its middle, it is found that the kathode rays are formed
not only at the negative electrode, but also at the constriction,
the author hai made several experiments. usin» tubes of different
shapes. He fin Is that wherever the electiic discharge is suffi-
ciently dense, as near the electrodes or in a capillary tube joining
the two parts of a vacuum tube, kathode rays are produced.
These rays are propagated in straight lines, are deviated by a
magnet, and produce a bright p\tch where they strike the glass.
The author has also succee led in obtaining kathode rays in a
tube without e'ectrodes. This tube had somewhat the shape of
an elongated hour glass, and was placed alongsi Ic a di-charger,
through which "Tcsla currents" were passed. Under these
circamttanccs katho le rays are produce I at either end of the
capillary tube forming the central part of the vacuum tube. M.
de Kowalski concludes from his ctperimenis (1) : that the pro-
duction of kathode rays is not connected with the disintegration
of metallic electrodes in a rarefied gas ; {2) that these rays are
produced wherever the dcn<iiy of the discharge is sufficiently
great ; (3) that the direction of the rays is the same as (hat of
the lines of flow of the current at the point where they arc
produced, and that they are propigaied in the oppo-itc direc-
tion 'o that in which poiiiivc electricity i'l supposed to flow.

At the same meeting at which the above pnpcr was read, M.

Curie described tome experiments lie had made to see whether

li^hl rays were deviated by a m.ignetic field in the same manner

'■de rays, lie has ohiaineii no deviation, although his

us prrmi'ted him to p»s« the light rays for a distance of

20 QUI, in a field having an intensity of l4"ocio units, the direc

lion of propagation of Ihe light being pcipcndicular to the lines

NO. 132 I, VOL. 51]

of force of the magnetic field. The experiment was made in
air, as well as in carbon bisulphide in which sulphur had been
dissolved. The author, although he does not think the above
experiments are conclusive proof that kathode rays are radiation
of a different nature from that which constitutes light, yet thinks
they tend to show that there is some difference. FurthermoTC,
if the kathode lays are analogous to light rays, it is difficult to
explain ihe absence of double refr.iciion when a magnetic field
acts on the kathode rays.

The triple number, pp. 10-12, of the BulUtitt of the
Botanical Department, Jamaica, is entirely occupied by a list of
the more interesting trees and shrubs, 109 in number, grown in
the Botanic Garden at Castleton, near Kmgslon.

In the most recent part of the Records of the Botanical Survey
of India, the Indiun Government publishes a report of a
Botanical tour in Kashmir, by Mr. J. F. Duthie, director of
the Botanical Department of Northern India, accompanied by
a map.

The Bulletin of the Royal Gardens, Kew, No. 96, for
December, 1894, contains an interesting article on " Cultural
Industries in Dominica," an island which, since the abandon-
ment of the coffee plantaiions, which were at one time its
staple industry, is very far from yielding the economical pro-
ducts which might be expected from its climate and the
fertility of its soil. .X. brief account is given of the four
Botanic S'ations in the Leeward Islands, those of Antigua,
St. Kitts, Dominica, and Moiitserrat.

The 1895 Aniiuaire of the Royal Observatory at Brussels,
edited by M. F. Folic, has been received. The Annuaire is
is second only to that published by the French Bureau des
Longitudes. It comprises ephemerides containing the principal
astronomical d.ita for 'he current year ; geographical, meteoro-
logical, and other statistics; physical constants; and several
articles, among them being three by M. Folic, _on diurnal^and
annual aberration.

The Smithsonian Report for 1893 has recently been issued.
The report comprises a selection of miscellaneous memoirs
embracing a considerable lange of scientific investigation and
discussion. This collection of reprints and translations, running
into very neirly seven hundred pages, contains articles of
interest to workers in all branches of science. Among the
contribuiions to the Report is a monograph on "North
.Vmerican Bows, .\rrows, and Quivers," by Dr. O. T. Mason.
The paper, which is illustrated by lifty-seven plates, deals with
the types of bows, arrows, and quivers of the North American
aborigines, with incidental references to similar forms found
eKcwhere.

Messrs. J. and A. Churchill have nearly ready the
second volume ol "Chemical Technology," edited by Mr.
C. li. Groves, F.R. S., and Mr. William Thorp. This volume
is devoted to lighting by candles and oils, and is illustrated by
about 350 figures ; the section on fats and oils being written
by Mr. William Y. Dent; siearine, by Mr. John .Mc Arthur;
candle manufacture, by Messrs. L. Field and M. A. Field ;
the petroleum industry, by Mr. Boverion Redwood ; lamps,
by Mr. Boverton Redwood ; and miners' safety lamps, by
Messrs. Boverton Redwood and D. A. Louis. The third
volume of the same work, containing gas lighling, by Mr.
Charles Hunt, of Birmingham, and cleciric lighting, by I'rof.
Girnctt, of ihc Technical Board of the London County
Council, is in a very forward slate.

Messrs. Macmillan and Co. will publish early in March
the treatise on '• BesscI Functions and their Applications to
Physics," by I'rols. Gray and Mathews, which has already been
announced. The work, after an introductory chapter on the

February 21, 1895]

NA TURE

395

problems which gave rise to the functions, deals with their
properties, expansions involving them, semi-convergent expan-
sions, Fourier-Bessel expansions, complex theory, definiie
integrals, and the relation of the functions to spherical
harmonics. The physical apjjlicaiions embrace flow of heal
and electricity, vibrations of membranes, hydrodynamics,
electrical waves along wires, diffraction, and a number ol
miscellaneous problems. Numerical tables are appenaed, and
also the Tables of Functions with imaginary argument, which
have been prepared by Prof. A. Lodge for the British Associa-
tion. A note containing useful formulae for the calculation
of the roots of Bessel Functions and others related to them, has
been added from a manuscript placed at the disposal of the
authors by Prof. J. McMahon.

We have received Parts iv. and v. of Indian Meteorolo;^ical
Memoirs (vol. v.), containing the discussion of hourly observa-
tions made at Allahabad and Lucknow, forming a portion of the
harmonic analysis of the observations recorded at twenty-five
observatories in India, since the year 1S73. The investigation
is carried out in a most thorough manner, and there can be no
doubt that when the work is complete, and the results correlated,
much light will be thrown upon the laws which regulate
atmospheric movements in those parts. In any case, the dis-
cussion will take rank among-it the most important cfthe kind
hitherto undertaken by any country.

A COMPOUND of grape sugar with one of the acid radicle
derivatives of hydrazine recently prepared by Herr Siruve, a
pupil of Prof Curtius, is described by Dr. Wolff, of Berlin, in
the current Berichte of the German Chemical Society, and, on
account of its properties and mode of formation, appears
likely to be of considerable service in the commercial extraction
of pure dextrose from syrupy mixtures. It is first shown that
the sugars of the aldose type react with the acidylhydrazides to
produce an aldose-acidylhydrazide by direct addition with
elimination of a molecule of water. Thus, in the case of
dextrose and benzliydrazide the following equation represents
the change :
C,H,,.C : O.NH.NH.. -f O : QHi.Os =

CsHs.C.O.NH.N.CgHioOj ^- H„0.
When dextrose and benzh)drazide are digested with 96 per
cent, alcohol for five or six hours in a flask provided with
an uptight condenser, the new compound is produced in solution
in the alcohol, and upon subsequent evaporation it separates in
the form of acicular crystals, which can readily be purified by
recrystallisation from alcohol. The crystals melt at 171-172'
with partial decomposition. As Icevulose does not react with
benzhydrazide, pure dextrose can readily be isolated from the
mixture of Isevulose and dextrose in ordinary invert sugar by
utilising the aliove reaction. The invert sugar is evaporated
to a thick syrup, and the latter digested with alcohol and
benzhydrazide for about six hours in a reflux still. The alcoholic
solution is then evaporated over a steam-bath almost to dryness,
the Isevulose is extracted by washing with a minimum of alcohol,
and excess of benzhydrazide removed by means of ether. Pure
dextrose-benzhydrazide is then obtained in good crystals by two
reciystallisations from alcohol. The recovery of dextrose from
this compound with benzhydrazide is a very simple matter, for
the compound is immediately broken up by boiling water into
dextrose and benzhydrazide. It is found convenient in practice,
however, to remove one of the products of the dissociation,
the benzhydrazide, by precipitation as the insoluble benzal-
benzhydrazide by means of benzaldehyde, which is found to be
a most valuable reagent for the purpose, .\fter filtration the
liquid is evaporated to dryness, dissolved in cold water, whereby
any traces of unprecipitated benzal-benzhydrazide are left
behind, and again evaporated to dryness. The last | traces

NO. 1321, VOL. 51]

of impurities, chiefly benzaldehyde and benzoic acid, are
finally removed by dissolving the dextrose in alcohol and pre-
cipitating with ether. The dextrose eventually obtained by
evaporation of the clear solution is quite pure. Dr. Wolff
lastly states that the above is a general process for separating
aldoses from mixtures of sugars, and he is experimenting with a
view to its adoption on the large scale.

The additions to the Zoological Society's Gardens during the

past week include a .Snowy Oivl (Nycfca scandiaca) from
Norway, presented by Miss Wright ;' a Dunlin [Trin^a alpitti),
British, purchased.

OUR ASTRONOMICAL COLUMN.

Mars in 1894. — Si^mr G. Schiaparelli remarks, in No. 3271
of the Aslroitomisihe Nachrichten, thitthe unfavourable state of
the atmosphere during the o jp jsiti >n of Mars lau yeir ren lerei
magnificaiio is beyon 1 230 impossible except in rare instances.
Speaking generallv, he says that the "seas" were less pro
nounced than in 1S77, and the " canals" were better visible
in 1894. and seen in greater numbers. Sjme of the largest
ones showed faint traces of dou "ling, but, with the mignifying
powers used, nothing coul 1 be male out with certainty on this
point. The southern pole ca 1 b 'Came invisible in the i8-inch
Milan refractor at the end of October. On October S it had
already become very faint. Tfie total disappearance cannot
have been later than October 29, i.e. on the 59th day after
the southern solstice of the planet. This is unusually eirly.
In 1877-78 it was well seen as late as gS days after the solstice.
In the present case it is preHy certain that the whole of the
southern pole cap was melted. A great change was also
observed in the isthmus or peninsula of Hesperia, which
separates the Mare Tyrrhenum from the Mare Cimmerium.
It was apparently separated into two unequal portions by a
newly formed.channel. The Mare Sirenum, which in October,
1892, had been separated into two pirts, was in October, 1S94,
seen to have resumed its ordinary aspect. But on November
21 the sepiration had reappeared. "This fact," says
Schiaparelli, " and other analogous ones which I have observed
in previous oppositions, lead to 1 he conclusion that the abnormal
chang-s in the markings of Mars do not take place by chance
and without regularity, but that the same variation may
reappear, with t le same aspect, even after a long mterv.al of
time. The lorm and extent of such changes is determined by
some element which is stable, or at least periodic."

Novel Methods in Photometry. — The determination of
the times of exposure of a photographic plate which are
required to produce the same density of film when exposed to
ditlerent light sources, forms the basis of the methods recently
adopted by Dr. Janssen for inve-tigating the brightnesses of
the heavenly bodies (Bull. Mens. Soc. Ast. de France,
February). In the case of stars, the plate is placed a little
within the principal focus of a telescope; so tnat a disc, or
" stellar circle," replaces the almost point-like image ordinarily
obtained ; a series of exposures is made on one star, and an-
other series on the star to be compared with it : the two images
of the same density are thus identified, and the photographic
brightnesses of the two stars are inversely as the durations of
the corresponding exposures. To compare the light of a star
with the sun, an opaque screen, pierced with holes of the same
size as the stellar circles, is placed in front of the photographic
plate, and these holes admit suni ight to the plate at the moment
a triangular aperture in another metal plate is passed over them
on releasing a spring ; in this way a series of circles of increas-
ing intensity is impressed on the plate, and can be comp.ired
directly with the stellar circles.

In its application to nebulae, Dr. Janssen's method promises
to be of great value. On the same plate which has been ex-
posed to a nebula, a series of "stellar circles" is formed by
directing the instrument to a star in ttie neighbourhood which
shows no signs of variability. In the future, when one wishes to
obtain a photograph of the nebula which will be strictly com-
parable to one taken previously, it will only be necessary by
means of stellar circles to determine the exact exposure which
should be given.

From an inquiry into the photographic luminosity of the tail

596

NA TURE

[February 21, 1895

of comet /■ iSii, Dr. Janssen fiorts that ihe intensity decreised
in a ratio between the fourth and sixth power of the distance
from the nucleus.

Atmospheric Dispersion'. — The fact that the image of a
star as seen in a telescope is drawn out into a short vertical
spectrum, with the red end uppermost, was noticed as long ago
as 1729 by Bautjaer, 'and the effect of the difterence in colours
of stars upon refraction appears to have been indicated in a
general way by Lee in 1815. Even in small instruments this
at-nospheric spectrum is very noliceab'e in ihe case of bright
stirs at low altitudes, but, if necessary, it can be corrected by
means of a thin prism placed in front of the eyepiece, or by
employing an eyepiece of the form deviled by the lale Sir
t>eorge .■Xiry. In a recent paper {Monthly Notices R.A.S.,
January), Dr. Kambaut points out the importance, in these
days of extreme accuracy, of introducing a correction for
atmospheric dispersion — according to the varying colours of
stars — more especially in connection with observations of two
stars in close proximity, as in measures of double stars, and
observations for parallax. The claims of this hitherto rather
neglected factor appear to be fully substantiated by a series of
measures at different hour angles of S Cygni, in which double
star the colours of the components are strongly contrasted ;
they "show clearly a systematic difference affecting the dis-
tance between them, of the sort, and in the direction, that
theoretical considerations indicate." Dr. Rambaut also shows
that the systematic differences deperding upon hour angle in
the measures for the parallax of o Cenlauri by Drs. Gill and
Elkin, which they corrected by empirical formula', are due to
a diffcrenc: in the mean refrangibility of the light of the star
and of the comparison stars. Further con5rmation is derived
from a re-discussion of the Dunsink observations on the
parallax of 61 Cygni, and the resulting value is corrected from
o"'46s to o"'400.

.•\n ingenious method of measuring atmospheric dispersion
has been devised by M. Prosper Henry, and values determined
for different colours (N'atikf. vol. xliii. y. 4001.

I

Let me bring before you one of the most perfect pieces
of workmanship in the world constructed to investigate
the phenomena of the heavens. It is a photograph of the
Lick Oli'^ervatory, situated at an elevation of 4000 feet on
Mount Hamilton. Mr. Lick, the founder, was a very ambitious
man. He was, I believe, an hotel-keeper at San Francisco, but
however that may be, he has made his name immortal by help-
ing on the progress of mankind. I wish we had some hotels
like the San Francisco hotel in this country, and some Mr.
Licks, because then some Englishman might immortalise him-
self in the same way. This, then, is the magnificent locality in
which a great deal of the work that I shall have to refer to has
been done. The principal instrument of this great Observatory
is a refracting telescope having an object-glass three feet
in diameter, and a lube fifty-four feet in length. This is
practically the most important telescope in the world at the
present moment, and to give you an idea of the wonderfully

THE SluYS PLACE IN NATURE.'
I.
AM anxious to give in these lectures a statement, as clearly
and as judicially as I can, of the discussions which have been
going on since these results were published, to show what
holes have been picked in the new views, and what new
truths may be gathered from the new work which has now been
brought to bear upon the old, so that as a result the |)lace I
have given to the sun among its fellow stars may be justified
or withdrawn. These lectures will be different from the
former ones, inasmuch as I then attempted to give you
a piece of quiet history of several regions of fact and know-
ledge which had been well surveyed and mapped, and had
become part and parcel of the common property of mankind.
But now I shall have, in considering the discussion, rather to take
you with me into the forefront of those who are fighting the
battles on the confines of the unknown. I have to bring you news
from the front, something like that which we arc promised
to-morrow or the next day from Port Arthur. I have to .show
how the battle is waging, who has lost, what positions have
4>een occupied, and what things new and true and beautiful
have been wrested from the unknown region ; and I am
the more anxious to do that because it enables me lo bring be-
fore you the enormous advantages under which such work is now
carried on ; advantages in that now, when any question is put
to any part of the heavens, we know that there are many good
workers employed under the best possible conditions to get the
particular information that we want ; besides these advantages,
in every branch of inquiry we find advances gigantic, marvellous,
almost beyond belief.

I am sorry lo .say that in this work the centre of gravity of
theactivity has left our country and has gone out West. We have
to look toour American cousins for a great deal that wc want to
know in these matters, for the reason that now they not only have
the biggest telescopes, and most skilled observers, but also they
have been wiser than we — they have occupied high points on the
earth's surface, and thus got rid of the atmospheric diflicullies
under which we suffer in England, and especially in London.

> t !*:» of a course of IrclurcA lo working men

• rology during Novcmt>cr and December,

tS^i

;)

I'ic. 4-— Spectroscope atLiclicd 10 the cyc-cnd of tlic I.ick Telescope.

broad way in which the authorities have gone to work,
I need only state the loUowing fact. Some of you who
have been in an observatory may remember that it has some-
times been very dilVicult to get the observatory chair at the
right height, or in the right position, for observing a star or any
celestial body with any comfort. The Americans get oyer this
by simply rai-ing the floor. liy means of hydraulics the
enormous floor, some 80 feet in diameter, is moved up and down
with the chair. The i'nporlance of spectroscopic work has not
been lost sight of in the equipment of the Oi-servaloiy, and a
very powerful spectroscope can be used in conjunction with the
great equatorial for observing or photographing the spectra of
ihe various celestial bodies (I'ig. 4).

One of the most important telescopes in Knglanil at present
is Dr. kobcrls" reflector, with which several majestic represen-

NO. I 32 I, VOL. 5 1]

February 21, 1895]

NA TUR£

597

tations of ihe heavenly bodies have been produced ; these I
shall have to show you at one time or another in relation to
different branches of our subject. In this instrument (Fig. 5) a
reflecting telescope of 20 inches aperture is combined with a
refractor of 7 inches aperture. The refractor is used as a
guiding telescope, and ensures that the imasjes of the stars and
tiebuKc fall on the same part of the photographic plate which
is being exposed in the refleding telescope throughout the whole

I I.,, :, — I'l. Roberts' twin telescope.

lime of the e.vposure. Even with the best driving clocks, such
a guiding telescope cannot be dispensed with when the ex-
posures are prolonged for the number of hours necessary in some
cases.

• i First for the nebulae. What is the difference, written down
in this way, between a nebula and a star cluster? A com-
parison of Figs. 6 and 7 will at once show that in the case of
a star cluster we have to deal with a collection of separate
stars, while in the case of a nebula there is a filmy sort of

Fig. t. — The Cluster 15 M Libr.-r, from .1 phol o'r.-iph hy Or. Kotirrts.

luminosity which is quite distinct from the neighbouring stars.
Here and there the nebulosity is suddenly brightened, but, as
I shall show hereafter, these condensations are not to be
regarded as stars in the ordinary sense. Here is Ihe
nebula of Orion, which we owe to th.it wonderful telescope of
Dr. Roberts. Several of you may have seen the nebula of
Orion with a telescope, but you have never seen it exactly like
this. Vou get here the idea which gave rise to the old notion
of a candle shining through horn ; this nebula is the one which,

NO. 132 I, VOL. 51I

on account of its brightness, spectroscopically gives us most
easily indications of those bright lines which for ever .<et at rest
the idea that we are dealing with solid or liquid bodies.

••Vt the beginning of the present century it was found that in

Fig. 7. — The spiral nebula in Canes Venatici, from a photograph by
Dr. Roberts.

order to get the spectra of stars the best thing to do was to
put a prism outside the telescope, and to let the light enter
the telescope and be brought to a focus after it had passed
through the prism ; and it is a most unfortunate thing, that the

ing nielhi '1 <it p':

prism.

neglect o( the application of this principle has lan'Jed us pro-
bably in a delay of fifteen or twenty yerrs in g.ilhering know-
ledge on I I>is subject. The whole credit of reviving this idea
is due to Prof. Pickering, of'the Harvard College, who since

398

NA TURE

[February 21, 1895

its application has been able, wiih the aid of the large (unds
that he has at his disposal, and the magnificent help which he
has accumulaled round him, to obtain practically the spectra of
all the stars down to the fidh or sixth magni'uHe in both hemi-
spheres. In a few years' time we shall be able to work on the
spectra of all the stars in both hemispheres, just as well as we
can at present deal » ith their magnitudes and positions by the
star charts.

An instrument of this kind (Figs. 8 and 9), having an aperture
of only 6 inches, has been in use at Kensington for some lime,
and some of the results which have been obtained by its aid are
shown in Figs. 3, 10, and II. They are absolutely untouched
photographs.

Without going into minute differences, we can, and, if
we are wise, we shall deal first of all with the larger differences
presented bythe various classes of stars which people space. Here
we have photographs of stars of different classes (Fig. 3). Vou
will understand from these photographs how perfectly justified
Rutherfurd and otheis have been in attempting to classify the

Fic. 9.— Details of objective prism.

Stan by means of their spectra. In Sirius we get one class of
stars, distinguished by the development of certain lines, which
are due to the absorption of hydrogen. In a Cygni the hydrogen
gas is represented quite distinctly, but the absorption there with
regard to certain lines is much more developed than in such
a star as Siriiu. In Arcturus the absorption of the hydrogen is
.almost hidden in an enormous mass of lines. Here again we
have another class, and it is not too early to remark that
Arcturus in its spectrum exactly resembles our own sun. Thus
we can «ay the sun is like Arcturus, not like a I lerculis, a Cygni,
and so on. -.-•^

Fig. 10 is an exemplification of the kind of result which is now
being obtained, and ihe kind of work which can now lie carried on
with regard totheminutcstruclureof thcscspec'ra. Onci.sthe star
Arcturus, and the other a star in the cnnsicllationol ihe Swan.
Vou 5ee at once that, if it is a quesliun of attempting to deter-
mine whether stars are like each other, or whether they are un-
like each other, and Ihe points in which ihcy differ, with the
resources of modern science at Ihe present moment — small

NO. I32I, VOL. 51I

pirtSHBT*^* ■■^B

1

I".. ,

y -

gar.'

-\

February 21, 1895 J

NA TURE

3Q9

as those resources are in some instances — we have really an
opportunity of doing a considerable amount of work. The
particular bit of work which is represented in this diagram is an
inquiry showing how the iron lines observed in the spectra are
represented in these different stars ; we can see whether the
condition of the iron vapour is the same in a star like Arciurus
as it is in a star likeyCygni. You will see that from this
point of view there is a great difference in the atmospheres of
these two stars.

The definition of the negatives obtained by means of the
objective prism is of such excellence that they may be almost
indefinitely enlarged, and this gives them a special value when
we come to investigate the smaller differences between stars
which have more or less resemblance to each other. Practically,
we are able to dispense with elaborate micrometric measure-
ments, and by placing the enlargements alongside each other,
to see at a glance which lines agree in position and which are
different.

NATHANAEL PRINGSHEIM.

"DOTANISTS throughout the world will have heard, with
-^ deep regret, of the death of Prof. Pringsheim on October
6, of last year. His name is inseparably a-sociated with the
modern progress of the science, and there must be many, who,
like the writer of this notice, can trace their first interest in
scientific botany, in no small degree, to the fascination of
Pringsheim's discoveries. Pringsheim was born in Silesia, in
1823. His career, though an active one, was unusually free
from official cares. Except during four years, when he was
Professor at Jena, he does not appear to have held any teach-
ing post of importance. Duiing the greater part of his scientific
life, his work was carried on in a private laboratory, founded by
himself at Berlin, and devoted entirely to the researches of
original workers.

Pringsheim was founder and editor, from 1858 to the time
of his death, of the famous J ahrbiicher fiir Wissenschaftliche

44

■15

1. a CYGKI.

2. 7 ORIONIS.

?^W

i; i

« If

■^■^

3. o TAURI. 1. a ORIOXI.S.

• Fig. II. — Portions'of stellar spectra, greatly enlarged.)

The spectra represented in Fig. 1 1 have been enlarged twelve
times from the original negatives, and on this scale the whole
of the visible spectrum would be more than a yard in length.
Here we observe, in the first place, the immense difference
between two groups of stars, one in which the lines are very
numerous, the other in which the number of lines is relatively
small. We also have an opportunity of studying the more
minute differences between stars like a Tauri and those like
a Ononis, and between stars like a Cygni and those like
7 Orionis. In some cases, differences which might easily be
overlooked abotjether in an examination of the negatives alone,
become apparent when the scale is enlarged in this way.

Thus, by n cans of the aids which have been placed at our
disposal, by the recent improved condition of our stock in trade,
and the wonderful diligence and skill of observers, chiefly in
America, who have taken up the new work, we are now in a
very much lietter position than we have ever been before to
investigate this subject. J. Norman Lockver.

(7(7 bi continued.)

Botanik, and was President of the German Botanical Society
from its first origin. He was among the many distinguished
foreign men of science who attended the meeting of the
Biitish Association at Manchester, in 1S87.

The scientific activity of Pringsheim extended over a period
of fully forty years (1S48-18S8), a time which covers what was
perhaps the most brilliant epoch in the history of botany. His
»oik began in the days when the science of histology was
being built up on the basis of the cell-theory of Schleiden and
Schwann ; he himself contributed essentially to its construction.
Piingsheim's greatest services to science, however, were in the
department of the morpholrgy and life-history of the lower
plants, a line of research in which he was unsurpassed. Com-
paratively late in life his attention became directed to physio-
logy, but in this direction his success was less conspicuous.

Pring'-heim's earliest contribution to science was his
Latin disseitation, " De forma et incremenio straiorum
crassiorum in plantarum cel)ul;i" (Linncca, 1S48), in which he
discusses a question much agitated at that time, whether the

NO. 132 1, VOL. 51]

400

NATURE

[February 21, 1895

increase in thickness of the cell-will takes place from without
or from within. He decides, chiefly from observations on the
cells of ih; testa in seeds, in favour of apposition from the
interior, a conclusion which no doubt holds good for the great
majority of cases, though the researches of Strasburger have
shown that this is not a universal rule.

Not long afterwards, Prin^sheim made his first investigation
of a question which continued to occupy him, at intervals, for
more than thirty years, namely, the development of the Sapro-
legniacex, a family which lies on the confines of ihe Alga: and
the Fungi. At that time the delimitation of genera and species
among these plants had fallen into great confusion. Prings-
heim's memoir of 1851 bears the title, "On the development
of Achlya frolifera," but its suhject was really a SafroUgnia.
The zoospores of this family had long been known, and their
re<tingspores had already been observed by Schleiden and
Nageii. Pringshcim, however, was the first to prove that the
two kinds of spore are produced by the same species ; he
watched the germinalion of the resling-spores, and saw that
they gave rise to the ordinary form of the plant, with its
zoospores. At that time he regarded it as an open question
whether these plan's are to be classified as .\lgce or Fungi ; they
are now assigned to the latler class, but placed near its lower
limit, where there has not been much divergence from the
original algal stock.

Six yeais later, Pringsheim discovered the sexual reproduction
of the Saprolegniace-Te, an observation of the greatest im-
portance, though his account was not free from mistakes, most
of which he corrected himself in subsequent memoirs. It is a
remarkable fact that in certain species of the family some indi-
viduals are entirely without male organs, and produce their
otjspores parthenogenctically. In others the antberidia are
present, but there is no penetration of the oogonium. The
question whether actual fertilisation takes place in aiij' Sapro-
legniace.u was the subject of a keen controversy between
Pringsheim and De Bary ; the latler, for reasons w hich we have
not space to enter into, held that the family, as a whole, is
afnganwui, i.e. that the sexual organs, even when present, have
lost their function. Pringsheim, on the other hand, maintained
that in the forms with fully developed antheridia true fertilisation
takes place by means of "spetmamoebx." The question was
under discussion up to the year 1883, and cannot even now be
regaided as finally settled. Pringsheim's observations of the
supposed amccboid male cells are not very convincing, but
neither is Ihe negative evidence against the occurrence of
fertilisation in the family deci^ive. The higher Fungi are
characterised, as most botanists now agree, by a total loss of
sexuality ; in Ihe .Saprolegniaceae we can, at any rale, trace ihe
beginnings of this retrogressive change.

It was, however, among the Algae themselves that Prings-
heim's chief triumphs were won. His earliest purely Algo-
logical paper was on the germinalion of the reslings|iores
of S/irn/!jra, in which he first demonslraled ihe interest-
ing fact that the embryonic plant presents a distinction of apex
and b.ise, which is quite lost in the later stages of its growth.
The supposed motile spores of Spirogyra (described in the
same paper, 1852) really belonged to a Chylridiaceous
paiasite. These inconvenient intruders had already misled
Pringsheim in some of his earlier observations on Sapro-
legniacex. In Ihe same year, he made out the reproduction in
an interesting little Alga {Calastnim) allied to the " Water-
nel."

Pringsheim's really fundamental investigations of the Alga:
begin, however, with the year 1855, when he communicated
to Ihe lierlin Academy a memoir on Ihe fertilisation and
germination of Ihe Algtc, and on the nature of sexuality. The
chief point of lhi« paper is the demonstration of Ihe sexual
icptoduclion of I'aiiihrria. Vaucher himself had discoveteil
the "anthers" at Ihe beginning of ihe century ; it was re-
•erved for Pringsheim to find the spermalor.oids, an<l loobserve
the act of ferlili-alion. The proof of such an advanced mode
of repro<luction in an unicellular (or rather non-cellular) plant,
was a startling discovery, and provoked some opposition
among those who had not Ihe .»kill \'> repeat Pringsheim's
obsetvalions. This paper fuilhtr contains researches on the
fertilisation of /iicu!, and on the sexual organs of Flnridca:
fwhich of course was only fully understood at a laler time), and
preliminary observations on the rcmaikable life-history of
CEdn^aniiim and llulboihtilt.
Theie latler discoveries were more fully announced in the

NO.

I 32 I, VOL. 51]

next year (1S56), and two years later the whole history was told
in a magnificent memoir, published in the first number of the
Jahrl>ii(her fiir \Vi:stnschafilichc Bolanik. Tins work is a
model for all such investigations, and has left very little for sub-
sequent observers to do, as regards these plants, which in some
respects present unique peculiarities. The Gidogoniacere
possess (in addition to the asexual zoospores) highly difleren-
tialed ova and spermatozoids. Many species are moncccious,
and a few dia^cious ; most, however, present a remarkable form
of dimorphism. Certain cells produce ova ; others (usually in
the same plant) give rise to small zoospores, which become
free, attach themselves to the oo^onia, or to adjacent cells,
and there germinate into dwarf male plants. Each of these
dwarfs consists of a single vegetative cell and an antheridium,
in which two or more spermatozoids are produced, by which
fenilisation is effected.

Another interesting point discovered by Pringsheim, is the
germination of the sexually produced resling-spores, which do
not grow directly into new plants, but give rise, each, to four
zoospores ; we thus have a case here, either of polyembryony, or
of alternation of generation, according to our interpretation of
the phenomena.

Two years later (in i860), Pringsheim published an equally
important memoir on another group of freshwater Alg.-e — the
Coleocha;tea;. These curious little plants, which grow on the
larger water-weeds, go through one ci cle of development in each
year. During the earlier part of the season, only asexual in-
dividuals, reproduced by zoospores, are formed. At the close
of summer the last generation produces sexual organs also.
After fertilisation (which is effected by spermatozoids) the
oospore passes into its winter rest, and then germinates in the
spring, giving rise, not to a normal plant, but to a paren-
chymatous, fruit-like body, in e.ach cell of which a zoospore is
formed. There is thus an evident analogy with the life history
of the Mosses, which Pringsheim at once recognised. Of all
Thallophytes, the Coleoch.-eleae show the nearest approach to
that form of alternation' of generations which is so general
among the Bryophyta. Whether this is anything more than an
analogy, is still an open question.

A controversial .-Vlgoloyical paper of the same date (i860) is
of interest, because the author opposes the view (held at one
lime by Thuret) that only a dytiamical reaction lakes place be-
tween spermatozoid and ovum. Pringsheim showed that the
two sexual cells undergo an actual material fusion, a fact which
lies at the root of all sound views as to the nature of the sexual
process.

A year later, Pringsheim added to our knowledge of the re-
markable course of development of the "Water-net" (Hydr,
dictyon), by tracing the history of those minute zoospores which
become free from the parent-plant, and give rise to resling-
spores. In this case, however, he overlooked the occurrence of
conjugation, which, according to a subsequent observer, lakes
place between these small motile cells.

In 1862, Pringsheim turned his attention to marine Alg.x, and
published some observations on the Red Seaweeds, in which
he rightly described the structure of the sexual organs. Their
function, however, was only demonstrated, five years later, by
Thuret and Hornet.

To the year 1863 belongs an important memoir on the
Characea-, a group of plants, which, though so popular as lexl-
b)ok types, is still a mystery as regards its relationships.
Pringsheim's observations were cliiedy in the proembryo and
allied structures. He established the existence of a striking
correspondence between these organs and the i)rotonema of the
Mosses.

After an interval of six years, he returned, in 1869, to
the investigation of the .Mg.x, and made known perhaps the
most important of all his Algological discoveries, that of the
conjugation of zoospores, a process which he regarded as the
primitive form of sexual reproduction in plants. 'This striking
iliscovery was first made in /'atiJorhia, one of the Volvocineic,
a family whch is often claimed by the zoologists, but which, in
its reproiluclive phenomena, bclrays the closest aflinity to
undoubted plants. The motile cells, which conjugate in pairs,
sonipiimcs difler considerably in size, while in other cases they
are almost exactly similar. I'he product of their union is a
resting-spore, which on germination ultimately, though not
direcily, gives rise to a new colony. Pringsheim observed the
details of the fusion of the sexual cells, and found that they
first become united by their anterior ciliated ends, which consist

February 21,

'«95j

NA TURE

401

of clear protoplasm. He compared this part of the conjugating
cell to the "receptive spot " of ihe ovum in the higher Alga:,
to the canal-cells of archegoniate plants, and to the synergida; of
Angiosperms.

The conjugation of motile cells has since been observed in
many other families of Alga?, of llie most diverse affinities, and
in several of these families we can now trace the advance from
this primitive fusion of like cell?, to the union of a differentiated
ovum and spermalozoid. Pringsheim's discovery has thus proved
to have all the far-reaching significance which his scientific
insight attributed to it, from the first. It has now become
customary to speak of active conjugating cells as "planogamet.v,"
a word which is useful, as indicating their sexual function, but
which must not be allowed to disguise their complete homology
with the asexual zoospores.

In 1S71, he discovered the male plants, and the pre-
sumable se.vual cells of Bryofsis, a marine Alga, allied to
Vaiicheria : the process of fertilisation however, has not yet
been observed.

Pringsheim's latest contribution to Aigology was his interest-
ing work on the course of morphological differentiation in the
Sphacelariaceoe, a group ol lirown .*Mga;, in which the progress
from filamentous to cormophytic structure can be traced
through a very complete series. His views on evolution were
akin to those of Nageli {cf. Nature, vol. xliv. p. 5S2).
He saw clearly the evidence of descent, but could not admit
that natural selection is a sufficient explanation. It seemed to
him that the highly differentiated Sphacelaria has nc advantages,
in the struggle lor existence, over the simple Ectccaypiis. He
held that the first deviations from primitive simplicity of
structure, are of a " purely morphological nature," and have no
demonstrable relations to any physiological functions.

Views of this kind are widely spread among German
naturalists. The greater, however, our knowledge of the
conditions of life in plants becomes, the less room is left for
these supposed "morphological characters," which are
probably, at most, nothing more than adaptive characters
which became fixed a long time ago.

We have endeavoured to give a connected account of
Pringsheim's Algological work. During the same period,
however, he had also made important contributions to science,
in other directions ; one or two of these must now be noticed.

A work bearing the date 1S54, on the structure and formation
of the vegetable cell, belongs to the period when the doctrine
of the multiplication of cells by division had just gained the
victory over the erroneous theory of free-cell-formation, so
pertinaciously defended by Schleiden. Pringsheim's researches
afforded valuable support to the new views. He observed cell-
division in both vegetative and reproductive cells of many .-Mga?,
as well as in the pollen- mother-cells ol Phanerogams. His
view of the formation of the cell-wall comes wonderfully
near to the conception of this process, which we have attained
at the present day.

Pringsheim's work on the morphology and development of
Salviitia \.i^6'i) is his most important contribution to ourknow-
ledge of the higher Cryptogams. He completely worked out
the entire life-history of this interesting plant, and a more
perfect monograph has never appeared. His observations
will always form the basis of our knowledge of Salz'ittia, which
is one of the most highly modified forms of Pteridophyta ; they
also throw great light on the embryology and development of
the class as a whole.

Pringsheim, in 1876, crowned his long series of morphological
investigations by a remarkable essay on the alternation of
generations in the Thallophytes, and its relation to that in the
Mosses. In the 0|)inion of the writer of this article, this is,
from a theoretical point of view, his most important work.

The essay was suggested by the experiments of its author on
the sprouting of Moss-fruits. These experiments were under-
taken by Piingsheim with the express object of determining
whether the Moss-seta could be induced to subserve vegetative
propagation in the same way as the Moss-stem, which it so
closely resembles anatomically. He found that the seta of
Bryiim and Hypiium, when divided, and kept in moist air,
developed a normal ]irotonema, from which true Moss-plants
arose. In other words, he succeeded in producing the sexual
from the asexual generation, without the intervention of spores,
thus establishing the first case of apos/toiy, our knowledge of
which has since been so much extended. In the meantime the
converse phenomenon of apogaiiiy had been demonstrated by

NC. I321, VOL. 51]

De Bary and Farlow, who showed that the asexual generation,
in certain Ferns, may arise from the sexual prothallus, without
the intervention of the sexual organs. These facts really
formed the groundwork of Pringsheim's theory of alternation.

His leading idea is that the successive generations among the
Thallophytes are to be sought in the free sexual and asexual
forms of the plant, and not in the plant itself on the one hand,
and its fruit on the other. To take only one example ; in the
case of the Floride.ie, Pringsheim regarded the tetrasporic and
the sexual individuals as constituting the alternate generations ;
the sexually produced crystocarp he interpreted, not as a dis-
tinct generation, but as a case of polyembryony. Having
expanded this view, he proceeds to face the difficulty, how it
is to be reconciled with the life-history of the Mosses (in the
widest sense), in which the alternation is between vegetative
plant and fruit.

His reply is very ingenious: in the germination of thesexually
produced spore of many Thallophytes the young plant sup-
presses more or less completely its vegetative stage, and pro-
ceeds at once to Ihe formation of asexual spores; this is the
case, for example, in CEdi^^oniityn^ SpfucropUa^ HydrodictyoUt
and more especially in the Phycomycetous Fungi, in which every
transition can be traced between " sporangial " and "mycelial
germination of the sexually produced spore. Pringsheim goes
on to say : " It may therefore hold good, as a general experience
among Thallophytes, that the firit neutral generation hurries
by a short road to spore-formanon. suppressing more or less
the vegetative part of the plant. ' This change is most marked
where germination takes place within the oogonium, as in
ColiocJurte. " .\lternation of generations in the Mosses thus
appears as a contracted form of that in Thallophytes ; in the
former the neutral generations are reduced to a single one, which
remains in unbroken connection with the sexual plant. There
is therefore no reason for comparing the sporogonium of a Moss
wiih the fruits of the Thallophytes," and so on.

On this view it follows that all alternation of generations
must be regarrled as " homologous. " Sporophyte and oophyte,
however differently modified, are homologous one with another,
both having been derived from sexual and asexual individuals,
which at one time presumably differed as little from each other
as do the cystocarpic and tetrasporic plants in Red Seaweeds.
It is therefore not surprising that in cases of apogamy and
apospory, the one generation may still pass over directly into
the other.

These views have been much criticised, and the case is still
sill' Jiidice. In England the opposite theory — that the alterna-
tion in the higher Cryptogams is " antithetic," the sporophyte
being an intercalated generation, not homologous with the
ocrphyte, is predominant, and appears to receive some support
from certain minute histological differences between the two
generations. Pringsheim's interpretation of the facts has, how-
ever, some advantages, perhaps the most conspicuous among
which is that it would enable us to understand the existence of
the immense and unbridged gulf which separates the sporophyte
of the Muscineae from that ol the Vascular Cryptogams. "The
latter might well have been derived from ancestors, in which
the " first neutral generation " had never suffered the extreme
reduction which characterise it in the Moss series, but h.id
always retained its vegetative organs. It would then no longer be
necessary to endeavour to force the plant of a Fern or a Horsetail
to fit into the Procrustean limits of a Moss-sporogonium.

We have endeavoured to give some idea of Pringsheim's
varied activity in the field of morphology, which he cultivated
with unsurpassed success. It remains to say a few words
regarding his physiological investigations, though these are far
from possessing the same importance.

So far as we have been able to find, Pringsheim's first entry
upon the physiological domain dates from the year 1S75, when
he published papers on the spectrum of chlorophyll, and on
the modifications of th.it pigment. His dclnif as a physiologist thus
almost exactly coincides with the climax of his brilliant career as
a morphologist. It was not till 1S79, however, that he became
prominent in physiological questions. In that year he produced
his first paper on the action of light and the function of
chlorophyll. He investigated the action of light of great in-
tensity on vegetable tissues, and observed the consequent de-
struction of the chloroph)ll, in green tissues, and the disorgan-
isation of the protoplasmic structures, both of which he attri-
buted to excessive oxidation.- The great conclusion at which
he arrived, is that " the function of chlorophyll, by means of

402

NATURE

[February 21, 1895

I

its powerful ab«)rptioa, especially of the so-cilled chemical
rays, is to limit the intensity of respiration, and to serve as a
rigulator of that process " He then proceeds further, and
states that " the fact that only green parts of plants evolve
oxygen, finds its sufficient explanation in the diminution of the
amoont of respiration, owing to the presence of the chlorophyll
screen." Pringsheim thus regarded assimilation as a function
of the protoplasm alone, with which the chlorophyll has
nothing to do, except in a purely nega'ive way, by keeping ofi'
rays which would induce the opposite process of oxidation.

In the same year, Pringsheim announced his discovery of a
body which he called Hypochlorin. This he was able to
demonstrate in the chlorophyll corpuscles by the aid of certain
reagents, notably dilute hydrochloric acid. lie regarded
hypochlorin as the first and most constant product of assimi-
lation.

Both of Pringsheim's conclusions were sharply attacked, and
an extensive controversial literature soon grew up. As regards
the hypochlorin, it seems certain that Pringsheim was mis-
taken in the impirlance he attributed to this body. It has
been clearly shown by Arthur Mayer, and others, that hypo-
chlorin is not a product of assimilation, but is derived from the
chlorophyll itself, by the action of the reagents employed.

The other theory, that of the screenaciion of chlorophyll,
has not met with much favour from physiologists, and it is clear
that this is, at any rate, not its only function. The inve-tiga-
tijns of TimlriazefT and Engelmann have proved that certain of
the rays absorbed by the chlorophyll (principally those in the
red) are just the rays mo5t active in the decomposition of carbon
dioxide. The chlorophyll, in fact, is not merely a screen, but
is also a light-trap, which catches and detains those rays which
are most effective in the assimilative work of the plasted. On
the other hand, recent investigations as 1 1 the action of light on
protoplasm have shown that many pigments (such as those of
spores and pollen-grains) are useful as screens, and have ren-
dered it probable that this may be a function (though not the
mist important one) of chlorophyll also. The discovery, by
Winogradsky, that certain Uicteria can assimilate carbon from
inorganic carbonates, without chlorophyll, and in the .absence of
light, is a striking confirmation of the view that the seat of
assimilation is the protoplasm itself, and to this extent Prings-
heim's opinion is completely justified.

It would be unfair to deny considerable credit to Pringsheim
for the boldness and originality of his physiological theories,
and the energy with which he supported them. Yet it must
be admitted that his views on these subjects were one-sided, and
not characterised by the same sober judgment which distin-
guishes his morphological researches. Entering, in mature life,
upon an unaccustomed field of investigatian, he failed to add
greatly to his previous reputation ; and though much of his
physiological work is suggestive, it has not given us, as he
intended it should, a consistent theory of assimilation.

Passing over some of the physiological papers of second-yy
importance, we come to Pringsheim's last work (l8S8), which

treats of i' • •■■■ 'f calcareous Incrustations on water-plants.

lie expl.i ess by the removal of carbon dioxide from

calcium !■ during assimilation, causing the precipita-

tion of the insoluble calcium carbonate. This theory is sup-
ported by the interesting observation that the incrustation only
takes place In the lii;Iii ; but it may be doubted whether the
explanation given is suliicient.

We have not attempted to record all Pringsheim's re-
■earches, but enough has perhaps been said to give some idea
of his life's work.

In addition to his original investigations, Pringsheim ren.
dered a great service to science by means of his magnificent
Year-book for Scientific Botany, which shares, with the botan-
ical portion of the I-'rcnch ./«;;.;/<•; iles Sciences Naturelles, the

honour of con- -..i. i, . . .-i — nrd of morphological

and physiolo; ry to hear that, since

the death of ; , jf litis great publica-

tion has been undertaken by two such distinguished botanists as
Profs. Slra»burgcr and I'frflrr.

By the death of l'rlng»lieim we have lost another of the
leaders who guided scientific botany through the period of its
n, growth. Very few of his grn'jration now remain ;

tl worthy successor* behind tlicm, l)ut the work of

1';. ..„ , in the field 'if m')r|iliolf.i;y, will not soon be

rivalled.

n. II. Scott.
NO. 132 I, VOL. 51]

THE ANTITOXIC SERUM TREATMENT OF

DIPHTHERlAy
'T'lIE subject with which we shall deal to-night, though at
first sight of interest to the phy-ician only, has been so
fully discussed in the public prims, and has been so bitterly
and irraiiorally opposed ontheonehand (pcihaps also unreason-
ably bcplauded on the othrr), that ihose who take even a
general interest in the public heaUh, or who ate wishful to obtain
some insight into the pracucal and scientific aspects of a new
system of treatment, may well be interested lo know something
of what is being so fieely discussed in the columns of our daily
newspapers. Beyond this, however, ni.iny lake a more personal
interest in a method of treatment which holds out promise of
help in the cure or amelioration of the symptoms and conditions
met with in diphtheiia. a disease which, very justly, Is looked
upon as one of the most dangerous with which the physician has
to deal. To begin with, I should like to make a frank con-
fession. With that conervatism which is met with even in
the most radical of natures, many, of whom I was one, felt
disposed to treat antitoxic scrum as belonging to the same group
of sulistances as tuberculin, around which was constnicted a
theory of which the labor.atory experimental basis, though ap-
parently fair and firm, was as yet insufficient for the support of
the structure of therapeutic treatment that was afterwards raised
upon It. 1 followed the earlier experiments on this new method
with great atiention ; I carefully analysed llie principles on
which the method was founded, and then with some misgivings
watched the gradual development of the treatment as applied
to ac ual cases of diphtheria. I was inclined to receive the
statistics with great reseive, as I felt that iliis new method, like
all new methods of treatment, might be making cures in the
minds of the obser\er, and not on the bodies of ihe patients.
Now, however, I am convinced that whatever justification my
incredulity may have had from the con-iderailim of previous
experiments, none could be claimed in connection with the
expc'lments that were carried out in the inves igation of this
sjiecial subject, .and I am ihoroughly satisfied that, although
the aniiioxic scrum treatment. may not come uplo the expecta-
tions of ail the r.ash writers on the subject — for many people
seem to think that it sho dd be a specific agamsi diphtheria in
all its stages — It promises, and this promise has in pait been
rdcemed, to dimmish the diphtheria case mortality in a very
remarkable manner.

What is Diphlheria ?
It is primnrilyan inflammation of the mucous membrane (the
moist skin) of the tonsils, of the soft p.ilaie, of the upper part
of the gullet, and of the upjier part of the windpipe. During
the course of this Inflammation, which appears to be set up by the
aciion of a special bacillgs. there are usually thrown out some of
the fluid elements of the blood and some of die white cells that
float in the blood ; these coagulate and lorm asoft lout;hish layer
or film which oflcrs an excellent food and resiing place for this
bacillus, which under such favourable conditions secreles or
manufactures a most virulent poison. This poison is rapidly
absorbed into the blood and is carried to various parts of the
bDdy ; its effects are evident at first only os the nervous
system, but afterwards on the muscles.

The liacilius of J diphlheria.
First as to the bacdlus. In 1875 Klebs described a short
bacillus which he found on Ihe suilace of the greyish leather-
like diphtheriuc false membrane or film. Following up these
observations, I.oefller traced a definite etiological lelatlon-
shlp between this bacillus and diph herla. First he obtained
pure cultures of the bacillus by growing it on .solidified
blood scrum, or on a mixture of three pans of blood sciuni and
one part of neutralised beef bouillon coii aining cxiraci of beef,
I per cent, of peptone, 05 per ccni. ol common salt, and 1 per
cent, of grape sugar. This organism may be readily detached
from the surface of the false membrane by pressing
fiimly but gently with a liille bit of cotton wadding twisted
round the end o( an iron wire or nn ordinary penholder.
When stained and examined under the mi roscnpe Ihe
diphtheria bacilli arc fout.d 10 be .small rods liom 3 to 6 ^ (i m
= ..:,.'. ,...'h of an inch) inlergih, fairly plun p, siiaighi, i>r slightly
curved, i-oii etimcs wedgc-sha]ie<l or poinerl, but usually some-
what enlarged and rounded at the ends, where also in stained

1 A lerlurc .delivered al the Royal Intlilulion, on Friday. February 8,
by Dr. G. .Sinn Woodhead.

February 21, 1895]

NATURE

403

specimens the protoplasm is more deeply tinted than in the
centre. This organism grows singly or in groups, or felted to-
gether to (orm a net-work ; it may occur in irregular masses of
considerable size. When these hacilli have been growing (or some
time on an artificial nutrient medium, they appear to be segmented,
the stained materiil accumulating in small round nodultrs placed
at intervals wiihin a kind of membrane which is only very deli-
cately tinted. During the past five weeks I have examined about
600 specimens taken from the throats of diphtheria patients, and
I may say that in nearly every case where the disease has been
diagnosed by the physician in chnrire, as being one of diph-
theria, these typical bacilli have been found, whilst in those cases
in which there was any doubt as to the nature of the disease,
similar bacilli wf re found in some, but not in oihers.

This is of importance, because we shall find that this bacillus
gives us the sulistance with which animals are rendered immune
to the attacks of the bacillus itself, these immune animals in
turn supplying the anti'oxic serum. To prove that this bacillus is
really the cause of the disease, Loeltler, in an elaborate series of
expeiiment";, inoculated the pure cultures of the bacillus grown
on artificially prepared media, into animals ; he was thus able
to set up characteristic lesions, especially if he took the pre-
liminary precaution to abrade slighily the mucous membrane,
thus as it were ploughing the ground before scattering the seed.
On such abraded surfaces llie bacilli grew very luxuriantly, and
false membranes were produced ; in these lesions the hacilli could
afterwards he found and again separated in pure cultures, whilst
the characteristic toxic symptoms of diphtheria weie in each case
experimented upon, repeated with the utmost fidelity. Loeltler
also pointed out a mo>t important lact in conneciion with the
presence of the organism in the body. He found that it was
strictly confined to ihe local wounds or lesions in the ihroatand
posterior part of the nose, and he was also able to prove that in
this position these organisms commenced to manufacture most
virulent poisons, which, unlike the bacilli, can become difiused
throughout the body. Klein and Sydney Martin in this country
have boih made very valuable contributions to our knowledge,
the former concerning the bacteriology of the disease, the latter
in regard to the chemical action on the tissues of the toxic or
poisonous products of the bacillus.

The To.xiiics of Dipiitheria.

Martin found that after the poison formed in the throat has
made its way into the internal organs of the body it undergoes
certain changes ; it is broken down into somewhat less poisonous
compounds, but these, accumulating at certain points, act especi-
ally on the nerves and muscles. It appears then that we have to
deal with two sets of poisons : a very virulent poison formed by
the bacilli directly from the fibrin and albuminoids of the fiuids of
the blood, exuded on the surface of the mucous membrane ; and
secondly, a less poisonous series which appear to accumulate
especially in Ihe spleen. So long as these poisons remain in
the body we have the general fever, rise of temperature, and
altered conditions of circulation (as evidenced by the pulse), so
characteristic of the disease. At a later stage, sometimes after all
the primary symptoms of diphtheria have p.assed away, there
are often met with what are called post-diphiheriiic paralyses,
which are due apparently to alierations in the nerves going to
muscles, especially those going to the delicate muscles of the soft
palate and around the opening into Ihe windpipe, though other
groups of nerves and muscles may be similarly affected. These
post-diphiheriiic paralyses may be due then to the action either
of the virulent poison (ferment) formed in the membrane, or of
the .somewhat less puisonous but more stable toxines that are
formed in the later stages of the disease. Through the kind-
ness of Dr. Martin I am enabled to show you figures of nerves
and muscles, the degeneration of which is due to the action of
these poisonous substances. It is here unnecessary to enter
into any detail as to the minute changes that take place in the
nerve and muscle fibres, but on comparison of the aflected
nerve fibres with a healthy nerve fibre, it is evident ihat we have
here grave struciural alterations which must interfere most ma-
terially with the pciwer of the nerve to conduct nerve impres-
sions from the spinal cord to the muscle. The outer part orsheaih
of the neive is in some places entirely wanting, whilst in other
cases the axis cylinder or core of the nerve is either greatly at-
tenuated or entirely absent. The prison in these cases has set up
changes by which the communicating paihs between the muscles
and the spinal cord and brain have become ihoroughly dis- I
organised. The muscles, too, instead of being formed of cleanly

NO. 132 I, VOL. 5 l]

striated fibres, have this striation greatly obscured, first by a kind
of cloudy or ground-glass look, and later by the appearance of
a number of -trongly refractilc granules. These, when stained
with osmic acid, become black, from which we argue that they
are composed of fat, and it is said that the muscle has under-
gone a fatty degenerttion, the muscuUr protoplasm being
partially converted into fat ; nbimately the striatinn may
be almost lost. In a case of diphtheria, then, the following
stages may be traced: a sore throat (often simple enough
to begin with), by which the mucous membrane is prepared for
the receptii II of the diphtheria bacillus. The diphtheria bacillus
becomes implanted on this surface, gives rise to an acute in-
liammatory condition, and, subsisting on the inflammatory
exuHalion, sets up a local manufactory of a most virulent poison.
This poison, absorbed into the circulation, at once acts on the
nervous system, although a certa'n proponion seems to be
broken down into more stable, but less virulent, poison, which
remains in the body, and may continue to act for a considerable
time on the nerves and muscles.

Immunity against Diphtheria.

Whilst these poisons are attacking the more highly
organised, and therefore less stable tissues, they are stir-
ring up or stimulating the other tissues of the body to resist
their invasion and action. If tnis were not the case,
any one attacked by diphtheria must eventually succumb
to the disease ; but we know a considerable proportion of
the cases of diphtheria recover even when no treatment at all
is resoried to. Whatever may be the exact explanation of this
recovery, we know that it depends upon the power of certain
cells in the body to accommodate them-elves to the presence of
' the toxines, and to go on doing their work of scavengering and
of removing foreign substances from the body even under what
originally were adverse condition-. ; during this process the cells
become so profoundly and permanently altered that the patient
is for some time protected against further attacks of the same
disease. It was originally maintained that this alter-
ation was entirely conlined to the cells, but it is now gener-
ally accepud that these cells form or secrete substances which,
thrown into ihe blood, either act direcily upon the toxines so as
to interfere with their activity, or so react upon the cells that
they are able to coniinue their work in the presence of the
toxine. At all events, a certain immunity against the disease is
acquired. Upon these various theories is based the rationale of
the antitoxic serum treatment of diphtheria. Ferran claims to
have been the first to obtain such a condition of immunity
against diphtheria in animals: shortly afterwards, Fr.aenkel
in Germany obtained similar results. Seeing that this
immunity depends upon an alteration in the composition
of the serum, should it not be possible, argued Prof. Eehring,
to take the serum of an immunised animal and transfer
it to a patient suffering from diphtheria, so as to help the
tissues and cells of the patient to cope with the toxic products
of the diphtheria bacillus during the earlier stages of the dis-
ease, inducing, .as it were, a kind of artificial immunity to help
the patient over the acute period of the attack when the poisons,
though most virulent, are most unstable, and when the tissues
have not yet become ;icclimatised to the presence of the toxic
products of the bacillus ; when, in fact, they are paralysed and
are able to do little to protei t themselves. Behring so followed
up this idea, that he was able to initiate a system of treatment
which promises to revolutionise our therapeutic methods in the
treatment of certain specific infective diseases.

I'hc Production of Antitoxic Serum.
Workingon the fact that an animal might be rendered more and
more insusceptible to the action of the toxic products of bacteria,
Behring found that he might proceed in either of two ways.
He mi^'ht make an artificial wound with a nee ilc, anil introduce
weakened bacilli into the animal, the weakened bacilli then
growing but feebly and producing a modified toxine. After
the effects of ihe first dose h.id passed otT, he was enabled to
increase the dose and to use more active bacilli, injecting them
first into the tissues and eventually directly into the circulation,
with the result that enormous doses of virulent diphtheria bacilli
might ultimately be introduced without giving rise to more
local swelling or general febrile disturb.ince than was first
noticed when the small dose of modified bacilli was introduced.
Such a method as this, however, was attended with con-
siderable drawb.acks, as it was almost impossible to gauge, at

401

NA TURE

[February 21, 1S95

all accurately, the number and strength of the bacilli. Not so.
however, with the product? of the micro-organisms, the activity
of which could of course be more accurately measured, and the
do<e more accurately graduated. The bacilli might multiply
and continue their action on the tissues, but the poisons when
injected alone would not alter in quantity or activity. As may
be readily imagined, the fluid constituents of the blood can
only contain tho-e substances that are introduced into it from
without, either through the vital activity of the cells of the
body, the products of which must be thrown into this fluid
before they can be excreted, or through artificial injection. The
antitoxic substances then found in the blood of an immunised
.laimal, must in the case of natural immunity following an attack
of diphtheria be the result of the activity of the tissue cells,
especially of the connective tissue and white blood cell groups
which have been "stimulated " by the toxines introduced from
without, from the false membrance in the throat. Where it is
desired to produce an artificial immunity, and an "artificial"
antitoxic serum, the cells are stimulated by the introduci ion into
the body of ariificially prepared toxine. The cells acted upon
by the toxine elaborate ihe protective fluid, which is thrown into
and accumulates in the blood. This substance may act in one of
several, or even in several ways. (|> It may directly antagonise
the diphtheria toxine, and may thus prevent the paralysing
action of these poisons on thescavangering cells or phagocyles.as
they are called ; these, left free to perform their proper functions,
can deal with the foreign elements that have got into the blood,
and also with the bacilli at the seat of the local attack, for, as has
been pointed out by several foreign observers, and by Ruffer in
this countiy, immediately beneath the layer of bacilli in the
false membrane there is usually a very considerable accumula-
tion of leucocytes, especially in those cases in which recovery
ultimately takes place. (2) The antitoxic sub-tances may act on
the bacilli, inhibiting their growth and interfering with their
power of producing toxines. This of course can only be a local
action should it play any part in ;he process. (3) These sub-
stances may act directly on the cells of the blood lymph
and tissues, so stimulating and strengthening them that
they are able to perform those functions above mentioned.
It is at present difficult to state which of these pro-
cesses is the one, or the most important, in protecting or
curing the patient, and it may be that all play a part. It may
be that the tissue cells, when acted upon by the specific
diphtheria poison, become so modified that they are enabled to
produce or secrete a sulistance which directly antagonises the
action of that poison. This substance, thrown into the blood,
remains there for some lime, rapidly accumulates as larger and
larger doses of the poi-on are thrown in, neutralising the poison,
whose power of doing damage to the tissues is thus held in
check, but remaining (or some time after the toxine has disap-
peared ; or thi^ autitoxic substance, reacting upon the cells,
may render them Ic-s susceptible to the action of the toxine.

The earlier immunising experiments were naturally performed
upon the smaller animals, such as rabbits. Then lichring used
sheep, and after various other animals h.nl been tried, the horse
was selected by Roux and Nocaid as perhaps the best of all
animals from which to obtain antitoxic serum. In the first
place, be is comparatively insusceptible to the action of the
diphtheria bacillus— even considerable doses of living bacilli
may be injected under the skin without producing anything
more than a slight local. swelling and a rise of temperature.
It ha» also been found that horse serum, when injected,
produces little or no change in the healthy human sub-
ject— that is, the -trum seems to mix ptrfectly well with
human blood plasma, and there is comparatively little danger
of the extra serunti being excreted by the kidneys in the form of
albumen. This is a most important point, and one that no
doubt influenced Koux and Nocard in their selection of the
horse a.* an animal from which to obtain immunised scrum.
beyond this, however, the blood, (when drawn from the vessels,
separate' very perfectly into two porliuns— a firm clot, which if
the blood be caught in a cylindrical gla.s jar. forms a kind of
column in the centre, anri a clear slian.colNured scrum which
accumulates around the clot, and lorms a layer often several
inches deep alrave it. This serum contains the antitoxic sub-
stances. Lastly, considerable <|uantitits of blood can be
obtained from such a large animal n.s the liorse, and if he be
well fed, grr>omcd and exercised, the process 01 bleeding may
be repeated pretty frcrjuenlly without causing any inconvenience
10 the animal ; in fact, as one observer said, he stands bleeding

NO. I32I, VOL. 51]

as well as did our forefathers, who thought as little of being bled
as we think of going to Aix or liuxton.

Let us now turn for a moment to the method of treating the
horses that we wish to render immune, in order that they may
supply the antitoxic scrum that is to be used for the treatment
of cases 01 diphtheria. Roux's method, which is that that h.is
been most carefully described, and which is the one used in
this country first by Dr. Ruffer at the liritish Institute of Pre-
ventive Medicine, and then by Prof McFadyean at the Royal
Veterinary College, consists in introducing diphtheria toxine of
a given strength in gradually increasing doses, until the blood
of the animal so infected is found to contain a sufficient quantity
of the antitjxine.

Preparation of Diphtheria Toxine.

The toxine with which the animal is to be injected is prepared
as follows : — A broth is piepaied by soaking a pound of finely-
minced beef in water. This is allowed to stand for twenty four
hours in the cold. To the fluid expressed from tlie meat fibre
at the end of that time is added A per cent, of common sail
and 2 per cent, of peptone (meat artificially digested by pcpsine).
This broth is then rendered faintly alkaline by ihe addition of
soda salts or caustic soda. This is done because it is found
that the diphtheria bacillus cannot grow at all vigorously,
or form its poisons rapidly in an acid solution, and such
poison as is formed is neutralised, or is unable to act
in the presence of even a faint trace of acid. It is found
that even in Koux's solution, which is always faintly alkaline
to begin with, an acid reaction soon appears, but, after
about ten days, this is replaced by an alkaline reaction, and .is
soon as this takes place, the growth of the bacilli takes on new
activity, the quantity of toxine is increased, and it becomes
much more virulent. Roux found that he obtained his most
virulent toxines after a month's growth. If the growth is
allowed to go on longer than this, a process of oxidation appears
to take pl.ice, and I have found that the toxine from a culture
carried on for two months had already lost much of its toxic
activity. It should be noted that a virulent bacillus should
always be taken in the first instance, otherwise the results may
be very disappointing.

This nutrient material is placed in a layer of not more than
half an inch thick in a flat-bottomed flask, which is plugged
with cotton wadding, and then closed with an indiarubber cork
or cap. Through this composite plug three tubes are passed
into the flask ; the two lateral tubes are bent at right angles,
both inside and outside the flask ; whilst the centre tube
is fitted with a small thistle-head, which may be plugged
with cotton wadding, and then closed with an indiarubber
cap. The outlets of the lateral lubes ire also plugged
with cotton wadding, and the whole apparatus is kept for
an hour or two in steam maintained at a temperature of 100°
C. (flasks so treated may be preserved for years without any
change, beyond some slight evaporation, taking place in the
broth.) A small quantity of a pure broth culture of the virulent
diphtheria bacillus is now drawn into a long thin pipette, the
indiarubber cap and the cotton wadding plug are removed from
the thistle-head, and the contents of the pipette arcintroduced ;
the pipcite is withdrawn, the cotton wadding is replaced, the
indiarubber cap is fitted in jiosition, and the flask is placed in
an incul:)ator which is maintained at the temperature of the body
igSV J'-' <^' 3S"'2' C). As soon as the grosvth is well started
(usually at the end of aliout twenty-four hours), a current of moist
air is made to pass continuously over thcsui face of this cultivating
fluid, the air being first warmed and saturated with moisture, in
order as far as possible to prevent evaporation. A fine flocculent
deposit soon makes its appearance on the bottom of the vessel,
the supernatant fluid remaining clear. This deposit increases in
thickness, much moie luxuriant growth going on alter the first
ten days. Toxine is formed by the diphtheria bacilli so long as
they can grow freely — that is, so long as they can obtiiii sufli-
cient nutrient material from the fluid and Irom the air that is
continually passing over the surface. At the end of a month,
if all these precautions are taken, the toxine should be of such a
strength that i/iolh of a c.c. (about two or three ilrops) injected
into a guinea-pig weighing 500 grammes (over 17 ounces) will
kill it within forty-right hours. The strength of the toxine or
poi.son may be a little greater or a little less than this, but it is
a compaiaiively e.asy matter to measure the strength, and there-
fore to graduate the dose to be used in immunising the horse.
This only holds good, however, if the active diphtheria b.icilli

February 21, 1895J

NATURE

405

are removed or destroyed ; the^e, if left in the fluid, would be a
complicating and inconstant factor in the equation. In order to
kill these bacilli the Germans recommend the addition of \ per
cent, of carbolic acid to the cultiirL- ; the dead bacilli fading
to the bottom, leave a perfectly clear supernatant fluid. The
French, on the other hand, recommend the separation
of the bacilli from the fluid by means of a Pasieur-
Chamberland filter. By this means a clear virulent poison
which does not contain any diphtheria bacilli is obtained.
With this fluid a horse with a good constitution, and
which has been proved to be free from tubercle and
glanders, is injected under the skin of the side of the neck in
front of the shoulder. Small doses are first injected, either
pure or with the addition of i '3 of the volume of weak solu-
tion of iodine of potassium. II the fluid is of full strenjjth, only
about 2C. c. can be given at the first injection. This is followed
within twenty-four hours by a local swelling at the seat of in-
jection, about the size of the palm of the hand, and the temper-
ature may rise l°or2' F. (.i°to i' C), otherwise the general health
of the horse does not seem to suffer. He eats well, and unless
regularly exercised may become very lively; of this we have
had ample evidence during the recent frost and snow, when it
has been unsafe to give much exercise to horses that are not
very sound in limb, and as a result Ihey have been very fresh
indeed. As soon as the swelling has disappeared and the
temperature has receded to the original level, a somewhat larger
dose is given ; the same process is repealed time after time (the
dose being gradually increased to bring about the same amount
of swelling and lise of temperature) for about three months, or
until such lime as the requisite amount of immunity is acquired,
i.e. until the antitoxic action of the blood is sufficiently marked.
That there is a gradually increasing immunity is evidenced by the
fact that enormously large doses of the toxine in the later stages
of the treatment produce even less local and constitutional dis-
turbance than was observed after Ihe first few injections of
comparatively small quantities.

The blood is now drawn off' from the jugular vein of the
immunised horse by means of a metal cannula or tube to which
is attached an indiarubber tube ; these are first thoroughly
boiled, in order that no living micro-organisms of any kind may
remain on or in them, and ihe skin of the horse is carefully
cleansed with antiseptic lotions. The indiarubber tube leads
the blood into a flask or vessel which has also been carefully
sterilised, and provided with a well-fitting cotton-wadding plug
or glass-stopper. The vessel when filled is placed in an ice-
safe until the solid part, llie clot, is completely separated from
Ihe fluid— the serum. From each gallon of blood about one
quart of serum is expressed, thjugh this varies considerably in
different cases, and according to the time that the separation is
allowed to continue (24 to 48 hours). This serum, a limpid
straw-coloured fluid, is carefully decanted under strict antiseptic
precautions, and, mixed with carbolic acid or camphor, is
stored in small phials, each of which contains about a sufficient
quantity for the treatment of a single patient. In the Pasteur
Institute, and in the Uritish Institute of Preventive Medicine,
the antitoxic serum is apparently brought up to such a strength
that , i,r of a c.c. injected into a medium-sized guinea-pig (500
grammes, or over 17 ounces) will protect it against an injection
twenty-four hours later of \ c.c. ot a culture of living
diphtheria bacilli strong enough, if given by itself, to kill the
guinea-pig in twenty-four hours. It is usually recommended
that 20 c.c. of this serum should be given at ihe first dose, and
that if necessary a second 10 c.c. should be given half an hour
later. The method of testing the strength ol the setum .adopted
by the Germans is that devised by Ehrlich, who takes ten
limes the lethal dose of diphtheria loxine, and in a test-tube
adds a definite and known quantity of the blood to be tested.
This mixture is then injected into a guinea-pig, and if the anti-
toxic power of the blood has been gauged aright, the animal
does not suffer in the slightest degree from what under ordinary
circumstances would kill ten guinea-pigs. The addition of less
or weaker serum, or of more toxine would leave the mixture
still toxic.

In order to obtain a definite standard with which to compare
the antitoxic power of any serum, and to determine the dose of
such serum, Behring and Ehrlich have described what they
term a normal antitoxic serum — that is, a serum of such a
strength thai ,',,ih of a c.c. added to ten times the lethal dose of
diphtheria toxine isexactlysufficient to render it innocuous. I c.c.
of such normal serum contains one "immunisation unit," and

should be sufficient, when added to a hundred times the lethal
dose and injected, to render it innocuous. In horses wholly
immunised the serum may be hfty or even a hundred times as
active as the normal serum above mentioned and the dose
to be given varies according to the number of immunisation
units in any sample. It is not here necessary to go into the
j question of do>e, but it may be staled that 500 of these
! immunisation units are usually necessary to produce the desired
j effects in cases of diphtheria, though in some cases still larger
quantities have to be used. Behring now supplies four strengths
of the serum, the weakest (marked with a yellow label) is sent
out for injection of cases where the disease has not already
been contracted. The next (marked with a green labelj is of a
strength of 600 antitoxine units, and is given to those cases in
which the treatment is commenced at the very outset of the
disease— that is, when the firstsymptomsof diphtheria manifest
themselves. The next stronger antitoxic serum (white label)
equals 1000 antiioxine units, and is used fcr cases somewhat mere
advanced in which the prognosis is at all grave : whilst in still
j graver cases, and where the symptoms have been developed for
some considerable lime, it is often necessary to give a serum of
1500 units ; ihis is marked with a red label, and is of course
highly concentrated in order that the size of Ihe dose may not
be unduly increased. In place of No. i. healthy children and
adults who are exposed to diphiheritic infection mav receive a
quarter of the dose of the gieen label flask, which Behring
considerswillprotect against diphtheria with verygreat certainty.
Although the>e general directions are laid down, it is strongly
insisted upon by Behring, Kossel, Roux, and in fact by all
those who have had experience of antitoxic serum, that the dose
must vary according to ihe severity of the di;ease, so that much
must be left to the discretion of the medical practitioner in
charge of the patient. The great error into which those who
first me ibis agent fall, is the administration of far loo small a
dose, especially in the case of children, for whom ihe dose is
nearly as large as it is for adults. For this reason some of the
statistics published in this country and abroad are far too
unfavouiable to the method. The great drawback with this
method is that the dose necessary to be injected is so large ;
but in the loose tissue of the side of the chest, the back, or the
buttock, immediately under the skin, the fluid soon disappears.
It is hoped that before long, however, the active principle may
be separated, and so obtained in smaller bulk.

So far we have dealt principally with the antitoxic serum as
prepared by Behring and Roux and by Roux's method, which
is certainly attended with comparatively few difficulties ; these,
however, have the disadvantage that they take from three to six
months to give the desired results. In order to do away with
this disadvantage, Klein has carried out a series of experiments in
which he has been able to obtain serum of considerable activity
in as short a period as twenty-three days. Instead of introduc-
ing the poison only, he adopts the plan used by Behring and
Roux in their earlier experiments, of injecting living bacilli
which have lost a certain degree of their activity, using for Ibis
purpose old cultures. He afterwards introduces toxine along
with more virulent bacilli, and thus obtains in the animal such
a degree of immunity ihat it is enabled to wilhsland or to react
very slightly to moie than a fatal dose of diphtheria bacilli. By
the third week the animal will bear the injection of large
quantities of virulent bacilli, and by the end of twenty-three or
twenty-six days the serum has acquired such antitoxic proper-
lies that I c.c. of it will protect 40 to So guinea-pigs against a
lethal dose of living diphtheria bacilli. It is difficult to com-
pare these results with Roux's and Behring's, but Klein's serum
has been used with marked success in certain cases of diph-
theria. It appears to have a special power of causing the
membrane to clear away, and so to remove ihe manufactory of
the poison, as on this membrane the diphtheria bacilli accumu-
late. This method is mentioned as one that m.iy be used
especially where it is desired to obtain antitoxic seium quickly.
Smyrnow has suggested quite a diflTerent method of preparing
antitoxine. Under Nercki's advice he passed electric currents
through ihe seium of animals, and was thus able to endow it
with a certain immunising power. But he was still more
successful in obtaining powerful aniitoxire by electrolysing
diphlheiia bouillon cultures ; curiously enough, the more virulent
the culture the more powerlul was the antitoxic substance he
obtained. When this antitoxic substance was injected into a
rabbit, which Uvenly-four. hours before had received about
\ c.c. of a two or three days old diphtheria bouillon culture, there

NO.

1321, VOL. 51]

400

NATURE

[February 21, 1895

WIS a rapid rise of temperature followed by marked improve-
ment in the condition of the animal. This observer believes
that antiioxinecan he obtained by this method that will be much
more suitable for the treatment of the hum\n subject than tho^e
obtained byihe ordinary methods. His experiments, however,
are far too few to carry any great weight, though they open up a
mi's: interesting 6eld for future investigation.

( To be continut:1. )

uMVERSITV AND EDUCATIONAL
INTELLIGENCE.

Cambridge. — The extension of the buildings of the Caven-
dish l.ai'oia'oiy is about to be undertaken, at an expense of
over /'4000. About half the cost will be met from the accu-
mulated Ires of student^ working in the la'>oratory.

Nfr. E. Hamilton .-Vcton, Fellow and Lecturer in Chemistry
of St. John's College, died sudJenly, from heart di<ease, on
Friday niiiht. Mr. Acton was only in his thiriy-third yeir ;
but he had eamrd a considerable reputation as a chemist, and
his researches in vegetable chemistry, in particular, were of im-
portance He was an al>le and successt'ul teacher. His'uneral
on Tuesday was attended by some hundreds of the junior
mcmt>er4 < f the University, and by representatives of all the
sciemific departments.

Mr. Robert Perkins, of Je'us College, Oxford, leaves
England next week for Honolulu to resume his investigations
on behalf of the Joint Commitiee appoimed by ihe Royal
Socie'y and the Bti i*h Association for the zoological explora-
tion 111 the Sandwich Islands. The large collections he male
there during his former stay (March 1892 to September 1894)
have I een submiiieH 10 various -pecialists, wi'h results that show
him to be an indefatigable observer in all branches of terrestrial
zoolo^v ; and, since his return 10 England last autumn, he has
been busily engag-d in discovering what has yet to be done to
complete our knowledge of the indigenous Fauna which is so
rapidly disa|>pearing.

The County Councils of Northumberland and Durham are
truly advancng technical education by alTording as-i-iiance to
Dr. \V. Somerville, Professor of Agriculture in the Darhim
Collfge ol Science, to carry out extensive manurial trials. The
experiments were begun in 1892, on nine farms in Northumber-
land ; in 1S93, when Durham joined in the work, the number
of fa'm^ rose to t*eniysix ; while nuring 1894, ihe trials xere
made at no le-s than (orty-ihree difT-rent centres in the two
counties. The investiijati >ns mu-'t have a nit inconsiderable
influence np<in ihe prosperity of the agriculture of the district
to which they refer.

The Technical Instruction Committee of Ihe Essex Cnunty
Cotini il, wi h a view to promoting the sp end of scieniitic know-
ledge amrngihose engaged on the coast in ihc iishing indisries,
started a m-tiie-t hitilo^^ic »1 station at Bright I mgsea last year, anil,
nnderihesuprrinicndenceol Mr. J. T. Cunningham, a numbei of
spec mens were c- 'I lei ted for the pur poses of demon si rat ion. Some
exprrimenis 1 n the coniinemal method of growing oysiers were
tlv> commtnced but, owing to ihe unfav lurahle character of
the >eason, tte p suits could not be carried very far. We are
glad I" learn, however, that tl e Comnii irc, in conjunction wi h
the BiiMiii>h Ci ui cil o' Colchesier, propose 10 cary on ihc
work of ihesialion, and that ihe Fishmongers' Company hive
aI»o 9ho«n ti eir apprecn'tmn of the movement by giving a
grani ol £^0 per annum for three years.

The Manihesler Town Council have accepted a tender for
Ihe (Fiction ol a lechnical schiol at a cost ol £mo,ocx>.

SCIENTIFIC SERIALS.

Amtriian yournal of Afailifmnlui, vol. xvii. No. i. (January,
1895).— bar line iransfo'maiion de mouvcments, P. Ap|>ell, is a
treatment of Elliot's problem {Comfit! niidus, 18^3), and of a
qiiesiion fjl'cd by Mc»ischenky, in the Kiilleiin Jet Sciences
Malti. 1K94, Ks a pariic'lar < a.e of Ir msforination • f move-
ments.— An eitract from a letter arldrc-scd 10 I 'r. Craig by
M. He mile, gives the result of an in-e-lgati n of the
aiymploiic value ol log r(a) when a is arge. — On the fi'sl and
second Inganthmic derivatives of hvpcrclliptic « function , by
Oikar Doiza, ojicns with a statement of certain well known I

NO. 1321, VOL. 5 1]

theorems of the theory of elliptic functions and then extends
these and some a'lied theorems to liypereloptic funaions. — Sur
la de6nition de la limi.e d'une lonction. Exercice de logique
maihematiqiie, by Prof. Pcano. Ihe definition is one
previously used I y the writer, and also by two or three previous
writers. It is practically given by Al>el {IVoris ii. p. 199), in
the form. "Pour qu'une st'rie 2«„ soit convergente. il faut
que la plus petite dei limites de /;«„ soit zero." The 'ame
gei eral idea of a limit is given in Cauchy's "Cours
d'Analyse algebrique " (1821, p. 13), "quelquefois . . . une
expre sion converge a-I.a-fos ver- plnsieurs limites differentes les
unes ne« autres." Prif. Peano works on this (definition, and
demon-trates at <ome length its principal properties. To this
end he cmi<lo«s la log que mithematique, " Cette science s'est
rapi'ement deve'oppce rie nos jours, et on la appliquee dans
plu-ieurs travaux." — Dr. E. McClmtock contributes an article
on ttieoieiis in the calculus of enlirgement (a paper read
be'ore the Amer'can Mat^iematical Society, -August 14, 1S94).
It is an iniere-tiiig sequel to his essav on the calculus of en-
largement (vol. ii. pp. 101-161). — In his note on Foucault's
pendulum, Mr. Ch'ssm considers the motion of a physical
pendulum on the surface of the earth, taking into account the
rotation of the eanh about its axis. The init al velocity
relativelv to the eaith of the pendulum is supposed equal to
zero, as in Fiucauli's experiment. Hence he leta ns the name
of *' Foucault's pendulum," although oscillations of any finite
amplitude are considered. The p irtrait which is given with
this nuiiiber is that of M. E. Picard.

ll'ieifeiiiiiin's Antialen der Phynk und Chemic, No. 2. —
Fluorescence of solutions, by O. Knoblauch. There is a con-
stant r.Tti I between the in ensity of the flu irrsience and the
existing light, t ven uhen the intensity of the latter is altered in
the ra io ol I to 6400. The author proves exp nmenially and
theaelicallv that ihe effect upon ihe various fluorescent bodies
of virying the solvent is very dilTerent.- — The potential gradient
in the positive portion of the glow discharge, by A. Ilerz.
The poteniial gradient in the prsiiive unsiratifi d glow dis-
charge of a v.icuum tube decreases as the currem increases, and
also as the diameter ol the tube is incicased ; but it increases
»iih Ihe pns-urc, ihounh nnt as npidlv — Unip'l.ir induction,
by Ernst Leclur. The author discusses the difleient aspects
of the qutstion whether, when a cylindrical magnet rotates
ab ut its axis, the lines o' force due to ii are siationary, or
totiiewih ihe magnet. The former «as Karaday's original
view, tlie la'ter has been maintained by Tolvrr Pie-ton and
otheis. Afttr showing that all the experiments hiihertn quoted
as rie- isive one w ay or the other may be equally well interpreted
on eiiher assump ion, he describes s me test experimcn s which
show Ilia' he lines of foice stand still \vh le l^e magnet lotates. —
Electric dispersion, by P. Drude. A nt'^thol is desiiibed for
inves igating ihe iclaii. n betwien th- di lect ic cons'ant of a
substance and the period if the el' ciric waves triversing it, or
what mayb- described as the electric dispersion of the sub-
sUncc. If the oirltclric constant deciencs as the period
increase, th' re will be normal, if it incr ases, anomalous
dispersi n. F'"«r al ohol the d spersion was found to lenormal,
anil of ihe s'.me ordi r of mi'gnitiide as its optical r'i^persion.
Water sI'O • ed abnormal diS|erion with he la'ge wave-lengths
U'C I, whereas e onite showed no pc ceptible dispersion. —
Ellect o ka'iiode rays upon some sa't-, by E. Goldstein.
Litliinm c'llor de, «hen exposed m Kithode rais, assumes a
h lioirope "f durk vio'ei ci loui, which it retain- lor siine time
in a se led tul'C, I hi rides and o lie h.'loii S'lts ol potassium
and oiiiiim show simi ar efiects. The colours are vciy super-
ficial, and di.-appcar on heating, or by the action of moisture.

SOCIETIES AND ACADEMIES.

London

Geological Society, January 23. — Or. Henry Woodward,
F.K.S., I'ns'ileni, in the chair. —Carrock Fed : a study in the
vaiiaiiou of Igneous rock-mosses. Pari li. The Carrock Fell
Gr..niiphyie. Pait iii. The tirairsj^dl Grei-en, by Allrcd
lliik-r. The augite-granophyre ol Carmck Fell was first
decnbcd in iis noimal devc opmei.t, special ailtnion being
drawn 10 the various lypcs of micmgiopiiic intergiowths which
It exhibits. The variation of the roik was next examined,

February 21, 1S95J

NA TURE

407

and, in particular, a curious basic moriification which occurs
near iis junction with the gabbro described in a former paper.
The granophyre here passes into a coarse type rich in augite,
iron ores, and apatite, its silica-percentage falling to as low as
58. The author attributed this to the acid magma having
incorporated in iiself portion-- of the highly basic margin of
the gabbro. The latter rocl< seems to have been fu^ed or '
dissolved by the magma, with the exception of certain of its
more refractory minerals which survive in the modified
marginal part of the granophyre. The latter part of the paper
ilealt with a remarkable quartz-mica rock found on the north
side of the Skiddaw granite. Ii differs in some r< spects from the
Cornish grcisens, and rtsembles in is mode of occurrence
certain pegm.atites in the Scottish Highland-. The author
considered the rock to have been extruded from the granite
in connection with the post-.Silurian crust-movements of the
district, while iis compr-ilion has probably been further
modified by subsequent chemical change'. — The geology of the
country abound Fishguard (Pembrokeshire), by F. R. Cowjier
Reed. — The tract of country forming the subject of this
communication occupies the nonhun part of Pembrokeshire,
from Newport to Sirumble Head. — On the mean radial
variation of the glube, by J. Logan Lobley. The author
submitted considerations (chiefly derived from the characters
of the earlier sediments) which led him to suppose that crust-
folds have not been produced by continuous contraction of the
earth, and ihat the planetary heat and mean radius of the earth
have been pr.aciically invariable during the period which has
elapsed since Cambrian times.

Zoological Society, February 5. — Sir W. H. F'ower,
K.C H., F.R.S., President, in he chair. — A communication
w.as read from Dr. E. A- Goeldi, in which lie described the
breeding haliits of some trce-fro^5 ob-erved by him in the
Province Rio Janeiro. J/yla fub^r, Wied, constructs nests of
mud on the shallow borders ol p mds, wherein the young are
protected from enemies whilst in the larval s'ate. Hyla gceldn^
Boulenger, dispenses with the metamorphose?, whtch are
hurried through within the egg', these being carried by the
female on her back. Hyla nchuloia, Spix, depo-^its its eggs in
a slimy ma-s attached to withered banana. leaves, the young
remaining in this soit of nest until in the perfect, air-breathing
condition. — Mr. Eilgar A. Smith gave an account of a col-
lection of anl-shelU made principally by Mr. A. Everett at
Sarawak, liriiish North Bori.c", Pa'anan, andoilierneighbour
ing islands. — Mr. Oldfield Thomas read a paper upon the
loiig-lo>t mammal Putonus iifriianus, Desm. , and its occur-
rence in M.ilta. — Mr. F. E. Beldard, F.R..S., read a paper on
the visceral anatomy of the tree-kangaroo (Dcndrolagus
henneltti), and pointed out the structure of the brain and other
organs.

CAMnRIDGE.

Philosophical Society, January 28. — Prof. J. J.Thomson,
President, in the chair. — The following resolutions were pro-
posed by Prof. Sir. G. G. .Stokes, seconded by Mr. Glaze-
brook, and passcil unanimously: (i) "That the Cambridge
Philosophical Society desires to express its sense of the great
loss sustained by the Univeisiiy and the .Society by the death
of Prof. Cayley ; whose eminence conferred honour on the
.Society which reckoned him amongst its Presidents, and whose
simple and earnest character was an ex\mple to all and endeared
him to those who knew him." (2) "That the Society do now
adjourn without transacting the business of the meeting, as a
mark of respect to Prof. Cayley."

Paris.

Academy of Sciences, February ii. — M. Marey in the
chair. — .M. Faye gave a short accoun' of the contents of
volumes iv. and v. of the Annates </e I'Obscrvatoire dc Nice. —
On the presence and distribution of alumina in plan's, by M.\I.
lierthelot and G. Andre. Alumina is found in quantities com-
parable with the amounts of other bases present, mostly in the
roots of pl.ints hiving deep and abundant roots. — Preparation
and pro| Cities of titanium, by M. Henri Moissan. Titanium
has been prepared in the electric furnace. It requires the most
intense heat capable of production, and e> en then contains at
least 2 per cent, of carbon. It forms friable ma-ses, having a
bright white fracture. It is harder than quartz and steel. Its
specific gravity i-i 487. The chemical pi Oiierties arc given in
detail. Its silicide and boride are as hard as the diamond. The

carbide, TiC, and nitride, Ti,N.,. are also fully describe 1.— On
some derivatives of phenolph'halein, by MM. A. HaUer and A.
Guyot.— M. Guignard was elected Member of the Dotany Sec-
tion.— Report on a work by M. E. Hardy relative to the
application of sound vibrations to the analysis of two gases of
difTerent densities. By means of an inUrument (termed a
FormOnophonc) consisting essentially of two pipes tuned to give
the same note, and blown wi'h air and with air containing a
lighter gas, the quantity of lighter gas pre5ent may be ascer-
tained by the production of beats between the sounds emitted
by the two tubis. — On a property of meromorphic functions,
by M llmile Borel — On certain system; of equations to the
derived partial*, by M. J. Beudon. — On the electrostatic capacity
of resistance bobbins, and its influence in ihe measurement of co-
eflicien'sof induction by the Wheatsto le bridge, by M. J. Cauro.
Bobbins with double coils should only be used for small resist-
ances ; if the resistance increases, acapacity-error greater than
that due to self-induction may be caused. To minimise
capacity-errors the Chaperon winding should be used. These
capacity effects may be neglected in measurements made with
ordinary Wheat stone bridges ; but they come into play with
bobbins having small coefficients of self-induction with great
resistances. — On the measuremement of luminous flux, by M. .\.
Blondel.— On the passage of light across a thin plate in the
case of total retl;ction, by M. Ch. Fabry. The formuI?e of
thin plates are shown to apply with )ut modification to the case
of a transparent spot at and surrounding the point of contact
of a convex and plane-glass surfaces when the included lliin
plate is viewed at the angle of total refl-ction. — On the lower-
ing of the freezing-point of dilute solutions of sodium chloride,
by M. \. Ponsot. The author obtains results by his own
method differing from those of previous observers. He finds
that in the limit the loweiingof the freezing-point is propor-
tional to the num'ier of grams of salt existing in 100 grams of
solution.— On sulphide of gold, by M. A. Diite. The be-
haviour of gold sulphide in presence of alkaline sulphides,
with and without excess of dissolved sulphur, is described. The
compounds: AH..S.2>Ia„S 2oH„0 and AuoS.Na^S. loH. O and
Au.,S.4K„S„ I2H'„0 are' noted.' — On a method of causing the
crystallisation of precipitates ; manganese and zinc sulphides
and cupric hydrate, by M. A. Villiers. — On cinchonigine, a
case of dimorphism of a compound having a specific molecular
rotatory power, by i\I\I. Ii. Juugncisch and E. Leger. Cin-
chonigine is dimorphous, its two forms readily passing
from one to the other. The monoclinic form is stable at
the ordin.ary temperature, the rhombic form at about 35°. — On
the plurality of chlorophjlls ; the second chlorophyll isolated
from lucerne, by M. A. Etard. — A comparison beiween the
coloured and colourless derivatives of bexamethyl tiiamidotri-
phenylmcthane, by M. A. Rosen-tiehl.— On a new type of
ethereal salt, methylene lacta e, by M. L-niis Henry. The
preparation and properties are described of the substance

CHj. CH . CO
represented by the formula | | . — On the rela-

O.CH3 O
tion between the general form and the composition of the body
in protozoa, by M. Fe ix Le Dantec — A study of the agricul-
tural value of the phosphate of aluminium from Grand-Connc-
labile, by M. A. Andouard. — On ihe contact phenomena of
the iheizolite of the Pyrenees, by M. A. Licruix. — New-
relations between the barom-tric movements in the iiorihern
hemisphere and the movemens of the sun and moon in declin-
ati.in, by M. P. Garrigou-Lagran,e. (l) In the northern
hemi-phere the atmosphere oscillate-i about the 30 h parallel,
corresi)onding to the movement of the moon in declination, so
that the pressures are lower with boreal thin «iih ausral moon
below 30", and inversely above. (2) The gradients take
corresponding modihca'iuns. The barometric slopes from 30°
south and north, are altern.ately increased and lowered, m .re
strongly with boreal moon below 30°, more feebly above, and
inversely with austral moon. (3) These difTerencs in pre-sures
and gradient; augment towards the pole, at least up to the 70th
parallel. (4) These movements are superposed on more general
movements.

A^tSTERIlAM.
Royal Academy of Sciences, December 29, 1894. — Prof.
Van de Sande Bakhuyzen in the chair.— .-V treatise on a simple
method of roughly disiinguishing between Scandinavian and
southern diluvial sand, atnl between alluvial and diluvial sand,
by separating (he heavy minerals from the sand through in.-

NO.

I32I, VOL. 51]

4oS

NA TURE

[February 21, 1895

mersion of the sand in a fluid of a specific gravity of 2'8S,
invented and described by Dr. J. L. C. Schroeder van der
Kolk, formed the subject of a report drawn up by Mr. Van
Diesen and Dr. Behrens — Mr. Schols and Mr. Martin re-
ported upon an e-say by Mr. J. J. A. Muller, in which
the author calculated the dislocation undergone by some parts of
the mouniain system of Sumatra, in consequence of the earth-
quake of May I", 1892. These calculations, which are based
on data supplied by the measurements executed in the said
island, on behalf of the secondary tiiangulation, prove with great
certainly a horizontal shifting of the following three points to
the extent, and in the direction indicated : —

Sorik Merapi I -23 M. 344° 57'

Tor Si Hite ... ... 064 M. 149° 2'

Goenvenjj Malintang ... I'24M. 304° 28'

the directions being counted from the north point, going round
through the easi.^Dr. Jan de V.ies discussed some meihodsof
deducing from given conliguralions more complicated con-
fignralions. In particular a series of configur.itions, first de
scribed by Andreef, was deduced from ihe tetrahedron by
means of Ji system ot polar coordinates. — Dr. Hikhuis Rooze-
boom, in considerini; the experiments of Prof. .Spring, on the
conversion of black inio red llgS, showed that this author was
mistaken in the nature of ihe phenomenon, which belongs to the
category of the conversion of unstable modifications into stable
ones. The pressure required for a conversion of this description
does not admit of being expressed by a simple law. — Dr. P.
van Romhuri;h has examined, in the laboratory ol the " culture "
garden at Tjikeumeuh, a number of coca leaves grown in Java,
in order to ascertain their volatile constituents. Those of
Erythrcxylon Cc<a Lam. var., Sprucfanum (Kurck), when dis-
tilled with water, produced melhylsalicylate (about 20c.c. was
obtained from 140 kgrs. of fresh leaves). In the water was
also found a little acetune and m^lhylic alcohol, and perhaps also
traces of salic)lic aldehyde. The quantity of methyl salicylate
decreases in proportion as the leaves grow older ; in fresh un-
expanded top leaves Dr. van Komburgh loun'l 013 per cent., in
young leaves from o 06 to 007 per cent., in old leaves even less
than 002 per cent. The leaves of Erylhroxylon Bolivianum
(Burck) were also proved to contain methyl salicylate, but only
o 0C4 per cent., as well as those of E. ecarinaliim (Burck), but
not those of E. Biirmaniunt (Grift) and E. loni^epetiilatum
(Burck), while in the case of E. spec, iiisul. Comor the results
were doubtful. — Prof Kamerlingh Oniies read a paper on the
Kryogene Laboratory at Leyden, and on the production of ex-
tremely low temperatures. The object of the author in starting his
investigations, upwards often years ago, viz. the combination of
Wroblewski's an'l Ulszew.ski's labours with those of Pictet, has
been quite satisfactorily attained with the least possible means.
Liqaid oxygen is stored in a gla^s vessel adapted for experiment-
ing and observing puiposes; the oxygen vapours are continuously
compressed, liquefied, and again poured into the said vessel, so
that the evaporation from the surface takes place at a level
pretty neatly constant. With Ihe aid of a small quantity of
ciiculaiing oxygen, a bath of liquefied gas of quarter to a half
litre can t»e maintained under normal or reduced pressure, ad
libitum. With this method no use is made of Dewar's vacuum
vc««I». The vc^s^-l IS protected from conveciive transference
of heat by the oxygen vapour, which cools a special chamber
with plaleglast windows. The-e windows remain qui'c free
from hoa'-frost, and do not in'erfere with the (orm.ilion of
images. The con'Icnsation of oxygen is obtained m a spiral
tube immersed in liquiil ethylene boiling in a copper flask
connected «iih a conjugate vacuum pump and cimpressor.
The circulating ethylene is liquefied in a condenser cooled down
to 80° by a circulation of methyl chloride, or in some casrsby
carbonic acid. The apparatus is so arranged, and the fla>k
especially is so devised, that only a minimum of conden-cd
gaset 14 required. Only onr and a /ju// kiliigiammesof ethylene
i> used in the author's ethylene ciiculaiion to obtain the above-
m'ntioned permanent liquid oxygen bath, in c<inliaili>tinclii>n
to Ihe great quantities mentioned in the accoums of Dewar's
experiments — The purifying o( ga>es by means of fractionating
at low Icmperaiurei was alto treated, and a modified (oim ol
Caillettt's mercury plunger compictsor, used specially for this
purfxise, was dociiliel. The author c nchidcd with a few
obtervations on certain inves'igaiitinsatid nppnr.iliis in course of
execution, and intendrd to I'C picpara'oty to the m inipulaiiun
of liquid hydrogen in the Kryn.enc Labuiatory ol the future.

NO. 1321, VOL. 51]

GOTTINGEN.
Royal Academy of Sciences. — In the Nachrichtcn, part
4 (1S94), the following papers of mathematical and physical
interest appear: — Fv. Schilling, the fundamental polygon of
Schwarz's 5-function for the case of complex exponents ; O.
liolza, a fti function for the general hyperelliptic case; R.
Dedekind, on ideals (in the theory of numbers) ; K. Riecke, the
equilibrium between a deformed homoi^eneous solid and liquid in
contact with it ; 1". Riecke, Cl.iusius' condition equation; A.
Hurwitz, on the theory of ideals ; R. Ilau-^sner, the numerical
coefficients of Weierstrasss trseries : G. Pick, invariant pro-
cesses for higher binary forms; A. Schonflies, the hexagonoid
of Eberhard ; P. Bachmetjew, results as to electrical earth-
currents in Bulgaria ; K. Ritler, extension of the Kiemann Roch
theorem to sets of forms ; A. Sommerfeld, mathematical theory
of the inflexion of light and electricity; W. Voigt, on piezo-
electricity in crystals without a centre of symmetry.

BOOKS, PAMPHLETS, and SERIALS RECEIVED.

Hooks.— Cod-Liver Cil and Chemistry : Dr. F. A. M. tier (Peter Mol'cr).
— Mechanics, an Elementaty Text- Bo"l(. Theoretical and Practical. Dy-
namics ; R. T. Gtazebrook (Cambtidge University Prc^s) — Colour Vision :
Captain W. de W. Abncy (Low). — The Student's English Hictionary:
Mr. J. Ogtivie. new edtti n (Ulackie). — The Story of the Star.*;; G. r.
Chambers (Newnes).— L'niversal Electrical Directory, 1895 (.Mabaster). —
On the Geographical Distribution of Tropical Diseases in Africi ; Dr. R.
W. Felkin tEdinburgh, Clay).-Philosophy of Mind : I'rof. G. T. Ladd
(toREmans).

Pamchlets — Le Service ChronoiticHtique a rObservatoire de Genfcve.
&c. : Prof. R. Gamier (Geneve, Aubert Schuchardt). - OriKen PoliMrico
de las Especies : A. Soria y Mata (Madrid, Establicimiento TtpoR'.'llico).

Serials. — Engineering Magazine, February (Tucker).— Journal ol the
Franklin Institute, February (Philadelphia). — Himmel und Erde. February
(Berlin, Paetel).— Internationales Archiv filr Ethnographic. Band viii.
Heft I (K. Paul).— Journal of the Anthropological Institute, February
(K. Paul).— Journal of the Asiatic Society of Henual, V.>1 l.\iii. P.irt j
Ni. 3 (Calcutta). — .\slrophysicaI Journal, February (Wesley). — Journal of
the Chemical Society, February (6urney).

CONTENTS. PAGE

Sir Andrew Crombie Ramsay 3S5

Our Book Shelf:—

Hill: " Harvard College by an Oxonian." — L. . . 386

Dumesnil : " Tableau Mclrique de L"gatilhmes" . 386
Rodway : " In the Gui.ina Forest. Studies of Nature

in Relation to the Struggle for Life." {/Iluslraud) 387

Wiillner : " Lehrbuch der lixperimentalph)sik. " — pv 387
Middendorf: "Peru. Beobachtungen und Sludien
iiber das Land uml seine Bewohner whhrtnd eines

25-jahiigen .Vufenthalts" 388

Letters to the Editor: —

The Liquefaction of Gases. — M. M. Pattison

Muir 3S8

Ari;on. (Illuslraled.)—V>i. J. H. Gladstone,

F.R.S 389

The Aurora of November 23, 1894.— W. H. Wood ;

Prof. A. S. Herschel, F.R.S 31)0

The American Association.— -Dr. Wm. H. Hale . 390

Earthquake in Norway.— Dr. Hans Reusch . . . 390

" The lilack-veiued White Butterfly."— H, Goss . 391

ThcZo'iiacil Light.— Rear-Admiral J. P. Maclear 391

Oysters and Typhoid 391

Notes 392

Our Astronomical Column : —

Mars in 1894 395

Novel Methods in Photometry 395

.V'mosphiric Dispersion 39^

The Sun's Place in Nature. I. (IlliislraleJ.) By J.

Norman Lockycr, C.B., F.R.S 396

Nathanael Pringsheim. By D. H. Scott 399

The Antitoxic Scrum Treatment of Diphtheria. By

Dr. G. Sims Woodhead 402

University and Educational Intelligence 406

Scientific Serials 40'>

Societies and Academies 406

Books, Pampalets, and Serials Received .... 408

NA TURE

409

THURSDAY, FEBRUARY 28, 1895.

WHAT DOES THE CHEMIST MEAN
BY " VALENCY"?
Handbuck der Stereochemie. Von Dr. C. A. Eischoff,
unter Mitwirkung von Dr. P. Walden. II. Band
(Schluss). (Frankfurt: H. Bechhold, 1894.)

THE author of the review of the first part of this book
(Nature, vol. xII.k. p. 409) has given an account
of it with which the present writer entirely agrees. Dr.
Bischoffs book embodies a tolerably complete epitome
of all that is known of a subject which at the present
time has probably a larger number of cultivators than
any other department of chemistry, and as a register of
facts and references to original sources of information it
is indispensable to the worker engaged upon stereo-
chemical problems. On the other hand, the book is not
only eminently unreadable, but the arrangement is some-
times far from clear.

Of this second and concluding volume about one third
is occupied with an enumeration, continued from vol. i.,
of the various known cases of isomerism, inorganic as
well as organic, which may be possibly referred to the
geometrical hypothesis. The second third deals with
chemical changes, such as ring formation and intramole-
cular changes regarded from the stereochemical point
of view. The last part consists of additions to preced-
ing pages, so as to bring the matter up to the most recent
date possible. Examination of a volume such as this
compels the reflection that spite of the great array of
established fact, confusion still prevails among stereo-
chemical writers, chiefly for want of some common agree-
ment as to fundamental ideas.

"Atomicity," as it used to be called, meant originally
the power exhibited by the several elements to combine
in the proportions of one atom to I, 2, 3, 4 or n atoms of
some other element. Hence arose the idea of diflTerent
atomic values in the process of exchanging one element
for another. Later, from these notions about "quanti-
valence" it was assumed (without sufficient evidence)
that when an atom, say, of carbon combines with lour
other atoms, the force of attraction or union for each of
these four atoms is the same. Attempts were then made
to estimate by thermal methods the mechanical value of
each unit of " atomicity" or " quanti valence."

During all this time much discussion has occurred as
to what becomes of units of "valency," to use the more
modern term, which are not exercised as in unsaturated
compounds generally, and Frankland's idea that even
the " bonds " belonging to one and the same atom may
saturate each other in pairs has been commonly used.

Since the observations of Van t'Hoff and Le Bel on
the relations of chemical constitution to optical activity,
and the revival of the hypothesis of spacial arrangements,
and especially in the generally adopted theory of tetra-
gonal carbon, the idea of direction which is implied in
all sp.ice arrangements has been universally adopted. As
to whether the direction in which valency can act is
fixed or variable, opinion seems a little divided, and yet
it is obvious that double linkage between two atoms, or
the formation of any closed chain of tetragonal carbon

NO. 1322, VOL. 51]

atoms (whether conceived according to Van t'Hoff or
Wunderlich, or otherwise), would be impossible on the
assumption that the valency of carbon atoms can act only
in certain directions which are quite fixed. C oncerning
this question the conclusion seems inevitable that we
must suppose something analogous to a magnetic field
between combining atoms.

But what, after all, is valency?

The fact is that while one atom of chlorine combines
habitually with one atom of hydrogen, an atom of oxygen
combines with two atoms of hydrogen, an atom of nitro-
gen with three, and so forth, and it is hardly assumption
to say that so long as the hypothesis of atoms is used to
express chemical combination,. rtiw^ geometrical arrange-
ment of combined atoms in space is an inevitable part
of the hypothesis. This was long ago pointed out by
VVollaston. The valency of an element is then the
numerical expression of its habit of combination. It is
well known to be variable, and to depend to a great
extent upon physical conditions. It may be that one
atom can only act upon another in certain directions,
but this does not render necessary the assumption that
each atom is always doing something in these several
directions, whether other atoms are present or not. This,
however, is what is assumed by those who use the term
" bond " in any of the recognised senses, or who attempt
to determine the dynamical value of units of valency.
There is some evidence in favour of the hypothesis that
combination can only occur when atoms get within
a certain maximum distance from each other, and the
possibility that isomerism may result from changes in
the distance between the atoms united within a molecule,
is deserving of greater consideration than it has hitherto
received. If we think, for example, of the exchange of an
atom of chlorine for an atom of hydrogen in, say, marsh
gas, it is difficult to believe that the chlorine atom
occupies exactly the same place relatively to the carbon
as the hydrogen atom for which it is substituted.
Reasons may possibly be found for this in the difference
of the force of "affinity" between carbon and chlorine
on the one hand, and between carbon and hydrogen on
the otner, or it may result from the " residual valency " of
chlorine acting upon the neighbouring hydrogen atoms,
or from the difference of "mass" of the chlorine and
hydrogen. But throughout all the various hypotheses
used generally by chemists, runs the idea of direction
variable within narrow limits, already referred to. Now,
however much the direction along which a force acts
may be supposed to vary according to circumstances, it
is inconceivable on any mechanical principle that one
force can act in several directions at once unless there is
reason to suppose that it is divided in some way into
component forces. Hence the " centric " formula for
benzene, which has lately come into vogue, represents a
wholly new idea which is incompatible with previously
received ideas about valency and with the hypothesis of
the tetragonal carbon atom. According to this formula
an atom of carbon is capable of acting in eight different
directions — that is, it acts directly, in the conventional
sense, upon one atom of hydrogen and upon two atoms
of carbon, at the same time that it " influences " these two
atoms of carbon and three others. This idea is wholly un-
necessary to the explanation of the stability of the benzene

T

4IO

NA TURt

[February 28, 1895

molecule, which can be accounted for quite simply in other
ways ; but it shows how prevalent is the idea that valency
means, not only the power to do something, but that
that power is always being exercised, and that in every
chemical formula every unit of valency must be accounted
for. This example is sufficient to illustrate the state of
confusion about valency and chemical combination, which
seems to grow more serious and more tangled every day.
The doctrine of Stereoisomerism as at present used
may be compared to the fluid theory of electricity.
It is a working theory which some day, perhaps,
will be superseded, but no great advance is likely
to be made until some more clear idea as to the
meaning of valency can be brought into use. In the
meantime experimental inquiry is undoubtedly proceed-

near Eaux Chaudes. The impression, at a later date,
was deepened by the marvels of Adelsberg ; and a visit
to Han-sur-lcsse Belgium) in i8S8, determined him to
explore thoroughly the swallow-holes and caves of
Les Gausses -the limestone plateaux to the south and
west of the Cevennes and .\uvergne — with which he had
already made acquaintance. Here the rivers often tlow
through deep gorges — almost canons, such as is illus-
trated by Fig. I. In iSSS and the following year the
author investigated the underground topography of the
Departments of Lozore and Gard, and then extended his
researches from X'aucluse to La Charente, going as far as
the Puy-de-Dome, the Cote-d'Or, and Provence, and,
\et further afield, to Belgium, the Karst, and the
Peloponnesus. Altogether he explored 230 " holes in the

Fir.. I. — Canon de la Daunie.

ing rapidly, and will prepare the way for the next step in
theory. To this end such a book as Bischoff's " Stereo-
chemie" will afford much assistance in the laboratory,
and can be safely recommended to all who arc working
in this direction. W. A. T.

CAVES AND SWALLOW-HOLES.
Ijs Abimes, les eaux sculeiraiiics. ks cavern, s, /, .
sources, la spelaologie. By E. A. Martel. 4 photo-
types and 16 plans, with 100 smaller illustrations.
(Paris: C. Delagrave, 1894.)

A T the outset the author remarks that the man is
•^ happy who realises in ripe manhood a project of
boyhood. As a youth he was fascinated by the stalac-
tites of the cave of Gargas, and the underground stream
NO. 1322, VOL. 5 l]

rock," which he thus classifies : Swallow-holes {(tbimcs
no, into 90 of which no descent had been previouslv
made ; emissaries of rivers [sources), 40, up 30 of which
no one had penetrated ; caves, 80, of which 45 wen
but imperfectly known. Besides these he had sounded
without descending, 35 swallow-holes, and examined 5
large emissaries, which could not be entered. Plans wen
made of underground galleries, the total length of whicl
amounts to 50 kilometres ; rather more than half tin
woik being done by himself, the rest by collaborators
The result of this indefatigable, and sometimes rathei
risky, work is the most complete original memoir on "cavi
hunting " that has ever been published, a quarto volunx
of nearly 600 pages, containing many plans, and still mon
numerous illustrations, the latter mostly from pliolo
graphs, together with a full bibliography of the subject.

February 28, 1895J

NATURE

4u

To give any account of even the caverns of the
Causses, which occupy the larger part of the book,
would occupy too much space ; so we content ourselves
with a brief sketch of one of the most remarkable — that
of Padirac, in the Causse de Grammat ; and, after all,
caves generally exhibit a strong family likeness. On a
rocky plain a gulf, nearly forty yards across, opens out
suddenly, as shown in Fig. 2, for which and the one on
p. 410, we are indebted to the courtesy of the pub-
lishers. The greatest depth is just over twice the
breadth, but a huge pile of debris rises from the bottom
up to nearly fifty-nine yards from the surface. This leads
cm either side to a gallery. One of these ascends gently
upwards, for about a couple of hundred yards, to a spot
where a stream bursts from the rock. The other gallery,

Alps, being most frequent in the more eastern region,
where sometimes a bare rocky tract is almost riddled by
swallow-holes {dolinas) great or small. From the Karst
district they may be followed through the Alps of
Dalmatia into the limestone region of Greece ; they exist
also in the carboniferous limestone of England, Belgium,
and America. One might almost say ubi calx, ibi
spelunca.

M. Martel notices, but appears to have paid less
attention to, the curious caves called glacieres, so
pleasantly described by Canon Browne in his " Ice Caves
of France and Switzerland." In these the walls are
hung with sheets and festoons of ice, and thick masses
of it cover the floors. In summer-time the temperature
inside them keeps very near to the freezing-point. M.

Vtr., 2.— Sh.llt Icl.l

t^ Ilie five ot l-'.idir.ic.

which is also traversed by this stream, extends for about
a mile and three-quarters, following a rather serpentine
course, which, in one part, bends at right angles to
its former direction. At last it ends in a lake and
a cul de sac. The cave is generally rather narrow,
not many feet in width, but here and there broadens
out into a large hall ; the roof, also, rises and falls,
its height not unfrequently being from forty to sixty
feet — occasionally a good deal more. Padirac contains
stalacites, stalagmites, and basin-shaped deposits of
calcic carbonate ; in short, is a thoroughly typical cave,
with the not infrequent addition of a huge swallow-hole.
Dozens of similar caverns may be found in this curious
limestone region. They are abundant, under various
names, in the Jura and in the limestone districts of the
NO. 1322, VOL. 51]

Martel suggests that in winter they become filled with
coldair, which remains there like the carbonic anhydride
in ?igrotto del cane. But such as we have seen, appear to
be better explained as natural ice-houses, where the
summer warmth is insufficient to dispose of the snow
and ice which had accumulated in the winter.

Is it possible that occasionally these swallow-holes and
caves may be memorials of an age when the climate was
colder than it is at present ? Both are sometimes dry.
In the case of the cave, this may be explained by the
water having worked out a new, and as yet undiscovered,
path ; but some swallow-holes open out, like the mouths
of wells, on gentle slopes or rocky plains, apparently
disconnected from any system of drainage. They seem
too large to be explained — like those countless pipes in

412

NATURE

[February 28, 1895

the rock of the Slcinerm ^fecr — as only the work of
rain. Is it possible that they were chiefly excavated in
the Glacial epoch, when many elevated rocky plateaux
would be buried under permanent, or nearly permanent,
snow-beds, the drainage from which would give a supply
of water, which was engulfed before it had the oppor-
tunity of excavating a glen ? Some things seem not
unfavourable to this suggestion. T. G. BoNNEY.

OCR BOOK SHELF.

BuUilin of tilt Botanical Departinent, Jamaica. April
18S7 to September 1S94. Edited by the Director, W.
Fawcett, B.Sc. (Published by the Department of
Public Gardens and Plantations )
.Since the increase of botanical stations in the British
West Indies, there has been greater activity in the older
establishments, and the Directors have followed the ex-
ample of Kew, in issuinga monthly budget of information
useful to planters and others, whether they plant for profit
or pleasure. We have lately received a complete file of
the organ of the Jamaica Garden, bearing the above title.
This was started m 1SS7, and it has increased from a
single page of foolscap size to a sheet of ordinary octavo ;
and the price is only twopence. The contents are of a
varied and miscellaneous nature ; but information on
the cultivation and diseases of economic plants, and on
the value and preparation of their products, largely pre-
dominates. It includes not only the results of local
experience ; the editor has also drawn upon the numerous
sources open to him, thanks to the more intiinate con-
nection between similar establishments throughout the
empire, due, to a large extent, to the efforts of the
Director of Kew.

Among other things, there are lists of the economic
plants, of plants yielding edible fruits, and of trees useful
either for timber or shade, cultivated in the Jamaica
botanic garden. Botanical and common names are
given, as well as the native countries of the respective
plants, together with theprices (of seeds or plants) at which
they are offered to the inhabitants of the island. The
prices, it may be mentioned, are ridiculously low ;
merely nominal, in fact. Free grants are also made ;
but in order to avoid waste of valuable plants, ihe con-
ditiins are somewhat stringent, though not more so than
an intelligent and earnest cultivator would cheerfully
submit to. Another interesting feature is Mr. Jenman s
descriptive enumeration of the Ferns of Jamaica. This
was commenced in 1890, and is still unfinished. It is to
be hoped that this will some day be issued separately, as
the Fern-vegetation of J.imaica is perhap-; the richest in
the world, comprising between 4C0 and 500 species.

Die \faichinfllen Hilfsmittcl Her CItemischen Teclmik.
Von A. Parnicke, Civil-ingenieur, vorm. Ober ingenieiir
der Chemischen Fabrik Griesheim. (Frankfurt : H.
Bechhold, 1894.)
We are accustomed to hear little but praise of the German
University sysie n of education. There is, however, a re-
verse to the shield While admitting the value of the train-
ing received by the University student in pure chemistry,
the author of this work points out that only in a few of
the higher technical schools isany systematic instruction
given concerning the employment of machinery in manu-
facturing chemistry. The consequence is ih.it many
young chemists find, at the commencement of their
practical career, that they have either to laboriously
collect, from many scattered an 1 not easily accessible
sources, the information thev require, or perforce remain
mere cooyists of the mclhod-i of oihcrs, for lack of the
knowledge which might enable them to intelligently
use the mechanical appliances best suited to attain their
ends.

NO.

1322, VOL. 51]

The work under review represents an endeavour to
lessen the difficulties in this direction. In some 29c
pages,a synopsis is presented of the principal mechanical
arrangements with which the chemist may be concerned.
A vast amount of information is set out in well-arranged
sequence, and, though many of the descriptions are
necessarily somewhat sketchy on account of the large
number of appliances to be described, a study of the
pages before us cannot fail to be of great use to the
limited class for whom they were written. The book is
well illustrated, having no fewer than 337 figures ; these
would have possessed a much greater value had dimen-
sions been more generally given. From the point of
view of the highly-trained chemist, it is perhaps to be
regretted that valuable space is occupied by descrip-
tions of certain machines of well-known types, such as
common weighing machines. No doubt the volume
is rendered more complete by the inclusion of such
matter, yet it would seem of far greater importance
that a chapter should have been added dealing with the
many useful types of pressure and temperature regulators
and their applications. It could hardly be expected
that all parts of the book should be equally up to date :
the account given of pyrometers is notably incomplete, no
mention being made, for instance, of the now well-known
instrument designed by Le Chatelier. Knglish students
may find in this compilation a useful index serving as a
guide to direct their attention to the most important
mechanical devices used in chemical operations ; but we
think that they will benefit more by undertaking the
additional labour of unearthing details from the many
admirable treatises and dictionaries already in existence
in their own language. W. T.

Air, Water, and Disinfectants. (Manuals of Health

Series.) By C. M. Aikman, M.A., D.Sc. Pp. 126.

(London : S. P. C. K., 1895)
This little bonk contrives to tell us a great many most
interesting and instructive facts, without for one moment
running the risk of boring us. It is written in an attrac-
tive style, and whilst popular, the author never forgets
what is due to the subjects he is discussing.

Microbes, not perhaps, without reason, furnish material
for a substantial portion of the text, and free use is made
of'' Our Secret Friends and Foes," which, however, Dr.
.Aikman amply acknowledges.

The little >ection on "Duit particles in theair" contains
an interesting ristiinc ai Dr. Aitken's investigations, and
as they have been, we believe, chiefly published in Edin-
burgh scientific journals, will doubtless suggest much
that is novel to the general reader. Many such will be
astonished to learn " that a cigarette smoker sends
4,000,000,000 particles of dust, more or less, into the air
with every puff he makes," and that one cubic inch of the
air of a room at night, when the gas is burning, may con-
tain as many dust particles as there are inhabitants of li Ci
Great Britain I " •

We cordially recommend this little book to all those
who wish to obtain an accurate, though popular, idea of
the nature of air, water, and disinfectants. |I ■

An Elementary Text-book of Anatomy. By Prof. H. E. * •
Clark. (London : Blackie and Son, 1895 )

A Ticx r-nooK of anatomy, suitable as an introduction to
juni<ir students of medicine, and sim|ile enough to be
unilcrstood by all who wish to read about the structure
r>f their bodies. The bonk is limited to the anatomy of
the human subject, and is divided into seven sections,
dealing respectively with the tissues, bones, joints,
muscles, vessels (ihe heart, blood-ve>sels, and lymphatic
vessels), nervous system, and internal organs. It con-
tains numerous instructive illustrations, as well as a useful
glossary, and is altogether a serviceable elementary
manual of anatomy.

February 28, 1895J

NATURE

413

LETTERS TO THE EDITOR.

\ The Editor doet not hold himself responsible for opinions ex-
pressed by his correspondents. Neither can he undertake
to return, or to correspond -Jiith the writers of, rejected
manuscripts intended for this or any other part of NATURE.
No notice is taken of anonymous communications. ]

Liquefaction of Gases.

In a long letter which you publi!-h»cl in Nature of February
14, Mr. Patti>on Muir charged me with .ippropriaiing the work
of Olszewski and passing it off as my own. I replied at some
length, not on account of the intrinsic importance of the at'ack,
but because there are always persons ready to assume ihat a
charge of this kind, by whomsoever made, must be unanswer-
able unless- it i* ans.vered. But a> I can conceive noihing more
unintere ling to yuir readers or mjst-lf, than a mere dialecical
controversy with Mr. Muir, my reply to his leiter published on
the 2ISI will be biief.

"A careful smdy" of my previous letter has not enabled Mr.
Muir to SI b-ianiia e his original charge of wilful piracy. On
the contrary, he entirely shilts his ground. He extracts four
clauses from my reply and proceeds to deal with them, ignoring
altogeiher the on'y question r>( the smallest imponauce, namely,
the one claim made by himself Xo have convicted me of dishonest
appropriation of anothe.- man's work.

The third claim found in my reply by Mr. Muir, which is the
all-important one, is, to use hi> own language, that in "1886 I
liquefied o.xygen by passing the gas through a long copper coil
surrounded fry liquid eihylene, an 1 that my apparatus made it
possible to tran>fer the liquid oxygen to a glass vessel wherein
it could be used as a cooling agent." Well, the only question
here is whether I did or did not do what I claim to have
done in a pnfilic leciure dvrlivered and published in the year
1886, and ihis quesiion Mr. Muir shirks.

Until Mr. Paitison Muir can declare that after trial an appa-
ratus constructed ace rding to the plan given in 1886 is essenti-
ally defective, and will not deliver liquid oxygen in a manner at
all comparab e to ihe Olszewski steel cylinder, descrihed in the
Cracow Bulletin of 1890, let him acknowledge at least that the
case of Prof. 01-zew^kl, which he championed in his last letter,
will have to be abandoned.

Having failed to overthrow a single one of the claims which
he himself after "careful study" holds me to have made, Mr.
Muir falls back upon a general attack upon the scieniific work
"that is attiihuted to the Fullerian Professor at the Royal In-
stitution." With what is attrilruied to me by others, I have no
concern. The low lemperature work that has been commenced
and so far developed in the laboratory of the Royal Insti'ution
comprises the following subjects: Construciion of apparatus
for the production of liquid air and other gases in quantity,
improving high vacuum, vacuum vessels for storage and
manipulation of liquid gases, solid air, radiation at low tempera-
tures, thermal Iranspartncy of liquid gases, refractive indices of
■oxygen, nitrogen, and air ; spectroscopy of liquid oxygen and
air, thermo-electric inversions, latent and specific heats,
■chemical action, magnetic properties, breaking stress of metals,
solid matter and argon in liquid air, phosphorescence and
photographic action, liquefaction of hydrogen, &c. The
abstracts of the results of these investigaiions have been pub-
lished, and if Mr. Paitison Muir would only take a little trouble
he cjuld find them. In due course, and when I think
proper, fuller details will be published. Mr. Muir's case is,
however, that my intellectual pap coiies from Cracow, and that
I have followe I in the wake of the researches of his client. On
referring to Prof. Olszewski's record of woik since his alleged
invention of the wa\ to use liquid oxygen as a cooling ai;ent in
1890, 1 tin! that with the exception of ihe refractive index of
oxygen, which w;is anticipated by Prof Liveing and myself, and
an attempt 10 confirm the late Prof. Wroblews i's critical con-
stants of hydrogen, the work carried on at the Royal Insiitution
and at Cracow have had nothing in common. It is not my
business to inquire why Prof. Olszewski should take five years
over this work, any more than it is legitimate for Mr. Muir to
complan that I ou^hi to have done more with my apparatus of
1886, than ciiol a piece of meteorite or expand liquid oxygen
into a vacuum. No doubt by imjilication Mr-. Muir intends to
convey that any success at the Koyal Institution was due
to the use of a steel cylinder instead of the copper
■coil of 1886, and that suggestion I have to emphatic-

NO. 1322, VOL. 5 l]

ally contradict, seeing that a steel cylinder never was
used in any part of the apparatus employed for
the liquefaction of gases. Under the circumstances it will be
for Mr. Paitison Muir to explain what new information I could
derive from Prof. Olszewski's alleged invention of 1890 which
had not been already involved in the construction and use of my
1SS6 apparatus. .\ll this, however, does not relieve Mr.
Muir from his embarrassment. He charged me with having
atiributed to myself work done by other men, and to this
charge I pin him. Having failed in his first attack, he has
changed his ground, ignored the evidence of dates and facts
which he cannot overthrow, and made a second attack in a form
chosen by himself. This also has failed ignominiously. It is
to be hoped that in future, when scientific investigators enter on
priority discussions, ihe real combatants will be left to their
polemics without the interference of third persons.

Royal Institution, February 26. James Dewar.

On Certain Questions of the Theory of Gases.

§1.1 PROPOSE to answer two questions : —

(1) Is the Theory of Gases a true physical theory as valuable
as any other physical theory?

(2) What can we demand from any physical theory ?

The first question I answer in the afiirmative, but the second
belongs not so much to ordinary physics (let us call it ortho-
physics) as to what we call in Germany metaphysics. For a
long time the celebrated theory of Boscovich was the ideal of
physicists. According to his theory, bodies as well as the ether
are aggregates of material points, acting together with forces,
which are simple functions of their distances. If Ihis theory
were to hold good for all phenomena, we should be still a long
way off what Fausl's/a'««/Hj- hoped to attain, viz. to know
everything. But the difficulty of enumerating all the material
points of the universe, and of determining the law of mutual
force for each pair, would be only a quantitative one ; nature
would be a difticult problem, but not a mystery for the human
mind.

When Lord Salisbury says that nature is a mystery,' he means,
it seems to me, that this simple conception of Boscovich is
refuted almost in every branch of science, the Theory of Gases
not excepted. The assumption that the gas-molecules are
aggregates of material points, in the sense of Boscovich, does
not agree with the facts. But what else are they ? And what
is the ether through which they move? Let us again hear
Lord Salisbury. He says :

"What the atom of each element is, whether it is a move-
ment, or a thing, or a vortex, or a point having inertia, all
these questions are surrounded by profound darkness. I dare
not use any less pedantic word than entity to designate the
ether, for it would be a great exaggeration of our knowledge if
I were to speak of it as a body, or even as a subs'ance "

If this be so— and hardly any physicist will contradict this —
Ihen neither the Theory of Gases nor any other physical theory
can be quite a congruent account of facts, and I cannot hope with
Mr. Burbury, that Mr. Bryan will be able to deduce all the
phenomena of spectroscopy from the electromagnetic theory of
light. Certainly, therefore, Hertz is right when he says:'-
" The rigour of science requires, that we distinguish well the un-
draped figure of nature itself Irom the gay-cohiured vesture with
which we clothe it at our pleasure.'' But I think the predilection
for nudity would be carried too far if we were to forego every
hypothesis. Only we must not demand too much from
hypotheses.

It is curious to see that in Germany, where till lately the
theory of action at a distance was much more cultivated than
in Newton's native land itself, where Maxwell's theory of
electricity was not accepted, because it does not start from quite
a precise hypothesis, at present every special theory is old-
f.-.shioned, while in Er gland interest in the Theory of Gases is
still active ; zide, among others, the excellent papers of Mr.
Tail, of whose ingenious results I cannot speak too highly,
though I have been forced to oppose them in certain points.

Every hypothesis must derive indubitable results from
mechanically well-defined assumptions by mathematically cor-
rect methods. If the results agree with a large series of facts,
we must be content, even if the true nature of facts is not

1 Presidenlial Address lo the British Associalion at Oxford.
- Hertz, " Untersuchungen fiber die Ausbreilung dcr cicktrischcn Kraft,
p. 3r. ^Barth, Leipzig, 1S92.)

a I 4

NA TURE

[February 28, 1895

revealed in every respect. No one hypothesis has hitherto
attained this last end, the Theory of Gases not excoplel. Bjt
this ihi. srj- agrees in so many respects with the facts, that we can
hardly doubi that in gases certain entities, the number and siz:
of which can roughly be determined, fly about pell-mell. Can
it be seriously expected that they will behave ex.icily as aggre-
gates of Newtonian centres of force, or as the rigid bodies of
our .Mechanics ? And how awkward is the human mind in
divining the nature of things, when forsaken by the analogy of
what wc see and touch directly?

The following assumptions, while not profes.sing tn explain the
mysteries to which Lord Salisbury alluded, nevertheless show-
that it is possible to explain the spectra of gases while ascribing
5 degrees of freedom to the molecules, and without departing
from Boscovich's standpoint.

Let the molecules of certain gases behave as rigid bodies.
The molecules of the gas and of the enclosing vessel move
through the ether without loss of energy as rigid bodies, or as
Lord Kelvin's vortex rings move through a frictionless liquid in
ordinary hydrodynamics. If wc were to take a vessel filled with
one gram of g.as kept during an intinitely long time always at
o C. and containing always the same portion of ether, every
atom of ether and every atom of our g.ts molecules would reach
the same average vis viva. If then wc were to raise the
tempcriture to l' C and to wait till every ponderable and every
ether atom was in thermal equilibrium, the total energy would be
augmented by what we may call the ideal specific heat. But in
actually heating one gram of gas, the ether ahv.ays flows freely
through the walls of the ve-sel. It comes from the universe,
and is not at all in thermal equilibrium with the molecules of
the gas. It is true that it always carries off energy, if the out-
side space is colder than the gas ; but this energy may be so
small as to be quite negligible in comparison with the energy
which the gas loses by heat-conduction, and which must be ex-
perimentally determined and suhtr.acted in measuring the
specific h(.at. Only certain transverse vibrations of the ether can
transfer sensible energy from one ponder.ible holy to another,
and therefore a correction for ladiant heat mu-t be applied to
observations of specific heats. These transverse vibrations are
not produced (as in the older theories of light) by simple atomic
vibrations, but their pitch depends on the shape of the hollow
space which the molecule forms in the ether, just as Hertzian
waves are not caused by vibrations of the ponderable m.itter of
the brass halls, the form of which only determines the pitch.
The unknown electric action accompanying a chemical process
augments these transverse vibraliins enormously. The geneial-
ised coordinate; of the ether, on which these vibrations depend,
have not the same vis viva as the coordinates which de-
termine the position of a molecule, because the entire ether has
not had time to come into thermal equilibrium with the gas
molecules, and has in no respect ati.iined the stale which it
would have if it were enclosed for an infinitely long lime in the
same vessel with the molecules of the gas.

But how can the molecules of a gas behave as rigid bodies?
Arc they not composed of smaller atoms? Probably they are ;
but the vis viva of their internal vibrations is transformed
into progressive and rotatory motion so slowly, that when a gas
is brought to a lower temperature the molecules may retain fur
days, or even fur years, the higher 77/ viva of their internal
%'ibration5 corresponding to the original temperature. This
transference of energy, in fact, takes place so slowly that it can-
not be perceived amid the fluctuations of temperature of the
surrounding bodies. The possibility of the transference of
energy being so gradual cannot be denied, if we also attribute
to the ether so little friction that the Eirth is not sensibly
reta'iled by moving through it for many hundreds of years.

If the ether bean external medium which flows freely through
the gas, we might find a difficulty in explaining how it is that
the source of radiant heat seems to he in the energy of ihe gas
itsel'. But I still think it possible that the source of energy of
iht electric vibralioni caujed by the impact of two g.is mole-
cules in the surrounding ether, may be in the progressive and
rotatory energy of the molecule. If the electric stales of two
molecules differ in their motions of approach and separation,
the energy of progressive motion may be transformed into
electric energy.

Moreover, it is doubtful whether emission of rays of visible
light takes place in simple gaaes without chemical .action.
Certainly the light of solium and thit of Gassiot's tubes do i
not come from gnes who^c m^ilcculet arc in ihirmal equilibrium. I

It may be objected that the above is nothing more than a
series of imperfectly proved hypotheses. But granting its im-
probability, it sulfices that this explanation is not impossible.
For then I have shown that the problem is not insoluble, and
nature will have found a better solution than mine.

§ 2. Mr. Culverwell's objections ag.iinst my Minimum
Theorem bear the closest connection to what I pointed out in
the second part of my paper, " Bemerkungen iiber einige
Probleme der mechanischen Warmeiheorie," Silz. her. dcr k.
IVitn. Acad. vol. Ixxv. 1S77. There I pointed out that my
Minimum Theorem, as well as the so-called Second Law of
Thermodynamics, are only theorems of probability. The Second
Law can never be proved mathematically by means of the
equations of dynamics alone.

Let us compare two motions of a dynamical system. At the
beginning of the second motion, let the coordinates specifying
the position of every part of the moving system, and the mag.
nitudes of all the corresponding velocities, be the same as they
were at the end of the first motion, but let the direction of
every velocity be exactly reversed. Then in the second motion
the system moves exactly in the opposite way to what it does in
the first ; hence, if for the first motion we have

/VQ
] T^°'

then for the second we must have

That is, if under certain conditions

\ T -°-
we can always find other initial conditions which give for the
same system with the same equations of motion.

In the same manner, Mr. Culverwell wishes to refute my
Minimum Theoiem. ^Ir. Culverwell's reasoning is suspicious,
because by the same reasoning we could prove that oxygen and
nitrogen do not difluse. Suppose that initially one half of a
closed vessel contains pure oxygen, ami in ihe other half pure
nitrogen ; when the difl'usion lias advanced for a certain time,
reverse the directions of all velocities, then the gases separate
again, and, according to Mr. Culverwell's argument, wc could
believe that the probability that oxygen and nitrogen separate,
is as great as the probability that they mix.

Though inleresting and striking at the first moment, Mr.
Culverwell's arguments rest, as I think, only upon a mistake of
my assumptions. It can never be proved from the equati ns of
motion alone, that the minimum function II must always de-
crease. It can only be deduced from the laws of probability,
that if the initial stale is not specially arranged for a certain
purpose, but haphazard governs freely, the probability that
H decreases is always greater than that it incre.ises. It is well
known that the theory of probability is as exact as any other
mathematical theory, if properly understood. If wc make
6000 throws with dice, we cannot p.-ove that we shall throw
any particular number exactly 1000 times ; but we can prove
that the ratio of the number of throws in which that number
turns up to the whole number of throws, approaches the more
to 1/6 the oftener we throw.

Let us now take a given rigid vessel with perfectly
smooth and perfectly elastic walls containing a given number of
gas-molecules moving fir an indefinitely long time. All rii^iilar
motions (. .^■. one where all the nioleculits move in one plane) shall
be excluded. During the greater part of this time II will he
very nearly equal to its minimum value II (min.), Let us con-
struct the ll-curve, i.t. let us lake the lime ns axis of abscissae
and draw the curve, whose ordinalcs are the corresponding
values of II. The greater majority of the ordinales of this
curve are very nearly cquil to II (min.). Mat because greater
values o( II are not malhcmalicaliy impossible, but only very
improbable, the curve has certain, though very few, summits
or maximum ordinates which rise to a greater height than
H(min.).

Wc will nowconsider a certain ordinate H, ,11 (min.). Two
cases are possible. H, may be very near the lop of a summit,
so that II decreases if we go either in the p isiiive or negative
direction along the nxis ri-|)icsenting time. The second

NO. 1322, VOL. 51]

Fep.kuarv 28, 1895]

NATURE

415

case is, that Hj lies in a part of the curve ascending to
or iiesccrding from a higher summit. Then Ihe ordinates on
<he one side of H, will be greater, and on the other less than
H]. But because higher summits are so extremely improbable,
the first case will be the most probable, and if we choise an
ordinate of given magnitude Hj guided by haphazard in the
curve, it will be not certain, but very probable, that the ordinate
decreases if we go in either direction.

We will now assume, with Mr. Culverwell, a gas in a given
state. If in this stale II is greater than H (min.) it will be not
certain, but very probable, that H decreases and finally reaches
not exactly but veiy nearly the value H (min.). and the same
is true at all subsequent instants of time. If in an inter-
mediate state we reverse all velocities, we get an exceptional
case, where H increases for a certain time and then decreases
again. But the existence of such cases does not disprove our
theorem. On the contrary, the theory of probability itself
shows that the probability of such cases is not mathematically
zero, only extremely small.

Hence .Mr. Burbury is wrong, if he concede.s that II increases
in as many cases as it decreases, and Mr. Culverwell is also
wrong, it he says that all that any proof can show is, that
taking all values of dW dl got from taking all the configura-
tions which approach towards a permanent state, and all the
configura'ions which recede from it, and then striking some
average, dWidt would be negative. On the contrary, we have
shown the possibility that II may have a tendency to decrease,
whether we pass to the former or to the latter configurations.
What I proved in my papers is as follows : It is extremely
probable that II is very near to its minimum value ; if it is
greater, it may increase or decrease, but the probability that
it decreases is always greater. Thus, if I obtain a certain
value for dHjdl, this result does not hold for every time-
element dl, but is only an aveiaije value. But the greater
the number of molecules, the smaller is the lime-inteival dl
for which the result holds good.

I will not here repeat the proofs given in my papers; I will
only show that just the same takes place in the much simpler
case of dice. We will make an indefinitely long series of throws
with a die. Let A, be the number of times of throwing the
number I, among the first 6n throws. A, the number of times of
throwing I, among all the throws between the second and the
(6« + i)th inclusive, and so on. Let us construct a series of points
n a plane, the successive abscissae of which are

I 2 3

the ordinates of which are

'•'0-'l-"-i:^-'1

let us call this series of points the " P-curve." If « is a large
number, the greater proportion of the ordinates of this new
curve will be very small. Bat the P-curve (like the afore-
mentioned Hcurve) has summits which are higher than the
ordinary course of the curve. Let us now consider all the
points of the P-curve, whose ordinates are exactly = i. We
will call these points "the points B." Since for each point
y = (A/« - i)-, therefore for the points B we have .\ = 2h ; these
points mark, therefore, the case where, by chance, we have thrown
the number 1 in 211 out of 6« throws. If n is at all large,
that is extremely improbable, but never absolutely impossible.
Let 2/ be a number much smaller than h, and let us go forward
from the abscissa of each point 1! thr ugh a distance = 6:-jn in
the direction of .<■ positive. We shall probably meet a point,
the ordinate of which <i. The probability that »e meet an
ordinate >I is extremely small, but not zero. By reasoning in
the same manner as Mr. Culverwell, we might Iielieve that if
we go backward {i.e. in the direction of x negative) from the
abscissa of each point B through a distance = ^vjii, it would
be probable that we should meet ordinates >i. But this in-
ference is not correct. Whether we go in the positive or in the
negative direction the ordinates will probably decrease.

We can even calculate the probable diminution of y. We
have seen that for every point B we have A = 2h (i.e. 2« throws
out of 6h turning up i). If we move in the positive or negative
direction along the axis of jr through ihe distance i/«, we exclude
one of the 6// throws, and we include a new one. When we
move forward through the distance 6j','«, we have excluded 6t'

NO. 1322. VOL. 51]

of the original throws, and included 6f others. Among Ihe
excluded throws we have probally 2v, among the included ones
V throws of the number I. Therefore the probable oiminution
of A is V, the probable diminution r,\ y is zvjn approximately.
Because the variation of .v was 6t'/«, we may write
dy I

~Jx ~ "3"
But this is not an ordinary difTerential coefficient. Il is only the
average ratio of the increase ai y to the corresponding increase
of X for all points, whose ordinates are = I. The P-curve
belongs to the large class of curves which have nowhere a
uniquely defined tangent. Even at the top of each summit Ihe
tangent is not parallel to ihe jr-axis, but is undefined. In
other words, the chord joining two points on the curve does not
tend towards a definite limiting position when one of the two
points approaches and ultimately coincides with the other.' The
same applies to the H-curve in the Theory of Gases. If I
find a certain negative value for d\\ 'dl, that does not define the
tangent of the curve in the ordinary sense, but il is only an
average value.

§ 3. Mr. Culverwell says that my theorem cannot be true
because if it were lt"ue every atom of the universe would have
the same average :■/,.- viva, and all energy would be dissipated.
I find, on the contrary, that this argument only lends to con-
firm my theorem, which requires only that in the course of
time the universe must tend to a state where the average vis
viva of every atom is the same and all energy is dissipated,
and that is indeed the case. But if we ask why this state is
not yet reached, we again come to a "Salisburian mystery."
I will conclude this paper with an idea of my old assistant,
Dr. Schuetz.

We assume that the whole universe is, and rests for ever, in
thermal equilibrium. The probability that one (only one) part
of the universe is in a certain slate, is the smaller the further this
state is from thermal equilibrium ; but this probability is
greater, the greater is the universe itself. If we assume
the universe great enough, we can make the probability of
one relatively smrdl part being in any given state (however
far from the state ol thermal equilibrium), as great as we
please. We can also make the probability great that, though
the whole universe is in thermal equilibrium, our world is in
its present slate. It may be said that the world is so far from
thermal equililrium that we cannot imagine the improbability
of such a slate. But can we imagine, on the other side, how
small a jart of the whole universe this world is ? Assuming the
universe great enough, the probability that such a small part of
it as our world should be in its present slate, is no longer
small.

If this assumption were correct, our world would return
more and more to thermal equilibrium ; but because the whole
universe is so great, il might be probable that at some
future lime some oiher world might deviale as far from
ihetmal equilibr'.um as our world does at present. Then the
afore-meniioned Hcurve would form a representation of what
lakes place in ihe universe. The summits of the curve would
represent the worlds where visible motion and life exist.

LUDWIG BOLTZMANN.
Imperial University of Vienna.

Oysters and Typhoid.

Willi reference 10 the article " Oysters and Typhoid," which
appeared in your last issue, it may interest your readers to know
that De Giaxa investigated some years ago the behaviour ol the
typhoid bacillus in sea-water, both in its natural and sterilised
condition. He found that in ordinary sea-water the typhoid
bacillus suffered very considerably in the competilion with
ihe numerous other water bacteria present, but it was still
identified on the ninth day after it was first introduced. In
sea-waier in which all other bacteria had been d<-stroyed, the
typhoid bacillus was delected in very appreciable numbers on
the twenly-fifth day. More recently, however, the existence of
typhoid bacilli in sierilissd sea-water has been examined by
Cassedebal, and his resulis are not in accord wiih those obtained
by Giaxa. Cassedebat found that whilst many pathogenic

I Sec Ulisse Diiii. " GrundKlfen fiir cine T hcorie der FtuictioDcn einer
rccllcn Vcriinderlichcn" ('I'cubncr,, 1S92, ? 136), or Weierstiass, Jcurnai
fur die Malhemattk^ Band 79, p. 29.

4i6

NATURE

[February 28, 1895

bacteria, amongst which »ere those of anthrax and cholera,
lived for several days, in the case of the former twenty-one to
twenty-four days, and in that of the latter thiity-five days and
even longer, typhoid bacilli were destroyed already in the course
of forty-eisht houri in sterilised sea-water. These results teiid
to contirm those obtained by Prof. Percy Frankland, who, in
his last report to the Royal Society Water Research Committee,
states that the addition of I and 3 per cent, of common salt to
ordinary Thames water into which typhoid bacilli were intro-
duced, acted very prejudicially on the latter, although it
stimulated the multiplication of many forms of water bacteria
picicnt in a most astonishing manner. Similar results were
obtained with salted but sterilised Thames water infected with
typhoid bacilli, and not only did the latter disappear very
rapidly, but the typhoid colonies which were obtained on plate-
cultures from this salt water exhibited in some cases a very
abnormal appearance, attributable to the degeneration of the
typhoid bacilli under these conditions, for on passing such
colonies through a further process of plate-culture, they returned
to their ordinary type.

Giaxa also experimented with fish, introducing pathogenic
microbes /cr c.c. Unfortunately, he did not select the typhoid
bacillus for these experiments, but took instead cultures of
cholera and anthrax bacilli. He found that in both cases these
micro organisms were entirely destroyed in the course of a few
hours. Experiments were also made with oysters and some
varieties of mussel-fish. .\ small hole was bored in the shell,
and vigorous broth cultures of anthrax and cholera bacilli were
respectively introduced, after which the aperture was caicfuUy
closed with sealing-wax, and whilst some of the molluscs weie
replaced in sea water, others were kept in glass dishes without
any water. The latter lived for two days under these conditions.
Six hours after the injection had taken place, and again at the
end of twenty-four and forty-eight hours, the sealing-wax was
removed and a small quantity of the fluid within the shell was
taken out and plate-cultures made. In the majority of the ex-
periments these pathogenic microbes had completely disappeared
in six hours, whilst in only two instances were they detected in
small numbers at the end of twenty-four hours, and in no case
were they identified after forty-eight hours. These results were
irrespective of whether the moUu-c was kept in or out of water.
In these investigations, therefore, there would appear to be no
evidence that these pathogenic microbes (cholera and anthrax)
were capable of being transmitted by means of these jliell-fish.
.So far as I am aware, no one has followed up these interesting
experiments, and in view of the serious allegations which have
lately been made against oysters as transmitters of typhoid
fever, it is a subject which might well claim reinvestigation.

February 13. G. C. Frankland.

The Occurrence of very Cold Days.

It is usual to estimate cold by minima of temperature. Hut
we may also consider it as expressed in maxima. A day may
fairly be called " very cold " in which the maximum is not over
freezing point. I propose to offer some account of the occur-
rence of such days at Greenwich in the fifty winter seasons
(November to March) 1S44-5 to 1S93-4. (For brevity, I will
designate each winter by the year in which it begins.)

These very cold (l.iys are not very frequent. In some winters
there are none. The highest number is 27. The list is as
fallows : —

1844 ..

>3

1861 ..

• 5

1878 ..

. iS

4S ••

. —

62 ..

79 -

. 10

46 ..

. II

63 ••

• 4

80..

. 12

47 ■

4

64

• 5

Si .

. —

48 ..

2

65 ••

82 ..

2

49 ■

• 7

66 ..

. 12

83 •

. —

SO

. —

67 ..

. 6

84

1

51 ..

. —

68 .

1

85

• 3

S» •

. —

69

. 8

86 .

• 5

53 •

■ 4

70

10

87

■ 5

54 ■•

• «S

7' •

1

88 .

2

55 •

. 4

72

1

89 .

I

56 ..

• 3

73 ■

■ .1

90 .

• 27

SZ •

3

74 ■

• 5

91 ■

■ S

58 ..

1

75

4

92 •

• 9

59 ■

. 6

76

. - -

93 •

■ S

60 .

9

77 •

. —

The total, 251, gives an average of 5°02 for each season.
Ten of the winters had none of those days, and fifteen had
numbers over the average.

The distribution in months w.is as follows : —

November.

December.

Tanu.-ir>*.

Febru.iiy.

M.lrcl

6 ...

96 .

1 II

34

4

Average —

1-92 ..

. 222

.. -68

Such days are rare in November ; and still more rare in
March. The six cases in the former month were in 1S49,
185S, 1861, 18S7, and two in 1S90 ; the earliest in the month
being that in 18S7 (16). The four cases in March were all in
one year, 1845. January h.is most of such days (about 17 per
cent, more than December).

The largest number in any one month was sixteen in
December 1890 ; the next, twelve in January 1867 and January
iSSi.

We might perhaps note that relative maxima of the seasonal
numbers occurred in 1854(15), in iSt')6 (12), in 1878(18), and
in 1890 (27) ; giving three intervals of twelve years.

Measured by mean temper.iture of the three winter months,
these winters were all severe (considerably under average) except
I Sot) ; in which, though January (1S67) was very cold, December
and February were both mild (the latter uncommonly so) ;
thus the winter was above the average of mean temperature.

Days witii Maxima not vier 32" at Greenwich.

1840 '45 '50 'GS 'eO '65 '70

00 '86

NO.

1327, VOL. 51 J

Total

251

Thcie very cold days most often come in groups (two or mon
in succession). The larj;cst group was 10 in December '90 ;
the next, 9 in January '81 ; then 6 in December '44, December
'59, and January '93, kc.

(If the 251 days, 100 had maxima from 31' to 32° ; 51 from
30° to 31 ; 42 from 29" to 30° ; 23 from 28° to 29" ; 14 from 27
to 28° ; and 21 under 27", ranging down to 19". The corrc
sponding minima range from 29 '6 down to 7''7, with grcalesi
density about 22" to 24° (45 cases).

How are the maxima related to their respective minima?
There is, of course, no rigorous proporlionaliiy ; and we may
often find high maxima with very low minima {e.g. Dicemlier
29, '60, max. 3i'''8, min. lo°o), as also low maxima with rela-
tively high minima {e ff. January 15, '50, ni«. 26°-9. mi".
25°-9). On an average, however, high minima go with high
maxima, and low with low. Take the following :

I selected the cases in which the maxima was under 27°;
there are 21. ' >f the corresponding minima only fmir were over
20". On Ihe other hand, taking the l.i>t 21 (of 46) c.iscs in
which the maximum was over 31 'S, one finds only lourminimB
iindir 20°. 1 he average minimum in the former case was l6°'4 ;
in the latter 24''4. I he average difference of maxima and
minima was in both cases about 8".

February 28, 1895]

NA TURE

417

It may be useful to put down a number of the coldest of these
days (reckoned by maxima). Here are 12 :

Max. Min. Diff.

I.

Jan. s, '94 ••

190

2.

Jan.' 4. '67 ■■

21-2

%

Dec. 21, '55 ..

232

4-

Dec. 22, '90 .,

237

.S-

Dec. 22, '55 ..

24-2

6.

Ian. 10, '91 ..

24 '4

7-

Dec. 31, '74 ■

24-5

8.

Jan. 7, '94 ..

24-5

<>•

Jan. 16, '81 ..

24 -6

10.

Ian. 15, 'Si ..

24-8

II.

Mar. 13, '45 ■

24-8

12.

Jan. 14, '67 ..

24 '9

12-8

77
170

'34
i6-9

IZ'O

iS-5
iS-i

177
140
13 I
139

6-2

13s
6-2

103

7-3
1 24
60
6-4
6.9
108

"7
I I o

These minima, it will be seen, range from ']''•'] to i8''5. I
do not enter on the question as lo the coldest days measured by
minima ; but from a table by Mr. Charles Harding, giving the
minimum at Greenwich in each winter, 1841-S9 {Quart. Journ.
of K. Mel. S. vol. xvi. p. 165), extended 10 '93, I take the fol-
lowiDg cases (adding the maxima since '44) :

Diff.

Min.

Max.

(Jan. 9, '41 ...

40)

I. I-m. 5, '67 ...

6-6

■ 32-5

.. 25-9

2. Feb. 12, '45 ...

77

293

.. 21-6

3. Dec. 25, '60 ...

8-0

300

22-0

4. Dec. 25, '70...

9-8 .

282

18-4

5. Feb. I9,'5S- •

Ill

33 4

.. 22-3

6. Feb. 12/47 ..

1 1 -2

396

.. 284

The lowest (4°o) was in '41, and so beyond our fifty years'
limit. It will be observed that those six maxima are all higher
than any in our first list, exhibiiing a wide range in the tem-
perature of the very cold days thus measured.

In the present remarkable season, there have 'oeen, up to
February 27, 17 of our "very cold" days, viz. 6 in January,
and II in February (an unprecedented case). The lowest
maximum is 27° 'o, occurring on February 6, 7, and 9 ; the re-
speclive minima, I5°'I, 9° 6, and io°'2. A. B. M.

Hesper and Phosphor.

In his " History of the Inductive Sciences" (vol. i. p. 149,
London, 1S47), Whewell says: — " Pythagoras is said to have
maintained that the evening and morning stars are the same
body, which certainly must have been one of the earliest
discoveries on this subject : and indeed, we can hardly con-
ceive men noticing the stars for a year or two without coming to
this conclusion " (<r/. " The Planet Venus," by W. J. L., in
Nature, vol. xlix. p. 413). Now, what Whewell deemed so
hardly conceivable appears to have actually occurred in old
China. Wang Chung, the philosopher (ciVca 27-97 a.d. ), in
bis work, renowned for its total repudiation of the then current
errors, writes as follows : — " In the * Book of Poems * it is said,
' A'/-m;'H^( Phosphor)exisls in the east, and C43«fXvzH^( Hesper)
in the west.' In fact, however, ibey are but the phases of
Jupiter and Venus, which, appearing now in the east, now in
the west, received such distinct names from the ignorant bards "
(" Lun-hang," Miura's edition, Kyoto, 1748, torn. xvii. pp. 12-
13). Two facts are manifested in this passage. First, it shows
that, celebrated for their astronomical acquirements in very
archaic ages, as they are, the fact that the evening and
morning stars are the satr.c body, was not known to the Ctiinese
of theeighth century B.C., when the poem entitled "Ta-tung"
was composed, comprising the above-quoted line. Secondly, it
shows that, even after the identity was established of the even-
ing and morning stars, some Cliinese, so well learned as Wang
Chung, were ignorant of their own error; affirming that Jupiter
as well as Venus appears now as Phosphor, now as Ilespcr,
they have admitted the existence of two distinct Phosphori and
two distinct Hesperi, and of a Phosphor essentially difTerent
from a Hesper. It is probable that some later scholars hive
tried to evade this intricacy by aibitrarily apportinning the two
phases between the two planets ; thus, Minamoto-no-.Shita-zau,
the Japanese poet and glossarist (909-983 a.d. ), referring to a
Chinese work " Kien-ming-yuen," which is perhaps lost now,
identifies Jupiter (in Chinese : Sui sini^) with Phosphor (in

NO. 1322, VOL. 51]

Japanese : Aka-boshi), and Venus (in Chinese : Tai-peh) with
Hesper (in Japanese: YiJtsutsu) (" WamyC Ruijusho," Nawa's
edition, Kyoto, 1667, torn. i. p. i).

February 22. Kumagosu Minakata.

The Recent Storm in the United States.

The storm of February 4-9 in the United States was notable
for its extent and severity, recalling the memorable blizzard of
March 1888. The Government Weather Bureau gives the
following comparison of the two : —

i388.

1S95.

Snow

2 feet

5* inches

Wind

50 miles

60 miles

Temperature at New

York

4 '8 above

3 below

Area'...

400 miles

1600 miles

radius

radius

It will be seen that the recent storm was more severe in
everything except the amount of snow, and far more ex-
tensive. The entire southern portion of the ouniry expe-
rienced severe cold, destroying fruits and vegetables to the
value of 15,000.000 dols. in Florida alone. The zero line
extended below the middle of Arkansas, and well down into
Texas.

The storm reached New York on Thursday, February 7. On
the previous afternoon, at about four o'clock, I observed at
Brooklyn the unusual phenomenon of a double rainbow.

Brooklyn, February II. Wm. H. Hale.

SOME SUGGESTIONS ON THE ORIGIN AND

EVOLUTION OF WEB-SPINNING IN

SPIDERS.

IT cannot be reasonably doubted that one of the most
interesting features connected with the natural
history of spiders, is their habit of gaining a livelihood
by spreading nets for the capture of prey. It may be
that the large share of the attention of naturalists that
this habit has attracted, is to be attributed to the fact
that it appears to be confined in the animal world to
spiders and men. This circumstance is of itself suffi-
ciently remarkable to call for special comment ; but its
interest is not a little enhanced by the reflection, that
since spiders made their appearance in the history of
animal life vast ages before man came upon the scene,
none of us can justly claim that any member of our
own kind was the first in the field in the invention of the
art of netting. Possibly, indeed, the oft-repeated and
unavoidable observation of the efficacy of a spiders web
for the purpose of catching otherwise unobtainable prey,
may have roused in the brain of some intelligent hunter
amongst our ancestors, the idea of the practical utility of
a similar instrument for the capture of fish or other
eatable forms of life. But if this be so, civilised man
has long forgotten the debt of gratitude he owes to
spiders. For, to the average individual amongst us, a
spider is a thing to be looked upon and spoken of with
fear and dislike amounting to loathing, and to be
ruthlessly destroyed when a safe chance of destruction
is afforded.

Itis, perhaps,on account of this widespread repugnance
that the science of arachnology has claimed within the
last century far fewer students than many another less
instructive branch of zoology. Moreover, such attention
as it has received, is no doubt largely due, as suggested
above, to the wonderful web-building powers that spiders
possess. But those who have devoted their time to the
study of webs, have, for the most part, contented them-
selves with observing and recording the structure and
method of formation of the various types of nests and
snares, and in claiming or disputing their value as a
basis for a natural classification of the animals that make
them. This has resulted,- if in nothing else, at least in
the accumulation of an array of facts sufficiently vast to

4I>^

NA TURE

[February 28, 189-

make it possible to attempt to weave them into a

coherent and intelligible whole, by tn-ing to trace the
origin and evolution of the habit of net-soinning. It is
strange that but a small number of students seem to
have occupied themselves with this most attractive
aspect of the subject. With the exception, indeed, of a
few authors who have here and there thrown out stray
suggestions upon particular points, no one appears to
have seriously set himself to the elucidation of the whole
problem. It is true that in the second volume of his
work upon the American orb-weaving spiders, Dr.
McCook devotes a chapter to the "genesis of snares" ;
but since he does not appear to be able to attach great
importance to the evidence in favour of evolution, his
treatise on the subject practically resolves itself into a
demonstration of the fact that, by starting at any point
you please, in what is called " aranead spinning work," a
series of gradations may be traced from one modifica-
tion of architecture to another, from the simplest to the
most complex, or from the most complex to the simplest.
He thus succeeds in leaving his readers completely in
doubt as to whether or not he intends one or all of his
attempts at tracing the "genesis' of snares to represent
what has actually occurred in the course of nature; and
one closes the chapter without satisfactorily ascertaining
if its writer has any definite views respecting a primitive
form of spinning work. 'Set, at the same time, it must
be admitted, an impression remains that the suggestions
that are put forward, based as they are upon an extensive
knowledge of the subject, point in more than one instance
to the true lines along which the web spinning habits
have been evolved.

In attempting to arrive at an understanding of the
origin of any structure or instinct in an animal, one
nowadays naturally refers for an explanation to what is
hypothetically its ancestor, or, failing this, its ancestor's
nearest ally. If this method of research be adopted in
connection with the spinning powers of spiders, it is
found that silken threads are fabricated by two allied
groups of animals, both of which are believed by some
students to stand, in many respects, nearer than spiders
do to the ancestor of the class to which spiders, scorpions,
mites, &c., belong. In one of these — the Chelifers, or
book-scorpions — the presence of silk glands has long
been known. In the other — the /"//rj/i/V/o-- their exist-
ence is now, for the first time, I believe, pointed out.
Thefunction of the silk in the Chelifer is cocoon-spinning ;
and that it is materially the same in the I'hr\nid<r is
shown by the easily verified fact, that the egg-case of the
mother is secured to the lower surface of her abdomen
by fine silk-like threads. One of the chief interests of
this discover>' lies in the circumstance, that of existing
animals the Phrynidir appear to be most nearly allied to
the immediate ancestor of the spiders. We are, there-
fore, justified in concluding that originally the silk in
spiders was utilised for the purpose of making a case for
the eggs.

If, however, we consider the question from the stand-
point of spiders alone, it seems to me that we should
naturally arrive at the sa'ne result. For it n, ^ priori,
probable that the primitive form of spinning industry was
that particular kind which is now common to all groups.
But when we pass in review the spinning work of the
various tribes of spiders, we find that the habits of
titilising the silk for constructing a snare, or drag-lines,
for enswathing captured prey, or for purposes of locomo-
tion, do not occur, by any ineans, invariably throughout
the class. In fact, we cannot say of any one of them
that it is characteristic of spiders. Not so, however, is
it with cocoon-spinning. For, however dilTcrenl from
each other m structure spiders may be, and however dis-
similar in habits and mode of life, we yet find that the
instinct of the mother to spin a cocoon for the protection
•of her eggs is never wanting.

NO. 1322, VOL. 51]

Granting, then, the possession of silk-glands inherited
from an ancestor, we may conclude that the first step in
the development of web-spinning was the formation of
the cocoon. What was the second .' We know that a
spider's care for her eggs does not, as a rule, cease with
the completion of the cocoon : some species carry it
about with them ; others mount guard in its vicinity.
Possibly the former was the original method of disposing
of it. But if so, since such a habit must more or less
impair the mother's activity and must render her a con-
spicuous object of attack, we can understand why it has
been abindoned for the latter method by the great
majority of spiders, and is now almost confined to those
species in which the nomadic mode of life reaches its
highest development. If, on the other hand, as seems
more likely, the primitive habit was that of watching by
the cocoon, we can understand that during the tem-
porary period of quiescence thus enforced, the mother
would naturally seek concealment and protection for
herself; and since she possessed the instinct and material
for constructing a receptacle for her eggs, it is possible
to see how a slight modification of intelligence might
have led her to extend the same protection to herself by
weaving a covering over and around the retreat in
which she had sought refuge. Then if an aperture for
ingress and egress, for purposes of feeding, were left at
any spot in the wall of such a protective domicile, there
would arise, in a rudimentary form, what is known as the
tubular nest or web. .\nd the next simple but important
step would doubtless be the adoption of the silken tube
as a permanent abode for the mother after the dispersal
of the young to shift for themselves.

As a matter of fact, some spiders have advanced no
further than this stage. The females of some Drnssiiiic,
for instance, spin a temporary retreat for themselves and
their young at the breeding season ; while others utilise
the retreat as a permanent dwelling-place. Lastly, the
view that the forination of a tubular retreat was in re dity
the second stage in the evolution of web-spinning, seems
supported by the circumstance that the tube, whether
accompanied or not by accessory developments, is, with
the exception of the cocoon, the most constant feature in
the spinning industry of spiders.

Adopting then, for these reasons, the conclusion that a
simple tube was the priinitivc form of nest, it seems that
the evolution of web-spinning has been carried out along
two main lines. Along one there is a gradual elaboration
of the tube until it culminates, so far as structural com-
plexity is concerned, in the trap-door nest with which
everyone is familiar ; along the other, the tubular nest
either ultimately disappears, or, retaining its primitive
simplicity, it is to a greater or less extent superseded by
the formation of a new structure — namely, the net
for ensnaring prey.

It will not here be necessary to enter upon a discussion
concerning the various forms of tubular nests that are
constructed ; but a few words respecting the probable
origin of the door-making habit may prove of interest.

In the first place, it is important to note that the remark
able instinct to close the aperture of a tubul.ir nest with
a movable lid is possessed by spiders belonging to two
groups. These are \Mc I.ycosuia:, or wolf-spiders, of which
the .South European 'I'aranlula is a historical example,
and the gigantic Aviciilariidr, which have won such a
bad name for their alleged bird-catching propensities.
But although there is no direct genetic altinity be
tween the species coinposing these two families, it i>
nevertheless highly interesting to note that they present
a close parallelism in nest architecture. In both there
arc species which form no nest, others which construct
a simple silken tube, and others which close the
aperture of the tube with a hinged-door. Yet it is certain
that the last-named instinct has been independt-nili
acquired in the two cases. Moreover, it is probable, a!>

Febkuarv 28, 1895 J

NA TUKE

419

will presently be explained, that in both cases it has been
brought to its present state of perfection under stress of
the same adverse conditions of life. As is well known,
Mr. Moggridge long ago suggested that the instinct to
construct the door may have arisen from the habit of
closing the aperture of the tube in the winter and open-
ing it again in the spring. This idea, in substance, has
been adopted and further developed by Dr. McCook,
who states, upon the authority of Mrs. Treat, that a North
American species of wolf-spider [Lvcosa //^r/w,?) has
acquired the instinct of sealing up the aperture of her
nest during the breeding season of the Mason-wasps ;
for at this period these insects scour the country for
spiders, in order that they may lay up a store of food for
their young. When the wasps have disappeared with
the close of their hunting and breeding season, the
spiders venture again to remove the covering of their
nests ; but Mrs. Treat has made the further important
observation, that some examples leave the covering
attached at one point. Thus a genuine, though roughly-
formed, trap-door nest is produced. In view of this cir-
cumstance, there cannot be much doubt that the per-
manent and highly-finished trap-door nest of the Russian
Lycosa opifex has been similarly brought about, as M.
Wagner, the discoverer of the species, has suggested,
under the stress of the dire persecution from wasps to
which spiders in general are subjected.

Being thus able to trace with some degree of certainty
the steps by which the trap-door nest has been evolved
in one group of spiders, namely, the Lycosidtc, we are
justified in concluding, at all events until evidence to the
contrary is forthcoinLng, that it has been evolved in the
same way in the case of the Aviculanithc — the trap-door
spiders par cxcelloite.

The primary influence, then, that has been at work in
guiding the evolution of the architecture of the tunnel-
making species, has apparently been that great necessity
for the preservation of life, the avoidance of enemies,
liut if we turn to the other line, along which the web-
building instinct has been developed, we find that the
primary guiding influence has been that second great
vital necessity, the acquisition of food.

As has been already stated, the origin of the webs
which function as snares seems to be referable to a
simple silken tent or tube, similar to that from which all
the niore or less complicated forms of tubular nests
appear to have been developed. Perhaps the most rudi-
mentary form of snare arose, as Dr. McCook has
suggested, from the chance spinning of a few stray
threads about the mouth of the tubular retreat ; or,
perhaps, an irregular network of threads spun around the
aperture to interfere with the entry of such enemies as
wasps, was the first step in the evolution of net-spinning ;
nr even lines anchoring the tube securely in its site
might have first served the purpose of catching prey.
liut, however this may be, it is clear, as Dr. Romanes'
has poined out, that "there is much potential service
to which the power [of net-spinning] may be put with
reference to the voracious habits of the animal. ' Taking
this into consideration with the variation in structure
presented by different species of spiders, it is not sur-
prising that there are many modifications of the net.
Sometmies it is a thick, closely-woven horizontal sheet,
which is continuous at one extremity with a tubular
retreat, as in the case of one of our commonest house-
spiders, Tc'i^enaria ; or, as in the equally common Aiiuiu-
robius, the net is less regular in shape and less thickly
woven, but is still continuous, with a silk-lined hole, in
which the spider lurks ; or again, the web, as in P/io/ius
or 'J /leriitiinii, may be composed of an irregular mesh-
work of interlacing threads, without any such tubular
retreat as that constructed by Ta^icnana or AiiuxKrobius ;
or, lastly, it may be composed of radiating and concentric

' "Animal Intelligence," p. aoS.
NO. 1322, VOL. 51]

lines, like that of our garden spider, Epeira : and it
seems to be generally admitted that this orbicular web of
Epeira manifests the greatest perfection of instinct, and
is therefore to be regarded as the highest form of this
kind of spinning-work. Consequently, the question con-
cerning the possible steps by which such a structure has
been evolved cannot fail to be of interest.

In the first place, if all snares are traceable back to a
common tubular origin, it may be taken for granted that
those that are still associated with a tubular retreat are,,
cateris paribus, of a more primitive type than those in
which the tube has been abandoned. Furthermore, it may
be confidently assumed that the habit of weaving the lines
of the snare radially and concentrically in a definite and
elaborate pattern, was preceded by the habit of arranging
them irregularly and without order. Looked at from this
point of view, the web of a Te^enaria or Amaurobiiis is a
much less specialised structure than that of an Epeira.
It may consequently be concluded that the complete
orbicular snare of the latter animal, and of orb-weavers
in general, has been derived from one which, like that of
the tunnel-weavers, ivas composed of irregularly crossing
threads, and was continuous at one extremity with a
tubular domicile. Having arrived at this conclusion, we
naturally appeal to nature for corroboration, and search
for connecting links. Nor need we look far. For, taking
first the tunnel-weavers, we find that a species of Dictyna,
a spider nearly allied to our common Amaurobiiis, con-
structs a snare of which the threads are arranged radially
and concentrically, but so roughly that the resemblance
to the finished structure with which we are familiar in
our garden-spiders is only remote. Nevertheless, one
cannot avoid the conclusion that it represents an initial
stage in the developinent of the perfect orb.

Turning, in the next place, to the orb-weavers, we
naturally look out for snares constructed upon a more
primitive plan than that which is typical of our English
species of Epeira. But if there be any such in existence,^
we should reasonably expect, in accordance with our
hypothesis, to find these simpler kinds associated with a
tubular retreat. And our expectation would be justified
by facts. For the large and handsome tropical genus
Nephileni^ys spins a web which is structurally interme-
diate in character between \\rA\.Ci{ Epeira diadctnala{s>\ix
garden-spider) and that of the tunnel-weaver, Die/yna.^
This web resembles that of Tegeiiaria and Dictyna, in
consisting of a long silken tube, with an expanded
funnel-shaped mouth opening directly upon an extended
network of threads. But the latter, instead of being
fashioned like that of the majority of tunnel-weavers,
consists of a scanty mesh-work of lines arranged radially
and concentrically with respect to the mouth of the
funnel. In this particular it is similar to the net of our
garden-spider, Epeira; but its area, instead of forming
a complete circle, extends over only about one-third of
this figure. The importance, however-, of this distinction
breaks down when the webs of other species of orb-
weavers are taken into consideraton. For it is found
that those of the Malaysian Epeira bcccarii, as figured
by Mr. Workman, and of the North American Epeira
lahyriiitliea of Hentz, are completely circular, and yet the
radial threads at the centre of the web spring from the
mouth of a long silk tube, in which the spider lurks.

To all intents and purposes, therefore, there are not
many links missing in the chain which starts with the
web of a tunnel-weaver, like our house-spider Tegenaria,
and terminates with that of our garden-spider Epeira.
Furthermore, from the web of Tegenaria gradations
may be traced backwards to the simple tubular retreat

1 I have to th.tnk my friend Mr. H. \. Spencer for sketches of the web ot
•a species of this spider, and .-ilso for a living example of theaitinial which he
kindly brought to me from Durban, while acting as medical oflicer on
board the s.s. .l/r.i/Vaw. I was forttinalc enough to keep this spider alive
for several months, and was thus enabled by person.al observation to satisfv
myself of the accuracy of Mr. Spencer's representation of the web.

420

NATURE

[February 28, 1895

of some of the tunnel-weavers belonging to the family
Drassida, which merely construct a web to serve as a
nest during the breeding season.

But to strengthen the probability that such an evolution
of webs has ever occurred, it is necessary to be able to
show in what respects a snare composed of radiating
and concentric lines may excel in efficacy the sheet- like
web of a Tegenaria or the tangled mass of threads of a
Phalcus.

Firstly, it seems clear that threads which radiate
directly from the spot where the spider is stationed,
must more rapidly and more certainly inform her
of the position of a struggling insect than irregularly
crossing threads, which must spread the vibration
indiscriminately in all directions ; and the advantage of
there being as little delay as possible on the spider's
part, between her perception of the vibration and her
arrival at the spot, where it originates, will be readily
understood by those who have observed powerful insects
break loose from the web before being seized by the spider.
Secondly, the object of the concentric lines is evidently
to support the radii and to fill up the spaces between
them. It may perhaps be urged, however, that these
two ends would be apparently more satisfactorily
attained if the inter-radial areas were filled in by a
complete sheeting of web, or, at all events, by a larger
number of threads than is used by an Epcira for this
purpose. But it must be remembered, in the first place,
that in proportion as the mesh of the web becomes closer,
the whole structure is rendered more and more liable to
be beaten down by the rain, or blown into shreds by the
wind, unless its supports are correspondingly multiplied ;
and in the second place, that every thread of white silk
that is added to the web, tends to make it more and more
conspicuous, and so to convert it into a visible object,
which will serve as a warning to wary flies, and as an
attraction to marauding wasps. And these are the two
ends which it is particularly the spider's interest to
avoid, inasmuch as they are alike detrimental to its
chances of life.

It is legitimate, therefore, to conclude that the
principal, if not the sole factor that has guided the
evolution of the orbweb, has been the advantage gained
by a delicacy of construction, involving comparative
invisibility. But the making for invisibility has been
kept in check, and has not been permitted to go to the
length of interfering with the efficacy of the web as a
net, for which a closeness of mesh and strength of
thread sufficient to intercept and hold insects is a vital
necessity for the spider.

.Seeing, then, the advantage of the radiating threads as
rapid and sure transmitters of vibration, and the necessity
for a net as inconspicuous and delicate, and yet as strong
as possible, we are led to inquire if the method of filling
up the inter radial spaces with concentric lines is not
calculated to afford the greatest possible support to the
radii. This inquiry must, I think, be answered in the
affirmative. For if, as is the case here, the threads be
drawn from points on one radius to points on another, so
as to make the two interior angles on either side of them
equal, these threads are the shortest that can be made ;
and the shorter the threads, the less their elasticity,
and the greater the support they supply to the radii.
This fact alone has been, one would think, of sufficient
importance to bring about the concentric arrangement
of the supporting lines. But more than all this, it is
also to be borne in mind that the shortest threads
utilise the smallest quantity of silk, and take the shortest
time to spin. .So that, in constructing a net of radiating
and concentric threads, it appears to me that an Kficira
economises both time and silk, and in addition renders
her snare as strong and as serviceable, and yet as
delicate and invisible, as possible.

K. I. I'OCOCK.

NO. 1322, VOL. 5 l]

NEW METRIC STANDARDS.

•yHF, President of the Royal Society, with Sir John
-*■ Evans, and the following members of the Council —
Dr. .A. A. Common, Mr. W. Crookes, Dr. A. R.
Forsyth, Prof. H. Lamb, Prof J. H. Poynting — visited
the Standards Department of the Board of Trade on
Thiirsd.ny. thecist inst., for the purpose of inspecting the
new metric standards which h.ive been recently deposited
with the Department. The President and Council were
received by Sir Courtenay Boyle, K.C. B.,the Secretary of
the Board of Trade, and Mr. H. J. Chaney, Super-
intendent.

Two new metric standards, of length and mass respec-
tively [lii's prototopis natioiiaiix), were delivered to the
Board of Trade by the International Committee of
Weights and Measures at Paris on September 28, 1SS9,
and the third and final standard was received from the
Committee in December last. All three standards are
deposited at the Standards Office, 7, Old Palace Yard,
Westminster, and are available for use in the verification
of metric standards for the purposes of science.

The two standards received in iSSg include a "line"
standard metre measure {tiutrci'ttTails) and a kilogramme
weight. The standard received last year is an " end "
standard metre {miirc-d-lioiils). Those three standards,
together with other similar standards supplied to twenty-
one different Stales, are, inter alia, the outcome of the
results of the labours of the International Committee for
more than twenty years ; and Great Britain is the first
country which has received all three of such standards.

The standards were verified at the Hureau International
dcs Poids et Mesure {Pavilion di liretcuil, Slvres, prh
Paris), which bureau was established under a Metric
Convention, dated May 20, 1S75, signed by twenty
different High Contracting States, exclusive of (ireat
Britain, who finally joined the Convention in September
1884. The Commutee is a self-elected body, and is
founded and maintained by common contribution from
all countries who are parties to the Convention of 1S75.
The bureau of the Committee is required to be near
Paris, and has been declared to be internationally neuter.
The Committee was charged in 1S75 with the construc-
tion, restoration, and verilication of new metric standards
(des prototypes iiiternationaux) to replace the ancient
standards oi p" ranee (iiiltrc et Iciloi^rainine des are/ii:es),
and with the verification of copies of the new standards
for all the contracting States. By such means the inter-
national accuracy of metric standards is now assured
throughout the world.

The Committee, which includes thirteen members,
undertakes also the verification of standards for scientific
authorities or persons.

T/ie Mitre.

The two metric standards above referred to are made of
iridio-plalinum, or an alloy of go per cent, of platinum
and 10 per cent, of iridium. The metres are in transverse
sections, nearly of the form of the letter \, known as the
Tresca form, and selected as being not merely as the most
economical (iridio-platinum being a costly metal), but as
being less affected by heat, prailically non-oxidisable, and
well adapted for receiving finely engraved lines. This
alloy appears to be of all substanc es the least likely to be
affected by lime or cinumstance, and has been preferred
for standards purposes to rock-crystal, gold, i^ic. The
lines on the mitre-ii-lraits are fine, and are barely visible
to the naked eye.

The actual relation of our prototype metre No. if) is as
follows : —

At o C.

No. 16 = I metre - o'6 ^ ± 01 /i at o C.

Here \t. means one micron, or one-thousandth of a
millimetre (or nearly 000004 inch), so that metre 16 may

February 28, 1895]

NA TURE

421

be said to have been verified with an accuracy of one
part in a million.

The certificate of the verification of the end standard,
or iiutre-d-bout (c'talon No. 6), will not be issued by the
Committee until their general conference in September
; but this standard has been verified also with great
accftte-y, with a probable error of ± 03 ^z. In the verifi-
cation of the end standard {inclrc-d-boiit) MM. Cornu
■id lienuit have introduced a method of reflection, by
means of which it is unnecessary to bring the ends of the
metre bai into contact with any touching surfaces, and
thus the measuring ends of the bar may be carefully pre-
served and used. Only Austro-Hungary, Germany,
Great liriiain, and Russia have at present applied
to the International Committee to be supplied with end
standard metres.

Experiments with reference to light-wave analysis,
which have been carried out under the directions of the
International Committee by Dr. Michelson during 1S93,
with the view to the discovery of a radiation of light of
sufficient homogeneity to serve as an ultimate standard of
length, appear to show that it is possible within certain
limits to reproduce the length of the metre by reference
to such physical constant.

The Kilogramme.

The unit of mass of the kilogramme is determined by a
piece of iridio-platinum in the form of a cylinder, the
height and diameter of which are equal (thirty-nine
millimetres). The kilogramme. No. 18, supplied to
Great Britain has no distinguishing marks, and is highly
polished. On analysis it showed very faint traces of
ruthenium, rhodium, and iron. Its volume was found to
be at 0° C.

Prototype 18 = 46'4I4 millilitres,

corresponding to a density of —

2rS454-
After its final adjustment it was found to be in vacuo
at o^ C.

Prototype 18=1 kg. ■\- 0070 ± 0002 milligramme.

So that it may be said that the kilogramme (kg.) has
been verified with a probable accuracy of 0002 parts in
a million.

NOTES.

The Committee of the Athenccum Club, acting under the
Rule which provides for the annual election of persons " of dis-
tinguished eminence in science, literature, the arts, or for
public strvices," have admitted to membership Prof. Bayley
Balfour, F.R.S., and Sir W. H. White, K.C.B., F.R.S.

Dr. F. J. Lauth, the eminent Egyptologist, died at Munich
on the llih inst., at the sge of seventy-three. He w.is
Honorary Professor of Egyptology .it the University of Munich,
and Keeper of the Egyptian Collections. His writings on the
antiquities of Egypt are numerous and important.

We regret to announce the death of Prof Ileinrich Wild, of
St. Petersburg. He was a Swiss by birth, and his work in
magnetism and optics, as well as the magnetometer, polari-
strobometer, and other instruments devised tiy him, are well
known to students of physics.

It is reported from Athens that the architect who has
examined a number of the ancient monuments in Athens, states
that the majority of them, and particularly the Parthenon
and the Temple of Theseus, are in a dangerous state. The
work of rendering them secure would cost a million drachra.is.
The Archsological Society intends to make an appeal to all
countries for a portion of the money required to restore these
wonderful monuments to a sound condition.

NO. 1322, VOL. 5 l]

General Annenkoff, constructor of the Russian Central
Asian Railway, has been appointed one of the vice-presidents
of the International Congress of Geography to be held in
London in July next. Russia will further be represented on
that occasion by nine or ten other well-known men, including
Senator Semenoff (vice-president of ihe Imperial Russian Geo-
graphical Society), M. GrigorielF (secretary of the same
sjciety), and Baron Wrangel (director of the Imperial Lyceum)-

A Reuter telegram from St. Petersburg reports that a
scientific expedition, oiganised by the French Minister of
Public Works, has just arrived at Samarcand. The head of
the expedition is M. Jean Chaflanjon, who has previously made
a journey in South America, and he is accompanied by two
naturalists, MM. Henri Mangine and Louis Gay. From
Samarcand the expedition will proceed to Tashkend, and after
completing all the necessary preparations there, will start on a
journey of exploration in Tibet and other countries.

We are informed by the trustees of the Australian Museum,
Sydney, that Dr. E. P. Ramsay, after twenty years' service as
Curator of this Museum, has retired, owing to ill-health. Dr.
Ramsay's official connection with the Museum as Curator
ceased from December 31, 1894. The trustees have appointed
as his successor Mr. R. Etheridge, jun., formerly of the British
Museum, and lately Palaeontologist to this Museum, and to
the Department of Mines of New South Wales, and who has
on several occasions temporarily acted as Curator. Mr.
Etheridge has entered on the duties of Curator.

Dr. a. R. Willis will commence a course of six lectures
to working men at the Museum of Practical Geology, Jermyn
Street, on Monday, March 4. The subject of the course is
" Heat Engines."

The weather over these islands has been comparatively mild
during the past week, and the higher temperatures which set in
at the end of the prolonged frost were maintained for some
days ; subsequently there was a slight return of cold, with
high barometric pressure, accompanied by strong northeasterly
winds, and snow showers in various places. Fiost occurred on
Sunday and following nights, the lowest shade temperatures
being 27.' in the central parts of Ireland, while in the south-
eastern and midland portions of England the readings were
several degrees below the freezing point.

At a recent meeting of the Vienna Academy of Sciences,
the President announced that the late Herr Joseph Treith,
director of the First Austrian Savings Bank, had be-
queathed the whole of his considerable fortune to the
Academy for the purpose of the advancement of science. The
grants are to be apportioned by a committee of five, three of
whom are to be appointed bv the Academy, and two by the
Minister of -Education, the -Academy to decide all doubtful
questions. The branches of science to be encouraged are those
for which there is no other official provision made. Among
the subjects suggested are the physical structure of the earth
and of the heavenly bodies. The income is to be divided
every year into several grants, but if some great enterprise is to
be undertaken, it shall be permitted to let the funds accumulate
for not more than three years. The extension of higher in-
struction among all classes fitted for it by education, the
strengthening of moral character, the advancement of technical
education, the simplification of medical practice, and the
furtherance of the material prosperity of the human race by
invention and discovery, are the guiding principles indicated
by the donor lor the administration of his generous gift.

At the last meeting of the Socieli.- Franraise de Navigation
Aiirienne, M. de Fonvielle- gave an account of a paper by M.
Andrce, the chief engineer of the Swedish Patent Office, read

42:

NA TURE

[February 28, 1895

on ihe 14th insl. before the Stockholm Academy of Sciences.
In that paper the Swedish aeronaut described a scheme to go
to the North Pole in a balloon, and, to carry out his plans, he
asked for a sum equivalent to about £.'JZ20. Although M.
Fonirielle opposed a similar scheme put forward about seven
years ago by two of his countrymen, he expressed himself
favourable to the new undertaking, and his opinion seemed to
have been shared by the Society. M. Andrile has already
ixectited a number of ascents in very difficult circumstances.
He is well acquainted with all the peculiarities of Arctic
climates, having been one of the meteorologists of the Swedish
I SS2-S3 expedition for observing the transit of Venus from Cape
Thorsden. He hopes to start from this station in (he month of
July, 1S96, as it appears that there are no great variations of
temperature at that time of year. The balloon is to contain
i86,ocx} cubic feet of gas, and Ihe inflation process is to be carried
out at Cape Thorsden by means of compressed hydrogen.

The Select Committee ofthe House of Commons appointed to
inquire into the existing systems of weights and measures in this
country had a meeting on Tuesday, under the presidency of Sir
Henry Roscoe. Evidence was given by Mr. II. J. Chaney, Super-
intendent ofthe Standards Department of the Board of Trade,
who described the system under which the verification of legal
standards is carried on at the Board uf Trade by experts ap-
pointed for the purpose, and also gave an account of the diflferent
systems of weights and measures now in use in the United
Kingdom. He stated that the Imperial and the metric systems
Acre the only ones with which the Department had to do in
England, but there were other local customary weights and
measures in use. There were many weights and measures in
use which were not legally recognised. .■Xmong these he men-
tioned Ihe carat, the boll (used in Scotland), the cU, the coomb
(used for measuring com), the Winchester bushel, the butchers'
stone of S lb., the miners'dish (used for weighing ore in Derby-
shire;, and the gauge (used in measuring plates) as examples of
weights and measures which were not recognised by law. A
number of anomalies which formerly existed — c.f. a ton of
stone being different from a Ion of other materials, &c. — had
disappeared to a great extent under the operation ofthe Weights
and Measures Acts of 1878 and 18S9. The Scotch and Irish mile
were still locally recognised, but for all statutory purposes a
mile was 1760 yards. Practically the only two countries of any
importance in Europe in which the metric system was not
adopted were Great Britain and Russia. In Germany, Austria,
France, Italy, Spain, and Portugal the metric system was the
only system in use.

During recent years the advantages of work at biological
itationi have been recognised at various Universities. The In-
diana Univeriity has lately shown \U appreciation of Ihe need
for such research by deciding upon the establishment of an inland
biological >lalion on one nf the lakes of Northern Indiana,
probably Maxinkuckee. To begin wilh, the main object of the
Station will be Ihe study of variation. I'or this purpose it was
thought that a small lake would present a limited, well circum-
scril il locality, within which the differences of environmental
influences would be reduced to a minimum. The study will
cotiMst in the deleiminationof the extent of variation in the non-
mij;iatory vertebrate*, the kind of variation whether continuous
or discontinuuu;., the quantitative variation, and the direction
of variation. In Ihii way it i^ hoped to survey a base line
which can be utilised in itudying the variation of the same
ipecies throughout their distribution. This study should be
carried on for a scries of ycar>, or at least be repeated at defi-
nite interval! to dcteiminc the annual or periodic variation
from Ihe mean. A compariion of this variation in the same
animalf in other similarly limited and well'ciicumscribe<l areas,

NO. 1322, vor, 51]

and the correlation of the variation of a number of species in
these areas, will demonstrate the influence of the changed en-
vironment, and will be a simple, inexpensive substitute for
much expensive experimental w.ork. In connection with this
study of the developed forms the variation in the development
itself will receive attention; for instance, thevari.ition in segmen-
tation, the frequency of such variation, and the relation of such
variation in the development to the variation in the adult, and
the mechanical causes affecting variation. .-Vdmirable courses
of instruction have been drawn up by Prof Carl II. Eigenmann,
the Director ofthe Station, to lead to thespeci.il investigations,
and there is every indication that useful work will be accom.
plished.

Dr. a. Peter gives, in the Machrichten von der KcniglicheH
Gesellschajt dcr IViisenschaften zii Goltingoi, the results of a
second series of cultural experiments with dormant seeds, taken
from various depths in the soil of woodlands or forest. The
forest in question of the present d.iy is the site of villages and
cultivation that disappeared several centuries ago ; and some of
the samples were taken fro;n dense forest, too to 150 years old,
under the shade of which there has been no surface vegetation
for years. The principal point to investigate was the probable
existence of seeds of cornfield weeds still possessing the power
of germinating and developing into reproductive plants. Dr.
Peters succeeded in raising a large number of plants belonging
to about fifty ditlerent species, including some that are essen-
tially weeds of cultivation ; and he believes he has good grounds
for supposing that the buried seeds of many pasture plants and
cornfield weeds retain the vitality much more than half a
century ; that is, under the conditions he describes.

THEhundiels of Gulls that have lately come up the Thames
in search of food seem only matched by a remarkable invasion
of the north and north-east coasts, by the Little .\uk {Mergiiliit
alle) during January. Writing in the Zoologist, Mr. J. E.
Harling says that on Ihe 21st of that month, great numbers
were observed passing south, both at sea and along the coast,
and many were cast ashore in a helpless condition, exhausted
in their attempts to withstand Ihe stormy weather which has
recently prevailed. In Ihe neighbourhood of Redcar, as many
as two hundred and fifty of these little birds have been counted ;
at .Scarborough they were also numerous, and on the Norfolk
coast one hundred and twenty have been captured, .\nother
result of the severe weaiher and snow during the third week in
January, was that Ihe Grouse in Yorkshiie left Ihe moors in
packs, and migrated to the lower grounds in search of food and
shelter. It is pointed out that an exodus of this kind is of
extremely rare occurrence; the last one being during the severe
winter of 1S86.

In the Mtlcorologisclte Zeitschtift for December last, I'rof.
G. Ilellmann gives a very interesting account of the invention
of the barometer which has now been in use 250 years. Torri-
cclli, who died at the early age of thirty-nine years, was loo
busily engaged in mathematical studies to publish an account
of his discovery, but on June il, 1644, he wrote a description
of it to his friend Ricci. This letter, and Ricci's objections to
Ihe experiment, were published in 1663 by C. Dati, a friend
of Torricclli's, and .is this work is now cxcecilingly scarce,
I'rof Ilellmann has reprinted the correspondence, in Ihe
original Italian, in the above-mentioned journal. Some of the
paragraphs are notewo'^thy, es[iecially those in which Torricelli
stales that il was not merely a (juestion of producing a vacuum,
but of making an instrument which would indicate the changes
ofthe atmosphere. The first continuous barometrical observa-
tions appear to have been made in France. In England they
were first taken by Robert Boyle, about the year 1659, to whom
wc owe the invention of the word " barometer."

February 28, 1895]

NATURE

423

Some time ago we ga»e an account of the considerable

extension of the ultra-violet photographic spectrum obtained
by Dr. Victor Schumann, of Leipzig, by eliminating the air
between the so urce and the sensitive plate, which was found to
€xert a strong absorption upon the rays of shortest wave-length.
This work has been carried on since with great success. At a
recent meeting of the Vienna Academy, Dr. Schumann
announced that he had improved his plates and his " vacuum
spectrograph" so as to obtain results in a few minutes which
used to take as many hours. The hydrogen spectrum shows a
further lengthening, and the spectra of cobalt, iron, aluminium,
zinc, and cadmium have also been considerably extended
beyond 170 ^;U. This limit, although far beyond the ordinary
limits of the photographic spectrum, was due to a residue of
air and electrode vapour. The absorptive effect of air upon
the most refrangible rays was traced down to thicknesses below
O'Ol mm. Hydrogen also shows a strong absorption for these
extreme rays, especially if insufficiently dried.

Herr K. Mack, working in the Hohenheim Physical Insti-
tute, has succeeded in demonstrating the occurrence of double
refraction of electric waves in wood. That electric waves, un-
like light waves, are capable of penetrating wood, was already
found by Hertz. " It is not without surprise," he says in his
classical work on the "Propagation of Electric Force," "that
one sees the sparks appear inside a closed room." But the
fact that waves of electric force are transmittc<l in a different
manner accordingly as they vibrate across or along the fibre of
the wood, has only just been proved by Herr Mack, who gives
a full description of his method in the current number of
IVieil'.manits Aittialen. It is well known that two NicoU
prisms transmit no light when their principal planes are crossed,
but that light may be made to appear by inserting a doubly-
refracting substance between them. For the Nicoll prismssub-
stitute Hertzian concave mirrors with their focal lines crossed,
and, instead of the tourmaline or other doubly-refr.iciing sub-
stance, insert a plate of wood 10 inches thick, with its fibre at
45° to each of the focal lines, and you have Mack's apparatus.
The sparks, which are extinguished on crossing the two focal
lines, reappear on inserting the wood in the manner indicated.
This striking experiment form; another important link in the
chain connecting the domain of light with that of electiicity.

IfJ an admirable paper on the after-shocks of earthquakes
lyournal of the College of Science, Imperial University of
Japan, vjI. vii. part ii.), Mr. F, Omori has attacked a some-
what neglected branch of seismology. In three recent
Japanese earthquakes, those of Kumamoto in 1S89, Mino-
Owari in 1891, and Kagoshima in 1893, the after-shocks have
been carefully recorded, and are here specially studied from the
frequency point of view. Numerous tables are given, and also
many curves showing the way in which the number of after-
shocks varies with the time at different places. When their
inequalities are smoothed away, these curves differ little from
rectangular hyperbolas. At the same time, they show periodic
6uctuations in the decrease of frequency of after-shocks. Be-
sides the diurnal and annual fluctuations, six different periods
have been ascertained, whose lengths range from a few hours to
several months. In the case of the great Mino-Owari earth-
quake of 1891, the after-shocks were most numerous some dis-
tance to the south of the principal epicentral tract, which lay
in the Neo valley. They also occurred more frequently along
four axial lines, r.adiatinj from the vicinity of KoDri, th.an in
the neighbouring districts. Mr. Omori suggests that the
principal earthquake was caused by the formation of some great
fractures beneath the Neo valley, and that the axial lines
indicate the positions of four weaker or deeper fractures, along
which the crust is not yet in the way of steadily settling into
equilibrium.

NO. 1322, VOL. 51]

In a paper recently published {fournal of Geology, May-
June 1894 ; Johns Hopkins University Circular, January
1895), Prof. W. K. Brooks discusses from the zoological point
of view a problem familiar to the geologist — the sudden appear-
ance in the Lower Cambrian of a rich fauna in which most of
the great classes of animals are represented by unmistakable
forms. His conclusion is that early Cambrian times and those
immediately preceding them formed a period of rapid modifi-
cation induced by the first colonisation of the sea-bottom. His
arguments maybe briefly summarised thus : — Embryology indi-
cates simple pelagic forms, as the ancestors of all the great
animal stems. The existing pelagic fauna consists in part of
small and primitive forms, and in part of the specialised de-
scendants of shore or bottom forms. The fact that the latter
are almost exclusively carnivorous indicates the enormous
wealth of plant-life, mostly of minute forms, on which ulti-
mately the existence of all the fauna depends, and shows the
extremely favourable character of the conditions of pelagic life
to simpleorganisms. The supply of these simple organisms is in-
exhaustible, and on themthe bottom-fauna also depends for food.
It is suggested that the evolution of all the main stems of animal
life took place at tlie surface of the ocean, but that when their
descendants had colonised the bottom the crowding that soon
ensued there led to fierce competition, especially between nearly
related forms, and to the specialisation of the types already
established, but not the production of new types. Tfie develop-
ment of hard skeletons was an early result of these conditions.
Geologists will certainly find many points to criticise in Prof.
Brooks's sug'^estions, but they constitute an important addition
to the discussion of faunal origins.

One of the many botanic stations the advancement of which
has been promoted by the Director of the Royal Gardens at
Ke«-, is that at Aburi on the Gold Coast. A few interesiing
facts referring to the est.-iblishment and present condition of this
station are given in the Keiv Bulletin for January, from
which the following information has been gathered. The site
is in the hills, .-it an elevation of about 1400 feet, overlooking
the sea-board, near Accra and Pram Pram. In addition to its
suitability for the growth of economic plants, Aburi is a valuable
resort for European invalids. The locality has been greatly
improved of late years, and it promises to become the centre of
activity for many cultural industries started by the Botanic
St.^.tion. During the winttr of 1893-94 Mr. William Crowther,
the curator (appointed in 1S90), was deputed to visit the West
Indies "to observe the system pursued there in the cultivation
of economic plants, and to bring back such useful seeds and
plants as might with advantage be introduced to the Gold
Coast." Mr. Crowther very successfully carried out the object
of his mission, and published a delaileil report. Since then the
work of the .Vburi Station has made excellent prepress. The in-
ception, as well as the actual work, so far accumplished in
botanical enterprise at the Gold Co.ist, is entirely due to the
Governor, Sir W. 1!. Griffith. He has given warm .and con-
sistent support to the station, and personally encouraged in
every vv.ay the efforls of the cur.ator.

The Forsckungsherichte ( Theil .3, 1895^ of the biological
station at Pliin, recently published, contains a number of
interesting papers on the flora and fauna and on the biological
phenomena of ihe lakes adjoining the station. Among the
contents may be mentioned the copious reports on the flora by
Drs. Klebahn and Lemmermann, the faunistic contributions of
Dr. Zacharias, and the memoirs of Drs. iiacharias and
Strodtmann on the Plankton of the lakes. The investigation
of the movements, periodicity, and changing quantity of
floating organisms in inland- waters can be pursued with such
ease and completeness, as compared with marine phenomena.

424

NATURE

[February 2S, 1895

that biologists miy look forward to the early achievement of
valuable results by Dr. Zacharias and his assislanls. The
present report goes far to justify this expectation.

The history of the Royal Microscopical Society, as told by
Mr. A. D. Michael in his presidential address last month, is
contained in the February /ciirnal of the Society.

A BOOK of gummed labels, for the chemical laboratory,
having the names of 750 special reagents, &c., printed upon
them, has been compiled by Mr. \V. H. Synions, and published
by Messrs. A. Gallenkamp and Co.

We are always glad to see the Reports of the Natural Science
Societies of our Public Schools. The twenty-fifth annual re-
port of the Wellington College Society has ju>t come to hand,
and the abstracts of the lectures delivered under the auspices of
the Society, as well as the records of observ.itions in various
branches of science, show thai excellent work is being done in
creating and fostering interest in natural knowledge.

Mr. H. Warinxton Smyth's I"Notes of a Journey on the
Upper Mekong, Siam," read before the Royal Geographical
Society just a year ago, have been published in a handy .ind
attractive form, for the Society, by Mr, John Murray. Siamese
and Laos life are vividly described in the volume, and interesting
information is given with regard to the geographical and general
features of the country traversed.

The Society for the Protection of Birds was called into
existence to protest against the slaughter of birds for decorative
purposes. It now numbers more than eleven thousand members,
and the fourth annual report shows that it plays an important
part in preventing the extermination of our rarer species of
birds. Owing to the Society's efforts, that remnant of primitive
ornamentation — the bird-wearing fashion — is on the decline.
The Bill passed last July, to amend the Wild Birds' Protection
.\ct of 1S80, is given at length in an appendix to the report.

.■\ HANDY work of reference, occupying an intermediate
position between a mere school dictionary and a bulky lexicon,
is Ogilvie's "Student's English Dictionary," a new edition of
which, edited by Dr. C. Annandale, has been published by
Messrs. Blackie and Son. The new is.uc has been so greatly
changed and augmented, that it is practically a fresh work. A
large number of scientific and technical terms, many of them
recently introduced, as well as thousands of other woid;, have
been added. The woodcut illustrations have been more than
doubled, there being now nearly eight hundred of them.
Experience has taught us that the " Students' Dictionary " rarely
dbappoinO the inquirer ; in its improved and enlarged form, it
will be even more useful.

Messrs. Macmii.lan and Co. will shortly publish an im-
portant work on " Meteorology," by Mr. T. Russell. The
book ha* for its main object the explanation of the use of
wcathcr-mapi for the purpose of making forecasts. The variou?
forms of meteorological instruments .tre described, and a general
view il taken of all knowledge connected wiih the science of
meteorology, and of interest in relation to weather changes. To
a large extent, the volume refers to weather prediction in the
United .Stales, and to the use of wcnther-ma|is in the prediction
of I1oo:l> along I he lower Ohio and Mississippi Rivers. It will, how-
ever, alio appeal to European meleorologi«ls, as well as assist in
the development of scientific weather ubscrvation and predic-
ion. Another work which will very soon be published by the
same firm, it a translation of the late Prof. A. dc Qualrefages'
NO. 1322, VOL. 51]

" Les Pygmces." This volume, which is the second in the
Anthropological Series, has been tr.inslaled by the editor of the
series. Prof. F. Slarr, of the University of Chicago.

The atomic weight of tungsten has been subjected to a
careful revision by Prof. E.F. Smith, of the Pennsylvania Uni-
versity, and the specific heat of the pure metal again determined.
Two independent series of atomic weight determinations have
been carried out, in which Prof. .Sinilh has been assisted, re-
spectively, by Miss M. E. Pennington and Mr. E. D. Desi, and
accounts of the work are contributed to the current issue of the
Ztilschri/t fiir Anorganische Chemie. In the first series the
method employed consisted in the reduction of pure tungstic
acid to metal in a stream of pure hydrogen, and then deter-
mining the amount of oxygen absorbed by the metal upon con-
version of the latter into tungstic anhydride by ignition in con-
tact with the air. The mean value of the atomic weight derived
from nine such determinations, taking oxygen as 16, is iS4'92.
The highest and lowest values obtained differed by only 002
from this mean value. The second series of determinations
were based upon the estimation of the amount of water pro-
duced during the reduction of tungs.ic acid by hydrogen.
Exceptional precautions were taken with the purification of the
latter, in order to exclude error from this source. The mean of
six experiments affords the value 184 '"o for the atomic weight
of tungsten, the greatest difference between the individual
values being only 007. The slight difference of o"2 between
the results derived from the two methods of work is probably
to be ascribed partly to the difference in the methods, and
partly to the different personal factors involved. The mean of
the two series, iS4'8, may therefore be taken as representing
a close approximation to the true atomic weight of tungsten.
This value is considerably higher than the currently accepted
one, 184 02, the number afforded by Clarke and Becker's re-
calculation of the experimental results of older determinations.
The increase is in all probability due to the great pains which
have been taken to remove the last traces of the lighter molyb-
denum from the tungstic acid employed, a task which is par-
ticularly difficult, and which most likely has never previously
been so completely achieved.

The specific heat of the pure tungsten obtained during
the course of the atomic weight determinations has been ascer-
tained by Prof. Smith in conjunction with Mr. Gioilspeed
The method adopted was that described by Joly in 18S6, in-
volving the use of the "gravimetric calorimeter." The final
mean value arrived at for the specific heat of tungsten
o'033S, a result closely agreeing with former determinations 0
this constant. The atomic heal obtained by multiplying the
new value for the atomic weight by this number ex|)ressing the
specific heat is 6'25, a value in f.iirly close accordance with that
usually accepted as representiuL; the constant ol Dulong and
Petit for the truly metallic elements.

The additions to the Zoological Society's Gardens during the
past week include a Lion (/v/iV/tv, i ) from India, presented by
Iler Majesty the <Jucen ; a Black-striped Wallaby {Ihiltiitilurus
(iorsalis, i) from New South Wales, presented by Miss 11. W.
Howes; a Hairy-rumped Agouti (/>asyfiroclti prymnoLipha
from Guiana, presented by Miss W. B. Jackson ; a Ros-ite
Cockatoo (C(Jfa/KiJ roscicopilla) from Australia, prcsenir Ny
Mr. A. Reynart ; four Triangular-spotted Pigeons (Coliinilm
guinea), two spoiled Eigle Owls (/lii/w ma ulosa) from .South
Africa, presented by Mr. J. E. Malcham ; a I'ieUlfare (Titrdiis
pilaris) British, presented by Mr. (lervasc !•'. Mathew ; two
Lions (/■ir/ij Ico, i 9 ) from India, deposited ; an Eland {Oreas
canna, 9), two Collared Fruit liats (Cynonycltris coltaris)
born in the Gardens.

February 28, 1895]

NATURE

425

OUR ASTRONOMICAL COLUMN.

Origin of the I,unar Formations. — The experiments by
which Scrope altempted to reproduce the characteristic features
of the moon's surface have been repeated with slight modifica-
tions by M. .Stani>las Meunier, and the results which he has
obtained are certainly very suggestive, if, indeed, they do not
furnish the l<ey to the origin of the various formations which
the moon presents tD us. (C(?OT//^y ^-j^wi/r/.?, January 2S.) Plaster
is mixed with water in which a little glue has Deen dissolved to
prevent too rapid setting, and the mixture is heated in a frying-
pan over a gas-burner until ebullition commences ; the gas is
suddenly turned off at an opportune moment, and the mass is
left to cool undisturbed. Experimenting in this way, and by
varying the consistency of the paste, M. Meunier has obtained
many features besides the intermingling circular cavities pro-
duced by Scrope. The central peaks which are so frequently
noticed in lunar craters are reproduced perfectly, being formed
at exactly the same time as the circular borders, and even
resembling their lunar prototypes iu being generally somewhat
lower than the edges of the craters. Further, the artificial
craters tend to form in groups of two or three, or even more,
and sometimes one ring will envelope several ; some parts may
be covered with cavities, with or without central peaks, and
relatively large smooth areas at once recall the lunar "seas."
If the experiment be carried on until nearly the whole of the
water is evaporated, fissure^ also make their appearance.

13y covering the paste with fine grey sand at the moment it
begins to boil, the results are said to be still more striking, and
better adapted for photography.

M. Meunier expresses the opinion that the moon has failed
to pass through all the planetary stages, in consequence of the
original relative scarcity of fluids, and he believes this concep-
tion to be confirmed to some extent by another modification of
the experiment, in which the paste is covered with a rather
thick layer ol sanii, representing the rocks forming the
earth's epidermis ; the "volcanic" manifestations then change
character, and more nearly approach terrestrial types.

7 Cassiopei.f.. — This star has always possessed a special
interest to spectroscopic observers since the discovery of bright
lines in itsspeclrum by Secchi. Continued observations seemed
to suggest a periodicity in the visibility of the bright lines, but
this question can now be attacked more completely by the
photographic method. Fifty-three photographs, extending
over a peiiod ol six years, have been taken at South Kensing-
ton, and a first examination of the negatives has led
to several important conclusions {Roy. Soc. Proc. vol. Ivii.
p. 173). The lines of hydrogen were constantly bright in
the period covered by the ph(.tographs, and other bright lines
were also seen in all good photographs. Further, the lines of
hydrogen are double in all the photographs taken with su.licient
dispersion, and the distance between the components is constant
within the limits of error in measurement. Other conclusions
are that the bright lines of hydrogtn are superposed on broad
dark bands, and that there are also other ill-defined dark lines
in various parts of the spectrum ; these dark lines correspond
very closely with the lines seen in the spectra of (,'Orionis and
Itellatrix. *' This at once contradicts Prof. -Scheiner's recent
statement that he does not believe it possible that dark lines can
exist in the s[)ectrum." Dark lines have also been observed
and photogra[)hed by Keeler.

It will be seen that the spectrum presents numerous peculiari-
ties, and an explanation of the physical condition of the star or
stars winch produce the different appearances is by no means
simple.

The Identity ok Denninc's and Brorsen's Comets. —
It was pointed out in the Ailronomisthe NaehrichUn, No. 3271,
that the orbits of the comet 1894 I (Denning), and Brorsen's
comet, intersect in heliocentric longitude 285°, and that eaily
in l88l the two objects must have been close to one another
near the point of intersection (see Nature, January 24,
p. y>2). The elements used for the cgmparison were, in
the case of Denning's comet, due to M. Schulhof.
This computor gives new elements for the comet, in
Aslr. Nachr. No. 3276, and expresses an opinion
upon the suggested connection. He thinks that the
elements compaied, with the exception of inclination, certainly
present some points of resemblance. More important, per-
haps, is the fact that the point of intersection of the two orbits
is nearly their point of nearest apjiroach to the orbit of Jupiter.

NO. 1322, VOL. 51]

A'

Applying M. Tisserand's criterion for the connection between
two orbits, the value 0'47 was found for Brorsen's comet, and
©•50 for Denning's. It is therefore concluded that the
two comets formed at one time a single body, and that after
their separation their orbits were more and more modified by
Jupiter.

THE ANTITOXIC SERUM TREATMENT OF
DIPHTHERIA}

If.

The Treatment.

SSUMINGnow that the antitoxic serum is available, how is
it to be used? It has been strongly recommended that it
should be used not only as a curative or direct therapeutic agent,
but that it should also be used as a prophylactic — that is, as a
protective agent against possible infection, especially during
those periods when diphtheria is rife. It is almost too soon to
consider this prophylactic property of antitoxic serum, as for
some time to come the energy of those engaged in the prepara-
tion and use of this serum must be directed towards obtaining
a sufficient supply for the treatment of cases of developed
diphtheria.

Results of this Method of Treatment.

It may be well to consider what have been the results obtained
up to the present, and for this purpose the statistical method
will probably carry most conviction, especially if it is possible
to give full and accurate detail ; and now that these statistics
have been criticised not only by those who have used this treat-
ment, but also by those who oppose it because it runs counter
to their feelings and ideas, they are every day more and more
trustworthy, much fuller, and more valuable.

It is first necessary to determine the average case mortality
in diphtheria for some considerable period before the antitoxic
treatment was introduced ; then to see what has been the lowest
case mortality during an ecjual and similar period for which we
have any statistics ; and lastly, to compare these with the case
mortality of the period during which the antitoxic serum has
been used.

In Table I. are given the mean annual death rates from
diphtheria per million living in England and Wales and in
London, in four periods of three years each.

Table I.

i83i-3 1884-6 1887-9 1891H

England and Wales ... 144 ... l66 ... 173 ... 192
London 21.^ ... 227 ... 315 ... 377

Dr. Sykes gives the following statistics t^ — During the year
1892 there were 1962 deaths from diphtheria in London, whilst
in 1S93 there were 3265, or neatly twice as many deaths.

Now let us see what has lieen the case mortality. Statistics
after correction give the following results. During 1893 there
were 13,694 cases of diphtheria notified in London. The
mortality amongst these cases was 3195 (Lancet statistics
correcied), or 233 per cent.

Table II. gives further information, and enables us to see what
is the diphtheria case mortality in large well-found hospitals.

TAni.ElI. — Metropolitan Asylums Hoard : Admissions and Case
Mortaliiy, Diphtheria, 1888-93.

1888 ... .

1889 ...

1890

1891

1892

1893

Note. — Diphtheria cases have only been admitted into the
Hospitals since October 23, 188S.

In Table III. are given statistics dealing with the diphtheria
case mortality where the serum treatment has been used.
Wherever possible, the case mortality over a considerable
period is given in the last column of the table, for purposes of
comparison.

' A lecture delivered at the Royal Institution, on Friday, February 8
by Dr. G. Sims Woodhcad. (Coniinued from page 406.)

No. of

No. of

Per

centage of

.'idmissions.

deaths.

case mortality.

99

46

464

722

27s

38-0

942

3i6

33-5

1312

397

302

2009

583

29 0

2848

865

303

426

NA TURE

[Februakv 28, 1895

Table III.

1 i

!i

^

0

!',

0

« >.

•0

?;•=

-

es

P

2~

%\

3

==

Germany, Austria, Holland :-
Ko5>el (up to May

1S94)
Kossel (March 15-
Drcember i,

1894)

Bokai

Heubner...

KaU

'Aronson . .

Korte

Ranke
•Weibgen .

Borger ...

Knntzen

Hager

Moller

Sonnenbur);
'Bacnisky (quoteil
by Virchow) ..
•Hahn

Wiederhofer

Schiller

Strahltnann

Rumpf ..

blumcnfeld

Heim

Orandinger

Monli

Unlerholzner
Ganghofner
Olhcr observci.i

Berlin

Buda-Pesth
Berlin

!," &c.

Munich

Berlin

Greifswald

Oscher leben

Magdeburg
Berlin

Vienna
Trieste

Hamburg
.\ustria
Vienna

Prague

54 230

117 >3

35 5

96 37

128 17

255
121

'9
65
30
25
25
76
107

303

205

100

252
32 none

100 ,,
26

50 2
27 6
27 II
25 I

3- 8
no, 14

39 4

49
24
45

France, Italy, Belgium, Switzerland.
Roux, Martin, ai d

Paris

Chaillou
Moizard ...
Lebrelon...

Rabot

Mya

M assei
Charon . .

Seitz

America :—
Whit-

Muehlcck

Welch ...

Catlin

Great Britain

Cases reported in
the I.aiuel and
liriliih MeJi<al

y I'll) nal

Washbourn,ijoo<l-
all, and Card

Lyons

Florence

Naples

Belgium

Constance

448:109

23' 34
242 28

47
17

16

2
none

'3l 4

271 I

New York 321 8

riiiladelphia
Baltimore

123 22

'4

17

u = -

2.2-3

14 2

385
13-2
I2-I

33'

21 o

280

6-6

12

4

39-6

20 6

'32
24
24

■7-8
00
00
80
40

222
407

4
2S-8
12 7

10-2

24 5
14.7
IIS

34"
II 7

00
307

37

25 'o

, 34 7

53S
62-5
38 9
32-5-41
53-8
49 2
40 o
20

55-6
27 '6

478
40 o
526
438

120

380
525

66 6
49

517
50 o '

50 o

I 427

( Two not
I ' Heated

( died

Average

for

London

23'3

Average

for
Hospital
194 388

It ii ohjecled, however, ihat general statistics of this kind are
of comparatively little vahic unless the age of the patient
irtaied is given. In order to determine the foundation upon
which this certainly very Icgilimale objection is based, I have

* Thtre it piMl>aI.lv ftimc over)ap|nng, e»r>ccially in ihc Rerlin rietlrc.t.
ItiU fftCt must l>c ukcn into account in rlcalina ^s-ilh this tabic a« a whole.

NO. 1322, VOL. si]

taken four series of cases as reported, and have placed them
>ide by side. The percentages of deaths at certain ages in the
London Asylums Boaid hospitals before the serum treatment
are given in Table IV., the percentages of deaihs of four
observers who have used the serum, in Tables V. and VI.

Table IV. — Showing the Mortality at Various Ages Jrom

Diphtheria admitted into the Metropolitan Asylums

Roarifs Hospitals in the years 1888-93.

I'a^ts

.idmttttd.

Died.

Mortality per
cent.

L'nder 1

1 to 2

2 to 3 .

3104 •
4 to 5 .

Totals under 5 ..

S to 10..
10 10 \t,..

146

102

699

447

291

651

639

388

(07

826

416

504

9"3

400

43S

2971

2462

SS5

1597

705

93

53 8

2S 6
10 ;

Table V.
Skouiin« Mortality from Diphtheria r.t various Ages.

Kossel

Wie

•0

derh<

)fer.

Goodal).

Tot.il

T3

•6

i

"6

-D

ft>

■a

•^

■0 X

Q

I

5

u

s

■I

V

n

0 l.s

H

33'3

S

s

a<

H

4

B.

Under i year...

3

I

6>-5

I

350

•5

7 .46-6

I 3 years... _

4

0

O'C

»4

9

37'S

10

3

30'0

3"

II 38v<

=-3 1

18

3

1 1*1

ao

7

VS'o

7 i '

143

45

10 13'2

34 ..

14

3

31 4

•4

0

00

9 3

333

37

6 l6'3

4-5

33

59
45

3
9
1

■5'5
15-3

16

S3

3

187

10 5

50 0

46

It

339

Total under s.-

»4

0

29-2
o'o

40 13

300
9'

181

45

5

J4'3

5-10 years ...

6-6 1 15

33

2

83

6-0

>o-is

■3'
..7

1
■3

77I 3

0

=4

o"o

10

7J

0

00
■9 4

3b

'

3t

Grand toials ...

■■•■

.00

94

289

51

'"'•'

I None of these were more than 13 years of age.
Taiii.k VI.
Baginsiy (ijiioted by Virehoxv).

Wiihouc serum treatment.

With serum treatment.

Tieated. Died. Per cent.] Treated. Died. IPcrLcnt.

o-2yeais..

2-4 .. •

4-6 ,. .

6-8 „ .

8-10 ,,

10-12 ,, .
12-14 ..

33

23

56

37

50

27

44

15

24

7

'4

I

9

0

230

no

697
661

540

341
292

7'

00

478

34
S2
81
46

30
18

303

40

23s
195

8 6
10 9
100

00

It isvery impiirlant, however, lhat the period of the disease at
which the treatment 'is commenced should be taken into account,
for, as already indicated, experience has taught that I lie later
the stages of the disease at which this serum is injected, Ihc
stronger must be the dose given. It is necessary, therefore, to
separate the cases in which the treatment is commenced at an
early period from those in which it is commenced only when
the poison has had time to disorganise the tissues, and to rentier
them iiicnpable o( rending to the antitoxic serum.

February 28, 1895J

NATURE

427

The following table (VII.), given by Kossel, brings out the
great importance of this element in keeping down the case
mortali'y. In ihe first column is given the day of the illness
on which antitoxic serum was first injected : —

Table VII.

Day of illness.

Treated. Died.

Percentage

I.

14 ... 0

00

n.

30 I

3-3

III.

29 . . 0

00

IV.

9 ■ ■ ■

II-I

V.

II ... 2

i8-i

VI.

6 ... 3

500

VII.

5 ... 2

400

VIII.

6 .. 2

333

IX.

I ... I

loo-o

jnknown

6 ... I

166

117 13 ... Ill

I'"or statistical purposes, too, only those cases which have
been bacteriologically examined and found to be due to the
action of LocfHer's diphtheria bacillus should be accepted as
being cases of true diphtheria. As most of the cases in which
ihe diphtheria bacilli are absent run a much milder course, and
.ire much more amenable to general treatment, and as many of
these have been included under diphtheria in the old statistics,
such elimination will necessarily make the record X'W rather
against the antitoxic serum treatment than in its favour.

I'rom a somewhat extended experience (although condensed
into a very short period of time) I am satisfied that this question
of the Loeffler bacillus is most important, and that every case
in which the serum is used should be bacteriologically
examined.

It has been said, however, and said very truly, that statistics
may be made to prove anything, and I have heard it said that
the observation of a few cases of diphtheria under the antitoxic
treatment is worth all the statistics that could be brought
together for convincing a man of the value of the antitoxic
serum treatment.

A distinguished physician, who has had charge of diphtheria
wards for some time, informs me that the patients he sees now
wear an entirely different aspect from those he saw before the
serum treatment was adopted. Instead of being struck by the
stupor,tbe pain, the difficulty of breathing, and the other distress-
ing symptoms that so frequently manifest themselves during the
lourse of this treacherous di-ease, he observes children with
patches of membrane in the throat sitting up and playing with
their toys. There is little of that distress of breathing, very
little of the anxious look, and the wards altogether present a
much more pleasant and genial appearance than he has ever
litfore noticed. The other day I received a short note from
another colleague, whohasbeengoingover the German hospitals
!n study this question, in view of taking out with liim to the
colonies a supply of antitoxic serum ; he al-o stales that this
difference in the appearance of the diphtheria wards has im-
pressed him far more than any statistics he has yet come across.

The alleged Ill-effects of the Use of the Serum.

It has been said that most unfavourable symptoms have
followed the exhibition of this serum. Theiccan be nodoubt of
the fact ; but alter a careful study of the cases repotted, I am
thoroughly convinced that a very large proportioniof them, at any
rate, are merely post hoc ^ and xiQi propter hoc. There can be no
doubt that a kind of nettle-rash makes its appearance during the
course of treatment, and that this may be accompanied by pains
in the joints. Both these conditions, however, are usually quite
transient, and seldom give rise to permanent ill effects.
Albuminuria has also been ascrilied to this treatment; but any
one who has had to deal with children not only suffering from
diphtheria, but from any form of disease, and even from none at
all, will bear witness that albuminuria in children is of compara-
lively frequent occurrence. It is not striking, therefore, that
1 hose who have hitherto paid little attention to this subject should,
v.hen they come to make a careful examination of children af-
fected with diphtheria, find a considerable number of cases in
which transient albuminuria is a prominent symptom. More
than this, however, it has been my duty to examine a large num-
ber of cases in which diphtheria has proved fatal, and in these
cases there were certain lesions in the kidney, so distinct and so

NO. 1322, VOlv. 51]

frequently present, that in describing Ihem I used to note simply
"diphtheritic condition," and then describe in detail only
those features in which the appearances differed from the type
that I had in my mind. This will indicate to you that altera-
tions in the internal organs, especially in the kidneys, such as
would lead to marked interference with the performance of their
proper functions, were present, and had been noted long before
the antitoxic serum method of treatment came into use. I may
give an example of what, under ceriain circumstances, might have
been used as a powerful argument against the use of aniitoxic
serum. In the Deiiliche Medizinischer Wochemchrift for
December 20 of last year is reported a case of acute haemorrhagic
nephritis coming on after the use of Bchring's curative serum.
The patient recovered. But a similar case of acute hasmorrhagic
nephritis in diphiheria, in which, however, the curative serum
was not used, is reported in the same number of the same journal.
The author of the second paper quotes some interesting statistics
to show that albuminuria is of frequent occurrence in cases of
diphtheria not treated with aniitoxic serum. One observer found
it in 131 out of 279 cases ; anoiher in i6 out of 53 ; another in 60
per cent, of all his cases ; anoiher in 227 out of 470. Sup-
pression of urine has also been ascribed to the action of this
agent ; but here again, if a careful search be made of the records
of diphtheria cases treated under the old method, it will be
found that just as in scarlatina and acute specific infective dis-
eases generally, but especially in those associated with rapidly
supervening toxic symptoms, suppression of the urine is of
common occurrence; and until we have statistics on these
several points, which can be compared with those above men-
tioned, it will be impossible and unjust to ascribe conditions to
the therapeutic agent which, so far as those best able to judge
can see, are to be ascribed to the disease itself.

It has been held t>y some that the paralysis which is
so common a sequel of diphtheria should disappear entirely
under the use of what they are pleased to call a specific cure for
the disease. It should be remembered that the antitoxic serum
cannot make good any organic damage that has been caused by
the action of the toxic products of the diphthuria bacillus. It
may stop their action on the tissues, and it may stimulate the
tissues to react against the poison, but to the tissues themselves
must be left the process of repair ; the rvi mcdicatrix natiira: is
alone responsible for the making good of damage already done.
This damage may be done at a very early stage of the disease,
and if the nerves or the muscles are attacked before the anti-
to.xine is injected, then we must expect to find degenerations and
evidence of these degenerations in the various forms of post-
diphtheritic paralysis ; but of this we may be sure, the sooner
the poison is antagonised ihe less will be the risk of permanent
damage to the tissues. It is for this reason, I believe, that the
antitoxic serum treatment of diphtheria has been so much more
successful than the antitoxic serum treatment of tetanus.

Conclusion.

The hope of success in diphtheria depends upon the early
application of the remedy. One word of warning. It .should
not be accepted that this agent can reduce the cure of diphtheria
to a mere process of injection. Everything must be done to
improve the conditions under which the patients are treated, to
maintain their strength, to give them fresh air, cleanly
surroundings and good general hygienic conditions. It
will be found withal that a certain number of deaths from
rapid poisoning will take place, while a number of others will
succumb in the later stages of the disease. This scrum can no
more act as a specific in every case than can quinine cure every
case of malaria; but if properly used, we believe it will reduce
the mortality in a very marked degree, and if at the same time
those practical sanitary reforms and improvements for which
our country is so justly renowned are carried out, «e may expect
that diphtheria as a scourge may gradually die out from our midst.
.•\s Dr. Seaton pointed out at Buda-Pcsth, we have done more
in this country to improve the conditions associated with most
specific infective diseases than any other nation in the world.
If, now, we can graft on to our system what is best in Behring's
treatment, I am convinced that we shall soon have diphiheria
statistics which will compare very favourably » iih any that have
yet been presented. The antitoxic serum treatment is only
one of our lines of defence against this disease ; but so much
progress htis already been made along this line, that within a.
few years, or even months, We may fairly anticipate the an-
nouncement of still greater advances and successes.

428

NA TURE

[February 28, 1895

DR. DUBOIS' SO-CALLED MISSING LINK?

A T » meeting of the Roval Dublin Society, held on
■^ Wedneslay, Januar)' 23, Dr. D.J. Cunningham, F. R. S.,
Professor of Anatomy in the Univeisiiy of Diulin, .ind Hon.
Secretary of the Society, read a paper upon the characters
presented by the fossil remains recently de-cribed by Dr.
Eugene Dubois. (See Nature, January 24, p. 291.) The
following is an abstract of ihis communication.

The fossil remains are three in number, viz. : the upper part
of a cranium, a right-upper wisdom looih, and a left femur.
These are believed to belong to the I'leistocene period,
and, according to Dubois, present characters which justify him
in placing the animal to which they belonged in a new family
which s'aiids midway between man and the apes. The speci-
mens were found in Java, on the left bank of the Bengawan
River, i'l the neighbourhood of Trinil. Each was exhumed
at a different time, but all at the same level, viz. 1 m. below
the dry-season level of the river, and from 12 to 15 m.
below the level of the plain through which the stream has cut
its way.

The characters assigned to the new family proposed by
Dubois are the following : " Cranium absolutely and rela-
tively to boiy-size, much more roomy than in simiida;, but les-
roomy thanin hominida?; cranial capacity about two-thirds of the
average capacity of the human cranium. The inclinalion of the
cervical surface of the occiput distinctly stronger ihan in simiidae.
Dentition after the type of the simiiHa:. Femur similar in its
dimensions to that of man, and designed for the upright walk
and attitude."

The leading peculiarities of the cranium of the so-called
Pithecanthropus are : (1) the low depressed character of the
cranial arch ; (2) the extreme narrowness of the frontal region ;

Fic. i.-ri
of a
* Ik
external •
front.

■' :.- cr.-inial .-irch of: <i, ordinary Irish siciill ; ^, skull

idiot ; c, the fossil cranium described by Dubois;

I. The base-line i< one which passes throuRh the

il'iMl fTotulKnince behind, and the centre of the glabcll.i in

and (3) the striking development of the superciliary ridges.
These are all to sodc extent simian fcitures : and when out-
linei of the aniero-postcrior cranial arch of an ordinary Irish
■kull, of the skull of a microcephalic idiot (the brain of which
presented many atavistic characters), of the fossil cranium, and
of the skull of a young female gorilla, are reduced to the same
size and superimposed over each other, it is seen lliat ilie idiot
cranium and the fossil cranium procnt almost identically the
same curvature ; further, these two outlines occupy a place
almost exactly midway bctwcccn the Irish cranial outline and
that of the gorilla. (Fig. I.)

Another combination, equally interesting and equally in-
stnic ive, is one in which the outlines of the anteio-postcrior
cranial a'Ch of the fossil form, of tiic Neanderthal skull, of the
Spy cranium No. 2, and of the ordinary Irish skull, arc super-
imposed over each other. {Fig 2.) In this the Neanderthal
arch is seen to preserit almost exactly 'he same ch.iractcrs as those
of the fossil form, anrl, lurihcr, lolienrarcrloit than to the outline
of the arcli of the modern Iri-h skull. The .Spy cranium N>,. 2
lakes its place between the normal skull anil the Neanderthal
cranium, so that by a sctiei of easy and nearly equal gradations

> " Pithecanthropus erecluf, eint mcnschaenlictie UherganKsrorm aus
Java." By Kiigenc Dutwis, (Batavia, 1894.)

NO. 1322, VOL. 5[]

we are led from the fossil form up through the Neanderthal and
Spv forms to the modem cranial arch.

The heavy, strongly marked superciliary ridges constitute
another Ne.inderthal.id (eaiure of the fossil loriu, but the trans-
verse frontal diameter is very much less than that of the
Neanderthal or Spy crania. In this rtspect the fossil cranium
closely approaches the microcephalic skull referred to above,
and also the skull of the gorilla.

When the measurements of the fossil cranium are compared
with those of the Neanderthal and Spy skulls, other striking
resemblances become manifest.

-

Maximum
antero-
posterior
diameter.

Maximum
Iran-verse
diameter.

Cepha-
lic
index.

Cranial
cap.-icity

Fossil cranium

1 85

130

70

I00O(?)

Neanderthal cranium ...

200

■44

72

I200(?)

Spy cranium No. I

200

140

70

—

Cranium of intelligent

adult Homan measured

in the .\nthropometric

Laboratory of Trinity
College

167

«39

832

—

The fossil cranium is thus only 15 m.m. shorter and lom.m.
narrower than the Spy cranium No. I. In every anthropo-

Fl"".. 2. — Outlines of the aniero-postcrior cr.inial arch of ; .r, ordin.iry Irish
skull; A, Spy cranium No. 2; i. Neanderthal cranium; */, tlic fossil
cranium described by Dubois ; c, llic skull of a KoiilKi. H:isc--line thr
same as in Fij; i.

metric laboratory intelligent individuals are occ.isionally
measured who possess an antero-posterior cranial iliameter
very much less than that of the fossil cranium. In these cases,
however, the head is usually brachyccphalic, and presents
a high and full cranial arch. In the above taiile the
diameters of one of the smallest heads measured in the Dublin
University Laboratory arc given.'

Dubois calculates, from a comparison with ape crania, that
the fossil specimen had originally a capacity of at least 1000.
The average capacity of the European skull may be said to
range from 1400 to 1500 (VVelcker), and the Neanderthal
cranium has been computed to have had a capacity of 1200.
In this respect, therefore, the Ncandeillial skull takes an inter-
mediate place between that of the fossil form and of the
European. I'urther, it should be borne in niimi that a capacity
of 1000 is usually regarded (is indeed Uuliois points out) as
being the physiological mininuim for the hiiinan cranium.

From these considerations the fossil cranium described by
Dubois is unquestionaldy to be regaided as human. It is the

■ A female cranium from the Island of InishbofTin on the west coasl of
Ireland prcsdtts .in anicro. posterior dianicler of 178 111 in., and :i transverse
diamcler of i^q m.m. In both of these diaincteis, therefore, it is smaller
than ihr Java fossil cranium. It dilTcrs from the jailer, however, in possess-
ing a very lody aniero-postcrior cranial an h.

February 28, 1895]

NATURE

429

lowest human cranium which has yet been described. It pre-
sents many Neanderihaloid characters, but stands very nearly as
much below the Neanderthal skull a? the latter does below the
ordinary European skull. The similarity in form which it
presents to the microcephalic cranium, with which it has been
compared, is undoubtedly interesting, but on this account we
are not to conclude that it belon(;ed to a person of feebler in-
tellect than others of the same race. The Neanderthal skull
was supposed by certain observers at one time to have been
(hat of an idiot, but this idea was disposed of when other
crania, presumably belonging to the sauie geological period, and
possessing similar characters, were discovered. That the fo.ssil
cranium should in many respects resemble certain microcephalic
skulls, is not surprising : indeed, to some extent it was to have
been expected, seeing that a considerable number of this cla^s
of idiots present undoubted atavistic characters in so far as brain
and cranium are concerned.

Dubois, in his description of the fossil cranium, institutes a
close comparison between it and the crania of the higher apes,
and only incidentally touches upon its relationship with the
human cranium. He asserts that no good could aiise from a
comparison between it and the Neanderthal and Spy remains,
seeing that the latter are pathological. It is not within the
scope of an abstract, such as thi--, to take up the gauntlet on a
question of this kind. It will be sufficient to assert an entire
accordance with the views so ably advocated by Prof. Huxley,
viz. that the Neanderthal and Spy crania are typical of the
earliest human race with which we are acquainted.

It is not necessary to delay over the lemur. That it is
human in every respect, no one could for a single moment doubt.
Further, it is curious to note that its form and proportions are
tnore those of a modern than of a prehistoric thigh-bone. It
presents none of the characters which distinguish the Spy femora.
Its length is 455 m m., therefore the height of the individual to
whom it belonged mu-;t have been 1654 mm., or, in other words,
about the same as that of an average Frenchman.' From the
fact of the femur being found at a distance of from 12 to 15 m.
from the place wh'-re the cranium was discovered, as well
as from other considerations, it is very unlikely that the two
specimens belonged to the same individual.

The tooth is undoubtedly a very remarkable specimen. Its
great size and strong divergent fangs are characters which at
first sight appear to separae it widely from an ordinary human
upper wisdom tooth. Hut we know that in low races, such as
the Australian and the Negro, and also in the ancient rNfeander-
thaloid race, the wisdom tooth has not undergone the >ame
retrograde changes which we observe in the European and
other mesogna'hic or orthognathic people. If we take the
mean of the antero-posterior and the transverse diameters of
the crown of the fossil tooth, we get a result of 1 3 '3. A right
upper third molar extracted from the jaw of a negro, treated in
the same way, yields a result of 11 '5, whilst three Irish upper
wisdom teeth, selected at random, give an average of 9. The
negro tooth is thus seen, in p int of size, to be as far removed
from the European tooth as the fossil tooth is from it, and the
same may be said for the condition of the fangs. The fossil
tooth, so far as one can judge from the figure, is fashioned more
after the human model than the simian. The variability of an
upper wisdom tooth in man is very remarkable, not only in
regard to size, but also in the disposition of its cusps and
fangs. '^

From what has been said, it will be seen that the skull and
the tooth, even granting that they are from the same individual,
present no such characters as would warrant the formation of a
new family. The cranium at least is undoubtedly human. Most
certainly they are not derived from a transition form between
any of the existing anthropoid apes and man ; such a form
does not and cannot exist, seeing that the divarication of the ape
and man has taken place low down in the genealogical iree, and
each has followed, for good or bad, iis own path. The so-called
Pithecanthropus is in the direct human line, although it occupies
a place on this considerably lower than any human form at
present known.

* Topinard givts the .iverageli'-ight of the French as 1650 m.m.

• III the museum of the Dublin School of Denial .\iia omy there is an
upper wisd >in t .oth e<ctr.icted from rhc maxilla of an Irish nan, the crown of
wvhic I prcsenlsa lran>vcrse di.i neler of 13 m. 11., anj an antero-po-tcrior
dum Icr of 12 in.m. (mcin rcsu't t2'5i: wSich pos-cs.cs seven cusp- and
four siO'it fangs; two of ine laiter hcini; partially fused. Tftis t oth is
¥try little smaller than the wisdom tooth of the fossil form, and is more remark-
able in the way of cu>ps and fangs.

NO. 1322, VOL. 51]

UNI VERS! TV AND ED UCA TIONA L
INTELLIGENCE.

Oxi'ORD. — The Biological Club held its jubilee meeting on
Saturday last, when the professors of the biological lacul ies in
the Univ rsity were cntettained to a commemorative dinner
given in Merton College. The ravages of influenza unfortun-
ately deprived the Club of the presence of several familiar
membersand of more than one expected guest ; but the prestnce
in Oxford of Prof. Baj ley Balfour gave the Club an opportunity
of extending its welcome to an old friend and an additional
distinguished visitor. In the absence of Mr. G. C. Bourne,
the presidential chair was taken by Mr. Henry Balfour, of
Trinity. Profs. Bayley Balfour and Lankester replied for the
guests.

In accordance with a recommendation from the Board of
Faculty of Natural Science, the Council has approved of the
subject of Astronomy being added to the list of subjects which
may be offered in she Honour School of Natural Science. For
a reason which is not very obvious at first sight, a can lidate
who offers A-tronomy as a final subject must have obtained
honours in the first or second public examination, but need not
have passed any of the preliminary science examinations ; and
a candidate who has passed the science preliminaries is not
eligible to compete in the H-mour School of -Astronomy unless
he has obtained honours in ihe first or second public examina-
tion. The object of this rule, which places the Schonl of
Asironomy in a position different to that of any o her science
school, is to compel candidates to take Honours either in
.Mathematical Moderations or Finals before entering on
Astronomy. But the object is not attained, for as the s'alute
now runs, a man « ho has taken honours in Classical Muderatons
or in any Final H mour School may enter for the Astronomical
School, whilst a man scientifically trained cannot. It may be
hoped that the rule, which as it stands is absurd, may soon be
reciilied. The subject of Asironomy has long been an op ional
or additional subject in the Honour School of Natural Scence,
but like other additional sulijects, has not attracted sludenls.
Asironomy having asserted its claims to recognition. Anthro-
pology has followed its lead, and the Faculty of Natural
Science has by a large majority sent up a recommendation to
Council that the subject of Anthropology should be added to
the Finrl School. The answer of Council has not yet been
received.

In a Congregation held last week, the Curators of the Univer-
sity Chest were empowered to make sundry payments to the
Curators of the Botanic G^irden, to bring up the whole income
of the Garden during eath of the next four yeais to a sum
sufficient to defray its expenses.

Mr. G. C. Bourne. Fell)W of New College, has been elected
a Delegate of the University Musfum, in place of .Mr. E.
Chapman, Fellow of Magdalen College, resigned.

Cambridge. — The vacancy in the Sadlerian Professorship,
caused by the death of Ur. Cayley, has been filled up by the
election o( Dr. \. R. Forsyth, F.K.S., University Lecturer in
Pure M.ithematics. Dr. Forsjth is well known as ihe author
of standard text-books on Differential Equations and the Theory
of Functions, and of many p.npers on tf^e higher b'anchc-s of
pure mahemaiics. He is a Fellow of Trinity, and a member
of the Council of the Senate.

Dr. Charles Waldsiein, R-ader in Classical Archaeology,
has been elected to the .SUde Professorship of Fine Art, vacant
by the r lirement of Prof. Middlelon.

A shower of "fly-sheets" has fall'-n on ihe Universily on
the question of requiring further evidence of power to write
essavs in the various degree examinations. The q le lions will
be decided by the vole of the Senate on Thursday allernoon.

Since 1892 there has been a decrease in the numtier of
candidatrs lor entrance into the Central Techr.ical College at
.South Kensington. But though fewer candidates have pre-
sented themselves, the numlirr adnitted is about ihe same,
indicatng either that the examii ers lowrred the in micnlati m
standard, or that candidates were better prepared for ihe ex-
amination. In the refiort of the work of ihe College during
ihe session 1893-94. vaiiois cau-es are given 10 .Tccoiint for the
din.inulion ol can iida'es One is ihe great inc ea^e of lacili-
ties for obtaining technical education 1.1 London and m the
provinces since the College opened. To what extent this in-

430

NATURE

[February 28, 1895

crease of schools for technical education may help or hinder the
development of the Central Technical College remaini to be
seen. If to ^onoe extent it increases the competition for
students, on the other hand it may, in the long run, more than
compensate for this by increasing the public appreciation of the
value of technical education. It is also su^^ested that probably
the falling off in the number of candid.ites for admission is
chiefly due to the continued commercial depression, and happily
this is a disadvantageous condition which may be expected to
pass aw.iy.

A copy of the programme of the College, received at the
same tir.ie as the report, shows that the College is far and
away in advance of similar institutions in London, and is in
the highest degree competent to provide "for the higher
technical education, in which advanced in'^lniction shall be pro-
vided in those kinds of knowledge which bear upon the
different branches of productive industry, whether manufac-
tures or arts."

SCIENTIFIC SERIALS

American Journal of ScirnLC, February. — On the relation of
gravity to continental elevation, by T. C. Mendenhall. De-
terminations of the intensity of graviia'ion made by the Coast
and Geodetic Survey, and by Commander Deffo'ges, and ex-
tending across the North American con' inent, bring out the fact
that the deviations from the values of gravitation as deHuced
from the theoretical shape of the earth's spheroid, are in a direct
relation to the elevation of the observing station above sea-level.
.\n explanation based upon differences in the density of the
surface layers is difficult to find, but the fact is undoubted. —
Glacial phenomena of Nf wfoundland, Labrador, and Southern
Greenland, by G. F. Wright. The ice-sheet of Southern
Greenland formerly sent glaciers down through all the fiords,
filling ihem to a height of about 2000 feet, and pushing even to
the very margin of the continent. Greenland, iherctore, like
the re.st of the world, has had its ice age, which has already
partially passed away. During the maximum of the ice
extension, ihe mountains bordering the sea in Southern Green-
land formed innumerable "nunataks." The ice was not thick
enough to cover them in solid mass, and there is no probability
that the ice extended far out into Davis Stiaits. In Labrador
and Newfoundland, on the other hand, all the mouniains were
completely covered with gL-icial ice, which extended far out
over the borderini; coniinental plateau. The facts point to con-
siderable preglacial elevali.ins of land, followed in Labrador, at
least, by a period of extensive depression below the present
level, and subsequent gradual elevation. There is evidence of
the recent dale of the glacial period, while the indicaiions of
recenlchangesof level point 10 terrestrial rather than astronomical
causes to account for the vici.ssiiudes of the glacial leriod.
— The I'ithecanlhrofu$ ereclus, Dubois,' from Java, by O. C.
Maish (see pp. 428-29).

liultilin of the American Malhematieal Society, vol. i. 4 (New
York, January 1895) — A pathetic interest is attached to the
second article, " Note on a memoir in Smith's collected papers,"
as it must have been amongst the last pieces of work d<ine by
Prof. Cayley. The memoir is that on the Theta and Omega
Functions (Smith papers, vol. ii. pp. 415-623). The notice is a
very slight one, and gives an abstract of the contents of the
memoir —The opening paper is a presidential address, delivered
iKfore the American Mathematical Society at its annual mett-
jog, December 28, 1894, •>' which the title is, " The Past and
Future of the Society." Dr. McClintock traces the growth of
the Society from in origin in 188S as a small mathematical club,
meeting at Columbia College, whose first meeting was called by
a circular signed by three young men, up lo its present mem-
bership ol 251. A paragraph points out that the pioneer ol all
these mathematical socie'ies which have subsequently sprung
up was the Lond .n Mathematical Society. " There hid been
no previous example of a similar organisation, and fears were
felt and expres-ed that its management mi);ht natur.illy drift
into Ihe hands of a few havint; time and energy to give to its
affairs, and that there might thus be serious danger of its falling
into the control of a clique. The lapse of time has developed
Ihe fad that Ihe leading members ol that Socie'y have been
men o( broad views, unusually free from personal prejudice, and
<iuick 10 recognise talent wherever displayed. VVc may almost

NO. 3122, VOL. 51]

her P

ccnclude frcm Ihe hittory of that Society that proficiency in the
science of maiheiralics is distinct evidence of a well-bnlonced
mind." We repeat the wish we have previously expressed for
the conlirued success ol this flourishing young branch. In the
Notes the new officers ard Council are given, the new President
being Dr. George W. Hill.— A long list of new publications
closes the number.)

In the numbers of the Journal of .Si'/oty for Janu.aiy and
February, new plants are descrihed by Mr. A. Fr)er from
Scotland (a new hybrid Polamogelon); by Mr. R. P. Murray,
from Tereriffe ; by Mr. W. Fawcett, from Jamaica ; and by
Mr. H. N. Ridley, from Ihe Malay Peninsula. Mr. A. Bennett
discusses the claims of /uncus lcinii< to r.ank as a Kritish
species.

SOCIETIES AND ACADEMIES.
London
Chemical Society, February 7. — Dr. II. K. Armstrong,
President, in the chair. — The following papers were read :
The action of heat on ethylic S-amidocro|onate ; Part ii , by
J. N. Collie. During the destructive distillation of this salt,
oydimethjl a' ethoxypyridine, a dimethylpyrrol and a pyridine
derivative, C,jH,N„0, are produced together with ethylic
lutidonemonocarboxylate. — The acidimrtry of hydrogen fluo-
ride, by T. Haga and Y. Osaka. Phenolphthalein is the best
indicator to use in the titration of hydrofluoric acid. The
authors' experiments with litmus suggest that the molecular
composition of hydrogen fluoride is II3F3 or H4F4. — Composi-
tion of ancient silver ornaments from Peru, by Miss C. Walker.
— Molecular change in a silver amalgam, by Mi^s F. T. Little-
ton.— On heating silver amalgam, preferably of the composition
.•\g Hgj, considerable swelling occurs ; this can only be attri-
buted to molecular change, inasmuch as gas is not evolved.
Sulphocamphylic acid II., by W. II. Perkin, jun. Further
evidence has been obtained indicating that this acid has the
composition C8H,._,(S03ll).COOH ; the acid yields two
isomeric acids CjIlii.COOH on fusion with potash. Oiher
new derivative; have been obtained. — Derivatives ol eihylor-
Ihololuidine, by W. MacCalKim, jun.— Acetyl derivatives of
bcnzaconine and aconitire, by W. R. Dunstan and F. II. Carr.
A number ol unsuccessful attempts have been made to convert
bcnzaconine into aconilinc by intioducing an acetyl group ; two
isomeric triaceijlbenzaconiiies and a telr.icct)llicnzaconine are
obtained on acetylalion. The authors have also prepared di-
and triacetylaconiiine and triacetylpytaconitinc. — Aconitine
aurichlorides, by W. R. Dunstan and II. A. D. Jowclt. A new
examination of the three modifications of aconiiine aurichloride
confirms the authors' previous assertions as to the existence and
natuie of these compounds. The alcoholaie of aconitine
aurichloride dc-icribed by Freund and licck is the 18-autichloride
containing a little alcohol.

Entomological Society, February 6. — Prof. Raphael
Mcldola, F. R.S., President, in the chair. — Tne President
announced ihat he had nominated the Kight Hon, Lord Wal-
singham, F.R.S., Mr. Henry John Flwcs, and Prof. lidward
H. Poulton, F. R S. , Vice-Presidents of the Society for the
Session 1895-96. — Sir. W. F. II. HIandford m.ade some re-
marks regarding Mons. Brongnian's donation 10 ibe library, of
his monograph entitled " Rccherches pour servira I'hisioire des
Inscctes Fossiles des Temps Primaires." Mr. lilandford also
called attention to figures of pupa; of species of Sf-algii
(l.ycacnida;), in the Journal of the Bombay Natural Hisiory
Society. A discussion followed, in which Mr. Ilaiupson and
Mr. McLachlan look pan. — Canon Fowler exhibiiid, on behalf
of Mr. C. A. Myers, an unusually fine specimen of Splu-ria
rclietisi, growing dom Ihe prolhorax of an underground larva
ol a Hrpialiis, supfiosed lo be //. vireicens, f^om New Zealand.
Mr. McL.ichlan said that there was n doubt whether the cater-
pillar slioiild be rtfcricd lo this species. Mr. Blandfnrd staled
tbal the French Government had set aside a .sect on of Ihe
Pasteur Instituic at Paiis (or the study o( cniomi.phagnus fungi.
-Prof. L. C. Miall, F.R.S., and Mr. N. Walker, communi-
cated n paper eniitled "On the Life Histmy ol J'.moma
cane.'cens (Psychodida;)," with an Appendix by Baron Oslin-
Sackcn. — Heir Jacohy read ap.npir entitled "Contributions
to C)Ur Knowledge o( Aftiian Phyiophagous Colcopicra." Dr.
D. Sharp, FRS., remarked that Etichscn began Ihe "In-

February 28, 1895]

NATURE

43 i

sekten Deutschlands " some sixteen years ago, and as he was
engaged on a cla'isification of the Coleoptera of the world, he
included a considerable number of these exotic species in his
work. — Mr. G. F. Hampson read a paper entitled "Descrip-
tions of New Heterocera from India."

Mineralogical Society, February 5. — Dr. Hugo MiiUer,
F. R. S., in the chair. — Prof. Judd read a paper on some simple
crys'alline rocks (massive minerals) from India and Australia.
From specimens supplied by Mr. T. II. Holland, of the Geo-
logical Survey of India, Mr. P. Bosworth Smith, Lite Govern-
ment Mineralogist at Madras, and Mr. C. Harrington Brown,
the author was able to make known some new types of rocks.
Two remarkable forms of corundum-rock were noticed, one
from Pipra, S. Rewah, first brought to the knowledge of
mineralogists by Mr. F. R. Mallet, and the other from Hunsur
Talug, in the Mysore State. A fibrolite rock, derived from the
same district as the last, was also noticed. A new variety of
tourmaline (schorlj-rock with a fibrous texture, having a wide
distribution in India, was likewise described, and an analysis,
together with a descrirition of the optical properties of the
mineral, was given. From the Bingera district in New South
Wales, two dykes were described as traversing masses of serpen-
tine, one heing composed of a green garnet-rock (urossularite?)
yielding gold, and the other of picolite, the chrome-spinel.
— The Earl of Berkeley read a paper on an accurate
method of determining the densities of solids, in the
course of which it was shown that by taking suitable
precautions with a pyknometer having a thermome'er stopper
and a capillary at the side, re>u!ts accurate to 003 per cent,
could be obtained. The actual values for different crops of
rubidium alum were 1-8884, 1-8885, I 8885 and 1-8889. '1 he
chief point of the communication was that the evaporation of
the lir|uid used in the ol>serva'ions (CCI4) from the him formed
between the stopper and the neck of the pyknometer, instead of
lieing a source of error, is utilised to bring the level of the
liquid into coincidence with the mark on the capillary. — Prof.
Church made a communication on the derermina'ion of mineral
densities. Three points were specially referred to : The em-
ployment of dilute alcohol instead of water was recommended
as enabling full advantage to b; taken of the sensitiveness of
an assay balance ; the results quoted for specimens under two
grams in weight were probably correct to -003. A method of
removing interstitial air by first replacing it with carbon di-
oxide, and then absorbing this gas by an alkaline solution or
byboiled water was descritaed. An account was next given of a
method of determining relative densities by means of mercury,
the volume of mercury displace 1 by the mineral being weighed.
Although no novelty was claimed for these methods, special
precautions ill their conduct were nam<d, and illustraiions ad-
duced of their application to the determination of mineralogical
problems.

Cambridge.

Philosophical Society, February 11. —Prof. J. J. Thomson,
President, in the chair. — On a method of determining the con-
ductivities of badly conducting substances, by Prof. J. J.
Thomson. A sphere of the substance the conductivity of which
is to be determined is placed inside a coil A through which
very rapidly alternating currents are passing. The currents
induced on the sphere react on those in the coil. K small coil
H placed in series with A contains a highly exhausted bulb in
which a ring discharge is produced by the alternating currents.
.\ny change in the intensity of the currents through A produces
a change in the brightness of the discharge through the bulb
inside B. The effect produced by the sphere inside A is
measured by the change in the brightness of the discharge
within B, and as the elfect produced by the sphere depends on
its conductivity, the observaion of changes in the brightness of
the discharge makes it possible to compare the conductivities of
different substances. The paper contains applications of this
method to the study of the conductivity of electrolytes under
very rapidly alternating currents, of rarefied gases, of gases
when entermg into chemical combination, of (lames, and 01 the
effect ol the formation of drops of water from aqieous vapour. —
Note on the calinraiion of the wire of a Wheaistone bridge, by
Mr. li. 11. Griffiths.

Berlin.

Physiological Society, January 4, — Prof, du BoisReymond,
President, in the chair. — In the discussion on Prof. Waldeyer's
discourse (of December 2!, 1S94), Dr. Benda and Dr. Rawitz

NO, 1322, VOL. 51]

laid stress on the anatomical difficulties which stand in the way
of the generalisations of Golgi's school, and Prof. Gad made
his protest from the physiological point of view. Prof.
Waldeyer recognised the propriety of the objections made
against the newer views as to the minute anatomy of the
nervous system, views due to those recent methods of re-
search which have led to a very distinct advance in knowledge.
Dr. Ziegenhagen communicated the results of his researches on
the development of the blood-vessels in trout-embryos, based
on observation of the living object, on injections by Wert-
heim's method, and on photographs.

January 18. — Prof, du Bois Reymond, President, in the chair.
— Dr. Benda explained the preparations he exhibiied of
nerve-endings in muscles made by Prof. Sihler, of Cleveland.
— Dr. Rawitz described a new method of staining cells with
aniline dyes, which consists in first mordanting the tissues,
harrtened in P'lemming's fluid, with tannin and tartar emetic,
and then treating them with the dye. By this method of
" adjective "staining, only the protoplasm of the cell is coloured,
not the nucleus. The same speaker next described some results
of his method as applied to resting-cells of salamander testis.
The nucleus shows the brown-coloured chromatin filaments ;
the linin network and the distinct nuclear membrane are of
a pale red colour. In the middle of the protopKasm, at some
distance from the nucleus, is the dark-red attraction sphere
with the centrosome in its midst. Close-set meshes of the net-
work of red fibrils, which permeate the protoplasm, and are in
other pans less close-se-, join on to the periphery of the
sphere, and are in direct communication with the nuclear
membrane and the linin filaments. Occasionally the attraction
spheres of two neighbouring cells a'e joined together by a dark-
red filament. — Dr. Cohnstein described experiments on the
action of intravenous injections of sodium chloride on the com-
position of lymph and blood, and showed that the observed
variations of quantity and of the amount of water and salt in
the lymph, as also the changes in the amount of salt in, and
concentration of the blood, could be adequately explained by
the purely physical processes of diffusion and filtration.

Meteorological Society, January 8. — Prof. Hellmann,
President, in the chair.^Dr. L. A. Bauer discoursed on the
secular changes of terrestrial magnetism. From the observa-
tions available at an extended series of stations he had deter-
mined the declination and dip of a magnetised needle freely
suspended at its centre of gravity, and had compared the curves
of secular change thus obtained with the corresponding formulas.
Taking older compass-charts additionally into consideration, he
found that the curves of secular change must contain loops.
If one imagines a magnetised needle, freely suspended at its
centre of gravity, to be carried round the earth along a given
parallel, one obtains the momentary curve of terrestrial
magnetism for that parallel, and this curve corresponds to the
curve of secular variation. This curve further shows a distinct
loop, as, for example, for the parallel 40' N. In the discussion
which followed, the President drew attention to the fact that
the statements of the oUler travellers as to compass bearings
cai.not well be used for determining the components of terres-
trial magnetism, since each compass was specially arranged in
order to show the astronomical north-pole, and hence it is
necessary, first of all, to know what this special arransjement
was before their indications can be used. — Dr. Kassner de-
scribed a "fohn" wind in the Riesengebirge, which was very
marked on Novcjjber I and 2 last, on the north fall of the
mountain, and caused by the high temperature and excessive
dryness. The dryness and great transparency of the air was
observed as far as Breslau, a distance of 100 kilometres.

Physical Society, January 11. — Prof, du Bois Reymond,
President, in ihe chair. — Dr. .-Mtschul made communications
from the Raoul Piclct Institution, dealing first with the
influence of intense cold (-70° to -200" C.) on along series of
chemicil processes, and in the next place on physical processes,
such as phosphoresence, &c. He then reported upon experi-
ments on the behaviour of bodies at the critical temperature.
The disappearance and reappearance of the meniscus .v as found
to take place always at the same temperature as lung as the
warming of the substance was uniform. It was found that the
critical temperature is a better criterion of the chemical purity
of a liquid than are its melting point and boiling point, and a
number of instances were cited where minute impurities altered
the critical temperature by many degrees. Solutions of solids
when heated above the critical temperature gave no precipitate.

432

NA TURE

[February 28, 1895

the solid remaining dissolved in the gaseous vapours. Solutions
of colouring matter behaved similarly.

January 25. — Prof, du Bois Reymond, President, in the
chair. — Mr. .-Vrchtnhold discussed the principles and advantages
of two recently projected telescopes, of which one with a
44-inch object-glass and short focal length is to be set up in the
Berlin Industrial Exhibition in May 1896, while the second,
with a 50-inch object-glass, is to be taken in hand later on.
The glass for the first of the two is already cast by Dr. Schott,
of Jena, and is to be ground according to scientific principles
by Dr. Steinheil. The speaker further discussed a series of
fundamental novelties in the mounting of the telescopes, by
which the cost of the same would be materially reduced. The
discussion, which was then opened by Prof, von Bezold, on
behalf of Piofs. .-Vuwers and Vogel, and continued by Prof.
Lummer, was adjourned to the next meeting.

[Notice. — In the report of the meeting of the Physiological
Society of December 7, 1S94, Nature, vol. li. p. 2SS, for
" Dr. G. Joachim," read " Dr. G. Joachimstal."]

P.\RIS.

Academy of Sciences, February iS. — M. Marey in the
chair. — On Neumann's method and Dirichlet's problem, by M.
H. Poincarc. — On the form of the intrados of arches, by M. H.
Resal. — On the kinds of chlorophyll ; remarks a prof os of the
note by M. Ktard, by M. .Arm. Gautier. The author claims
priority for the proof that several chlorophylls exist, and that
chlorophyll contains no iron, but contains organic phosphorus. —
On the agricultural value of aluminium phosphates ; remarks
apropos of M. Andouard's note, by M. Arm. Gaulier. In 1893
the author showed that amorphous aluminium phosphate
was of value in agriculture owing to its solubility in the products
of decomposition present in soils. This does not exiend to
crystallised phosphates of aluminium or of aluminium and
calcium. — On the estimation of tannic compounds, by M. Aime
Girard. — Remarks on atomic weights, by M. Lecoq de
Boisbaudran. The author mentions a method of classification
of the elements which enables him to calculate their
atomic weights as well as predict their properties ; this
system has not yet been published. According to it, argon
belongs to a group of elements of which no other members are
yet known. They should be octads of atomic weights as follows :
200945, 3640 ±008, 8401 ±020, 13271 ±015 ; (O = 16).
They should be m.-talloids, the first two members relatively
abundant, the others rare. Taken in order, they should
respectively be more volatile than oxygen, sulphur, selenium,
and tellurium. — The scope and method of a work on
the " theory of algebraical functions and their integrals," by
M. .\ppell and M. Kdouard Goursat, is explained in a short
note by the former. — On the astronomical inscription of Kes-
kinto, by M. Paul Tannery. The author draws conclusions
with regard to the state of knowledge of planetary periods
about 150-50 B.C. — On a surface of the sixth order, allied to
abelian functions of the third type, by M. G. Humbert. — On
the properties of amorphous silicon, by M. Vigouroux. These
properties are very fully given. Speaking generally, amorphous
silicon prcjiarcd by reduction with magnesium somewhat re-
sembles crystalline silicon in properties. Though somewhat
inert at lower lemperatures,, at high temperatures it is chemi-
cally very active. — On the oxidation of ihe tannin of the cider
apple, by M. L. Lindet. This oxidation appears to be due 10
the action of a ferment of the l<ucose type. — On the composition
and an.aly5is of eaux-de-vie, by M. X. Rocques. — On the seeds
of the .Mc.ibi, by M.\I. II. I.ecomte and A. Hcbert. An account
of a tree found in French Congo, and of a fat produced from
its seed.'. — On ferrocyatiide, rutheniocyaniilc, and osmiocyanide
nf potassium, by M. A. Dufel. A crysialiographical paper giving
measurement.s of axial ratios, angles, and optical constants of
<i) K,FeCy,.3U,0,(2).K,kuCy„.3H50, (3) KjOsCyo-sHjO- A
remarkable similarity is shown by ihcse compounds throughout
the extensive .series of mcasuremcnis given. — On moditicaiions
of the blood, brought about by the thermal treatment wiih Hour-
boulc water from the spring Choussy. Pcrricrc. by M. Ph.
Lafon. Conclusions from results of many analyses (quoted) :
(I) In cases of chloro-an.xmia there is (.'cnerally a notable in-
crease of red corpuscles and oxyhxmoglcbin in the blood of
patients, due lo the treatment. (2) In cases of leucocytscmin
the treatment produces a diminution of the numbers of white
corpuscles. — On the nucleus and nuclear division in the Bent-
itnia, by M. Alphonse I^bhc. — On egg-deposition of Vesp>a

NO. 1322, VOL. 51]

crabro, L. ; conservation of heat in the nest, by M. Charles
Janet.— Observations on the upper Tongrian or Stampien strata
in the Chalosse, by M. L. Reyt. — Considerations on conlact-
metamorphism, derived from a study of the contact phenomena
of Iherzolite in the Pyrenees, by M. .\. Lacroix. — Mineraiogictl
composition and structure of the silex of the Paris gypsum, by
Ml L. Cayeux. Conclusions : (l) The siliceous nodules from
gypsum, known as silex, have an essentially different micro-
structure and mineralogical composition Irom silex properly so
called. (2) They result from a substitution of silica lor gypsum.
(3) The silicificalion of gypsum causes the production o( some
one of the arrangements of which quartz is capable. (4) The
ultimate term of the series of transformations of saccharoidal
gypsum, under the action of silica, is the production of wholly
quarlzose plates, having the same structure as quartzites.—
Earthquake recorded at Grenoble, a note by M. Kilian,
February 3, 6h. 2m. 40s. morning.

BOOKS, PAMPHLETS, and SERIALS RECEIVED.

l!ooK?. — Introduction to Physiolocical Psychology : Dr.Th. Ziehen, trans-
lated, 3nd edition (Sonnenschein). — .-Vn Elementary Text. Book of Anatomy :
IVof. H. E. Clark (BlackieV — Rep irt of Obscr\-ationi of Injurious Insects,
&C-, 1394: E. A. Ormerod (Simpkin). — Economic Classics — David Ricardo
(Macmillan). — Economic Classics — Adam Smith (.Macmillan). — A Course
of Elcmertary Practical Bacteriology ; Drs. Kanthack and Drysdale (Mac-
millan).—The Pathology of Mind : Dr. H. Maudsley (Macmiltan).— Notes
on a journey on the Upper Mekong, Siaiii ; H. \V. Smyth (Murray). —
Das System dcr Ubcrgcwalt Oder das Analytisch-Synthetischc Princip der
Natur : K. Itcyrich (Berlin, Oppenheim).

PAMPHLtiTS.— Revue de TA^ronautique, 1893, -^ Livr. : I.e Travail In-
t(5rieur du Vent : S. P. Langley (Pans. Masson). — Tableau Oeconomiquc ;
F. Quesnay (Macmillan). — Philosophical Transactions of the Royal Society
of London, Vol. 185 (iSg.j) .-V, pp 9.l-tat : Propagation of Magnetisation of
of Iron as affected by the Electnc Currents in the Iron : J. Hopkinsonand
£. Wilson (Dnlau).

Serials. — Brain, Part 69 (Macmillan). — Royal Natural History, Part 16
(Wame). — English Illustrated Mag;izine. M.arch (19S Strand).— Lotidon
Home lilonthly, March(Cox). — Journal of the Royal Microscopical Society,
February (Williams and Norgate). — Good Words, March (Isbistcr). —
Sunday Magazine, March (Isbister). — Chambers's Journal. March (Cham-
bers).—Longman's Magazine, March (Longmans). — Lc Monde Modernc,
February (Paris, (Juantin). — Century ^lagazine, March (Unwin).

CONTENTS. PAGE

What does the Chemist mean by " Valency " ? By

W. A. T 40.?

Caves and Swallow Holes. {Illustrated.) By Canon

T. G. Bonney, F.R.S 410

Our Book Shelf:—

Favvcelt : "Bulletin of the Botanical Department,

Jamaica" 412

Parnicke : "Die Maschincllen Ililfsmitlel der

Chemischen Technik." — W. T. . 412

Aikman : "Air, Water, and Disinfectants" .... 412
Clark: " .\n Elementary Te.\t-book of Anatomy " . 412
Letters to the Editor: —

Lifjiief.iction of Gases. — Prof. James Dewar,

F.R.S 413

On Ccrlain (Juestions of the Theory of Gases. —
Prof. Ludwig Boltzmann ... ... 413

Oysters and Typhoid. — Mrs. Percy FrankUnd . . 415
The Occurrence o( very Cold Days, (liilh Dia-
gram.)— A. B. M 416

IIesi>er and Phosphor. — Kumagusu Minakata . . 417
The Recent Storm in the United Slates. — Dr. Wm.

H. Hale 417

Some Suggestions on the Origin and Evolution of
Web-spinning in Spiders By R. I. Pocock . . 417

New Metric Standards 420

Notes 421

Our Astronomical Column : —

Origin of the Lunar Formations 425

7 Cassiopeix 425

■I'ht Identity of Dcnning's and Brorsrn's Cornels . . 425
The Antitoxic Serum Treatment of Diphtheria. II.
By Dr. G. Sims Woodhead ... ... 425

Dr. Dubois' So-called Missing Link. By Prof. D.J.

Cunningham, FR.S. (Il'tili Oia-rams.) 42S

University and Educational Intelligence 429

Scientific Serials 430

Societies and Academies 430

Books, Pamphlets, and Serials Received .... 432

NA TURE

43:

THURSDAY, MARCH 7, 1895.

THE ANCESTRY OF THE VERTEBRATES.
Amphioxus and the Ancestry of the Vertebrates. By
Arthur VVilley, 15. Sc, Tutor in Biology, Columbia
College ; Balfour Student of the University of Cam-
bridge. With a preface by Henry Fairfield Osborn.
(Columbia University Biological Series, II.) (New
York and London : Macmillan and Co., 1 894.)

THE observations on Amphioxus made before the
second half of the present century, amongst which
those of Johannes Mailer take a foremost place, showed
that this remarkable animal bears certain resemblances
to Vertebrates ; and since then its interest in this respect
has gradually become more apparent. The extent to
which our knowledge of its structure and development
has recently increased, is indicated by the fact that about
two-thirds of the papers dealing with Arnphioxus quoted
by Mr. Willey have appeared during the last ten years.
With the exception of the admirable account given by the
late Prof. Milnes Marshall, ast year, in his " Vertebrate
Embryology," most of the works relating to this form are
of a special nature, and to many not easily accessible. A
consecutive history of the more recent observations was,
therefore, greatly needed by those whose opportunities
did not peimit them to follow out the matter for them-
selves, and who will welcome a book written in an ex-
tremely lucid style by a naturalist who can speak with
authority on the subject.

After giving an excellent description of the habits^
anatomy, and development of Amphioxus, Mr. Willey
devotes a special section to the Ascidians. Then follows
a section on " the Protochordata in their relation to
the problem of Vertebrate descent," which includes an
account of the so-called " Hemichorda," together with a
number of details relating to larval forms, Xemertines,
and Vertebrates. On the basis of the facts stated, there

points out, mere parallelisms are often difficult to dis-
tinguish from true affinities ; and even with the increase
in our knowledge during the past few years, we are stil
so much in the dark that it is hardly possible to do more
than accept provisionally any particular theory which
appears to be supported by the greatest number of facts.
Although Amphioxus and the Ascidians have long
been recognised as of extreme importance in helping to
throw light on the question of Vertebrate ancestry, their
many peculiarities are so difficult to explain that by
many zoologists they have been attributed to degenera-
tion—more especially in the case of the Ascidians — and
on this supposition these animals can be of little use in
helping us to any sound view as to the form and structure
of the proximate ancestor of the X'ertebrates.

The more recent researches on the structure and
development of Amphioxus have, however, shown that,
specialised as this animal undoubtedly is, it can no longer
be so easily put on one side, and that it, at any rate,
almost certainly represents an extremely archaic form.
The general lines of its early development, for the know-
ledge of which we are mainly indebted to Kowalewsky
and Hatschek, are now a matter of every-day know-
ledge, and are almost universally accepted as the best
possible startmg-point for the study of Embryology gener-
ally. In the present notice we can only refer to some of
the more recent discoveries and theories as stated by
Mr. Willey. .

The curious tongue-bars in the gill-slits, which are only
known to be represented elsewhere in Balanoglossus,
are supposed by Mr Willey to be the " functionally active
organs, of which the thymus of the higher forms is a
metamorphosed derivative." This view is supported by
reference to Dohrn's account of the development of
the thymus in Selachisms. In a note on p 42, the meta-
pleural folds of Amphioxus and the evolution of the
lateral fin-folds and lateral line of Vertebrates are made
the subject of a hypothesis which cannot be done justice
to in a few lines. The discovery of the e.xcretory tubules
by Boveri and Weiss, is one of the most interesting

is a considerable amount of theoretical matter dealing

with the complex question included in the title of the | points which have recently come to light with regard to

book, in ihe discussion of which the author is not dog- Amphioxus ; and Mr. Willey supports Boveri's view that

matic, and makes the distinction between fact and theory
clear to the reader. Of the very few inaccuracies we have
noticed, mention need only be made of the statements with
regard to the cilia on the ectoderm of craniate \'erte-
brates, on p. 176, and to the distribution of the ganglion-
cells in the nerve-cord of .\nnulatcs, on p. 260, both of
which require modification. The figures, which are 135
in number, are extremely good and clear, not a few of
them being taken from the author's original papers ; and
a good bibliography is given at the end. Altogether
we congratulate Prof. Osborn on the publication of the •
second of the series which is appearing under his
editorship.

The problem of the ancestry of the Vertebrates has
been approached from many dilTerent points of view, and
some of the various theories advanced — such as the well-
known "Annelid theory '' of .Semper and Dohrn — have
been supported by so many facts and arguments as to
gain for them many adherents. Others, again, were less
fortunate, and cannot be said to have held the field at
all. In all such phylogenetic speculations, as Mr. Willey
Nj. 1323, VOL. 51

in spite of their special peculiarities, they represent the
pronephric system of \ertebrates, and that the pro-
nephric ducts of the latter are partially homologous with
the atrial chamber of Amphioxus. This conclusion
is especially important as furnishing another argument
against the Annelid theory, to which, moreover, the
nervous system of .Amphioxus lends no support, although
its peripheral portion " can only be compared definitely,
at present, in its broader features, with that of the higher
Vertebrates."

The remarkable asymmetry of the larva: of Amphioxus
has probably no ancestral significance, and Mr. Willey
concludes that it " is of no specific advantage whatever
to the larv.-v, but is merely a stage, which has been pre-
served in the ontogeny, of a topographical readjustment
of parts necessitated by the removal of the mouth from
its primitive mid-dorsal position in consequence of the
secondary forward extension of the notochord, which
has thus caused a virtual semi-rotation of the pharyngeal
region of the body. On the other hand, the forward
extension of the notochord is a distinct advantage in

U

43-1

NA TURE

[March 7, 1S95

later life, since by giving resistancy to the snout, it enables
the animal to burrow its way into the sand with such
astonishing facility, while the fact that it grows to the
front end of the body at a very early stage in the em-
bryonic development, long before it comes to be put to
this definite use, must be regarded as an instance of
precocious development, of which there are numerous and
otherwise inexplicable examples in the lield of com-
parative embryology."' The author regards it as probable
that the proximate common ancestor of Amphioxus and
the higher X'ertebrates was characterised by the pos-
session of from nine to fourteen pairs of gill-slits,
counting the "club-shaped gland" as representing the
antimere of the first primary slit.

.-Vfter an account of the structure of the .Vscidians, these
animals are compared with Amphioxus, and are defined
as " more or less Amphioxus-like creatures which have
become adapted to a sessile habit of existence.'' Their
embryology is then described, and it is pointed out that
development proceeds along parallel lines in them and
Amphioxus '' up to a certain point, and then at the time
of the outgrowth of the tail in the embryo of the former,
and the hatching of the embryo of the latter, divergences
set in." The precocious formation of the larval tail in
Ascidians is shown to be one of the chief evidences of
the abbreviation which has occurred in the development
of this group.

Metamerism — " that fetish of the morphologists," as
lirooks calls it — may, as this author points out in his
monograph on Salpa, " have been acquired by the
ancestors of the \'ertebrates after the divergence of the
Tunicates " ; and consequently, even if the supposed
metamerism of the tail in Appendicularia had not now
been definitely shown by Seeliger and Lefevre to be arti-
ficial, it could hardly have been considered of r.nccstral
significance. Mr. Willey recognises the secondary .-.ature
of the "so-called metamerism'' of the tail in this animal,
and is inclined to conclude that " the Appendicularix-
represent Ascidian larvx- which have become secondarily
adapted to a pelagic life, and have acquired the faculty
of attaining sexual maturity." We feel, however, that
the arguments brought forward are hardly sufficient to
balance those in favour of the view held by Brooks and
many others, that Appendicularia is the more primitive
type, though until the development of this form is known
we cannot, as .Mr. Willey points out, decide definitely
between these two views.

,\s already indicated, T.ateson's grouping of ilalano-
glossus, Cephalodiscus, and Rhabdopleura into the divi-
sion Htmichordit of the group Protochordata, is accepted
by the author, and these forms arc described and com-
pared, and an account of the development of Tornaria
and of Kchinoderm larv.L' given. Although we fully
appreciate the general force of the quotation from Weis-
mann, given at the head of .Section \'., the perusal of the
foUowmg pages will not, wc fear, be convincing to every-
one that it applies in this particular instance. Such
arguments as those brought forward by .Spengel in his
great monograph on the Enteropneusia cannot easily be
put on one side, and we must make allowance for the
principle of parallelism in evolution.quite as much in this
case as in that of the Annelid theory. Nevertheless,
whether the llcmichord.i hypothesis proves to be true or
NO. 1323, VOL. 51]

falls to the ground, it will have h.xd its value in stimulating
inquiry.

So many other points of theoretical interest naturally
appear in considering the problem of X'ertebrate ancestry,
that one is tempted to discuss each as it arises. We must,
however, content ourselves with a bare statement of
certain only of these, and the conclusions at which Mr.
Willey has arrived with regard to them.

It is concluded "that the ventral mouth of the craniate
Vertebrates is the homologue of the dorsal mouth as we
find it in the Protochordates, .ind that its direction of
evolution has been, as was so ably maintained by Balfour,
from the cyclostomatous to the gnathostomatous con-
dition." The hypophysis is supposed to have arisen " in
connection with a functional neuropore ; when the nfeuro-
pore ceased to be functional, there was no longer any
bond of union between its inner portion, which opened
into the cerebral cavity, and its outer portion, which
opened into the buccal cavity ; and these two portions
became separated by differential growth of the cerebral
and body. walls." Much stress — we are inclined to think
too much — is laid on the pre-oral lobe, which is supposed
to be " represented in the craniate Vertebrates by the
prinnandibiilar head-cavities.'''

In conclusion, we cannot do better than quote the last
paragraph of Mr. Willey's useful and suggestive book,
which is dedicated to Prof. Lankester : —

" For the present we may conclude that the proximate
ancestor of the Vertebrates was a free-swimming animal
intermediate in organisation between an Ascidian tad-
pole and .Amphioxus, possessing the dorsal mouth, hypo-
physis, and restricted notochord of the former ; and the
myotomes, cttlomic epithelium, and straight alimentary
canal of the latter. The ultimate or primordial ancestor
of the \erlcbrates would, on the contrary, be a worm-
like animal whose organisation was approximately on
a level with that of the bilateral ancestors of the
Echinoderms." W. N. P.

A CYCLOPyEDIA OF NAMES.

The Cyclopcedia of Names. Edited by Benjamin E.

Smith, A.M. Pp. 10S5. (London : Fisher Unwin,

1894.)
'"P'HE production of a pronouncing and etymological
-1- dictionary of proper names, encyclopxdic in its
scope and fulness, must have involved an immense
amount of care and industry. The ponderous tome
which represents the result of such labour comprises

to quote from the Editor's introductory remarks —
" not only names in biography and geography, but also
names of races and tribes, mythological and legendary
persons and places, characters and objects in fiction,
stars and constellations, notable buildings and archaeo-
logical monuments, works of art, institutions (academies,
universities, societies, legislative bodies, orders, clubs,
lie), historical events (wars, battles, treaties, conventions,
&c.), sects, parties, noted streets and squares, books,
plays, operas, celebrated gems, vessels (warships,
yachts, &c.), and horses. Pseudonyms, also, which
have literary import.Tnce, are included. The only con-
dition of insertion has been that the name should be
one about which inform.ition would be likely to be
sought."

March 7, 1895]

NA TURE

435

The condition expressed in the last sentence is one
that miy be regarded as essential, and only by adopting
it as a guiding principle can any dictionary or cyclopaedia
worthy of the name be constructed. It follows from this
that the various groups of subjects could not be pre-
sented with equal fulness ; accordingly we find that
persons and places are given a much greater amount of
space than any other clas5. The personal names in-
cluded in the volume embrace not only actual biography,
but also mythology, legend, and fiction. We are chiefly
concerned with the names of men of science, and,
so far as can be judged from test references, few
names of importance have been omitted. But even
if a few omissions have been committed, it would be
ungracious to condemn the work on that score ; rather let
us marvel at the number of names that have not been over-
looked, and at the care which must have been expended in
bringing so much accurate information together. Who
but those that have had to investigate biographical de-
tails can understand the difficulties which crop up in the
matter of dates, due to different styles of reckoning, and
the differences between various authorities ? It cannot
be laid down that in every case the most trustworthy
authority has been selected ; nevertheless, there is ample
evidence in the volume to show that judicious discrimina-
tion has been used.

The geographical names given include every town,
place, or locality likely to be looked for by the average
man ; physical and political divisions of the earth ;
rivers, lakes, seas, &c. ; and natural curiosities. In the
spelling of place-names, the established usage in the
language from which the name is taken has generally
been accepted. In many cases, however, where the
established English usage differs more or less from the
native form, no general considerations can be applied.
Instances of this are : Munich for the German Munchen,
Flushing for the Dutch Vlissingen, Hanover for the
German Hannover. Having regard to the fact that there
is a tendency to return to the native form of spelling
place-names, where the difference between this form and
the Anglicised orthography is slight (as in Hannover),
the former has usually been taken. This seems to
be a common-sense rule to follow, and it enforces the
opinion of many geographers that the correct spelling of
a place-name is the local one.

The general plan of the dictionary will be understood
from the foregoing brief description. It only remains to
be said that, as a collection of proper names, the work is
the most complete one-volurne cyclopaedia that has ever
come under our notice. No scientific society should be
without the volume, and every reference library ought to
have a copy on its shelves.

OUR BOOK SHELF.

Varied Occupations in IVeainng. By Louisa Walker.
Pp. 224. (London : Macmillan and Co., 1895.)

There is a scientific and an artistic side to the kinder-
garten system of education. Froebel's graduated sets
of simple apparatus, known as " gilts," are most
valuable in training a child to observe and think. The
first of the gifts, consisting of six wool balls, coloured re-
spectively violet, blue, green, yellow, orange, and red,

NO. 1323, VOL. 51]

serve to teach elementary colours ; the second, con-
sisting of a wooden cube, a sphere, and a cylinder, is
used to familiarise children with geometrical forms, and
with the figures presented when the objects are rotated
around different axes. A number of other gifts follow
these, each calculated to develop the minds of the
infants for whom they are intended. So much cannot
be said, however, for all the " varied occupations " which
are carried on in many elementary schools. The edu-
cational value of an occupation such as that described
in the book before us, lies not in the development of
the mind, but in the training of the hand and eye. If
the elements of kindergarten knowledge have been pre-
viously acquired by the young students, there is no
harm in teaching how to weave paper mats, and to do
macramc work, though our opinion is that the child
might be better employed in object-lessons, which
naturally follow a scientifically arranged kindergarten
course. For this playing at making things is often
carried too far, and leads to technical instruction being
given before instruction in the broad principles incul-
cated by means of Froebel's early gifts. Possibly we
do not fully appreciate the value of hand and eye train-
ing for children. The greatest benefit to be derived
from such training seems to be the cultivation of the
imitative and inventive faculties. Addition and multi-
plication can be taught by the weaving occupations
described by Mrs. Walker, but they can be taught just
as well by means of Froebel's gilts. However, the
book is the outcome of twenty years' experience in
kindergarten methods of teaching, and therefore should
be of great service to teachers of children, even though its
value, when viewed from a scientific pomt of view, is
but little.

Horse Breeding for Farmers. By Alfred E. Pease.

(London: Macmillan and Co., 1S94.)
The aim and object of this little work is to impress upon
the impecunious present-day farmer the pecuniary profit
which is to be derived from horse-breeding ; and if the
balance-sheets which Mr. Pease produces are to be relied
upon, it undoubtedly constitutes a profitable pursuit.
Unfortunately, however, so much depends upon the
judgment, care, and skill bestowed by the individual in
the purchase of suitable mares, the selection of proper
sires, as well as upon the business capacity of the breeder,
when the time arrives for placing the produce upon
the market, that a profit on paper may readily be con-
verted into a loss in practice. More particularly is this so
in the case of the lighter breeds, such as the hunter
and high-class carriage horse, whose value is largely
dependent upon the thoroughness with which they have
been trained and schooled. -Mainly for these reasons we
believe that the average farmer will be best advised to
confine his horse-breeding operations to the heavier or
agricultural breeds. They possess the additional ad-
vantage of being more docile, less trouble to break in,
more useful to the farmer whilst young, and, finally, are
more readily disposed of. The other breeds are best
left to the landowners and so-called gentleman-farmer.
Holding these views, we regret Mr. Pease should devote
twenty pages to tracing the origin and history of the
English thoroughbred, the Arab, the Barb, and other
Oriental breeds.

For the rest, the book is replete with valuable in-
formation on the subject it professes to deal with, and
may be cordially and unreservedly recommended to
those who are inclined to try their luck in horse-breeding.
To our minds, the final chapter, which treats of the
ailments which horseflesh is heir to, is the least satis-
factory. This IS hardly to be wondered at, when we
bear in mind how wide a subject is veterinary science,
and how small a space Mr. Pease has devoted to its
consideration. W. F. G.

436

NA TURE

[March 7, 1895

Pnp.iratory Physics. By William J. Hopkins. (London :

Longmdns, Green, and Co., 1894.)
The course here presented is the outgrowth of needs of
the clas^ei beginning the study of physics in the Urexel
Institute, Philadelphia. It is arranged strictly for
laboratory work, and although the ground covered is not
very e.xtensive, yet sufficient has been selected for a first
couise, and that expounded to a very full extent.
.Mechanics has been chietly taken in hand, and the
numerous problems have been so arranged that the
student is able to investigate them experimentally for him-
self. A glance at the instructions and explanations shows
one that the auihor wishes at every step to instil into the
beginner the idea that habits of accurate and thorough ob-
servation must be developed, and, further, that students
must be careful, comijlete, and orderly in recording and
arranging his results. With this intention most of the ex-
periments are accompanied with printed forms illustrating
concise methods of recording the observations. The
apparatus alluded to in the text is of a simple nature, and
quite sufficient for those beginning the subject. As an
introduction, a few pages are devoted to such fundamental
points as units, errors and sources of error, coordinates,
plotting of curves, i:c. Altogether, the book will be
found a serviceable and able help to all wishing to
take part in the more simple laboratory work.

The Story of the Stars. By George F. Chambers,
F.R.A.S. Pp. 192. (London: George Newnes, Limited,
1S95.)
One or both of two qualifications are essential in a book
designed for general readers; the text mu^t be attiac-
tively written, or the illustrations must plea e the eye.
This book has neither of these claims to public favour:
the text IS stodgy and the illustrations are the very worst
that we have seen disfiguring a volume on astronomy.
The former detect is due to the author's attempt to say
something about the whole of sidereal astronomy in le:.s
than two hundred small pages; the wretched illustrations
cannot be due to his inability to find others, so this fault
must lie at the publisher's door. And yet we cannot
understand why the publisher of the Strand .Max^aziiie
and other pictorial papers could not give the same care
to the Illustration of a book on astronomy as he does to
the description of the home of some celebrity. Only in
regard 10 quantity of information are we aule to say a
favour.ible word for this book. Mr. Chambers is
thoroughly competent to collect the facts belong. ng to
the old astronomy, and to condense them. He may be
able to coinpre-.sa mass of knowledge into a s.nall com-
pass, but his latest production shows that he his not ihe !
\.OVic\\ simplex muiiditiis of a writer for the popular mind. I

Aerial i^'avi^ation : Proceeditij^s of the Internalional
Conference held at Chicaj(o, Aiif;usl 1893. Pp. 429.
(New Yo'k: American Enj^ineer Office. London:
Sampson Low, Marston, & Co., 1894.)
An International Conference on aerial navigation formed
one o( the series of Congresses which were held in
Chicago during tne summer o( 1893. The meeiings proved
to be suctessfiil, and the volume in which the pro-
ceedings are recorded shows that facts and positive
knowledge, rather than speculations or descriptions ol
things "in the air," were the order of the day. Some
thirty-five papers were presented, each containing an
account o( observations and results of experiments
carried out by scientific men or experienced engineers.
These p.ipers and the discus%ions upon them aie now
publl^he(l in a volume uniform with Mr. Chanute's
treatise on "Fl)ing NLichmes," previously noticed in
Naii;re(voI I. p. 569, l«94). Both show that many
of the proiilcrns of aeronautics and avi.ition are being
treated scien'ifically. The present volume is of special
interest to meteorologists, for it contains several papers
on the exploration ot the upper atmosphere.

NO. 1323. VOL. 51]

LETTERS TO THE EDITOR.

[The EJitor does not hold himself responsible for opinions ex-
pressed ty his correspondents. Ntither can he undertaki-
to return, or to lorrespon t with the writers of rejected
manuscripts intended for this or any other part of NATURE.
No notice is taken of anonymous communications. ]

The Liquefaction of Gases.

I DECLINE to fol ow Prof. I)ew;ir into the fre^ih crop of
irrelevant side issues r.iiscd by liis leiier in Nature of
Fe'iruary 28. Ihe charge bi ought .iijainst Pro(. Dewar,
which I think I have amply substantiated, is that he has allowed
the lmpre^slon to go abr ad that he has carried out much
original re-eirch in'o the methods of liquefyini; the more per-
manent gases, and the proper ies of the liquids produced ;
whereas his experiments have been mainly rtpetitions of work
dune I'y others.

Pr if. Dewar has not met this accusation. He has not proved
that bis methods for liipieiying the more permanent ga>es are
original methods, he has not even shown ihat lor scieniific pur-
po-es they are g lod meihods ; he lias not proved that his ex-
periments on ihe liquefied gases are either original or valuable ;
he has no aiicmpiedio r<but the actual lacis, or to deal with the
actual dates, brought forward liy Prof. Olszewski and myself.

In his last letter Prof. Dewar g vcs a list ol work "com-
menced and so far devtlo|jcl in the laboratory of ihe Royal
Insiitu ion " The list might, however, have been made a little
less grotesque by the ou.ission ol such tliin s as 'argon in
liquid air," and the " liquefaction of hydrogen," and the substi-
tution in place of these 01 a doul le &c.

When Prof. Dewar quits the region of romance, and tries to
meet the dctiniie s atcments I have made, and the evidence
alT'rded by the dates I have quuied, I .shall be rtady 10 deal
with his aigumcrrs to the best of my ability.

Cambridge, i\Iar';h 2. M. M. Pattiso.n Muik.

Eleven-year Sun-spot Weather Period and its
Multiples.

Many years ago, investigations in regard to the existence of a
period of about eleven yeara in the weather corresponding with
the eleven-year sun-spot period were actively carried out in
vari >us pans of the worlii. Much data was accumuhiieil in sup-
port ol such a period, a large pan of which was pulilished in
the earlier volumes of Naturk. Hut the iiivesiigaiions, as a
whole, showed thai the pcnod was less marked or more com-
plex than at first aniKipaied, so ihat recently less interest has
tjeen maniiesied in the subject, and indeed many express their
doubis as 10 the rxisience of such a period.

One of the complixiues which has helped lo obscure the
clevei.-year period is ihe existence of what may perhaps be
called weather harmonics, on account of the resemblance lo har-
monics in sound — thai IS, the existence of other perioos related
to the length of the first as 2, 3, 4, Jic. Thus ihe existence of
ihe eleven-year period is obscured by the existence of other
periods of 22, a, 44, &c., years.

If the leailer will turn lo the letter " On Some Tempeiatuve
Variations in France and Giecnlanil," in NatURF. ol October
II, 1894, he will find ploiied the smoothed number of frost
<f.iys ana mean July tcnipeiaiures at Pans for a laige part of
the i>ies' nl century. These curves show three marked waves
in the temperature with the crests about 1S25, 1848, and 1869,
that is, almost exactly 22 years apart. If the dales ol the chief
maxima and minima of ifie individual curves are arranged under
ditcs 22 years a(iart, as shown below, it will be seen that the
dates closely apiiroximate, thus : —
Mean dales of

maxima

.. 182s

. 1847 ..

. 1869 ..

. 1891

Frost days, Paris —

minima

. 1824

. 1848 ,,

. 1868 ..

. 1883

July temp. Paris —

iiiaxitna

. 1826-

34 ■

. 1848 ..

. 1870 ..

. 18S5

Mean d.\ics of

minima

. ISIS

• 1837 ■

1859 ..

1881

Frost day, Paris —

maxima

. 1814

. i8j9

1856 ..

1878-Sy

July 'Clip. Paris —

minima

. 181S

.842 ..

1862 ..

1881-90

If only the iwo highest maxima arc consirlered, ilicy occurred
about 1826 and 1870, or 44 years apart ; but if all the secondary

March 7, 1895]

NATURE

437

and chief maxima are considered, there are indications of an

i\ I -year period, ihus : —

Mean da'es of minima —
1814... 1825 ... 1836 .. 1847 ... 1858 .. 1869 ... 1880 ... 1891

Frost days, Paris — maxima —
1814... 1830 ... 1839 ... — ...1856... — ... 1878 ... 1889

July temp. Pari>, minima —
1815 ... 1830 ... 1S42 ... — ...1862... — ... 1881 ... 1890

In the Annals of the Astronomical Observatory of Harvard
•College, vol. xxxi. part i, p. 103, is given the average tempera-
ture tor each five years, observed at a large number of stations
in New England. The three stations having the longest records,
namely, Nov Hiven, Connecticut, Cambiidge, Massachusetts,
and New liedford, Massachusetts, are given below : —

Year.

1781-
35.

1786-
90-

<rambridge

New Bed-
ford ...

."New Haven 49*0 1 498 1 49*8

I79I-

1796-

1801-

1806-

1811-

1816-

1821- 1826-

95-

00.

05.

10,

I5-

20.

2$. 30.

1

SO '4

48 0

49 4

47'4

48-1

49-5 49 6

49-8

So'o

512

49'3

478

469

49-2 498

I83I-

35-

48-2
481

Year. j'SsS-
' 40-

1841-
45

46-6

47-8
49 4

1846- 1851-
50. 55-

47-7 47-4

48 8 486
491 48-6

1856-
60.

471

47 9
18-9

(
1861.1866-
6j. 70.

1

481 47'

49 9 ' 48-3
606

1871-
75

464
47'i

187'i-
80.

.8-5

491
517

1881-
85.

48-5

48-1
48-4

1886
90.

Cambridge

■New Bed-
ford ... 1 47'0

"New Haven 47*5

490

479
486

These records show that maxima r^ccurred in New England
about 1803, 1828, 1848, 1863, 1876, and 1S89, and minima
about 1818, 1838, 1858, and 1873. If these are arranged
according to intervals uf 22 years, as before, the following
results are obtained : —

<S9i

It will be seen that the dates of maximum and minimum
temperature correspond almost exactly with those observed in
Paris, showing how general were the forces acting to produce
them.

That there exists all over the world a tendency to a period of

Mean dales of

maxima

1803 .

. 1825 .

■ '847 ■

. 1869

Observed max. temp

New England ...

1S03 .

1828 .

. 1848 .

• 1863

Minima

1814 .

■ 1836 .

. 185S .

. 1880

Observed

1818 .

. 1838 .

. 1S58 .

■ 1873

about 33 years, is so well worked out by Briickner. that it is only
neces-ary to refer ihe reader to his treatise on " Klimaschwan-
kungen >eit 1700," to find exhaustive data on ihi> subject.

This harmonic tendency of multiplication in weather periods
has been extensively worked oui by the writer in shorter periods,
and the evidence ol its existence appears conclusive, based in
that case ona very large mass of data. It is desired to call
attention to it here, that those making future inqu ries concern-
ing sun-spot periodicity and the weather may bean he possibility
o( this phenomenon in mind. H. Helm Ci.ayto.n'.

Blue Hill Meteorological Observatory, Readville, Mass.

Abnormal Atlantic Waves.

In 1887 (Natuke, vol. xxxvii. p. 151) you kindly pub-
lished a few remarks from me on the possible volcanic
origin of the two waves which swept the d cl(s of the
steamers Umhiia and Faraday^ and which, from the da'a then
available, seemed to have ori^^inaled at a point in the Atlantic
known as the '* Faraday Reef, "and marked with a cross (-f )on
the accompanying chart. I am now able to send you the details
of a few similar cases which I have collected since then. The
exact positions of the vessels, and thediiections from which these
solitary waves seemel to come, being also marked on the chart.
In the case of H.M.S. Orontes the shiii's cours-- was not stated,
and on account of darkness and other causes the directions from
which some of the I. ther waves came are not to be depended
upon. None of these encoun'ers would have been reported had
thev not caused much damage — masts and funnels going by the
board, and bul a ks, deckhouses, and lifeboats being smashed ;
but many seafaring men can recall solitary and abnormally high
waves having siruck their vessels, although the sea was otherwise
quiet. Amongst the sirange results which thi se Mows have pro-
duced, may l-e menliunt-d that the magnetism of the steamship
Rucvi^ia was thus suddenly altered sufficiently to introduce an
error of 18' into the compass readings. The full details about
this and a few other vessels have not been obtained.

North Atlantic.

\

^^CT

X

initial.

F

\V
G
U

L
M
D

Ship's name.

'Faraday

M'lsternland

Germanic

Umbria

H.M.S. Oronles..
I'estina Lenle ...

Manhattan

Diamond

Local lime.

6 45 a.m.
2.45 a.m.

9 40 a.m.
4.40 a.m.

5 P-ni-
noon.
2 a.m.

10 p.m.

Dale.

14/2/S4
27 11,86

SS87
26/787
1 8/2/9 1
16/11/94
1 7 '1 1/94

21/11/91

L.ilitude.
North.

46 II

47 59

50 36
3" 50
36 12

50 12

51 26

53 9

Longitiiile.
We-l.

27 S3

43 57
22 8

27 8

32 50

35 23

27 31

9 52

Speed.

Knots.
6

7
4

16

9

Ship's course.) > W.-ivc's course.

N. 72° E.
S. 60° W.
N. 68= W.

Poit beam.
Bow.
Bow.

.. , ,,, 3 points on

.S. nearly u. .-" r , .

' starboard bow.

? S.E. by S.

? S. 86° W.

Lying to W.N.W.

Bow.

■>

N.W.

W.N.W,

NO. 1323, VOL. 5 1]

438

NA TURE

[March 7. 1895

The following are short summaries of each case :

S.s. FaraJay. — The wave was visible like a line of high
land on the horizon about five minutes before ii struck the
vessel.

S.s. IfisftrnJtind. — A huge wave rose to a great height just
in advance of the ship. No other similar waves were raft with.
About noon the wind had changed from S. W. to W.N.W.

S.s. Gtrmanic. — Wind \V. X. \V. with terrific squalls. Shipped
a tremendous sea over bow.

^■.r. Umlria. — The disturbance came from ^N.W. and con-
sisted of iwo waves. The first one was broken, the second one
green. The wind had previously changed from S.W. to N.W.

H.M.S. Oronlcs. — While steaming in smooth water a huge
wave broke over the vessel forward.

6. Festina Ltnte. — A sleep sea fell on board from both sides.

S.s. .\tanhattan. The sea was high, but fairly true until a
mountainous wave broke on board from N.W.

S.s. Diamond. — L)ing to, awaiting daylight to enter port.
The wave was heard some lime before it was seen, and then
seemed lo be about 40 feet high. The vessel never rose to it,
but was literally submerged for a time.

An examination of the chart will show that with the excep-
tion of the U'lilernland each wave may have originated at a
common centre, and might therefore be due to subaqueous vol-
canic aciivily. However, as the solitary waves which strike
the west coast of South America and the so-calUd Death Waves
on the west coast of Ireland are said to be regarded as pre-
cursors of storms, it is possible that these solitary Atlantic waves
may be due to a similar cause ; but even llien it is inexplicable
how a number of comparatively small and regular waves can
be convened into one abnormal one, or how the reported
changes of wind and consequent confused sea could
produce such a wave. It will be noticed that the
dates for the Festina Lentt, Manhattan, and Diavioiid arc
very close together, and therefore there is a possibility that they
were struck by (he same wave. C. E. Stromeyer.

Glasgow, February 18.

The Presence of a Stridulating Organ in a Spider.

Whilst spending a short time at Alice Springs, in Central
Australia, during the course of last year, in connection with the
Horn Scieniific Expedition, I found that it was firmly believed
by a considerable number of people, while men and natives
alike, that a spider existed in Cenlral Australia which made a
booming noise at night. Thanks to the assistance of the blacks,
the spider itself was easily captured, but I could detect no organ
capable of producing a booming sound. The animal forms a
tubular burrow, about three-quarters of, or an inch, in diameter,
which passes down for some eighteen to twenlyfour inches in
a slightly slanting direction unlil it terminates in a small
chamber capable of holding the animal comfortably. In this
chamber arc found fragments of beetles upon which the animal
has preyed, and a certain amount i>f web material ; but there is
no regular lining to the tube or chamber. The spider, which
may reach a length of two and a half inches, and a span across
the legs of five inches, proves to be J'/irictis crassipcs, belong-
ing lo the tribe Tcrrilelariir, to which also belongs the well-
known Afygale.

After li-iiening carefully for the noise, and spending with a
friend a night out in the open, in a spot where the booming could
be heard, we came to the conclusion th.at the noise attributed lo
the spider was, in reality, made by a quail.

However, we kept some dozen specimens under observation
in tin and wooden boxes, and after a few days in captivity,
during which time they were very slugi;ish, one or two of them
began to be more .active, and on irritating one of the livelier
ones (a Urge female) with a straw, I was pleased to see her
rise on her hinder legs, and lo hear her make a low whistling
noise, moving alternately the paljjs up and down on the chcli-
cetx as she did so. Whilst doing this she would make short
angry darts al the straw.

On examination it was seen that the surface of the basal
joint of the palp was provided with a somewhat ovalshapcd
comb-like structure co'npoied of hard chitinous rods of various
lengths, each enlinj in a club-shaped head. The comb is so
placed that when the palp is moved up and down it rubs against
a special part of the chelicera, which is provided with several
rows of strong, sharply-tapering spines, and Ihe sound produced

NO. 1323. VOL. 51]

can be heard, when the spider is in a box in a quiet room, at a
distance of, at any rate, six or eight feet.

I was not at the time aware of the fact that, in the Tiansa.ti^'N!
of the Entomological Society for 1S77, Mr. Wood Mason had
described a very similar stridulaling organ in another ground-
spider, M)\^,i!e stridulans, and it is interesting to note the close
resemblance between, as well as the presence of, the oi^ans in
these two genera, both of which belong 10 the tribe Terrilelaria.
The figure given by Mr. Wood Mason admirably illustr.ites the
position of the spider when it stridulates.

I hope to publish a full description of the organ in the volume
dealing with the work of the Horn Expedition.

Balpwin Spencer.

Biological Laboratory, Melbourne University,
January 24.

The Spectrum Top.

PerhaI'3 some of your readers may be glad to learn that the
curious phenomena of the spectrum top can be shown on a
screen lo a large audience. It is only necessary to paint the
usual black lines and sector on a suitable disc of glass, and
then lo mount it in a revolving stage which can be rotated in a
lantern by means of a multiplying wheel. The projected disc
of light must not be too large ; if the lime-light be used the disc
may be about 2 feel in diameter, and about double that
size with the electric arc. A great variety of elTects can be
obtained by interposing coloured glasses in the path of the
beam ; e.g. with a green glass, and in diffused gas-light, the
dark sector and lines appear to be niauve-coloured when
suddenly stopped after rapid rotation, or when very slowly
rotated, but become of a dark blue when the gas is turned off.
On rotating the disc in the usual way the lines appear to be
blue, green, and violet.

With a blue glass in gaslight the dark sector and lines
appear to be yellow when suddenly stopped, but a fine purple
without diffused light. The colours given by tlie lines at a
moderate rate of rotation are red, grey, green, and blue. With
a monochromatic red glass, the lines appear lo be blue, grey,
red, and dark red.

Is it not somewhat extraordinary that a rich blue colour can
be obtained when dealing only with monochromatic red light ?
With whatever coloured light the disc is fed, the characteristic
red lines at the centre, and blue .at the periphery, or .- /<v lersa,
seem almost invariably to appear. AUogelher the phenomenon is
worthy of further 'study by physiologists and physicists ; the
lantern appears to throw, in a double sense, new light upon this
interesting problem. The idea of employing transmitted
instead of reflected light for producing the phenomena of the
spectrum top is partly the suggestion of Mr. T. J. Walls,
instrument maker, Edinburgh, who constructed the disc for
me. Dawso.n Turner.

Edinburgh, March 4.

THE AGE OF THE EARTH.

PROF. PERRY and I had not to wait long after the
publication of his article " On the Age of the ICarth "
(Natukk, January 3, 1895, pp. 224-227) to learn that
there was no ground for the assumption of greater con-
ductivity of rock at higher temperatures, on which
his effort to find that the consolidation of the earth took
place far earlier than 400 million years ago, is chiefly
founded. In a letter of date January 13, most coiirie-
ously written to me by Dr. Robert Weber in conseipience
of his having seen by my letter to I'rof. I'erry of
December 13, that we were anxious to find how far his
experimental results regarding dillerenccs of thermal
conductivity and specific heat at dillerent temperatures
could be accepted as trustworthy, he tells me that he had
made farther experiments on an improved plan, and that
on the whole his investigations do not seem to prove
augmentation of conductivity with temperature : and he
kindly gives me, with permission to communicate lo
NAitKijthe following results, hitherto unpublishetl, of
experiments which he made in t e years 18S5 and 1S86

March 7, 1S95]

NATURE

439

on the thermal conductivities \k) and specific heats (c) of
five rocks.

Density
Basalt 30144 ... ^-O'i763 + ooo0296/ [be-

tween 0° and 60 ]
r = oT946-i-0'ooo575(/ -
60) [between 60' and
no ]
/■ = 0'oo3i7;i +000001/;
Marble ... 27036 ... £- = o'20279 + o'oci0466./

/■ = o 00540 1 1 - o ■000005. ')
Rock salt ... 2-i6r ... c = o'2i46-rOOooi7/

k = oo\n\\ - -0044/1
Anhydrite of Jura ... a'Sga ... c = o'i8o2 + o'ooo3./

/t — 0'OI23|l -O"0O24./i

iTuartz ... 2-638 ... £- = o-i754 + oooo4./

i=o-oi576|i -0-0019./;

These results show practically no change of thermal
conductivity with temperature for Basalt and Marble.
For Rock .Salt, .Anhydrite of Jura, and Ouartz, they show
diminutions of thermal conductivity amounting per 100'
C. to 44 per cent., 24 per cent., and 19 per cent, respec-
tively. They contrast curiously with the 75 per cent.
augmentalion of thermal conductivity per 100 C.
(Naturk, January 3, p. 226), used by Prof. Perry in
his estimate of the age of the earth, and they form
a practical comment on his statement (N.\ture, January
3, p. 226) :— "From the analogies with electric conduc-
" tion, one would say, without any experimenting, that as
"a metal diminishes in conductivity with increase of
"temperature, so a salt, a mixture of salts, a rock, may
"be expected to increase in conducti\ ity with increase of
" temperature."

Since the beginning of January I have myself been
endeavouring to find by experiment the proportionate
differences of thermal conductivity of rocks at different
temperatures : and before the end of January I had
made some preliminary experiments on slate and sand-
stone, from which 1 was able to tell Prof. Perry that the
thermal conductivity of each of these two rocks is
probably less at higher temperatures than at lower.
.Since that time I ha\e been arranging for experiments
on granite, in which as rapid progress as I would ha\e
liked has been impossible for many reasons, including
the necessity of standardising a Kew certificated thermo-
meter of 1886, now for the first time being compared
with an air thermometer in my laboratory. Unless its
differences from the air thermometer are much larger
than can be expected from what we know of the behaviour
of mercury-in-glass thermometers generally, it is already
almost proved that the thermal conductivity of granite
is less between 150'' C. and 250' than between 50' and
150^

.^.s to specific heats there can be little doubt but that
they increase with temperature up to the melting point
of rock, but the rate of augmentation assumed by Prof.
Perry is about five times as much as that determined
up to I2CO by the experiments of Rue ker and Roberts-
Austen {Phil. Mag., 1S91, second half-year, p. 3531 for
Basalt, and of Carl ISarus (/'/;/'/. Mag., 1S93, first half-
year, pp. 301-303) for Diabase ; these being apparently
the orily experiments hitherto made on specific heats of
rock at temperatures beyond the range of the mercury-
in-glass thermometer.

Taking the primitive temperature as 4000' C. and the
thermal conductivity and the specific heat at this tem-
perature respectively 30 times and 14). times their values
at the surface, and throwing in a factor 3 for three-fold
density at the greater depths (though the average density
of the ivhole earth is scarcely double that of the upper
rust) Perry takes the product of three factors
30Xi4lX3and so finds in round numbers 1300 times
my estimate as his corrected estimate of the age of the
earth ! ! (Nature, January 3, p. 227.)

But even if the ratios of thermal conductivities and of

specific heats at the higher and lower temperatures were
as assumed. Prof. Perry's product of the two corres-
ponding factors vastly over-estimates the age. Of this
I thought I had given a sufficient warning when I wrote
to him (December 13;, "But your solution on the sup-
position of an upper stratum of constant thickness,
having smaller conductivity and smaller thermal capacity
than the strata below it, is very far from being applic-
able to the true case in which the qualities depend on the
temperature." (Nature, January 3, p. 227.) It is
obvious that the supposed higher thermal conductivity
and the higher specific heat, if beginning suddenly at a
short distance below the surface, and continuing con-
stant to the great depth, would greatly prolong the time
of cooling to the same surface-gradient, beyond what
it would be with these qualities increasing continuously
with temperature. For the simple case of conductivity
assumed to increase in the same proportion as specific
heat, Prof Perry has himself since given in a later
communication (Nature, February 7, pp. 341-342) the
necessary correction of his previous mathematics : and
in an example of his own choosing (50 per cent, aug-
mentation of each quality per loo' elevation of tempera-
ture), he now finds 121 times my estimate for the age of
the earth, instead of 441 times as by the formula which
he used in his first article.

When the ratio of thermal conductivity to specific heat
per unit bulk varies with the temperature, the problem
of secular cooling presents mathematical difficulties
which, so far as 1 know, have not been hitherto attacked ;
but I find it quite amenable to analytical treatment, and
I hope before long to be able to offer a paper to the
Royal Society of Edinburgh on the subject, as an appendix
to my original paper " On the Secular Cooling of the
Earth," published in its Transactimis (1S62,. I have
already worked out numerically two cases, in one of
which both conductivity and specific heat increase with
temperature, and in the other the specific heat increases
with the temperature but the conductivity is constant.
The first of these is at present only interesting as a
mathematical exercise because, according to present
knowledge, it is moie probable that the thermal con-
ductivity decreases than increases with increasing
temperature. To the results of the second I shall refer
later as substantially helping us towards a revised
estimate of the time which has elapsed since the con-
solidation of the earth.

Twelve years ago, in a laboratory established by Mr.
Clarence King in connection with the United States
Geological Survey, a very important series of experimental
researches on the physical properties of rocks at high
temperatures was commenced by Dr. Carl Barus for the
purpose of supplying trustworthy data for geological
theory. Mr. Clarence King, in an article " On the .\ge of
the Earth '' \>\x\>\\^\ie.A\n\.\\e. American Journal 0/ Science
(vol. xlv., Jan. 1893), used data thus supplied, to estimate
the age of the earth more definitely than was possible for
me in 1S62 with the very meagre information then
available as to specific heats, thermal conductivities, and
temperatures of fusion. I had taken 7000' F. (387 1' C.)
as a high estimate of the temperature of melting rock.
Even then I might have taken something between
looo' C. and 2000 C. as more probable, but I was most
anxious not to //«rtVr-estimate the age of the earth, and
so I founded my primary calculation on the 7000' F. for
the temperature of melting rock. Now we know from the
work of Carl Barus {Phil. Mag. 1S93, first half -year, pp.
1 86, 1 87, 301-305) that Diabase, a typical Basalt of very
primitive character, melts between iioo C. and 1170'
and is thoroughly liquid at I200^ The correction from
3871 C. to 1200' or I 322 of that value, for the
temperature of solidification, would, with no other change
of assumptions, reduce my estimate of 100 million
to I (3-22)- of its amount or a little less than ten million

NO. 1323. VOL. 5 l]

440

NA TURE

[March 7, 1895

years ; bat the effect of pressure on the temperature of
solidification mu-t also be taken into account, and Mr.
Clarence King, after a careful scrutiny of all the data
given to him for this purpose by Dr. Barus, concludes
that without farther experimental data " we have no
" warrant for extending the earth's age beyond 24 millions
" of years."

By the solution of the conductivity problem to which I
have referred above, with specific heat increasing up to
the melting point, as found by Riicker and Roberts-
Austen and by Barus, but with the conductivity assumed
constant, and by taking into account the auginentation of
melting temperature with pressure in a somewhat more
complete manner than that adopted by Mr. Clarence
King, I am not led to ditier much from his estimate of
24 million years. But, until we know something more
than we know at present as to the probable diminution,
or still conceivably possible augmentation, of thermal
conductivity with increasing temperature, it would be
quite uninteresting to publish any closer estimate.

In the latter part of .Mr. Clarence King's paper on the
" Age of the Earth " the estimates of the age of the sun's
heat by Helmholtz, Newcomb, and myself, are carefully
considered, and the following sentences with which the
paper is brought to a conclusion will, I am sure, be
interesting to readers of N.atlkf. : — " From this point of
" view the conclusions of the earlier part of this paper
"become of interest. The earth's age, about twenty-four
"millions of years, accords with the fifteen or twenty
"millions found for the sun.

" In so far as future investigation shall prove a secular
"augmentation of the sun's emission from early to pre-
"senttimein conformity with Lane's law, his age may
"be lengthened, and further study of terrestrial conduc-
"tivity will probably extend that of the earth.

" Yet the concordance of results between the ages of
"sun and earth, certainly strengthens the physical case
"and throws the burden of proof upon those who hold
" to the vaguely vast age, derived from sedimentary
" geology." ' Kelvin.

NOTES.
In addition to Lord Aberdare, the Royal Society has to
mourn the loss of two more of its Fellows. Sir Henry Rawlin-
son, the distinguished Orientalist, died on Tuesday, in his
eighty-fifih year. He was elected into the Society so long ago
as 1850. Sir William Savory, who died on Mond.iy, at the age
of sixty-nine, was admitted eight years later.

We have also to announce the death of Dr. IJ. H. Tuke,
well known for his works on psychological medicine.

It is announced in the Britiih Medical jfournal that Dr.
.\rmand Ruffer has tendered his resignation of the post of
Director of the British Institution of Preventive Medicine.

When the news of Prof Caylcy's death reached America,
American mathematicians were not slow in expres'<ing sym-
pathy with their En|{lish brethren. We are informed thit —
" In that great American University, the Johns Hopkins, in
which, not many year* ago. Prof. Sylvester and I'rof. Cayley,
at the same time, gave instruction in advanced mathematics,
the death of Prof. Cayley was the occasion of universal
mourning, and all was appropriately draped with black."

It appears from a correspondence between the Board of
Trade and the Electric Lighting Committee of the St.
Pancras V'cttry, that Major Cardew, the electrical adviser
of this department, has discovered, during his investigations
into the recent explosions in the street boxes used
for electrical supply in St. I'ancras, that a remarkable

NO, 1323, VOL. 51]

deposit on some of the insulators contained a considerable
quaniily of the metal sodium. The presence of this meta)
appears to be so grave a source of danger, and to afford so
reasonable an explanation, in connection with the accumulation
of escaped co.il gas, of the several explosions which have
recently occurred, ihat the Board of Trade intends to in-
vestigate the causes of the deposit of this substance with a
view to iis prevention, and in this investigation they have
asked for the assistance of the Royal Society and of the In-
stitution of Electrical Engineers.

Prof. Charles Stew.\rt will deliver a course of six lec-
tures on " The Internal Framework of Plants and Animals," at
the Royal College of Surgeons, Lincoln's Inn Fields, on
March 11, 13, 15, 18, 20, and 22, at five o'clock. Admissiot>
to the lectures can be obtained on presentation of visiting card .

A CORRESPO.VDEN'T, writing from Brooklyn on February 16,
says : — The severity of the weather and depth of snowfall
throughout the southern United Slates for the past few days are
unparalleled. On ihe 14th inst. ihe temperatuie at Abilene,
Texas, was 15°, and in the State of Georgia it ranged about
9° lower than in New York city. Yesierdav there w.is snow
live inches deep in Atlanta, four inches at Darisn, three inches
at Thomasville, and two inches at Savannah, all in Georgia ;
two feet at Birmingham, .'Mabama; eight inches at New Orleans,
Louisiana ; six inches at Galveston, Texas, with snow falling
as far south as Corpus Christi. In many places there h.id never
before been snow enough to cover the ground to any me.isurable
depth.

Frost prevailed during the greater part of the past week in
nearly all paits of the United Kingdom, and in the northern
and midland districts the thermometer in the screen has on
several nights fallen as much .as 10 below the freezing point.
Snow has fallen over the greater part of the country, and in
Scotland the amount has been heavy. The type of weather has
been chiefly anti-cyclonic, and an area of low barometer read-
ings was for several days situated to the eastward of our islands,
so that strong and cold northerly winds were experienced over
the entire country. A correspondent at Dundee states that
the temperature in that district during the Lost two months
was unusually low. The average maximum temperature
of January and February was 36° '6, and the average mini-
mum, 24°'9, so that the average mean temperature for that
vicinity was about 3o'''7. The normal values publi-hed by
the Meteorological Council for Leith, a little more to the
south, give 39°'5 as the average mean temperature for the two
months.

Prof. M. MOllicr contributed an article to the January
number of Globus (Brunswick) on meteorology and the figure
of the earth, which contains much useful information upon the
subject of atmospheric circulation, and the results of the
author's own investigations. He points out very clearly the
effects of the earth's rotation and of the polar compression on
the motion of the air, and strongly opposes the theory of
equatorial and polar currents as propounded by Dove and his
adherents. He explains the enormous forces that would be
required to transpose a kilogram of air from the pole to the
equator, and shows that the motion of a particle closely re-
sembles that of a ball which is kept in circular motion on a re-
volving plate by a juggler, the rapid rotation of the plate, and
of the earth, acting similarly on boih ball and air. and keeping
both moving in comparatively small and nearly closed curves.

Dk. a. Cancani notes the existence of two systems of undu-
lations in the Constantinople earthquake of July 10, 1894, one
propagated with a velocity of 4 9 km. per second, the other
with a velocity of 23 km. per second (Rend, dell' Ace. dii

March 7, 1895]

NATURE

441

Lincei, December l6, 1894). The latter estimate is obtained
from the times furnished by magnetic or astronomical observa-
tories, possessing instruments capable of recnriing long-period
oscillations only. The instruments of the Italian seismic ob-
servatories, on the other hand, registered the rapid movements
travelling with the greater velocity, as well as the longer oscil-
lations, whose velocity is aijain found to be 2'3 km. per second.
Dr. Cancani remarks that these results agree with the theory
explained by him in a former paper {Ann. ilell' Uff. Ccntr. lU
Met. e Geod. vol. xv. 1893).

News has recently been received regarding the three at-
tempts made last year to extend our knowledge of the higher
mountains of Africa. The most important of these was Mr.
Scott Elliot's expedition to Ruwenzori, some of the preliminary
results of which he announced in a recent letter to Nature.
Mr. Scott Elliot seems to have found the higher slopes of the
mountain extremely trying to the native porters. Botanical
results of the highest interest may be expected from the work
of such an experienced African botanist. .\s Mr. Scott Elliot
did not succeed in reaching the highest zone in the mountain,
his description of its geology may be incomplete. He has,
however, announced one conclusion of the highest importance,
viz, the discovery of traces of the existence of glaciers, seven
miles below the existing snow-line. It will be remembered
that in a recent paper published by the Geological Society,

; Dr. J. \V. Gregory fully described similar glacial extension on
Mount Kenya. The difficulty, however, has heen felt that the

I same fact has not been recorded from Kilima Njaro, in spite of
the numerous visits to thit mountain. The glaciers there now
seem to be at their greatest extension. It is probable that
this is due to the fact that the peak with the existing glaciers
is of very recent date. The absence of moraines from the older

' peak appeared perplexing. Mr. Scott Ellioi's discovery, how-

' ever, shows that the greater glaciation of Kenya was not due
to a purely local cause, but to some change that affected the
whole region.

We have received a copy of the British Central Africa
'/'((■//(• (vol. i. No. 15), describing Capt. Mannin4's recen
asunt of Mount Mlanje, on October 22-25. The mountain ist
now well known irom the botanical collections made there by

] Mr. Whyte, under the direction of Mr. H. H. Johnston. Pre-
vious attempts to ascend it hid, however, failed through lack
of time. Capt. Manning's party do not appear to have found
the climbing very difficult. The summit is estimated at
9680 feet ; but we are not told by what method this was deter-
mined. Apparently it was only by aneroid. The parly were
helped up by a new method of roping, which ought to recom-

I mend itself to the Chamounix and Zermatt guides. They used

ja long loop of calico, which they called a " machila " : the
climber leant back at one end of it, six or eight stiong men

j pulled at the other. Probably in time, to " machila theMatter-

I horn " will be the regular thing in a Swiss trip.

The third expedition to which we have to refer, has unfor-
. tunately not been successful in its attempt to solve the mystery
of the reported snow-clad mountain which occurs between
Kenya and .Vbyssinia. The existence of this has been fre-
.^uently reported since it was first recorded by Abbadie as
Mount Wosho. It was hoped that Dr. Donaldson Smith's
expedition would have finally settled this question of the height
and position of this mountain. The expedition has, however,
been stopped by the Ahyssinians, and sent back to the Somali
frontier at Barri. His companion, Mr. Gillatt, has been com-
pelled to return home, but Dr. Smith has determined to con-
tinue the expedition. As the rainy season and unhealthy
country arc before him, and as such people as the Somali are
easily dispirited by a first failure, it is hardly likely that Dr.
NO. 1323, VOL. 51]

.Smith will reach Miunt Wosho. He proposes to strike south
for the Juba, and then westward across the Borana country to
Basso Narok (Lake Rudolph). The expedition has already
achieved some very interesting results, and if it succeed in its
traverse of the Borana country, it will have amply atoned for its
failure to reach its original goal of the Omo valley.

In an address to the United States National Geographic
Society, recently published in the National Geographic Magazine,
Dr. C. Hart Merriam discusses the influence of temperature upon
the geographical distribution of terrestrial animals and plants.
It is well known that in the northern hemisphere animals and
plants are distributed in circurapolar belts or zones, the boundaries
of which follow lines of equal temperature ; but difference of
opinion prevails as to the period during which temperature
exerts its restraining influence. Dr. Merriim opens new ground
in the address to which we refer. Physiological botanists have
long maintained that the various events in the life of plants, such
as leafing, flowering, cS:c. , take place when the plants have been
exposed to definite qaantitiesof heat, which are the sums total
of the daily temperatures abive a minimum (6° C. ) assumed to
tie necessary for function U activity, and are termed the physio-
logical constants oi l\\e particular stages. Dr. Merriam infers
from this that there must also be a physiological constant for
the species itself; and this species constant must be the total
quantity of heat required by a given species to complete its
cycle of development and reprodacti in. It folljws that not
only the mean temperature, bat .also the total quantity of heat
in particular zones must be considered in estimating the
influence of temperature upon the distribution of plants and
animals. Dr. Merriam has constructed a pair of isothermal
charts of the United Slates, of which one shows the distribution of
the total quantity of heat during the se.ason of growth and
reproduction (i.e. the sum of daily mean temperatures above
6° C), and the other the mean temperatures during the six
hottest weeks of the year. B)r conparing these with a bio-
geographical chart of the same region. Dr. Merriraan concludes,
from the striking coincidences which occur, that animals and
plants are restricted in northward distribution by the total
quantity of heat during the season of growth and reproduction,
and in sou'hward distribution by the mean temperature of a
brief period during the hottest part of the yeir. The anomalous
intermingling of boreal ami austral types which occurs over an
extensive area of the Pacific coast of the United States becomes
explicable by the establishment of these principles, for here
alone is a low summer temperature combined with a high sum-
total of heat — the two conditions which permit extensive
mixture in the same region of northern and southern types.

A CASE of dual brain action, presenting points of special
interest, both in physiology and psychology, is described in
'■train (Part Ixix.) by Mr. L. C. Bruce. The patient who
formed the subject of observation varied considerably in his
mental condition, and the most obvious phenomena observed
during these changes were thit in one condition he spoke the
English language, and in the other the Welsh language. When
in the former state, he was the subject of chronic mania. He
was right-handed, and exhibited a fair amount of intelligence.
He remembered clearly things he had noticed in previous
English periods, but his memory was a blank to any that
occurred during the Welsh stages. He wrote by preference
with his right hand, his letters were fairly legible, and he wrote
from left to right. If asked to do so, he would write with the
left hand, but then produced mirror writing, traversing the
paper from ri^ht to left. When in the Welsh stage, however,
he was left-handed and the subject of dementia. His speech
was almost unintelligible, but what could be understood was in
the Welsh language. In this stage he had no idea of English,.

442

NA TURE

[March 7, 1895

and his mental and physical conditions altogether were the
reverse of what they were in the English stage. From these
objervations, Mr. Bruce is led to believe that "the cerebral
hemispheres are capable of individual mental action, and that
the mentally active cerebrum has a preponderating influence
over the control of the motor functions, the patient living two
separate existences during the two stages through which he
passes ; the mental impressions received during each of the^e
separate existences being recorded in one cerebral hemisphere
only." If the cerebral hemispheres did not act independently,
it is difficult to account for the patient's ignorance of events
which happened to him in the Welsh stage when he passed into
the English condition.

A NOTE on the electrostatic capacity of resistance coils wound
in the ordinary way to avoid self-induction, is published in the
Comples rciiJus (February il). The author (M. J. Cauro)
has experimentally determined the electrostatic capacity of
coils wound in several different ways, using for this purpose
a Wheatstone's bridge arrangement with a commutator
similar to that used by Ayrton and Perry in their secohmmeter.
By comparing coils of practically the same shape and resistance
the author finds that the errors due to capacity may, in the case
of coils containing a large number of turns, be considerable
when the ordinary double method of winding is .idopted, but
these errors are considerably reduced if the method of winding
proposed by M. Chaperon is employed. The best results of
all are obtained by winding the two wires in alternate layers,
always slatting from the same end of the bobbin, the wire
being brought back parallel to the axis of the coil. For
instance, with coils having a resistance of about 14,000 ohms
and about 9500 turns, the three methods of winding give
apparent self-induction (due to capacity) of - 1 79, - o'27
and -o'i6 respectively. In order to make sure that the values

obtained were really due to capacity, the author placed bundles
of fine iron wire inside the difi'erent coils. The results

obtained in this case were the same as those obtained without
any iron core. By altering the connection of the two wires in

the coil wound in the ordinary manner, so that the current

tiaverscd the two circuits in the same direction, the self-
induction was found to be 0'13. Thus by winding the wire-
double, the error due to electrostatic capacity was about
twelve times as great as the error to eliminate which this
method of winding was adopted.

Two volumes recently added to the comprehensive Aide
Mcmoire series, published jointly by Gauthier-Villars and
Mujon, Paris, are : — " Appareils .\ccessoires des Chaudiires a
Vapeur," by MM. Dudebout and Croneau, and " Trailc des
Bicyclei et Bicycleltes " by Dr. C. Bourlet.

Thk names of the members of the electrical and kindred
industries throughout the world are contained in " The Universal
Electrical Directory," published by Messrs. II. Alabaster, Gate-
house, and Co. For simplicity and facility of reference the
names are divided into four groups — namely, lirilish. Con-
tinental, American, and Colonial, which are .igain subdivided
into alplial)etjcal and claisified sections. There are nearly
twenty-one thousand names in all, or two thousand five hundred
more names than were given in the Directory foi 1894.

Amono the forthcoming books to be published by Messrs.
J. and A. Churchill, the following are announced to appear at
an early dale :— " A Manual of iiotany " based on that of the
late Prof. Bentley, vol. i., " Morphology and Anatomy,"
enriched with a large number of new illustrations, by
Prof. J. Keynoldi Green; "Elements of Health, an
Introduction to the Study of Hygiene," by Dr. Louis C.
Parkes ; and "Mental Phyjiology, especially in its relation to
Mental Disorders," with illustralioni, by I)r. T. IJ. Hyslop.
NO. 1323. VOL.51]

A VALUABLE work on the climatology of Africa, and 011 the
distribution of disease in that conlinent, has just appeared. It
is entitled " Tropic.il Diseases in .Vfrica," by Dr. K. W. Felkin>
and is published by Mr. W. F. Clay, Edinburgh. The volume
's based upon a lecture delivered at the .African Ethnological
Congress held at Chicago in 1S93, and contains, as an appendixi
a paper, read before the Budapest Congress last September,
on a new method for graphically illustr.Aling the geographical
distribution of disease. The book forms an important addition
to the literature upon tropical disease in Africa.

Men of science are indebted to the beneficent provisions of
the Smithsonian Institution for the generous distribution of
scientific literature. A publication of special value to chemists
is the " BibliOijraphy of Aceto Acetic Ester and its Deriva-
tives," by Mr. Paul H. Seymour, which, acting upon the
recommendation of the American Association's Committee on
Indexing Chemical Literature, the Institution has lately issued.
The bibliography is arranged in chronological order from 1840,
with author and subject indices appended. The outlines of

I memoirs are given, in order to show the scope of the originals.
Mr. Seymour deserves the gratitude of chemists for this time-

j saving bibliography, upon which he has evidently bestowed
much care.

1 Ani'THER paper prepared for the Committee on Indexing
i Chemical Literature, is " An Index to the Literature of Didy-
mium," by Dr. A. C. Langmuir, just distributed as No. 972
of the Smithsonian Miscellaneous Collections. The index con
lalns references to all the papers published on didymium, from
the discovery of the element in 1842 to the year 1S93. It
furnishes a striking illustration of the wonderful results .iccom-
plished by the use of the spectroscope in modern chemistry.
In addition to didymium, the following elements have now
been indexed: Coiumbium, iridium, manganese, titanium,
uranium, vanadium.

We note the publication of the BulUtin Mil^orologique of tlie
Imperial Observatory of Constantinople, for the year 1S94.
Although telegraphic observations have been published
in the Paris weather report, we believe that very few regular
observations from Constantinople have been received in tlii
country for some twenty years. The bulletin contains son
means derived from twenty-seven years' observations, whu I
show that the maximum shade temperature was 99 '5, in iSSS
and the minimum, 17''2, in 1S69. The average yearly rainfall
is 23 '3 inches, and the average frequency, eighty-six days.
Snow falls on about fifteen d.ays, and fog occurs, on an average, |
on filty-nine days. An appendix contains a list of the earth- (
quakes in the Ottoman empire during the year 1894.

A SKETCH of the attainments and life-work of Dr. T. li. Rake,
who died at Trinidad last .Vugust, is given in the Joiiriiat of
the Trinidad Field-Naturalists Club for December 1894. Dr.
R.ake was the superintendent of the Leper .'\sylum at Trinidad,
and presided over the Leprosy Commission. The reports issued
during his eight years' administration of the Asylum are of the
highest value, for he was well acquainted with bacteriological 1
methods of research, and he put on record numerous observa-
tions referring to the leprosy b.icillus. He was not, however, j
only a high authority on leprosy, but an enthusiastic and kecnd
observer of natuie. At the time of his death he was the Prew-j
dent of the Trinidad Field-Natur.ilists Clul), the members ofi
which will remember him for many years to come. An excel-q
lently reproduced portrait of Dr. Rake forms the frontispiece'!
of the Jturnat containing the very appreciative obituary
notice.

A moni;meNI Io the humanitarian spirit of the members ol|
the Mulhouse Association pour prevenir les .Accidents dc

March 7, 1895]

NATURE

443

Fabriques is afforded by a ponderous volume, the second edition
of which has been received from the Association. The volume
is entitled "Collection of Appliances and Apparatus for the
Prevention of Accidents in Factories." It is illustrated by
thirty-seven finely-drawn plates, and the text is printed in
French, German, and English. The London agents are Messrs.
Dulau and Co. What strikingly indicates the high motives
which actuate the Association is that the volume is published
at the price it cost to reproduce. The one object of publication
is to spread the knowledge, and encourage the adoption, of the
numerous appliances devised for the prevention of accidents
from machinery. The factory inspector and manager, the
mechanical engineer, and all others who are concerned in the
construction and use of machinery, should see this very useful
volume.

We have received the first two numbers (1892-1893) of the
yearly Bulletin of the Geolo^i'.al Iiistitittion of the University
of Upsala. This is a publication that should be of great
interest to all British geologists whose work lies among the
Lower Palaeozoic rocks, since on those strata Swedish researches
have thrown so much light. Among the contents are two
papers by C. Wiman, on the structure of Graptolites ; strati-
graphical papers, by the same- author, and J. G. Andersson ;
petrographical and mineralogical papers, by Prof. Nordenskiold
and H. Sjijgren ; and others. Nine plates in all, illustrate
the numbers. The papers are all in either English or German
I'rench is the only other language permitted) ; this will be satis-
factory to those British geologists who have found the
Swedish language a serious barrier to the study of important
Ideological papers in the past. We may add that the Bulletin
will be sent, not only to all geological institutions, but also
t > all private workers who send their publications regularly in
exchange.

Among the new editions received during the past week, is
Ihe second edition of the "Introduction to Physiological
Psychology" (Swan Sonnenschein and Co.), translated from
!he revised and enlarged second German edition of Dr.
Trichen's work, reviewed in these columns four years ago (vol.
xliv. p. 145). The chief addition is a chapter upon the
emotional lone of the ideas. Another new edition (the fourth),
ust received, is "A Treatise on Elementary Trigonometry"
l^ongmans. Green, and Co.), by Dr. John Casey, F.R. S.,
edited by Prof. P. A. E. Dowling. This little work has found
favour among many teachers and students, and the nuw issue
should be even more popular. Dr. W. \\. Besant's "Conic
Sections" (George Bell and Sons) has reached a ninth edition.
1 lie articles on reciprocal polars have been expanded into a
separate chapter, and a chapter on conical projections has been
inserted. Two other books, which maybe included among new
issues, belong [to the handy series of Economic Classics pub-
lished by Messrs. Macmillan and Co. One consists of select
chapters and passages from Adam Smith's "Wealth of
Nations " ; the other contains the first six chapters of Ricardo's
" Principles of Political Economy and Taxation."

Messrs. Swan Sonnenschein and Co. have in the press
an important work on the Indian Calendar, written by Mr-
Robert Sewell, in collaboration with Mr. Sankara Balkrishna
Oikshit. The work contains complete tables for the verification
of Hindu and Muhammadan dates for a period of 1600 years
(a.u. 300 to 1900), and forms an attempt to carry out in prac-
tical form the exact fixation of the astronomical phenomena on
which the Hindu Calendar depends, and without which no con-
version of dates into European reckoning can be safely relied
upon. It embraces the whole of India. The calculations have
been based on the general tables published by Prof. Jacobi, of
Bonn, checked and enlarged by Mr. S. Balkrishna Dikshit.
NO. 1323, VOL. 51]

The precise position of sun and moon at sunrise on the meridian
of Ujjain on the first day of each year of the Luni-solar
Calendar during the period referred to is given, and for the
Solar Calendar the moment of the sun's passing the first point
of Aries in each year is entered in time reckoning. Full details
for the addition and suppression of months in the intercalary
Luni-solar years are provided; and where necessary the cal-
culations have been made for true as well as mean intercalations.
The solar phenomena have, moreover, been computed by both
the .\rya and Surya Siddhcintas. It is hoped that the volume
will form a standard work of reference for chronologists, as well
as for all courts and offices in India.

The additions to the Zoological Society's Gardens during
the past week include a Giraffe (Giraffa camelopardalis, 9 ) two
Sable Antelopes {Hippotragus niger, i 9 ) two Brindled Gnus
(Connoch.iles taurina, i 9 ), a Levaillant's Cynictis (Cynictis
penicillata) from South Africa, two great Eagle Owls (Bubo
maximus), European, purchased ; two Rock-hopper Penguins
[Eudyptes chrysocome] from New Zealand, four Black Franco-
lins (Franeolinus vulgaris) from India, a Robben Island Snake
{Corondla phocarum) from South Africa, deposited ; a Black-
headed Gull {Larus ridibundus), British, presented by Mrs.

Rees Davis; a Buzzard (Biiteo, sp. inc.) from South

Africa, presented by Mr. J. E. Matcham ; a Robben
Island Snake (Coroiiella phocarum) from South Africa,
presented by Dr. Arthur D. Bensusan.

OUR ASTRONOMICAL COLUMN.

SrECTROscopic Measures of Planetary Velocities. —
A new feature in the application of the Doppler-Fizeau prin-
ciple has been recently brought forward by M. Deslandres
(Comptes renJus, Feb. 25). It is to the effect that when we
observe the spectrum of a body shining by reflected light the
displacement of the lines due to movements in the line of sight
depends upon the movement of the body with respect to the
original source of light, as well as on its movement with regard
to the observer.

The truth of this principle is demonstrated by an investigation
of the rotation of Jupiterwhich M. Deslandres has carried out with
his usual skill. The equatorial linear velocity of the planet is I2'4
kilometres, and the difference of the velocities of the two extreme
edges 24'8 kilometres ; actual measurements of the spectrum
photographs taken near opposition, however, show a relative
movement of twice this amount. The best results appear to
have been obtained by allowing the equator of the planet to lie
along the slit of the spectroscope, in which case the eflect of the
displacements at different distances from the centre is obviously to
produce an inclination of the lines of the planet spectrum to the
lines of the comparison spectrum, and this inclination affords the
means of determining the velocities. Ttiis method has the
advantage that the effects of small movements of the image on
the slit during the long exposure necessary with the great dis-
persion employed are of little consequence ; movements in
declination will have no effect on the inclination of the lines,
and movements in right ascension will only tend to make them
somewhat more diffuse.

M. Deslandres points out that the new principle may possibly
have many important applications in connection with planetary
velocities, among whicn he specially mentions the determination
of the rotation period of Venus, and even possibly of the solar
parallax, the latter being derived from the radial velocity of
Venus. M. Poincarc shows that M. Deslandres' results are
quite in accordance with theoretical considerations.

The Satelli rES or Mars.— Prof. Campbell, of the Lick
Observatory, took advantage of the recent opposition o( Mars
to secure a long series ot micrometric measurements of the
satellites with the 3-foot telescope (Astr. Journal, No. 337).
The reduction of the observations of Phobos shows that the
eastern elongation distance was nearly a second greater than
I the western, whereas Hall's observations in 1877 showed that
the distance at western elongatipn was then about 2"'2 greater

444

NA TURE

[Makcii 7, 1895

than the eastern. " If the orbir had remained unchanged from
1877, ihe western distance in 1894 should have been about T 'S
greater than the eastern. The change of ne.irly 2"'S was
evidence ol a marked transformation of the oibit during the
years 1S77-94. The line of apsides has probably revolved
owing 10 a polar compression of the planet." The observa-
tions also appear to indicate a similar transformation of the
orbit of Deimos, but the evidence is not quite so conclusive.

Both satellites are about 6 minutes behind Marth's etihemeris,
so that the adopted values of their periodic times require slight
<orTeclion.

Eclipse OF thi: Moon, March ii.— The following par-
ticulars with regard to the total eclipse of the moon on the
momiDg of Monday, March 1 1, may be of interest : —

G. M. T.
h. m.

First contact with penumbra o 58'4

,, ,, shadow I 5r9

Beginning of total phase ... ... ■■. 2 51 8

Middle „ „ 3 392

End „ ,, 4 2' 6

Last contact with shadow 5 243

,, ,, penumbra ... ... ... 6 20 o

The first contact with the shadow will occur at 127' from Ihe
north piinl of the moon's limb towards the east, and the last
contact at 69° towards the west, in both cases for the direct
image as seen with the naked eye. The magnitude of the
eclipse (moon's diameter = unity) will be I "619.

The moon will be seen in the shadow at places between
longitudes 5h. E. and I2h. W. Among the principal stars
occulted during the eclipse will be 83 Leonis. mag. 7 5, which
will disappear at 2h. 17m. at an angle of 95° and reappear at
3h. 12m. at an angle of 33S' ; and - Leonis, mag. 5'0, which
will disappear at 2h. 56111. at 86°, and reappear at 3h. 43m. at
an angle of 345° ; the angles being reckoned from north
towards east.

THE NILE}

T AM to speak to you to-night of the Nile, and I think I may
■*■ fairly say it is the most famous river in all the world
famous through all Ihe ages, for the civilisation that has existed
on its banks : famous for its mystic fabulous rise, about which
so many sages and philosophers have pindered ; f.imous for its
length, traversing one-fifth the distance from pole to pole;
famous, and app.irenlly destined to be famous, for the political
combinations that ever centres around it. But I feel 1 must
begin by an apology, for now that Egypt has come so com-
pletely within the tourist's range, probably many of my hearers
have seen more of the Nile than 1 have.

n a foreigner were to lecture to his countrymen about the
river Thames, and were to begin by informing them that he had
never been above Greenwich, he might be looked ui)on as an
impostor ; and perhaps I am not much better, for I have never
been higher up the river than PhilK, 610 miles above Cairo.
For information regarding anything higher up, I must go, like
you, to the works of Speke, Baker, Stanley, ami our other
great explorers. I shall not, then, detain you to-night with any
elaborate account of 'his upper portion of the river, but will
only remind you briefly of that great inland sea, the Victoria
Nyanii, in extent only a little less than the American Lake
Superior, traversed by the equator, and fed by many rivers,
some of ihem taking their rise as far as 5 .S. lat. These rivers
form the true source of the Nile, Ihe mystery only solved in the
present generation.

The outlet ol this great Ltke is on its north shore, where
Ihe river rushes over the Kipon Falls, estimated by Speke
at only 400 or 500 feet wide, and with a drop of 12
feet. Thence the river's course is in a north-west direc-
tion for 270 miles, lo where it thunders over the Murchison
Kails, a cliff of 120 feet high. Soon after that it joins
Ihe northern end of Baker's Lake, the Albert Nyanza, but
only lo leave it again, and to pursue its course through a
grcal marshy land lor more than 600 miles, lo where the Bahr
4,azelle joint it from the wot ; a little furtlicrdown the great
Saubat tributary comes in on the east. This is the region in

' A l«cti]r« delivered »l the Royal Intlilution, on January 35, by Sir Colin
Scott. MoncriefT.

which the river is obstructed by islands of f1.\itipg vegetation,
which, if checked in their course, at last block up its whole
width, and form solid obstructions known as saiiJs, substantial
enough to be used as bridges, and obstacles, of course, to navi-
gation, until they are cleared away. The waters of the Saubat
are of veiy light colour, anil tinge the whole river, which, above
lis junction, is green and unwholesome, from thr lori^ chain of
marshes which it traverses. Hence it is called the \\ tiiie Nile.
600 miles further brings us to Kh.ii oum, where the Blue Nile
irom the Abyssinian mountains joins it, and at 200 miles still
further to the north it is joined by the .\tbara river, also from
Abyssinia, a torrent ra'her than a river.

Baker gives a gtaphc account ol how he was encamped by the
dry bed of the Ath.ira on June 22, 1861. T^e hea' was intense,
thecountry was parched with drought. Duiing the night the cry
went forth that the floods were coming, and in ihe morning he
found himself on the banks of a river, he says, 500 yards vsideand
from 15 to 20 feet deep. All nature h.id sprung into life. A
lit'le north of the ju' ction of the .A. bara is iterber, whence you
will remember is the short C"t to Snakin in the Ked Sea, which
so many thought wonl I have been the tr' e route for our Army
to lake in relieving Cordon. From Khartonm to Assouan is a
distance of 1 100 miles of river, dnring whiih it makes two
immense curves, for on a straight line the distance is not hall so
much, and it is in this pan of its course that i p.T-srs over the
six great >atar.icts 01 rapids which I. lock all ordinary navigation.
The first or furthest norih cataract is just above Assouan, a
dis ame of 750 miles from the Medite>rane.in, through the
country known as Egypt. From the junction of tt'e A' bara to
its mouth in the Meditenanean, a distance .f 16S0 miles, the
Nile receives no tributary. On the contrary, duri g every mile
of i s course its waters are diminished I'y evap'^ration, by
absorpti n, and by irrigaion. The riv.r gns less and less as
it flows Ihrouiih this rainless land, and its mavimum volume is
to be found during the flo ids at the junction of the A'bara, and
at other seasons at Khartoum, 1875 miles from the Mediter-
ranean.

The whole His'ance by river from the Victoria Nyania to
the sea is about 3500 miles. It may not be easy to derive
any clear impressiim from this hare recital of mileage. Let me
try to convey to you in some other wa>s the idea ol the length
ol the Nile. Standing on the bridge at Cairo, I used to reflect
that I was just about half-way between the source of the Nile
and the While Sea. Or 10 put it another way : if we could
suppose a river crossing our English Channel, a-d that Ihe I
Thames should find its outlet in the ICuphrates and the Persian |
Gulf, that river would be about as long as the Nile. 1

In this short sketch of the course of the Nile, I must not j
forget to mention one inieresiing feature. About 40 miles
south of Cairo, the low Libyan chain of hills which bounds the
Nile valley on the west is broken by a gap, through which the '
waters of the river can flow, and beyond this gap lies a saucer
shaped depression called the Fa) urn, of abiut 400 square mile
in area, sloping down to a lake of considera'ile size, the surfan
of whose waters stands about 13J feet below that of the sea.
This lake is known as the Birket el Kurim.

From Ihe lime of the earliest Egyptian records, this province
of the Fayiim was famed for its fertility, and lo Ihe Kgyptiar.
taste for its delighiful climate. Many of the most prcciou
monuments of antiquity have been found in the Fa)iiiD. Tl-
famous Labyrinth is supposed to have stood just at its entrance
and what has excited most interest lor the engineer in all
times, it is here that Herodotus places that wonderful lake
MiL'is, which receiving for half the year the surplus supply of |
the Nile, rendered it back again in irrigation to Lower Egyptl
during the other half. Where this lake actually was, has
excited discussion since any attention has been paid to ancient I
Egyptian history. It seems preily clear that in earlier day-
the iiiket el Kuriin was of much greater proportions than it i
now, but how it cvrr could h.Tve been large enough lo allow
of its waters fl .wing back into Ihe Nile valley when the rivet
was low, wiilioul at the same lime drowning the whole Fayuni.
is not very clear.

Now, what are Ihe functions of a great river, what arc tli(
offices which it renders lo man? And first of all, M least ir
this latitude, we would mention the carrying off to the oceat
I of the surplus waier that descends from the skies. Nobly doc
Ihe Nile fulfil this duly; but with this enormous qualificalinn
that it transports the water from tracts where there is too much
and carries it all free of cost, not to waste it in the sea, but I'

NO. 1323, VOL. 51]

March 7, 1895J

NA TURE

445

bestow it on tracts where il is of priceless value, more thin
taking the place of rain in watering the fields.

The next functi m of a river is to f ■rm a hisjhwiy throue;h the
land, and for most of it* course ihc Nile fulfils this duty well
too. Gordon considered it possihle for steamers to ascend the
Nile during the II loiU from its m mth to the Fola ra lids a dis-
tance of ahoiit 3040 miles ; "lut at other seasons, the sixcitaracts
cannot be passed. Leaving out the iioo miles which they
occupy, there is an unbroken 750 miles In the lower, and nearly
1200 miles in the upper river. I cannot look on it as probable
that it will ever pay to make navigable canals and locks round
these cataracts, as it would entail so much hard rock-cutting.

Another function of a river is to promote industry by the em-
ployment of its water-power. We know how valuable is ihis
power eN'en in England, and how much more in countries like
.Switzerland, where it abounds, and on the great livers of
America. Excf-ptinga fewvery rudewooden " heels in tlieFayi'rn,
I do not know, through all the annals of the past, of a single
water-wheel ever turned by the power of the Nile. But that
power exists to an almost unlimitrd cx'ent. .\nd may we not
prophesy that some day in the future, when ihit long stretch of
Nubian cataracts has fallen into civilised hands, and when we
know how to transmit electric energy with economy, that ilien
our descendants will draw wealth to K^ypt from its chain of
barren cataracts?

As a drainage outlet to a continent, as a long highway, as a
source of power, the Nile is great ; but not so much so as many
other rivers. Its unique pr sition is due to the benefit it confers
on Egypt in turning it from being a desert into being the richest
of agricul uial lands, suppor'ing wi'h ease a population of about
six hundred to the square mile. Herodotus truly said Egypt is
the gif of the Nile. It mor^ than supplies the absence of rain,
and this it does, first, by the extraordinary regularity with which
it rises and falls ; and secondly, by the fertilising matter which
the wati-rs carry in suspension, and bestow upnn the land.
Imagine what it would be to the English farmer if he knew
exactly when it would rain and when it would be sunshine.
When the Irigaiion Department of Egypt is properly admin-
istered, the Egyptian (armer possesses this certainty, and he has
(his further advantage — that it is not merely water that is poured
over his lands, hut, during nearly half the year, water charged
with the finest m inure.

According to the early legend, the rise of the Nile is due to
the tears shed by Isis over the t'lmb of Osiris, and the texts on
the Pyramids allude to the night every year on which these
tear-drops fa!). The worship of Isis and Osiris has long passed
away, hut to this day every native of Egypt knows the LaiUt
en Nttktah^ the night in which a miraculous drop falls into the
river, and causes it to rise. It is the night of June 17.
Herodoius makes no allusion to this legend of Osiris. In his
time, he says, the Greeks gave three reasons for the river's rise.
He believed in none of them, but considered, as the most
ridiculous of all, that which ascribed the floods to the melting
of snows, as if there c )uld possibly be snows in such a hot
region. It was many centuries alter Herodotus' time when the
snowy mountains of Central .Africa were discovered.

The heavy rains commence in the basin of the White Nile
during .\pril, and first slowly drive down upon Egypt the green
stagnant waters of that marshy region. These appear at Cairo
about June 15. About a fortnight later the real fl >od begins,
for the rains have set in in Abyssinia by May 15, and the
Blue Nile brings down from the mountains its supply of the
richest muddy water. It is something of the colour and nearly
of the consi^tency of chocolate, and the rise is very rapid, a;,
much sometimes as 3 feet per diem, for the Alhara torrent
having saturated its great sandy bed, is now in full flood also.
The maximum flood is reached at Assouan about September i,
and it would reach Cairo some four days later, were it not that
during August and Sep ember the water is being diverted on to
the land, and the whole Nile valley becomes a great lake. For
this reason the maximum arrives at Cairo about the beginning
of October. The rains cease in Abyssinia about the middle of
September, and the floods of the Blue Nile and Athara rapiiUy
decrease ; but in the meantime the great lakes and marshes are
replenished in the upper regions, and slowly give off their sup-
plies, on which the river subsists, until the following June.
\ early this phenomenon presents itself in Egypt, and with the
most marvellous regularity. A late rise is not mue than about
three weeks later than an early rise. In average years the
height of the flood at .Assouan is about 25A feet above the

minimum supply. If it rises 29 feet above this minimum, it
means peril to the whole of Egypt, and the irrigation engineer
has a hard time of it for two months. If the river only rises
20 feet above the minimum, it means that whole tracts of the
valley will never be submerged. Such a poor flood has
happened only once in modern times, in 1877, and the result
was more serious than the devastation caused by the most
violent exce^.s.

The mean flood discharge at Cairo is about 280,000 cubic
feet per second, the maximum about 400,000. The mean
lowest Nile is about 14,000 cubic feet per second at Cairo, but
some years there is not more than 10,000 cubic feet per second
pa sing Cairo in June, and within three months after this m.ay
have increased forty-fold.

Until this century, the irrigation of Egypt only employed the
flood wati-rs of the river, and it was this that made it the granary
of the world. No doubt, rude machines for raising Nile water
were used at all seasons and from all times. But by these it
was not possible to irrigate on a large scale, and in reality they
were only employed for irrigating vegetables or gardens, or
other small patches of land. It must not be thought that
the water of the flooded river is ever allowed to flow
where it lists over the lands. The general slope of the
vallev on each side is away from the river, a feature which
the Nile shares with all Deltaic streams. .Along each edge
of the river, and following its course, is an earthen embank-
ment, high enough not to be topped by the highest flood.
In Upper Egypt, the valley of which seldom exceeils six miles
in width, a series of embankments have been thrown up,
abutting on their inner ends against those along the river's
edge, and on their outer ends on the ascending sides of the
valley. The whole country is thus divided into a series of
oblongs, 'urrounded by embankments on three sides, and by the
slope of the desert hills on the fourth. In Lower Egypt, where
in ancient days there were several branches of the river, this
system was somewhat modified, but was in principle the same.
These oblong areas vary in extent from 60,000 to 3000 or 4000
acres, and the slope being away from the river, it is easy to cut
short, deep canals in the banks, which fill as the flood rises, and
carry the precious mud-charged water into these great flats, or,
as they are termed, basins of irrigation. There the water re-
mains for a month or more, some three or four feet deep, de-
positing its mud, and then at the end of the flood it may either be
run off direct into the receding river, or, more u-ually, passed off
through sluices from one basin to another, and ultimately back
into the river. In November the waters have passed oft", and
wherever a man and a pair of bullocks can walk over the mud,
and scratch its surface with a wooden plough, or even the branch
of a tree, wheat or barley is sown, and so saturated is the soil
that the grain sprouts and ripens in April or May ivithout a drop
of rain or any fresh irrigation. .And a fine crop is reaped. One of
our great brewers told me the other day, that when barley grown
in this country was spread in the mailing-house, about three per
cent, of it must be counted on as not sprouting and being dead.
If grain two or three years old was used, as much as twenty per
cent, would be found dead. With Egyptian barley, he said,
even after several years, you could count on every grain ger-
minating. The crop once reaped, the fields remain dry, and
crack in the fierce summer heat until ne.>:t flood comes on.

The tourist who only comes to Egypt to shun " winter and foul
weather," knows nothing of the majestic glories of the Nile flood.
The ancient Nilometer at the south end of the island of Roda,
just above Cairo, is one of the most interesting sights of the
place. The water enters from the river by a culvert into a well
about 18 feet square, with a graduated stone pillar in the centre.
On each side of the well is a recess about 5 ftet wide and 3 feet
deep, surinnunted by a pointed arch, over which is carved in
relief a Kufic inscription, and a similar inscrijtion is carried all
round the well, consisting of verses of the Koran. A staircase
goes dovin the well, from the slops of which the initiated may
read the height of the water on the pillar ; but they aie few in
number, and the hereditary Sheikh of the Nilometer, whose
duty it is to keep the record, is a person of some importance.
The Nilometer dates from A.n. 861, and I beli<ve in the
archives of Cairo may be found the daily record for looo years.

I need ha-dly tell you that uhen our I'.nglish engineers took
the river in hand, we established a number of gauges at Wadi
Haifa. Assouan, Cairo, and many other jioinis, on more scientific
principles than the venerable Nilometer of the Roda Island.

After the river has begun to rise, its height is daily chanted

NO. 1323, VOL. 51]

446

NATURE

[March 7, 1895

ihroagb the Cairo streets until it reaches i6 cubits on the gauge.
At this point the Khalig el Masri, the old canal that flows
throogh the heart of Cairo, is opened — up to this point it is
dry, and full or empty it is little mure than a sanitary abomin-
ation at present : but in former days it occupied an important
place, and when the Kile water was high enough to flow down
its bed, it wa^ looked on that ihe flood had fairly set in. and
that the kindly fruiis of the earth mi^ht be duly expected.

The head ol this canal is on the right bank of the river, just
south of Cairo. The water enters a channel some 30 feet wide,
with a high wall on its left, and a sloping bank on its right or
southern flank. Tlie water then flows under the pointed arch
of an old stone bridge. The bed of the canal is cleared so
that it would flow in at a gauge of about l:^\ cubits, but an
earthen bank is thrown acrcsi it about 4 feet higher.

There is no more interesting ceremony in Kgypt than the
annual cutting of the Khalig, as the opening ceremony is called.
It takes place between .\ugust 5 and 15. Days before prepara-
tions are being made for the festival. Tents with innumer-
able lamps are placed along the wall on the one side. Frames
for all manner of fireworks are ereced un the sand-bank on the
other side. .\ll ihe notables are there in full uniform, or in
canonical;. The Khedive himself, or his reprcienlative, the
Sheikh ul Islam (the highest dignitary of the Muhanimedan
faith), the Sheikh el Bekri, the Sheikh es Sadat, all the learned
scribes of the great university of the Azhar, the Cabinet
Ministers and Under-Secretaries, the Sirder of the Army
and his stafi, the Judges, and the Financiers.

The Egyptian troops are turned out, salutes are fired, and
about eight o'clock in the warm summer night the classes all
assemble under the gaily. lighted tents, the masses crowd round
the frames for the fireworks, the street is lined with harem
carriages full of closely-veiled figures, though it is not much
that they can see fiom their broughams. Out in the river, just
opposite the canal's mouth, is moored an old hulk of a certain
sea-going outline, which has been towed up from Uoulak during
the day, and is an emblem of the time when (he great republic
of Venice sent an envoy to witness the ceremony. This boat
is full of lamp«, and fireworks loo. As the night deepens the
excitement increases. The populace on the bridge and the
opposite bank are shouting, yelling, and dancing wildly round
the fireworks. On the other side arc the gay uniforms and
lighted tents, from whence we can look over the w all dow n on the
dark water, where you see brown figures plunging in and waist-
deep digging with their hoes at the embankment that blocks
the canal's mouth.

Long before midnight the fireworks have gone out, and left
the splendid stars to themselves ; the grandees have all gone to
bed, but the people keep up the revelry, and in the morning, by
7.30, every one has come bick. Then but little of the bank is
left uncut ; a few more strokes of the big hoes will do it, and
the brown skins and ihe brown water reflect the bright sunlight
from above. Then the Sheikh ul Islam solemnly thanks the
.\lmighty, .Mlah the All-powerful, the .*\ll-merciful. He im-
implores His blessing on the flood, and at a signal the bank is
cut, the waters rush in, and with Iheui a crowd of swimmers.
A bag of silver piastres is scattered among them, and the
ceremony is at an end.

There is a pretty legend, worth telling, of the cutting of the
Khalig. Amr, the Muhammedan General, look Cairo in a.d.
640. Long before then there had btcn a heathen ceremony,
and a virgin was yearly sacrficcd to the god of the river. When
the season came round, .\mr was called upon as usual to sacri-
fice Ihe girl He sternly refused. That year the Nile flood
wasa failure. You can fancy how the indignant heathen popu-
l.ilion must have raged ai the invader, and said, " We warned
you what would happen if you didn't propitiate the river gc«l."
Cannot we fancy, also, how .Vmi's wild Aiab soldiers must have
had their faith sorely tried, and how they must have felt pu/itlcd
i» to whether in this strange new country, with all those demon-
built temples and pyramids, obelisks and sphinxes, it might not
be as well to make friends of the local gods. Could Allah
really help them here? .Xgain the Nile flood came round.
This time surely Amr would sacrificcthegiti, and save the land.
No ; he would not. The people rose in rebellion. Amr stood
firm. liul he wrote to the Kalil (Jmar for orders (tJmar,
whose name you will remember has come down in history as the
destroyer of the Alexandrian library). Omar approved of his
conduct, but sent him a paper to throw into the Nile. On the
paper was written, "From Abd Allah Omar, I'rincc of the

NO. 1323, VOL. 51I

Faithful, to the Nile of Egypt. If thou flow of thine own accord,
flow not ; but if it be .\llah, the one the mighty, who causeth
thee to flow, then we implore him to make thee flow." .\mr
threw the paper into the water, and the Nile rose forthwith
exactly as it was wanted. .Since that day no girl has been
sacrificed ; but a pillar of earth is yearly left to be washed
away in the middle of the canal, called the bride or the girl.

Such, as I have briefly described it, was the irrigation of Fgypt
until this century, when it fell under the rule of Muhammed .\li,
a very sagacious and strong if a very unscrupulous ruler. He
saw that the country could produce far more valuable crops
than cereals. The European market could be supplied with
these from the fields of Europe, but Europe could not produce
cotton and sugar-cane. Egypt had the climate, had the soil, had
the teeming population ; but these crops required water at all
seasons ; nor would it do to flood the fields to any depth, for
just at the flood season the cotton crop is ripening. There was
plenty of water in the river ; but how was it to be got on to the
land ? Perennial irrigation was a fresh departure. As I have
said, the Nile rises about 25.I. feet. A canal then running 12
feet deep in flood has its bed 13J feet above the surface of the
Low Nile. Either the Nile water had to be raised, or the beds
of the canals had to be lowered, in order that one should flow
into the other, and after that the water had to be raised from
the canal on to the land. Muhammed -\li began by lowering
the canal beds of Lower Egypt, an enormous work considering
the great number of the canals ; and as they had been laid out
on no scientific principles, but merely to suit the fancies of
Turkish pashas or village sheikhs, and as those who had to ex-
cavate them to this great depth had only the slightest know-
ledge of levelling, the inevitable result followed — the deep
channel became full of mud during the flood, and all the exca-
vation had to be done over again. Incredible as it may seem,
this great work was done year after year. It was a great serf
population ; if they were not fighting Muhammed Ali's battles
in Arabia and Syria, they might as well be digging out the
canals. No one thought of paying or feeding the workmen.
The bastinado was freely applied if they attempted to run
away. If they died under the labour, there were plenty more to
come. But of course the work was badly done. The water
might enter the canal ; but as the bed was not truly levelled, it
did not follow that it would flow far. Then, as the river daily
fell, the water in the canals fell too, and lessened in volume as
the heat increased, and more was required. At last — in June,
perhaps — the canal was dry, and the cotton crop that had been
sown and watered, weeded and nurtured, since March, was lost
altogether.

Then some one advised Muhammed -\li to throw a dam
across the liver, and so raise the water, and the result was the
great liarragc.

About twelve miles north of Cairo the Nile bifurcates, and
finds its way to the sea, by the Rosetla and Damietta branches.
-\cross the heads of these two branches were built two stone
bridges, one of 71, the other of 61 arches, each 5 metres or
16 4 feet span. These arches were intended to be fitted with
gates ; by lowering which, all the water would be dammed up,
and diverted into three great trunk c.inals, taken out of the
river just above these bridges. One to the right or east of the
Damietta l>ranch was to supply water to all the Provinces of
the Eastern delta, one between the two bridges was to supply
the splendidly fertile central delta, the third to the left or West
of the kosetta branch was to water all the Western delta down
to Alexandria.

There was no intention of water storage at the Barrage,
but it was merely with the object of controlling the supply.
While there w.is water enough in the river, by closing the
gates it could be kept to a unilorm level, and sent down the
three trunk canals, fioji which it was to branch, into many
minor ones. .\s the river went down, gate after gate would be
closecl, and so a constant supply could be kept in the canals.
The idea was thoroughly sound. The execution was feeble.

Mougel Bey, the French engineer in charge of the work,
had no doubt many dilTiculties to contend with. The work
went fitfully on for many years, thousands of men being forced
to it one year, and carricl olT to a campaign the next. But at
last it was surticiently nnished to allow of an opening cere-
monial in 1861. Gales h.id been fitted into the Kosetta
branch arches, never into the Damietta.

The Central canal had been dug in tolerably satisfactory style.
The Weslei n canal, too, bad been dug, but passing I h rough a strip

March 7, 1895J

NATURE

447

of desert it had become very much filled up wiih sand. The
Eastern canal was dug some five miles, and then stopped. Of
course the lUrrage without these canals was useless. However,
they began to experiment with it, closing the gates on the Rosetta
side. It was intended to liold up 4i metres, or 14 feet 9 inches
of water. It never held up 5 feet, till in 1867, it cracked across
from top to bottom, on the Western side. An immense coflfer-
ilam was built round the cracked portion, and the water was
never held up again more than about 3i feet, while the work was
looked on as a deplorable failure. In 18S3, all hope of making
anything out of the liarrage was abandoned, and the Government
were on the point of concluding a contract with a company to
supply LoA'er Egypt with irrigation by means of an immense
system o( steam pumps, to cost ^^700,000 to begin with, and
.^250,000 a year afterwards.

That year there was a wretched serf army of 85,000 men
working at canal clearances for 160 days, unfed, unpaid. The
burden was nearly intolerable. The irrigation was all by fits
and starts. There was no drainage ; every hollow became sour
and water-logged. With waterways everywhere, there was no
navigation. In Upper Egypt things were better, as the system
was a simpler one. But when we came to look into them too, we
found great abuse, and on an average about 40,000 acres never
succeeded in obtaining water, though in the midst of abundance.

The Fayum had long been a much-neglected province,
though a most picturesque and attractive one. Frnm carelessly
allowing Nile water to How into the lake during the floods, it
had risen enough to swamp 10,000 acres of valuable land, and
this mischief we found still increasing.

Throughout the whole country drainage had been absolutely
neglected. And here I would point out that irrigation without
•drainage means the sure deterioration of the land sooner or
later. Considerable pains had been taken in Egypt to get the
water on to the land. No sr)rt of efifort had been made to get it
off. In a properly irrigated tract, between every two canals of
t^upply, there should flow a drainage channel ; the former
should follow as far as possible the highest lands, the latter
should follow the lowest. The canal gets smaller, till at last
it is exhausted, giving itself out in innumerable branches. The
drain, like a river, gets larger as it proceeds, being constantly
joined by branches. But if there be no drains, and if the canals
are laid out to flow into one another, so as to divide the country
into, as it were, a cluster of islands, you can understand how
the drainage water has no means of flowing off" into the sea,
and settles in unwholesome swamps. These we found prevail-
ing to an alarming extent in the rich provinces of the delta.
Such was the wretched state of Egyptian agriculture — the one
single source of the country's wealth — when Lord Dufferin laid
down the lines of the Entjiish administration, which have been
amplified and pursued ever since.

It was in May, 18S3, that I took charge of the irrigation
department in Egypt, having before then had some twenty
years' experience of similar work in India ; and I soon had the
inestimable advantage of being joined by a band of the most
indefatigable, energetic and able engineers, also from India,
with whom it was my great privilege and happiness to be
associated for the next nine years. I cannot talk too highly of
these my colleagues — men who knew their work and did it, who
kept constantly moving about in the provinces, badly lodged,
badly fed, denied domestic comforts, constantly absent from
their wives and families (they were all married men).

My friends, happy is the reformer who finds things so bad
that he cannot make a movement without making an improve-
ment. Happy the reformer who has as colleagues a stafl^ of
thoroughly loyal, duty-doing and cipable men. Happy the
reformer who is not ]iestered on all sides by the oflicious advice
of the ignorant. H.ippy the reformer who has behind him a
strong fjrave chief, as honest and truthful as he is strong. Such
rare happiness fell to me in Egypt with my noble colleagues,
and with Lord Cromer as our chief.

It is not my intention to enter into any details to-night of what
our work was in Egypt. I have lately spoken about that else-
where, and there would be no time to do so now. I must just
describe it generally.

On first arrival, I was pressed, both by English and French
men, to gi inio the question of the storage of the flood waters
ot the river on a large scale. I declined to do so, consider-
ing it would be time enough to think of increasing the quantity
of water at our disposal when we had profitably used all that
we already had, and while mighty volumes were daily flowing

NO. 1323, VOL. 51]

out to the sea, it could not be said that we were doing that.
The first great work to be studied was the Barrage. We were
warned on all sides to have nothing to say to it, as it was
thoroughly unsound ; but we felt sure we must either make it
sound or build an entirely new one, and we resolved on the
former. The work had failed because it was faulty in design,
the floorings and foundations not being sufficiently mas>ive,
and faulty in execution from the dishonest use of bad materials
and from bad woikmanship. The bed of the river consists of
nothing more stable than sand and alluvial mud for at least
200 feet deep. It was out of the question to think of getting
down to solid rock. It was not, as we thought, very safe to
excavate very deeply close to the existing works, so we decided
not to try it, but merely to strengthen and consolidate the
foundations, built as they were on sand. I have said that the
work consisted of two great bridges over the two branches of
the river. We could not shut up either branch entirely ; but
we decided to strengthen and complete one-half of each bridge
each season, which meant four seasons' work. While the river
was still in considerable flood each November, we began to
throw out great embankments of earth about 200 feet from the
bridge; one up stream, the other down-stream of it, beginning
at the shore end, and ultimately enclosing one half of the river
as in a pond. This used to take three months' hard work. Then
we pumped the water out of this enclosure, and laid bare the
very bed of the river. Then we laid a massive stone flooring,
5.\ feet thick, extending 100 feet up-stream, and as much
down-stream, of the bridge. This was very difficult and hard
work, it was kept going day and night, without intermission,
from March till the end of June. Then we cut great holes in
our embankments, cleared out our machinery, and prepared
for the arrival of the flood at the beginning of July. Each
year one-half of one bridge was finished, and the whole was
completed at the end of June 1S90.

In connection with the Barrage were completed the three
great canals to carry off all the river supply from above it. So
that practically now the Low Nile is emptied every season at
the Barrage and diverted into these canals, and no water at all
escapes to the sea. The natives wade everywhere across the
river north of this point. Since it was completed the Barrage
has given no trouble. It holds up every year 4 metres, or
13 feet of water. The three trunk canals were all supplied
with locks 160 feet by 28 feet, and adapted for navigation. The
whole of these works cost about ;^8oo,ooo. The annual in-
crease of the cotton crop, compared to what it was before 1S84,
is never less than two and a half millions sterling, which has not
been a bad investment for Egypt.

Turning to Upper Egypt, my colleague. Colonel Ross,
directed his attention very closely to the adjustment of canals
overlapping one another, passing under and p.assing over one
another ; so tnat in future I trust that with the feeblest Nile
flood it will be possible to pour water over every acre of the
land.

The question of drainage was very thoroughly taken up.
Twelve years ago it may be said that there were no drainage
channels in Egypt. Two years ago there were about 1000
miles of such channels, some with beds .as wide as 60 feet and
flowing deep enough to carry cargo boats, others with beds
only 3 or 4 feet wide. I am glad to say by these means large
tracts in Lower Egypt which had been abandoned as totally
ruined have now been restored to cultivation. The level of the
lake in the Fayum was reduced by 13 feet between 1885 arid
1893, ^"fl maA of the inundated lands around it have been again
dried.

I have already mentioned the cruel hardship of the corvee,
the serf army of 85,000 men who were employed in the canal
clearances from January to July, nearly half the year. I believe
this institution was as old as the Pharaohs, and it was not easy
to abolish it. Hut of course it went sorely against our British
grain. Little by little we got money to enable us to p.ay
our labour. By an annual outlay of ;f400,ooo this spring
corvee has entirely ceased since 18S9, and now the Egyptian
labourer carries out these clearances in as free a manner as his
brother in Middlesex, and gets paid for his work.

Having thus, to the be>t ot our powers, utilised the water in
the river flowing past us, we turned our attention to thestot.age
of the surplus waters. Withiout some such storage it is impos-
sible to increase the cultivation during the Low Nile. All the
water is used up. During High Nile there is always a grea
vole me escaping useless to the sea.

44S

NATURE

[March 7, 1895

There are two ways in which the water may be stored ; either
by thiowing a dam right across the river and forming a great
lake above i', or, if such a place can be found, by diverting the
flood water into some suitable hollow, and drawing it off
from there at the season of low supply, as done by
Herodoiui' celebrated Lake Moiris. At one lime there was
a hope that such a storage basin might be found. An
American gentleman, named Mr. Cope Whitehouse, in search
of the real .Micri^, f.iund a very remarkable saucer-shaped de
pression just south of the Fayiim. We knew it coul-t not have
been NKeri.s, because in its bed we found no traces of a deposit
of Nilotic mud, but it might be possible all the same to utilise
it. The place was very carefully surveyed, and the project was
estimated ; but it was found that the co-t of conveying the water
into this basin would be so great that it was out of the question.

Attemion was then turned to the possible sites where a stone I
dam might be built right across the river. The souihern i
bounitary of Egypt just now is near Wady Haifa, the second
cataract. It is no use going to look for sites south nf this, for
the country is in the hands of the M.ihdi and his fierce dervish
soldiers. North of this point, unquestionably the best site,
perhaps the only possible site is where the Nile valley is i
traversed by a broad dyke of hard Syenite granite, in passing
over which the river forms its first cataract just south of Assouan.
It is here divided into several channels between rocky islands,
and no channel is deep, so that it would be easy to divert the
water from one after another, to lay bare the bed of the river,
and lay the foundations of the dam in the open air. It wants
no engineer to understand what an adv.intage this is.

And the great dam, Mich as was <le«igned by Mr. Willcocks,
would have been a work worthy of the land of the Pyr.imiil-and
Karnak — a great wall of squared granite blocks — 82 feet thick at
base, of a maximum height of 115 feet, ij miles 1 mg, pierced
by sluices large enough to allow of the whole Nile at highest
flood rushing through. The lake formed would have been 120
miles long. Would this not have been a work of some majesty
to commemorate for ever the English rule in Egypt — a work
one would have been proud to have had a hand in ? But it was
not to be. The Egyptian saw no objection to it. The money
could have been found. But there was an insuperable obstacU
created when, on the Island of Phil.-e, about 250 D.c, Ptolemy
II. built a temple to Isis, on the site of older buildings long
disappeared. Round this temple other buildings clustered,
built by Greeks and Romans. Those of you who liave not seen
them, are probably familiar from pictures with the group of
venerable buildings standing amidst palm trees on the rocky
island, and reflected in the waters below.

Had Ptolemy only built his temple on the island of Elephan-
tine, a few miles north, it would have been unaffected by the
great dam, but Philae is just to the south, or up-stream side
of where the great d.im must necessarily have come, and in
consequence the island, with its temples, would be drowned for
about SIX months every year. Vou probably remember the out-
burst of rage and indignation which the announcement of this
proposed desecration created in London last summer. It was
not to be tolerated that England should commit such
vandalism. In vain it was answered that the place belonged 10
Egypt, not to Engl.ind— that the Egyptian, who was to gain so
much by the dam, cared absolutely nothing aliout Ptolemy and
his temples — that he was prepared to pay a large price for a
great work to benefit his country. What business was it of
England to forbid him ?

.\nd it w.as not only the English who were indignant.
For oiice, and only for once, I fear, since we occupied
Egypt in 1882. was educated opinion in England and Kranceat
one. Both alike insisted that Philae should not he drowned.
Nor must I admit had all the engineers that wereinlereslcd in the
question the full courage of their opinions. While they longed
to build the dam, and lamented the perverse fate that h.id put
Phili- there, still they wished to spare Philae — and their voice
has prevailed. The majestic structure has been cut down 27
feet, nnd now will only be 88 feet high, and Phil.%- will stand
henceforth in a lake, but will never be drowned.

Personally I accrpt the situation, (or I never believed that it
would be sacrificed. But yet as an engineer, I must sigh over the
lost oppiri unity for ICngljnd of making such a splendid rcservnir.
And «s a friend to Egypi, I nigh still more that thccounliy will
not have such a splendid supply of water as wouM enable
Upper Egypt to have the full lienefiis now possessed by Lower
Kgypli '"id Lower Egypt to expand and flourish.

NO. 1323. VOL. 51]

The reduced scheme will, however, be a great boon to the
country, nnd I trust will now be put in hand without delay.

In 1S84, when the expedition up the Nile was first being
considered, I was asked by the General Otlicer command-
ing in Egypt, whether I thought there was any possibility
of the Mahdi diverting the river in the Soudan, and depriving
Egypt of its water. The late Sir Samuel lijker was in Cairo
at the time, and I consulted him as to whether he knew of any
place in the Nile valley where during hiL'hest flood the water
spills off to the right or lefi, towards the Red .Sea or the
Libyan Desert. He said he was sure there was no such place,
and I then told the General it would be impossible for the
Mahdi to divert the Nile. I was sure that with his sav.iges he
would never dam up the low supply until its surface attained
the height of flood supply, and if even then during flood there
was no spill channel, Egypt was safe enough.

But what the Mahdi could not do, a civilised people could do.
A Government official has no business to talk politics, and the
Royal Institution is no place for politics; but I may be allowed
to point out an evident enough fact, that the civilised possessor
of the Upper Nile valley holds Egypt in his grasp.

At this moment the Italians are on the eastern edge of that
valley — a nation, I must say, who have been consistently most
friendly to us in Egypt. Supposinj^ ihat they occupied
Khartoum, the first thing they would naturally and very properly
do would be to spread ihc waters of the Low Nile over the
Soudan: and no nation in Europe understands irrigation so
well. And what then would become of Egypt's cotton crops?
They could only be secured by a series of the most costly dams
over the river, and the fate of Philae would surely be sealed.
But more than this : a civilised nation on the Upper Nile
wouM surely build regula'ing sluices across the outlet of the
Victoria Nyanza, and control that great sea as Manchester
controls Thirlcmere. This would probably be an easy opera-
tion. Once done, the Nile supply would be in their hands;
and if poor little Egvpt had the bad luck to be at war with
this people on the upper waters, they might flood them, or
cut off their water supply at ilicir pleasure.

Is it not evident, then, that the Nile from ihe Victoria Nyanza
to the Mediierranem should be under one rule ? That time
is perhaps far olT. I conclude what I have to say to-
night, by giving you the assurance, and I challenge contra-
diciion, that at no time in the long history of Egypt under
Pharaoh or Ptolemy, Roman or Arab, or Turk, have the
people of the country been so prosperous, or so justly ruled
as during the last nine years.

OBSER VA TIONS OF S UN-SPO T SPEC TRA . '

I. The Widening of Iron Lines and of Unknown Lines in
Relation to the ^unspot Period.

TT is now twenty eight years since I discovered that the lines
seen in sun-spots were subject to widening,- and that dif-
ferent lines were widened at different times.

It was not, however, till 1S79 that I was enabled to com-
mence daily routine work of such a nature that all observations
were comparable i«Av se. This desideratum was secured by
limiting attention to the twelve lines most widened between K
and D.

In 1886 ' I gave an account of some of the early results ob-
tained by this research. I have recently commenced the com-
plete discussion of the whole series of observations to the
present year.

This discussion, involving 21,000 lines widened during the
period in question, has necessitated three special researches:
the first, dealing with the lines with which, contemporaneously,
coincidences have been found in ihe laboratory ; ihe .second,
dealing with those the origin of which is so far unknown : aiid
the third, with the distribution of both sets of lines in spots ii^
relation to the sun-spot period.

To make the woik as definite .as possible, I am, in the first
instance, confining the inquiry concerning the known lines to
lines ol iron b.rsed u|)on the examination of the pure electrolytic
iron referred to in a previous communication.

' A Paper read ai llie Royal Society, by J. Norman Lotkycr, C. U.,
F.R.S.
- ■' Roy. Soc. Proc."vol. xv. p. 956, 1866.
3 " Roy. S'ic. I'roc." vol. xl.p. 347.
* ■' kuy. Soc. Proc." vol. liv. p. 35^.

March 7, 1895]

NATURE

449

The following statistics will show the relation of these iron '
lines to the Fraunhofer lines In the region F — D over which
the spot work extends. In the table, " terrestrial lines" means
lines which have been photographically recorded by myself or
my assistants in the spectrum of some metal or another during
the past tweniy-fnur years ; " unknown " means a line not so
far traced by me in any metal with the exception of Cerium.
This exception is necessitated by the fact that the spectrum of
that metal contains practically as many lines as appear in the
solar spectrum. The wave length map of Rowland's second
scries has been taken as a standard.

, 1880
/1200

82

84

86

88

90

92

94

96

NUtVIBER

TIMES

WIDENED I

UNKNOWN LINES

^

y

^

r-

-/

/

\

V

/

/

V

S

/ 1

/

^

i

t

/

"~~~-^/'^ fsPOT

1 '

2 '

3'

4 '

p'6

'7'

8

'

1 ! '° ! "

hundred;

1 i 1

IRON l-INES

\

■

\

^

\ !

\

,

^

^

\ i-

\

X

■^

\

N

1

/

/

'

V

— 1

^—

i

8U^

-SF

OTi

(S

'OB

ER)

/

N

r^

r

k

r^

/^

V

\

^

f^

l^

>

^

\

">c

^

1

1 1

sur

l-\3POTS (SPORER)

•-•

v

^

N^

■^

-*>,

1
1

^

'^

v^

^^

V

■^

;

^

V,

^

1

1 1

1

In the present communication I confine myself to submitting
provisional curves based upon a preliminary inquiry into the
number of times the lines of both categories have been
observed to be widened in spots. S'>me slight correc'ions will,
doulitless, he ultimately required when a few uncertainties con-
nected with some of the earlier observations, made before Row-
land's maps were available, have been cleared up. The
highest points of the curves represent the maximum frequency
of iron lines in one case and of unknown lines in the other.

The period embraced by the observations practically enables
us to study what has taken place at two successive sun-spot
minima and two maxima. It will be
seen that the phenomena which followed
the minimum of 1S79 have been
exactly reproduced after the minimum
of 1S90. At the minima the iron
lines are prominent among the most
widened lines ; at the maxima we only
find lines about which nothing is
known. Since the discussion indicates
that the iron lines involved, which ulti-
mately disappear, ate almost invari-
ably those seen most prominent in the
spark, the view put forward in my paper
of 1886 that the change observed is
due to the dissociation of iron in the
spots as a sun-spot maximum is ap-
proached, is corroborated, and, so far,
I have heard of no other simple and
sufficient explanation.

It will be noted that the maxima
and minima of solar temperature thus
revealed to us, If my hypothesis be con-
firmed, lag behind the spot maxima
and minima. This may explain the
lag observed in those meteorological
conditions, the secular changes in
which have been held by Balfour
Stewart, Broun, Meldrum, Blanford,
Chambers, and others, to prove that
the distuibances and changes in our
own atmosphere are affected by those
taking place in the atmosphere of
the sun.

1800 82

84

86

88

90

92

94

96

Region.

Fraunhofer

Terrestrial

Unknown

Iron

lines.

hncp.

lines.

lines.

F

4861 — 4900...

92

41

5'

lO

4900—5000...

■75

96

79

45

5000—5100...

228

92

136

33

5100—5200..

176

92

84

39

5200—5300...

.65

83

82

32

5300—5400...

211

76

'35

29

5400—5500...

216

63

>S3

26

5500—5600...

186

57

129

3"

56CO— 5700 ..

140

73

76

29

5700— 58CO..

198

48

150

22

5800-5895...

208

3"

177

3

D

2004

752

1252

307

VARIATION IN ANIMALS
AND PLANTS.'

'T'lIE importance of variation as a
factor in organic evolution is not
seriously dispuied ; but, if one may
judge from the expres-ions ci,n'amed
in recent essays, naturalists aie not
agreed as to the manner in which
variation among individuals is asso-
ciated wiih specific modification.

The view originally put forward
by Darwin and Wallace is that
specific modilication is at least
generally a gradual process, result-
ing from "the accumulation of innumerable slight varia-
tions, each good for the original possessor" ("Origin cf
Species," chap. xv.). This view rests on the assumpiion that
each of those small differences which are to be observed among
a g'oup of individuals belonging to the same species has
generally some effect upon the chance of life. " Can we doubt
(remembering that many more Individuals are born than can
possibly survive) that individuals having any advantage, how-
ever slight, over others, would have tlie lest chance of sur-
viving and of procreating their kind?" ("Origin of Species,"
chap. iv. ).

Of late years, another view has received support from various
writers. An examination of any series of animals of the same
species preserved in a museum sliows in most cases a large
majority of specimens which are superficially alike : those
individual diftercnces, upon which stress is laid by Darwin and
by Wallace, are often so slight as to escape attention tjnless
minute comparison is made between individual and individual.

■ A paper read at the Royal Society on Fcl>ru.-iry aS, by Piof. W. V. R.
Weldon, F.R.S.

NO. 1323, VOL. 51]

450

NA TURE

[March 7, 1^95

But there will commonly be fouad a few individuals which differ
so remirkably from their fellows as to catch the eye at once.
Such large deviations differ (rom the smaller ones, at least in
mc-t casts, by their extreme rarity ; but they have been ex-
tensively collecied, and most museums contain numerous
examples of il\eir occurrence. Some naluralis's have been led,
from the striking characier of such variations, to assume for
them a preponderant share in the modification of specific
character. These persons assume, if I understand them rightly,
that the advantages or disadvantages which accompany the more
frequent slight abnormalities are in themselves of necessity
slight ; and that the elTect of such slight abnormalities may be
neglected, in comparison with the effect produced by the
occasional appeatanceofconsiderable deviations from (he normal
type. They regard change in specific character as an event
which occurs, not slowly and continuously, but occasionally and
by steps of considerable magnitude; as a conseciuence of tlie
capricious appearance of "sports."

Without presuming to deny the possible effect of occasional
" sports " in exceptional cases, it is the object of the present
remarks to discuss the effects of small variations, as it may be
deduced from the study of two organs in a single species

The case chosen is the varia'ion, during growth and in adult
life, of two dimensions of female Carcinus nutnas, recently
investigated by a Commitiee of the Royal Society ; and what is
here said may be considered an appendi.v; to the report of that
Committee.

The questions raised by the Darwinian hypothesis are
purely statistical, and the statistical method is the only one at
pre.'>ent obvious by which that hypothesis can be experimenially
checked.

In order to estimate the effect of small variations upon the
chance of survival, in a given species, it is necessary to measure
first, the percentage of young animals exhibiting this variation ;
secondly, the percentage of adults in which it is present. If ihe
percentage of adulls exhibiting Ihe variation is less than the per-
centage of young, then a certain percentage of young animals has
either lost the character during growth or has been destroyed.
The law of growth having been ascertained, the rate of destruc-
tion may be measured ; and in this way an estimate of the
advantage or disadvantage of a variation may be obtained. In
order to estimate the effect of deviations of one organ upon the
rest of the body, it is necessary to measure the average
character of the rest of the body in individuals with varjing
magnitude of the given organ ; and by the application of Mr.
Gallon's method of measuring correlation, a simple estimate of
this effect may be obtained. In the same way a measure of the
effect of parental abnormality upon abnormality of offspring may
be numerically measured by the use of Gallon's correlation
function, and such measurements have been made, in the case of
human stature, by Mr. Gallon himself.

It is to be observed that numerical data, of the kind here
indicated, contain all the information necessary for a knowledge
of the direction and rate of evolution. Knowing that a given
deviation from the mean characier is associated with a greater
or less percentage death-rale in the animals possessing it, the
importance of such a deviation can be estimated wiibout the
necessity of inquiring how that increase or decrease in the
death-rate is Iruught about, so ibat all ideas of "functional
adaptation " become unnecessary. In the same way, a theory
of the mechanism of heredity is not necessary in order to measure
the abnormality of offspring associated with a given parental
abnormality. The importance of such numerical statements, by
which the current theories of adaptation, iScc, m.ay be tested, is
»trongly urged.

The report itself describes an attempt lo furnish some
of the numcric'l data referred to for two dimensions of the
shore crab. The data collected give an approximation to the
law of frequency with which deviations from the aver.ige
character occur at various ages. The conclusions drawn ate
(rt) Iha' there i» a period of growth during whrch the frequency
of deviations increases, illu-.traiing Darwin's statement that
variations frequently appear late in life ; (h) that in one case
the preliminary increase is fidlowcil by a decrease in the fre-
quency cf deviations of given magnitude, in the other case it is
not ; and that (n, awuming a particular law of growth (which
remains, at it admitted, lo be experimentally tolcd), the ob-
served phenomena imply a selective destruction in the one case,
and not in the other.

It is not conicnded that the law of frequency at various ages.

adoplcd in the report, is exact. It is, however, hope! that the
approximation is suiliciently exact to give numerical estimates
of the quantises measured, which are at least of the same order
as the quantities themselves, and for this reason it is hoped
that the njethod adopted may prove useful in other cases.

SCIENCE IN THE MAGAZINES.

TX the I'ebruary number of the K^rlnighlly, Dr. A. R.
Wallace discussed in some detail Mr. Hateson's views on
variation in relation to the method of organic evolution. He
concludes hisaitack in the current number, and considers Mr.
Francis Galton's views, stated in " Natural Inheritance " and
in "Thumb an<l Finger Marks." It is held that the methods
of organic evolution favoured by Mr. Bateson and Mr. Galton
have failed to establish themselves as having any relation to the
actual facts of nature. The reason for their failure is stated by
Dr. Wallace as follows : — "they have devoted themselves too
exclusively to one set of factors, while overl loking others which
are boih more general and more fundamental. These are — the
enormously rapid multiplication of all organisms during more
favourable periods, and the consequent weeding out of all but
the fittest in what must be on the whole stationary populations.
And, acting in combination with this a;;/;;/.!/ destruction oftlia
less tit, is the/.viW;Va/ elimination under recurrent unfavour-
able conditions, of such a large proportion of each species as to
leave only a small traction — the very elect of the elect — to con-
tinue the race. It is only by keeping the tremendous severity
of this inevitable and never-ceasing process of selection always
present to our minds, and applying it in detail to each suggested
new factor in the process of evolution, that we shall be able
to determine what part such factors can take in the production
of new species. It is because they have not done this, that the
two authors, whose works have been here examined, have so
completely failed to make any real advance towards a more
complete solution of the problem of the Origin of Species than
has been reached by Darwin and his successors."

A story worth repeating here is told by Mr. John Murray,
the publisher, in Gooii lV,'>ds. One day Charles Darwin came
to see the late Mr. .Murray, and brought with him a MS. As
he laid it on the table, he said, " Mr. Murray, here isa book
which has cost me many years of hard labour ; the preparation
of it has alVorded me the greatest interest, but I can hardly hope
that it will prove of any interest lo the general public. Will
you bring it out for me, as you have done my other books ?
The booli was Darwin's famous work on " Karthworms," which
in the course of three months reached a fifth edition. Mr.
Murray gives the incident as an illustration of the extreme
modesty of a very distinguished man. The same magazine con-
tains some stories of snake cannibalism, by Mr. H. Stewart.
A very readable story, in which observations of the planet Mars,
and projects of signalling to our ruddy brother, arc described,
is contributed by Sir. J. Munro to Cassell's Fiimily Magiizii:-
Mr. .Munro makes the Martians signal to us by means of ligl '
from various incandescent elements, the natures of which aie
detected spectroscopically. lie has a lively imatjination, and
is fairly accurate in his astronomical references In the English
llltistraleil, we notice another of Mr. Grant .Mien's " Moorland
Idylls "^ihis time on butterflies; and also something about lions,
by Mr. I'hil Robinson. In \.\Mi Strand Magazint, Mr. J. Holt
Schooling gives a number of ingenious diagrams for graphically
representing statistics relating lo the population of different
countries. I'hcre is also the concluding pait of an article by
Mr. W. G. FiizGerald, on " Some Curiosities of Modern Photo-
graphy," in which, among other illustrations, occur I'rof. Boys'
pictures of moving bullets, and a good reproduction of Dr.
Koberls' photograph of the nebula in Andromeda. Another
article of interest to photogra|)hcrs appears in Lc Mondt
Moderne (or Vehraaiy, under the title " Lcs Mouvcmcnts de
I'Ouvricr." A number of excellent reproductions of some of
M. Marey's photogiaphs accompany this article. The same
magazine contains a description of compressed air systems of
tramway traction.

In addition to the mag.azines menlioncd in the foregoing, the
following have been received, but they do not contain any
articles of scientific interest : — Conlniiporary, Century, Scrihner,
Chaml'trs\ , Longman's, National, Sunday Magaiine, and
Humanitarian.

NO. 1323, VOL. 51]

March 7, 1895]

NA TURE

451

UNIVERSITY AND EDUCATIONAL
INTELLIGENCE.

OxroRD. — An examination will be held at Merton College
on Tuesday, July z, 1S95, and following days, beginning at
10 a.m., for the purpose of electing to three open Natural
Science Scholarships, of which one will be at Meiton College,
one at New College, and one at Corpus Christi College.

The scholarships are of the value of ;^So per annum, and are
open to all candidates whose age on July 8, 1895, will not ex-
ceed nineteen years. The subjects of examination will be (l)
Chemistry, Mechanics and Physics, or (2) Biology. An English
I essay, and a paper in Algebra and Elementary Geometry, will
also be set to all candidates. Candidates will have an oppor-
tunity of showing a knowledge of higher m.i hematics. Can-
didates who offer Biology are requested to send to the Tutor in
Natural .Science, Merton College, at least one fortnight before
the examination, a general statement as to the portions of the
subject which they have studied, and the practical work which
they have done. All such candidates will be required to show
■ iiiiie acquaintance with Chemistry, .Mechanics and Physics.

('AMiiRii)GE. — The following is the speech delivered on
Ki.bruary 28ih by the Public Orator, Dr. Sandys, Fellow and
i'utor of St. John's, in presenting for the honorary degree of
Doctor in Science .Sir William MacGregor, M.D. (.\berdeen),
K.C.M.G., Administrator of British New Guinea : —

Orbis terrarum inter insulas, praeler Australian! latissime
p.itet insula Australiae parti septentrionali ex adverso po'iiia.
Tota quidem insula insulis Briiannicis dupio ma'or : insulae
autem pars a liritannis occupata Anglia ipsa maior aimidio.
Nostrae vero coloniae ibi administrandae praeposi'us est vir
insignis, olim in Academia Abeidon'ensi ir edicinae doctor, nuper
scientiarum complurium non modo fautor et adiutor, sed etiam
ipse auctor atque investigator indelessus. Praesidis nostri
auxilio, Anthropologije, Geographiae, Geologiae, aliis denique
^cientiis nova lux affulsit, adeo ut coloniam illam remotissimam
non tarn imperii nostri propugnaculum quam scientiarum arcem
ft castellum longinquum appellaverim. De Caledoniae fiiiis,
quibus uhique terrarum plurimum debet Britannia, nonnum-
quam dicitur, cum peregre absint, turn demum sese seniire esse
'l')mi. Iluic Caledoniae filio paullisper reduci gratias hodie id-
ciico a'^imus, quod, a patiia vocatus, non modo imperii nostri
in utilitatem, sed etiam scientiae ad fructum, palriam relinquere
est dignatus. Gens autem ilia antiqua, ex qua ortus esse
dnlitetur, olim sedibus paternis expulsa et ipso nomine prorsus
[uivata, hodie, talium virorum auxilio, non sine nomine, non
sine gloria est. Etenim gens ilia Alpina, gentem fortissimam
a poel;i Romano quondam laudatam aemulata,

duris ut ilex tons.i bipennibus,
nigrae feraci frondis in Algido,
per damna, per caedes, ab ipso
ducit opes animumque fcrro.

Duco ad vos equitem insignem, Willel.mu.m M-\cGregor.

The Report of the Syndicate for the encouragement of advanced
study and research has just been issued. It proposes that
approved graduates of other universities, of not less than twenty-
one years of age, should be admitted as Advanced Students,
with certain special privileges. Such students ate to pursue,
under the supervision of committees of the special Boards of
Studies, (a) courses of advanced study, or {b) courses of research.
The former chus may be admitted, after three terms, to a part
of a Tripos examination, and if they attain therein a sufficiently
high standard, their names will appear in a special list distinct
from the Tripos list. After residmg two years, tliey may be
admitted to the B..\. degree, and thereafter proceed in the
usual course to the M..\. and other higher degrees. Research
students are, after three or more terms' residence, to present a
dissertation adjudged by a Degree Committee to be **of dis-
tinction as an original cintnhution to learning, or as a record
of original research." Kor this a special "Certificate of Re-
search " is to be granted by the University. Holders of the
certificate who have resided at least two years, are to be entitled
to the B. .A. degree, and to proceed to higher degrees in the
ordinary course. Cambridge graduates may, on like terins,
obtain the "Certificate of Research." The original proposal to
establish new degrees (B. Lilt, and B.Sc.) for the class of
advanced students, has been dropped ; but the possil)ility of
proceeding to the higher degrees of the University is a new
feature of importance. The Report is signed by all the twelve
members of the Syndicate, including the Vice-Chancellor and

NO. I-?2^, VOL. 51]

eight professors, representing both the literary and the scientific
departments of University study. It will come before the
Senate for public discussion during the present term. The
main lines of the scheme resemble those of the plan provision-
ally adopted at Oxiord, with the important difference that
Oxford has taken up the idea, discarded at Cambridge, of
founding special literary and scientific degree; for post-graduate
students, and does not propose that they shall be eligible for
the degree of M.aster of Arts.

A University Lectureship in Pure Mathematics will be vacant
at the end of the present term, by the resignation of Dr. For-
syth, elected Sadlerian Professor. The lecturer will hold office
for five years from Midsummer, 1895. Applications are to be
sent to the Vice-Chancellor before Wednesday, -April 24, 1895.

An examination for diplomas in .Vgricultural Science will be
held in Cambridge in the week beginning [uly i, 1895. The
names of candidates are to be sent to the Registrary by
June 12.

One or two of the new provisions in the Revised Code for
Elementary Day Schools, presented to the House of Commons
last week, are worth noting here. Kindergarten methods of
instruction have been recognised in in.'ants' schools for some
time, but they have usually ended in the infant school.
" Object-lessons and suitable occupations" are now, however,
to be counted as class subjects in the lower standards of elemen-
tary schools, so that the lessons which are so valuable in
training the intelligence of the infant children will be extended.
Properly carried out, these natural methods of instruction are
of extreme importance in developing such powers of obser-
vation and reasoning as young children possess. .Another
commendable addition which Mr. Acland has introduced into
the Code permits visits to be made, during school hours, to
museums and art galleries ; not more than twenty hours in the
school year to be thus employed. Visits to the museums at
South Kensington cannot but have a beneficial influence upon
the minds of children, and if the guide is competent, they may
be made of great value. Perhaps the new feature will lead to
the establishment of science museums in towns where none at
present exist. It may also assist in the reduction of the bric-a-
brac element (which makes many small museums little more
than variety shows), and improve the arrangement and character
of the collections.

SCIENTIFIC SERIALS.

American Meteorological yoiirna!, February. —The cause of
the cyclones of the temperate latitudes, by W. H. Dines. Two
theories have found considerable support : (l) the convectional
theory, commonly known as Ferrel's, because he so fully ex-
plained it, and showed that cyclones were caused by the con-
vectional ascent of a current of warm air in the central parts,
the heat necessary to sustain the current being supplied, at
least in part, by the latent heat set free by the condensation of
aqueous vapour ; (2) the theory proposed by Dr. Hann, who
considers that the storms are merely eddies formed in the
general easterly drift of the atmosphere in temperate latitudes,
just as small whirls are formed in a river. Dr. Hann found
that the temperature at high mountain stations in the Alps is
higher during aniicyclonic conditions than during the passage
of storms. Mr. Dines thinks that the evidence is in favour of
Ferrel's theory, as mathematical laws show that it is a possible
one, and that the latent heat set (ree by the condensation of
moisture will, if it take the form of kinetic energy, be
sufficient to produce a most violent storm. — Recent foreign
studies of thunderstorms : Russia, by R. De C. Ward. The
Imperial Geographical Society of Russia instituted a special
study of thunderstorms in 1871, which has been continued until
the present time. This service, and others subsequently
established, such as that in south-west Ruisia by Prof.
Klossovsky, have led to some valuable results. The district of
greatest thunderstorm activity is the Caucasus, then the
southern central region. The predominant direction of move-
ment is north-east, and the storms occur most frequently in
June and July, the maximum frequency being in the afternoon.
— The y.<K;-«i:/also contains other articles of minor importance,
including one on the moon and rainf.ill, by Prof. H. .-X.
Hazen. The figures for Boston show a remarkable maximum
at the day of new moon, and an equally remarkable minimum
two days after full moon.

45^

NATURE

[March 7, 1S95

foumal of the Russian Ch/mical and Physical Soiiely, vol.
xxvi. pirts 2 to 8. — Among many valuable papere in-erted
in these issues, the following are especially worthy of
notice: — On the speed of formalim of the amines, by N.
Menschuikin — On the nitration of saturated hydrocarbons
by means of nitric acid, by M. Konovaloff. — On the solubility
of anhydrous calcium sulphate, by A. Potilitsin:;. — • >n the
isomcrisaiion of aromatic hydroearbons obtained by Friiel's
method, by M. Konovaloff. — On the structure of terpenes and
similar compounds, by G. Wagner. — On the nitration of un-
saturated hydrocarbons, by means of nitric acid, by M.
Konovaloff. — On the halogen compounds of nitrogen, by Th.
Selivanoff. — In the physical part : On the electric resistance
of bis-nuth to altemati'.f currents, by A .Sadovsky. — On the
valuation of electrostatic energy, by M. Schiller. — On the
variation in length of iron wire during magnetisation, by M.
Rosing. — Experiments with alteroatmg currents of high fie-
quenc>, by N. Slouginoff.

Part 2 of the Journal contains also, as a supplement, the
first number of the Memoirs ( I'nmennik) of the Central Board
of Measures and Weights, which was instituted in 1893, and is
]>Iaced under Prof. Mcndcleeff, who is also the editor of this
]>ublication. In this first part w; nd besi es a prelace by the
editor, several papers of more than local interest, namely :— The
measurements made to compare the iron sajine of the " Com-
mittee of the year 1833" with various units of length, ac-
complished in 18S4, by MM. Glukhoff and Zaw.idski. The
cjmparison was also made with tlie bronze and iron yards of
Airy. — On the weight of a litre of air, a very elab .rate paper
by Prof. Mendek'eff, in which some remarks conce n ng the
measarements of I.educ and Lord Rayleigh, and the corrections
which should be introduc;diiito their nieasireaicnls.arrespecially
valuable. Tlie average value arrived at by Prof. Mcndeldeff
is, in grams,

o = 0'l3l844..j- ± O'oooio.

— First list of the standard measures nf weight anl length at
the Central Board, by Th. Zawalski. — Data fir the elaboration
of an instruction for verifying the weights and measires in the
trade estahlisnments. — Prelimina-y researches into ne* scales
for grain, as a means of d:terminiag the quality of the latter,
by Th. Selivanoff.

SOCIETIES AND ACADEMIES.
London

Royal Society, February 7.—" On the Application of the
Kinetic Theory to Dense Gaies." By S. H, Barbury, F.R.S.

February 14 — "An Instrument for Cultinj, Grinding, and
Polishing Srction plates and Prisms of Mineralor oilier Crystals
.iccuralely in the dcjircd direction." By A. V.. Tution, De-
monstrator of Chemistry at the Royal College of .Science,
South Ken-ington.

In a recent comminicition [P!ii!. Tram. 1894. Series A.
p. 887) the aiilior described an instrument for grinding accu-
rately orient.t ed seciionpla'cs and prisms of crystals of arti-
ficial preparations. 1 he success of that instrument is so com-
plete that an'ilher instrument ha> dcen devised and constructed,
which enables equ.illy accurately oiienlaied plates or prisms to be
prepared from the relatively harder crystals of natural minerals.
The instrument is not intended to replace the one previously
deiciibed, which is fully adapted for all the purposes of
chemical cryslallographer=, and the cost ol which is only two-
thirds that o( the one now describeu. It is in'ended especially
for the use of mineralogists, but, naturally, will serve all ihe
|iurpoi;$ of the smaller instrument. It is cons ructcd upon a
scale one-fifth larger ihan the former one as regards such parts
as are fundarnenlally similar, to confer greater strength. The
mode of supporting the outer fiied cone within which the
inova'il; axes rotate, the consliuciion of the circle and its axis
and fine adjusimeni, and of the gun-mcial axis and its counter-
joitlng hvcrs designed for controlling the pressure between
cryital and lap, as als ) of the i iner steel axis from which are
suspended the crystal and its centering and adjusting move-
ments, aie similar in principle to the torrcspondin^ arrange
inenti in the smaller instrument, al>hough many details are
.Tltered for the sake of greaicr rigidity. The same likewise
applies tu the goniomclrical telescope and collimator and their

NO.

3123, VOL. 51]

mode o' support. The main innovations are those of a cutting
apparatus, ant a laigc grinding la' le capal'le of bring readily
furnished with any ore o( nine interchangeable grinding and
pibshing laps, suitable f>r use »i h cr\stals nf every drgree of
baldness. Four iietallic laps are jirovided, of iron, gun-metal,
hard white metal, and pewter respective ly, the first (or rough
g'i'ding with coar>e emery and I'nck oil or waier, the second
and th nl for fine grinding wiih (lour emery, and ihe fourih for
polishing with roticnsione and waier. A polishing lap of hard
fell, for use with putiy p iwdcr ar.d waier, an I a la|) of box-
wood, are supplied. Three glass laps, o le coar-ely ground,
another finely ground, and the third of ordinary polished plate
glass, arc likewise provided (or use wih ariifiL-ial cr)sals.
The culling apparaius is carried upon a hoiizont.il arm pivoted
about the back pillar ol the insirunient, in order to permi*. of
its removal out of the way during grinding and p 'iishing
operations, and further suppoitel when in use upon an adjunct
of the right Iront pillar. It consists o( a 4-inch disc of^ soft
iron, sup|ilied with diamond edge, and intended to be lubri-
ca'ed with brick oil, driven by an indejicndrnt driving gear
carried upon the arm. The supporting attachment to the fiont
pillar is removable "hen not required, and includes a travers-
ing apparatus lor directing and controlling the cutting, and a
safety back-spring to prevent the possilnbty o( undue pressure
being induced between the cu'iing di-c aid the crystal by
injudiciously rapid ro'ation 01 the traversing screw. In-tead
o( actuating the driving gear of the culling or grinding appa-
ratus by hand, a small electric, gas, or water mo'.or may be
empIo\ed.

"On the Ratio of the Specific Heats of some Compound
Gases." By Dr. J. W. Capstick, Fellow of Trinity College,
Cambridge.

The experiments described are a continuation of those
of which an account is given in the Phil. Train, vol. clxxxv.
p. I, Kundt's dust-figure method being used, and the ratio of
the specific heals correctrd (or deviation of the gas from lloyles
law. The results are as follows : —

Name.

Formula.

y

Methylene chloride

CHXIj
CHCI,

CCI4
CjH.Cls
C,H,C1,

C,H<

C.H,Br

C'jHjCl

C,H„Br

HCOOCjII,

CHjCOOClij

SHj

CO,

CS..

CCI^

1-219

'•'54
1130

1-137
'•'34
I •204

1-198

i'37
I 145
I 124

'••37
'■340
1-508

Carbon tetrachloride ...

E'hybne chloiide

ICthylideiie chloride

Vinyl bromide

Allyl chloride

Mt-thyl acetate

Sulphuretted hydrogen

Catbnn disulphide

Silicon tetrachloride ...

'■239
1-129

From these, and .the results given in the former paper, it
follows that

(1) Replacement of one halogen by another in a conpound

has no effect on 7.

(2) One H in a parallin molecule may in some cases (e.g.

ethane and propane) be replaced by CI without altering
7, but a second rcplacemeni always causes a (all.

(3) Carbon and silicon can be interchanged without effect on y.

(4) Isomeric compounds have the same y.

(5) Using 7 10 calculate 3, 1 he ratio of the rates of increase of ill'

traiiiolecular and Iranslational energy of the molecule OD

a rise of temperature, we find

fl-ti

is constant for the

parnllins and their monolialogcn derivatives, whence it
follows that for these the ratio o( the increase of mean
total energy to the inciense o( kinciic energy of trans-
lation of Ihe molecule is proportional to the number of
atoms in the molecule.
'- On some Considerations showing that Maxwell's Tlicorcm 1
of the I'.qual I'arlilion o( Fncigy among the Degiees ofj

March 7, 1895]

NA TURli

453

Ireedoti of Atoms is not inconsistent wiih the various In-
urnal Movements exhibiied by the Spectra of Gases." By
1 r.if. G. K. Fiizgeraltl, K.K.S.

U has been generally held that a sulTicient freedom of internal
motion in an aiom to explain the spectra of gases pioved that
the theorem as to equal partition of energy among all degrees
of freedom could not hold, and various siigg'Stions have lieen
made as to v\hy the proofs as given by Maxwell, IJolt/.mann,
anil others, fails in this caie. Prof Schuster has suggested that
the numerous lines need not involve the same number of
degrees of freedom, as it is possible that there maybe con-
nections between them such thai one or two coordinates would
define a mutton which when analysed into us Fouiitr com-
ponents, as is dune by a gratini; or prism, would proiluce a
very complex system of lines. II twever, even one degree of
internal deedom would inter fere very seriously with the observed
value of the ratio of specific heats, and the object of this note
is to ex| lain how this dilTiculiy may be surmounted without
supposing that the iheoiem as to tqual parttion of enerj^y is
untrue, f^r it is not by any means disproved because a certain
form of proof fails in certain cases.

It has been long held that the motion of the eleclrons on
neighbouring atoms is very much controlled by the ether
between them. The wave-lengih of light is geneially many
times as great as the molecular distances, so ihat the ethei is a
practically rigid connector beiween neighbouring electrons.
Suppo e now, as a particular example, that lO'' atoms are in this
sense, and so far as the motion of electrons is cc nctrnei', within
one another's control. In this case the motion of ihese ic''
electrons might be defined by means of, say, three coordinate^.
Hence, if the atoms were spheres, there would be 3 x 10** degrees
of freedom plus these three degrees defining ihe motions of all the
electrons. Now, if the total energy be equally distiibuted
among all these degrees of freedom, each atom will only have
its share of the electromolions, and its energy of external
motion will only be diminished by 3 x iO"*th part owing to the
existence of the internal motion of its electrons. I need hardly
say that our methods of calorimetry are by no means sufficiently
delicate to detect anything of this kin>l. There might be a
thousand such internal degrees of freedom, and yet the ratio of
specific heats wouldagree with observation.

The e is some analogy bt-tween this suggestion and the case
of a sphere moving in a liquid. The presence of the liquid,
although apparently endowed with an infinite numtier of degrees
of freed om, does not really increase the degrees of freedt^in at
all, because its motion is entirely defined by the motion of the
sphere. In a somewhat similar manner, I would suggest that
the presence 1 f the million electrons does not sensibly incrta'-e
the degrees of freedom of motion of the tuillion atoms, as all
their motions may be defined in terms of the motion of a few
of them. That the ether wouM so control ihe motit n-, of
electrons seems almost certain liom what we know of the
rapidity with which electromagnetic actions are transmitted by
it, showing how completely it behaves in respect of them as a
system of rigid connections.

"Note on the Disease of Cabbages and allied Plants
known as ' Finger and Toe,' &c." By George Massee, Royal
Gardens, Kew.

The disease known in different parts of Britain as "finger
and toe," "clubbing," or "anluny," attacks tumips, rape,
cabbages of all varieties, radishes, and, in fact, most culiivaicd
plants belonging to the order Cnicijerie. Several common
weeds are also attacked, namelv, charlock (Bra^siia iuia-
pistnini, Boiss.); garlic-muslatd (A.y'«;^/7«/« alliurii. Scop.) ;
Ireacle-muslaid (Ervshinim iluiranllwiJes, Linn.), and shep-
herd's puise (Ca/i6'/r'(! liiisa pasliins, D.C ). The last-named
is reported from the United Stales by Halsled (New Jersey
Agric. Coll. Expt. St;ition ; Bullelin 98, l!i93), and has not
been observed to be diseased in Britain, although one of our
commonest weeds. '1 he disease is characteriseil by the forma-
tion of numerous nrdules on the root, which becomes much
distorted and soon decays, forming a slimy, fctlid mass.

Bcikeley (Gani. Chron., ji. 5CO, 1856) a|ipears to have been
the first to invesiigate ihe disease from a scientific standpoint,
and alihough he did not succeed in deicimining the true c auc,
distinctly states that microscoi ic examination revealed the
presence of a factor previously unknown in cimnecrion wiih
plant diseases. Furthermore, Berkeley pointtd out that wood
ashes were a cure for the ilisease, and .supposed this to be due
to the presence of potash salts in the ash.

NO. 1323, VOL. 51]

Owing to ihe serious amount of dare age caused by " finger
ard toe" to the cabb?ge crtp in Russia, the Goveinment of
thst country olTered a tewaid lor the di'coverv of ihe cause of
the disease. Wort nin (" Pringsheim's Jahrt'," vol. xi. p. 54S,
tabs. xxix.-x>xiv., 1S7S) undeitnok the mvestigaiion, and alier
years of patient siudy published an elaborate cccount, proving
cleaily that the risease was caused by a minute organism re-
lated to the fungi, to which he gave the name Plasiiioiiiophnra
brassuiT.

In 1859, Voelcker (Roy. Agtic. Soc. Jctitii., vol. xx. p. loi,
1859) pointed out lhat the disease was inlluenced by the
am.untof lince present in the soil. Whi re little or no line
existed, as in light and sandy soils, the disease al ouniJed,
whereas in scil containing lime the disease was absent. This
opinion is corroborated by the same autlor at a later date
{Op. iil., series iii. vol. v. p. 321, 1S941.

A series of experiments have been carried out during four
successive years at Kew, and they demonslrate the following
points : —

(1) That in addition to cultivated plants, several common
weeds belonging to the oriier Crucifenc are attacked by the
PUnmoiiiophora. Hence the neces-ity for preventing the
growth o( such weeds in fields and hedge- bar ks.

(2) That the germs tf di.sease are present in soil that has
produced a diseased crop, and retain their vitality for at least
two years.

(3) That the development of Plasmodiophoia is favoured by
Ihe pre*ence of acids, and checked by the presence of alkalies,
agreeing in this respect »ith the furgi rather than wiih
bacteria.

(4) For the purpose of sterilising infected soil, experiments
piove that either a dressing of lime or a manure containing
pi tash salts is elTeclivp, the last heir g most valuable, as it not
only destroys the germs in the soil but also arrests the disease
in seedling plants, and at the same lime supplies one of the
ingreditnis necessary for the healthy growth of turnips.

February 21. — "Iron and Steel at Welding Temperatures."
By T. Wrights- .n.

The object of this paper was to demonstrate that the pheno-
menon ol welding in iron is identical wiih lhat of regelalion
in ii e.

The author recapitulated experiments made by him in 1879-
?o, described in the Proceedings of ihe Iron and Steel Institute
for those years. These experiments were upon cast iron,
and )rov(d that this form of iron possessed the properly of
expanding while passing from the liquid to the plastic stale
during a small ran^eol temperature, and then con racted to the
solid state, and thai the expaision amounted to about 6 per
cent, in volume. This property of iron resembles the-imilar
property of water in freezing, which, within a range of about
4' C., expands about g per cent, of its liquid volume, and then
contracts as the c<ioling proceeds.

This properly of waer was investigated by Prof. James
Thomson and by Lord Kelvin. The former showed that from
iheoreiical considi rati' ns there was reason to expeci that in the
case of a body exhibiting the anomalou-- properly of expanding
whin looled and contracting when heated, it shoulil be cooled
instead of heated by pressure or impact. Lord Kelvin in-
vestigated Ihe problem experimentally as affecting freezing
water, and completely demonstrated the truth of his brother's
reasoning.

The experiments made by the author in 1879 and 1S80
suggested the vie* that this property of ice was connected with
ihc pro| eriy of welding in ipin, bui his was only hy[io helical,
as ihe experiments had been made on rasi iron, wh ch piobably,
on acci uni of the presence of carbon, does not possess the
property of weldirg, Further, it was ni>t piaciicahle to experi-
ment with M roughi iron in the same way as with cast iron on ac-
count of the difficulty of dealing n iih lhat substance in its liquid
form. Prof, l-iolierts-Auste" has, however, given metallurgical
research a recording piirometer, anil ibis has enableil the author
to resume the invesiigaiion al the Mint, The method adopted
was ihe healing of bars in an eh ctrie wehler, and as sron as
the junction of the bars was at a weMing temperature, end
pre -sure was applied by mechancal power, anil the weld effected.

Olserval'ons show thai a molecular lowering of temj'crature
look place in meriiarely the pressure was appliid to the bar
when rn the welding condition

Tl e fall in iem| etatuie vrried'frrni 57° C. to 19° C, accord-
ing to the cireunistances of tempi raiute and pressure.

454

NA rURE

[March 7, 1895

The expeiimems appears to prove that wrought iron at a
welding temperature possesses the same property of cooling
under pressure which was proved by Lord Kelvin to exist in
freeiing water, and on which demonstration the generally
received theory of regelalion depends.

The author distinguishes the process of melting together of
me:als from that of welding. Either process forms a junction,
but the la'ter takes place at a temperature considerably below
the melting point.

The well-known and useful property of welding in iron
appears, therefore, to depend, as in the case of regelalion in
ice, upon this critical condition, which exists over a limited
range of temperature between the molten and the plastic state.
" Note on the Spectrum of Argon." By 11. F. Newall.
In the course of a spectroscopic investigation in which the
author has been for some lime past engaged, a line spectrum,
which 50 far as he was able to make out was unknown,
had frequently presented itself upon his photographs. It
appeared in May and June, 1894, under condition^ which led
him to call it, lor the sake of convenience, "the low-pressure
spectrum." It now appears that the lines are argon lines.

The argon o( which the spectrum was observed was obtained
from air, from which niirogen was eliminated by parsing electric
discharge through it in presence of hydrogen or moisture and
acid. Seventy two lines in the author's "low-pressure
spectrum" had their wave lengths given in the paper, and side
by side were given the measurements of the wave-lengths
determined by .Mr. Crookes for the argon lines.

The agreement of the measurements s hows conclusively that
the same spectrum was observed. The agreement of grouping
and intensity, also, leaves no doubt as to the identity of the two
spectrx

The experiments were repeated, with slight variations, several
times with results which, so far as the spectrum of argon is
concerned, were constant. But it was noted that c in inued
passage of the discharge appears to result in the attaining o( a
certain minimum pressure, after which there is slight and slow
rise to a toletably-fised pressure.

It is interesting to find argon asserting itself, unsolicited, in
quite new circumstances, and under conditions which practically
constitute one more mode of separating argon Irom niirogen —
namely, the getting lid of nitrogen by passing electric dis-
charge through it in the presence of hydrogen or moisture
and acid.

February 28.—" The Effect of Environment on the Develop-
ment of Echinoderm Laivae: an Experimental Inquiry into
the Causes of Vaiiation." By M. M. Vernon (from the
Zoological Station, Naples).

Tht: conditions of environment under which an organism
develops are known to be of considerable iulluence in the pro-
duction of variations. It was thought to he of interest to
determine by exact measurement the trfifects which such slight
change- in the environmental conditions as might occur
naturally would produce in ihegrowtn of some organisms. The
animal chosen was the larva or pluteus ol the sea-urchin
Strrni^yloctntrolus Itvidut. These larvje develop readily from
arlihcul leriilisations, and they can, moreover, be o named at
all lime? of ihe year, irrespective of season. In all 10,000
larvx were measured.

'1 he effects 01 temperature on development were first s'udied.
It was found that if the ova were pliced in wa era' about 8° or
25' C. for an hour, or even for a minute, at the time of im-
P'Cgnaiion, the resulting larva; after ti.;nt days development
Wire, on an average, 46 percent, smaller than those impregnated
at from 17° to 22', though all the su! sequent condiii.ms of
development wne identical. 11 kept at the almormal tem|icra-
lure for only ten seconds during impregnati .n, the resulting
larvx *crc only I 7 per cent, smaller.

The timcol the year when the artificial fertilisations are pre-
pared h.is a very marked inlliiencc on the size of the larvae.
1 hus, tho e ob ained in the middle ol August ate about 20 per
cei t. »m Her than ih.se nl>iaincd in April, May, and October,
whil t ihoic olita.ned in June and July arc interinciliate in
lize.

The iialinity of the water has also a great influence on the
developmrnl.

The effrciii which the variou* colours of the spectrum have
upon ihe iltvelopmcnt were al«) deietmined, ihoi'gh these are
Dot condition" ol envi.oimciil which occur In naure. The
development of the larva: seem* to be but little aflccled if it is

NO. 1323, VOL. 51I

carried out in absolute darkness, the size only being diminished
by I 3 percent. Larvae grown in semi darkness are apparently
25 percent, larger than the normal.

The body-length of the Inrva: appears to be uninfluenced by
the number of larvx developing together in a given volume of
water, if it be kept below 30,000 per litre. The arm-lenglhs
are, on the other hand, considerably affected.

Certain products of metaholism exert a favourable influence
on the developments of the larvje, and not, as would be
naturally expeced, a harmful one.

.\s the number ol measurements made was so large, it was
thought to be ol interest to subject them to statistical examin-
ation. It was found that with the body-length and oral arm-
length measurements the deviations from the average occurred
with a frequency indicated by the theoretical law of etior. The
measurements of the ahoral arm-length did not agree so well,
possibly owing to dimorphism.

Physical Society, February 22.— Captain Abney, F. R.S.,
President, in the chnir. — \n abstract of Mr. G. H. Bryan's
paper, on the mechanical analogue of theimal equilibrium
between bodies in con'act, was read by Mr. EMer. After com-
menting on the difficulty in applying the kinetic theory of gases
to the case of two substances in contact which do not mix, the
author goes on to describe a system by which the phenomena
of thermal equilibiium unaccompanied by diffusion can be ex-
plained. The two substances are represented by two sets of
molecules designated by 1' and Q. Two parallel planes A aiid
B, at a small disiance apart, are imagined to divide space in
three parts. Plane A ('o the left of B) is supposed to be
permeable to the P molecules, but to repel the Q molecules,
whilst B is permeable to the Q set of molecules, and repels the
P set. The spaces to the left ol A and to the right of B are
thus entirely occupied by the P and (1 molecules respectively.
Between the planes both P and (> molecules exist, and there-
fore have oppori unities of colliding with one another and
transferring energy from one gas to the other. Using
generalised dordinates, it is shown by Bolt^mann's method
that when equilibrium is attained the mean kinetic energies ol
translation of the two kinds of molecules are equal, just as ioi
the case of molecules which mix. Instead of assuming thtj
planes .\ and V, to repel the Q and P molecules respectively,
the P molecules may be assumed to be positively electiified, an<i
the (1 ones negatively electrified, whilst the planes A and I
are maintained at a constant difference of potential. Thi
difference of potential thus assumed is analogous to " contac
E.M.F." whose existence is proved by experiment. Thij
communication concludes with a development of Prof. Bolti j
mann'spaper on the application of the deierminanlal relatioi'
to the kinetic theory of polyatomic gases, read before thi:
British Association at Oxford. Dr. Stoney thought the argu
mcnts were based on actions depending on the distances of th'
molecules, an 1 the supposiiion that they were rigid. In hi

o|iini(m eve

nts occur in nature which are not represented b;'

his simple theory, and great reservation should be shown 11!
accepting dynamical pr .blems which leave out of accoun
actions occurring between matter and the ether. In natur:
nothing was large and nothing was small except relatively
Even molecules might possess infinite detail of structure
Their inter.action with the ether must be considereil in an,
complete theory. — Mr. G. U. Yule's paper on a new harmoni
analyser, and one by Mr. H. N. Allen, on the elect rom.igneti
ficlil, were postponed. .

Chemical Society, February 21.— Dr. Armstrong, Pres
dent, in the chair.— I'he following papers were read :— TbI
electromotive force of an iodine cell, by A. P. Laurie. Ih
E M.K. of a cell consisting of a zinc and pl.itinu o jilale ml
mcrscd in iodine dissolv.d in potassium iodi.lc solution is con
Slant, but is the smaller as the iodine solution is ihe moi|
dilut- ; Ihe.fTecl of varying the con-stituents of the cell on tlij
I' M V. has been investigated. —Ctmiribuiions to the chemlJli
otccilulose. by C. F. Cross, E.J. Hevan, and C. Beadle. TJ
meltii.gpoinis of mixtures, by II. Crompton an.l Miss M. /I
Whitcicy. When a solution deposits ihe pure solvent on coo

ing, the relation log s= ^f^^ . ^- ~ ^r h"''''* ! ' ^^ "-e numb.

ol molecules of solvent per molecule of solution, p is I'le njo'
cular latent heal of fusion of the solvent, and 1 tind 1 t
melting-poinis of ihe solv.nt and the solution rcspectively.--ll
volumetiic determination ol manganese, by J. Reddrop and I

March 7, i«95]

NATURE

455

Ramagc. Schneider's process for the delertnination of man-
ganese may he rendered much more accurate by substituting
sodium bismuihate for bismuth peroxide.— Bromocamphnric
acid, an oxidation product of ■jr-dibrcmocamphor, by F. S. Kip-
ping. .'V bromocami horic acid is obtained by oxidising ir-di-
bromocamphor ; its anhydride has been prepared together with
a new hydroxy-acid and a niirobromocamphnr. — Note on the
action of diastase on cold starch-paste, by H. T. Brown and G.
H. Morris. — On the magnetic rotation of some unsaturated
hydrocarbons, by W. H. Petkin. The magnetic rotations of a
number of unsatura'ed open chain hydrocarbons have been
determined ; a comparison of hexane, hexylene, dialiyi, and
dipropargyl shows that the differences bet«een ihe latter pair
are of a different order to those of the former pair.

Linnean Society, February 7.— Mr. C. B. Clarke, F.R.S.,
President, in the chair. — Mr. Thomas Chiisty exhibited a dried
specimen ot Aplopafpits Llaret,t and samples of the so-called
Gum Kino, Plerocarpiis eriiiaceiis, of which some account was
given by Mr. E. M. Holmes. Mr. George Murray exhibited a
number of lantern slides of floating Algu, of which he gave
brief descriptions referiing to the localities in which they had
been found and the literature relating to them. — By permission !
of the Director of the Royal Gardens, Kew, Mr. \V. B. Hem-
sley exhibited dried specimens of a number of new plants from
Eastern Asia. Conspicuous amongst these was a new genus of
Sci/nmine,,- from the mountains of Northern Siam, charac-
terised by having minute unisexual flowers destitute of stamin-
odia, a one-celled ovary with parietal placentation, and two
filiform stylodia ; a remarkably broad-leaved Lysiniachlcx from
the same region : new j-pecies of llypcriium, I'entilago,
Mesona, and Uelicia from !• ormosa ; and a new genus of Cyr-
tandrt:. From a collection made in Yunan, Western China,
by Mr. W. Hancock, of Hong Kong, came a new /asmimim,
allied to /. nudifloritm, with primrose yellow flowers an inch
and a half in diameter ; an elegant species of Petrocosmca
(Cyrlandreae), and a showy Braiiiiisia (Scrophularinese) with
long racemes of crimson flowers, which were much admired. —
Mr. Thomas Hanbury exhibited a beautiful collection of fresh
fruits of the Auitintii.;, grown in his own garden at La Mor-
tola, Mentone, and gave an account of some of the more
remarkable varieties, their mode of growth, and the conditions
under which they had been grown. — A paper was then read by
Mr. H. M. Bernard, on the comparative morphology of the
GaltoditL . Having described a possible origin for the Crustacea
from a ch^topod annelid by an adaptation of the anterior seg-
ments To a method of feeding, whereby the parapodia would
function as jaws, the author attempted the same for the Arach-
nida vith a view to solve the question of their relationship with
Merostomata. The Galeodid.,: were chosen for special study
. ^cause, unlike other arachnids, they have retained some seg-
ments of the cephalothorax as free movable segments, and
hence might he expected to throw light on the subject. The
author believed that he had solved the question of the primitive
specialisation of the arachnid phylum from their annelidan
ancestors, and expressed the opinion that as arthropods they
are not related either to the Crustacea (including Limuliis) nor
to the Hexapoda ; but that all these are distinct derivations of
the Annelida. In an interesting discussion which followed, the
paper was criticised at some length by Mr. A. U. Michael, Prof.
Howes, and Mr. R. I. Pocock.

Paris,

Academy of Sciences, February 25. — M. Lccwy in the
chair.^On the penetration of a projectile in .'emi-fluids and
solids, byM. H. Kesal. — On a class of tquations of which the
general integral is unifoim, by M. I'.miie Picatd. — On the
raeasuiement of time in astronomy by a method independent
of personal equation, by M. G. Lippmann. The author em-
ploys a photographic method. A platinum wire is rendered
incandescent for a very short time at the commencement of each
second by mechanical means. The light from the wire is, t^y
Ihe aid of arrangements described, thrown on to a photographic
plate in such a way that the image formed corresponds precisely
with the meridian of the place of observation. By suitable
exposure a phoirgtaph is obtained of a portion of the heavens
on the same jilate. The time of transit of a given star can
then be easily deduced from the horary circles photographed as
above. M. d'Abbadie remarked with reference to an altetna-
ive micrometric method proposed by M. Lippmann, that Bre-

guet had used a moving wire grating for measurement of the
same quantities fifty years previously. — On the mutual relations
of potential determinants, byM. de Jonquieres. — Ebullioscopic
study of certain colouring mauers from triphenylmethane, by
MM. A. Haller and P. Th. Muller. The conclusion is drawn
that, under the given experimental conditions, the hydro-
chlorides of the colouring substances of the triphenyl-
methane amido group are not dissociated, whereas the
chlorides of ammonium bases and nitrosodimethylaniline
hydrochloride are most clearly dissociated. Hence an
argument may be drawn in favour of formula of the
type of CIC ; (C,;Hj NH.)^ due to M. Rosenstiehl.
— M. Sappey gave a short description of the "Atlas of De-
scriptive Anatomy, " presented byM. Laskowski. — TheAcademy
elected ^L Weierstrass as foreign associate, the votes given
being: ^L Weierstrass 43, Prof. Frankland i. Prof. Huxley I.—
.\ closed communication from M. E. Carvallo, accepted May 2,
I S92, was opened. It gave the theory of the laws of crystalline
absorption. For uniaxial crystals these are: (it For the
ordinary ray, the index of refraction and the coefficient of ab-
sorption are constant, whatever may be the angle between the
luminous ray and the crystallographic axis. (2) The law of the
index of the extraordinary ray is not altered sensibly by absorp-
tion. (3) The absorption of the extraordinary ray is repre-
sented by the formula

'^'a = -jcos^e-h^.sin-e,

where /■, 11, © represent the coefficient of absorption, the index
of refraction, and the angle between the normal to the plane of
the wave and the crystallographic axis. \ memoir will shortly
be brought out dealing with these results and their develop-
ments.— M. L. L. de Koninck claims priority for the pro-
perties of nickel and cobalt sulphides. — Spectrum researches
on the rotation and movements of the planets, by M. H.
Deslandres. (See "Our Astronomical Column.")— Observa-
tions on the subject of the preceding communication by M.
Deslandres, by M. II. Poincate. The theoretical views which
have been confirmed by the foregoing results. — Determination of
the position of the pole by photography, by M. C. Flamniarion.
By exposure of a fixed plate, circular traces of the circumpolar
stars are obtained as shown in the figure given with the paper.
Hence the position of the pole can be obtained with great
accuracy. — On a surface of the sixth order which is connected
with Kummer's surface, by M. G. Humbert. — On functional
equations, by M. Lean. — On the exact invariants of an or-
dinary differential equation of the second order, by M. Tresse.
— On some theorems of Arilhiuology, by M. N. Bougaief. —
Lowerirg of the freezing point and relative diminution of
vapour pi essure in dilute solutions, by M. A. Ponsot. The
author deduces formulae differing somewhat from those given by
Wvillner and Raoult, and agreeing with those of van t'Hoffand
Duhem, with the exception that a different meaning is given to
one of the terms. — On the lowering of the freezing point of very
dilute solutions, by M. A. Leduc. The author proposes the
substitution of the measurement of a considerable pressure for
a small temperature difference. A theoretical demonstration. —
On a sensitive pressometer, for the measurement of fluid pres-
sures, by M. PaulCharpentier. — The measurement of the inten-
sity of light by the chemical action produced ; experiments with
mixtures of ferric chloride and oxalic acid, by M. Georges
Lemoine. — On some combinations of lead iodide with other
metallic or organic iodides, by M. A. Mosnier. A number of
new double salts have been obtained and their composition
determined. — On some combinations of nitric oxide with the
chlorides of iron, by M. V. Thomas. The substances:
(i) FeXl^.NO, (2) 2FeXIa.NO, (3) FeCl;.N0.2H20, and
(4) FtCLj.NO, have been obtained and their compo-ition
determined by analysis. — Action of formaldehyde on hy-
droxylamine hydrochloride and on methylamine hydrochloride,
by MM. A. Biochet and R. Cambier. — .\ctive amyl ethereal
salts, by MM. Ph. A. Guje and L. Chavanne. A paper
on the product of asymmetiy. — New researches on the corre-
lative variations of the intensitv of thermogenesis and respira-
tory changes, by M. Laulanie. — " .-tutonarcose carbonict-
acitoncmique," or winter sleep of the marmot, by M.
Raphael Dubois. — On the Khitiatnma bhittatum, Cuvier, by
M. Leon Vaillant.— Evolution of the nervous system and of
the vibtatile organ in the larvse of compound ascidians, by M.
Anipire Pizon, — On the lule of Anuebocyles in the Annelids,
by Emile G. Racovitza. Amxbocytts serve not only to deposit

NO, 1323, VOL. 51]

4?6

NA TURE

[March 7, 1S95 f

the cxcrciory fitjmem in ihe epi(iormi«, hut when necessary,
take up and digest for the l>enefit of the organism all the accu-
muliied reS' rve sobslancrs. — Valural and artificial proto-
-.ihylline, bv M. C. Timiriaz-ff. — On sime applications of
'Oceanography to Geology, by M. J. Thoulel.

DIARY OK SOCIETIES.

LoNi'ON.
THUnSDA Y. March 7.

Rqval SociKTV. at 4.30. — The Rubies of Kurma and Associated Minerals:
iheir M--k1c o( Occunencc. t )riKin. and Mciamorphoscs. A Contribution
to the History- of Corundum C. B rrington Brown and Pr»f. Jiidd,
F.R.S —I he Action of Heat upon Ethylene, Pan II. Prof. V. B. L-wes.
—On the Mea>urenient of Pressures by the Crusher-Gauge : W. Kcllner
and W. H Deering.

SociBTV OF An iiouariss. at 8,30.

LlNNEAS SoclBTV. at 8 — On the Genus Cupressus' Dr. Maxwell T.
Maflers, F R.S. — On the Insects, Ara-hnida. and Crustacea collected
during Mr. T. Bent's Extiedition to Hadramant, Arabia: W. F. Kirby,
Chas Gahan, and R. I. Pocock.

CHEMtCAL Socii;tv, at S.— DimethvlUetohexamethylcnc: Dr. Kippine. —
The Use of Ilinum Thiosulph.lte in Standardising Iodine : Dr. Plimpton
and T. C. Chortcy. — 1 he Magnetic Rotatinn of the Plane of Polarisation
of Light by Liquids: J.W. Rodger and W. Watson. — Irimcthylsuccinic
Add: Prol. W. H. Perkm. F.K.S., and Dr. W. Bone.
FRtDA Y, March 8.

RoVAL iNSTlTUTtoN, at 9.— The Physical Work of Von Helmholtz : Prof.
A. W. Rflcker, F.R.S.

PllvsICAL ^oclErv. at 5. — Exhibition, by Mr Naber, of a Voltameter.—
(t) The Fo -al Htliottat; (a) An Improvement in Siderostats Dr. G.
Johnttone Stoney, F. R S. Ota New Harmonic Analyser : G. L*. Yule.
— t>n the Electromagnetic Field ; H. N- .Allen.

RoVAL AsTROsoMtCAL SociBTV, at 3. — M icrometrical Measures of the
Diameter of the Sat-llitcs of Jupiter; Micrometrical Measures of the
Ball and King System of Saturn, and of the Diameter of Titan : E. E.
Pari.a'd.- Tran-it of Mercury, 1854 November 10 ■ \V. I-'. Gale; J P.
Thomson. — A List of Probably New Double Stars: k.T- A. Innes. — Double
Star M-a*u'cs; W. H Maw and J. Tcbbutt.— N 'tes on the Variable
Stars X and W Sagittx : Lieut. -(Lionel Markwick. — Note on a Su,;-
gested Formol Equatorial Mounting fora Modi6cd Newtonian Reflector:
Kev. C. 1). P. Davies,— On the Proper Motions of B.A.C. 793 and
Cephet 24(Hev.): W. T. Lynn. — The Wilsonian Theory and the Si any-
hurst Drawings of Sun-sp -ts : Kev. W. Sidgreaves. — Observations of
Encke's (^'imet : Royal Observatory, Greenwich. — An Apparatus tor
Mechanically Calculating Star C irreciions ; \V. E. Cooke. — Note on the
above Paper : Prof H. H Turner.

iKSTtTUTiON OF Civtt. Enginrers. at £. — TTic Coordinate System of
Surveying as employed in S'juth Africa : A, Struben.

MALACOLOOtCAL SociBTV, at 8.

Clinical Society, at 8.30.

SA TURD AY, March 9.

Royal Institution, at 3. — Waves and Vibrations: Lord Rayleigh,
F.R.S

RovAc Botanic Society, at 3.4.<;.

Essex KieldClub (at Stratford), at 6.30. — Notes on the Remains of
Pleistocene Miinmals found in the Neighbourhood of Ch-;! nsf ,rd : E. T.
Newi>tn, F. K.S —Note on the Section at Chelmsford in which the Mam-
moth anti other Remains were discovered, November 1894: T. V.
Holmes.

SUtfDAY. March 10.

SttNDAY Lecture SociETv, at 4- — Perpetual Motion: Douglas Carnegie,

MONDAY, March 11.
Royal Geographical Society, at 8 30 — Three Years' Travelling and

Fighting in the Oingo Free .State : Captain S. L. Hinde.
Akfiliatc^ PHOTOCKArlllc Societies (Cordwainers' Hall. E.C.), at 8. —

The Physics and Che <nistry of Development : Thomas Bolas.
Medical Society, at 8.30.

TUESDAY. March ij.
Royal Institijtion, at 3. — Internal Framework of Plants and Animals :

Prof C. Stew.nrt.
IttsTiTUTios fir Civil Encinbrrs, at 8.— The Kidderpur Docks, Calcutta :

William Duff Bruce. — Note on the Movement of the Walls of the Kidder-

pqr Dof-ki James Hrnry Ap) ,hn.
An"TH1I"I*olo.ical Isstiti-tk. al 8.^0. — The Changes in the Propnriiont

of the Human B >dy during the Pen pd of Growth Dr. Wingficld Hall. —

Notes fvn tie Lanitu.-i^e s,,ok n in Madaga-car J. T. Last.
Royal PiMror.KArHic Sociktv, at 8 — An Unconsidered Property of

Photogtaphi'- Lenses: T R. Dallmcyer.
Royal Victoria H all (Waterloo Bridge Road), at 8. — Photographic

Astr'iDomv : Mr. Knnbel.
Royal Medical ani> CHiRHHr.irAL Society, at 8 30.
Royal Horticultural Sociktv, at i.— The Diseases of Tomatoes and

Vines.

WEDNESDA Y, March 13.
Pharmaceutical Society, at 8 30.

SociBTTOF Arts, at 8.— The Meat Supply of the United Kingdom: E.
M'mtaiue Nclwn.

THURSDAY, March 14.
RoYA Society, at 4 30.

S'KIF.TYOr ANTIVI'ARIRS.at 8.30

Matkematical Socirtv, al 8 — The Invartanis of the Binarv f^uantic of
Unli'iiited Order : I'he President.— Certain tr Functinns: F H. Iacks,n.

iNsrtTu i->N OF Electrical £n<;ineers, at 8.— The Electrolysis of Gold:
N. S. Keith.

FRIDAY, March 15.
Royal Institution, at 9.— The Rarer Metals and their Alloys: Pr.

Roberts-Austen, C.B., F.R.S.
KpiDtMioLociCAL SorlETV at 8.— The Value of Eucalyptus Oil as a Disir.-

feciant in Scarlet Fever: Dr Joseph Priestley.
QuEKtiTT MlCKOsconc Club, at 3.

SATURDAY, March 16.
Royal Institution, at 3.— Waves and Vibrations: Lord Rayleigli.
F.R.S.

NO. 1323. VOL 51]

BOOKS, PAMPHLETS, atid SERIALS RECEIVED.

Books. —Elements of P.ithol.igical Histology: Dr. .\. Wcichsclbaum,
translated by Dr. W R Dawson (Longmans). — Le Lcman : K. A. Forel,
tome second (Lausanne, Rouge) — Everyt>ody*s Pocket Lawyer (Saxon). —
A treatise -tn Elementarv 'I rigonometry ■ Or. J. Ca^ey, new edition J
(Dublin. Hodg-s). — Apparcils Accessoires des Chaudicresa Vat'eur : Du-
dcbout and Cr neau (Paiis, G uthier-Viliar.s).— Tiaiie des Biiycles el
Bicycletes. C. B lurlet (Paris, GauihierViilars).— Conic Sections Dr. W. >
H. Besa t giK edition (Bell).— Organic Chemistry — the Katty Compounds;
R. L. Whilelcy (L -ngmansj. — Smithsonian Geographical T;ibles ; R. S.
Woodward (W.ashingt m). — Les Aurores Polaires A. .\ngot(l'aris .\lc.in).
— My Weat'ier-wise Conpanion: B. T. (Blackwood). — The Fauna of
British India, including Ceylon and Burma— Moths : G. F. Hampson,
Vol. 3 'Taylor and Francis).

Pamphlets. -Index to the Literature of Didymium, 1849-1893 (Wash-
ington)—Rrp-^rt of S. P. ' anglcy, Secretary of the Smith on. an Institu-
tion, for the Vear ending June 30, 1854 (W.ishiilglon). — Rrport on ilu
Opcrati ,iis of the D-partment of Land Records and Agriculture. Mai't
Presidency, f')r the Official Vear 1803-94 (Madras) — Zwei Neuc Par.idi
vogcl . A. B. Meyer (Be-Iin, Friedliinoer).

Serials.— Natural Science, March (Rail).- Cassell's Magazine, March
(Cass 11). — Contemporary Review, March(lsbister).— Hunianilarian. March
(Hutchinson). Bulletin dc la Acaddmie Royale des Sciences. &c., de Ucl-
gique. tis*^ Annie 3' sine, tome 29. No. i (Bruxellcs).— Zeilschrifi '
PhysikalischeChemie.xvi. Band, a Heft (Leipzig. Engelinaiin) — Scribi;
Magazine, March (Low). — Zeitschrift lur ^atu^wisseDschafte^, 66 B.uil.
5 and 6 iHeft. 67 Band, I to 5 Heft (Leipzig, Pleffer).— National Review, •
March (Arnold). I

CONTENTS. PAGE

The Ancestry of the Vertebrates. By W. N. P. . 433

A Cyclopaedia of Names 434

Our Book Shelf:—

Walker: " Varied Occupations in Weaving " . . . 435

Pease: " Horoe Breeding for Farmers."— W. F. G. 435

Hopkins; "Preparatory Physics" 43()

Chambers: " The Story of the Stars " 43*

" Aerial Navigation : Proceedings of thclnlernational

Conference held at Cliicago, August, 1893 " ... 43
Letters to the Editor: —

Liquefaction of Gases.— M. M. Pattison Muir . . .\y
Eleven-year Sun-spot Weather Period and its

Mulii[)les — H. Helm Clayton 43<

Abnormal .\tlanlic Waves. {IVilh Diagram.)— C. E.

Stromeyer ....... 43;

The Presence of a Stridulating Organ in a Spider. —

Prof Baldwin Spencer 43!

The SpeclruiH Top. — Dr. Dawson Turner .... 43!,

The Age of the Earth. By Lord Kelvin, P.R.S. . 43!!

Notes 4*

Our Astronomical Column : — 1

Spectroscopic Measures of Planetary Velocities . . . 44]'

The Satellites ol Mais .' 44.i

Eclipse of the Moon, March 11 44'

The Nile, liy Sir Colin Scott-Moncrieff, K.C.M.G.,

C.S.I 41

Observations of Sun-spot Spectra. {IVilh Diapam.)

By J. Norman Lockyer, C.B., F.R.S 41

Variation in Animals and Plants. By Prof. W. F.

R. Weidon, F R.S 41

Science in the Magazines 45'

University and Educational Intelligence 45

Scientific Serials 4-

S'lCietiei, 4nd Academies t

Diary of Societies

Books, Pampolets, and Serials Received 1

NA rURE

457

THE LIFE OF DEAN BUCK LAND.
The Life and Correspondence of William Buckland,
D.D., F.R.S. By his Daughter, Mrs. Gordon.
(London : John Murray, 1894.)

IN the early decades of this century Geology had not
established for itself an acknowledged place in the
circle of the natural sciences. With as yet no settled
philosophical basis, it offered a boundless field for indul-
gence in the wildest conjectures and the boldest specu-
lation. Its votaries were, therefore, hardly regarded as
serious students by the scientific men of the day. On
the other hand, they incurred much popular odium. They
had drawn such strange and almost incredible pictures
of what they averred to have been the past history of
the earth, so utterly at variance with all accepted beliefs,
that they were looked upon with suspicion by some,
sneered at by others, while by a large body of blatant
opponents they were openly denounced as freethinkers,
who, under the guise of natural science, aimed at the
subversion of all religion. It needed some courage to
be a geologist in those days, and still more to be a
champion of the new inquiry.

\mong the most prominent and effective of those who
lojd in the front of the battle and fought the hard fight
was William Buckland. No man did more than he to
raise geology from its depressed beginnings to the
dignity of a definite branch of natural knowledge. And his
name will ever be remembered with gratitude and affec-
tion as that of one of the clear-eyed, large-hearted fathers
of English geology. This proud position he gained by a
twofold claim. The amount, the wide range and the
intrinsic value of his original contributions to the science
would have been enough to place him in the front rank
of the leaders in that heroic age of geological discovery.
But it was not merely, perhaps not even chiefly, oy these
qualifications, admirable as they were, that he attained
to his unquestioned pre-eminence among his contem-
poraries. It was rather the unique personality of the man
which gave him his remarkable influence, irresistibly
engaging the sympathies and admiration of all who came
in contact with him, bearing down gently but firmly all
opposition, and gaining for him the affectionate esteem
even of those from whom he differed.

His solid work remains and can be examined and
weighed, and its influence on the progress of his favourite
science can be accurately determined. But that per-
sonal sway passed away with him who wielded it, and is
now only a memory. It has not yet been adequately
pictured for the comprehension of those who never felt
it, or who coming after have only heard feeble narratives
of it, together, perhaps, with some of the many quaint
stories still in circulation that illustrate it. At the time of
his death numerous appreciative obituary notices of him
appeared, some of them by personal friends who knew
him well, and mourned the loss of so much that was
bright, inspiriting and lov.able. Some pleasant recol-
lections of him by his son Frank were published in the
NO. 1324, VOL. 51]

last edition of Buckland's famous Bridgewater Treatise.
But some more detailed biography might have been
expected. He was a ready and copious correspondent,
and it might have been supposed that abundant material
must remain to furnish a picture of the man himself in
his daily life, in his family, in his lecture-room, in his
warm discussions with his friends, in his rambles with
his students, in his intercourse with farmers and masons
and labourers, and in his correspondence with many of
the most interesting men of his time.

It was therefore with no little expectation that we
received the volume of which the title is placed at the
head of this notice. We have read it with interest and
pleasure, and yet, it must be frankly confessed, with some
measure of disappointment. Mrs. Gordon deserves the
thanks of all lovers of science for the filial devotion and
affectionate enthusiasm with which she has prepared this
memoir of her father. We rise, indeed, from the perusal
of the book with a somewhat fuller knowledge of Buck-
land's career, and with a little more insight into that
personality which gave him his charm and his influence.
But the information is neither of the kind nor of the
amount which might have been looked for from the title
of the volume.

Nearly half a century has passed since Buckland was
stricken down by the malady which removed him from
active life, and after some eight years of sad seclusion
carried him to his grave. There can be few alive now
who remember him in his prime, and from whom remin-
iscences of the man could be obtained. Mrs. Gordon
appears to have done her best to procure such records
from surviving friends, and she has received several of
much interest. But it was from his own letters and
jottings that most of real importance was to be looked
for. The "correspondence," however, which appears on
the title-page, forms but an insignificant part of the book.
Long extracts are given from his lectures, his addresses
and his sermons. Those who want to know more of the
man himself would gladly exchange these citations for
the brief notes and the longer epistles, in which he con-
tinually unbosomed himself and told so graphically what
he was doing and thinking about from day to day. That
Mrs. Gordon has made such comparatively slight use of
such material must mean, we fear, that she has not been
able to recover it. In that case we must sympathise
with her disappointment. The task, perhaps, has been
too long delayed.

In looking over the nature and amount of the work
done by Buckland during his busy life, one is astonished
at the great e.xtent of subjects which claimed his
attention, and in which he laboured and wrote. At one
time he is absorbed in the study of changes of topography,
whether it be the valleys of the south of England, or the
solution of the chalk, or the destruction of the coast by
landslips, or the sculpturing of the Highlands and of
Wales by glaciers. At other times, or even when he
had some of these topographical questions in hand, we
find him hard at work upon problems in tectonic geology
— British or foreign — the structure of the Alps, the
geology of Nice, our south-western coal-fields, or the
coast of Dorset. But undoubtedly it was the pateonto-

458

NATURE

[March 14, 1895

logical side of geology that most fascinated him. And
what a mass of observations he accumulated in that de-
partment of the science ! Every grade of the animal
kingdom had an interest for him. He was passionately
devoted to living animals, and he made use of his know-
ledge of them and their ways in interpreting the remains
of their remote ancestors imbedded in the geological
formations. He would take endless trouble to satisfy
himself as to the habits of some living animal, in the
hope of thereby throwing light on the history of extinct
forms. Witness, for example, his rapid journey to the
Pentland Hills in Midlothian, for the purpose of exam-
ining the drained bed of a large reservoir, where he ex-
pected to find materials for elucidating the history of
old lacustrine limestones.

In those days geology had not become a science of
detail. There were new fields to be cultivated on every
side, and Buckland was the first to enter some of these.
His researches in caves opened up a fresh chapter in
geological history. And his chivalrous support of
.\gassiz. in the face of much ridicule, when he an-
nounced the former existence of glaciers in Britain, must
be recognised by all glacialists as one of the first steps
which led to the recognition and cultivation of glacial
geology in this country.

There was ever in Buckland's science a strong vein
of practical common sense. He was imaginative beyond
most of his compeers, and sometimes, perhaps, allowed
his imagination too free a rein, but he never lost sight of
the fact that geology has a very definite practical side,
and may be turned to useful account in many of the
affairs of daily life. He was an active farmer, in order
that he might try various methods for the improvement
of crops. To him we owe the introduction of coprolites,
so valuable a source of artificial manures. He never
lost an opportunity of preaching the true principles of
drainage, and he insisted on the value of geological
knowledge in all questions of water-supply. These are
familiar enough applications of the science now, but it
was largely through Buckland's influence that they were
recognised.

Of the man himself as he lived and moved, Mrs.
Gordon's volume gives a pleasing though hardly
adequate picture. His boundless energy and enthusiasm
were infectious, and led many a man and woman captive
into the geological fold. His industry enabled him to
carry on a busy scientific life, while at the same time
he had on hand enough of other work to fill up fully the
time of most men. His wide sympathies and large range
of knowledge broadened his grasp of his own special
science, and led him to see where he could find the most
useful collateral information. His eloquence as a
speaker and writer commanded the attention of his
audiences, and did much to make his subject popular.
His unweiried hospitality and his generous large-
handedness opened a way for him into the hearts of men ,
while his overflowing vivacity, his brilliant wit, and his
racy talk made him the central figure in any company
where he might happen to be. Truly there were gianis
in the land m those days, and no one of them deserves
to be more warmly remembered for all that he did, and
all that he was. than William Buckland.
NO. 1324, VOL. 51]

OUR BOOK SHELF.

The Birds of Eastern Pennsylvania and New Jersey.
Edited by Witmer Stone. Pp. 185. (Philadelphia :
Delaware Valley Ornithological Club, 1894.)

The Delaware \'alley Ornithological Club has only been
established about five years, but steps were taken shortly
after its organisation to compile a list of the birds
observed by the members in the vicinity of Philadelphia.
In this volume the important results of the club's orni-
thological investigations are brought together in a com-
pact form by the committee of three — Messrs. Morris,
Rhoads, and Stone — appointed to prepare the work. .A
list of the birds to be found in the Delaware Valley and
along the New Jersey sea-coast has naturally a limited
sphere of usefulness, even though it may furnish a work
of reference for ornithologists in general. But this
volume contains not only an annotated list of the birds
of the district to which it refers, and a bibliography of
ornithological literature relating to Pennsylvania and
New Jersey ; it comprises, in addition, outlines of the
knowledge of the geographical distribution and migration
of birds, thus giving it increased value. These chapters

April

urn.

1

2

3

4

5

6

7

a

9

10

II

12

13

14

15

IG

17

IS

19

20

100

90

r

'\

80

5

/

\

70

5

/

\

60

1

\

V

SO

h^

\

^

40

80°

/

'Nl

30

/

/

V

/

\

20

70°

(

/

J

10

J

—

0

60°

^

—

«_

^

<•

J

f

■5

A

r

J

«

50°

/

V

•&

-^

y

X

40°

B

Fig. I. — A, Migration Curve ; n, Temper.ilurc Curve.

will lead beginners in the study of birds to understand
the importance of simple observations.

The influence of meteorological conditions upon the
migration of birds is an important point, and one which
requires careful investigation. The records of the club's
observers furnish some valuable (acts for the study of
migratory waves or rushes, and their relation to
meteorology. It is pointed out that, during migrations,
the flight of birds is not uniform, but ismatlc up of a series
of waves or rushes and rests or lulls. The relation of these
rushes to temperature is well shown in the accompany-
ing diagram, reproduced from the volume. Ihe curve
A represents graphically the fluctuation of the April
migration of 1 89 1, based upon observations of the
Flicker, Chipping Sparrow, and Brown Thrasher; the
curve I! shows the temperature variation during the
month of observation, babed upon the daily maximum
temperature. The connection between the two curves is
very distinct, and it is especially interesting to observe
that the " bird waves " occurred a day or two after a
decided increase of temperature.

In conclusion, we think the Delaware Valley Ornitho-
logical Club is to be conf;ratulaterl upon its activity, and
Mr. Stone for this admirable addition to the lileratureon
the birds of Eastern Pennsylvania.

March 14, 1895]

NA TURE

459

Conspectus Flora Africa, oti Enumeration ties Planles

d'Afrique Par Th. Durand et HansSchinz. Vol. v.

Monocotyledoneae et Gymnospermeae. 8vo. Pp.977.

(Bruxelles, 1895 )
It may, perhaps, be asked why the fifth volume of a
■work should appear before the fourth and all the pre-
•ceding ones. Doubtless the authors were influenced
thereto by the fact that neither Oliver's " Flora of
Tropical Africa," nor Harvey's " Flora Capensis," has
reached the groups enumerated in the bulky volume
under notice. Certainly this course has the advantage
■of utility, and will be of great service in the elaboration
of the continuation of the works named. As an index
to the scattered literature of the subject, the present
volume is indeed invaluable. It covers all that may be
called African, including the Ailantic islands from
Madeira to Tristan d'Acunha. and the islands of the
Indian Ocean, from St. Paul and Amsterdam to Mauritius,
Madagascar, and Socotra. It is true, the geography of the
plants is not worked out all through so fully as Mr. C. B.
Clarke has done the Cyperaceae. For instance, the
characteristic grass of Tristan d'Acunha and St. Paul
ind Amsterdam islands, Spartina arundinacea, is only
recorded from the former group. In other respects, Mr.
Clarke's elaboration of the 800 Cyperaceae is by far the
most complete and thorough part of the volume, though
it is blemished by the introduction of a very large
number of names of new species without descriptions.

I5ut, leaving all criticism out, this volume will be wel-
' Dined alike by horticulturists and botanists ; by the
[inner, more especially, because it contains the petaloid
nionocols, so numerous in South Africa. Synonyms and
references to figures in the various illustrated serials add
to the usefulness of the enumeration. To give an idea
of the extent of this compilation, it may be mentioned
that the LiliaceK include nearly 1 100 species, belonging
to 67 genera. Aloe alone numbers nearly 100 species.
The Iridese are about 700 strong; Gladiolus being the
largest genus, with 1 43 species. < rchids also exceed
1000 species, belonging to 74 genera ; and 160 species
of Habenaria are enumerated. Palms are less numerous
than might have been expected, considering the com-
paratively large number in a small group of islands like
the Seychelles. Only 63 species are given, which is
about a quarter the number inhabiting British India.
This is largely due to the genus Calamus being repre-
sented by only one species in Africa, whereas there are
72 in India. W. B. H.

Li-cons de Chiinie. Par H. Gautier et G. Charpy.

I'Paris: Gauthier-\'illars, 1894.)
The general plan of the second edition of this work does
not differ essentially from that of its predecessor. The
introductory portion on generalities — dealing with states
of aggregation, laws of combination, equivalents and
atomic weights, physical and chemical transformation,
chemical equilibrium, the velocity of reaction, thermo-
chemistry, &c. — has been recast, and now occupies one-
fifth of the volume. In the descriptive portion, which is
concerned with inorganic chemistry only, Moissan's
work on fluorine, the diamond, and boron has been
introduced. It is characteristic of a French text-book
that even now it is deemed necessary to print alongside
each important atomic equation the corresponding
equation based on equivalents. In the same connection
it will be somewhat disconcerting to English students to
find that " Le poids atomique est i!gdl au poids
equivalent pour les elements suivants : . . . Pour tous
les autres elements, la valeur du poids atomique est
i double de celle de I'equivalent." In other respects the
book is well up to date, and contains much useful
information expressed with the clearness and precision
for which French text-books are deservedly famed.

J. W. R.

J NO. i3?4, VOL. 51]

LETTERS TO THE EDITOR.

[T/u Editor does not hold himself responsible for opinions ex-
pressed by his correspondents. Neither can he undertake
to return, or to correspond with the writers of, rejected
manuscripts intended for this or any other part of NATURE.
No notice is taken of anonymous communications.]

Variation and Specific Stability.

I AM afraid that in my anxiety to compress too long a state-
men', I did not make the points which I wished to bring
forward in the recent discussion at the Royal Society
sufficiently clear. I have therefore written out the following
summary : —

( 1 ) All organisms vary. That in doing so they obey Qaete-
let's law was suggested by Mr. Darwin himself more than
twenty years ago. He observes (Nature, September 25,
1873, p 432) : — " It is known from the researches of Quelelet
. . . ihat men may be grouped symmetrically about the average
with reference to iheir height. . . . We may presume that this
is the usual law of variaiion in all the parts of every species
under ordinary conditions of life."

(2) Prof. George Darwin supplemented this in a following
number (October 16, p. 505) with a very lucid account of the
principle. In this he says : — " We may assume with some
confidence that under normal conditions, the variation of any
organ in the same species may be symmetrically grouped about
a centre of greatest density."

(3) A well-known illustration is that of a marksman shooting
at a target. The dis'ribu'ion of his shots will follow the same
law ; they will be grouped round a centre of greatest density,
which is easily ascerlainfd, as it is the centre of graviiy of the
circumscribed figure. And on successive trials, it all ennriitions
remain unaltered, the position of the centre will remain the
same, though the positions of the shots will be different.

(4) No two individual representatives of a species in nature
are exactly alike. All differ in some respect. We may picture
the aggregate, however, as grouped with respect to any dis-
ctiminaiing character like the shots on the target. Our con-
ception of the species to which they belong is an abstraction
which we endeavour to represent in our museums by a specimen
which would be placed as near as possible to the centre of
greatest density. Such an abstraction we may call the mean
specific form.

(5) Returning to the case of the target, it is ohviius that if
some new condition be introduced, such a^ a wind blowing
transversely, every shot will be affected, and the centre of den-
sity of the system will be shifted. What is the analogous
result when we are dealing with the aggregate of individual
organi-ms representing "a species"?

Natural selection will come into play, to begin with. It
may be that some hitherto indifferent variation may be favoured
by the new condition. Others will be relatively hanHicapped,
and such a favoured variation will get the upper hand. It is
obvious that ihe result will be to shift the centre of density :
the mean specific form will have undergone a corresponding
charge.

(6) It is probable that so simple a result is not the usual one,
and wh.it actually takes place is much more complex.

Mr. Darwin concludes " that organic beings when subjected
during several generations to any change wha ever in their
conditions, tend to vary." (" Variation of Animal- and Plants,"
ii. p. 250.) I infer therefore, and all the lacs which have
come under my ob-ervali'>n confiruj it, that a chat'ge in the
external conditions, otherwise the environment, will provoke
seme variaiion in the organism, which I may call the stimulated
variation.

(7) It appears to me that fiom the Lamarckian point of view,
the stimulated variaiion ought to be immediately adaptive.
Froiu the Darwinian this is not necess.irily the case. It may-
be eiih' r advantageous or, at any rate, indifferent. ("Changed
conditions ^eneially induce mere flrciualing variability.''
Darwin, "Origin," 6ih ed. p. 131.) Prof. Ge ir>;e Darwin,
in ihe note above citel, traces out the result in the two cases.
In the former case, "with continual intercrossing;," the new
variai ^n will ge' the upper hand, and the ctniie of density will
De shifted ; in the latter it will, by continuous "weeding out,"
be, after a temporary displacement, eventually restored.

(8) This leads to the considcraiioii of the stability of the mean
specific lorm. Some species seem to yield preliy rapidly, though
with an appreciable inertia, to the influence of changed condi-

NATURE

LMarch 14, 1895

,cns ; o.^»s see. f-^ ^^^^-^l^l^'^^^^ll^.S^I^o^:^

ever, c«d the ""'.^Vh, been lately v:sed as an adverse a.gu-
do» n. Tb.s staHl. y ha, ^een la gel) ts .^^^ ^^^ ^„,h

„enMoo.gan.cevolu,.ong neraU^^.F^ -' -«=-'f '*'^ r""
influenced by it, ana s'ouiiy varieties. H'S expeti-

"•^X^;^?sr^^a!?K^>^'ap.eUhi..^a

S'osit'oD from »bich he never "...ca.ed h,»sc . ,

P The existence of specific ='»^' "{ 's',,'^-o„ D of >h^ E""'>>
Mr. Ca.r^.hers de>-oled his f <5d fi,^ •" f^',' ^^ asce.taired (acts
Aesooa.ion in .SS6 'f* "^''"'X /tre"! on the «ell-kno«n

on the sulject. He '""^P^i^Ke* Museums, as to the flora
aata. *bich a.e .nustrated.n the^Ke. Mus^^ ,^^^ ^^ ^^^^.^^

:\,i^^^5:ke.ld':vp--«> '"- p-''"'" '-- •'^"' ^"""

living «P'^-""='''^f:Vin<? illustration is afforded by the history

An even mo.e sinking '""^'"'],° f Ridgway's researches it

of sianda.ds of » eight l^'^J'^^'lJJs.^As ("Origin

appears that these *"« oiigiraiiy "^ finds (p. 182) that

of'^uirency and ^^ «;e!'^^='>-f ^^n he ba!ley corn." Further.
..,heT.oyg.a.n.snoth,rgmcre^han,hcb y

..in I28o(8td»ardl0 the penny * ^''f «heat" (p.

which . . . «"e =>. K„;n. '"'In Setttn.ber, 1887, 1 placed
.80). The ratio still obtans In berttn, ^^ '^^^J^.^,^

,n the opposite J"''-, j ^,, he ear 'and 24 grains ol bailey
and taVcn hem the n>'dst ol 'he 'Y' ^^%,^'|^'',, p.^ p.ticn,
;3ken(Km.icksofea.s8,o»nin the^ame^ „pe,imcnt ; each
r.ear Cambridge, and 1 tbrice '^f"'", j, jn"^ weight tuined

'r '*r..'F:xVheru"rd l:i ^^'^^uy , .f . e^i-

,he scale. ^ "''l".';' ""^g^ The same (act ol stability can be
3 T.oy e-^l"^ (P; \lll „,\d as standards ol «eieht. No
illusliated Horn ether -"os u,<: di<c<-td to veiy much

>,o.k.rg raturahst *''.' '\". .L%f v^ M, Car.utheis, that
„uaiiel »ilb the corclusion airivea at ry iji. _

doubtlul il tbeie is any ='t"'"J'',!,;,?" / however, pie(er to
b,okcn down by afpicp.ate -^'.t^^-^/ltS,"!;: n,e'an specific

^> '-' •'""Vitulo ble under F..maner,.l> umloim conditions.
(01m is 31 preciablj stable unoerp^^^^^^j^,

^^^h^'inrei^eir^f ^u:s'tr:.nhc'n";ises. how I this stability
.eceived the attcn.icn it <l^;'^"^„„^''i,e^;'rs evidently « ell

-^:^n:^■■::^^^ ^:^ ^as S^^ — "^-»''°" °^ ''^

^^Tn dealing ,i.h the f-.s re.er.ea to a-;,- -^;o >he Eg, pt.an
flora, he '^PW sa)s : '. In Ig)P>. ^," '^'^V,^ kno«, have
lfccu.>and yea.s. the "".'^' '°"f. ^.'. ^ •' fn ' ^th ed. p. .69.) The
..maincd aUo.uiely vn,lo,m. < /f ' B'" ° {^ ,hai under

i„.,l,ca.i.n, ibcvgh he f °'„^ T^" ^^^^'^^.''^^ ^
.uch c.utn.stantes <=^o.utitn is n abe)ance_ tendency

i, „.ms to me that we """^^^f"". ^.jf,, deve opment." Mr.
lowaids P-'-ft'"-" ,j';'*,hc cr.efa e pilncipl/with greater
D».*in '"'"'^^*f "hience of changed conditions accumu-
dtfiniteness. The 'r'"""" °' " ' "iotcies until u has been

,i,h De V.ln.o..r., cit.d by ^'';,f^"*'7„/- ^^nner whatever,

,he de.i.ed variation will poorer o' late, appear ^^^ ^

''r^'^ '"M^Dariii't'e" us^* • kfte^a do» n ger.ei'a.ion.
to liability. Mr- uarwin icMs variety would

„, -"■."•.'■--■;:„'»,p-,^:';^u!;r: i'liz, "m.^nt con.

""•»"> .f^r. oo»,r " ielH.rtili-aiicn," p. 460,) The same fact
■*"!;""■ .* M ■• bv the u.vivaldu.ingat Wasthall a cenlu.y of the

"— ^'i^ti;=r:hr^::::^aS::n;aSu;i;

l-;-e.^:avi onc-.liat". cltirction^ (C/. Da.w.n. - Life." ....
276.)

NO. 1324. ^'OL. 5U

(„) The case of wheat ^ V^^^^^'l^X^'Z it'mayt
worth while pressing the ^^-f "" ;°°„n<,,t i" "ower of
xemaiked that wheat has by "^ J""^'J?fVhe improved
variability Mr. C3">;^1-^ ;^°-'; '.ul^ hav'ebeen

varieties of our ceieals now under Senei individual

obtained almost emirely f'^"^^ ''^' "'","'" ?" „. 684.) Mr.
rlants." <7.."". A-- -X"; ^f.'-: 1 SI quotes" I'he authorities
Darwin (" Animals and Plants >• f>^) J°''^- ■ - ..-

I

Darwin (" Animals ana r.ams "ifi'vntea'byThe lake-dwellers
for the statement that <*'' «'^",\'^""^|i„J^' -admit that for
in Switzerland had «o--allgn.^

a very l°"g P"'°^ 'j;'^ to n e to p.ove nothing more than that

SuJS^^rasl^s,at|.^^h I ^Ijia^-;;^--

lie r is generally accepted tut ;hh Darwm ( .-^i- ..6>
i'antt pul liy hand on the" Xe^e. that the size of the gra.n

" irso'ThilTc°uld be unfavourable .0 its increase. De Can-

^JL ('"L'o ».re des plantes cultivees," p. 37o) ^'^8"^%''^,^
dolle ( ^°"j''^'-,,,,,,'u„i.piant as extinct, and suggests that

onginal sou.ce of '.'!f;^^"' ?'X^ „-,ayhave been the cause.

the attractiveness °f ''' fl^^''°l^^t^xrul cultivation it would

f «i'?,;s':ir/.vc: X.».d ,. ...., i. ...■*..

to the point. It s now p'e ) , ^^^,

Snilrma^S^^-^^Scut^ion, proves^o be
extremely variable. in-Doilant licht is thrown upon

given Mr. Darwin P""''"P'"'"';^„f„„,. ^cme organ in each
^ Prof. ^Veldon measures ve.y ""^"^^^^^"tnems are plotted
individual of a B-en popu lat.on^ The r^J-^-J^.^^^^^ .J^ „,h

cut akrg a ba.c ''"« ' !'\',;'"";7',,°,ed propcrtionalely by
each measurement ""j-'^^^^, X^ ,iie The summits when
lines d.awn re'F'"'l>':»'" '° '''f.'^^ ' ,d 3 />,•,;«<«./ <«'^'-- Fof

7ya„s .Sga. A-. ri'^ ^''^'^Ueims "a frequency cu.ve which
Piof. Karl Pearson (p- 72) '^""- , , ,,^.',i,„ -iior cuive, a
for practical purposes can - -Pj- ^ \?;,S: is only 1
noimal cuive. Such a ro ma c»i e _ 1^,^^,^ ,^^.^ ^,,,:^,,, .
another way of icp.esentirg '^/^ ";,"" ° p^o«e was the o.dirary
as I stated above, there «-,=■-■].' ^^J^^^^ ,,,:,, of measure- ,
law of variation, tor he »>'i^^ mobably .issume

r:hSi.-v:;ab,nrJuio;:r'fe^'^.oductionana

.';ffi:rt''re!^":nT:orL?rn^factcr in the stability I

problem. chosen (at random, except '

^ "About 70CO females ■ ■ • "* ' 'J,°i'"3*werc measured fn
as regards , heir si.e) and ;« '"j^';- ^^"^ ^-i,,, „,o.e of the
each. The results «"=. **'" .'^"""P „ a sample of .000
corresponding me.isurements, "^a'C >!P°

adult females liom •>^\'='"''; '°'.TXctive destruction" takes
The result was to '^ow that selccM^e a ^^^^^ ^^^

place in -''V''? ":';^^1.;of W don arnves at the conclusion
" mean specific fo.m. '.""■"!', action shoUd be sensibly
.. that the position of '"'""^ ""..f^ "'c ry"tem," is a condition
coircidcnt with the n^"" "'.'l f^ a large number of species,
which ■• n ay be expecled .'^ 1^?''' ^j.Vo eir present su/round-
which are sensibly in "l"'"'!' ■»^;^if,^;\' ,,,' „,« best." The
ings, so that their -""„^^'^ „'»<='„7 i.^fa";. i'n my opinion, de-
actual ^'••''■*''"';';j;'^' 'he most rema.kable achievements m
sfives 10 tank amcngsi iii>- ■

connection with the theory »' ;;o>" -"o.mal, P.of. Ka.l I'eanon
(,3, NVhen ^^ll^^'^y-^:^^Z7",^e particular foim o
.feis "the ""."'« »\*K'.\.„„:^;,n m^v in this case be able

natuial selection

. rf .^suie at a given time 01 sui.ic i^... . -"— ■- ,
lion/' The mathematician may in this ease be able

March 14, 1895J

NA TURE

461

to render assistance to the biologist of supreme imporlance.
■" The amount and direction of the abnormality will he indicated
if this [abnormal] frequency-curve can be split up into normal
curves." Analysis would in this way give us information which
we could perhaps not even guess at.

I agree with Prof. Karl Pearson that " resolution into two"
will be sufficient. The stress of natural seleci ion at any moment
must always be bciween the best and the ne.^ct best.

J n tolerably simple cases I have no doubt that the result of
Prof. Karl Pearson's labours will be to throw great light on the
matter. In more complicated ones we must look for some disap-
pointment in view of " the great variety of solutions which may
be suggested " 'p. io6). And the tentative discovery ol "com-
ponent normal curves " seems likely to be fallacious (p. go).

(14) I think it is important to insist that the importance ol Prof.
Weldon's present results has reference to the sta'^ilily pmb'em.
He is fully aware of Ihi? fact when he says that " they cannot
be expected to hold in cases of rapid change such as those
induced artificially by selecti ^n under domestication, or natur-
ally by rapid migration or oth' r |)henomena resulting in a rapid
change of environment." These will lead to abnormal fre-
quency curves.

(15) A few remaining points in Prof. Weldon's paper deserve
some remarks.

I entirely agree with him in minimising the value of " spor's "
in evolution. As ai;ainst Nageli and his followers, I see no
ground for believing in any innate progressive tendency in
organisms. When the organism is in stable relation with its
environment it will continue so indefinitely. That is the con-
clusion I deduce from the flora of Egypt, and other fac's which
have been cited of the same kind. Prof Webion seems to
me to have supplied this position with a mo>t im[)ortant proof
by establishing the "selective destruction" of variations ab-
errant from the mean specific form. When the environment
varies, stability is destroyed ; but it will be ultimite'y re-
established, though with a different centre, by the operation of
natural selection. The result is that the organism has under-
gone some permanent degree of change. As I conc-'ive the
process, it is one of continuous adju-tment of " slight " varia-
tions on one side and the other. But it is important to keep in
view that variation in the environment stimulates the variation
in the organism which supplies the ultimate material for adjust-
ment. That the amount of the adjustment at any moment i?
slight is not incompatible with its amounting to almost anything
we like in the aggregate, if sutficient time be allowed. We
might as well deny that a curve can be built up from its in-
finitesimal elements.

The value in this respect of sports may be easily overrated.
It appears to me that generally, so to speak, they attempt too
much anil overshoot the mark. The improbal)ility of a casual
sport being exactly what is wanted to bring the organism into an
advantageous relation to the environment at any particular
juncture seems to me very great. That such a thing may occur
is not denied, Ijut it can har lly be more than a "fluke."

(16) This is confirmed by the fact that in the vegetable kingdom
sports are rare, and they seem to have little power of holding
their own in competition. I instanced the cases of the occur-
rence of copper-colourtd and laciniate foliage in many trees, as
well as the occurrence of varieties with weeping and fastigiate
habit. It is well known that to some extent these are per-
petuated by setd. Put the existence of such forms would un-
doubtedly be transient if it were not for their perpetuation as
curiosities under cultivation.

(17) In museums it is u.uil to attempt the representation of
the mean specific form. The association of str kingly aberrant
specimens is interesting and often suggestive. But I do not see
that they illustrate more than the possibilities of variation and
the fact that it may be disc mtinuous.

(18) I placed upon the table plants of the feral type and of a
recent cultivated form of Cineraria ^ritnita from the Canaries.
The difference in habit and in the form and colour of the
flowers was enormous. This has undoui^tedly Iteen brought
about by human selection. As far as is known it ha-; been ac-
complished by the gradual accumulation of small variations.
The horticulturist has not troubled himself about the foliage,
which, though more luxuriant, has remained jiractically un-
changed, liut it must not be assumed that it is unchangeable.
In the case of the Chinese primrose, the feral form fro n north-
west China, for which we are indebted to Ur. Henry, has
palmatifid leaves rounded in outline ; but the distal lobes are

occasionally lengthened out. The horticulturist, as a matter of
fancy, working on this, has now split the type into two races,
one of which has palmatifid and the other pinnatifid leaves.
;\Iany botanists would, undoubtedly, if they did not know their
history, assign to such a dilTerent specific rank.

(19) I am not sure that I quite understand Prof. Weldon when
he says that "the statistical method is the only one at present
obvious by which [the Darwinian] hypothesis can be experi-
mentally checked." In the first place, I should myself hardly
call it experimental at all. In the next place, though I ihink
it will throw important light on the stability problem, iu the
important cases where evolution is actually taking place, the
mathematical analysis appears to me to be beset with very great
difficulties. We must not, therefore, expect too much from it.

(20) On the other hand, museums, as at present organised, do
not help very much the study of evolution. In the case of plants,
I doubt if herbaria will ever he able to present material in a
sufficiently compendious or complete form to be of much use.
The study, however, of extensive series of a few species of
insects ranging over the whole of a large geographical area,
such as Mr. Elwes has brought together in the case of butter-
flies, must, it seems to me, afford most important material for
future discussion. W. T. ThiselTON-Dyer.

Royal Gardens, Kew, March lo.

Do Plants Assimilate Argon?

It is a well-known fact that some plants are able to assimilate
nitrogen from the atmosphere and form compounds. Noiv, as
argon cannot be induced — at least up to now — by any known
process ol inorganic chemistry or physical science to enter into
a combination with one or more of the known elements, it
occurred to me whether that peculiar power which produced
the cell is no? able to form combinations with argon. The ex-
periment to grow suita'ile plants in an atmosphere of pureargon,
or argon mixed with pure oxygen, on a bed of pure sand, &c. ,
would easily settle the question.

If ihis experiment has not yet been made, perhaps you will
find space in y^ur paper for the above few lines.

Essen- Ruhr, March 6. E. Blass.

The first thing is obviously to find whether there is any argon
in a nitrogenous vegetable ; and experiments are now nearly
completed in my laboratory to see if nitrogen obtained from
peas contains any argon. Similar experiments are being made
with nitrogen from mice. In a few days I shall know the results.
But this is, of course, on the assumption that the process which
liberates nitrogen also liberates argon ; and it is by no means
certain. It should be rememiered that argon and nitrogen
have absolutely no similarity, and that their occurrence together
in air is a pure accident, due to the inertness of both.

March lo. W. Ramsay.

The Measurement of Pressures in Guns.

In a paper " On Methods that have been adopted for
Measuring Pressures in the Bores of Guns" (Report of the
Briti-h Association, 1894), Captain Sir A. Noble has remarked
that it seems to him " that there is no method so satisfactory,
depite its attendant labour, as that of making the projectile
write its own story" (p. 540). That might be sufficient for
smooth bore guns, where there was little or no friction in the
bore, but it is quie unsatisfactory when applied to ri/led gans,
and especially B.L. guns.

The two methods of experimenting now in use employ the
pressure g-aii<;e and xiie chronogni/i/t, both of which we will, for
this occision, sup,)Ose perfectly accurate. The pressure gauge
measures directly the pressure of the powder gas P, the quantity
wanted. The chronograph will measure P, the same pressure
of the powder gas, minus F, the resistance offered to the motion
of the shot by the rifling, the friction of the driving-band, &c.,
= P - V, where K is oiten very great. The difficulty i-. to see
how these t«o different processes can confirm one another, as
F is unknown and of great importance.

The only satisfactory method of determining the maximum
pressure of powder gas at any point in the b >re of a riJleJ gun
is to measure it directly, by the pressure gauge, which requires
many precautions to be taken, or by some other more simple
method. F. Bashforth.

Horncastle, March 9.

NO. 1324, VOL. 51]

462

NA TV RE

[March 14, 1895

The Velocity of the Argentine Earthquake Pulsations
of October 27, 1894.

In several recent notes in Nature (pp. 232, 371, 393),
attention has been drawn to the great Argentine earthquake of
last October 27, and to the record of its pulsations in Europe.
In one of these (p. 371) a rough estimate is given of the velocity,
but a more detailed one seems desirable on account of the great
Jistance traversed liy the pulsations.

According to M. Nogute (Comfits rendiis, vol. cxx. pp.
167-170), the epicentral tract includes Rioja, San Juan and
Mendoza. There is thus some uncertainty as to the exact posi-
tion of the spot from which the pul>ations started. In the
following estimate I have supposed it to coincide with San
Juan.

San Juan is about 312 km. from Santiago, and 11,600 km.
from Rome, the difference being li,2S8 km. The earthquake
was rcgistertd by a seismograph at Santiago at 8h. 50m. 26*.
p.m., Greenwich meantime. The slight preliminary pulsations
were recorded by the great seismomelrograph at Rome at gh.
7m. 35s., the first maximum at gh. 49m. 503., and the principal
maximum at gh. 55m. 40s. -Assuming that the first maximum
(or beginning of the larger pulsations) corresponds to the move-
ment which started the seismograph at Santiago, it follows that
the distance of 11,288 km. was traversed by the pulsations with
an average velocity of 317 km. per second.

It should be remarked that this estimate agrees very closely
with those ohtained for 'he same phase of the movement in the
cases of the Greek earthquake of April 27, and the Consianti-
nople earthquake of July 10, 1894 (namely, 321 and3'2okm.
per sec. respectively).

For the first slight movements recorded at Rome, Charkow
and Nicolaiew, we must admit either that the pulsations
producing them started some time before the great earthquake,
or else that they travelled with a far higher velocity. If they
left San Juan simultaneously with the larger pulsations (i.i. .it
8h. 48m. 48s.), their average velocity must have been
io"j8 km. per second. The horizontal pendulums at Charkow
and Nicolaiew also recorded these early movements, beginning
at gh. 8m. 36s. and gh. 12m. 6s. respectively ; soon after
which the curves more or less completely disappeared. San
Juan is about 13,625 km. from Charkow and 13,240 km. from
Nicolaiew, the average velocities to these places being therefore
1 1 47 and 9 47 km. per second. The latter obviously corre-
sponds tu a later phase of the movement.

Whether the slight preliminary pulsations start before, or at
the momerit of, the earthquake, is a question of the greatest
practical importance from the point of view of earthquake-
warnings. To aODwer it, one ol the Italian seismometrographs
or a h'jrizontal or bifilar pendulum should be placed beside a
seismograph in the immediate neighbourhood of the centre of
disturbance. C. Davison.

Birmingham, March 6.

The Society of Spelaeology.

The attention of jour readers has already been called to the
format on of this Society in Paris (Nature, January 3), the
promotion < f which is due to the action and enthusiasm of
.M. E. A. Martel, the author of the beautifully illustrated work
" Les Abimes," reviewed by Prof. Bonney in )our pages of the
28th ult. This book describes and illustrates a number of
extraordinary and often hazardous subterranean explorations in
the undergr .und caves .ind watercourses ol the limestone
districts of France, lie'gium, Auilna, and Greece. The
Society is intended to cirry on the work thus initiated by
M. Martel and his devoted co workeis in a more effective
manner, and over a wider area than has been possible by
private enierpri.«e. The formation of the Society, M. Mattel
writes me, is nf.w an accomplithed fact. About 130 gentlemen
of all nationalities, fome of whom bear well-known names in
the ranks of science, have signified their aiihesion. A pro-
visional code of rules has been printed and adopted, and a
meeting has already taken place, under the presidency of the
presidtnt-elect, M. F. Deloncle, Ileputy for the Uasses-Alpcs.

The first article of the rules slates the object of the Society as
follows: — "The Society of Sprlaeology is instituted in order to
ensure the exploration— to facilitate the general study— toco-
operate in the regulation or ullilisation — of subterranean
cavities of all sorts, known or unknown, whether natural or

NO. 1324, VOL. 51]

artificial ; to encourage and aid with funds investigations relat-
ing thereto ; in a word to popularise and develop in a way, at
once practical and theoretical, utilitarian and scientific, re-
searches of all kinds in the interior of the earth." The subscrip-
tion for ordinaiy members is fifteen francs per annum. It is
intended to publish a quarteily bulletin ; to a copy of which
each member will be entitled.

In order to fully carry out the objects of the Society, the pro-
gramme of which is a comprehensive one, more members are
required, and I sliall be glad to furnish any of your readers who
may wish to join the society with the proposal form or liulhtiit
(f Adhesion, or they may be olitained from M. Martel, General
Secretary, S Rue Mcnars, Paris.

M. Martel, I may say, is desirous of extending his investiga-
tions to the British Isles, if sufficient inducement be offered in
the exploration of some large cave, as yet unworked or imper-
fectly known, and where his apparatus of rope ladders, collap-
sible boats, ic, would be useful aids. Information on this head
will be thankfully received by me. Mark Stirrui'.

Bowdon, near Manchester, March 6.

Contraction of Trees caused by Cold.

The splitting of forest trees by frost is often ascribed to the
same cause which bursts a pipe charged with water when the
temperature tails below 32° F., namely, the expansion of the
water on turning into ice. Botanists know that this is not so,
but the splitting is owing to a contraction of the wood by frost,
similar, but in a less degree, to what happens when the wood
is dried. With the thaw the trees expand to their original
dimensions. Evidence of such contractions and expansions is
furnished by the measurements herewith.

For some years past, I have regularly taken the girths of a
number of forest trees during summer, in order to note the
amount of growth. To do this accurately I have to use a steel
tape, and of course to girth the trees at exactly the same place.
My experience, thus acquired in measuring to a nicety, is a
sufficient reason for confidence that the following figures are
substantially correct.

Girth of trees in

Octol>er 1894, when done

growing and before the

frost.

Girths,

February 8,
1895, 9 a^.m.
Temp. 3* F.

j Girths, March | Amount of

' 3, 189s, 3 p.m. I contraction

Temp. 39 F. , with frost.

No.

Inch.

Inch.

Inch.

Inch.

I Sycamore.

..26JI

26J

26i|

A

2 Sycamore.

..22i

22«

22J

t n

3 Sycamore.

■■■sr,

32U

33

A

4 Elm ...

..28,'„

284

28,v

h

5 Elm ... .

..22

21J

22

\

6 Elm ... .

•'9l"n

19?

I9A

ft

7 Ash ... .

■■4<>l\

45iil

461"-.

A

8 Oak ... .

.•4»i

42,",

42i

A

9 Oak ... .

• i7i",i

■7i

i7i".i

m

10 Oak ... .

-.VSV'n

34iii

35 A

A

11 Beech

.214

2 It's

2\\

A

12 Beech

■?,A

32,',

32*

A

13 Beech

aA

4>l

424

A

Bradford, March 4.

J. Clayton.

The Barrenness of Precambrian Rocks.

Referring to the paragraph in Natukk (February 2S, p. 423),
on the sudden a])pearance of a rich fauna in the Lower Cambrian
rocks, I should like to make a suggestion for the consideration
of geologists. May not the extreme poverty of organic remains
in Precambrian (Arch.x-an) strata be largely due to a scarcity of
carbonate of lime in the water of the Precambrian seas? The
Uriconian and Longmyndian rocks of Shropshire, which, at
the very lea^l, must include five miles of sediment, comprise
hardly a scrap of limestone. The same remaik will apply to
the Precambrian strata of Charnwood, South Wales, the main-
land of North Wales, and the great Torridonian group of
.Scotland. The Pebidian rocks of Anglesey contain liands of
limestone, it is true, but it in highly probable that they arc of
chemical origin, and not derived from oceanic waters. There
are, of course, plenty of limestones in the older .'\rch:ean rock*
of North .\merica, and a few of ihcm in the Lower Archa:ans ol

March 14, 1895J

NATURE

46;

Britain ; but the proof of their marine origin remains to be
written. T hey contain no undisputed organic remains. The
rocks in which tliey are intercala edarenot proved to be altered
sedimentaries. There were numerous animals living in the
Salopian area in the Longmyndian epoch, for their trails are
quite abundant in some of the slaty seams ; but, if there were
no carbonate of lime in the sea, there could, of course, be
little material to provide shells for its inhabitant'^. Numerous
creatures of many types might have been evolved, whose
soft tis^ue would lenve no traces in the rocks. In suc-
ceeding ages, as the forces of denudation cleared off the newer
Archaean, and cut down into panially decomposed crystallines,
abundance of calcic carbonate would be carried d )wn into the
sea. C. Callaway.

Wellington, Shropshire, March I.

The Artificial Spectrum Top.

In your issue of March 7, we notice a letter from Dr. Dawson
Turner, in which he says he has had a " Bcnha'n's .Spectrum
Top" m.ide on gla^s, by an optician, for the lantern, and
recommending others to do the same.

Will you allow us to slate that we have sold all rights in this
copyright top to Messrs. Peais, reserving to ourselves only the
sole right of maki ig them as lan'.ern slides, in which for.u we
have been supplying them for some time.

Theio;)s can be obtained from Messrs. Pears, and the lantern
slides from us ; any ons else supplyin;; either will, of course, be
infringing the copyright. Newton as'D Co.

RESEARCH IN EDUCATION}

NO branch of research work at the present day offers
greater opportunities, whilst none is more urgently
in need of original workers, than that which lies open
to the teacher in school or college ; and it is surprising
how small an amount of sound work is accomplished in
it — how little it is realised that there is a science of
education to be developed by persistent study, appli-
cation and research. An analytical habit of mind seems
to be the very last qualification sought for in a teacher —
such is the influence acquired by clerical instructors in
the course of centuries by the universal extension of
methods of teaching originated in the monkish cell and
cloisters, and wielded with but slightly diminished force,
even to-day, by their lineal descendants, whose voices
still preponderate in educational affairs. Conservative
and sheep-like — as we cannot fail to be if all our early
life be spent in an atmosphere of dogmatism — the slow-
ness with which we evolve and apply new ideas is
phenomenal. It cannot be that sterility is the outcome
of excessive labour in days gone by, and consequent
exhaustion of the soil ; still less, that it is owing to
absence of demand ; for it is only too clear that the
entire change in the conditions of life witnessed within
the century renders it necessary that our children should
be so educated that they may successfully grapple with
the new conditions, and it stands to reason that the
preparation which sufficed in the case of their forefathers
must be insufficient in theirs. This is now being
universally recognised, but all too slowly and imperfectly.
Thus the academic oration first on my list, delivered
only in September last, at Freiburg, by the Professor of
Anatomy, is a vigorous protest against the practice

\ " Ueber die V'orbildung unserer akademischen Jugend an den human-
istischen Gymnasicn." — Programm wodurch zur I'eier dcs Geburlsfcstes
Miner kj)nigltchcn Hoheil unseres durchlauchtipstcn Grossherzogs Friedrich
im Namen des acidcmischen .Senats die angehorigcti der Albert-I-udwigs
Uoiversitat einladct dcr gegenw.^rtige Prorector Dr. Robert Wiedersheim.
<Freiburg. 1S94.)

"The Teacher's Manual of Lessons on Elementary Science." By H.
Major, B.A., B.Sc, Inspector of Board Schools, Leicester. (Blackie and
Son.)

'■ Practical Lessons ill Physical Measurement." By Alfred Earl, M..\.
Senior Science Master at Tonbridge School. (Macmillanand Co.) '

"A Labiratory Manual of Physics and Applied tleclricity." Arranged
jnd edited by Edward L. Nichols, Professor of Physics in Cornell
University. Vol I. Junior Cnurse in General Physics, by Ernest Merritt and
Frederick J. Rogers. Vol. IL Senii r Courses and Outlhics ol Advanced
Work, by G. 1. Moler. F. Bedall, H. J. Holckiss. C. P. Matthews, and the
Editor. (New York and London : Macmillan and Co.)

VO. 1324, VOL. 5 l]

prevailing in the German " Humanistic " Gymnasia of
devoting an enormous proportion of the school-time to
classical studies, and the consequent neglect of draw-
ing, natural science, geography and modern lan-
guages, as well as of gymnastic exercises, which is
very strange, as he points out, when it is remem-
bered that the meaning of gymnasium is a place
for athletic pursuits. He especially complains of the
way in which exercises in classical style are insisted on
and monopolise attention, and strenuously advocates
their banishment from the three lowest classes at least.
He refers with feeling to the pressure which is brought
to bear in school and at home on the child to whom
such work does not appeal, and the unhappy state of
house and family on "style-days," remarking that every
one who, like himself, has had this experience in his own
person and that of his children, will sympathise with
this view. He tells us that his own bitter experience of
thirty-five years ago still follows him in his dreams, and
that he can never forget the encouraging words hurled at
him by the master of the "Prima" of the Stuttgart
Gymnasium when he had done a bad Latin exercise —
" You never in your life will come to any good, as sure as
my name is Schmid." Is not this too often the attitude
of our schoolmasters, and is it not too often forgotten
that the human mind, fortunately, will not in all cases
respond to one uniform system of treatment? Surely
the time must soon come when it will be the main
duty of headmaster and headmistress to study their
scholars, and assort them in accordance with their apti-
tudes ; when no headmaster will set down a boy as of
inferior intellect merely because he does not get on well
on the classical side, and cannot therefore be made use
of with effect as the winner of a scholarship at the
university — a course which some of our most noted head-
masters appear too often to countenance if report belie
them not. Fortunately we are not here so much the victims
of educational overpressure as is Germany under the
terrible influence of its military system, although there
is enough to complain of, especially in the case of girls'
schools, owing to the improperly large number of sub-
jects included in the timetable ; moreover, examinations,
such as the London University Matriculation, are exer-
cising a most insidious effect : and now that County
Councils all over the country are granting scholarships
on the results of examinations, it behoves us to be much
on our guard, and to take steps to secure that all such
examinations are so conducted that reasonably well-
taught and reasonably intelligent scholars can be sub-
mitted to them without any interference with the normal
school course. Prof. Wiedersheim, referring to the very
one-sided training given in the Gymnasia to the future
jurist, theologian and philologist, calls attention to the
importance to such students of some knowledge of
natural science in the following passage, which un-
doubtedly deserves our attention, as we suffer in like
manner ; " Kein Gebildeter vermag sich heutzutage
dem Einflusse, welchen die Naturwissenschaften auf das
Geistesleben aller Culturnationen gewonnen haben,
mehr zu entziehen. Die ganze moderne Weltans-
schauung, unser Leben und Denken, die Forschung auf
alien Gebieten — ich erinnere nur an das auch in der
vergleichenden Linguistik zur Geltungkommende gene-
tische und causale Element — stehen unter der Signatur
der inductiven Forschung. Mit diesem Umschwung hat
auch das humanistische Gymnasium zu rechnen, sollen
nicht Juristen, Philologen und Thcologen in ihrem
ganzen Bildungsgang einen Fehler aufweisen, der oft
nicht mehr gut zu machen ist." Hut this is nowhere
properly recognised. And yet Charles Kingsley long
ago dreamt of a day when every candidate for ordina-
tion should be required to have passed creditably in at
least one branch of physical science — if only to teach
him the method 0/ sound scientific thought. Ur. Percival

464

NA TURE

[March 14, 1895

has urged in Convocation at Oxford that the elements
of natural science should take their place in Respnn-
sions — side by side with the elements of mathematics,
and equally obligatory. The late Master of B.illiol, 1
believe, also recognised the importance of such a change ;
but the reformer who will carry it into effect is not yet
in evidence, and perhaps his services will not be
required, as the schools must soon do that which the
universities ought long ere this to have had the fore-
sight to enforce. We are, in fact, only beginning to escape
from the bonds of tradition, and it cannot be denied that
our release is being gradually effected— not through any
action taken by our ancient universities, but rather in
spite of them — mainly through the persistent efforts of a
small but untiring and resolute body of outsiders whose
position has yet to be made clear to the public, most of
whom undoubteily regard the teaching of experimental
science much in the way that the introduction of
pianos into Board Schools was regarded a few years ago
by a majority of Londoners — as something very nice for
those who can afford it, but as in no sense a necessary
element in the education of the masses. We, on the
contrary, contend that the human mind cannot, as a rule,
be completely educated by exclusive attention to literary
and m ithematical studies, and that lessons in experi-
mental science must form an integral portion of the
entire school course, because such lessons alone afford
the means of fully developing a side of the intelligence
which perhaps more than any other is of importance in
life — the faculty of observing and of reasoning correctly
from observation: with Kingsley, we desire that the
method of sound scientific thought should be taught
universally in schools, to the exclusion of dogmatism and
eyelcssness ; and we desire to inculcate habits of self-
helpfulness and handiness. The motto from Montaigne
adopted by Prof. Wiedersheim fully expresses the modern
view of education : " Es ist nicht ein Geist und nicht
ein Korper den wir erziehen sollen, sondern ein Mensch,
und wir durfen ihn nicht theilen." Hitherto more often
than not, we have cut him up into pieces, and thrown
the inost important aside. It is only in Germany that a
public address on such a theme can be delivered in
celebration of the birthday of a Royal Highness— here
we must fall back on the British Association ; but this
body has strangely wasted the unrivalled opportunities
which its organisation affords of appealing to the public
on such matters.

Fortunately, help seems to be at hand from a quarter
from which it was least expected, as the schoolmasters
are at last awakening to the necessity of reform, and
have themselves taken action which, if persevered in,
must be attended with most important consequences.
At the recent meeting of the " Incorporated Association
of Head Masters," which now numbers nearly 300
members, on the motion of Mr. C. Stuart, of St. Dunstan's
College, Catford, London, S.E., it was resolved

(a) "That the Association is of opinion that Examin-
ing Bodies should encourage a more rational method of
teaching science, by framing the syllabuses in such a
manner that the practical work required may be strictly
illustrative of the theoretical instruction given."

(*; "That it be referred to the General Committee to
appoint a small Sub-Committee, so that a rep >rt may
be presented to the next summer general meeting con-
taining detailed suggestions, which it is proposed to
make to Examining Bodies concerning examinations in
science."

As I ventured to point out, when speaking on these
resolutions, the consequences of their adoption will
probably be far greater than those who have accepted
them arc likely to have contemplated. Thoughtful
examiners have long been waiting for a sign : no one has
been more dissatisfied with their examinations than they
themselves have been, but it has been impossible for them
NO. 1324, VOL 51]

to examine much in advance of the teaching, as it would
obviously have been most unfair to candidates to make
them victims of a system for which they are in no way
answerable; and at most it has been possible to gradually I
give a practical turn to questions in subjects which can I
only be taught properly by means of practical lessons. ,
The gage thrown down by the headmasters will, there-
fore, certainly be uplifted forthwith by all examining 1
bodies whose work is not done in a purely perfunctory
spirit, and the schools will tind that of their own accord
and most properly they have brought about a complete
revolution in their own methods of teaching ; for if
they ask for proper examinations, they necessarily must
be anxious to see corresponding proper methods of
teaching adopted in their schools, and will provide for
their introduction. Nothing could be more gratifying
to those among us, who, during years past, have been
pointing out the necessity of introducing radical changes
and improvements.

A serious responsibility will now be cast on teachers, ||
and it is clear that if workers are forthcoming with minds '
imbued with the proper spirit of inquiry, there will be
ample opportunity of gaining distinction in the field of
educational research. There is clearly much leeway to be
made up, for although we are all agreed that every
branch of natural science must be taught practically, we
are, unfortunately, far from always practising what we
preach — the system of mere lesson learning not only ■
prevails far too widely and extensively, but is far too fre-
quently regarded with approval as all-sutlicient. The
practical and theoretical work are seldom, if ever, made ;
sufficiently interdependent — in fact, this is the blot on
which the headmasters have laid their finger. Even in 1
my own subject, chemistry, which is generally supposed
to be in a stronger position than most others, as it has
been taught practically from a considerably earlier date,
much misconception prevails, and we are cretlited with
having advanced far more than we deserve. Liebig,
the founder of the laboratory method of teaching,
appears to have taught chemistry — we are told
that when Hofmann became a student under him,
although a beginner, he was set to work at research ; and
we know that Liebig gave all his students problems to
solve. But the marcli of progress and, especially, the press
of numbers have long since led to the introduction of
the anti-research method which some of us irreverently
term test-tubing. Such and such is the case— do so
and so, and if you do so and so, this and that ivill
happen, are instructions so often dinned into beginners'
ears, that they become part of their very being, and i
they in consequence are ever afterwards unable to give j
a straightforward account of what tlicy have done, and .
insist, instead, on telling you, the teacher, what to do
and what will, not what does, happen. Nothing is more
rare in a chemistry examination paper than a straight- 1
forward answer, not in terms of if and will, showing that
the writer is describing from personal knowledge some-
thing that has been done. The true object of experiment-
ing is thus lost sight of as the habit grows of requiring
to know in advance what will be the outcome of any
particular experiment : the spirit of curiosity is rarely
awakened. At the same time the worst possible literaryi
style is encouraged, a real opportunity of developing ai
good one being most perversely sacrificed. Analytical!
tables were originally introduced with the laudablci
object of presenting knowledge to the student in a
systematic form, but g:radually we have allowed thentj
to pass from the position of good servants to thalj
of bad master — mainly because they offer so very con-'|
venient a method of keeping students occupied will'
a minimum of attention and hibour on the part of tli-
teacher and at a ininimum cost, as a few test-tubes aii'
weak solutions form almost the only stock in trade
(Quantitative work is also done in an almost equally per

March 14, 1895]

NA TURE

465

functory way, as a rule, with the object of qualifying the
student to do technical analyses, and the importance of
measurements in establishing first principles is never
taught practically, but is merely talked about : the result
is that only the few who study the subject professionally,
really grasp the meaningof the fundamental quantitative
conceptions of our science. It is not surprising that
under such a system, being helped over every stile, and
having no training in research methods, our students are
so very rarely properly educated. And altogether false
ideas have arisen also as regards the value of true
research work, this having been allowed in far too many
cases to degenerate into mere preparation-making, or
mere measurement work. There are many among us who
have recognised these shortcomings in our method, but
tradition exerts its all-powerful influence, and little short
of a revolution is required to reintroduce a truly scientific
procedure into our schools and examinations — to lead
teachers to recognise that the only proper method is to
make students researchers from the very outset. These
remarks are but prompted by the desire to acknowledge
that if I throw stones, 1 am fully aware that I dwell in a
glasshouse ; and especially to make it clear what is the
point of view from which I regard the problem before
the teacher of any branch of natural science.

The teaching of physics practically is of quite recent
introduction. When I was a student at ,he Royal
School of Mines, there were only lectures on physics ;
and when, about fourteen years ago, my colleague Prof.
Ayrton and I visited all the chief continental schools, we
found the practical courses in a very embryonic state.
Now, although we have nowhere a laboratory which will
compare in size or completeness of fittings with the
palace erected at Ziirich, practical physics is taught in all
science schools and colleges, and the London University
requires even candidates at the Intermediate Science
and Preliminary Scientific (IVl.H.) examinations to pass
a practical test. Many of the courses are very com-
plete. I shall not easily forget the pleasure which I ex-
perienced on the occasion of a recent visit to Prof.
Quincke's laboratory at Heidelberg from seeing there
the marvellously simple, but jet exact, apparatus used
in the practical course ; the insight into the inner mean-
ings of things afforded by his arrangements struck me as
most perfect, and led me to wish that it were possible to
teach my own subject so as to give the course an equally
high educational value. There are also nowadays
many admirable books from which the student may
gather instructions how to make experiments in the
various branches of physics — there can be no doubt, in
fact, that the practical text-books in this subject are
generally of a very high quality. But I venture to think
that they need modification in some not unimportant
particulars. Whilst in advance of the practical books at
the disposal of the chemist, inasmuch as they stand in
direct relation to the instruction in theory, being
intended, as a rule, as Prof. Nichols happily states in
the introduction to his first volume — to illustrate and
therefore impress more thoroughly on the mind the
principles and laws which have previously been taught
by textbooks or lectures, yet for this very reason the
attitude in which they place the student is a wrong one.
A "law" is dogmatically stated, and the student is told
how to verify it experimentally, so that the young
worker, instead of being led to inquire, is perpetually
told in advance what are the facts, and is instructed to
repeat the experiments merely in order \.o prove certain
things. Consequently, in physics as in chemistry,
students are far too little encouraged to find out things
and to help themselves — instead of becoming imbued
from the outset with the spirit of inquiry, they are led to
expect and require assistance at every step. While
galvanometer needles wag, they calmly put their hands
into their pockets, and it becomes very difficult to induce

NO. 1324. VOL. 51]

them ever to adopt any other mental attitude. Whilst
therefore our teaching is enormously improved by bring-
ing students into personal contact with the facts to an
extent altogether undreamt of even in my student days,
by the very wealth of appliances now at their disposal,
they are fast becoming spoilt — perfect sybarites, and the
self-helpfulness engendered by the rude and scanty
apparatus of days gone by is strangely infrequent. The
system apparently fails to engender or develop origin-
ality and powers of observation, however much it may
tend to train even well-informed and exact workers ; but
I imagine that little more than a change in the form of
the instruction is required, in order to make it impossible
to say of any one, " that he knows about all sorts of
things, but he can't do them," the only text, it seems to
me, worth preaching from at present. The principle it
embodies is the one of all others upon which the whole
practice of education must be built up, whatever the
subjects taught ; but it is undoubtedly one which has not
been kept persistently under notice, as it should have
been by teachers generally.

The habit of mind complained of, so characteristic of
all but a few gifted individuals among our students, is
probably largely engendered by the training they have
received during the early years at school ; and it is in-
cumbent on all teachers working in the field of educa-
tional research to do their utmost to develop methods
which will counteract the evil eft'ects of mere lesson
learning and desk work, as these cannot be altogether
dispensed with.

As illustrating — how not to teach elementary science,
the " Manual " first on my list must be assigned to a high
place ; no doubt the intention is good, the information
may be interesting and useful in its way, although often
very bald if not inaccurate, but such a book has no right
to figure as a " Manual of elementary science." It com-
prises instructions for object lessons, on every possible
topic, to children in the six standards of elementary
schools, in the form of very short chapters either of
" special information for the teacher " or " introductory
specimen lessons," and of " notes of lessons'' in which,
in parallel columns, the kind of question to be asked is
set out under "method," and the information to be im-
parted under "matter." As in all books of this class, far
too much is attempted. In the hands of a really capable
teacher — who would not need such a book, however, —
object lessons may be made of the highest value, but
even in such hands the tendency always is mainly to
impart information ; the kind of lessons that would be
given by the uninstructed teacher gaining inspiration
from Mr. Major's manual, is easier imagined than de-
scribed, and their educational effect could not fail to be
harmful. We are better without such "science," and
had better stick to the plain bread and butter fare of
'" prescientific " days, if we cannot teach in such a way as
to inculcate the practice of scientific method ; in fact, we
do not want "science" teaching of any kind introduced
into elementary or, indeed, any schools unless it take the
form of work done by the children themselves: in no
other wiy can the end we have in view — that of training
them to do, not merely to know — be achieved, and any
other kind of teaching must be a pretence and but an
encouragement of priggishness.

As regards the course of the future, there is no doubt
that much may be done in very early days to lead
children to take note of everything about them, to
describe what they see, and to collect and describe
common materials of every kind. Some slight prepara-
tion for the study of botany may also be laid at this
stage. But (he science lessons proper begin when the
children know enough arithmetic to measure and weigh.
All who have studied the problem practically are probably
agreed that simple measurement lessons must form the
foundation, and there cannot be a doubt that it is both

466

NA TURE

[March 14, 1895

desirable and possible to largely incorporate these with
the arithmetic lessons — to teach parts of arithmetic and
some geometry practically, in fact. Gordon's "Elementary
Course of Physical Science " is probably the type of book
which will be used with advantage at this stage, judging
from the success the course has met with in Board
Schools commencing with the fourth standard.

But the pioneer worker in this field is Prof. Worthing-
ton. His admirable little book,'' An Elementary Course of
Practical Physics," published in iSSi, well known to all
teachers of physics in schools, was expanded in 1886
into a larger work, ''A First Course of Physical Labor-
atory Practice." These books have been of the very
greatest service, and have probably rescued physics
from being made a cram subject in schools ; but they are
scarcely simple or comprehensive enough for such young
workers as 1 am contemplating. As they are intended to
be used in connection with lectures, the motive for each
experiment is rarely explained at sufficient length, and
unfortunately they have the fault common to all such
books, to which 1 have referred above, that the student
rarely approaches the experiment in the attitude of the
would-be discoverer.

Mr. Earl's book, although it deals only with measure-
ments of length, mass, and time, is of greater length than
Prof. Worthington's, but it does not need lectures to
supplement it. It has a short but admirable preface,
showing that the author has grasped the nature of the
problem to be solved, but it is one thing to do this and
another to succeed in solving it ; and here 1 think he has
been less successful. The style is far too didactic — the
descriptions are far too elaborate — the aim is too high,
and far too much is told, not enough left to be found
out : to use a homely phrase, which 1 trust will not be
misunder.stood, far too much fuss is made about the
work. Such work should be done by young children ; it
must not be postponed until the evil effects of desk work
have warped the scholar's mind, and natural curiosity
begins to die ouL But the book is far above such students.
What, for instance, is the valueof an introduction telling
us what science is, and why we learn it.' If taught to
work, children will very soon insensibly learn to ap-
preciate what they are doing, and nothing is gained by
pointing out to them, for example, that "e.'ich individual
stands a centre for himself of all things, knowing
that around him are centres of endless variety,
&c.'' Platitudes such as these are out of place
in an elementar)- text-book, and they are beyond children
of nine to twelve years of age, by whom simple measure-
ment work will ere long be done in schools generally.
In the next chapter, in like manner, we find at the out-
set a somewhat elaborate disquisition on the meaning of
the words standard and cjuantity, and a description of
how measurements of length are made, and then follow
directions for a series of exercises: children cannot grasp
such disquisitions, and are wearied by them, but most
of them will use a foot or centimetre rule with great
pleasure. This criticism may be applied to the book
generally— the introductory instructions are too fre-
quently high-flown, and too many refinements are intro-
duced into them and into the exercises. The book, in
fact, contains material enough both for a junior and a
senior course, and would be more generally available if
the matter were thus rearranged. But whilst objecting
to it on the score of over-elaboration and absence of
that simplicity of statement which is indispensable in a
book to be used by young beginners, taken as a whole,
and regarded from what I conceive to be the author's
point of view, it is a contribution to educational literature
of great value. The short preface alone is a manifesto
of singular importance, coming as it does from a teacher
in a public school of high standing. We find in it the
remarkable and, I believe, novel expression — the " scien-

NO. 1324, VOL. si]

tific sides" of Public Schools, one, it may be hoped,
that will soon take the place of " modern side," to which
so great a stigma is attached through the ill-advised
action of masters having sympathy only with classical
training — action which has led to the modern side being
often characterised as the refuge for the intellectually
destitute ; if the modern side once become the seat of
training in scientific method, a fair share of the intellect
of the school being allowed to it, there cannot be a
doubt that it will soon reap payment " by results "
sufticient to secure to it an honourable revenge. To
return to the preface, we read that care has been taken
to m ike the course logically progressive, the end in view
being to train boys to observe accurately, to reason
rightly, and to front nature with an open and inquiring
mind. That it must be admitted more generally than
is customary that the retention of facts should be
subordinate in scientific education to a sound
comprehension of them, a mind which has been
trained to observe and compare accurately being more
likely to acquit itself well in the world. That the right
way of learning is chiefly to be cultivated, the matter
being obviously less important than the method in
learning science, and a logical and inquiring habit of
mind being more valuable than the memory of f.icts and
laws, as it is better equipment for future research and
knowledge. It is urged that the course should afford
some training in correctness of expression and accuracy
of language, no insignificant part of scientific education,
although this is seldom recognised. Lastly reference is
made to the lack of continuity in work often prominent
as a defect, especially in the modern sides of schools,
and to the fact that much of the aver.ige " capacity of
learning" is never utilised, owing to frequent change both
of subject and matter. The book may serve in some
degree, the author suggests, to bridge over with safety
the distance between the laboratory and other class-
rooms, by acting as a Practical .Arithmetic and, to
some extent, as a Practical Grammar. Trite as some of
these remarks may appear to be, those who are aware of
the state of affairs in schools will know that, tested by
the standards which generally prevail, they are the
rankest heresy, but none the less heresy that must ere
long revolutionise existing beliefs and practices. In fine,
1 am inclined to regard Mr. Karl's book as the account
of an important research some results of which he has
described in a previous publication, this being his second
appearance as the author of an educational work.
There is the clearest evidence that he has set him-
self to work out a problem of which he was able
to realise, perhaps, only the general nature at the
outset ; and that, as so often happens in experi-
mental inquiries as experience is gained, the nature
of the underlying problem has been more clearly grasped
as the work progressed, and important modifications of
procedure have consequently been introduced. I look
forward with expectancy to his next memoir, in which
the results of his further studies will be presented to us,
I trust, in far less elaborate guise, so as to render them
available to the simplest understandings.

"The Laboratory Manual of Physics and Applied
Electricity," arr.mged and edited by Prof. Nichols, of
Cornell University, U.S.A., is intended as a college
course, and is stated to be the outgrowth of a
system of junior instruction which has been gra-
dually developed during a quarter of a century, and
I shall therefore venture to criticise it broadly
from an outsider's point of view, as though it were
a report on the results of an inquiry, with reference
to its general character and the arrangement of the
subject-matter. The first volume by Messrs. Merritt
and Rogers is intended for beginners, and, we are told,
affords explicit directions together with demonstrations

March 14, 1895]

NATURE

467

and occasional elementary statements of principles. It
is assumed that the student possesses some knowledge
of analytical geometry and of the calculus ; also that he
has completed a text-book and lecture course in the
principles of physics. Here we may at once join issue
with the authors. If, as is so frequently and indeed
almost always the case at present, the student come to
college knowing a good deal of mathematics and no
physics, the first assumption is a legitimate one, but it is
time that we began to insist that such educational
abortions should not be reared, and that girls and boys
be no longer allowed to grow up so ignorant that,
although they have learnt a good deal of mathematics,
they require to be told, when they come to college, how
to use squared paper, how to make simple experiments
illustrating the principle of the parallelogram of forces,
how to roughly determine density by weighing in water
and by means of a bottle — all of which, as well as a
number of other practical arithmetic exercises for chil-
dren, are included by Prof. Nichols in his first volume.
The incongruity is made still greater by the appearance
in the introduction, ten pages after the description of
the graphical method of representing results, of a some-
what elaborate discussion of " probable error" and the
application of the method of least squares. Surely, also,
no student nowadays should be allowed to complete a
text-book and lecture course before entering or practical
work — are we not seeking rather to invert this order.''
Were it not that the editor tells us that it is not expected
that the experiments will be taken consecutively, the
book might be regarded as helping teachers in the
choice of a properly graduated course of experiments ;
and with this confession before one, it is impossible also
to take exception to the somewhat extraordinary classifi-
cation of the experiments — an instance of which is
afl'orded by placing an exercise on the measurement of
the curvature of a lens by means of the spherometer first
in the course, at p. 26, whilst the determination of rela-
tive density " roughly " by weighing in water is relegated
to chapter ii. p. 80. Some indication of the editor's
experience as to the order in which the experiments are
advantageously arranged in a junior course would have
been valuable, as even to meet the exigencies created by
the simultaneous presence of a large body of students, it is
scarcely desirable to take physical exercises in any order.
Again, we are told that no attempt has been made to
provide a complete and sufficient source of information
for laboratory students — on the contrary, it has been
thought wise to encourage continual reference to other
works and to original sources, so that it is impossible to
complain of the book on the score of the incompleteness
of many of its descriptions.

The second volume is more interesting, logical and
original, and less fragmentary. It is intended for
students who have completed the "course" in vol. i.
and who are prepared to take up special work ; in it the
needs of those who are in training to become electrical
engineers have been specially considered- a sign of the
times — and it is for them especially that the parts treat-
ing of applied electricity, heat, and photometry have
been written. Parts i. and ii. occupy about half the
book, and comprise 53 direct and 64 alternate current
experiments, the intention clearly being to frame a sys-
tematic course suited to those who have gone through a
simple qualifying course in general physics. The in-
structions are very tersely worded, and but serve to give
general guidance — which is very desirable in the case of
students in whom it is desired to develop habits of inde-
pendence. Immediately after the electrical engineering
course, there is a very short section on electric-light
photometry. Following this comes the least satisfactory
section in the book, that on heat — dealing with the experi-
mental determination of specific heats, heat of combus-

NO. 1324, VOL. 51]

tion, vapour pressure, vapour density, heat of vapourisa-
tion, mechanical equivalent of heat, cubic expansion,
and measurement of temperature by means of thermo-
electric couples. Much of this might with advantage be
placed in the qualifying introductory course, and the
engineering student would gain little from the exercises
which do not properly find a place there. Moreover, this
section is grievously behind the times in many respects
— under vapour density, not only is the sole method de-
scribed "the classic one used by Dumas," but the pic-
ture is that which has figured in every text-book since
Dumas' description was published in 1826, showing a
stove which it would be impossible to find. Experiment
9 is headed, '• Use of the Favre and Silbermann water
calorimeter," an instrument which it is difficult to
imagine iniiseh-^ students. But Mr. Matthews, who is
responsible for this section, is clearly not a Rip
van Winkle, as he also describes the Bunsen ice
calorimeter and Berthelot's heat of vapourisation
apparatus.

Part. iv. of the second volume comprises outlines of
advanced work in general physics, based chiefly on re-
searches done in the physical laboratories of Cornell
University, written for the use of students who have
completed the routine work, and desire to enter upon
original investigation. This section will scarcely be of
value to outsiders, as every competent head of a labora-
tory has problems enough awaiting solution, and a text-
book of research is scarcely a much-felt want. Excellent
advice is given at the outset of this section, and yet it is,
in part, of such a kind as to bring out only too clearly
how much we are behind in our conception of what is
right and proper in education. At this stage — the com-
mencement of original investigation — says Prof Nichols,
there is a critical point. Further success depends upon
several matters which have been necessarily somewhat
neglected during the earlier periods. In the first place,
the student must acquire independence and self-reliance ;
he himself must face the experimental difficulties of the
problem upon which he may be engaged, and must
overcome them by devices of his own. Surely, we ought
not to wait so long — the first essential in teaching scien-
tific method should be to develop habits of independence ;
and if from the outset we lead students, as far as pos-
sible, always to take up the attitude of the discoverer,
there should be no critical point in their career, but
they should insensibly escape from leading-strings and
walk alone.

Being prepared specially for students at Cornell
University, the book will scarcely be used very widely,
and, indeed, is not suited for general use, I imagine ; yet
it appears to me to be of considerable interest to teachers,
as marking a distinct step forward in the evolution of
the text-book of the future. There can be little doubt
that those students, at all events, who have a technical
career in prospect, will be taught on lines such as are
indicated by the arrangement of the subject-matter
adopted by Prof. Nichols— that after going through a
qualifying introductory course, in which they gain a
general understanding of the main principles and of
method, they will devote their attention to the technical
study of whatever branch they may select. But it is to
be hoped that they will be so taught at school that the
introductory college course will not only be much
shorter than is at present necessary, but of a much
higher character ; and that, as I have said above, they
will be inquirers from the outset.

To carry such a scheme as I contemplate in this
article into execution, however, teachers of all subjects
must be trained in the school of research: surely this is
the keynote of future progress in education, indeed of
our national progress.

Henry E. Armstrong.

468

NA TURE

[March 14, 1895

NOTES.

TiiK Council of the Royal Society have fixed Wednesday,
May I, for the first Soiree of the Session. The Ladies' Con-
versazione will be held on some convenient day in June,
prbably the I2th.

We understand that Sir Joseph Lister, Bart., the Foreign
Secretary of the Royal Society, will be nominated for the
presidency- of the Liverpool meeting of the British Association,
to be held in 1S96.

Prof. W. C. U.nwin, F.R.S., will deliver the "John
Forrest " lecture this year, at the Institution of Civil
Engineers, on " The Development of the Experin1ent.1l Study
of Heat Motors."

.\ SERIES of Cantor Lectures, on Commercial Fibres,willbe
commenced at the Society of .Vrts, John Street, Adelphi, on
Monday next, by Dr. D. Morris, C.M.G. The subsequent
lectures will be on March 25 and .^pril i.

The 1S95 conference of the Camera Club will be held on
April 2 and 3, under the presiJency of Captain ;W. de W.
Abney.

The death is announced of Sir Edward Bunbury, the author
of " History of Ancient Geography." Mr. Alfred Giles, whose
name is well known among engineers, has also recently died.

At the meeting of the Royal Metcorologic.il Society, to be
held on Wednesday, the 20th instant, a lecture will be given by
Mr. W. N. Shaw, F.R.S., on "The Motion of Clouds con-
sidered with reference to their Mode of Formation."

The Council of the Society of Arts invite members to for-
ward to the Secretary, on or before April 13, the names of such
persons as they may think worthy of the .Moert Medal for 1895.
The medal, which is given annually in recognition of "dis-
tinguished merit for promoting Arts, Manufactures, or Com-
merce," will be awarded in May.

It is interesting to note, in connection with the subject of
Mr. Stromeyer's letter published last week, that Renter's cor-
respondent at San Francisco reports that vessels arriving there
announce the occurrence, on the 2nd insl. of an earthqu.ike in
the bed of the Pacific Ocean. The disturbance was accom-
panied by a loud roar, coming, apparently, from the sea, which
became covered with a mass of white foam, and subsequently
rose in numerous geyser-like columns.

Mr. Hvde Cl-ARKE, the author of numerous works and
memoirs on philology and mythology, and a member of the
Council of the Anthropological Institute, died at the beginning
of this month, in his cighiieth year. So long ago as 1S36 he
planned, as engineer, and also surveyed, the Gl.isgow and
South- Western Railway, with the Morccambc Bay Embank-
ment. He was engaged a few years later in acoustic tele-
graphy, and was employed to report on the telegraph sysiem for
India. His writings cover a wide range of subjects, but he was
best known for his contributions to philology.

Our attention has been drawn to a scheme, which owes its
initiation to Canon Tristram, and for which further sympathy
and support if needed. With the object of creating a more
general interest in the study of Natural History, an 1 to stimu-
late observation and research, it has been propose 1 to establish
a find for a medal or other prize to b: given annually by the
Natural History Society of Norlhumberland, Durham, and
Newcaslleupon-Tync, for the encouragement of ficl I work and
original observations in any branch of the suliject, whether
Botany, Geology, or Zoolo,{y. The prize will be offered for
the be*', essay evincing intelligent study of any of the common

VO. 1324. VOL. 51]

objects noticed in the fields or woods, on the moors, or by the
sea-shore, &c. ; competitors to bo residents in the counties of
Northumberland or Durham, or in Newcastle-upon-Tyne. It
has been determined to associate the medal with the name of
the late Mr. John Hancock. The capital fund required to pro-
vide the med.-xl will not be less than j^20O, towards which
amount over ^T'oo ha'i already been given and promised. Sub-
scriptions towards the fund may be sent to Mr. .-V. H. Dickinson
or Mr. M. C. Potter, Hon. Secretaries of the Natural History
Society, Newcastle-upon-Tyne.

The intention of the Ottoman Government to establish a
geodynamic observatory at Constantinople has already been
noticed in these columns (p. iSo). The new institution forms
a section of the Imperial Observatory, and is under the direc-
tion of Dr. G. .\gamennone, who has just issued a valuable list
of earthquakes felt throughout the empire in 1S94. The chief
interest of this catalogue centres in the accounts of the great
earthquake of July 10, and the detailed record of its after-
shocks. In the Observatory registers there are also preserved
many seismic notices relating to previous years, which are to be
edited and published at the earliest opportunity.

The seismic history of several districts in Italy has been
worked out with great care and thoroughness by Dr. Mario
Baraita. In his last paper (Rivista Geogr. Hal., Gennaio,
1S95), he treats of the earthquakes of Calabria Ultra. In this
province there are five well-marked seismic centres, or radiants.
From their position, and from the direction in which the epi-
centre is displaced, it is clear that they are closely connected
with the prominent faults which have helped to shape the pre-
sent surface features of the district. Dr. Baratta concludes that
(he earthquakes of 17S3 were produced by vihr.itions of these
faults, and that the shock of last November 16 was a repetition
of the terrible disturbance of February 5, 17S3, the areas most
strongly affected by them bjth being almost or quite identical.

The Council of the Marine Biological Association has
authorised the expenditure during the present year of a con-
siderably larger sum for boat hire than has been spent in pre-
vious years. Naturalists who visit the laboratory during the
coming season ra.iy thus expect increased facilities in their
work, and ample supply of material for their researches. The
Council, moreover, has authorised the director to offer free
tables in the Plymouth Laboratory to naturalists who will be
willing to render assistance in the arrangement of the collec-
tions in the museum, and in the collecting operations at sea.
It is to be hoped that many will take advantage of the efforts
which are bcin^ made to extend the usefulness of the magni-
ficent laboratory at Plymouth.

The Prince of Monaco has recently reported upon the first
scientific cruises of his yacht the Princesse .4Iice. The area
inves ijjated included the western basin of the Mediterranean,
the Straits of Gibr.aUar, and the Gulf of Gascony, along the
western oasts of Morocco, Portugal, and Spain, down to a
depth of 4S98 metres. Fiflyeight soundings and forty-six
temperatures and samples of sea-water were taken in thew
locali ies. The trawlmgs made by the Pri>uesst Alice in the
western basin of the Mediterranean merely confirm the known
poverty of the fauna of the great depths of this part of the
Meiliterrancan ; the Atlantic operations of the ship in 1894
Were unfortunately impeded by prolonged and violent northerly
winds.

Mr. J. Y. BucHANA.N, who has investigated the samples of
watrr taken by the Priiictste AlUt, finds that the density of the
Atlantic water is tl.e same along the whole south coast of Spain
as far as Cape Gala, owing to the existence here of a strong
surface curicnt sitting eastwards. From Cape Gata eastwards

March 14, 1895]

NA TV RE

469

nly the denser water of the Mediterranean proper is met with.
l"he difference between the ratio? of salinity to allialinity in the
ise of the Atlantic and Mediterranean waters is not very great,
utisclearly marked. ThemeancoelTicieiitof the Atlantic samples
examined by Mr. Buchanan was O'jooo, and of the Mediter-
ranean 04S75 ; while the minimum coefficient of the .Vtlanlic
-amples was greater than the maximum coefficient of the
Mediterranean. A possible cause of the difiference between the
Mediterranean and Atlantic waters is sought in the abundance
of calcareous rocks on the coasts of the former sea.

TltE first number of the new ChilianycH/H.-j/ oj Hygiene has
recently been issued. It is published under the direction of the
Institute of Hygiene recently established in Santiago, and
isprinted in Spanish. The present volume confines itself to
the history and development of the organisation of public
hygiene in general throughout Chili, and an account is also
given of the provision for official hygienic administration in
' 'rcrmany, France, England, and Belgium. One of the functions
xjrcised by the Santiago Hygienic Institute is the analysis of
substances for purposes of trade and commerce, and the grant-
ing of official certificates as to their quality. Considering the
enormously high death-rate of Santiago, which is stated to
reach 57 per looo, some reform in hygienic matters is urgently
needed, and it is to be hoped that the establishment of this new
bureau of Public Health may beneficially stimulate public and
private enterprise in this direction.

\Vf. could not have a better example of the insufficient
morphological descriptions which have become attached to some
microorganisms, than that afforded by Mr. A. Coppcn [ones
in his memoir on the tubercle bacillus, lately published. This
nvestigator has studied this microorganism for several years
ist at Davos, where he has had ample opportunity for the
- Ileclion of tuberculous material, and, after most elaborate and
painstaking researches, he considers that we are not yet in a
P'lsition to assign its correct morphological place to the organism
I nsociated with consumption. Mr. Jones is of opinion that it
j>njbably stands in close relation to the moulds, and that it has
far more right to be regarded as belonging to this category than
to the schizomycetes in the strictest sense of the v/ord. The
conclusions are based upon very careful observations, and the
memoir is abundantly furnished with beautiful illustrations.
The tetanus bacillus has also been seen associated with
mycelium threads, and Almquist is stated to have isolated two
bacterial forms which produced a branched mycelium. The
subject is a most interesting one, and well worthy the attention
of morphologists.

At the meeting of the French Meteorological Society on
February 5, an important discussion took place on the subject
of anemometry and the vertical currents of the atmosphere,
which have sometimes been recorded by the so-called clino-
anemometer. M. Ritter thought that the ascending currents
registered by those instruments were simply due to deviations of
the atmospheric currents by obstacles, such as the lower on
which the recording instrument was placed, which divides the
current laterally, and also inflects it in an upward direction.
M. Angot stated that such vertical currents do not rise to any
great height, in proof of which he said that on making the
ascent of the Pic du Midi, with an ascending wind caused by
striking the incline of the mountain, a number of small papers
thrown into the current only rose a few metres, and then ft 11
down behind the observer. These observations tend to modify
to a great extent the results of experiments on vertical atmo-
spheric currents, which have from lime to time been published,
and make it advisable for further experiments to be carried out.

The Report of the Meteorological Council for the year ended
March 31, 1894, has been recently presented to Parliament.
NO. 1324, VOL. 51]

In the department of ocean meteorology, the preparation of
current charts for all oceans have been regularly proceeded with ;
the Council have procured from foreign meteorological offices
nearly all the observations for the Pacific Ocean, with the view
of rendering the generalised results as trustworthy as possible.
The preparation and extraction of data for the south Atlantic
and west coast of South America, have also been actively prose-
cuted. In the branch of weather telegraphy and forecasts, an
important addition has been made by the receipt of daily reports
from two stations in the .Vzores. Forecasts are prepared three
times a d.ay, either for publication in newspapers, or for the
preparation of storm warnings, while during the hay-harvest
season, forecasts were supplied to farmers and others, and were
also widely distributed by the B lard of Agriculiure. The total
percentage of success of these agricultural forecasts reached 91,
being the highest yet recorded. .\mong the various publica-
tions the IVeekly Weather Report supplies a very complete view
of the chief meteorological changes over the greater part of
Europe ; considerable progress has also been made with the
rainfall tables of the British Isles, the total number of stations
for which the values for 1881-90 will be furnished is approxi-
mately 430, so that the general distribution of rainfall over
our islands will be well represented. Among the miscellaneous
researches carried on by the Council, we may mention the com-
parison of Dines's pressure tube anemometer, which shows the
wind pressure at each instant ; the vane is erected 93 feet above
the ground, and the recording portion is in a room in the Me-
teorological Office. Upon the whole, the comparison speaks
strongly in favour both of the reliability of this instrument,
and of the mean record yielded by the Robinson cup ane-
mometer, which has hitherto been generally in use, both in
this country and abroad.

It has often been observed that a bright scarlet uniform will
in a good photographic darkroom with ruby-glass windows,
appear perfectly white. On this subject Ilerr H. W. Vogel
made some interesting communications to the Physical Society
of Berlin at a recent meeting. Experimenting with oil lamps
provided with pure red, green, and blue colour screens, he
found that when white light was rigidly excluded, all sense of
colour disappeared to the observers, and nothing but shades of
black and white could be distinguished on objects in the room.
He further found that a scale of colours illuminated by red
light showed the red pigments as white or grey, which abruptly
turned into yellow, and not red, on adding blue light. Hence
a colour was perceived which was not contained in either of the
sources. Red and yellow patches appeared of the same colour,
so that they could hardly be distinguished. But the difference
was at once brought out by adding green instead of blue light.
How very much the kind of sensation experienced depends upon
the intensity of illumination is easily seen in the case of the
region of the spectrum near the G line of Fraunhofer. This
region appears violet when its luminosity is feeble, b'ue
when it is stronger, and may even appear bluish-white with
strong sunlight, so th.at the assertion often made that with
normal eyes a definite colour-sensation corresponds to a definite
wave-length, cannot be upheld. Herr Vogel comes to the con-
clusion that our opinion as to the colour of a pigment is guided
by our perception of the absence of certain constituf nts. Thus
a red substance is only recognised as such when light of other
colours is admitted, and we perceive its inability to reflect
these.

.\T the meeting of the Institution of Civil Engineers, on
Tuesday, iMarch 5, two papers, dealing with the transmission
of power by electricity, were read. The first, on "Electiical
HauLige at Earnock Colliery," by Mr. Robert Robertson, con-
tained an account of the general features of the colliery and of

470

NATURE

[March 14, 1895

those of its scams into which electrical hauling-engines had
been introduced to drive endless ropes, and to replace horse-
traction between the main haulage -roads and the working-faces.
The electrical generating plant comprised a dynamo for supply-
ing power to the electrical hauling-engines, capable, at a speed
of 620 revolutions per minute, of an output of loo amperes at
490 volts. Two electrical hauling-engines, of which the main
features were similar, were used. The two cables of s'randed
steel wire \ inch in diameter, operated circuits of 2l6o yards
and 1020 yards in length respectively. The cables were driven
continuously at a uniform speed, and the coal-hitches were
attached to or detached from them by a Smallman clip. The
efficiency of the plant as compared with the horse- traction,
which it had replaced, was also considered. The electrical
haulage-system in the Ell coal seam was capable of a daily out-
put of 400 tons. The daily output by horse-traction had been
180 tons, and to increase this to 403 tons, thirty or forty horses
would have been required, a number which could not have been
employed in the available space wiihout confusion. The daily
output of the electrical haulage-system in the main coal-seam,
which was not yet working at its full capacity, was between
150 and 200 tons. The yearly working expenses of the two
systems were compared, upon the results of one and a half
years' working, and were found to be ^4130 and ^^1990 by
borse-traction and by elec'.rical haulage respectively, showing
that an annual saving of ;/|'2l40 had been effected by the latter.
The total cost of the electrical installation had been CiV^-

In the second Paper — " Water-Power applied by Electricity
to Gold-dredging," by Mr. Robert Hay — an account was given
of plant which had been erected in New Zealand to utilise
water-power for generating electricity to be transmitted to
motors operating a drclge in different portions of a distant
river. The plant described had been constructed for gold-
dredging in the River Shotover, the course of which was for the
most part in rocky gorges through rugged country, accessible
only by tracks cut down the leading spurs and gullies. The
water was obtained at a creek i* miles distant from the dredg-
ing ground, and was brought by a race cut in the side of the
hill, or, in places where the ground was not suitable, in a
timber-flume, to a pressure tank at a level of 524 feet above the
pipes at the generator-house. From this tank to the wheel
employed the water was carried in rolled-steel pipes. The prime-
mover of the generating plant was a Pellon reaction water-
wheel, upon the buckets of which the water, from a nozzle li
inches in diameter, impinged at a pressure of 228 lbs. per square
inch. This wheel drove two series-wound dynamos working at
a normal speed of 700 revolutions per minute, each developing
a current of 40 amperes at an electromotive force of 650 volts,
or together nearly 70 h.p. The conductors, of a length of
two miles, were of No. 4 S. W.G. bare copper wire, and were
•npported upon insulators carried by cross-arms upon old 40-lb.
rails. The current was conducted to two motors in the dredge,
one for driving a centrifugal pump, and the other for operating
the buckets, winche.', and revolving cylinder. Two lo-ampcre
arc-lamps lighted the dredge at night, and were joined In
multiple-series with the motors, with suitable arrangements for
their control. The cost of the installation and the weekly
working expenses were jCtxx) and jCiS respectively.

At a recent meeting of the .\cademy of Science of Amster-
dam, M. Kamerlingh Onnes presented a paper by M. I,. H.
Sitrtsema, on magnetic rotary dispersion in oxygen. Since
making a preliminary communication on this subject, the
aothor has improved his apparatus in several details, and is
now able to examine Ihe gas under a pressure of a hundred
atmospheres. The oxygen employed was prepared by electro-
lysis. The measurements of rotation .are made by the wcll-
NO. 1324, VOL. 51]

known method in which white light, having passed through the
polariser, observing tube, and analyser, is then examined by
means of a spectroscope. \ dark band is thus obtained travers-
ing the spectrum, and the analyser is turned till this dark band
coincides with the part of the spectrum corresponding to light
of any desired wave-length. With currents between 35 and 65
amperes, the author is able to get rotations of from 3" to 4".
In the case of oxygen the results are very well expressed by

the formula 7 = -?^?^ U + °"°7^°^) where \ is the wave-

length in thousandths of a millimetre ; the mean error in 7
being ± 17-5. This formula is deduced from the formula

7 = -7 ( " ~ P ^ t" ) where « is the refractive index, given by

Mascart. A series of measurements were also made on atmo-
spheric air, and the values for nitrogen deduced by comparison
of these numbers with those obtained for oxygen. The
expression thus obtained for nitrogen is as follows : —
.y - 560-41 /, ,. o-3Z424\

An interesting series of experiments have been carried on by
Mr. T. Andrews, on the influence of stress on the corrosion of
melals, which may have considerable practical applications.
Bars of iron or steel were subjected to different stresses, ai \
were then placed in some electrolyte — jener.ally a solution cf
common salt — and the difference of potential between them
measured. It was found that tensile stress caused the produc-
tion of an average E.M.F. of 0'0l6 volt between the strained
and unstrained bars, the latter being positive. The effect of
torsional stress was to produce an average E.M.F. of 0'0I2
volt in the same direction. Similar results were obtained with
flexional strains. From the data obtained, the author deduces
a number of interesting conclusions which bear on the corrosion
of iron structures, for which we must refer to the original paper
in the Proceedings oi the Institution of Civil Engineers, cxviii. 4.

The ever-increasing precision in the study of the geological
distribution of fossils renders it necessary, from time to time, to
recognise that a well-marked litholojical division, though of the
greatest value in geological mapping, does not represent a
definite time-level, but may gradually rise or fall in time as it is
traced along its outcrop. This fact is well illustrated in England
by the-Crclaceous beds underlying the true Chalk, and some of
the questions involved have been discussed in two recent papers
in the Geological Afagaiitie. The first of these, by Messrs.
Jukes Browne and Meyer (November, 1894) deals with the
Upper Grcensand and Chlorilic Marl. They point out that
the latter term has been applied — and may justly be in its
lithological sense — to various horizons up to the zone of
Belemnilclla plena (as at Beer Head), and they propose that if
the name be retained it should be strictly limited to the zone of
Staunmema Carleri, which may be regarded as the bottom bed
of the true Chalk. They further point out that the well-known
Warminster fossils are a mixture of two f.iunas — the majority
coming from the summit of the true Upper Greensand, just
below Ihe Slai4ronema zone, though some are from that zone
itself, Ihe state of preservation being different in the two cases.
Thus the confusion between Chloritie Marl and Warminster
Greensand is due lo a mixture of fossils from different levels —
an accident that has often caused confusion in other formations
— and a complete revision of the lists of fossils from these
horizons must precede any further correlation. The second
paper, by Dr. J. W Gregory (.March, 1895), ''cals with Ihe
Gault and Lower Greensand. .\fter considering evidence
of various kinds, he comes 10 the conclusion that the conform-
able passage from sandy beds into clay rises in time as it passes
westward from Kent to Surrey, much as the upper limit of the

March 14, 1895J

NA TURE

471

clay sinks furl her west towards Wiltshire. The lowest zone of
the Gault in Surrey that has the typical clayey facies is equiva-
lent to the fourth or higher zone of the Folkestone Gault, the
lower zones being represented in the so-called " Folkestone
Sands." Dr. Gregory indicates the levels at which, in Kent and
Surrey respectively, the limits of the Albian, Upper and Lower
.■\ptian, and Rhodanian formations of the Continent can be
drawn ; but insists on the necessity of continuing to recognise
the old lilhological divisions side by side with the new palreonto-
logical ones. He also gives a critically revised and extended
list of fossils from the phosphate beds of Great Chart, near
Ashford, Kent.

The 1894 "Report of Observations of Injurious Insects
and common Farm Pests," by Eleanor A. Ormerod,
will not yield to any of its predecessors in interest, value,
or variety. The general character of these Reports is so
well known that it is unnecessary to dwell upon it ;
but the present part gives prominence to several con^i lera-
tions which have not hitherto received very much attention.
The first of these is the undoubted fact that almost any of the
12,000 species of insects inhabiting the British Islands, except
those which feed exclusively on other insects, may, under certain
circumstances, or when unusually abundant, become entitled to
a place in the category of injurious insects. Thus, the present
Report opens with figures and descriptions of three species of
/.ifidoflera—\he Eyed Hawk Moth, the Lappet Moth, and
the large Tortoiseshell Butterfly^which are not generally so
common in England as to be thought capable of causing serious
injury ; indeed. Miss Ormerod herself suggests that such pests
might easily be got rid of by inviting an entomologist to clear
I them off. One of the most important insect visitations during
I the past year was that of the Antler Moth (Ckamas graminis)
I in South Scotland, where the larvjE fed on the tender grass
j which sprang up over the districts previously devastated by the
vole plague. Several pages are devoted to hay mites, which
appear, however, though sometimes excessively abundant, to
cause little real damage. Other interesting creatures noticed
are the eel-worms (in her account of which Miss Ormerod has
unintentionally in part anticipated Prof. Percival's important
paper on the subject in Natural Siience for March, as fully
explained in an accompanying note), horse-warble, winter
gnats, wasps, &c. It does not appear to be quite certain
whether the horse-warble is the same species as the ox-waible.
Warble in the horse appears to be of much less common
occurrence than in the ox, and usually to occur only in small
numbers in the same animal. But this may be due to the horse
being a more carefully-tended animal than the ox. Two other
points of interest deserve notice. Several species of car-
nivorous ground-beetles are stated to be very destructive to
strawberries. More information is certainly required as to how
far so-called carnivorous insects will also eat vegetable matter,
decaying or otherwise. It appears that sea-gulls are some-
times in the habit of frequenting turnip- fields infested with the
Diamond Back Moth, and in one instance a farmer attributed
the destruction of his crop to the gulls. So easy is it to make
a serious error in discriminating between the farmer's friends
and foes.

A NEW and particularly convenient method of preparing the
unsaturated hydrocarbon allylene, CjH^, has been discovered
by Prof. Keiser and Miss M. B. Breed, as the result of an
investigation concerning the action of magnesium upon the
I vapours of the alcohols. Preliminary experiments showed that
when magnesium is heated with organic compounds such as
alcohols, acids, and ketones, a reaction of considerable energy
occurs at more or less elevated temperatures, accompanied by
incandescence ol the metal. The reactions between magnesium
NO. 1324, VOL. 51]

and the alcohols were then systematically studied. The mag-
nesium, in the form of filings, was placed in a porcelain boat,
and heated in a combustion tube through which the vapour of
the alcohol was conducted. At a low red-heat the magnesium
usually commenced to glow at one end of the boat, and the
incandescence was then rapidly communicated to the whole
quantity of metal, while large volumes of gas were evolved from
ihe tube. When methyl alcohol is employed the action is
extremely energetic, and the gases evolved consist mainly of
about four-fifths hydrogen and one-fifth marsh gas. The residue
in the boat is then allowed to cool in the vipour of the alcohol,
when it is found to have the appearance of a black coherent
mass. When this solid residue is placed in water a gas is slowly
evolved, and if a fe* drops of ammonium chloride are added,
the gas i-. liberated in a steady and moderately rapid current.
The odour of the gas resembles that of acetylene, but when it
is conducted through an ammoniacal solution of cuprous
chloride the greenish yellow precipitate of cuprous allylide is
produced, and with an ammoniacal silver nitrate solution the
while crystalline precipitate of silver allylide is formed. These
precipitates are highly explosive after separation and drying, a
temperature of 150° being sufficient to bring about their ex-
plosion. When they are treated with dilute nitric or hydro-
chloric acids they dissolve with evolution of allylene. Ethyl
alcohol behaves similarly towards heated magnesium, and the
black residue left in the boat after the completion of the reaction
is similarly decomposed by water with liberation of allylene,
the rapidity of evolution of the latter being also largely
augmented by the addition of a little ammonium chloride.
The most convenient' alcohol to employ, however, is propyl
alcohol, for the black m.agneiium residue is in this case decom-
p osed much more rapidly by wa'er at the ordinary temperature,
and the yield of gas is considerably larger. Prof. Keiser states
that this method of preparing allylene for lecture purposes, by
the reaction between magnesium and propyl alcohol, and
subsequent decomposition of the product by water, is far
preferable to the ordinary method of decomposing propylene
bromide with alcoholic potash. Most of the other alcohols
likewise afford magnesium residues which liberate allylene when
brought in contact with water, but the gas is rarely so pure as
that derived from the use of propyl alcohol.

The additions to the Zoological Society's Gardens during
the past week include a Macaque Monkey {Macactis cyno-
molgus, S) from India, presented by Mrs. Turner-Turner ; an
Azara's Fox [Canis azai;,'] from Brazil, presented by Messrs.
Edgar and Harold Turner ; four Amadavade Finches [Estrelda
amaiiiava) from India, presented by Mrs. Faulkenor ; a
Chukar Partridge {Caccabis chukar) from India, deposited ; a
Sykes's Monkey {Cercopithecus albigiilaris, 9 ) from East Africa,
two Red-crested Pochards (Fuligula rufina, i 9 ) from India,
purchased ; a Great Kingaroo (Macropis gigaiileus, i), three
Hunter's Spiny Mice (Acomys hunleri) born in the Gardens.

OUR ASTRONOMICAL COLUMN.
Spectrum of the Okion Nebula. — A full account of the
photographs of the spectrum of the Orion Nebula, which were
taken with Mr. Lockyer's 3oinch reflector at Westgate-on-Sea
in 1890, has just been published in the Philosophical Trans-
actions (vol. 186 A, p. 73.) Four hydrogen lines more refran-
gible than K are shown on the photographs, and in all S4 ''"es
have been recorded. The line near wave-length 3730, first
discovered by Dr. Huggins, is a very strong Ime, and among
other prominent lines, is the well-known chromospheric line at
wave-length 4471. It is shown that many of the principal lines
are coincident with bright lines photographed in the spectrum
of P Cygni at South Kensington, and with bright lines in plane-
tary nebulae and bright line-stars photographed by Campbell
and Pickering, so that a close connection of these bodies is

472

NA TURE

[March 14, 1895

established. Olher tables show a close relationship between
the bright lines of the nebula and the dark lines in the so-called
Orion s!ar>, of which Rigel and Bellatrix are typical examples.
The following are the conclusions to which the investigation
has led : (l) The spectrum of the nebula of Orion is a com-
paund one, consistinj of hydrogen lines low temperature,
metal. ic lines and fluting=, and high temperature lines. The
mean temperature, however, is relatively low. (2) The spec-
trum is different in different parts of the nebula. (3) The
spectrum bears a striking resemblance to that of the planetary
nebulae and bright-line stars. (4) The suggestion, therefore,
that these are bodies which must be associated in any valid
scheme of classificaiion is streng'hened. (5) Many of the lines
which appear bright in the spectrum of the nebula, appear dark
in the spectra of stars of Groups II. and III., and in ttie earlier
stars of Group IV. ; a gradual change from bright to d.Trk lines
has been found. (61 The view, therefore, that bright-line stars
occupy an intermediate position between nebulx and stars of
Group III. is greatly strengthened by these researches.

The Eclipse of the Moon. — The earlier phases of the
total eclipse of the moon on Monday morning were observed
under very favourable circums'ances in the neighbourhood of
London. The penumbra was not distinctly visible until about
ten minutes before contact with the shadow, and the whole disc
of the moon remained clearly visible, even at the middle of
totality, until clouds stopped observations about 4 a.m. The
parts deeply immersed in shadow were intensely red through-
out, and with the telescope all the principal foriraiions could
be easily distinguished. During totality the sky was excep-
tionally clear, and numerous ccculiationswereobserved without
difficulty. For half an hour after the commmcenient of totality
the following edge of the moon was pretty brightly illuminated,
and presented a striking contrast with the redness of the ad-
vancing etige ; at njid-cclipse, however, the whole of the disc
was veiy red.

It is reported that nearly 140 observations of disappearances
or reappearances of eighteen stars were secured at the Royal
Obstrvatory on Monday morning by the eleven obseivers who
watched ihc progress ol the eclipse.

The Nai'TIcal Alma.nac, 1898.— In the recently published
volume of the British Kphemeris for 189S, we note several
valuable additions. The places of eleven close circumpolar
.«lars, four of which are in the norlhetn hemisphere, are given
for each day of the year, and the mean places of fifty two
additional stars fur navigational purposes have been ad'led.
The improved explanations of the contents will also no duubt
be generally appreciated. The publication of an abridged
edition for the use of seamen is a step in the right direction.

PHYSICAL WORK OF HERMANN VON
HELMHOLlZy
1
HTHE career we ate to consider this evening was a career of
singular distinction. In days when the range of " natural
knowledge" is so vast that most workers are compelled 10 be
content if they can add something to one or two of the sub-
divisions of i.ne of the main branches of science, von Helm-
holti showed us that it is not impossible to be at once a great
tnnthemaiician, a great experimenial physicist, and, in the
widest sen»e of the term, a great biologist.

It was but eight months yesterday since he delivered his
last lecture ; it is six months to-day since he Hied, and the
interval is too short for us to attempt to decide on the exact
place which will I c assigned to him by posterity ; but making
all allowance for the fact that etch age is apt to place its own
great among the gteatesi, making all allowance for the spell
wbiih hs name cast over mmy ot us in the lectute-rooras where
we ourselves first gained some knowledge ol science, I am sure
thnt I only e\pre-s the vie*» of all those who know his work
he', when I jay that we place him in the very front rank of
those who have led the great scientific m'lvement of our time.
Tliis opinion I have now to juiiily. I must liy to convey to
you in sume >ixiy minutes an outline of the «ork of more than
lift y strenuous ) can, to give you some idea of the wide range
of the muhitold activities which were crowded into them, of the
marvellous insight with which the most diverse problems were

1 A di^otiriw delivered at ihe Royal ln«tiluiion,by Prof. A. W. Rijcker,
r.R..S., on Friday, March 6.

NO. 1324, VOL. 51]

attacked and solved, and, if it may be, some image ot the man
himself. The task is impossible, and I can but attempt some
fragments of it.

The history of von Helmhollz is in one respect a simple tale.
There are no life and death struggles with fate to record. His
work was not done with the wolf at the door, or while he him-
self was wrestling with disease. He passed through no crises in
which success or failure, immortality or oblivion, seemed to
depend on the casting of a die. He suffered neither from
poverty nor riches. He was a hale strong man on whom ex-
ternal circumstances neither imposed exceptional disabilities,
nor conlerrcd exceptional advantages, hut who, by sheer force
of the genius that was in him, passed on from success to suc-
cess till he was recognisei by all as the ailmirable Crichton of
modern science, the most widely cultivated of all students of
nature, the acknowledged leader of German science, and one of
the first scientific men in the world.

It is the more fitting that this evening should have been set aside
for the consideration of the work of Flelmhollz, in that England
may claim some share in his greatness. Hefore her marriage his
mother bore an English name — Caroline I'enn ; she was, as her
name implied, of English descent. His father was a Professor
of Literature in the Gymnasium at Potsdam, so that his early
days were passed amid that plain living and high thinking which
are characteristic of intellectual circles in Germany. The boy
did well at school, and when lite time came for choosing a
profession, his passion for mathematics and physics h.id already
developed itself. The course of his love for these sciences did
not run quite smooth. The path of his ambition was crossed
by Ihe haid necessity which in some cases checks, in otheirs
fosters, but in all chastens the aspirations of youih. He had
to make his livelihood. Science must be to him what the
Germans happily call a "bread-study." Medicine ofi'ered a
fair prospect of prosperity. Physics, in those days, was but
an in'clledu.il pastime. And so Ihe young man took his
father's advice, and became an army doctor. In this, as in so
many other cases, "the path of duty was the way to glory."

It is possible that if von Helmhollz had been what — with s
sad consciousness of the limitations it implies — t may call a
mere physicist, he would have played a greater part in the
development of some of those subjects, the study of which he
initiated or helped to initiate, but did not thereafter pursue.
It is possible ihat had he been a biologist, and nothing more,
he would have followed up the early investigation in which he
disproved the old theory that putrelaclion and fermentation are
chemical piocesses only, clearly indicating, if he did not
actually demonstrate, that the decay which follows death is doe
to an tiulbur-t of low forms of life.

He might thus under other circumstances have done work for
which he showed his competence, but which is now chiefly
associated with other names ; but it is certain that without the
unusual combination of wonderful mathematical power and a
professional knowledge of anatomy, be would never have
.iccomplislied the special tasks which it is his special glory to
have af-hicved.

His first three papers, however, hardly displayed Ihe fusion
between his various powers which was afterwards so remarkable
a characiciistic of his work. The first two were on biological
subjects. The third w.as ihe famous essay on the "Conserva-
tion of Force." I have told elsewhere the story of the
dramatic circumstances under which it was given to the world,
of the interest it excited among the members of Ihe Physical
Society of Berlin, Ihe refusal of the editor of Pi>i;f;tiidorll'f-
Annaltn to publish it, and the final triumph of Ihe author and
his views, {/'orlniglilly Kdir.v, November 1S94.) Helmholli
was not, and did not claim lo be an original author of the
doctrine of the con.servation of energy ; but two young men.
Sir William Thomson in Englaml, and Melmholtr. inGermaDT^
indeptndenlly, and within a month of each other, were tM
first persons who compelled the scientific world to regard it
seriously.

Thee is one interesting fact which connects this essay
diiectly with the Royal Insliiuiion. Four years alter it was
puldislcd, i' was placed by Hu Bois Kcynond in the hands of
one who was lost to ^cicnce in the same year as von Helmliollr
h msell — the lale Piol. Tyndall. Me was much impressed, and
has sp< ken o( ihc incident as bringing him face to Incc with the
great doctrine of the " Consetvniion of Knergy." {" Intioduc-
lirn 10 Popular Lectures by Helmholt?," translated by E.
Atkinson, 1873.) He translated the essay into English, and

March 14, 1^95]

NA rURE

47:

for many years made it his habit to place every physical paper
published liy Helmhohz within the reach of En^^lish readers.

And now, hiving brought you to the po^nt at which llelm-
holtz may be said lo have been fairly started on hii life's work,
let me first briefly describe his official career, before I consider
his work in greater detail.

When his extraordinary abilities became evident, he was per-
mitted to sever his connection with the army. At tweniy-seven
years of age he became Teacher of Anatomy in ihe Academy of
Arts at Berlin. In the next year he was appointed Professor of
Anatomy and Physiology at Konigsberg, and he held similar
posts in the Universities of Bonn (1855-58) and Heidelberg
(1858-71). It was not till 1S71 that his early love for physics
was finally rewarded. When the chair of Physics was to be
filled in the University of the newly-founded German Empire, in
Berlin, it was (eh that even in Germany — the land of specialists —
no better occupant could be found than one who was then in his
fiftieth year, and had been all his life a teacher of anatomy and
physiology. The choice was universally approved and com-
pletely justified, and von Helmholtz held this post till his dfath.

In this connection I am, by the kindness of .Sir Henry
Roscoe, enabled to show to you a relic of remarkable interest. It
is a photograph of the great teacher and investigator, taken at
the very last lecture that he delivered— that, namely, on July

7. 1894-

For some years, that is, from:the date of its foundation, von
Helmholtz was the president of the Physikalisch-Technische
Reichs-Ansialt in Chatlottenburg. This institution, founded
partly by the munificence of the late Dr. Werner Siemens, partly
by funds supplied by the State, has no precise analogue in this
country. It is devoted to the carrying out of systematic
researches on questions of fundamental importance to which a
long time must be devoted.

The most characteristic work of Helmholtz was, as I have
already hinted, that in which his knowledge of physics and his
knowledge of anatomy were both directed to a common end.
He dealt in turns with the external physical phenomena, with
the mechanism of the organs which the phenomena affect, with
the relations between the mechanical effect on the organ and
the sensations which it excites, and, lastly, with the connection
between the sensations in those simple cases which can alone
be investigated in the laboratory, and the complex laws of
.^.-sthetics and art.

The two books in which these problems were chiefly treated
were the "Physiological Optics," and the "Sensations of
.Sound." It is impossible to do more than lay before you a
sample which may afford some idea of the intricacy of the
problems with which he dealt, and of the pitfalls amongst
which he walked so warily. For this purpose I have chosen
one branch of his work on "Sound."

I have deliberately selected that particul.ar portion which has
been most questioned, that on which the verdict of most of
those who have sat in judgment on his views has been against
him.

In discussing this question I must give a general description
of the principal phenomena ; but if I were to attempt an
exhaustive catalogue of all the facts disputed and undisputed,
and of all the theories which have been based upon or upset by
them, not only would time fail me, but those who have not
given special attention to the subject would, I fear, become
hopelessly confused amid the chaos of opposing statements and
views. Another reason which urges me to be brief, is that a
few years ago Prof .Silvanus Thompson explained the whole
subject to the members of the Royal Institution, having kindly
consented to act as the mouthpiece of the celebrated instrument
maker, Konig, who has played so large a part in these con-
troversies.

Among the chief achievements of Helmholtz was an ex-
planation of the physical ditTerence between pairs of notes
which we recognise as concords and discords respectively.
When two neighbouring notes are sounded, alternate swellings
.ind fallings off of the intensity are heard, which are calleii
beats. These produce an unpleasant effect, which depends
partly on their number, partly on the relative pitches of the
beating notes. When two notes beat badly, ihtry foim an in-
tolerable discord. When they become separated by a wider
interval, the beats are so rapid that they cease to be unpleasant.

The sense of dissonance produced by many of these wider
intervals, such as the seventh (4 : 7), requires further explana-
tion. In general, the fundamental musical note is only the first

NO. 1324, VOL. 51]

and loudest of a series of so-called partials, whose vibration
frequencies are 2, 3, 4, &c. , times that of the fundamental,
and the consonance and dissonance of two notes is shown to
depend on the presence or absence of beats between important
members of these series. Thus in the case of the seventh the
frequencies of the octave of the lower note and that of the
upper note would be in the proportion 8 : 7, which are
sufficiently near to make the beats very prominent and
disturbing.

In cases where the notes are pure, that is, are not accom-
panied by upper partials, the explanation of dissonance is
based upon another phenomenon.

When two notes are sounded simultaneously a third tone is
often perceived, the frequency of which is equal to the differ-
ence of their frequencies. The number of vibrations of this
tone is equal to the number of beats, and as there has been con-
troversy as to whether the beats when they become rapid can
produce a note, and if so, whether this note is or is not the same
thing .as the difference tone, it is necessary to distinguish
between the two. This distinction is to be found in the mode
of their production ; but for the moment it is sufficient to re-
member that they may be distinguishable, and to reserve for
them two name=, viz. the beat-note, and the first difference
tone respectively.

Helmholtz drew attention to the fact that together with the
difference tone there is also produced a note, the frequency of
which is equal to the sum of those of the two primaries, and this
he called the first summation-tone.

Together with these he believed that there existed summation
and difference tones of higher orders, the whole series being
included under the name of combination tones. Our sense of
dissonance between pure notes was explained as dependent on
beats produced by the combination tones.

Up to the time of Helmholtz it was generally thought that
these tones were produced in the ear itself, and had no objec-
tive existence in the external air. They are thus often called
subjective, but as that adjective is usually reserved for impres-
sions produced in the brain itself, it is better to say that they
were regarded as c.ir-made. Helmholtz himself gave a theory,
which showed that it is probable that a membrane like the
drum-skin of the ear, which is forced out of shape by pressure,
and that bones, like those in the ear, which can rattle, would,
if acted upon by two notes, manufacture by their own proper
movements all the varied combinational tones which his theory
postulated. He therefore believed that combinational tones
were largely ear-made,

V'ou will observe that his theory of discord is quite unaffected
by the question whether the combination tones are or are not
sometimes objective. Provided only they are produced at all,
it is immaterial whether they are produced in the ear itself.
Von Helmholtz admitted that the phenomena we observe are in
most cases ear-made tones ; but h-.' also asserted that they were
sometimes objective, and could set bodies tuned to vilirate with
them in resonant motion. Ibis latter statement has been
denied with singular unanim.ily, sometimes, I think, without
due regard to the limitations which Helmholtz himself placed on
the conditions under which the objective character of the notes
can be realised.

All ordinary calculations .is to the production and mingling
of different waves of sound are based upon the supposition that
the displacements of the particles of air, or other body through
which the sound is travelling, are very small. If this is so, the
force which tends to restore each disturbed particle to its
ordinary position of equilibrium is accurately proportional to
the amount of the displacement.

In von Helmholtz' view, objective combination tones were
in general produced when the disturbance was so great that
this condition was no longer fulfilled. Violence is of
the essence of the explanation. Hence the siren, where
both sets of holes open into the .same small wind-
chest — the harmonium, in which two reeds alternately cIjsc
and open slits in the same enclosure, are the instruments best
suited to produce them. Of these the siren is the more efficient.
Von Helmholtz convinced himself that the coml)inatinn tones
produced by the harmonium are for the most part ear-made.
He expressly slated that "when the places in which the two
tones are struck are entirely separate and have no mechanical
connection, as, for example, if they come from two singers, two
separate wind instruments, or two violins" — to which wc may
add two tuning-forks — " the reinforcement of the combinational

474

NATURE

[March 14, 1895

(" Sensations of

tones by resonators is smill and dubious.'
Tone," translated by Ellis, p. 157.)

Now this reinforcement by resonators ha^ been allojether
denied by mo;t of those wh'> ha»e taken an interest in the
matter, while, if an exception is allowed, it is in favour of the
beats cf a disturbed unison, the observed effects being ascribed
to the beats, and no: to the difference tone.

Some writers make no exception whatever in their denial of
the objective reality of what may be broadly termed secondary
tones. Thus Mr. Bjsanquet, who made a most careful series
of experiments some fourteen years ago, stated that " the
ordinary first difference tone ... is not capable of exciting
a resonator. ... In short, thi difT.-rence tone of Helmholtz
... as ordinarily heard, is not objective in its character."
\Proc. Phys. So:, iv. 1S81, p. 233.)

Prof. Preyer, too, using very sensitive tuning-forks, found
that the differential tone given by two f jrks did not alTect a
fork the frequency of which corresponded with its own, except
in cases where the difference tone was itself a partial of one of
the forks.

It must be remembered that the assertions of Helmholtz as
to the experimental proof of the objective nature of the tones
were made with reference to those instruments which he regarded
as most likely to produce objective notes, viz. the siren and the
harmonium, and that, therefore, experiments with forks hardly
affect his position.

Let us now try with the siren whether it is possible to confirm
or to disprove the validity of his views.

For this purpose the rather bulky apparatus which you see
before you has been constructed. I should hardly have been
able to realise the idei embodied in it, at all events in time to
show it to you this evening, if I had not been favourably
situated in two respects. In the fi.st place, I have hid the
zealou; co-operation of one of my assistant^, Mr. Edwin Edser,
who has not only made all the parts of the apparatus that re-
quired to be newly made, but has thrown himself into the
investigation with the utmost energy, working at it late and
early, and making many valuable suggestions and improve-
ments. In our joint work we have been helped by some ol my
senior students, and notably by Messrs. Cullen and Forsyth.
In the second place, I have had at my disposal the magnificent
collection of acoustical apparatus in the National Museum at
Soath Kensington, some of which I am alloAed, by the kind-
ness of the Department of Science and .\rt, to bring here this
evening.

wave-length of light, the path of the ray which falls upon it is
shortened by a whole wavelet gih, and the position of each band
is shifted to that previously held by its neij;hlx>ur. If the fork
vibrates wiih an amplitude of this almost infinitesmal amount,
the bands will disappear, or will alternately appearand disappear
according to circumstances. The fork may therefore be used
to detect by resonance the presence of vibrations, the frequency
of which is 64 per second.

.1 firiori, there were two difficulties of opposite kinds which
made it doubtful whether the fork would be an efficient weapon
for the purpose for which it was to be used.

In the first place it would feel tremors of any sort, and it was
doubtful whether it would be possible to discriminate between
mere shakes and the vibiations which were to be studied. This
difficulty has been very largely overcome.

The table m which the app.-iraius stands rests on india-
rubber. On the table are a pair ol lihrary steps ; these support
two pieces of wood, which are heavily weighted and rest on
india-rubber b.iUs. From these two beams hang steel wires,
which carry india-rubber door-fasteners, and the-e in turn sup-
port two rods on which the paving-stone is placed. By this
alternation of elastic and of heavy bodies we can make the
bands absolutely steady, unless the disturbances are violent
The quiet movements necessary for wo king the apparatus, the
blow ing of the bellows, and the like, priduce no effect. On the
other hand, the shutting of a door in a distant part of the build-
ing, the rumble of a catt in the street, will cause the bands to
disappear. A great deal of the work on which we rely has
been done at South Kensington between midnight and three
o'clock in the morning. Trustworthy observations have indeed
heen made at other times, but it is only in the still small hours
thit the apparatus is at its best.

The second doubt was of a different kind. It was certain
that the instrument would be more or less shaken ; it was not
quite certain whether the fork would respond to vIbVations of
the given period. It is e.isy to set a tuning-fork in vibration
by resonance when it is mounted on a sounding ho'i, but in that
case the vibrations of the enclosed mass of air .are communicated
through the box to the fork. When the stalk of the fork is
held rigidly, a tuning fork is notoriously difficult to excite by
resonance. This objection is, of course, to some extent counter-
balanced by the extraordinary sensitiveness of the means of
detecting the vibrations, but it is necessary to supplement this
by other devices. The instrument used is a siren (s). In front
of it i< placed a hollow wooden pyramid, the narrow end of

-o.

The essential part of the appiratus. Fig. 1, is a tuning-fork, K, |
to one prong of which is attached a mirror, M, and to the other .
a square of thin wood, strengthened by ribs, which is of the same
weigh: as the mirror. The fork thus loaded has been compared 1
with one of Konig's large standards by means of Lissajous' figures.
Its frequency djcn not differ from 64 complete vibrations per
second by more than on; vibration in two minutes. The shank
is supported by a mass of leid, which in turn is placed upon a
paving-tlone. Upon thii stone ako rest the other mirrors
necessary for p-oducing Michelson's interference band*. The
mirror, M,, i« silvered ?.'. thinly th.ii hall ilie light which falls upon
it is reflected, and half is transmitted.

A ray proceeding from the lantern, i., will be divided at M,, into
two, which follow the paths 1 M,Mj\i,iiand i,M|MM,1) respectively.
Interference bands are thus produccl, which can be projected on
to a screen, so ai to be rendered visible to a large audience.

If the prong of the tuning-fork mives through the eighly-
th jusaodth of an inch, that is, through a distance equal to a half

NO. 1324 VOL. 51]

which IS near to, and is of the same area as the wooden plate
attached to the tuning fork. This serves to collect the waves
of sound, and to concentrate them on the fork. Behind the
siren is a large resonator by Koaig, timed to respond to 64
vibrations per^iecond.

In some respects the apparatus requires careful handling. Of
course if you blow down the collecting con: the fork may be
disturbed, and sometimes a particular note of the siren appears
to affect the fork for no very obvious reason. Probably ttie
resonance of the air in the cone, or the vibrations of the wooden
disk, may at times be the causes of such effects. We have, how-
ever, found that whatever they may be due to, they differ in
appearance from those proluced by vibrations synchronous with
the periodic time of the fork, and they can in general be got rid
of by a very .slight readjustment of the appataius. The fact
that our main conclusions do not depend on any such nicety, is
proved by the fact that the instrument has been se; up twice in
the laboratory, and once in the lecture-room in the College. In

March 14, 1895 J

NATURE

^75

each case all the experiments have been successful, and on one
occasion only were we troubled by a disturbance due to a
note (of about 253 vibrations) when sounded alone. A slight
readjustment of the cone, however, eliminated this effect
entirely.

Suih difficulties make it no easy matter to set up 1 he apparatus
in a huiry, and the most I can hope to do this evening is to
demonstrate to you the methods of u^ing i^ I cannot under-
take to make the actual measuiements before you.

It is, however, desirable 10 illustrate the sensitiveness of the
apparatus to vibrations of 64 per second, and its insensitiveness
to other sounds.

Provided the current of air does not travel directly down the
cone, organ-pipes may be blown just outside it without pro-
ducing any etTect. One of Konig's large tuning-forks may be
bowed stroni;ly without effect.

If, however, the exciting fork be tuned to 64 vibrations per
second, and if it be struck as lightly as possible with the
handle of a small gimlet, used as a hammer, the handle having
been previou>ly covered with india-ruiiber, the bands will
immediately vanish, though the note produced is often quite
inaudible, even to a person whose ear is placed close to the
fork.

Let the weights on the fork be shifted so that it makes
63 5 vibrations per second, then the resonating fork beats, and
the bands regularly appear and disappear every two seconds.

Having thus explained the construction and working of the
apparatus, let me show you how we have tested wheiher it
responds to a difference tone. When the proper rows of holes
are opened, the siren will give simultaneously the c of 256 and
the e of 320 vibrations. The interval is a major third, the
diflference tone is 64 vibrations. The pitch is determined by
the beats between the upper note and a standard tuning-fork
which gives e . Sounding the upper note al me no effect is pro-
duced on the interference bands, as the beats first appear, then
die out, and are finally heard again when the note given by the
siren is too high.

It could be shown in like manner that the 256 note alone
produces no effec', but if, when the standard fork of 320
vibrations and the upper note of the siren are judged to be in
exact accord, the 256 note be also produced, the bands im-
mediately disappear. Sometimes, of course, a small error is
made in the estimate of the pitch, and the effect is not instant-
aneous, but in every case the bands disappear when the beats
between the two notes are so slow that they cannot be
distinguished.

It is therefore evident that Helmholtz was right when he
asserted that the ditference tone given by the siren is objective.
It exists outside the ear, for it can move a tuning-fork.

( To be continued. )

JAMES WATT AND OCEAN NAVIGATION.^

TF it be asked what James Watt did during his long, busy,
and eventful life to improve ocean navigation, or to adapt
the steam en;;ine to the work of propelling ships, I am obliged
to reply that I am not aware he personally did anything, or even
that he concerned himself much about the matter. He took no
active part that we know of in applying or adapting his steam
engine to the \ ropulsion of ships. Tne reason probably was
that after his attention wa-; first directed to the subject of the
steam engine, or (ire engine, in 1759, his whole energy
was expended, first in improving the steam engine and
making its manufacture commercially successful, and afterwards
in executing ihe rrders that came for pumping and other engines
that were required for mines and manufactures. In the case of
most of the greatest mechanical inventions — -Watt's among the
number — it has not been the ideas or the inventions by them-
selves that have brought success, prospC'ity, or even satisfaction
to their owners. These results have had to be p.ainfully and
slowly evolved out of long and costly practical demon trations
and experience of the alleged merits of the invention, fames
Walt toiled, suffered ami endured for more than twenty years
after his discovery of separate condensation in 1765, before he
could see that his steam engine would ever bring him anything

' Abslr.icl of the Watt Lecture, delivered by Dr. Francis Elg.->r at
Greenock, on Janu.-iry j8.

NO. 1324, VOL. 51]

but disappointment, Io?s, and misery. It is highly characti ristic,
however, of Watt's ferule and original genius, and significant
of what he might have done to develop the marine engine at
the commenceiiicnt of its history, had he taken the mat'er up,
that upon Ihe two principal occasions we know of when he
applied his mind to the subject, he made very pregnant sug-
ge-tions. Thus, when Wait sent drawings of his engines to
Soho in 1770 for Mr. Bnu'ton to construct one for experiment,
and had been told that it was intended to make an entice to
draw canal boats. Watt wrote, " Have you ever considered a
spiral oar for that purpofe, or are you f>rtwo wheels? "and to
make his meaning clear he sketched a rough but graphic outline
of a screw propeller. This is, perhaps, the earliest suggestion of
a screw propeller, except that it was proposed by Daniel
Brrnoulli, 'he mathema'ician, in 1752. Again, in 1816, four
years after the first Clyde steamboat, the Comet, was built at
Port Glasgow, when Mr. Watt was upon his last visit to
Greenock, he went to Rothesay and back in a steamboat. W
that time the engineer did not reverse his engines, but merely
stopped them some time before the vessel reached hermooring-
place, and let her gradual'y slow down. James Watt, then an
old man of eighty, tackled the engineer of the boat, and showed
him how the engine could he rever-ed. He tried to explain
this with the aid of a foot rule, but not being successful in doing
it to the compl. te satisfaction of the engineer, he is said to have
thrown olT his overcoat and given a ( ractical demonstration.
Although Watt never took up the subject of s earn navigation
and never made a marine engine, still he was in reality its
originator, because he discovered and provided the means by
which it could be applied with advantage to the propulsion of
ships. Each of his great improvements upon the old engine
that worked by atmospheric pressitre and condensed its steam
in the cylinder — such as the separate condenser, the working
by steam pressure as well as by pressure obtained by vacuum, the
double action of the steam in the cylinder on both sides of the
piston, working the steam expansively, the centrifugal governor
for automatically regulating the speed of the engine, and
many others — was a direct adaptation for marine purposes.
There is one point in the history of shipping at which we
can draw a definite line between old and new when changes
were made so radical in the.r nature, and so rapid .and universal
in their operations, that all which came after is fundamentally
different from what existed before. The period of transition
falls in the early part of the present century, when the propul-
sion of ships by steam power was substituted for propulsion by
the wind — the motive power that h.id been employed from time
immemorial — and when the material out of which their hulls
were built was changed from wood to iron. The late-
ness of this period and its near proximity to the present,
is illustrated by the fact that it was not till after the
accession of H.M. Queen Victoria that steamships and ships
built of iron came to be regularly employed in ocean navigation.
At the close of the first third of the nineteenth century, the
over sea trade of the world was carried on with ships that were
all built of wood and propelled by sails. Only about 200 of
these were over 500 tons in burden, or much over 100 feet long.
Nothing approaching to such a rapid and complete revolution
as these two great changes brought about in the dimensions,
forms, and all the characteristics and qualities of ships, in the
conditions of life on board ship, and in travelling by sea, was
ever experienced before in the known history of shipping. All
the old ships of which we h.ave any knowledge — .and by old
ships I mean .all that existed prior to the introduction of steam
— were built and fashioned entirely by manual power,
with the aid of very simple tools ; and they were either pro-
pelled through the water by manual labour, or by sails that
could be worked in the simplest manner by the crew. One of
the broadest distinctions between the ships of the past that were
built of wood and propelled by sails and those of the present
that are built of iron or steel and propelled by steam, is that
everything had to be done in the former by the hand of man,
without any aid from machine tools or other modern Labour-
saving and labour-helping appliances. .\nd this was so both
in preparing the materials used in building the hull and shaping
them to their requisite form, putting them in position, r.istening
them together, and in working the ship at sea and handling the
sails so as to make the pressure of the wind most eflective for
propulsion. In modern ships, almost everything is, on the
other hand, done by steam-power in its various applications. It is
by this means the plates which form the hull are first of all rolled

4/6

NATURE

[March 14, 1895

and are afterwards cut. drilled, bent to the required roriii. and many
of them riveted ; and il is by steam-power also that ships, after
they are b liU, are propelled through the water, steered, pumped
and dr lined, ventilated, lightrd, loaded and discharged ; the
an ;hor is weighed, guns are trained, loaded and lired, ani all
the principal working operations are cirrietl on. There could
liave been no great difference in size between the ships of 2000
vears ago and the trading vessels of the la^st century. It is
the appli--alion of steam-power to propulsion and to manu-
facture that has enabled vessels to be jiroducci the dimen-
sions and pro|>ortions of which were formerly unapproach-
able. The cmploym-nt of iron and steel as the material of
construction would have been impossible without the aid of
steam-power; and it is the extra strength of hull obtained by
thrse means which cn.al)les ships to be built of the large
size that has now become common. Steam-power has thus not
on'y f imished a mode of propulsion certain and regular in
its action, and enabled ships to make their voyages with little
or no legarJ to wind or weather, but it has, in manufacturing
the raw material out of which ships are built, permitted the
dimensions to be very largely increased, and that not only with-
out risk and inconvenience, but with very great increase of
accommo lation. comfort, and safety. It is sometimes thought
that the largest ships arc essentially more unsafe than those of
smaller size ; the fact is, increa-e of size enables a vessel not
only to be made easier in her movements at sea and less affected
by the waves across which she is travelling, but it also
cnab'es the largest ships to be divided into so many separate
wa'er-tight compartments as to be practically unsinkable by the
action of ihe heaviest seas, or by the worst effVcts of a collision.
I do not say that all large ships are constructed so as to possess
this high degree of .safety, but many of the latest ones are, and
it is perfectly practicable to obtain in cases where safety is the
principal considerati'in. In small vessels the same degree of safely
could not always beohtaincJ. .Safety is aquality that can be much
increased by growth in dimensions.

Although James Watt may not have helped actively in
the application of steam-power to ships, it is really to
him and his inventions we have to look as the source whence
all the great moJcrn improvements i<i ocean navigation
have been derived. We tind in James Watt the typical
engineer. He was a great philoso,>her and a great mechanic.
He possessel just the combination of qualities and the tempera-
ment rrquisiie to enable a man to ascertain what may
be learned of the f.jrces of nature and their mode of
operation, and to utilise and apply these in the most direct way
for producing a required result. He formed that happy union
of what is commonly called the "theoretical" with the
" practical " man. For .as there was no better practical
mechanic than Watt in the countr)-, so was there no more
diligent student of the sciences related t j the subjects of his
work, or a more patient and thorough investigator of the
principles or theories upon which it depended. He tested
everything by experiment ; and it Is said thai when asked an
opinion of a novel invention or propo-al, his reply invatiahly
w»s, " Make a model." But having asceitained by experiment
all he could learn of the facts connected with any subject he was
inve»ti,;ating, he was never satisfied till the<e couli be explained
by some physic il law with which they could be shown 10 accord.
Hit meni >l aliijdc io*ards the great nuchanical prol'lems he
took in hand was th.11 of one engaged in a close and desperate
struggle with nature herself, qutslioning, cross-examining,
testing hyexperimcnn, attacking (r.im all sides, and refusing to
give in till he had succeeded in discovering the particular sccrtt
he required to know. A favouritesayingof his was, " Nature can
be conr|uered, if we can but find out her weak side."

We ihus see what are the qualities necessary \<i make a great
engineer. They are mechanical skill and experience, scientific
knowledge and capaciiy,i;real powers of observation an 1 original
invest igalion, energy, patience, and untiring perseverance. There
have been great engineers who have exhibited ceilain of these
qualities in a very high degree, l.ui none who possessed all
together in luch lull ineaoure and such harmonious blending
as we see in the caie of Watt. N > one man could otherwise,
in a lew years, have 1 ainfirmed so rude and imperfeci a machine
as the steam-engine was when Wall fii.si 1 jok hoi 1 of it into the
mo\\ perfect initiumenl that the working capabilities of the
time admitted. The proof of Watt's grcai power as a mechanic
and phil 'sopher combined are to he found in the fact that he
l>erfcctcd in lUch a thoit lime, wiiliin the limitations that were

NO. I5M. VOL. 51]

imposed by the quality of Ihem.nterials and the woikmen of the
day, the greatest work that has been performed by any engineer
of modern times.

We often hear the question asked by anxious parents or
.ispiring youths: How can my son, or how c.in I, ,is the
' case may bo, become an engineer or a nav.^l architect ? This
is sometime^ asked as though the making of an engineer or .i
naval .architect were perhaps a matter of three or four
j years' work in an office, combined with a certain
, amount of study of books, or attendance at lectures. There
i are few persons not belonging to one of the m.iny
branches of the engineering profession who know what this
question really means. Engineering — and when I say engineer-
ing, 1 include in the term shipbuilding and all other branches
of that grand profession, "whereby the great sources of power
in nature are converted, adapted, and applied for the use and
convenience of man " — engineering has of late become some-
1 what fashionable, and has attracted the notice of classes in the
community who at one time would have despised it as a base,
1 mechanic art, and turned their b.acks upon it. It has apparently
acquired the reputation of being a well-paid profession and of
being worth belonging to, in a money sense. To the general
body of inquirers who thus look to engineering as offering better
, financial prospectsihan the army or navy, than the law, medicine,
I or the Church — including some who think there might be a
I chance in that direction after failing to qualify for one of the
professions named — let me say that the prospects of success are
very remote unless he who enters upon it is gifted with
mechanical aptitude and skill, is willing to gain exjierience by
a long course of hard work, and at the same time has the
capacity, the taste, and the time for acquiring a sound knowledge
of the ma'.hematics and the physical sciences that relate to the
particular branch of engineering he may think of taking up.
Competition is now very keen in all departments of engineering,
and what prizes there m.iy be to strive for in them, can only fall
to those who are exceptionally gifted with know ledge, experience,
energy, and determinilion. An ordinary student or apprentice
who can only learn what some one teaches him, and h.is not
much faculty for imlcpendent observation, or for reflecting upon
and discovering the causes of the many things he sees going on
all around him, is never likely to be more than a subordinate in
the ranks of the profc.'^sion, a hewer of wood and a drawer of
water, for others who have greater power of acquiring know-
ledge, of thinking for themselves, of observing and investigating
closely and accurately the causes of defects and dilficuUics that
arise out of their work, and of devising the necessary means of
overcoming them.

If poets "are born and not made," I am sure it is equally
the case with a great engineer like James Watt. His
wonderful mechanical skill and ingenuity were natural to
him, and were the means of determining the course his life
would take. But even with all that, it is quite clear he could
never have made his great discoveries and improvements
h.ad he not been a naturally gifted and diligent student,
and acquired all the knowledge that was obtain.ahle
at the lime of mathematics and natural philosophy.
It is true that scientific study alone cannot make
an engineer ; but with the example of such a great mechanic as
James Watt before us, it would be very presumptuous for any
to say of himself that his own practical knowledge and judg-
ment arc sulTicicnt to make him a fully-qualified engineer without
studying what others have said or done upon the subjects of his
work, or the physical laws that underlie the whole fabric of his
practice and ideas. I would be the last to encourage any young
mantosupposc that ashort course of sludy,oreven great progress
in mathematics and the physical sciences, «ould justify him in
thinking himself an engineer ; but I am at the same time per-
fectly sure that no one, however great his mechanical skill and
ability might be, could ever become an engineer in the liuc
sense of the term without following Watt's example of
studying, thinking, and diligently acquiring all the know-
ledge of nature and nature's laws he can obtain ; and
applying such knowledge to Ihe better understanding of
the principles which reUate to liis work, and upon which
the degree of success he may achieve in i' depends.

One other remark with regard to James Watl. I have spoken of
the great benefits wc have dei ivcd in this country from Ihe appli-
caiion of his steanicnj;ine to ocean navigatiim I y drawing the
various parts of the world closer towards us, and converting the sea
into a bioad highway that uri'cs us to the different contincnit

March 14, 1895]

NA TURE

477

and islands upon it in a neighbourhood which is becoming
nearer and more inlimale every year. We often speak com-
placently of the advantage this is to our o«n country in parti-
cular— of what it has done in enormously increa.Mng the wealth
and prosperity of the rich, and amelioiating and biightening the
lives of the poor — in promoting the growth of our manufacturing
trades — in enabling food to be imported from abroad in large
and regular supplies at much cheaper rates than we could pro-
duce it ourselves in these islands, and in the great increase of
population that the growing prosperity of the country and the
easier conditions of life have thus brought about. All this is
true, and it represents an extent of change and of progress dur-
ing a short space of lime that we can only look and marvel at,
as being due to so large an extent to the results of one man's in-
ventions. But there are other feelings » iih which we do well to
regard the matter besides those of wonder and admiration, and
of self-.satisfaction with the great prosperity and the numerous
advantages the country has reaped. We have been favoured
above most other peoples by all these great changes, and
have been blessed in very bountiful measure. We must
not forget, however, that among the privileges we thus enjoy,
that of immunity from danger and harm is not included.
There are few pleasures or privileges to be had without alloy ;
and we now find, as a set-off against the benefits obtained
through the improvements in ocean navigation, that we have
much grc.-\icr responsibilities and difficulties in protecting our-
selves against darger, and in preserving unimpaired for the
fature the heritage of power and prosperity that '.las been
handed down to us. The same caujes that make ocean navi-
gation easy, swift, and certain for u^, make it easier also for any
possible enemies to attack us. The great increase of popu-
lation, due to the recent growth of wealth and prosperity,
requires for its existence constant supplies of raw material to bo
kept up fiom abroad, in order that our surplus hands may be
profitably employed in manufactures, and it requires also large
and continuous food supplies from outside m oider that it
may be fed. Hence the great problem of the time for this
country — how to protect ourselves against the dangers and
drawbacks of the new state of things, while enjoying for the
time its advantages and reaping its rewards ; and how to effec-
tually shield the vulnerable points in our armour that have
arisen out of changes and improvements which brought so much
good in other ways. It is upon the sea that any real danger to
England would arise ; and upon the sea it would have to be
met. Let us hope that the nation which has covered all the
seas of the world with its ships will not now fail in energy and
enterpiise, or be slow in providing and maintaining adequate
defence of what it has produced with such success, and out of
which it has reaped such rich reward. If we were to (ail thus
in our duties, and so shirk our responsibilities, the improve-
ments and benefits we owe so largely to the genius of James
Watt might, after all, prove a curse instead of a blessing ; and
we should be unworthy of the country and the race which
produced thegicat engineerwho taught his contemporaries, more
than one hundred years ago, how to manufacture Power.

UNIVERSITY AND EDUCATIONAL
INTELLIGENCE.

O.XFORD.— Mr. Francis Gotch, F.R..S., Holt Professor of
Physiology in Univer.-ily College, Liverpool, has been elected
to the Waynfleie Professorship of Physiology, vacated by the
appointment of Dr. Burdon Sanderson lo be Regius Professor
of Medicine. Prof. Gotch is no stranger to Oxford, having
been for some years assistant to his predecessor in the Waynflete
Chair.

Ca.mbridge. — Dr. W. S. Lazarus-Barlow, of Downing
College, has 1 een appointed Demonstrator of Pathology in the
room ol Dr. J. Loriain Smiih, who t as been elected Lecturer
in Pat heir gy at Queen's Colle^je, Belfast.

The Examination in Sanitary Science for the University
Diploma in Public Health wdl begin on Apiil 2.

Hitherto me of the conditions which had to be fulfilled
before ihc Science and Art fJcpaitment made payments to the
Commiltets i>f schoolsor classes, lor tl e inslruciion of smdtnis,
has been thai the farents ol a studenl should not have an
income exceeding /^4CO a year from all sources. A Blue-
paper now infoims us ihat the Lords of ihe Committee of

Council of Education have decided to enlarge this limit to
£,y>Q per annum. In future, therefore, the student on account
of whom a claim is made must belong to the category of
" persons in the receipt of not more than .^500 a year Irom all
sources, that is, who are .illowed an abatement of the income-
lax ; and their children if not gaining their own livelihood."
This example could be followed with advantage by the Tech-
nical Education Committees of those County Councils that
restrict their Scholarships to competitors whose parenis are in
receipt of less than ;if I20 a year.

NO. 1324, VOL. 51]

SCIENTIFIC SERIALS.

Bulletin de VAcadhnie Royale de Bel^ique, No. i. — Is the
declination indicated by a compass independent of its magnetic
njoment ? by Ch. Lagrange. According to Gauss's theory it
may be assumed that the magnetic axis of a magnet lies in the
direction of the lines of force of the field, whatever its magnetic
moment may be. But in practice it is found that the orienta-
tion of a magnet depends upon the strength of its magnetisation.
Since these systematic differences are not due to magnetic force,
they must be due to some other force, probably a force hitherto
unknown. Hence the magnetic chart of the earth calculated
by Gauss's theory cannot be considered rigidly correct. A new
constant must be introduced, depending upon the declinometer.
The author foreshadows an explanation of these facts, based
upon the " circulation of the ether,'' and intimately associated
with the physics of the globe. — Double decompositions of
vapours, by Henryk .\rctowsky. It is not necessary that two
substances should be dissolved in water to bring about their
mutual decomposition ; or their " ionisation,'' in terms of the
electrolytic theory, is not altogether dependent upon water.
Freshly sublimated mercuric chloride and flowers of sulphur
were placed in small vessels inside a Bohemian glass tube over
an organic combustion furnace. .\ current of pure dry hydrogen
was introduced, which on heating formed sulphuretted hydrogen
with the sulphur. This gas and the vapour of HgCl., gave a
precipitate of mercuric sulphide on the walls of the tube. This
reaction, which is contrary to Berthelot's principle of maximum
work, does not take moie time than the corresponding reaction
in water. To prove that it was a true double decomposition,
CO, was substituted for the hydrogen, when it was found that
the sulphur vapour alone was unable to attack the mercuric
chloride.

BiilUlin de l'.4iadc'mie des Sciences de St. Pclersbourg, fifth
series, vol. /, No. 4, 1S94. — Minutes of proceedings for
October last. — On derived lunctions of superior orders, by
N. Sonin (in Russian). — Crustacea Caspia : contributions to
the know ledge of ihe Carcinologlcal fauna of the Caspian Sea,
by G. O. Sars (in English, with eight plates). The Gammaridea:
are continued, and the following species, mostly new, are
described and figured : Gammarus Warpachtnvskyi^ mintiius,
macriiriis, comfrisiiis, siiiiilis, robustoides, crassus, ai'/imdalus,
and obesns, and .Vi/'liar^vides caspiits, Grimm. — On the trans-
formation of Periodical .\ggregates, mathematical paper by H.
Gylden (in German). — On Free Energy, by B. Galitzine (in
Russian).

SOCIETIES AND ACADEMIES.
London

Royal Society, January 24. — "Notes of an Inquiry into
the Nature and Physiological .\ction of Black-damp, as met
with in Podmore Colliery, Staffordshire, and Lilleshall Colliery,
Shropshire." By Dr. John Haldane.

Black-damp, sometimes also called choke-damp, or "stythe,"
is one of the gases frequently found in the workings of coal
mines. It is distinguished from fire-damp by the fact that it is
not explosive when mixed with air, but extinguishes flame ; and
from alterdamp by the fact that it is not the product of an ex-
plosion, but collects m the workings under ordinary conditions.
Like aiter-damp and fire-damp, it produces fatal effects when
inhaled in sufficient concentration. .\ further distinction has
been drawn between black-damp and white-damp, which latter
is described as capable of supporting combustion, while at the
same time acting as a jioison when inhaled.

The author has made a number of observations on con-
centrated black-damp from two pits, the first being in a fiery

478

NA TURE

[March i^, 1895

and the second in a non-fiery district. The conclusions arrived
at are as follows :

(i) The specimens of black-damp cons'sted when undiluted of
nitrogen containing an admixture of a seventh to an eighth of
its Tolame of carbonic acid.

(2) Air containing just sutTi:ient black-damp to exli'guish a
candle or oil lamp produced noimmeHia'ely sensi' le action on a
man. A mixture of a'out i6 per cent, of the Mack-damp and
84 percent, of air exlingui>hed candles and lamps, whereas a
mixture of about 60 per cent, of the black damp and 40 per
cen'.. of air wouid be required to produce immediate danger to
life.

(3) The lUngerous physiological action of black-damp is due
to deficitncy of oxycen, not to excess of carbonic acid. The
cflecl first appreciable when increasing proportions of black-
damp are breathed is. however, due to carbonic acid alone.

of the Extinctive
By Prof. Frank

Kebruarj' 21. — "The Composition
Atmospheres produced by Flames.
Clowes.

In a former paper {Roy. Soc. Proc, vol. Ivi. ), the author
communicaied the results obtained by mingling gases, which
were extinctive of flame, wiih air, until a flame burning in the
air was just extinguished. The gases used in the experiments
were carbon dioxide and nitiogen. Eaih of these gases was
separately introduced into the air, and ihe com) osiiion of the
atmosphere thus produced, which just extinguished flame, was
determined by chemical analysis.

The general results arrived at were : —

(1) J hat wick-fed flames require atmospheres of very similar
composition to extinguish them : while gas fed flames require
atmospheres of widely diflering composition.

(2) That nitrogen must be added in larger proportion than
carbon dioxide, in order to extinguish the same flame.

{3) That the minimum proportion of extinctive gas which
must be mingled with air in order to extinguish a flame is
independent of the size of the flame.

A sup, lementary series of experiments has now been under-
taken in order to determine the composition of the atmosphere
exiinctive of each flame, which is produced by the flame itself
when burning in an enclosed volume of air at atmospheric
pressure. The apparatus used and the method of experimenting
are fully de«crihed.

As in ihe previous series of experiments (/i)^. crV.) the com-
bustible substances used were chiefly those which are burnt fur
ordinary healing and lighting purposes — namely, alcohol (abso-
lute), alcohol (methylated), paraffin (Limp oil), colza and
par'.-ffin, candle, hydrogen, carbon monoxide, methane, and
coal-gas.

Determinations were made of the percentage composition of
the rC'idual atmospheres Itft by the flames, and these were
compared with the composition of the ariilicial atmosphere in
which tl.ime is just exiingui-hcd, and with the composition of
atmospheres which are resi>irable according to the recent ex-
pcrimenii of Dr. Haltane (Proc. Roy. Soc.'\.

The conclusions draun from the tabulated results of the
experiments pulilished in the paper are that : —

(1) The flames of the comhu^iiblc gases and liquids, which
were experimented upon, produce, at ihe poml ol extinction in
an encloned atmosphere, a change in the proportion of oxygen
in the air generally corresponding to that produced by prepar-
ing extinctive atmospheres by artificial mixture.

(2) The flames ol candles and lamps, when they are extin-
guished by tiurning in a confine I space of air, produce an
atm'opl'Cre of almost identical composition with that of air
expired from the lungs.

(3) 1 he extinctive atmospheres produced by the combustion
of the flames of candles and of lamp^, and the air expired from
the lungs alter inspiring Ircsh air, are respirable with s.ifety.

(4) The extinction of an ordinary candle or lamp flame is
not ntces'aiily indica<lve of the un>uilabiliiy of an atmosphere
to mam am life when it is breathed.

Oeological Society, February 6 — Dr. Henry Woolward,
F.k.S, P'tiidcnl, in Ihe chair. — On tones of a Sanroirodous
Dinosaur fiom .Madagisca', by K. Lydekker, F R S. Tnc lpon-s
dc-crdied in ihr paper were c .licit-: I by Mr. Lati to the east of
the tD«n 'f Naiiinda,on the noith-^astcrn cail of Madagascir.
Thf y inc ude verl-brac, limb-l>one-, and porti'ms of pectoral and
peUic grdies. These bones were descrilic I in detail, and the
animal which possessid thtm was referred to the genus ^i?MriV>-

NO, 1324, VOL. 51]

i/ff»fl[>'/««, Owen ; a dorsal vertebra, described in the paper,
being isken as the type of the new species. The identification
of the Malagasy reptile with a type occumng in the Jurassic
rocks of England haimonises with the reference of some of the
strata of the island to the Jura-sic period. — On the physical
conditions of the Meditrrranean basin which have resulted in a
community of some species of freshwater f.^hes in the Nile
and the Jordan w.-iters, by Prof E. Hull, F. R S. The author
summaiised the evidence in favour of the existence of b,irriers
in post-Mioccnc times, separating ihe Mediterranean area intoa
chain of basins. He brought forward arguments in support of
his contention that the waters of the eastern (Levantine) basin
became fresh during a period when the area of tv«pora'ion was
smaller, and the supply of river-water greater, than at present.
Into this freshwaier lale the waters of the Nile would flow
directly. He had elsewhere given reasons for believing that the
Jordan Valley from Lake Huleh to Arahah was the bed of a Lake
over 200 miles long, and at least 1300 feet above the present
level of the Dead Sea. He suggested that Ihe waters of this
lake escaped into the Levantine basin through the plain of
Esdraelon. With such physical conditions existing, the fauna
of the Levantine basin would have had a mears of spreading
throughout the whole system of waterways connected with it.
In conclusion the author added some observations on the changes
which occuired in the Mediterranean area subsequent to the
post-M ocene epoch of tarihmovement. — On the loess and
other superficial deposits of Shantung (Nonhern China), by S.
B. J. Skerichly and T. W. Kingsmill The following
deposits were described in the order of their antiquity: — (1)
Recent fluviatile deposits. (2) Marine sands with Cardium,
Ostraa, an I Bulla, extending to a height of 20D feet above
sea 1' vel, and indicating former submergence to that amount.
(3) Old river grjvels, often resting on iorss, and possibly con-
tcmpoianeous wiih the marine- gravels. They furnish pan of the
evidence relied on by the authors for supposing the existence at
ihat time of a climate moisture than the present one. (4) Loess.
(5) Basement-gravels having the same iclanon to the loess that
the Upper Gieensand beats to the Chalk. The loess east of the
Pamirs is extensively developed over an area ol over one million
square miles. It is .sometimes over 2000 feet thick, and occurs
up to several thousand feel above sea. level. Evidence was
brought forward by the authors with the intention of establishing
the absolute want of connection between the Chinese loess and
the prtsmt rivtr-systtms, its original stratified condition (as
shown by variation of tint and horizonlality of layers of concre-
tions), and its subsequent teariangement to a great extent. The
absence of marine shells was discussed, and the suggestion
thrown out that the shells had been destroyed by percolating
water. The auihors gave their reasons f<ir supj osing that the
loess is a maiine formation, and stattd that the sea need not
have reached to a hi>;hei levtl than 600 feet abi ve 'he present
sea-level, lor the Pamir ri-g on where it .ccurs, 7000 feet above
the sea, is an aiea of special uplift. They maintained ihat there
are no proofs of the glaciatnm of Northern and Eastern Asi»,
so that Chinese loess could have no conneciion with an area
of glaciaiion. They staled that the zoological, ethnological,
hitorical, and traditi nary evi ence alike pointed to the former
depresssiiin of Asia beneath the sea, and the subsequent
desiccation of the land, consequent upon re-elevation.

Mathematical Society, February 14. — Mr. A. H. Kempe,
F.R.S., Vice-President, in the chair. — Tne chiirman announced
the decease, since the January mreiing, of Prof. Ca\ley, F. R. S.,
and SirJ. Cockle, F K.S , and slated that the Society had been
rcpre enied at the funeral of the former by the Picsidrnt, him-
sell, and Prols. Elliott, F.R.S., and Ihnnci, K.U.S. Messrs.
Walker, F.R.S., Glai-her, F.K.S,, and Elliott, F.R.S., paid
tribues to the memory of the deceased gentlemen, and a
resolution was pa-sed unanimou ly that the I'residcit (Major
Macniahon, F. R.S., who was absent owing to a rlomeslic
afiliction) be p quested to convey, in such loim as hcshouhl think
fit, voie-ol condidcnce from 'he Society to M.s. Cajlct and Lady
Cockle. — Dr. llobson, F. R.S., gave a biirfsktch ol a paper,
by Mr. II. M. Macdonilil, on ihe electnfi. ati.m of a circular
disc in any hi Id cd fmce symmetrical wiih rcs| ect to is plane.
— Prof. Elliotl reail a paper on certain niflertnt al operators,
and their use to loim a lomplete system ol seiniiivariants of
any degree, or any »ei(.h'. — I'rol. W. Huinside, F. K.S., sent
notes on the ihc< ry 1 f (.roups of finite order, lii an 1 iv. Ilerr
Iliildir, in a paper in the Math. Ann. vi.l xl., and Dr. Cole, in
a paper in the American Journal of Malhtmalia, vol. xv., have

March 14, 1895]

NA 1 URE

479

determined all the simple groups whose orders do not exceed
660. The only other kniwn results in connection with the
question as to whether there is a simple group corresponding to
a given onler are as follows. There is no simple group who se
order is the power of a prime, or whose order contains two or
three pri ue facto's ; and the only simple group who^e order
contains four prime factor-^ is a group nf order 60. The lai ter
result was established in a paper pablishei in vol. xxv. of the
Proceedings ai Wis Mathematical Society. The present paper
aims at an exti-nsion of these results. If /j, /.,. . . . /,. are
distinct primes in ascending order, it is shown that in a group
ijf order

the number of operations whose orders are divisible by /, and
by no lower prime is

(/.-i)/, + i • ■ ./..-lA.'",

from which it follows at once that a group whose order is of this
form can nei her be simple nor contain a simple subgroup.' It
is also shown that a group whose order is of the form

A'A ■ • • A -]/""■

cannot be simple, and cannot contain a simple sub-group, with
the exception of the ca>e in which it con'ains a tetrahe.ir,al sub-
group ; in which cas- /j = 2,f„- 3. Thirdly, it is shown, with
certain limitations, that if no prime entering in the order of a
group, except the greatest, appears to a higher power than the
second, the group cannot be simple. Fourthly, it is proved
that no groups whose orders are of the forms.

can be simple. A deduction from these results of general form ,
aided by the con-ilerati )n of certain more pariicu'ar cases, is
that the only simple groups whose order is the product of fiv e
I primes are the kno«vn simple groups of orders 16S, 660, an d
1092. Finally, it is shown that if in a group of order

/riA^s • • ■ A-i "« 1 ;*.."•»

the subgroups of order

Pi u Fi i' • ■ • F"-\ I'-i

are all cyclical, the group cannot be simple, and cannot contain
a simple subgroup.

Entomological Society, February 20. — Prof. Raphael
Meldola, F.k.S., President, in the chair. — Mr. W. M. Christy
exhibited specimens of Lyatna a«estis, caught in Sussex, last
summer, which had a white edgmg round the black discoidal
spot. lie said the specimens miijht, perhaps, be identical with
the northern form of the species known as the variety sa/maiis.
— Mr. H. Go^s exhibited a small collection of Lepidoptera fron
the South of France, male by Mr. Frank Hromilow. — Prof.
Meldola invited discussion upon the address delivered by Mr.
Elwes, as retiring president, on the " Geographical Distribution
of Butterflies," at the last annual meeting. lie remarked that
he had not himself had time to consider the paiter in an
adequate iiianner, but he thought that the discussion might lead
to a useful expression of opinion if ihespeakcrs would deal with
the question as to how far the scheme of distribution advocated
by Mr. Elwes w.as borne out by a comparis n with other orders
of insects. He was of opinion that in considering schemes of
geographical His ribution, the results arrived at were likely to
be of greater value the wirier the basis on which they rested,
and he therefore suggested that the ques ion might also be taken
into consideration as to how far it was justifiatile to draw con-
clusions from the consideration of one rlivision or one order
only. Dr. .Sharp, F R.S., remaiked that g-^ographical dis-
tribution consisted of two divi ions ; firstly, the facts ; secondly,
the generalisations and deductions that may be drawn from
them. He thought that as regards insects generally our know
ledge of the (acts was not yet sufficient to warrant many
generalisation*;. Siill the impressions of those who have paid
attention to particular groups of insects are even now of some
imporiance, though at present based on incomplete knowledge.
He thought the Khopalocera would prove to be a some*hat

t It has been pointed out to the auihor since the paper was communi-
cated to the Society, thai this first result is contained in a paper by Herr
G. Frob:nius, Beriincr Sitzunssbeiicltte, r8()3.

NO. 1324, VOL, 51 I

exceptional group in their distribution. Notwithstanding that
Australia and New Zealand are so poor in them, this was by no
means the case with their Coleoptera, .\ustralia being very rich,
and its fauna of Coleoptera being very distinct. He thought
that if Lepidoptera generally were well collected in Australia
and New Zealand, it would be found that this order was not so
poor in species as was supposed. He instanced the case of the
Sandwich Islands, where it was supposed that there were very
few species of Lepidoptera, and yet some 500 species, or per-
haps more, had been recently found there by Mr. R. C. L.
Perkins, who had been sent to investigate the islarids by a
committee appointed by the Royal Society and British As-
sociation.— Mr. McLachlan, F.R.S.,said he was of opinion
that no definite demarcation of regions existed, but that all the
regions over-lapped ; in any case the retention of Pal.earctic
and Naearctic as separate provinces was not warranted on Ento-
mological data. He believed that atthe closeof theGlacial period
some insects instead of going north were dispersed southwards,
and that the present geographical distribution of some forms
might thus be accounted for. The discussion was continued by
Mr. Osbert Salvin, F.R.S., Mr. J. J. Walker, Herr Jacoby,
Mr. Champion, Mr. Elwes, and Prof. Meldola. — The Rev.
T. A. Marshall contributed a paper entitled "A Monograph of
British Braconidie, Part vi."— Mr. J. W. Tutt read a paper
entitled "An attempt to correlate the various systems of
Classification of the Lepidoptera recently proposed by various
authors." In this paper he criticised the opinions recently
expressed by Mr. G. F. Hampson.and Dr. T. A. Chapman, in
certain papers published by them. .\ discussion ensued, in
which Mr. Elwes, Prof. Meldola, and Mr. Tutt took part.

Zoological Society, February 19.— Sir W. H. Flower,
K.C.B., F.R.S., President in the chair.— Mr. F. E Beddard,
F.R.S., read a paper in which he gave a description of the
brain of the Glutton {Gulo lusais). — .\ second paper by Mr.
Beddard contained a description of the brain of different
species of Lemurs that have died in the Society's Gardens,
pointing out the range of variation to be observed in the
cerebral convolutions of this order. —A communication was
read from Mr. C. Davies Sherborn and Dr. F. A. Jentink, in
which was given the dates of the publication of the parts of
Siebold's "Fauna Japonica" and Giebel's "Allgemeine
Zoologie " (first edition). — A communication was read from
Dr. J. de Bedriaga, "On the Pyrenean Newt, ^fJlge as f era,
Duges," dealing with the external, osteological, and larval
characters of this imperfectly-known Batrachian, and giving an
account of its habits.

Linnean Society, February 21. — Mr. C. B. Clarke, F.R.S.,
President, in the chair.— Mr. J. H. Vanstone exhibited
specimens of some nearly allied Hydrozoa, namely, Bcugain-
vellca r.imosa and B. musca, and after demonstrating their
structure, gave reasons for conclu'iing that although the latter
had been described as distinct by Prof, .\llman, the characters
relied upon were not of specific value but simply varieial. —
Mr. George Brebner exhiiiited some lantern slides of Glct-osi-
phoma capillaris aT\A oyhej Algae, viith accompanying descrip-
tions, anil gave an intereting account of his method of pre-
paring slides in colours.— On bthalf of Mr. J. Boerlage, the
President demonstrated the chief points in a paper communi-
cated by him on the identification of Chiovanlhiis Glusri, an
(ib-cure speces figured by Gieriner at the end of the last
century in his famous work " De (ructibus et seminibus Plan-
tarum," but hiiherto undetermined. From the researches of
Mr. B 'erlage it now appeared that it was evidently referable to
Seh podcndron costatiim, Kurz. This was made clear by the
excellent drawings which accompanied the paper, as well as by
ihe specimens which were exhibited. — .K paper was then read
by Mr. E. M. Hulmi s, on new marine Alga; from Japan. The
author pointed out that up to the pestnt time the known
sprcies of Algje from th.at country did not excee 1 300, or about
half ihe number found in Great Britain; but that the districts
around ihree centres only had been explored, namely Hakodadi,
Tokio, and Nagasaki, not« ithstanding the fact that seaweeds
are largely used as food by the Japanese, and form an iuipoitanl
article of commerce. The paper included descriptions of
twenty-three new species (the structure of which was shown by
means of the oxyhydrogen lantern) belonging to the genera
Ctadophora, Coaium, Diclyota, Diclyopleris, Polyzonias,
Chondrus, Gracitaria, Gratcloupia, Gymnogongrus, Halymeria,
Lethetshedtia, and Padina,

4 So

NA TURE

[M/.RCH 14, 1895

Cambridge.

Philosophical Society, February 25.— Mr. R. T.
CUiebiook, Treasurer, in the chair. — On binocular colour
niixlurcs, by Dr. W. II. R. Rivers. Two methnris of
producing binocular colour mixture were shown — by Wheat-
s!one's stereoscope and by a modification of Hering's
roe' hod devised by Mr. E. T. Dixon. Colour mixture
and rivalry were described as occurring in the after-imige
following binocular combination of coloured patches. — On a
new parasite probably allied to Echinorhynchu'. by Mr. A. E.
.Shipley. The specimens described came from the skin of a
bird Htmignathus frccerui, taken by Mr. Perkins in the Island
of Kauai, one of the Sandwich I.-lands. — Notes on l'.nchytheca
(with exhibition of specimens^ by Mr. A. C. Seward. The
genus Pachylhfca from Siluri.in and Devonian rocks of Britain
and Canada has been a subject of discussion among palzeon-
tologisis ever since its discovery in 1S53. Several writers have
placed the fossil among -A^lga;, and this position has been assigned
to it on the grounds of a .supposed resemblance of its histo-
logical structures to that of certain recent genera. An examin-
ation of a series of micro'icopic sections prepared by Mr.
Storiie, of Cardiff, has led the author to doubt the sufficiency
of the evidence on which the comparison with any existing alga
has been based, and to regard Pathytheca as an organism of
uncertain position which might well receive attention at the
hands of zoologis's.

Paris.

Academy of Sciences, March 4. — M. Marey in the
chair. — The life and works of Admiral Paris, member of ilie
Geography and Navigation Section, by M. E. Guyou. — Axoids
of two plane lines, by M. H. Resal. ^Prophylactic remedy for
marsh-fevers, by M. d'Abbadie. The use of a daily fumigation
of the body with sulp*-ur is urced as a preservative against inter-
mittent fevers in malarial districts. — On the interior pressure
and the virial of the interior forces in fluids, by M. E. H.
Amagat. A mathematical paper in which the variations of
certain theoretical constants, deduced from the results of the
experimental determinations of the properties of gases under
high pressures, are discussed. — Observation of Wolf's planet
BP, made at Toulouse Observatory, by M. F. Rossard. —
Rectitica'ion of some arithmetical theorems, by P. Pepin. — The
month of February, 1S95, at Pare de Saint-Maur O'lservaiory,
by M. E. Renou. A discussion of the meteorological conditions
obtaining in the neighbourhood of Paris. It is shown that
a continued low temperature is very rare in February. The
mean temperature of the month is given at - 4 '^S. The
minimum temperature was reached on the 7ih at Pare de Saint-
Maur — I5'''4, and at CI ateaudun - I4°'6, and on the gih at
Vcndome —19° 4. At the first-named station the earth w.as
frozen beneath turf to a depth of 0'53 metres, ami in the
kitchcngardt-n to a depth of 0*65 metres. — Panoramic views
obtained wiih the repeating twin-camera, liy M. J. Carpcntier.

— Ba^ic and acid oxides and sulphides. Zinc sulphide, by M.
A. Villiers. — Calorimelric researches on dilute s>luiions.
Sodium acetate, by M. E. Monnet. The heat of solution of
sodium acetate augments wi'h the concentration of the solution.

- -On hexamelhylene-amine ; ammonium salts ; action of acids ;
production of primary amines, by M. Dclei'ine. The reaction
of acids on the ammonium iodides of hixamethylene-amine.
C.II„N4RI-l-6H,0 = 6ClI,q-^3Nir, + NKM3l. is given as
a new method of forming primary amines. The use of bis-
muth potassium iodide for the isolation of these primary amines
is noted. —On the composition of French and foreign oats of
the 1893 crop, by M. Ualland. — New cin'ideralions on the
comparative anatomy of the limbs, by M. J. P. Durand (ile
Gro»). M. Edmond Perrier followed up this paper with a dis-
cu.'tion of the theory of the compound nature of the higher
animal organisms. — On a disease of the spiny lobster, by
MM. E. L. Uouvier and Georges Roche. — On the formation of
the shell of molluscs, by M. Moynicr de Villepoix. — On the
diffusion of perfumes, by M. Jacques Passy. — Researches on the
f,.,! I ,„ , "^^irriaU required liy the vine, by M. .\. Miiniz. The
f rclusions have been arrived at : (1) In all vineries
til n of nitrogen and potash is much more considera'ile
than that of phosphoric acid. (2) Nitrogen is absorbed in large
quanii y by the viite, and, contrary to widely received opinions,
nit<rigenou« manures ought to be uiied ; ihc«c are in other re-
f|)ect« the most effective. (3) In the southern vint-yards, nitrogen
is al»ort>ed in greater proportion than potash ; in more northern

NO. 1324, VOL. 51]

regions potash is most absorbed. (4) Notwithstanding the
enormous difference in yield, the southern vine requires no
greater amount of nut'iiive materials than the vines of more
temperate clim.ites. (5) The qunntity of fertilising elements
u-ed by the vine per hectolitre of wine produced is three or four
times more considerable in the more northern districts than in
the south. — On the abnormal partitions of the fronds of ferns,
by M. Adrien Guelih.ird.

BOOKS, PAMPHLETS, and SERIALS RECEIVED

Hook*:. — Abi<_>:c de la Thcorie dcs Konctions Klliptique?: : C. Henry
(Paris, Nuny). — Mechanics— Slatic^ : k. T. Glazcbr. ok (Camhridcc Uni-
vetMiy Press).— Sicam-Powfrand Mill-Wcrk : G. W. Sutdiffc (Whittaker).
— Scientific and Technical Papers of Werner von Siemens. Vol. 2. Technical
Papers, translated (Murray). — From a New England HiMsidc : W. Potts
(Macnuilitn).- Prince Henry the Navigat->r ; C. R. Bcazley (Putnam).—
Catalocue of the llird-ol Prey, with the Number of Specimens in Norwich
Museum : I. H. Gumey (Porter). — Annuario publicado pelo Ob^ervatorio
do Rio de Ja' eiro. iSq4 (Rio de Janeiro). — A Theoretical and Practical
Treatise on the Manufacture o( Sulphuric Acid and Alkali : Dr. G. Lunge,
2nd ediii- n, Vol. 2 (tiurney and Jackson). — A Students' Text Book of
Boiany : Dr. S. H. Vine^ (Sonrensch<:in).— The Origins of Invention : Dr.
(). T. Mason (Scoti). — Die Gcsellschaftsordiiung und ihrc Natiirllchen
Grundlagen : O. Amnmn (Jena. Fischer).— Die Grundgcbiidc dcr Ebciicn
Geoniciric: Dr V. tberhard, 1 Band (Leipzig, Teubner). — Vorlesungen
aus der Analytischen Geometric der Kegclschnittc : F. Dingeldey (Leipzig,
Teiibner).— The Astrologer's Ready Heckorer: C. .T. Baiker (H.ilifax,
(bccult IJnok O-mpany). — 1"he Voyage of H. ^LS. ChalUuger. A Summary
of the Scientific Kc-ults (with Appendices), 2 Pans (Eyre and Spoliis-
woodc), — Le Climai ds la Belgique en iSg^ (Bruxelles).

Pamihlets.- Sweet Cas»av.i : H. W. Wiley (Washington). — Neudrucke
von Schrilten und K.arten fiber Metcorologie und Erdmagnetismus, No. 4
(Berlin, Asher).—Uber die Grundlagen und /.cle der Raumlchre : Dr. V.
Kberhard (Leipzig. Teubner).- A Summary of Piogrcss in Mineraloay and
Petrography in 1894 (Waierville, M" ).— Sociedad Cicntifica Aigentina.
Flores «i I nbccios : A. Galllardo 1 Buen^ s Aires). — The Basic Massive Rocks
of the Lake Superior Region: W. S. Bayley (Chicago).

Shkials. — Geographical Magazine, March (Stanford). — L'Anthropologie.
tome vi. No. i (Pans) — Bulleiin of the American Mathematical Society,
February (New York). — journal of the Chemical Society, March (Gurney
and Jackson).- Natural History of Plants, Pan xi. (Btackic), — Vcrhand-
lungen dcr K. K. geologischrn Keichsanstalt, Jahrg. 1894, No i bis 18
(Wien).— Inser I Life, vol. 7. Nos. 1-5 (Washington) — American Journal of
Science, March (New Haven). — Bulletins de la Soci6t(i d'Anthropologie de
Paris, No. 8, 1894 (Paris). — Psychological Review, March (Macnullan).

CONTENTS. PAGE

The Life of Dean Buckland 457

Our Book Shelf:—

"The Birds of Eastern Pennsylvania and New

Jersey." (With Dia^^ram.') 458

Durand and Schinz : "Cons|iectus Flora; Afrlce, ou

Enumeration des Plantes d'Afiiciue." — W. B. H. . 459
Gautier and Charpy : " Lemons de Chimie." —

J. W. R 459

Letters to the Editor: —

Variation ami .Specific Stability,— W. T. Thiselton-

Dyer, CM G.. F.R.S 459

Do Plants Assimilate Argon? — E. Blass ; Prof. W.

Ramsay, F.R.S 461

The Mcisuremcnt of Pressures in Guns. — Rev. F.

Bashforth 461

The Velocity of the Argentine Earthquake Pulsations

of October 27, 1894.— C. Davison 462

The Sociity of .Spcla;ol igy. — Mark Stirrup ... 462

Contraction of Trees caused by Cold. — J. Clayton . 462
The Harrenness of Prt Cambrian Kocks. — Dr. C.

Callaway 462

The Anilicial .Spectrum Top. — Newton and Co. . 463
Research in Education. Hy Dr. H. E. Armstrong,

F.R.S 463

Notes 468

Our Astronomical Column : —

Spec'riim ip( the flrion Nebula (71

The I'xlipse of the Moon 472

The N<iiili<n/ .■llmaiiM, 1898 472

Physical Woik o( Hermann von Helmholtz. I.

{It'ith Oiai^nim.) Hy Prot. A. W. Riicker, F.R.S. 472
Jame .Walt and Ocean Navigation, liy Dr. Francis

Elgar 475

University and Educational Intelligence 477

Scientific Serials 477

Socieiieii »nd ^cidomies 477

Books, Pampnleis, and Serials Received .... 480

1

NA TURE

48 1

THURSDAY, MARCH 21, 1895.

MODERN BACTERIOLOGY.

Lehrbuch der Bakteriologischen Untersuckung und
Diagnostik. By Dr. Ludwig Heim. Crown Svo.
Pp. 528. (Stuttgart]: Verlag von Ferdinand Enke,
1S94.)

THE writer of this volume takes care to leave us in no
doubt as to its purpose. We are told in the preface,
" Fiirden Praktiker ist dieses Buch geschrieben." Again,
" Ein Lehrer und ein Fiihrer soil dies Buch sein." Even
the unfortunate student, who, in spite of attending a
practical course on bacteriology, has failed to carry
away an adequate knowledge of his subject, is to turn
to this book for consolation, where " he may yet arrive
by its assistance at his goal, providing he follow step
by step and point by point the instructions which it
contains."

But after a careful perusal of this bulky octavo volume,
we find ourselves unable to agree with the author's
estimate of his book. It contains a mass of facts, a
bewildering maze of detail through which we think no
student would have the patience to thread his way, much
less the student who has failed in spite of passing through
a course of practical instruction. Possibly Dr. Heim knows
too much, or is too generous in giving his knowledge
away. A little more reticence would have not only made
his book less unwieldy in dimensions, but the whole
treatment of the subject would have gained in simplicity.
The excessive love of minute detail is characteristic of
most German text-books, but we do not think the follow-
ing example of it will easily be surpassed : " Smokers
must put their cigars or cigar-ends so down that the
burning part rests on the table, the mouth-piece remain-
ing free. Eating must not under any circumstances be
carried on in the laboratory. The moistening ot the
fingers in the mouth is to be rigidly avoided. Gum libels
must only be wetted with water." We can only say that
if the student approaches his subject with as little feeling
for it as the necessity of these instructions implies, he
will, we predict, never do much, however often he may
read through Dr. Heim's volume !

The work is divided into three parts — bacteriological
manipulations, including microscopic investigations; the
preparation of culture media, and experiments on animals.
The latter section is given in greater detail than in most
text-books, and is very clearly described. Secondly, the
morphological and other characteristics of bacteria, con-
taining an admirable though brief account of the subject
of immunity and the latest developments of serum thera-
peutics. Thirdly, the diagnosis of bacteria in disease, as
well as their demonstration in our surroundings. The
information imparted is, in nearly all cases, gathered from
tlje most recent publications in Germany ; but on con-
sulting the list of journals referred to in the text, the
only foreign publication considered worthy of notice is
the Annates de I'Institut Pasteur, English periodicals
being completely ignored, as well as the excellent Annali
deW Istituto d'Igiene Sperimentale, published in Rome,
and the official reports, published in St. Petersburg, of
NO. 1325, VOL. 51]

the work carried out in the Imperial Institute of Experi-
mental Medicine.

This accounts for the omission of all reference to
Palermo's most interesting experiments on the attenua-
tion of the pathogenic properties of the cholera bacillus
through exposure to sunshine. In the section describ-
ing the methods which may be adopted for reducing and
increasing the virulence of particular bacteria, mention
is made of Arloing's isolated investigation on the attenua-
tion of the disease-producing powers of the anthrax
bacillus through three hours' insolation ; but the fact is
passed over, that Palermo succeeded in reducing cholera
bacilli to the condition of vaccine through the action of
sunshine, so that guinea-pigs, when inoculated first with
insolated cholera bacilli, and then with ordinary virulent
cholera bacilli, instead of dying, as usual, in about
eighteen hours, remained alive.

The survey of the present state of our knowledge on
the question of immunity is, perhaps, the most interest-
ing and best-written portion of the book. Theoretical
considerations of the subject are kept in abeyance, and
prominence is only given to the practical outcome of
the investigations which have been made. The results
of Roux's application of serum in the treatment of diph-
theria in the Pans hospitals appeared too recently to
admit of incorporation here. In the section on the pro-
duction of spores, the author throws doubt on Roux's
method for obtaining anthrax bacilli permanently de-
prived of their power of producing spores, so-called
asporogene anthrax. He states that he has not been
able to succeed in procuring such a race of anthrax
bacilli, although he has made numerous attempts with
the utmost regard to Roux's recipe. The method de-
vised by Phisalix is preferred, which consists in pro-
longed exposure of anthrax cultures to a temperature
of from 30° to 42° C. ; but this device only answers
as long as the bacilli are kept in ordinary cul-
ture media, for even when introduced into broth con-
taining a fraction of guinea-pig's blood, they are at once
sufficiently revived to produce spores.

In describing the capacity for multiplication possessed
by bacteria, an interesting experiment is cited, which
we do not remember having seen elsewhere, showing
that 149 cholera bacilli kept at 37° C. had within three
hours increased to as many as 96,000, and that the
minimum time occupied by these bacilli in the produc-
tion of a new generation was twenty minutes. This
involves, however, the assumption that in the process of
multiplication from every individual cell two new ones
are started, never more or less.

The concluding portion of the volume, which deals
with bacteriological diagnosis, and occupies close upon
200 pages, is helpfully illustrated by photographic plates
of many pathogenic micro-organisms. In this section,
in speaking of the vexed question of the microbic origin
of scarlet fever. Dr. Heim considers that the cause of this
disease has not yet been discovered, and that the
streptococci which have been found by various observers
must be regarded as a secondary and not primary
infection ; in his own words, " man muss sich wohl hiiten
dabei die Grundkrankheit zu iibersehen." According to
Doehle, scarlet fever may be with more likelihood
ascribed to protozoa; and this authority is of opinion.

Y

482

NATURE

[March 21, 1895

that similar organisms may very possibly be found to be
the exciting cause of both measles and small-pox. In
malaria protozoa are now accepted as the origin of the
disease, and a similar suggestion has been made to
account for yellow fever in the absence of all trustworthy
microbic evidence. The examination of air, water, &c.,
for micro-organisms, is, of course, only dealt with in a
very cursory manner. In the small section devoted to
wafer-bacteriology, we are glad to find Dr. Heim calling
attention to the errors which may so easily occur in the
correct numerical estimation of bacteria in water.

Dr. Heim has spent an immense amount of patient
labour on the compilation of this volume, and he ap-
proaches his subject invariably from the point of view
of a man who has worked out things and problems for
himself; it is thus that his book acquires an original
flavour, which, whilst making it more palatable to the
teacher, renders it less likely to find favour, or prove use-
ful to the student. We venture to ih'nk that it will, in
the concluding words of the preface, "sich den Herrn
KoUegen niitzlich erweisen " ; and it must in any case be
regarded as a responsible and noteworthy contribution
to the bacteriological text-books, now fairly numerous,
already in existence. G. C. Frankland.

CHEMICAL ANALYSIS.

Die wisunsihaftlichtn Crundlagcn der analytischen
Chemie. Von \V. Ostwald. (Leipzig : Wilhelm Engel-
mann, 1S94.) _

'TT'HE Professor of Chemistry in the University of

Leipzig has taken so assiduously to the making of

books that, as repaids the fruitfulnessof his pen, he may

well take rank with even the more prolific of our writers

of fiction. Despite this fact, it is not loo much to say

that none of his productions will appeal to a larger

section of the chemical public than the little volume

under notice. For although it is professedly a work on

general analytical chemistry, it will mainly make its

mark as a concise exposition of qvalitalive ansilysis,

based upon the most recent developments of chemical

theory.

The author first deals with the modes of recognising
substances- ..^//jAjnj/j- and Vorgangscigenschafteit — and
the modes of separating substances prior to recognition.
Amongst other things the theory of filtration and wash-
ing is discussed, together with the complication intro-
duced by "adsorption"— that curious property in virtue of
which the concentration of a solution near the surface of
an immersed solid is greater than the average concen-
tration. Separation, it is emphasised, must always be
mechanical, and if it cannot be effected directly by the
physical meihods described, such as distillation or the
action of solvents, chemical operations, such as form the
subject-matter of qualitative analysis, have first to be
performed.

At this point we meet with views which are novel in an
analytical text-book. The theory of analysis, it is urged,
is now upon a new platform. Wiih van't Hoff and
Arrhenius, we must regard the properties of dilute
solutions of acids, bases, and salts as mainly those of
NO. 1325. VOL. 51I

their ions: and herein lies a simplification of the
utmost importance, for it is possible to express in terms
of the properties of, say, 50 anions and 50 cathions
the properties of the 2500 odd salts to which they may
give rise. A digest of the new theory of the constitution
of solutions is here given, and of the mode in which the
law of mass action may be extended to analytical re-
actions by regarding the ions as individual substances.

A precipitate in its mother-liquor we are to regard as
a system in equilibrium. Precipitation is never com-
plete. On precipitating BaSO,, for example, a small
amount remains in solution, and portion of this is dis-
sociated into the ions Ba and SO4. The precipitate is
in equilibrium with the soluble Ba.SO,, while it in turn
is in equilibrium with the ions. Now the active mass of
a solid is constant, hence for equilibrium the product
of the concentrations of the ions in the solution must
have a definite value — the solubility product. If the
product be r..ised above this definite value, more precipi-
tate .Tiust form ; if it be lowered, more precipitate must
dissolve. We have here a reason for the common prac-
tice of adding an excess of precipitant in order to ensure
complete precipitation. In the case quoted the solubility
product of the BaS04 will be partly kept up to the
necessary value by means of the Ba ions of the excess of
precipitant, and hence less BaSO, will require to rem^iin
in solution. This is a particular instance of the general
rule that the solubility of a substance i- diminished by
the presence of another having an ion V common with it.
We can thus formulate a theory of precipitation. It is
in general the result of interaction between ions ; conse-
quentlv, if on mixing two solutions ions are present which
can form a substance having a sufficiently small solu-
bility product, that substance is precipit.ited, and causes
which al'fect the solubility product are the causes affect-
ing the precipitation. Here are one or two instances
of this method of treating analytical reactions.

The solubility of Mg(HO)._, in water is regulated by the
solubility product of Mg and HO ions. If hydrochloric
ac.d, which is almost completely dissociated, be added
to the water, the H ions of the acid at once unite with
the HO ions of the dissolved ^'gCHO), to form water,
because water is practically undissociated. In this way
the solubility product of the Mg(I10).j is diminished, .ind
more solid Mg(H0)2 must dissolve in order to maintain
the product at the value necessary for equilibrium. If
sufficient HCl be p.esent, all the Mg(Hu)a will pass into
solution.

The following case of precipitation is more complex :—
If CO, be passed through a solution of Pb(N03^2, little or
no precipitate is obtained, whereas two-thirds of the
lead is thus removed from a solution of Pb(CjllaO.^).,. In
solution carbonic acid is but slightly dissociated into its
ions 2H and CO3 ; yet if Pb(N03)._, be present, the pro.
duct of the concentrations of the Pb and CO3 ions it
greater than the solubility product of PbCO, ; hence a
precipitate foims. At the same time, however, IlN'Oj is
produced, and H and NO, ions accumulate in the solu-
tions, since IlNOj is strongly dissociated. Now H ions
diminish the electrolytic dissociation of the H.jCO, just
as excess of NH-, or HCl diminishes the ordinary dis-
sociation of NH,C1. The solubility product of the CO
and Pb ions is thus diminished, and but a small quantity

March 21, 1895]

NATURE

48J

I

of HNO3 has to accumulate, that is, but little decom-
position has to take place, before the solubility product is
reduced to the critical value, and no more precipitate is
produced.

If Pb(C.,H30.,)_, be used, since acetic acid is but feebly
dissociated, much more precipitate can be produced
before the H ions introduced into the solution by the
acetic acid are numerous enough to reduce the solubility
product to the critical value, and thus stop further pre-
cipitation.

Reactions may also be due to the formation of com-
plex ions. Alumina in presence of water is in equili-
brium with the ions Al and 3OH. If KOH be added,
K3AIO3 is produced, of which the ions are 3K and AIO3.
The latter is not available for equilibrium with alumina,
hence the solubility-product is reduced, and more
alumina must dissolve.

With a chapter on quantitative estimations, such is the
subject-matter of the theoretical part of the book. The
second, or practical part, is concerned with the important
reactions of qualitative analysis, treated as m'lch as
possible from the above standpoints.

The book is not written for the beginner, but to supply
adequate theoretical support to the routine work of
general analytical chemistry. Enough has been said
to show that it is in great part unique, and through-
out it is refreshing and profitable reading ; indeed,
it affords the easiest means yet offered to the general
reader of getting the gist of current views, not only of
the theory of analytical processes, but of the con-
stitution of solutions, and of chemical mechanics —
the law of mass action and the velocity of chemical
change.

The ideas put forward relating to the nature of
analytical processes are, of course, open to differences of
opinion. The time has no doubt passed when the con-
ceptions of ions and electrolytic dissociation were re-
garded as but the vain imaginings of mathematicians
who had dabbled in chemistry. Nevertheless the view is
still widely spread, at any rate in this country, that
although they serve as a means of correlating otherwise
isolated properties, and of predicting phenomena in
solution, they are altogether too artificial to be anything
but the crudest picture of what actually exists. Be this
as it may, the book before us serves a good purpose,
inasmuch as it puts in a clear light the fact that the
direction of analytical reactions is determined by the
solubility of the possible products of the interaction,
and that when the reaction has run its course we have
a system in equilibrium again governed by solubility.

In the common method of presenting qualitative
analysis to the student, theoretical considerations are
either entirely ignored, or are supposed to be supplied by
statements asserting that a precipitate AB is formed in a
given solution because the affinity of A for B is greater
than its affinity for the other radicles present. It is this
system, coupled with the abuse of the ordinary chemical
equation, whereby all reactions are regarded as perfect,
that fills the ranks of budding chemists with disciples of
Bergmann,the gospel according to Berthollet, Wenzel,
and Guldberg and Waage, notwithstanding.

J. W. Rodger.

NO. 1325, VOL. 51]

ANALYTICAL GEOMETRY.

An Introductory Account of certain Modern Ideas ana
Methods in Plane Analytical Geometry. By Charlotte
Angas Scott, D.Sc, Professor of Mathematics in Bryn
Mawr College, Pennsylvania. Pp. xii. -|- 288. (London:
Macmillan and Co., 1894.)

DR. SCOTT'S treatise is a welcome addition to the
many excellent text-books on analytical geometry
which have been published during the last few years.
But while most of the text-books in use at the present
time adequately explain the initial difficulties of the sub-
ject, scarcely one can be regarded as a satisfactory book
for those students who wish to go beyond the elements
as treated with the use of Cartesian coordinates. For such
students Salmon's "Conies" is still the standard work.
But although every fresh edition of this is carefully
revised to meet modern requirements, there are many
beautiful geometrical methods and theories which are
only briefly noticed, but which should be fully discussed
in a standard work. The book under revievv does not,
indeed, aim at replacing Salmon's, but it is admirably
adapted to be used as a companion to it. It aims at
giving a concise account of the principal mo iern develop-
ments due to Cayley, Clebsch, Reye, Klein, and a few
other continental geometers. As an introduction to the
study of the higher branches, it may be confidently
recommended to students as a clear, full, and well-
arranged exposition of the leading principles of the sub-
ject. At the same time the book is sometliing more
than a text-book for students. Those who wish to keep
up their mathematics, and have no time to spare to read
the various papers and memoirs that are published
every year, will find much that will interest them — many
beautiful geometrical ideas that are here published for
the first time in an English text-book.

The author starts with the general idea of coordinates,
and develops simultaneously the theory of point-coordi- -
nates and line-coordinates, with a full explanation of
the special peculiarities of the two systems. The prin-
ciple of duality is then explained, and the descriptive
properties of curves discussed. After a short but ade-
quate chapter on curve tracing, the theory of projection
and homography is introduced, leading up to the theory
of correspondence. The chapter devoted to this theory
is very well written, and is in fact one of the principal
features of the book. In it will be found a full discus-
sion of quadric inversion, based on a memoir by Dr.
Hirst. The remaining chapters are devoted to a dis-
cussion of the generalisation of metrical properties of
curves obtained by replacing the circular points by a
conic, and a brief explanation of the connection which
subsists between geometry and the algebraical theory of
invariants.

The treatise is confined to plane geometry, in which
figures are considered as combinations of points and
straight lines. In constructing a system of coordinate
geometry for such figures, two theories naturally present
themselves ; the two in which the point and the straight
line are, respectively, the primary elements, and the
straight line and point the secondary elements. But
although Dr. Scott states that any other geometrical
entity might be taken as the primary element, she makes

4S4

NA TURE

[March 21, 1895

no allusion to any such theory. We wish that she had
found i: possible to introduce a brief notice of the
analytical theory in which the circle is taken as the
primary element in view of the fact that most of the
properties of an important class of curves— bicircular
quartics — are best discussed by expressing the equations
of these curves in terms of circular coordinates.

It is also a matter of regret that the use of trilinear
coordinates is retained, although results are usually
given in terms of areal coordinates as well. The use of
both systems is confusing to students, and the use of
the areal system has a double advantage ; firstly, the
fundamental metrical formula are more easily proved,
and secondly, the areal system is intimately connected
with the tetrahedral system in solid geometrj'. For the
latter reason, if for no other, it is very desirable that the
use of trilinear coordinates should disappear from our
text-books on plane geometry. In this book the proofs
of two fundamental results (§§ 20, 21) are long and
tedious.

The only other point we have to find fault with is that
harmonic relationship and involution are introduced as
particular cases of cross ratio and homography. The
author herself admits (p. 160) that this view disguises
the real difference between the two conceptions, and ex-
plains that while cross ratio and homography relate to
different spaces, harmonic relationship and involution
relate to pairs of elements in the same space. The
theories are developed independently, but we should
have preferred that the theory of harmonic groups and
the theory of involution should have been developed
before the introduction of the idea of cross ratio and
homography.

The examples chosen by the author to illustrate
various theorems have been very carefully selected, and
should be found quite sufficient for the use of students.
.Among them will be found many theorems of inde-
pendent importance, which could scarcely be said to come
within the scope of the book. We may add that an
excellent index is provided. R. L.

ObR BOOK SHELF.

Les Aurores Polaires. By Alfred Angot. Pp. 31S.

(Paris: Felix Alcan, 1895.)
France has made two important contributions to the
knowledge of aurorae. Perhaps the first work devoted
entirely to the study of auroral phenomena was the
" Trait'j physique et historique dc 1 aurore bor<-ale," by
Mairan, published by the Paris Academy of Sciences in
1733. A century later a volume was published containing
the results of aurora observations made on the Recherche
during the scientific expedition to Lapland. The plates
which illustrated the observations then made have been
laid under tribute by M. Angot for the present volume.
.Since the publication, however, of the "Aurores
Horcales ' which resulted from the 1S3S-39 expedition,
we have it on the authority of M. .Anj^ot that no work
dealing wholly with the subject has appeared in France.
This volume, therefore, stands as practically the only one
in which our neighbours on the other side of the Channel
can find a popular account of aurorx, written by one of
their own countrymen.

M. Angot has treated the subject lightly, yet scien-
tifically. He traces the history of aurora observations

NO. 1325. VOL. 51]

from the time of Aristotle ; describes the apparently
adventitious forms assumed by the phenomena ; explains
the facts as to the extension, position, frequency, and
periodicity of aurorae ; develops the relations between
auroral and terrestrial magnetism and electricity, and
connects them with meteorological phenomena; and,
finally, he presents the cosmical, optical, magnetic, and
electrical theories put forward to account for the pheno-
mena.

\ list is appended, giving in chronological order all
the aurora: seen in latitudes above 55' North from 1700
to 1890, with the names of the places at which obser-
vations were made. Eighteen rather coarse illustrations
are distributed through the book. Altogether, the volume
is a valuable summary of the growth of knowledge of
auroras.

A Fc-iu Chapters in As/ronomy. By Claudius Kennedy,
M.A. (London : Taylor and Francis, 1S94.)

In these 150 pages are discussed four or five of the
numerous problems in astronomy, and these are handled
in such a manner as to make them full of interest, both
for the general reader and for the student. This book,
unlike many others, is not written for the sole purpose
of pouring condensed knowledge into the student's head,
but for those who wish to sit down for half an hour or
so and read for recreation, and so gain a fair under-
standing of some of the discussions contained in them,
without going into too great detail. The points chiefly
referred to, are, visual illusion affecting certain astro-
nomical phercmena : the effect of theeaith's lotaticn on
certain moving bodies, as projectiles, paths of projectiles,
Foucault's Pendulum and the Horizontal Pendulum ; the
causes of the tides ; the moon's variation ; and the
parallactic inequality. In the last two chapters the text
is accompanied by several figures.

As a supplement to the ordinary text-books on astro-
nomy, this small volume will be found especially useful,
as it deals with subjects not generally referred to in them,
or at least only briefly mentioned.

Mechanics for Colleges and Schcols : Sialics. Bv R. T.
Glazebrook. M.A., F.R.S. Pp. 180. (Cambridge
University Press, 1895.)

This addition to the physical series of the Cambridge
Natural Science Manuals will haidly add to the
lepiitaticn of the assistant diiector of the Cavendish
Laboratory. The only noteworthy feature is the pro-
minence given to the experimental verification of statical
principles ; but excepting this, little can be found to
distinguish the book from others of a similar type.
Many oi the experiments described are intended to be
performed by the students, and the theoretical con-
sequences are, when possible, deduced frcm experi-
ments. This is undoubtedly the right line to go upon,
but we are afraid that few of our schools or colle^'es
possess at present sufficient apparatus for the laboratory
work described. The text is clear and concise, and
sufficiently illustrated ; and the examples are numerous.

The Telegraphist's Guide. By James Bell, A.I.E.E.
Pp. loi. (London : Electricity Office, 1895.)

Tei.kckaphists in the Government service have now to
submit themselves to a technical examination before they
can obtam promotion. Herein we have a guide in which
the subjects of the new examination arc considered in
the order laid down by the Postmaster-General. The
aspiring telegraphist will find the book a means of
acquiring the knowledge he needs; and students of
lelegraphy not directly cornecled wilh the service, ma;
obtam fum it useful inloriralion on the practical work
ing oftelegraphic systems.

March 21, 1895]

NATURE

485

LETTERS TO THE EDITOR.

[The Editor does not hold himself responsible for opinions ex-
pressed by his correspondents. Neither can he undertake
to return, or to correspond with the writers oj, rejected
manuscripts intended for this or any other part of Nature.
No notice is taken of anonymous communications. ]

Corrections of Maximum and Ex-Meridian Altitudes.

In navigation the error inlroiuced by taking the maximum
altitude of a heavenly body for its meridian altitude is njt
sufficiently great to need correction when it is du; to variation
of declination alone, as it is then much within the probible
errors of observation. When, however, a ship is steaming at a
high speed, the error is considerably inireased by the variation
of latitude, especially when this is of opposite sign to the varia-
tion of declination.

The formula giving the correction in seconds of arc to be
applied to the zenith distance of a body fo; red iction to the
meridian is

x = Ch- (I)

cos /cos 5 sin- 15'

where, with the usual notation C :

and

2 sin (/^S) sin l"
h is the hour angle in minutes of time. Thu;, if : be the zenith
distance, we have the equation

2 - C/;= = / q: 5,
the upper or lower sign being taken according as / and 5 are of
the same or of opposite sign. Since we may consider z, h, I,
and 5 as functions of the mean time t and C CJnitant, v.e have
on differentiation, if ; be a minimum,

dt dt ^ di

Let H and H' be the hour angles of the bjiy an I the ship's

zenith measured from som; fixed meridian, anl let k, v denjte

the northerly and westerly components of th; ship's velo;ity in

dh dH dH' ^ dl Ai -f.v, K J '

— ._j Alsoif the bady s

2Ch'^ =

knots ; then

— r- and ,

dt dt dt dt

projection on the Earth's equator moves round at the rate ot
U knots,

——/ ■— = u sec //U ;

dt / dt

and the above equation becomes

2C/i— (I - »sec//U) = z; q: 5

(2)

Now this equation will assum; different forms according as the
body under consideration is the Sun, a star, or the Moon. For,
since the motion of the ship is expressed in mean solar time, the
motion of the body must likewise be expressed in that time.

The unit o( time being a minute of mean time, and the unit
of arc a second of arc, we have for the Sun

~= I and U = 900,
dt
so that (2) becomes

- 2Ch{i — u sec //900) =: v^h.
For latitude 60° and u = 20 the value of u sec //900 is abou t
■04i so that we see for ordinary speeds and ordinary latitudes
reached the term involving u may be neglected, and the
equation reduces to

- 2C/( = z; If 5 (3)

For a star

dVl _ length of mean solar day _
dt length of sidereal day

with sufficient accuracy, and as before we obtain equation (3).
For the Moon

dH _ length of mean solar day _ I
dt length of lunar day I '035

and

U = 869,
so that in this case (2) becomes

- 2C/i = 1-035 (J'T*)-
On giving C its proper value, and putting :</ for the velocity
compounded of the velocity in latitud; of the ship anl t'le
velocity in declination of the body (3) becomes

h = ~ zw(tan / :f tan S) sin i' cosec- 15' . . (5)
NO. 1325, VOL. 51]

The reduction is therefore from (i)

X = - '—(tan / :f tan 5) sin 1 " cosec- 15' . . (6)

Equations (5) and (6) therefore give the hour angle (from the
ship's meridian) and reduction for the Sun or a star at the
maximum altitude. For the Moon I'oiyui must be substituted
for w. The form of these equations has suggested the construc-
tion of the accompanying table, which gives the value of

I

■004

21

•09S

41

•221

2

•009

22

•103

42

•229

J

•013

23

•108

43

•237

4

•017

24

■"3

44

•245

5

•022

25

■nS

45

■254

6

•026

26

•124

46

•263

7

•031

27

•129

47

■273

S

•03s

28

•135

48

•283

9

•040

29

•141

49

■293

10

•045

30

•"47

50

•303

II

•049

3"

■'53

51

■314

12

•054

32

•159

52

•326

13

■059

33

•.65

53

•338

14

•063

34

■171

54

•350

'5

•06S

35

•17S

55

•363

16

•073

36

•185

56

■377

17

•078

37

•192

57

•392

18

•083

38

•199

58

•407

19

•0S8

39

•206

59

■424

20

■093

40

•213

60

•441

tan x° sin i" cosec" 15' as far as -r = 60. Thus in latitude f
when a body (Sun or star) of declination 5° is at its maximum
altitude, the sum or difference (according as / and 5 are of
different or of the same name) of the arguments corresponding
to /and S multiplied by w gives the hour-angle in minutes of

time : the sum or difference multiplied by ~ gives the reduc-
tion in seconds of arc. For the hour angle of the Moon
the sum or difference must be multiplied by i '035tf, and for the
reduction by i(f035w)-.

Example. — D.R. latitude 48^ N. Moon's declinaaon iS' 48'
S. decreasing 120 per lom., ship steaming S. 20° E. 16 knots.

Remembering that when the ship is in N. latitude, and
steaming towards south

w = - z; :p 5,
we have

and

w = - 27,

/« = 27 X i'035(-283 -1- -087) = io-3m
X = 144"

If a ship whose maximum speed is 20 knots does njt reach a
higher latitude than 60, the greatest values that /; and .v can
have, are for the Sun, 9m. 15;. and l' 37 ; for the Mjon,
17m. 20;. and 5' 41 ".

I will now investigate the nature of a diagram ' from which
the reduction in ordinary ex-meridian observations may be
obtained, as well as the hour angle and reduc'-ion for o'.aximum
altitudes. It is found convenient for this purpose to express x
in minutes of arc, when (i) becomes

/(- = 2-v(tan / If tan 5) sin i' cosec -15' ... (7)

Now if a circle of radius a be referred to a point in its cir-
cumference as origin, its equation is
r^ = 2ax,
r being the radius vector and x the abscissa measured along the
diameter through the origin. Comparing this with (7) we see
that if asystem of circles bedescribid pissing through a common
origin o, their centres being collinear and on the same side of
o, the reduction > is the abscissa of the point whose radius
vector is /; on one of these circles: the particular circle on
which the point lies being that whose radius is the sum or
difference of the ordinates of the curve

corresponding to

y = tan x sin I ' cosec- 1 5
.V = / and X = d.

1 A diagram based on the properties of the parab jla wa? given by ProC
Foscolo, of Venice, and publtahed by the Hydr^graphic OfSct about 1870.

4S6

NATURE

[March 21, 1895

It will be ncticedihit when

i5>2(tan / ± tan S) sin i' cosec- ij',
the aboTe corsf uction fails, and .r may be then considered as
twice the abscissa of the point on the circle whose radius is
2{tan / T tan S) sin i' cosec" 15',

By making a diagram on ruled paper, the distance between
the lines being taken as unit, the diBBcully of measuring x and k
is more or less overcome.

A portion of such a diagram is represented in the annexed
6gure, c D being a portion of the curve

V = tan -T sin i' cosec- 15'
described with c as origin, y being for convenience reckon ed
negatively

As an example of its use. suppose it were required to find
the reduction for latitude 17' N., declination 9° S., and hour-
angle I2m. By using a pair of dividers the sum of the ordi-
nates of the curve c D corresponding to 9 and 17 is found to be

7, and a radius vector of length 12 meets the circle of radius 7
at a point whose abscissa is 10. The required reduction is
therefore 10'.

Again, i being now expressed in minutes of arc (5) and (6)
may be written

h — - ^(tan / T tan 8) sin 1' cosec- 15'
60

©■"

an /T tan 8) sin i' cosec- 15'.

So that h and i are the lengths of the arcs of a circle and its
involute respectively, corresponding to the angle at the centre
who5e circular measure is -jujfxt in the case of the Sun, and
I 035^", 60 in the case of the Moon. Now for the former body
T'will not in general exceed 20, and for the latter 38, so that
we may assume for graphical purposes that in the case of the
Sun tu is the number of degrees in an angle of circular measure
?i»/6o, and in ihe case of the Moon iv it the number of degrees
in an angle of circular measure I '035zi//6o.

Thus in both cases h is approximately the arc of a circle of
radius

(Ian /^lan 8) sin I'cosec" 15'
intercepted between the diameter and the radios which makes
an angle w degrees with it.

Having obtained h, x may he found as in the general case, or
by drawing a tangent to meet the involute, as in the figure.

In the preceding example, suppose the .ship to be steaming
south 20 knots, the ileclination decreasing 160' per lom. Here
» 5B - 36- By laying off at an angle of 36°, the intercepted

NO. 1325. VOL. 51]

arc bd is found to be about 43, and by drawing the tangent at
* the intercepted arc of the involute is about I •3. The hour
angle and reduction for the maximum altitude are therefore
4m. -3 and i''3 respectively.

The graphical method considered above will be found to
give results which, although approximate, are sufficiently
accurate for purposes of navigation ; in fact, il Ihe diagram
be constructed on a large scale, the reduction may be easily
obtained within fifteen seconds of the truth.

H.M.S. Ha-j/ke, Mediterranean. J. White.

Table of Elements.

IN OROtH OP ATOMIC W»GMT^.

20"

c/

V

W

Argon and the Periodic Systenu.

The annexed engraving is a copy, on a small .scale, of a large
diagram which I have used with advantage for some years in
dealing with Ihe periodic classi-
fication of the elements. It
may prove of some little interest
to your readers who are actively
discussing the probable position
of "argon," on the assumption
that this remarkable substance
is an element.

To the left of the illustration
is a scale of equal parts, and
the dots indicate the atomic
weights of Ihe elements the sym-
bols of which are placed farther
to Ihe right. The latter are ar-
ranged in zig zag fashion so as
to exhibit the periodic rise and
fall in gercral properties, ob-
served in each set of seven
elements. A certain analogy
may be traced between these
periods and the loops into
which a suspended cord of
somewhat unequal weight can
be thrown when set in vibra-
tion. Each small loop pictures
for us a small period ; and, just
as Ihe alternate loops are those
which are in the same phase at
any given moment, so the alter-
nate periods of Ihe elements are
those between which Ihe closest
resemblances can be traced.

The members of Mendeleef's
eighth group, or the " triplets,"
as they are sometimes called,
viz. Fe, Ni, and Co, with atomic
weights from 56 to 59 : ku, Rh
and Pd, 102 to 106 : Os, Irand
I't, 191 to 195, seem to form
another system of elements
which — to pursue the analogy of
the vibr.iting cord — is related to
that of the other elements some-
what as a given note to its
octave. On carrying the eye
along Ihe curves it will be seen
that Ihe atomic weights of trip-
lets occur nearly opposite to the
points of maximum displacement
of three of the greater loops.
We know very little as yet about
the elements Ihe atomic weights
of which lie between 140 and
180, hence we cannot recognise
the triplets Ihe .atomic weights
of which should be near to 150;
and a similar remark applies to
the elements above 210. But
the distribution of the triplets
throughout Ihe whole of Ihe best-
known elements is so nearly
regular that it is diflicult to avoid
Ihe inference that Mrc/- elements

should also be found in the symmetrical position between 19
and 23, i.e. between fluorine and sodium. And further, that

'^'

??

Tl.

March 21, 1895]

NATURE

487

these elements — of which "argon" may be one — should exhibit
propertiesdiflferiDgchiefly in degree from the alternate palladiuai
and platinum triplets ; while hydrogen would appear as the
primarj- of both systems of elements.

Dr. Gladstone's letter, which appeared in your issue of
February 21, admirably puts the reasons for preferring an
atomic weight of about 20 for argon to the higher number
which Lord Rayleigh and Prof. Ramsay are now disposed to
assign to it ; but Dr. Gladstone seemsto think that there is room
for only one element, whereas three are possible, as I pointed
out at the Oxford meeting, for the reasons given in the foregoing.

It will be seen from the illustration that an element with an
atomic weight between 36 and 39 would belong to a third
system of elements. But the sole ground for concluding that
the atomic weight of argon lies between thcie points, is the
ratio of the specific heats as determined by Kundt and Warburg's
method. Lord Rayleigh and Prof. Ramsay found this ratio to
be nearly equal to that afforded by mercury gas, the molecule of
which is monatomic and density only half its atomic weight; hence
they conclude that the argon molecule is monatomie, and that
its density of nearly 20 represents but half the atomic weight.
Now, while any opinion on this point, coming from the dis-
tinguished discoverers of argon, is of the highest value, it seems
possible to attach undue weight to the very slender evidence
afforded by the specific heats, for mercury at present is the only
one of the known cases of monatomie elementarj' molecules in
which the ratio of the specific heats has been determined. But,
even admitting that the energy of the mercury and t'.ie argon
molecules is chiefly translational, it is still conceivable thit the
.irgon molecule includes two atomic vortices so closely inter-
linked as to have a common centre, and therefore to enable the
molecule to simulate a monatomie character. Such a structure
would lie consistent with great stability and, consequently, with
exceptional chemical indifference. J. Emerson Reynolds.

Trinity College, Dublin, March 19.

Variation in Caltha palustris.

Reading the notice of Mr. Burkill's paper on " Variations
in Stamens and Carpels," in Nature of February 7 (p. 359),
I remembered the following notes on Caltha paluitris, which
my wife and I made at Corfe, Dorset, June II, 1891.

C. paluitris: heads in pairs on a "dichotomously branching
stalk ; number of follicles in each head, counted in several
specimens, as follows : —

7 follicles on one, 4 on the other, of a pair. 8 — 5> S — 7>
S— 6, 6—6, 6—7, 7—5, 9—9, 10—8, n— S, 9—6.

Thus there is gieat variation. One stalk is longer than the
other, of a pair, and it is presumed that in every case the
shorter one flowers first. It will be noticed that in the above
eleven instances, only two had the same number offolbcles on
both stalks. Of the remaining nine, three had most follicles
on the longer of the stalks, and six had most on the shorter.
Those on the shorter stalk werelai^er than those on the longer,
presumably because older.

A second memorandum gives the results of fifteen more
counts, all taken at random, thus ^L. = longer, S. = shorter
stalk) :—

. with most follicles.

L. and S. equal.

S. with most follicles

L. S.

L. S.

L. S.

5-4

8— 8

... 4- 6
4-8

9-8

s- S

6-7

9—7

10 — 10

8—10

7— 7

9 — 10

10—10

7- 8

4- S

It accordingly appears that the later-flowering, longer-stalked
head produced more follicles in just half the number of cases
counted (13 out of 26), and the shoiter-stalked head had a
majority in only 5 cases, the remainder being equal.
< In a Bidots found at Barbadoes (West Indies), on July 6 of
the same year, there were similarly two heads, a long-stalked
and a short-stalked, the latter flowering first. It would be in-
teresting to get statistics of the numbers of akenes in the heads
in this. The species was not certainly determined, but it is of
the section of A', bipinnata. T. D. A. CocKERELL.

New Mexico (U.S.-V.), February 24.

NO. 1325, VOL. 51]

DR. M. FOSTER ON THE TEACHING OF
PHYSIOLOGY IN SCHOOLS}

THE teaching of science in schools has, it seems to
me, two uses. The first is what I may call the
" awakening " use. Many minds who feel no interest in
the ordinary subjects of school learning, to whom the
ordinary lessons appear as so much dull mechanical
work, are at once stirred to intellectual activity when the
teaching of this or of that science is presented to them.
The second use is the more distinctly " educational,"
training use.

The minds of the young being, happily, differently
constituted, one mind is especially " awakened " by one
branch of knowledge, another by another. One boy or
girl dates the beginning of his or her intellectual activity
from the day on which he or she had a first lesson in
chemistry. Another starts in the same way with botany.
And the number of those to whom physiology thus serves
as " awakening " knowledge, is, it seems to me, sufficiently
great to render it desirable, by the introduction of the
teaching of physiology into schools, to afford adequate
opportunities for its exercising this benefical effect.

It follows that, taught from this point of view, phy-
siology should be taught as a new independent subject,
not demanding any previous knowledge ; it should be
presented as a wholly new field into which the natural
mind may wander at will without any restrictions as to
being qualified for entrance. It also follows that the
teaching must be of a most elementary kind, that as
much of chemistr)' or physics as is necessary for the
comprehension of the physiological matters should be
taught with the physiology, and, as it were, as a part of
it, the pupil being led into chemistry and physics by his
interest in physiology, and not being compelled to learn
the one for which he or she perhaps does not, at present
at least, care before beginning the other.

The instruction given, however elementary it may be,
should consist in part of demonstrations and practical
exercises. I need not enumerate these in detail, but
they must necessarily be limited in scope ; the dissec-
tion of a rabbit or some other animal to show structure,
some little microscopic work, such as the microscopic
study of the blood and of a few tissues, the examination
of the structure and working of the heart, the mechanics
and elementary chemistry of breathing, and the like.
But all these demonstrations, like the rest of the teach-
ing, I may repeat, should teach so much of chemistry,
of mechanics, &c., as is needed, as a part of the
physiological lesson.

As an "awakening" study, I am in favour of physi-
ology being very widely taught ; but, as almost neces-
sarily follows from the view on which I have been
dwelling, it ought not to be made a compulsory study.
Made compulsory, it would as an awakening study lose
much of its virtues. I do not hide from myself the fact
that the present gross ignorance which prevails among
most men and women as to the most elementary facts
concerning their own bodies is most undesirable, espe-
cially perhaps as regards women ; but I am most de-
cidedly of opinion that it is better to meet this evil by
encouraging the study of physiology than by making it
compulsory.

Physiology, as a distinctly educational study, as a
training for the mind, is a very different matter ; and it
is, in my opinion, in this aspect unsuitable for schools.
The training for the mind which physiology affords is
one, I venture to think, of no small value, but is one

t A short time .igo, on my consulting him on behalf of a committee
appointed by the Hcidmasters" Association, to draft nrgulations for major
scholarships' cxarainations, Prof. MichaeC Foster was good eno.ugb to give
me this statement of his opinion on the teaching of physiology ia schools —
.-V >ubject of great importance, but of great difficulty, regarding which much
misconception prevails : it appears to me to be so valuable, that I have
sought for and obtained his permission to publish it.— Hesrv E. Arm-
strong.

488

NATURE

[March 21, 1895

■which, especially compared with that afforded by some
other sciences, is relatively slight when the knowledge
is elementan.'. increasing rapidly as the study becomes
advanced. Further, while I have just urged that
elementar>- physiology as an awakening study may be
and indeed should be taught by itself, independent of
other kinds of knowledge, I can now urge equally
strongly that a study of physiology, beyond the mere
elements, is impossible without a previous adequate
knowledge of chemistry and physics. -Again, while the
practical teaching of the rudiments of physiology can be
carried out anywhere and by any one, the further study
of physiolog)' demands no inconsiderable laboratory
accommodation, complicated apparatus, and experiments
on animals. Lastly, if the study of physiology is to be
real, the whole body must be dealt with, no parts being
excluded for special reasons : and this means that the real
study cannot be taken up until after puberty. For these
reasons it seemstobe undesirable to press the introduction
of physiology into schools as an educational subject ; all
the more so, since not only both chemistry and physics
are admirably adapted for this purpose, but also a not
inconsiderable knowledge of both these sciences is needed
for the proper study of physiology ; and I imagine that
by the time a boy or girl is thus prepared to study
physiolog)', it is time that he or she should leave school.
While 1 am thus opposed to physiology being placed
in a false position in the school curriculum, I feel myself
all the more free to urge the very general introduction of
an elementary study of the subject on account of its
awakening value. I cannot define the amount of phy-
siology which should thus be introduced more closely
than by saying that the ground covered should be about
that covered by my Primer. I would add that so far as
is possible the pupils should sec for themselves ever>'-
thing which is talked about in the lesson.

As to " physiology- being a proper subject to be in-
cluded among subjects for scholarship examinations for
young pupils, ' I am so impressed with the painful evils
of the present scholarship system, that I am most loth
to say anything that would in any way lead to an addition
to that system. If the scholarship examination is to be
a test of education, of intellectual training, it is obvious
from what I have said above, that physiology cannot be
put on the same level with chemistry and physics. At
the same time, if such subjects as physiology or botany
are excluded from scholarship examinations, no little
injustice, it appears to me, is likely to be done in the
following way. A lad, let us say, shows an early bent
towards physiology, and acquires at school a very con-
siderable knowledge of its rudiments. His future career
depends on his gaining a certain scholarship. If in the
examination for that scholarship his place depends solely
on the way in which he has acquitted himself in chemistry
and physics, in which his interest isofasecondary character
— he regarding them merely as helps to physiology the
world may be robbed of an eminent physiologist. Hence
I would say that if the evil of a scholarship examination
must come, I would give an opportunity of an elementary
knowledge ol physiolog)' being, in some way, rewarded.

NOTES.

Prof. Ramsay has been good enough to forward to us
the following translation of a passage in a letter he has recently
received from Prof. Olszewski : " I have at last succeeded in
determining the critical temperature and the boiling-point of
hydrogen. I have found for the former - 233° and for the
latter -243'. I havejuied the dynamical melho<l, which I
desciibed in the Philoiophicat Afai;tr-ine .\ thermal couple
proved of no use, and I was obliged to avail myself of a
platiDum-wiic Ihcrmomeler, measuring the temperatures by the

NO. 7325, VOL. 51]

alteration in resistance of the wire. I have obtained satisfactory
results, and intend to publish an account of them in English."

Mr. Frederick Weui: has piesenttd the sum of /looo to
the Medical School of St. George's Hospital, to found an annual
prize in bacteriology.

Prof. Victor Horsley, F.R.S., has been elected into the
Atheraeum Club, under the provisions of the rule which em-
powers the annual election by the committee of nine persons
'■ of distinguished eminence in science, literature, the arts, or
for public services. "

We are glad to learn that there is no foundation for the
report of the death of I'rof. H. Wild, of St. Petersburg, noted
in these columns on February 2S. The mist.ike arose owing to
the announcement of the decease of a German investigator of
{he same name.

At the meeting of the Royal Irish Academy, on March 16,
the following were elected honorary members. In the section
of Science : Dr. Karl Weierstrass and Prof, du Bois Reymond,
and Prof. E. Suess. In the section of Polite Literature and
Antiquities: Prof. A. Erman, Dr. E. Zeller, Lieut. -General H.
L. F. Pitt- Rivers, and Mr. S. R. Gardiner.

At the Paris Academy of Sciences last week, a bronze medal,
engraved by Chaplain, was presented to M. Bertrand, in
honour of his jubilee. The medal has on one side a likeness
of M. Kertrand, and the reverse side bears the following senti-
ment : "To Joseph Bertrand, member of the French Acidemy,
Perpetual Secretary of the Academy of Sciences, in honour of
fifty years' devotion to science and education, from his pupils,
admirers, and friends. March, 1844-1S94."

The Acniversaty Dinner of the Fellows of the Chemical
Society will be held at the Hotel Mctropole on Wednesday,
March 27, when Dr. Henry E. Aimstrong, President of the
Society, will occuj y the chair. The Right Hon. A. J. Balfour,
M.P., James Brjce, M.P., the Piesidents of some of the
learned Societies, and several other distinguished guests have
accepted invitations to the dinner.

A NUMBER of organisations for scientific research in the
le.idi rg cities of the .American sea-board, including Philadel-
phia, Princeton, New Yoik, Biookljn, and Boston, have com-
bined to organise an exptdition to the west coast of Greenland.
The expedition will be fitted out at Newfoundland, and will
sail next June. Elaborate preparations are under way to insure
important results to science. Each of the Societies participat-
ing will send a representative, including several who went last
year, such as Profs. Libley and Chambcrlin. The Brooklyn
Institute will send a representative, to be chosen hereafter.

The death is announced of Mr. A. W. Beelliam, at Dawlisbi
in his ninety-fifth year ; he was elected a Fellow of the Royal
Society in 1835. We also notice the death of Mr. J. C. Smith,
presi dent of the Institution of Civil Engineers of Ireland ; of
Dr. Htrmann Grote, one of the most eminent experts in
numismatics ; of Mr. (I. N. Lawrence, a leading American
ornithologist ; of General de Nosouty, founder and director of
the Pic du Midi ( Ihservatory, which for twenty-one years has
rendered great service to agriculturists in the I'rench Pyrenees ;
and of Prof. Julien Brunhes, at Dijon.

The Belgian f Academy of Sciences offers a prize of 600
francs for the best essay on each of the following subjects :—
(i) On the number of chromosomes before impregnation in an
animal or a plant ; (2) On the Quaternary Flora, especially
that of peat-bogs; (3) Is there a nucleus in the Schizophyta?
if so, what is its structure and its mode of division? The
essay must contain a critical review of the publications existing
on the subject. Each essay must be the result of original
investigation.

March 21, 1895]

NATURE

489

The Bologna Academy of Sciences offers a gold medal
having the value of one thousand Italian lire (Cv^^ ^^ ^ prize
to the author of a memoir which describes the best system
or new apparatus for preventing or extinguishing fires, by
chemical, physical or mechanical means. The competition is
open to persons of all nationalities, and the memoirs must
reach the Secretary of the Academy before the end of May,
1S96. The descriptions should be written in Italian, Latin, or
French, but memoirs will be permitted to compete if written
in any other language, provided a translation in Italian accom-
panies them.

The Times correspondent at Cairo reports that the Council
of Ministers has approved Mr. Garstin's proposal for clearing
Phila; of debris, in order to make a thorough examination of the
bases of the temple;, and explore the subterranean passages
which intersect the island. This work, which is of high im-
portance to the scientific world, will be done by the Public
Works Department, an oft'icial from the Antiquities Depart-
ment attending to insure that all objects of interest are pre-
served. The Ministry of War will be asked to lend Captain
Lyons, R.E., to superintend the work.

The United States Government is (we learn from the British
Medical yournal) about to undertake an investigation of the
climates of the country in connection with the indigenous
diseases. The investigation will be conducted by the Weather
Bureau of the Department of Agriculture, the Chief of which,
Mr, Mark W. Harrington, has on many previous occasions
given proof of an active interest in sanitary climatology. The
precise manner in which the results of the investigation will be
made public has not yet been decided upon, but it is hoped
soon to publish a periodical devoted to climatology, and its
relations to health and disease.

By the consent of her Majesty the Queen, a piece of ground
— the Palace Meadow — about four and a half acres in extent,
has been ceded to the Royal Gardens at Kew, for the use of the
public. The concession is a great convenience, for the removal
of the fences will allow visitors to make a direct, instead of a
circuitous, access to the finest part of the Arboretum. The
<Jardensare 251 acres in extent. It is not generally understood
(says the A'ew Bulletin) that they were originally the private
property of the Crown, and not acquired out of public funds.
The building used for the Herbarium and Library was sold to
the nation by George IV. Access to the remainder has been
step by step conceded to the public by the liberality of her
Majesty the Queen,

The annual general meeting of the Italian liotanical Society
will be held this year in Palermo, from April 16 to 23. The
opportunity will be taken of celebrating the hundredth anni-
versary of the foundation of the Botanic Garden at Palermo.

On Thursday next, March 28, Dr. E. B. Tylor, F,R.S., will
deliver the first of a course of two lectures at the Royal Institu-
tion, on " Animism as shown in the Religions of the Lower
Races." The Friday evening discourse, on March 29, will be
delivered by Dr. H. E. Armstrong, F.R. S. His subject will
be "The Structure of the Sugars and their Artificial Produc-
tion."

The Zoological Society of France held its second annual
reunion on February 2S, under the presidency of Prof.
Leon Vaillant. The meeting was a marked success, a number
of zoologists from all parts of France favouring the Society
with original communications. It has been decided to make
these annual conferences, to which all naturalists are cordially
■welcomed, a permanent feature, and to arrange in future for
■microscopical and other demonstrations, as well as numerous
:SOcial gatherings.

NO. 1325, VOL. 51]

When the Council of the Zoological Society of France voted
to support the movement for the establishment of an inter-
national bibliographical bureau, it charged one of its members.
Prof. E. L. Bouvier, to present a report at the annual reunion of
the Society. Basing its decisions upon this report, the Society
has nominated a central Committee of Management, composed
of the following titular members: — Dr. Raph. fslanchard. Prince
Roland Bonaparte, Prof. Ives Delage, Prof. Henri Filhol, Prof.
Albert Gaudry, Baron Jules de Guerne, Prof. A. Milne-Edwards,
and Prof. A. Raillet. Twenty zoologists, residing ia various parts
of France, have been nominated as associate members. To
complete the organisation, eleven special correspondents have
been appointed, whose duty will consist in reporting to the
Bureau such works as are inaccessible to it, A preliminary
inquiry among the various scientific societies and the
leading publishers has shown, however, that nearly all
the zoological publications of France will be sent gratuitously
to the Central Bureau. Not a single failure to accept this in-
vitation to co-operate has thus far been reported.

The annual meeting of the German Zoological Society will
be held this year at Strassburg, on Tuesday, Wednesday, and
Thursday, June 4 to 6, A preliminary general programme of
the meeting has already been issued, and in the list of papers
promised for, the occasion we notice one by Prof. Goette, " On
the Ancestry of the Vertebrata," and another by Dr, Biirger,
" On Nemertines." The mornings will be devoted to general
business and the reading of scientific communications and re-
ports, and the afternoons will be reserved for demonstrations and
the inspection of the laboratories. The meeting should possess
considerable interest, and many will probably be glad to avail
themselves of the cordial invitation which the Society extends
to zoologists of other nationalities to attend the meeting as
guests, and to take part in the proceedings of the Society,

The Paris Geographical Society has awarded its prizes for
189s, as follows : — Gold medals, to Lieut. L. Mizon, for his ex-
plorations in West Africa ; E Gautier, for his explorations in
Madagascar ; F. Foureau, for his explorations in the Sahara :
E, Ponel, for his explorations in the region of the French
Congo ; Th. Moureaux, for his magnetic map of France ;
Father Colin, for his observations and triangulations in Mada-
gascar ; .\. Courtry, for the production of a map of the Congo ;
V. de la Blache, for his general atlas ; and Dr, Thoroddsen,
for his explorations in' Iceland. Silver medals have been
conferred upon E, D. Ponclns, for his journey from Turkestan to
Kashmir by the Pamirs ; J. Gaultier, for his works on the pro-
duction of plans by photography; B. d'Attanoux, for his ex-
ploration in the Sahara ; and J, Forest, for his studies on the
breeding and habits of the ostrich in the Sahara. The Jomard
prize has been awarded to L. A, Rainaud, for his memoir
entitled " Le Continent austral : hypothese et decouverte. "

Since the decision in the case of the Leeds Sunday Lecture
Society, when it was held that the delivery of a lecture on a
Sunday came within the meaning of the " Act for Preventing
certain Abuses and Profanations on the Lord's Day, called
Sunday," if the public were not admitted free, the Sunday
Society h.-is been exerting itself to procure an amendment of
the vexatious Law as it now stands. Lord Ilobhouse, who
presided at a conference of Sunday Societies held last month,
has introduced a Bill into the House of Lords for amending
the Act in accordance with a resolution passed on that occasion.
The Bill aims at securing that in future — "No action for the
recovery of any penalty shall be commenced against any person
in respect of the opening of any Museum, Art Gallery, Science
or Art Exhibition, Garden or Library, as such, or the delivery
of [any lecture on science, literature, art, or kindred subject,
or any recitation, or the giving of any performance of music,

490

NA TURE

[March 21, 1S95

either vocal or iastrumenlal, on SunJay, providsd ihat the
same take place under the management and control of a Society,
Commitiee, or other body of persons, for ihe public advantage
and not for pecuniary profit."

It is proposed to hold an International Exhibition at Atlanta,
Georgia, U.S.A., from September iS next, to December 31.
The classification includes the usual departments of Intern itional
Exhibitions, the following bein^ the divisions :— .Minerals and
Forestry ; Agriculture, Food and its accessories. Machinery and
.\ppliances ; Horticulture, Viticulture, Pomology, Floriculture,
ic. : Machinery ; Manufactures ; Electricity and electrical ap-
pliances ; Fine Arts, Painting, Sculpture, and Decoration ;
Liberal Arts, Education, Literature, Music, and the Drama ;
Live Stock, Domestic and Wild Animals, Fish, Fisheries, and
Fish Culture ; Transportation. The United States Government
have given permission for exhibits to be brought in free of
Customs' duties, unless the goods are entered for consumption
in the States. Exhibits are invited from foreign countries on
the usual conditions. Further information may be obtained from
the Director-General, Mr. C. A. Collier, Piedmont Park,
.\tlanta, Georgia, U.S.A. Copies of the classification and
general regulations have been sent to the Secretary of the
Society of Arts, and can be seen at the Society's offices by any
persons interested.

At a recent meeting of the Oriental Club of Philadelphia
(Dr. D. G. Brinton writes in Science), Dr. J. P. Peters, whose
researches among the ruins of the valley of the Euphrates are
well known, mentioned his observations on the deposition of
alluvium by the river as a chronometer for measuring the
antiquity of some ruinmouads. Tne deposits from thi known
date of Alexander's conquests display marked uniformity ; an d
taking the depths of these as a standard, the foundations of U r
(the " Ur of the Chaldees " of Genesis, the modern Muchair)

and of Eridu (the modern Abu-Shahrein) must have been laid

about seven thousand years B.C.

A SUBSTITUTE for wood is badly wanted in the construction
of warships. In the recent actions between the Chinese and
Japanese fleets, several ships were disabled by serious fires on
board, and this has caused much attention to be given to the
invention of artificial wood, both at home and abroad. A Boird
of experts, says the Journal of the Franklin Institute for
March, was lately convened by direction of the Secretary of the
U.S. Navy to consider the subject of dispensing with wood in
the construction of the naval ships now building, and also for
the purpose of finding some suitable substitute for wood where
it ii impracticable to use metal. The Board has decided that a
substitute for wood should be light, or not heavier than wood,
non-condncling, non-combusiible, and, when struck by shot,
should not fly into splinters. Wood has the very objectionab le
property of splintering from the effect of slut ; and the fact is
well known that, in wooden ships, frequently as many persons
are wounded by splinters as by shot.

A SOLUTIO.N of the problem of finding a substitute for wood,
teems,' in the opinion of the Board, to lie in (he following
direction: — Select something in the nature of cheap wojd or
vegetable fibre and fine sawdust ; treat tbem chemically w ith
tome insoluble fire-prooi substance, not too heavy ; then press
and roll into boards, more or less dense, according to the use
for which the material is desired. Such a miterial will be non-
inllammablc all through, will not splinter, will not be heavy,
and will be a nonconductor. Possibly this artificial board can
be strengthened by enclosing within it a lough, fine wire net-
ling. If uwdusi, or other fine cellulose material, after being
rendered non-inflammable, can, by mixing with other materials
not too heavy -or, if heavy, in small quantiliei — be applied to
NO. 1325, VOL. 51]

metal in a plastic state, so as to harden into a compact mass
impervious to water, then it will be of great value. In other
words, if a light, non-conducting, non-inllammable, insoluble
cement can be discovered, it will be of great use in ship con-
struction.

Numerous objects made of wood and covered with copper
have been found during the exploration of mounds in Ohio.
Prof. F. W. Putnam has described specimens of this kind, and
copper objects sheathed with silver. The examples found are
quite sufficient to show that the American aborigines in the
Mississippi valley and in South .\merica had the art of cold-
hammering copper, of heating it to overlieand fit upon a warped
or curved surface, and of turning the edges under. This pro-
cess must not be confounded with the mere hammering-out of
implements, nor with the process of making a sheet of copper
as thin and uniform as a ship's sheathing, and then producing
figures by rubbing or pressure. A note by Prof. O. T. Mason,
in ihe J'rocecdings ol the U.S. National Museum (vol. xvii.
No. 1015), shows that the Haida Indians, who occupy the
Queen Charlotte Islands, and are famous for their carved work,
also cover wood and bone with copper. He describes two figures
of humming-birds carved in wood, and having their wings and
tails overlaid with a covering of sheet copper. The surfaces are
neatly engraved with the conventional wing and eye signs of
the Haidas. These specimens, and those from the mounds of
Ohio, throw some light upon the processes employed by the
aboriginal metallurgists of America.

It will be remembered that in June last, Piof. C. V. Riley
resigned his position as Chief of the Division of Entomology
of the United States Department of Agriculture, and was suc-
ceeded by Mr. L. P. Howard. Owing to these changes, the
publication of Insect Life — the premier of entomological
bulletins — appears to have ceased for a time. The periodical
has, however, been revived, and three numbers of a new
volume (vol. vii.), edited by Mr. Howard, have come to us,
together with the last number of vol. vi., published under the
joint editorship of I'rof. Riley and Mr. Howard. Each of the
numbers contains a store of information, in the form of articles
or notes, on the life-habits of insects, especially in relation to
agriculture. In one (vol. vi. No. 5) we notice an address on
"Bees," by Prof. Riley, and in another (vol. vii. No. I) we have
an illustrated description of the senses of insects, by the same
writer. The second number of the new volume is devoted to
the proceedings of the sixth annual meeting of the Association
of Economic Entomologists, held in August 1894. The
presidential address delivered by Mr. Howard on that occa-
sion, dealing with the rise and present condition of onicial
economic entomology, shows what ollicial encouragement is
given to the investigation of insect problems in all parts of Ihe
world.

Most of the great advances in entomology have come
from America, but, as Mr. Howard paints out in the
address referred to above, this progress would not have
been possible without legislative encouragement. At the
present lime ihe amount of money expended for work in
economic entomology is far greater in the United States than
in any other country. There the regular annual expenditure in
the support of entomological oflices amounts to about one
hundred thousand dollars. Probably the total sum expended
annually in experiments and publications exceeds the entire
amount expended in the same direction by thr remainder of the
world. No wonder, then, that the whole world looks to
America for instruction in economic entomology. And the
results obtained justify the money expenditure. Not a year
passes, Mr. Howard remarks, in which the sum saved to agri-
culture and horticulture, as the direct result of Ihe investigations

March 21, 1895]

NATURE

491

of entomologists, does not amount to many times that which
' the United States Government grants. The results have thus
added greatly to the pioductive wealth of the world, and this
fact alone should be sufficient to lead our own Government to a
more generous recognition of work in economic entomology.

Several German periodicals have published an account of
a remarkable balloon ascent made in the " Phoenix " by Dr.
A. Berson, on December 4 last. The balloon was inflated
with 70,600 feet of hydrogen, and ascended from Stassfurt
( Prussia) in the morning, taking a north-westerly direction, the
weather at the time being somewhat misty. The temperature
at first increased up to a considerable height ; at 4900 feet the
thermometer stood at 41', and at 16,400 feet it read o , with a
very dry air. At noon, an hour and half after starting, a height
of 22,150 feet was reached, and the lliermometer fell to -20'.
At this time Dr. Berson began the artificial inhalation of oxy-
gen, with excellent results. At about 29. 500 feet the balloon
passed through a veil-like stratum of cirrus clouds; these did
not consist of ice crystals, but of perfectly formed flakes of
snow. About two and a half hours after starting, a height of
about 31,500 feet had been reached, the thermometer dropped
to -54°, and indicated only -11° in the sun's rays; at this
height Dr. Berson, being alone, thought it prudent to com-
mence the descent. At 4600 feet the highest temperature was
recorded, viz. 43°, and between this point and the earth it
dropped to about 34 : The ascent occupied 3 hours, and the
descent 2h. 20m., the balloon having travelled 1S6 miles,
notwithstanding that the wind was almost calm on the surface
of the earth. Dr. Berson obtained observations at a greater
altitude than they had before been made ; in Mr. Glaisher's
celebrated ascent of September 5, 1862, the last actual obser-
vation was at 29,000 feet, although it is supposed that the
balloon rose at least 7000 feet higher. The above particulars
are taken from an account given in the American Engineer for
this month.

About three years ago, the Botanic-Garden at Cape Town
was transformed into a town garden supported by municipal
rates. A similar change has lately taken place at King
William's Town, in the eastern province of the colony. The
k'e-Ji' Bullelin for March rightly condemns these changes, and
the perfunctory manner in which botanic gardens in South Africa
have generally been treated. It points out that, at the present
m oment. Cape Colony is the only important British possession
w bich does not possess a fully-equipped botanical institution.
It is true it possesses a fine colonial herbarium, undei the com-
petent charge of Prof. MacOwan, and an agricultural depart-
ment which he efficiently advises on botanical subjects. But
b eyond this it has no central authority dealing with the practical
aspects of the science of botany, and no gardens under
technical control where careful experimental cultivation could
be carried on, or where special seeds and plants could be ob-
tained for starting new industries. This condition of alTairs,
the Bulletin holds, is scarcely credible to a large and wealthy
community like that at the Cape. Something more than an
ornamental garden, dotted here and there, is required in South
Africa. A central establishment in the neighbourhood of Cape
Town, devoted to the scientific study and experimental cultiva-
tion of plants, fully equipped to discharge its studies as a
national institution on the lines of Kew, would alone be worthy
of the future of South Africa. The flora of this part of the
world is one of extreme interest. It deserves to be carefully
and exhaustively studied, and numerous plants, now in danger
of becoming extinct, should be preserved in some central spot
for the observation of students. Of the economic influences of
such a central institution it is needless to enlarge. There are
hundreds of problems connected with the cultivation of in-
NO. 1325, VOL. 51]

dustrial plants in South Africa awaiting solution, and these
could only be dealt with at an institution specially devoted to
scientific research, where careful trials could be conducted ex-
tending over many years.

In a recent publication by Dr. L. A. Bauer, entitled "Beit-
raege zur Kenntniss des Wesens der Saccular Variation des
Erdmagnetismus " (Inaug. Diss., University of Berlin), some
interesting and important contributions to our knowledge of that
enigmatical phenomenon of terrestrial magnetism^the secular
variation — have been made. The author has constructed the
actual curve described in the course of centuries by the north
end of a " free magnetic needle " at various stations (24) dis-
tributed over the globe. The result has been the establishment
of a law governing the direction of the curve, which the author
claims is the first law that has been established thus far with
regard to the secular variation as applying to the whole earth.
This law may be expressed as follows: — The north end of a
freely suspended magnetic needle, as viewed from the point of
suspension of the needle, moves, in consequence of the secular
variation of terrestrial magnetism on the entire earth, in the
direction of the hands of a watch. With regard to the period.
Dr. Bauer believes that it has not yet been proved that the earth
actually possesses a common secular variation period. The
only way he thinks it possible to deduce a common period is by
the supposition that the curve described by the magnetic needle
is not a single closed one, but consists of loops. Indications of
such loops, he says, make themselves apparent at various
stations. A comparison is also drawn between the secular
variation and the momentary distribution of terrestrial magnet-
ism. A secular wave is followed around the earth with the aid
of the projected curves. It would appear as though a con-
tinuation of the secular curve is obtained by going around the
earth eastwardly. The fact thus revealed, the author says,
would have, as a direct consequence, that if a survey be made
along a parallel of latitude in an easterly direction, a similar
motion of the magnetic needle would be encountered as in the
case of the secular variation. Dr. Bauer has carried oat this idea
for three epochs, viz. 1780, 1829, and 18S5, and along several
parallels of latitude. The curves described by the needle are
projected and given on a special plate. It has been found that
in every case the north end of the needle, as observed from the
centre of the needle, moves clockwise. Furthermore, by a
comparison of both sets of curves — the secular and the momen-
tary— it would appear as though they are subject to similar
laws.

The method adopted in thePhysikalisch-TechnischeReichs-
anstalt for turning true spheres is described by Herr von
Liechtenstein in the /.citichrift fiir InstrunientenkuniU. Three
grinding cylinders, the diameter of which is less than that of
the sphere, are mounted in a lathe, two of them being carried
by one head and one by the other. They are disposed at angles
of 120° to each other in a horizontal plane, and grasp the sphere
between them. Their rotation produces a perfectly irregular
motion of the sphere, and between the three cylinders it is
ground to an extraordinary truth of figure. Iron and steel
spheres of 25 mm. diameter thus produced showed errors of
diameter not exceeding 0'OOI5 mm.

In the yearly report of the Russian Geographical Society, we
notice that M. Roborovsky, chief of the Tibet expedition, has
m.ide a careful survey of the Lukchun depression, the level of
which, as is known, lies below the level of the ocean. It appears
that the depression has a length of nearly too miles, and an
average width of 50 miles, and that its level is from 100 to 150
metres below the level of the sea. The desert which is situated
in the south of it was crossed in several directions, and M.
Roborovsky succeeded in obtaining no less than six speci-

49'-

NATURE

[March 21, 1895

mens of the wild camel. After having reached Sa-chou,
the expedition miie extensive surveys in the Nan-shan high-
lands, and then ic went out for the exploration of the country
in the east of Lake Kukunor.

With reference to Mr. Culverwell's recent criticism of the
astronomical theory of the Ice age, the Rev. O. Fisher [^Giol.
Mag. for March) quotes the opinion of the late Prof, .\dams,
expressed to him in a letter dated February 2S, 1S66. He says :
"I do not myself believe in the change of eccentricity of the
earth's orbit being a cause of climatal changes on the earth.
The efifect, if any, would depend only on the s::iart of the
eccentricity ; and this always remains so very small, that I
believe the effect on the earth's mean temperature would be
almost insensible. Depend upon it, geologists who look in
this direction for the cause of glacial epochs are entirely on the
wrong track. It seems to me much more likely that the actual
act of emission of heat from the sun is variable, than that the
change of eccentricity of the orbit should have any sensible
effect."

Prof. F. Brioschi read before the .Vccademia dei Lincci, on
March 3, a very full account of the life and works of the late
Prof. Cayley, who was a Foreign Associate of the Academy.

A WORK almost entirely concerned with Insurance statistics
is "Bourne's Handy Assurance Directory," now carried on by
Mr. W. Schooling. Every one interested in statistical in-
formation relating to human life will find the volume useful.

Is the "Handbook of Jamaica" (Stanford) for 1895,
compiled by Mr. S. P. Musson and Mr. T. L. Roxburgh, short
biographical descriptions are given of the men of science who
have been associated with the island, in addition to the
historical, statistical, and general information concerning it.

The number of the BuUclin of the Uotanical Department,
Jamaica, for January 1895, edited by the Director, Mr. W.
Fawcett, is largely occupied with the insect enemies of the
cocoa (Thtoliroma) and pine plantations, and some of the
Coccida; or scale-insects. It also contains a very interesting
report on the services rendered in the island by the Botanical
Department of Jamaica.

With the March number, Science Progress commences its
third volume. Dr. E. Klein, F. R.S., contributes to the num-
ber an article on antitoxin, and Mr. J. E. Marr, K. R. S.,
summarises recent literature concerned with foreign work
among the Precambrian and Pal.xozoic rocks. The subjects
of the remaining articles are : — " Insular Floras," by Mr.
W. B. Hemsley, F.R.S. ; "Peptone," by Dr. \V. D. Halli-
burton, F.R.S. ; "Budding in Tunicata," by Mr. \V. Garstang;
and "The Reserve Materials of Plants," by Prof. J. R. Green.

The first part of Mr. C. B. Moore'svaluable report of his
excavations in the prehistoric sand mounds of the St. John's
River, Florida, was noticed in these columns last November
(vol. li. p. 27). The second part, which has now reached us,
contains the results of seven months' continuous work upon all
the remains that could be found, and the complete report
practically exhausts the study of the mounds on the banks of the
St. John's River ; for the river has been explored from the
source to its outlet. The mounds described in the part of the
report before us are, perhaps, not quite so interesting as those
of which an account was given in the former part, but this does
not diminish their value to archxologists. Future workers among
the moundi will find that all the objects found are recorde<l,
instead of merely the rare ones, and those of unusual workman-
ship. The flint implements, curious types of earthenware, and
human remains described, and finely illustratol, furnish ni.itcrlal
for much scientific study. The Philadelphia .Academy of

NO. 1325. VOL. 51]

Sciences, in the yournal of which (vol. x.) Mr. Moore's report
appears, deserves much credit for the admirable illustrations.

Meteorologists and physicists have reason to be grateful
to Mr. S. P. Langley for the valuable series of numerical tables
which he has projected, to take the pl.ice of a series of
meteorological tables compiled by Dr. .Vrnold Guyot, and
published by-the Smithsonian Institution in 1S52. Dr. Guyol's
tables were widely used and appreciated, but the new series
will be of even greater service. The work will be completed
in three parts : Meteorological T.ibles, Geographical Tables,
and Physical Tables. The first of these volumes appeared in
1S93 ; the second (Smithsonian Miscellaneous Collections, No.
S54) lies before us. This has been prepared by Prof. R. S.
Woodward, whose experience in geodetic work particularly
qualifies him for the task. The introductory p.irt of the
volume is divided into seven sections, under the heads : useful
formulae, mensuration, units, geodesy, astronomy, theory of
errors, and explanation and use of tables. This section takes
up a hundred pages, after which come tables running into one
hundred and eighty pages. Every effort appears to have been
made to avoid errors, and Prof. Woodward has made a
judicious selection of matter from a vast amount of available
material. It requires no great prophetic instinct to say that
his compendium will be prized by geographer and meteorologist,
as a standard work of reference.

The Meteorological Society of Berlin has published its
Report for the year 1895 ; the Society holds monthly meetings
between October and May, and a summary of the papers read
is regularly printed in our columns. Prof. Hellniann, the
President, appends to the Report a discussion of the wind
velocity at Berlin from ten years anemometrical observ.itions.
The principal maximum, in the yearly period, falls in M.ivch, and
the minimum in September ; in the daily period, the maximum
throughout nearly the whole year occurs between ih. and 2h.
p.m., with a tendency to a second maximum during the night
in the cold season. The greatest hourly velocity recorded was
fifty miles an hour, which is about half the rate that has beei»
registered in the greatest storms on our own coasts.

We have received from Dr. Henry Bovey a paper of high
technical value, containing the results of numerous experiments-
which have been carried out in the testing laboratories of the
McGill University, on the strength of Canadian Douglas fir,
red pine, white pine, and spruce. The tables given tend to
prove that timber, unlike iron and steel, may be strained to a
point near the breaking-point without being seriously injured.
In almost all cases the increments of deflection and extension,
almost up to the point of fracture, are very nearly proportional
to the increments of load, thus showing that it is difficult to
define a limit of elasticity for timber. This, Dr. Bovey thinks,
probably accounts for the continued existence of many timber
structures of wood in which the timbers have been, and are
still, continually subjected to excessive stresses, the factor of
safety being often less than one and a half. Whether it is
advisable so to strain limber is another question, and experi-
ments are still required to show how, wood is affected by
frequently repeated strains.

A further memoir concerning the interesting sodium
derivative of nitro ethane, and the sodium compounds of nitro-
paraffins generally, is contributed by Prof. Victor Meyer to the
Beriihte of the German Chemical Society. The nature of
these unstable compounds has not hitherto been satisfactorily
determined, for in a communication to the AnnaUn der Cliemit,
J. U. Nef, some lime ago, stated th.it they do not partake of
the nature of true derivatives of nitro -paraffins, but contain
an altogether differently constituted organic residue. The ex-

March 21, 1895J

NA TURE

493

perimental evidence adduced in support of this view consisted
chiefly of the observation which he made that the pirent nitro-
I paraffin was not, or only to a slight extent, regenerated upon
treating the sodium compound with dilute sulphuric acid, the
I compound being decomposed with evolution of nitrous oxide and
' formation of aa aldehyde or ketone. Prof. Meyer has made
further experiments in Ihii direction, and their results definitely
fix the nature of these sodium compounds, proving that they
are indeed true sodium derivatives of the nitro- paraffins, being
formed by the replacement of one of the hydrogen atoms of
the alkyl radicle by sodium. It is a fact that when sodium
nitro-ethane, CjHjNaNO,, is dissolved in excess of dilute sul-
phuric acid at the ordinary temperature, a somewhat vigorous
evolution of nitrous oxide occurs. But if the most elementary
precautions are taken to prevent the decomposition of so
unstable a substance by the thermal change involved in so
energetic a reaction, the decomposition proceeds quite dif-
ferently. If the sodium compound is first dissolved in a little
water well cooled by ice, .ind then an equivalent added of
dilute sulphuric acid similarly cooled to near o", only a very
few bubbles of gas escape, and barely a trace of the odour of
aldehyde is perceptible, while a layer of oil, consisting of nitro-
ethane, separates out. Even afier the operations of purification,
which involve some loss owing to the volatility of nitro ethane,
over 60 per cent, of the theoretical quantity of the pure nitro-
paraffin was isolated. Moreover, the small quantity ot decom-
position indicated by the few bubbles of nitrous oxide can be
entirely avoided by employing acetic instead of sulphuric acid ;
the reaction is then less vigorous, ani consequently produces at
temperatures not far above 0° no dissociation of the nitro-
paraffin. The observation of Nef, that the sodium derivatives
of the nitro-paraffins are decomposed at the ordinary tempera-
ture by the stronger acids, even when diluted, into nitrous oxide
and an aldehyde or ketone, is an interesting one ; but Prof.
Meyer's work now shows that this is due merely to the fact
that the nitro-paraffin first regenerated is decomposed in all
probability by the heat of the reaction between the sodium and
acid, and that when the precaution is taken to prevent this
rise of temperature by reacting with ice-cold solutions, the re-
generated nitro-paraffin remains intact. Hence it must be con-
cluded that the sodium compounds are true derivatives of the
nitro-paraffins which can thus be regenerated from them.

The additions to the Zoological Society's Gardens durmg the
past week include a Vervet Monkey (Cercopithecus lalandii, 9 )
from South Africa, presented by Captain Scarlett Vale ; a
Macaque Monkey {Macacus cynomolgus, i ) from India, pre-
sented by Miss K. Fleming ; a Vulpine Phalanger {Phalangista
vulpina) from Australia, presented by Mr. Richmond Allen ;
a Grey Ichneumon [HerpesUs griseus) from India, presented by

Mrs. Lewis; fifteen KaXsi^Miis, sp. inc.) from Sunday

Island, Kermadee Group, presented by the Countess of
Glasgow ; a Hooded Finch] (Sfierintsles CHCtdlata) from West
Africa, a Chestnut-eared Finch {Amadina castanotis) from
Australia, presented by Mr. C. II. Hastings ; a Woodcock
(Scolopax ruslicula), British, presented by Mr. Charles
Smoolhy ; a Long-necked Chelodine {Chelodina longicollis)
from Australia, deposited ; four Marbled Newts (Molge
marmoraia), European, purchased.

OUIi ASTRONOMICAL COLUMN.

Partiai, Eclipse uf the Sun, March 26. —On March 26
a small partial eclipse of the sun will, if the weather be favour-
able, be seen from all parts of the liritish Isles, with the pro-
bable ex;eption of places which are to the east of a line
joining Liwistift an 1 Ilistin^s. At Greenwich the magnitude
of the eclipse, sun's diameter = i, will hi 0013, and the first
contact will occur at 9 56 a.m., with a duration of only 27

NO. 1325, VOL. 51]

minutes. At Oxford the magnitude will be 003, and the
duration 40 minutes. At Dublin the magnitude will be O'og,
with a duration of 67 minutes, and at Edinburgh 008, with a
duration of 62 minutes. The eclipsed part will be a maximum
(o"36) as seen from the north-east of North America.

In the Nautical Almanac for the current year the eclipse is
said to be invisible at Greenwich, but the error was corrected
\a\he Almanac for 1897. The mistake, however, has not been
corrected in many of the almanacs in common use.

Distribution or Minor Planets. — An interesting dia-
gram has been constructed by General Parmenlier, to show
the distribution of the minor planets at present known between
the orbits of Mars and Jupiter (Bulletin Soc, Ast. de France,
March). jOf the 390 planets for which sufficient data are
available, 93 have a mean distance between 2"i6 and 2"4S;
152 between 252 and 2'82 ; 128 between 2'S5 and 3"25 ; and
10 between 3-38 and 3'48. The interval between Brucia (at
2'l6) and Mars, is occupied by a single asteroid, comparatively
recently discovered, with a mean distance of 2'09. On the
outer side of the dense swarm, there are only six minor planets
in a zone very nearly as wide as that occupied by the group of
383, and extending to a mean distance 4'68. The region of
greatest density of the asteroids so far discovered is at a mean
distance from the sun very nearly equal to that indicated by
Bode's law (2'8o) ; Ceres, Pallas, and Juno fall a little short of
this distance.

At the present rapid rate of discovery of minor planets by
the photographic method, data will no doubt soon be available
to determine if the outer zone between Camilla and Jupiter is
really an almost deserted region.

The Royal Observatory, Edinburgh.— We are glad to
hear that the new National Observatory for Scotland is making
rapid progress towards completion. The buildings are quite
finished so far as the outside is concerned, and it is hoped that
the two cquatorials and the transit instrument will be erected
in the early summer. The library will be ready to receive the
magnificent collection of twenty thousand volumes as soon as
the heating arrangements are completed.

PHYSICAL WORK OF HERMANN VON
HELMHOLTZy

II

T/'ONIG has shown that in many cases, when two notes are
sounded simultaneously, beats are heard, as though t!ie most
prominent phenomenon was the production of beats not between
the two fundamental notes, but between the upper of these, and
the nearest partial of the lower note. Inasmuch as these beats are
heard when the lower note (as far as can be tested) is free from
upper partials, this rule is not the explanation of the pheno-
menon, but it is a convenient way of expressing the results. In
the experiment just described, the frequencies of the two notes
were in the ratio 12 to 15. The first partial of the lower note
(12) is therefore the nearest to the higher tone ; that is to say,
Konig's beat tone and the first difference tone are identical.

It is easy to arrange an experiment in which these conditions
are not fulfilled. Thus let the notes be in the ratio 9 : 15.
The second partial of the lower note is 18, which is nearer to 15
than to 9 ; hence the Konig beat-tone would have a relative
frequency of 18-15 = 3. If the siren rotates io'6 times per
second, the frequencies of the two fundamental notes are
9 ;; 106 = 96 and 15 x io6 = l6o respectively. As before, the
difference tone is 64.

In this case we can use another method of determining the
speed of the siren. In 1880 Lord Rayleigh constructed an
instrument in which the mass of air enclosed in a tube is
excited by resonance, and the fact of the excitation is indicated
by a light mirror, which is set where the motion is greatest,
inclined at 45" to the direction of the air-currents. In accord-
ance with the general law that a lamina tends to place
itself perpendicular to the direction of a stream, the mirror
moves when the air vibrates. In the original apparatus the
.amount of the movement was controlled by magnets. Since
that date Prof. Boys has modified the instrument by substitut-
ing a quartz thread suspension for a silk fibre, and using the

^ A discourse delivered at the Royal Institution, by Prof. A. W. Riicker,
F.K.S., OD Friday, March S. (Continued from page 475.)

494

NA TURE

[March 21, 1895

torsion of the tliicad instead of the directing force of the
magnets. In a lecture delivered before the British Asociation,
in Leeds, he exhibited the apparatus, which is sometimes called
a mirror re-ocalcr. Prof. Boys has been good enough to make
two of these isutnimenis for me, and for reasons, which I will
not at the moment enter into, we decided that one of them
sboald respond to i6l vibrations per second. It so happens
that this coincides almost exactly with the frequency of one of
the notes in the experiment under discussion (l6o). It
is ibns possible to use the miiror resonator as an auxiliary
instrument to test the speed of the siien. AVhen the proper
note is reached the spot of light will move, and if the diffrrence
tone is objective the interference bands ought to disappear
simultaneously. We tried this experiment several times. An
observer, so placed that he could not see the interference bands,
lifted his hand when the spot of light moved. It was quite
extraordinary to note the absolute agreement between his move-
ments and the behaviour of the bands.

By throwing the spot of light and the bands near together
on the screen, the coincidences can be watched by a number of
persons. We have tried whether the diRetence tone is objective
in four cases, and in all have delected it by the disappearance
of the interference bands. The details of the experiments are
collected in the following table. In the fiist two experiments
the first difference tone is, and in the last two it is not, co-
incident with K'inig's lower beat note.

Number of holes j
in siren. '

Difference Tones.

Frequencies.

Difference — and
Konig's bc:it-tones.

15 and 12

16 ,, 12

IS .. 9
18 ., 8

I Major third
Fourth

I M.ijor sixth
Anoctaveand
a major tone \

32"
256
160
115-2

256
192
96

51-2

64
64
64
64

64
64

32
128

Of course the question at once arises, whether, when it can be
distinguished separately, Kunig's beat tone is also objective. I do
not wish to express a final opinion on this point, but I may say
that when the rows of eight and eighteen holes were opened the
speed of the siren was increased till the notes corresponding to
256 and 576 vibrations were produced. Knnig's rote would in
that case have a frequency ol 576 - 2 x 256 = 64. We tried
twice to obtain this. On the second occasion, especially, all
the conditions were favourable, and the experiment was carried
on for a long time. On neither occasion did we obtain the
smallest sign ol an effect on the fork and interference bands.

We must next turn to the summation tone which Ilelmholtz
discovered. It has been a'most universally denied that this
note is objective. Without going into details, it is only neces-
sary to remark that the late Mr. Elli.=, the translator of the
"Tonempfindungcn," \»ho took a dispassionate view of the
controversy, thought that the position .issumed by Helmhollz
had been disproved. To the statement of Helmholtz that "it
was formerly believed that the comMnational tones weie
purely subjective and were produced in the ear itself," Kills
appended the note ; " the result of Mr. Bosanquet's and I'rof.
Preyer"s quite recent experiments is to show that they are so."

Id an experiment on the summation tone, as the total
number of vibrations must not exceed 64, the notes will
be too low to be well heard. I shall therefore use a third
method of determining the rate of speed of the siren. A
mirror attached to the lower plate of the instrument rotates with
it. Concentric with, and lying on this, is a circle of paper with
eighteen cogs. Light rcHeclcd from the mirror passes through
holes in two pieces of tinfoil attached to the prongs of a tuning-
fork. When the fork is at rest, these holes are superposed; but
when the fork vibrates, they move apart, arc closed by the tin-
foil, and only cross each other twice in each complete vibration.
The tuning-fork makes 27*2 vibrations per second, and thus
allows the light to pass 54'4 times per second. But when the
siren makes 3 '048 revolutions per second, the rows of nine
and twelve holes give a summation tone of 64 vibrations,
and each cog moves over 18 .-. 3048 = 54'9, or say 55
times the distance between two consecutive cogs. If the wheel
were viewed 55 times a second, the cogs would appear

NO. 1325, VOL. 51]

stationary, as in that interval each would le replaced by the
next. As they are really seen aboot 54*4 times a second, they
appear to move sltwly lonvatds at ihe rate of about one inter
space in two seconds. When this sjeed is attained the bands
disappear, thus proving the objective existence of the sum-
mation tone.

We have repeated this observation in various ways, and
always with success. The results .trc summed up in the table.

Summation Jones.

Numbers of
holes in siren.

10 and S
•2 ,, 9

16 .. 9

Interval.

Major third
j Fourth
Minor seventh

Frequencies.

35-5

56-57

40-96

28-4

27-43

2304

Sum.

64
64
64

It is, perhaps, a drawback ihat all the notes in these experi-
ments are very low. In order to remtdy this, and also to put
the ni.itler to the test by means of another inst'ument, we have
employed a mirror resonator, which responds to 576 vibrations
per second.

The rows of 15 and 12 holes being opened, notes of 320 and
256 vibrations were produced. When they were sounded
separately, lie noise seemed just to make the resonator move.
\\ ben they were sounded together, the spot cf light was driven
oft the scale, w hen the upper note coincided with that of a 320-
vibration fork, but immediately returned when this pitch was
lost.

The sutrmation lone of 576 vibrations was also obtained by
two ether c< mbinaticns of holes. The 320-'oik was used, and
the disturlance occurred in the one case whtn the pitch of the
upper note given by the siren was nearly the seme as before,
and in ihe other case when it was about a tone higher.

The results are sun.ined up in the table.

Summation Tones.

Numbers of
holes in siren.

15 and 12

16 ,, 12
16 ., 9

lnte^^'aI.

Major third

Fourth
Major sixth

Frequencies.

329-«S
360

256

24685

216

Sum.

576
576
576

I venture to think that these experiments prove the accuracy
of von He!mh( II2. They show th.it the siren, at all events,
dees prcduce objective tones, the frequencies ol which coincide
with those of the fust difference nrd summation tones, .ind that
this slaitinent is valid as regards ihe difTeri nee tone, whether
it is or is not coincident with Kunig's beat-tone.

I have now in one single case tried to convey to you some
Idea of the complexity of the problems with which von
Ilelmholtz dealt. He was the first man who detected a
relation between the surging mass of partials and combination
tones and our sensations of concord and di.scord. The main
facts of his theory are, I believe, generally accepted. On some
points modern opinion has tended lo stray from his views ; one
of these we have studied afresh this evening.

It was the fact that I had to deliver this discourse which led
me to invesligale the (jucslion anew, and therefore I fell
bound to tell you the results we have at present attained. Had
it not been for this, I should not have |)ublishcd them as yet.
We have several improvements of the apparatus in view.
We do not pretend to have covered the field. I do not, there-
fore, wish 10 generalise. My object has been to refute hasty
generalisations. I am conicnt if I have convinced ygU, as I
have convinced myself, that Helmholtz w.is correct in stating
that the siren produces oljectivc tones, whose frequencies
arc equal to the sum and diflerence of their ])rimaries, and
that the methods we have employed have brought to light no
facts < p[ oscd to his view that these notes cannot be explained
as secondary effects of partials, but as phenomena of the first
order — in other woids, as real combination tones.

But brief space now remains to discuss the vast remainder
of his work, and as I have already published an appreciation

March 21, 1895]

NATURE

495

of that (Fortnightly Rnie'M, November 1894), I must content
myself with trying to give you, in a few sentences, some idea of
the range of his intellect.

His investigations on optics were not less important than
those on sound. lie invented the ophthalmoscope, by which
the oculist can study the inmost recesses of the eye. The
theory of colour vision, the theory of binocular vision, the
curious subjective effects which are produced when we de-
liberately deceive our own senses by the stereoscope ; these
subjects he made especially his own.

In the field of mathematics he was the first to define the
peculiar rotatory motion of a liquid known as vortex-motion.
Great men had laid the foundations of hydrodynamics before
him, but all had overlooked the importance and laws of the
vortex. Since the memoir of Helmholtz was published the
subject has been widely studied. Lord Kelvin has originated
the famous vortex-ring theory of matter ; Prof. Fitzgerald has
suggested that the ether may be a complex of vortices, or, as it
has been called, a vorlex-sponge.

On electricity he wrote much — on the theory of the galvanic
cell, on electrolysis, on electromagnetism.

In England, at all events, we give the preference, as regards
the last subject, to the theory and writings of our own Max well.

A lecture, or rather many lectures, might be delivered on
each of these topics, but I prefer to devote the few minutes
that remain to other subiects.

As I have already said, von Helmholtz, in an age of special-
ists, was a universal genius. His intellect CDuld light on
nothing which it did not illuminate. Hence his opinions on
side issues are of more than ordinary importance, his "obiter
dicta" are worth attention, his popular lectures acquire a
special interest. Let us for a few moments turn to these.

The watchword of Helmholtz in dealing with educational
problems is "freedom." Freedom for the student, freedom
for the teacher.

In England we are fond of insisting that there are certain
things which everybody who aspires to academic rank must
know ; of hedging in our students by prescribed courses of
study. We make them feel that general culture is an iron-
bound safe, which they must wrench open before they can
attain the gem of real knowledge, rather than a setting, with-
out which the most profound acquirements seem unattractive
and dull. Yet von Helmholtz, one of the most highly educated
men, one of the most comprehensive geniuses of the latter end of
the century, will have no set courses, except as a preparation for
a definite profession, is proved that Germany has " retained the
old conception of students, as that of young men responsible to
themselves, striving after science of their own free will, to whom
it is left to arrange their own plan of studies as they think
best." Not content with having m.ade the attainment of this
ideal almost impossible for English students, doctrinaire educa-
tionalists are now beginning to thr')W their net around the
teacher. It is claimed that as the student must go through a
prescribed course of study in order to learn, so the teacher must
be drilled and examined before he is allowed to teach. What-
ever can be said f.jr this plan as regards the less advanced class
of teachers, who are to devote themselves to the instruction of
children — and in this case I believe there is something to be said
for it — it is quite opposed to von lielmholtz's view of wh.at is
best when the teaching is of university rank, and the students
are men and women. Make it easy for whoever has given some
proof of knowledge, and wants to teach, to try his hand ; make
it easy for the student to go to the teacher from whom he gains
the most. Look for the best educational results, not necessarily
from the best lecturer, but from the man who is in closest con-
tact with his subject. Do not force your teacher on his
audience, but do all you can to establish a bond of sympathy
between them. Trust, in a word, to the free play of living
forces, and not to the hampering restrictions of "necessary
subjects" and "compulsory lectures." This is a paraphrase of
the views which Helmholtz held, and he illustrated them by
the history of this Institution itself.

"I have often," he said, "wondered that the Roy.al
Institution of London, a private society, which provides for its
members and others short courses of lectures on the progress of
natural science, should have been able to retain permanently
the services of men of such scientific importance as Humiihry
Davy and Faraday. It was no question of gi'eat emolument < ;
these men were manifestly attracted by a select public, con-
sisting of men and women of independent mental culture. ' And
then he goes on to show that in a German university the teacher

NO. 1325, VOL. 51]

is attracted to his work, because he has to deal with a body of
students, who are capable of forming opinions, and of judging
what is best for themselves.

And this leads us to another point. Von Helmholtz insisted
that it is useless and dangerous to crowd the universities with
students, who are not capable of taking advantage of the oppor-
tunities they offer. " The majority of students," he says, " must
come to us with a sufficiently logically trained judgment, with
a sufficient habit of mental exertion, with a taste sufficiently
developed on the best mo lels to be able to discriminate truth
from the bubbling appearance of truth. ... It would be very
dangerous for the universities if large numbers of students
frequented them, who were less developed in [these] respects.
The general self-respect of the students must not be allowed to
sink. If that were the case, the dangers of academic freedom
would choke its blessings. It must, therefore, not be looked
upon as pedantry, or arrogance, if the universities are scrupu-
lous in the admission of students of a different style of educa-
tion. It would be still more dangerous if, for any extraneous
reasons, teachers were introduce t into the faculty, who have
not the complete qualifications of an independent academical
teacher." ("Popular Lectures," vol. ii. 1S81, p. 264-5.)

It would be out of place on this occasion to attempt to apply
these views to existing circumstances in London; but with the
knowledge that the finil constitution of a Teaching University
for the metropolis may be decided within the next few months,
I cannot but feel that London will be happy if it escapes from
the fetters which some of its so-called friends are forging for
learning ; and if, on the other hand, the wise determination of
the Gresham Commissioners to include in the university only
institutions of university rank, can be maintained against the
attacks which will be made upon it.

Lastly, I wish to defend the memory of von Helmholtz from
a possible misconception. Those who cultivate art may per-
haps look upon him as the poet or the master of style look
upon the grammarian, as a mere gerund-grinder, occupied with
the study of the dead materials wnich they alone can use. Of
course Helmholtz was not a great artist in the sense that he was
a great scientific man, but it would be most unfair to picture
him as interested only in the study of laws, and as insensitive to
beauty, as occupied with sound and light, but careless as to
music and painting. I could quote passage after passage from
his works to prove his keen sense of the loveliness as well as of
the order of nature, to show the homage that he paid, and the
freedom he accorded to art. His object was not to lead art
captive to science ; but rather to unite them in an alliance of
mutual confidence and support.

" The horizons of physics, philo;ophy, and art have," he said,
" been too widely separated, and, as a consequence, the lan-
guage, the methods, and the aims of any one of these studies
presents a certain amount of difficulty for the student of any
other of them." To smooth away these difficulties, to bridge
over the separating gulf, to supply the common language, were
the objects of the life-work of von Helmholtz. It was a noble
ideal, nobly pursued, and crowned with as much success as
could reward the efforts of one man. It is an ideal akin to that
which dominates this Institution, where science, literature, and
art are all heard in turns.

If it is possible to sum up in a sentence the teaching of
von Helmholtz, and the work of his life, it is that, in spite of
the apparent diversities between science and science, between
science, philosophy, ani art, there is a fundamental unity, and
that the future is for thoie who detect, amid the seeming
discords of the schools, the true harmony which underlies and
dominates them all.

ELECTRIFICATION OF AIR AND OTHER
GASES.^

§ I. AT the meeting of the British .Vssociation in Oxford in
■'*■ August 1X94, a communication was given to Sec-
tion A, entitled "Preliminary Experiments to find if Subtrac-
tion of Waterfrom Air Electrifies it." These experiments were
performed during July of 1894, and were a continuation of
experiments which were commenced in the Physical Laboratory
of the University of Glasgow in December of 1S6S with the
same object, but which were then, for various reasons, dis-
continued before any decisive result had been obtained.

1 A Paper liyLord K<^Ivin. P.R S., Magnus Maclean, and Alexander
Gall, read at the Royal Soc.cly on February 21.

496

NATURE

[March 21, 1S95

§ 2. A glass U-tube with vertical branches (Fig. I), each
18 inches long and about i-inch bore, with the upper 8 inches
of one of the branches carefully coated outside and inside with
clean shellac varnish, was held fixed by an uninsulated support
attached to the upper end of this branch. The other branch
was filled with little fragments of pumice soaked in strong
sulphuric acid or in water, and a fine platinum wire, wiih
one end touching the pumice, connected it to the insulated
electrode of a quadrant electrometer. A metal can, M, large
enough to surround both branches of the U-tube without
touching either, was placed so as to guard the tube from electric
infiuences of surrounding bodies, the most disturbing of which
is liable to be the woollen cloth sleeves of the experimenters or
observers moving in the neighbourhood. This metal can was
kept in metallic connection with the outside metal case of the

calcium in lump:, not specially dried, gave no effect in the
straight tube ; but if previously heated to lSo° or 200° and put
into the straight tube when still hot, it gave an enormous positive
electrification immediately on the commencement of blowing.
Strong positive electrification was obtained a second time, by
discharging the electrometer to zero, re-insulating, and re-
commencing the blowing. But after discharging a second time,
re-insulating, and re commencing the blowing, no further elec-
trification was found.

§ 4. In continuation of these experiments on September 25,
the arrangement represented in Fig. 2 was set up. The outer
metallic guard-vessel, M, was kept connected by a wire lo the
case, and to one pairof quadrants of a quadrant electrometer, E.
The water in the inner glass jar. A, was connected by a pla-
tinum wire to the oilier pair of quadrants of the electrometer.

quadrant electrometer. The length of the exposed platinum
wire between the U-tube and the electrometer was so short that
it did not need a metal screen to guard it against irregular in-
fluences. An india rubber tube from an ordinary blow-pipe
bellows was connected to the uninsulated end of the U-tube.
Air was blown through it steadily for nearly an hour. With the
pumice soaked in strong sulphuric acid in the other branch, the
electrometer reading rose in the course of three-quarters of
an hour to about g volts positive. When (he pumice was moist-
tened :vit/t water, instead of sulphuric cuid, no such effect ivas
observed. The result of the first experiment proves decisively
that the passage of the air through the U-lube gave positive
electricity to the sulphuric acid, and therefore sent away the
dried air with negative electricity. A corresponding experi-
ment with fragment^ of pure chloride of calcium instead of
pumice in sulphuric acid, gave a similar result. In repetition

Fig. 3.

To have this inner jar well insulated, it was supported on a
block of parailin ; and the other end of the glass tube dipping
into the water was fitted into one end of a lube of paraffin, to
the other end of which was fitted a tube for ingress of air, from
bellows, as shown in the figure. The insulation of this arrange-
ment was found to be good. When air w.is blown through the
water it was found that the jar containing the water became
positively electrified.

§ 5. To prevent splashing of water out of the jar, a paper
cover was put on its mouth, or the jar was tilted, as shown in
I" 'g- 3i so that the bubbles broke against the inside of the jar.
In three experiments thus made, the same electrification was
still found, amounting to about 6 volts positive in a quarter of
an hour.

§ 6. As the jar was in every experiment positively electrified,

J_

/

--P

\

'■

A

-

■-r#-'

\

of the experiments, however, it was noticed that the strong
positive electrification of the U-tube seemed to commence some-
what suddenly when a gurgling sound — due lo the bubbling of
air through free liquid, whether sulphuric acid or chloride of
calcium solution in the bend of the U-tube — began lo be heard.
It ha^ iince been ascertained that it was because no linuid ac-
cumulated in the botlom of the U-tube that no electric effect
was found when the pumice was moivtened with pure water.

% 3. .Arrangements were made to prevent any bubbling of the
.Vir through liquid, by using a straight lube insle.id of a U-tube.
In a large number of cxperimmts with pumice, moistened with
pure sulphuric acid in the straight lube, ond air blown through
for about half an hour, no definite electrification was obtained.
In this Mtaight lube, as formerly with (he U lube, pumice
moistened wilh pure water gave no electrification. Chloride ol

NO. 1325, VOL. 51]

Fin. ^.

llie air, if unclcctrified ' when entering it, must have been
negatively electrified when leaving it.

S 7. To lest if the air was negatively electrified after
bubbling, on October II the apparatus- shown in Fig. 4 was
set up. The apparatus consists of a large sheet iron vat, V v,
125 cm. in diameter and yocm. in height, iiwerled on a large
wooden tray lined with lead, anil supported by three blocks of
wood, liy filling the Iray with water llie air is confined in
the val.

c ( is a mclal screen kept metallically connected with the

I Air wan similarly blown from bellows into llie val (tee I 7)willioul snT
biilihlinK, anil no ekclrificition w.u observed. .

-' The val, the wiilerdropi>er, and ihc elcclromclcr are Ihe same M in IM
apparalix. described in the I'lmecdingi of ihe Rojal Society, vol. 56, year
1894, " Klettrilicalion of Air," by Ixjrd Kelvin .ind Magnus Macle.-in.

March 21, 1895]

NA TURE

407

case of the electrometer, and with the vat. It surrounds both
the electrometer and the water-dropper, to prevent any external

varying electrifications from
vitiating the proper results of
our experiments.

This screening of the elec- '
trometer is absolutely neces-
sary when it is used with high
sensibility (70 scale divisions
per volt in our experimenis)
in a laboratory or other place
where various other electric >
experiments may simultane- ^
ously be goingon. Four years Jf
ago the electrometer, the vat, °
and the water-dropper, were ■
set up on the class-room table ^
"vithotit a metal screen. When ^
the deflection indicated about
4 volts negative {see § S), the 2
negative lead of Lord Kelvin's
house electric-light circuit,
which passes through the
class-room, was joined to
earth. This changed the de- 3
flection of the electrometer
suddenly by I volt in the posi-
tive direction. When the
positive lead was "earthed,"
the deflection was changed 4
suddenly by 6 volts in the
negative direction. Putting
on sixteen 8 e.p. electric
lamps, eight on each side of
the class-room, changed the 5
deflection by two-thirds of a
volt in the negative direction.
§ 8. In experimenting with
the same apparatus ' in 1890, it

1 Phil. Mag. August, 1890, "
*' Electrification of Air by a Water
Jet," by ^Iaclean and Goto.

NO. 1325, VOL. 51]

CuRvas 6 AXD 7.

was found that the water jet gave negative electricity to the
ordinary air of the laboratory enclosed in the vat. The
present experimenis fully confirm this
result, showing a gradual negative electri-
fication of the enclosed mass of air rising
to about S volts in an hour, once every
day for the first few days. For twenty-
eight days after the vat was set up, in
October 1894, fifteen observations of an
hour each were taken to find the effect of
the water-dropper, with no other disturb-
ing influence on the unchanged volume of
air inside the vat. These experiments
verify the conclusion (Phil. Ma^., August
1890) that the more the air inside the vat
became free of dust, the less became the
rate at which the air was negatively elec-
trified by the water-dropper.

§ 9. On October 15 last the vat was lifted
from the tray to remove some obstruction
in the nozzle of the water-dropper, which
was not then flowing freely. Curve (6) was
obtained that afternoon. The air in the
vat was the ordinary air of the laboratory,
and the curve shows the effect of the
water-dropper alone in electrifying the air
negatively. For the next two days the
water dropper was kept running continu-
ously for about eight hours each day, to
wash the dust out of the air, and on October
18 curve (7) was obtained. It shows a much
less rate of negative electrification than
curve (6). In the experiments of summer
1890 an aspirator was used to draw the air
from the vat, and a tube full of cotton-wool
was used to filter the air drawn into
the vat.

Curves (i) to (5) are reproduced from
the Philosophical Magazine, and they
show that the more the air becomes free
from dust the less is the rate at which the

CORrES I TO 5.

4q8

NATURE

[March 21, 1895

water-dropper electrifies. Thus curve (I) was obtained from
the ordinal)' air of the laboratory in the vai, and curve (2) after
the aspirator was working for some time. In this curve the
water-dropper ilsf If was running for seme time before the first
observation was taken. The other curves were obtained after
ftirther continuous working of the aspira'or.

After curve (4) was obtained the aspirator was worked
contioDously for iwenly-five hours, and then curve (5) was
obtained.

§ 10. At the end of twenty-three days of October and
November 1894 (;:§ S, 9, above), when the air inside the vat
must have been fan ly free from dust, and when the water dropper
of itself was giving little negative electrification, we bubbled air
into it by a forked tube, one end of which was connected to a
bellows, and three other open ends were below the water inside
the vat. In five experiments thus made^ — two on November 7,
two on November S, and one on December 17, an average
negative electrification of 5 volts in twelve minutes was
obtained.

S II. We now arranged a U-t»be with pure water in it
(Fig. 4) outside the vat. Air from the bellows bubbled

5 10 J5 20 1

Minutes

3

A

HI

\

\

5
6

7

1

1)

■\

■•5

^

■

>

v

X

\

1

WATER -DRO

•PER FILLED ATX \

through the water in this U, and was carried thence by a
block-tin pipe into the vat without any further bubbling.
Observations by the f|uadrant electrometer, while the water-
dropper nas running and the bellows worked, gave us measure-
menU of the varying stale of the electrification of the air in
the vat. The average of fifteen experiments gave a negative
electrification of the air in the vat of SJ volts in 25 minutes.
The rale at which the air was blo-*n in in these experiments
was such as to displace the entire' volume of air in the vat in
half an hour.

% 12. Curve (8) shows the rate of electrification of air, in
one of the fifteen experiments, when thus bubbled through the
water in the U-lube and then admitted into the val.

§ 13. Two (J-tubci, in series, wiih water in each, did not
iccm to give a perceptibly cumulative effect.

S 14. The effect of one or more wire gauze strainers between
the U-iube and the vat, or between the U-tube and the bellows,
wai next test. d. The gauzes were placed between short lengths
of lead tul«, which were held together by a rubl.cr tube slipped
over therri. The arrangement is shown by longitudinal and
cross sections in I-'ig. 5. Twelve wire gauzes, with or without

cotton-wool between them, placed between the bellows and the
U-tube, did rot prevent the subsequent electrification by bub-
bling of the air thus filtered. But when placed between the
U-tube and the vat they almost entirely di.-electrified the air, even
without the cotton-wool, and still more decidedly when cotton-
wool was loosely packed between the wire gauzes. A single
wire-gauze strainer produced but little of dis-elecirifying effect.
§ 15. The interpretation of these experiments is complicated,
and the lime required for each is lengthened, on account of the
large mass of air in the vat to start with, whether uncharged 01
retaining electricity from previous expeiimenis, and also on
account of the effect of the water-dropper itself. Hence, in
our later experiments, we fell b.ick on the arrangement shown
in Fig. 2, by which we test the electrification of the liquid, and
not directly that of the gas blown through it.
. § 16. In our first experiment with this apparatus the
( amount of the electrification did not seem much affected
when a paper cover was put on the beaker, or when we
tilted the beaker as shown in Pig. 3. We now made a
large number of tests with dilTcrent covers and screens
(chiefly of sheet copper or sheet zinc, or brass wire gauze) at
difi^erent heights above the liquids, .ind we concluded that, if the
screens are not within a centimetre and a half of the liquid sur-
f.ice, they Jo not directly affect the magnitude of the electrifica-
tion obtained. In nearly all of the subsequent experiments a hori-
zontal circular screen of thin sheet copper, leaving an air space
of about 3 mm. all round between its edge and the inner sur-
face of the jar, about 3 cm. above the liiiuid surface, was used
to prevent spherules of the liquid from being tossed out of the
jar by the bubbling.

§ 17. In the following short summary of our results the dura-
tion of each experiment was ten minutes. The efltect of blowing
air through water and other liquids is summarised in !;§ 18 to

NO. 1325. VOL. 51]

Lead-.

India Rubber-

Fio. 5.

27, and of blowing other gases than air through waterjin §§ 28
to 31.

§ 18. The jar contained 200 c.c. of the Glasgow town-supply
water (from Loch Katrine). A mean of seventeen experiments
showed an electrification of the jar to four volts positive when
air was blown through it for ten minutes.

§ 19. A solution of zinc sulphate of different strengths was
now used instead of the pure water. Three experiments, with 150
c.c. of water containing one drop of a saturated solution of the
zinc sulphate, gave half the positive electiihcation that would,
under similar circumstances, have been obtained from water
only. With live drops no definite electrification was olitained.
\\ iih greater proportions of the zinc sulphate solution up to
saturation (twenty-four experiments altogether) the electrifica-
tion was on the average slightly negative.

§ 20. Twelve experiments were then made to test the effect of
adding a solution of ammonia to the water. One drop reduced
the electrification to one-half; two drops brought it down to
<pne-quartcr. With larger proportions of ammonia than this,
up to a saturated solution, we found a veiy slight positive
electrification, never amounting to more than a small fraction of
a volt, and therefore negligible in the circumstances.

§ 21. Seven experiments with sulphuric acid of different
strengths all showed small /u-ti/rr'^ electrification, the amount
gradually decreasing from \ volt, in ten minutes, with o'5 per
cent, acid in water to ,',.. volt, in the same time, with acid o£
full strengih.

Seven experiments with hydrochloric acid solution of different
strengths all showed a small tiCj;alhe elcctrificaiion, the amount
gradually increasing from \ volt, in ten minutes, with \ per
cent, acid solution in water to ij volts, in the same time, with
acid solution of full strength.

Nine experiments with calcium chloride solution were made.
A saturated solution and a solution diluted to 75 per cent, of
full strength gave no result ; but solutions of gradually
diminished strength, from 50 per cent, down to ,'„ per cent.,

March 21, 1895]

NATURE

499

volt,

ten

!

Per cent, of

saturated solution of

salt in water.

(a) 0004

(b) 0'02

(r) o-i

(d) o-S

(e\ 20

(/)4-o

showed a negative electrification from fully
minutes, down to ,V volt.

Additions of very small quantities of washing soda to water
greatly reduce the positive electrification obtained.

Loch Katrine water, supersaturated with carbonic acid, and
placed in the insulated jar, showed, when air was bubbled
through it for ten minutes, a negative electrification of \ volt.

§ 22. Ten drops of paraffin oil added to water reduced the
electrification to about half of that obtained from water only.
Thirty drops reduced it to about a tenth, which, as it amounted
tu only o'4 volt during the time of the experiment is negligible.

S 23. Ten drops ol benzene reduced the electrit'ication to
half, and thirty drops to about a third of that taken by pure
water.

§ 24. A saturated solution of granulated phenol (carbolic
acid) was made, and small portions of it added to the water in
thejar. Several experiments showed no diminution in theelectii-
ficationas long as the quantity of the phenol solution present in
the water was under lo per cent. With 25 per cent, the
electrification was reduced to a third. With strengths greater
than this up to saturation the electrification was reduced to
one-sixth.

ij 25. A saturated solution of common salt was prepared. Blow-
ing air through 200 c.c. of water containing the quantit'ts of the
^alt solution mentioned, gave us in ten minutes the following
electrifications : — ■

Volts
positive.
2-4
\-2
06
04
015

o-o

§ 26.' Several experiments showed that with 200 c.c. of water
containing not more than ten drops of absolute alcohol,
practically the same amount of positive electrification (4 volts in
ten minutes) is obtained as if pure water were used. With filty
drops less than 2 volis were got, and with 100 drops less than
I volt. 25 and 50 per cent, alcohol in the water gave very
small and hence negligible positive electrification.

§ 27. One drop of saturated solution of copper sulphate in
:;oo c.c. of water showed one volt positive in ten minutes.
With \ per cent, of it in the water, the electrification was
reduced to a fraction of a volt positive. With greater pro-
portions of copper sulphate present, up to saturation, slightly
negative electrifications were obtained, but never amounting to
more than about one-tenth of a volt, and hence negligitile.

§ 2S. On blowing carbonic acid gas from a cylinder obtained
from the Scotch and Irish Oxygen Company, through pure
water in the glass jar, the water became electrified to %\ v^olts
positive in ten minutes. Blowing the breath through water
gave an electrification of 3 volts positive in the same lime : this
diminished result is doubtless due chiefly to the diminished rate
of bubbling.

§ 29. The blowing of oxygen from a cylinder, obtained from
tile Oxygen Company, through water, gave as a mean of four
experiments a positive electrification to the water of half a volt
in ten minutes. When continued for fifty-five minutes, it gave
the very decided result of 5 volts positive.

S 30. Hydrogen prepared from zinc and dilute sulphuric acid
was passed into a large metal gas-holder ; and was parsed on
from this to bubble through the water in the insulated jar. In
two experiments this wasdone immediately after the preparation
of the hydrogen ; in another it was done after the hydrogen
had remained eighteen hours in the gas-holder. In each of the
three experiments the water was electrified to 2 volts positive in
ten minutes.

When the hydrogen was allowed to pass direct throujh a
tube from the Wolffe's bottle where it was generated, to bubble
in the insulated jar, the magnitude of the effect obtained was
very much larger. In one case a mixture of muriatic acid and
sulphuric acid and water was used, and the reading went ofl^the
scale positive in thirty seconds (more than 10 volts). In
other two experiments with dilute sulphuric acid and zinc in the
Wolfle's bottle, theelectrificationsobtained were 6 volts positive
in seven minutes, and 7 '3 volts positive in thirteen minutes, in
the last of which the hydrogen was allowed to bubble through

NO. 1325, VOL. 51"!

caustic potash contained in a small bottle between the Wolflfe's
bottle and the insulated jar.

The hydrogen was next generated in the insulated jar itself,
the tube for ingre-s of air used in the ordinary experiments
being taken away. 200 c.c. of pure water, along with some
granulated zinc, was put into the jar. Then some pure sul-
phuric acid was added, and electrometer readings were taken.
In two experiments with no screen in the jar (i; 16) the read-
ing went off the scale nti;ati-je (i) in two minutes and (2) in
four minutes (more than 9 volts in each case). In another
experiment in other respects the same, hut with a cooper ^cieen
7 cm. above the surface of the liquid, the electrification showed
2 volts negative in two minutes, then came back to zero in five
minutes, and in the next six minutes went 4 volts positive.
The jar and pair of quadrants connected with it were then
metallically connected with the outer case of the electrometer
for a few seconds, and reinsulated ; in five minutes the reading
went up to 2 volts pasitri-e. A little more sulphuric acid was
added to thejar, which was disinsulated for a shirt time and
reinsulated ; the reading went up to 7 volts positive in four
minutes. The jar was again disinsulated for a few seconds and
reinsulated ; the reading went up in four and a half minutes to
6J vnUs/iositive.

§ 31. Coal-gas, bubbled through water in the insulated jar,
gave I '4 volts positive in ten minutes.

§ 32. In the ordinary experiment of bubbling air through a
small quantity of wa'er in the bottom of the jar it was noticed
that the electrification did not commence to be perceptible
generally till about the end of the first minute ; and that it went
on augmenting perceptibly for a minute or more after the bubbling
was stopped. The following experiment was therefore tried
several times. One of us stood leaning over thejar, with the head
about 10 inches above it, and the mouth so partly closed that
breathing was effected sideways ; another blew the bellows, and
another took the readings of the electrometer. After bubbling
had been going on for some minutes, and the readings were
rising gradually (4 volts per ten minutes, as in § 18), blowing
was stopped. As soon as the bubbling ceased, the first-men-
tioned observer, without moving his head or his body (see !i 7,
regarding the necessity to have the electrometer screened from
outside influences), blew into ihe jar to displace the negatively
electrified air in it. In every ca^e the electrometer reading
showed instantly a small rise in the positive direction.

In the carrying out of these experiments we have received
much valuable help from Mr. Walter Stewart and Mr. Patrick
Hamilton.

§ 33. The very interesting experiments describe! by Lenard,
in his paper on the Electricity of Waterfalls ( WieJemann" s
Ainialeii, 1892, vol. 46, pp. 5S4-636). anf by Prof. J. J.
Thomson, on the Electricity of Drops (Phil. ji/a^. April 1894,
vol. 37, pp. 341-358), show phenomena depending, no doubt,
on the properties of matter, to which we must look for ex-
planation of the electrical effects of bubbling described in our
present communication, and of the electrification of air by
drops of water falling through it, to which we have referred
as having been found in previous experiments which were com-
menced in 1890 for the investigation of the passage of electrified
air through tubes. ^

UNIVERSITY AND EDUCATIONAL
INTELLIGENCE.

Cambridge. — The Isaac Newton Studentship in Astronomy
has been awarded to Mr. S. S. Hough, Scholar of St. John's
College, Third Wrangler in 1892, and Smith's Prizeman in
1894.

Mr. C. T iHeycock, Lecturer in Chemistry at King's College,
First Class in the Natural Sciences Tripos 1889 has been
elected to a Fellowship.

The discussion by the Senate of the proposals for the
encouragement of Advanced Study and Research, by the
admission under special conditions of Graduates of other
Universities, wns on the whole favourable to the scheme.
There seems little doubt that the preliminary resolutions on the
subject will be passed early next term.

Mr. Arthur R. Hinks, of Trinity College, has been appointed
Second Assistant at the Observatory for five years, from July
I, 1895.

' '_' Electrification of Air by a Water let." By M-tgnus Maclean and
Makita Goto, Phil .Mag. August 1890, vol.30, pp. 148-152.

500

NA TURE

[March 21, 1895

Sir John Lvebock has been elected President of the
London Society for the Extension of University Teaching, in
succession to Mr. Goschen, M.P., resigned.

Mr. Gilbert R. Redor.we has been appointed Chief
Senior Inspector of Schools and Classes under the Science and
Art Departmen:, and Mr. T. B. Shaw, Inspector of the North-
western District, has been promoted to a Senior Inspector-
ship.

SCIENTIFIC SERIALS.

We have received two recently issued parts of the Journal of

the Asiatic Society of Bmgal iyoi. Ixiii. part ii. Nos. I and 3)
containing, inter alia, an important paper by Mr. Lionel dc
Niccville (the author of the admirabk- book on the butterflies
of India, Ceylon, and Burma, now approaching completion),
on new and littlc-known butterflies from the Indo-Malayan
region, illustrated by five excellent coloured plitei, representing
species belonging to most of the principal families represented
in the district. Among the species figured is a handsome new
species of Stichophthalma (5. sparta) from Manipur, allied to
the well-known Chinese 5'. howqua, of Westwood, belonging
to a genus allied to the great blue Morphos of South America,
and not inferior to some of them in sire ; a gynandomorphou.s
specimen of the common, but very remarkable, Indian
Fritillary, Argynnis niphe, L., the female of which mimics the
abundant, highly-protected, and much-imitated Danatis
ihrysipp%ti, L. ; several species of Laxita, Butler, a beautiful
genus allied to our Duke of Burgundy Fritillary, but much
larger, and with rounded brown wings, generally suffused with
crimson on the fore wings, and marked with metallic blue spots
beneath ; three species of Papilio, two of which mimic species
of the widely-removed sub-family Euplocina ; and many other
interesting species. Several genera, as well ns a large number
of species, are described as new, and much fresh information
is given relative to species already known. Several very useful
lists and tables are also included in the paper, relative to the
species of Daphla, allied to D. teuta, Doubleday and Ilewit-
son, and those of the genera Gcrydus, Boisduval, Lcgania,
Distant, &c. When we look at the number of important books
and papers that are now constantly issuing from the press on
the butterflies of various parts of the British East Indies, it
seems strange to remember that thirty years ago almost nothing
had been published specially on the subject, except Ilorsfield
and Moore's Catalogue of the Lepidoptera in the East India
Company's Museum, and Westwood's "Cabinet of Oriental
Entomology."

Mtinoirs {Trudy) of the St. Petersburg; Society of Naturalists,
vol. xxiv. part I, Zoology and Physiology. — Notes on birds
found in the Mediobor Mountains of Podolia, by I. D.
Mikhalovslcy. Seventy-two species are mentioned. — On the
structures and reactions of the cells of the digestive tube
of the pupa: of il/aiffl CrjanV zomiloriir, by N. Kholin, with
one plate. — The Natural History Museum of Great Britain,
and other zoological institutions of West Europe, by A.
Y.-ischenko. — Report on the cruise of the Nayczdnil: in
the .Arctic Ocean in 1S93, ^y ^'- Knipovitch. Leaving
Rcval, the cruiser visited the Murman coast, the Dvina and
Onega l>ays of the White Sea, and the west coast of Novaya
Zeailya, entering the Matochkin Strait and the Yugorskiy Shar.
No less than eighty successful dredgings, down to depths of 190
fathoms, as well as measurements of temperature, were made.
The author's remarks on the diflerences of colour and density of
the iilue Gulf Stream water, which is easily traced along the
Murman coast, and the more so along the coast of Nov.iya Zcmlya,
are especially interesting. The colour and the density better
delineate the south-cast limits of the Gulf Stream current than the
HitTcrenccs of temperature which are affected in both the Gulf
ST' im and the cold current by various local causes. In the
*■ ,ys of the While Sea, M. Knipovitch found in the bottom
mud, which has temperatures of one or two degrees below zero,
the YolJia arcti,a, characteristic, as is known, of the Glacial
period deposits and the Arctic Seas ; while the same has never
t>ecn found in the Arctic Ocean off the .Murman coast, nor in
■'ic citern parts of the IJarents's .Sea. — Report on the zoological
. utions of West Europe, by Piof. K. Sainte Hilaire. — In the
J'iv:eedings we notice a very interesting report, by A. .\.
Binilia, on the part played by the phagocytes in the sexual

NO. 1325, VOL. 51]

processes with the GaleoJes, and A. K. Trotsin's report on his
zoological journey to the Transcaspian region and Russian
Turkestan

The Meteorolo^sche Zeitsihrift for January contains a care-
ful discussion of the rainfall of the Sandwich Islands, by Dr.
J. Hann, based chiefly on observations supplied by the Director
of the Weather Serviceat Honolulu. The amount of th; rainfall
is subject to great fluctuations. At Ililea, Kau (on the south
side of Hawaii), 44'5 inches fell in 1SS6, and of this amount
51 per cent, fell in November. In 18S9 the annual fall was
only I3'9 inches, or about half as much as in November 1SS6.
\K Honolulu the avera:;e annual fall is 40 inches. The heaviest
falls occur on the windward side of the largeU of the islands,
that is, on the north-east of Hawaii, and the smallest falls
occur on the southern part of Oahu, and the south- west of Miui.
The wettest period in almost all the islands is from November
to March. The principal exception to this is on the leeward
side of the mountains of Hawaii, where more rain falls in
summer than in winter.

SOCIETIES AND ACADEMIES.

London

Physical Society, March S.— Mr. Walter Baily, Vice-
President, in the chair. — Mr. Naber exhibited, and shortly
described, a new form of gas voltameter. The chief advantages
claimed for this instrument are th it either the oxygen or the
hydrogen can be collected separately, and that the level of the
liquid inside and outside the burette can be made the same;
thus no correction has to be applied to the volume of the gas
on this account. Variations in the temperature and barometric
pressure are allowed for by reading an air thermometer which
is fixed alongside the burette. The inventor considers that this
instrument will compare favourably in accuracy with the copper
and silver voltameters now in general use. Prof. S. P. Thomp-
son considered that now so much care h.ad been bestowed on
the design of a gas voltameter, this instrument might come into
more general use than heretofore. — Dr. Johnstone Stoney,
F.K.S., exhibited (i) the local heliost.it, (2) .an improvement
in siderostats. By a local heliostat the author means one which
can only be used in places the latitudes of which differ slightly
from that of the place for which the instrument was specially
constructed. The limits within whicli the instrument works
with suflicient accuracy for ordinary spectroscopic work, are such
that one instrument can be used in any place in the British Isles.
The heliostat exhibited was a modification of one previously
described by the author, which is now in very general use, and
it is capaUTe of sending a reflected ray in any direction in, or
nearly iif, a horizontal plane. In the new instrument the pen-
dulum clock previously used to supply the motive power, is re-
placed by a balance-wheel clock ; this ch.ange decreases the
cost of the instrument, while it adds to its portability. A tangent
screw, worked by a long rod, supplies a slow motion for adjust-
ing the position of the reflected beam, and is of use when
examining the spectra of the solar prominences, &c. The
instrument is adjusted in the meridian by means of a gnomon
and horizontal divided circle which form a sun-dial. This
divided circle is so arranged that it is always horizontal when
the polar axis is in adjustment, and can therefore be used what-
ever the latitude of the station at which the observations are
being made. In connection with the use of a heliostat in con-
junction with a spectroscope, the author recommends, when
using a grating, the introduction of a large glass prism between
the heliostat and the slit of the spectrometer. An impure
spectrum is thus formed on the slit, and by moving the slit to
the part of this spectrum corresponding to light of the wave-
length under observation, the difficulties due to the overlapping
of the spectra may in a great measure be overcome. After men-
tioning that the great diflicully in designing a siderostat
which should work with "astronomical accuracy," is to
get a form of sliding motion quite free from back-lash,
and which will move perfectly regularly. Dr. Stoney ex-
hibited a model of a form of mechanism for obtaining such 1
motion which he had devised. The principle on which the
instrument depends is that, if you have a point fixed to a circle
which rolls on the inside of another circle of double the
diameter, this point will describe a straight line. The smaller
disc does not, in the model exhibited, roll directly on the larger

March 21, 1895J

NATURE

501

disc, but an idle wheel is introduced which rolls on the outside
of both the discs. Slip is avoided by placing steel bands be-
tween the idle wheel and the discs, one end of each of Ihc- two
bands being fixed to Ihe circumference of the idle wheel, while
the other ends are fixed, one to the circumference of each of
the discs. Back-lash is prevented by means of a spiral spring
attached to a point on the smaller disc ; this point being so
chosen that it moves nearly perpendicular to the direction in
which the spring acts. Hence the spring is always stretched
to nearly the same amount, and no extra strain is brought to
bear on the driving-clock in different positions of the instru-
ment. Prof. S. P. Thompson considered that the best method
to employ when using sunlight was to incline the telescope,
&c., parallel to ihe polar axis, under which circumstance the
mirror of the heliostat need only rotate about a vertical axis. —
A paper, on a simple form of harmonic analyser, was read by
Mr. G. U. Yule. At a former meeting of the Society, Prof.
Henrici showed a form of analyser in which the paper on
which the curve is traced was given a to-and-fro movement, a
planimeter being used as an integrator. The author being
struck with the advantages of the use of a planimeter, both as
regards cheapness and simflicity, has devised another form of
analyser in which a planimeter is used. The principle on which
this instrument works is as follows : — Suppose we have a straight
line (X X) which can move parallel to the base line of the given
curve, so (hat every point in this line describes a perpendicular
to the base ; further, suppose that a disc, the circumference of
which is some aliquot part of the base of the curve, say 2ijn
where 2 /is the base length, is capable of rolling on the line
(X X) without slip. If the centre of the disc is brought over the
initial point of the curve, and any point (D) at a distance r from
the centre on a horizontal diameter is marked, then if the
centre of the disc is made to describe the curve which is to be
analysed, the area of the curve described by the point D is
given by the equation

R, = a + cos«7r — '^ / ys\ati9dx,
I \ - I

where o is the area of the curve to be analysed. Similarly, if
the point D is taken originally on a vertical diameter, the
area of the curve traced out is

R., = a + cos tm ^^ / y cos ni dx.
I J -I
In any practical case it is convenient to take >" some multiple of
l/ir units of length, sayao, then the above equations become

Rj = o + cos « Tt. 10 ». B„
and

R^. = a + cos « v. ion. A„

where B„ and A„ are the coefficients of sin «9 and cos k9 in
the Fourier series expressing the equation to the curve. The
areas of the curves traced out by the point D (R, and Ro) are
obtained by allowing the tracing-point on an Amsler planimeter
to rest in a small conical hole at D. The line X X is the edge
of a rolling parallel ruler which has a rack cut along it. A
series of toothed wheels give the coefficients of the different
terms in the series. In the instrument exhibited there were
wheels to give the first four terms, but the author said it was
possible to work with wheels which gave the sixth term. The
above analyser was the outcome of a simple step-by-step in-
tegrator which the author had devised. In this case the base
line of the curve having been divided into a number of equal
parts, then, by means of a scale of sines attached to the instru-
ment, the tracing-point of a planimeter is set at a point whose
abscissa is sin «9, while it is moved parallel to the axis of y
through a distance hy corresponding to one of the elements
into which the base was divided. Prof. Henrici said he had at
one time considered the question of constructing an analyser
which should employ a planimeter as the integrator, and he was
particularly pleased with the instruments exhibited. Since the
area required was the difference between the areaof the original
curve, which is traced out by the centre of the disc (K), and the
curve traced out by the point D, and since this area is really the
area swept out by the straight line K D, if we attach an in-
tegr.ating wheel to the disc, with its axle parallel to K D, Ihe
icquired area can be directly obtained from the reading on this
wheel. In addition, if a second integratingwheel were fixed to
the disc, with its axle perpendicular to K D, the coefficients of
cos «fl and sin nO could both be obtained by going round the
curve once. The instrument devised by Mr. Yule was practically

NO.

«325, VOL. 51]

the inverse of one :he [(Prof. Henrici) had invented. Dr.
Burton pointed out some incorrect signs in the proof givea ;
these, however, do not affect the final expressions obtained.
Mr. Inwards .suggested that errors due to back-lash might be
avoided by using either a double wheel or a double rack, so
that by means of a spring each side of the teeth which were
engaged might be in contact at the same time. — Prof. Minchin
gave a short account of a paper by Mr. H. N. Allen, entitled
"The Energy Movements in the Sledium Separating Electri-
fied or Gravitating Particles. " The object of the paper is to trace
out the equipotential surfaces and lines of flow for two electrified
points or gravitating Iparticles, and then to consider the paths
along which the " energy cells " move when the charged points
or gravitating particles either move towards or away from one
another. By energy cell the author understands the small
volume of the dielectric bounded by the walls of a tube of
force, and by two neighbouring equipotential surfaces, which
can be looked upon as containing a certain definite amount of
energy. The author gives two figures showing the paths of the
energy cells : (i) when the charged particles come together and
meet ; (2) when they separate and move off to infinity in
opposite directions. Using Maxwell's expression for the pres-
sure along the lines of force, and the equal tension at right
angles required by his theory to account for the attraction
exerted by the sun on the earth, the author has calculated the
energy density in the medium at the surface of the sun. The
value obtained is l6-horse power-hours per c.c. Hence he
concludes that, at a distance from all gravitating bodies, a c.c.
of ether contains at least this amount of energy. Prof.
Minchin showed how, by the use of polar coordinates the ex-
pressions given by the author could be simplified. He also
gave a graphical method of obtaining the equipotential sur-
faces for any configuration having given those for any other
configuration. He pointed out that by a similar line of reason-
ing to that used by the author, the energy per c.c of the
maJium at the surface of Arcturus must be 8100 times as great
as at the surface of the sun, so that the minor limit given
above by the author must be multiplied by 8100 at least.

Entomological Society, March 6. — Prof. Raphael
Meldola, F.R.S , President, in the chair — Mr. B. G. Nevin-
son exhibited a long series of Heliothis pcUigera. He stated
that the specimens were bred from larvae found on the Dorset-
shire coast during July 1894, feeding on the flowers of Ononis
arvtnsis, which were extremely luxuriant. A few also were
taken on Hyoscyamus iiiger. He added, that all the larva: went
down by the end of July. The first emergence took place on
August 20, and they continued coming out at the rate of about
five a day, through the rest of that month and September; only
five emerged in October, and the last one appeared on Novem-
ber It. Mr. G. T. Bethune- Baker, Mr. Eustace Bankes,
Mr. B. A. Bower, the Rev. Seymour St. John, and Mr.
H. Goss made remarks on the habits and distribution of
the species in England. — Mr. Bower exhibited a variable series
of Seofaria basislrigalis, Knaggs, showing light, intermediate
and dark forms, taken at Bexley, Kent, from June 12 to July
7, 1891-94. He said the species appeared to be poorly repre-
sented in collections, and when present was almost invariably
misnamed. Mr. Bankes commented on the rarity of the species,
and said the specimens exhibited formed the most interesting
collection of it and its varieties which he had ever seen. — Lord
Walsingham, F. R.S. , exhibited larva; of Promtba ynccasella^
which he received more than four years ago from Colorado, and
which were still living. One specimen of the moth had
emerged two years ago. — Mr. Goss exhibited, for Mr. G. C.
Bignell, a pupa of a Tortrix, with the larval legs, and also a
specimen of a Sawfly, Emphyliis cinctus, L., with eight legs.
Mr. G. H. Verrall and Mr. McLachlan made some remarks on
the latter species, and a? to the insertion of the fourth pair of
legs. — Prof. Meldolaexhibileda wooden bowl from West Africa,
from which, after arrival in this country, a number of beetles
(Dcrmestes vulpinus) bad emerged. Specimens of the latter
were also exhibited. It was not clear to the exhibitor whether
the larvK had fed upon the wood, or had simply excavated the
cavities which were apparent in the interior of the bowl for the
purpose of pupating. Mr. McLachlan, Mr. J. J. Walker, Herr
Jacoby, and Lord Walsingham made some remarks on the
habits of Dermestes. — Mr. Champion read a paper entitled
"On the Heteromerous Coleoplera collected in .\ustralia and
Tasmania by Mr. J. J. Walker, R. N., during the voyage of
H.M.S. Penguin, with descriptions of new genera and species.

502

NA TURE

[March 21, 1895

P»rt ii." Mr. Walker and Mr. Gahan made some observations
on ihe distribution of cerlain of the species desciibed. — Mr.
Roland Trimen, F. R. S., contributed a paper entitled "On ■some
new species of butterflies from tropical and extra-tropical South
Africa." — Mr.G. A. James Rothney contributed a paper entitled
'■ Notes on Indian Ants," and sent for exhibition anumnerof
specimens in illustration of the paper, together with nests of
certain species.

Geological Society, February 20. — Dr. Henry Wood-
ward, F K.S., President, in the chair. — The President
announced lo the Fellows the grievous los< which the Society
hadsuflerd in the decease of its Foreign Secretary, Mr. J. W.
Hulke, F.R.S., President of the Royal College of Surgeons.
He d-eli on the great value of .Mr. Ilulke's work in vcncbratc
palxontology, on hi> long services as a mniber of Council and
an ofTiLcr ol the Society, and on his amiable personal qualities,
which had endeared him to a wide circle of Iriends. He read
the following resolution which the Council had that afternoon
unaniulOu^^ly voted, and communicated to Mis. Huike with the
expression ol their heartfelt sympathy: "That this Council
most deeply deplore the sad loss that the Society and ail iho-e
inlercs ed in palxontology have sustained by the i.ntimely
decease of our Foreign Secretary, Mr. J. W. Hulke, F. R.S.,
whose inve-tigations in various branches of science hdve led to
such valuable icsulls." — Contributions to the pa'Kuniology and
phy>ical geohgy of the We.-l Indies, by Dr. J. W. Gregory.
The cailier pan of the paper was largely concerned with the
corals uf the raised reefs of Baibados, and, on account of the
confa-'ion in the synonymy ol the West Indian corals, the syn-
onymy of the species was given in some detail. A list of the
mollusca of the low-level icefs lollowed. In dlscu>sir.g the age
of the Barbailus rocks, the author staled that the following was
the sequence (in descending order) : —

f

Low level : Pleislo-

Raised coral reefs -' u^k*^"! i t>i-
j High level : PIio-

l. ccne.

I -4 /•«-A/ru/n««.f/«-<ii- 1 Miocene (and possibly
Oceanic series ... ', rw/i/wj-limesionc. j- partly l'liocene)and

( Thalassic marls. j partly Oligocene
Scotland beds ... j Oligocene (probably

( Lower).

— The Whitehaven sandstone series, by J. D. Kendall. The
Whitehaven samlstone, with its associated shal-s, is a purple-
grry depos t sometimes having a thickness of 500 or 600 leel.
The auth'ir gave details of a large number 01 sections of the
series, whicn also contains tliin coal-seams and occasionally
.i/irori/j-liuiestone. — Notes on the genus Miircliisoiiia and its
allies, wi h a revision of the liiiii^h caiboi i crous species, and
descriptions of some new forms, by Miss |. Donald.

Zoological Society, March S-— Sir W. H. Fl .wer,
K.C. B , I- R.S., Pre>Klent, in the chair. — The Secretary read
a report on the additions that had been made to the Society's
menagerie during the month of F'ebruary, and called special
attention lo a fine female giraflTe recently anived from South
Africa. This was believed to be the first example ol the large,
dark-blotched race ever seen alive in liurop , ihe giraffes pre-
viously exiiibiied having belonged to the smaller and paler form
found in Northern Tropical Africa. Tlie Socieiy has also
purcha-eH a pair of Sable Antelopes (//(/»/<)/. r7,«j nigcr) and a
pair of Brindled Gnus (Connochads laurina), all in excellent
condition.— Dr. St. George Mivart, h.R.S., read a paper on
some distinctive structural characters in the hyoid lione in
cerlain parrot". — Mr. A 1). Michael read a paper on a new
Frrshwater M lie lound in Cornwall, and lielongmg to the genus
Thyas, o' which only 'wo species were previously known. It
is pr- po-ed to call it Thyas pelrophiliii. — Mr.G A. B.iulenger,
F.R.S, read a paper "on ihc nurs.ng.haiiits of Iwo Souih-
Amencan Fr g<," and exhibited a aptcimeo of Hyla goeldii with
egg» on Ihe back. He also maHc reiiiaiks on a male kpccimcn
of Phylttbalei trinilath from Venezuela, carrying its tad|ioles
OD its back, in the same way as had previously hecn observed
io ffog» ol the genus Dendrobalts from .Surinam and Krazil.

Royal Meleorolxgical Socieiy, Kebiui y 20. Mr. R.

Inward*, Picsnlint, in ihe chair. — Mr. W. M irrioil gave an
account of the thunderstorm and squall which burst over Lon-
don so suddenly on the morning o( January 2J. It appears

NO 1325, VOL. 51]

that this storm passed acro-s England in a south-soulh-easterly
direction at the rate of about lony-seven miles an hour, being
over Norihumberland at 4 a.m., and reaching the English
Channel by II a.m. Thunder w.is fust heard in the vicinity of
Leeds, and accompanied the stoim in its progress across the
country. One of ihe most reniaikable featuies ol the storm was
ihe sudden increase in the force of the wind, for in London it
rose almost at one bound from nearly a calm to a velocity ol
thiitysix miles an hour. This ?uddcn increase of wind caused
considerable damage, and at Bramley, near Guiloford, twenty-
eight trees were blown down along a track 1S60 yards in length.
— Mr. E. Mawley presented his report on the phenolo^ical
observations lor 1894. Between the third week m March and
the third week in .May plants generally came into blossom in
advance of their usual time, and tow.irds the end of April the
dates of first flowering differed but little (rom those recorded at
the same period in the very forward spring ol 1S93. The
cuckoo made its appearance even earlier th.in in the previous
year. The y>ar 1S94 was a very productive one, and both the
hay and coin crops proved unUsually heavy, but much of the
latter was harvested under very trying conditions as regards
weather. The frosts ol May 21 and 22 entirely destro)ed the
previous prospect of a glorious Iruit season. Indeed, the only
really good crop was that of pears, which were singularly
atiundant throughout neailythe whole ol England. — .Mr. A. B.
Macl'owall read a papier on some gradual weadier changes in
certain mouths at Greenwich and Geneva.

DUBLI.V.

RoyaF Dublin Society, November 21, 1S94.— Prof. W. J.
SoUas, F R. S., in the chair. — The following p.ipers weie read:
On the occurrence o( seiches in Lake Derravaragh, co. West-
meath, by Start-Commander J. R. H. MacFarlane, K.N. This
paper (communicated by Prol. D.J. Cunningham, F.R.S.) is
interesting as being the first record of observations, from the
United Kingdom, of these ph nomenal changes ol the level of
the water in lakes. Ihese singular rhythmic movements, some-
what resembling tidal ebb and flow, were lound occurring in
the Swiss lakes lowaids the close ol the last, and beginning of
the present, century, and many skilful observers devoted con-
siderable time in the endeavour to elucidate the cause or causes ;
but, as yet, no distinct explanation has been given, although it
would appear to have been gencially noticed that they are
accompanied by a low baiometer. It also appears that the
characteristics ol the land, surrounding the observation spot,
influence the time occupied by a complete rise and lall ol the
water, which has been leimed the duration 0/ t/u seiche ; and,
further, that it is probable such duratious are constant for each
observation spot, but the amplitude, or amount of rise above,
ami lall below the level, will acpend on the amount ol influence
exercised in causing the seiche ; this influence being at present
unknown. The observations made at Lake Dcrravaiagh were
necessarily confined lo one spot, no other observers being
available lor synchronous observations at difl'cient stations.
The maximum amplitude recorded was 58 inches, and the
duration of seiche, fairly constant, about 39 minutes.—
A paper was communicated by Sir Charles Cameron, on the
elTeci of poisons and antiseptics on germination, oy Mr. F. H.
Perry Coste. — The Rev. R. Bodkin described an •'automatic ■
image-finder," the object of which is (1) lo show where the
image ol any object placed before any lens must be lormed :
(2) to prove that the image is found there ; (3) 10 hcl|> to ex-
plain the construction ol the various optical instruments in use
such as the microscope, telescope, camera, and projection lamp.

Decenilier 19. — Sir llowaid Grubb, F.R.S., VRc-Piesideni,
in Ihe chair. — I'he (olloiving papers were read: Mr. J..hn K
Wigham described and demontrated a ineihod ol incrcasinj;
the puwer of continuous lighthouse lights. — I'rnl. W. J. Sollos,
F.R.S. , gave a descripiion ol a new lossil, rcsemblii.g annelid
tubes, from the Cambrian of Puck's Rocks, llowih, near
Duhlin. Upon ihi.s fossil the author has bestowed the name
Pucksia Mai,Henryi

Paris.

Academy of Sciences, March II. — M. M.ircy in the
chair.— On aigon, b) M. Berthelot. The iiuthor announces
the C'lmbination ol the new clen ent with benzene vapour under
the influence of the electric discharge, and promises details t<
follow. — Remarks on the cuives defined by a dilTerenlial
equation of the first order, by M. Kmilc Picard. — On the total

March ^Ir, «S95]

NATURE

503

eclipse of the moon of March 1 1, by M. J. Janssen. The im-
portance of ob-ervalions of lunar eclipses by photographic
photometry in connection with the constitution of the higher
regions of our atmosphere is emphasised. — On the losses of
nitrogen carried off by infiltrated water, by M. Schlresing.
The loss of nitrogen by soils in the basin of the Seine through
the elimination of nitric acid in drainage waters is discussed.
In conclusion the author believes such losses not to be very im-
portant ; they are roughly proportional to the richness of the
soil in organic matter, and do not much impoverish already
poor soils. — Analysis of oys'er-shells, by MM. A.. Chatin and
A. Muniz. — Demonstration of a theorem of whole numbers, by
M. de Jonipiieres. If flj. a„, a,, . . . , a,i are >i different whole
number-^, the product n (a) of all these numbers, multiplied by
the product n {«, - Oj) of their diff<;rences by twos, is a multiple
A of the product of « first numbers I, 2, 3, ... , it, multiplied
by the proluct of their dilferences by twos, that is to say, is

equal to A ( I". 2"-'. 3"--. . . . n - 2' . k - i'. «). — Observa-
tions of Wolf's planet BP (23 February, 1895) made with
the great equatorial of Bordeaux Observatory, by MM.
O. Rayet and L. Picart, noted by M. G. Rayet. —
Volumes of salts in their aqueous solutions, by M. Lec"q de
Boisbaudran. — On M. fJarboux' method for the integration of
equations to the derived partials of the second order, by M. E.
Goursat. —On certain algebraical groups, by M. E. Cartan. —
On " fonctions entieres," by M. H. Desaint. The "fonctions
enticres" o( the type o, I or 2, of which the exponential
multiplier of the infinite product of primary factor" of M.
Weierstrass is of the form Ai<^>^'-+?r+y, where A is a constant,
-J and fl real and « positive, possess the property that, if their
■eros are real, the zeros of their derivatives are also zeal — On
the direct measurement of the mean spherical luminous intensity
of sources of light, by M. A. Blondel. A des'ription of the
instrument termed a lumen-tnltre and its use. — On the analysis
lif silicon, by M. Vig'iuroux. — Action of formaldehyde on
immoniacal salts, by MM. A. Brochet and R. Camhier. The
first action of ammonium chloride on formaMehyde may be
admitted to he the production of (CH, : NlI.HCDs. This re-
acts on healing as follows: 2(CH., : 5fH. HCI)3 + 3CH„0 4-
jHjO = 6(CH3.NH„,HCI) -t- 3CO2, giving a theoretical
yield. — On acid chlorides and aldehyde chlorides, by
M. Paul Kivals. The thermal data are given for mono-
chloracetic chloride and trichlora^retic chloride, and are
>hown t> vary in the same way as with the corresponding
icids. — Optical resolution of o-oxybufyric acid, by MM. Ph. A.
Guye and Ch. Jordan. The synthetical a. o^ySatyric acid is a
racemic form. The authors have succesfully separated the
U^vorotalory form from the dextrotatory form by means of their
brucine s.ilis. — On daturic add, by M. E. Gerard. The acid is
shown to have a real exi-tence, and forms definite metallic salts.
It does not consist of a mixture of stearic and palmitic ac'ds. —
(Glycogen in the blood in normal and in dialietic animals, by
.M. M. Kaufmann. Glycogenic inat'er is a constituent of
normal blood. The bloo I of animals rendered diabetic by
extirpa'ion of the pancreas contains much more glycogen than
that of healthy animals. — On the signification of the disen-
'^agement of carbonic acid by the isolated muscles of the body,
compared to that of the alisorption of oxygen, by M. J. Tissot.
The total quaniity of carbonic acid di•^engaged by a muscle
placed in tlic air ha- no relation with the phenomena of physio-
logical activi y, of which the isolated mu«cle is yet the seat.
Tlic absorption of oxygen is alone related to the manifestation
of physiological activity, the absorption being at the maximum
when the uuiscul-ir activity is greatest, and at the minimum
when it is dimini bed or on the point of disappearing. — On
the structure and afhniiies of Alicrosf'oron, by M. Paul Vuille-
min. The author includes MUrosporon vtilgare among the
Phycomycetcs, and not among the Saccharomycetes. It is not a
necessary parasite, is found on healthy skin, but is adapted
for parasiiis n, and is most abundantlv found in ihe epidermis
of new-forming spots of simole pyriasis. — On the embr>onic
develoument of tlie Dromiacean genus Dicranodromia, by
M. Eug Cr»u«tipr — On a new combination o( forms on quaitz
crystals, by M Fred. Wallcrant. — On an approximate esti-
mate of th frequency of earthquakes on the surface of the
globe, iiy M F de .Montessus de Ballore.

Berlin.
Physiological Society, February I. — Prof, du Bois
'veymond, President, in the chair. — After a discussion on Dr.

Cohnstein's communication on " intravenous infusion of sodium
chloride," Prof. G. Frilsch discussed the simjile principles on
which he had for many years obtained stereoscopic photographs
on an enlarged scale. He exhibited a series of these photo-
graphs, among which those of the inner ear excited particular
interest.

February 15. — Prof, du Bois Reymond, President, in the
I air ' rof. Zuntz gave an account of experiments, made in
conjunction with Staff- Surgeon Dr. Schumburg, on the effect of
load on the metabolism and body-functions of soldiers on the
march. Two students, feeding uniformly on a somewhat com-
plicated but accurately analysed diet, made on alternate days
marches up to 45 kilometres with a load increasing to 31 kilo-
grams. Taking first the nitrogenous metabolism, it was found
that the excretion of nitrogen through the urine and sweat was
but slightly increased by even the most severe exertion. The
slight lo^s of proteid thus noticed was made good in the sub-
sequent period of rest. .\t the end of each experiment the con-
sumption of oxygen was found to be greater than at the begin-
ning. When the marches were made on three consecutive days
with an increasing load, it was found that the consumption of
oxvgen was increased even at the beginning of the third day's
march, and was still further increased at its end. The body-
temperature rose to 38°-5 C, and in some cases to 40° C. The
heat production was three times as great as during rest, and the
regulation of temperature to compensate for this was almost
entirely brought about by the evaporation of sweat. The con-
centration of the blood was found to be but very slightly increased
bv exhau ting marches; the red blood-corpuscles were scarcely
more numerous than normally, whereas the white were mark-
edly increased in number. The movements of the heart at the
end of the experiments showed a lengthening of the systole
and distension of the right ventricle, whose dull area on per-
cussion, as also that of the liver, was extended during severe
exertion. The respiratory activity was at first, and with light
loads, improved, but later on difhculties of breathing made their
appearance. The psychic condition, as measured by the
reaction-time to simple stimuli, was not depressed by heavy
marches ; hut when fatigued the patients reacted more slowly
to complicated stimuli. Muscles not used in marching, were as
readily excitable at the end of the most severe march as during
complete rest. A high external temperature was found to exert
the same influence with a light load, as the heaviest load did at
more moderate temperatures, and some details of the experi- .
ments were found to depend on individual peculiarities.

Meteorological Society, February 5.— Prof. Hellmann,
President, in the chair. — Prof, von Bizold spokeon the uns'able
equilibrium of the atmosphere which precedes a thunderstorm.
The fact that in the interior most thunderstorms occur in the after-
moon and during the summer, whereas near the coast they are
most frequent at night and in the winter, shows that there must
be diflf-rent causes for the instability. As a matter of fact the
speaker showed that not only over-heating of the lower layers
of air, hut also excessive cooling of the upper layers, must Ie.ad
to unsta^ile equilibrium and a correspondingly powerful upward
current of air. A similarly unst.able state is brought about by
the sudden soliilification of strongly cooled water-drops, or the
condensation of airhighiy supersaturated with moisture. Thecon-
ditions for the realising of the above states are different in the
interior and at 'he coast or over the sea, and the mo le of forma-
tion of a thunderstorm is al-o corres londingly different. He
considered it very desirable that further observations of thunder-
storms at sea should be c .llected. — Mr. .\rchenhold exhibited
water-colour drawi-igs, made by Captain Henning in 1SS4, of
Ihe unusual twilights then occurring, he being at the time
ignorant of the abnormality as observed by others. One of the
most remarkable features in the drawings were the sharp and
straight lines of demarcation in the colours of the sky. The
speaker furiher exhibited a photograph of a halo he had
observed by moonlight.

Physical Society, February 8.— Prof. Schwalbe, President,
in the chdr. — Or. Neuhaus extiibited a series of colour photo-
graphs taken by Lippmmn's method wi h prolonged exposure.
Spectra show, if the exjiosure is sufficiently long, a greeni.sh
band in the infra-red as well as in the ultra violet, in addition
to the ordinary colours. The cohiured band was very markedly
displace i by both ovt- and under-exposure. Tne photographs
of objects with mi.xed colours, such as fruits, flower-, butter-
flies, &c., were also good ; but their production was extremely

NO. 1325, VOL. 51]

50-1

NA TURE

[March 21, 1895

diflicuU, and only one plate in twenly-Ave was, on an average,
sncccssfiil. It was found more easy to photograph naturally
mixed than artificially mixed colours. When describing his
methods, it was pointed out that some substance such as eosin
or cyanin must be added to the films to make them more
sensitire to red rays, and less sensitive to blue. When dealing
with the theory of colour photography, which was expounded
by Dr. Zenker as early as i86S, the speaker referred to a
number of difficulties which had not yet been solved. Thus,
io the first place, nobody has as yet demonstrated the existence
of the superimposed silver films in the gelatine, although they
should be visible under the microscopic powers now available.
In the next place, the presence in the gelatine film of granules
whose diameter is equal to several half-wave-lengths is not
reconcilable with the usual theory of colour photography ; so that,
on the whole, a comprehensive theory of the phenomena has
still to be established.— Mr. Archenhold gave some additional
details as lo the mechanical parts of the great telescope he had
described in the previous meeting of the Society.

February 22. —Prof, von Hezold, President, in the chair. —
Prof. Lummer spoke on the necessary corrections of dioptric
systems, and developed theoretically the possibility of the
law of points holding good for certain relations between focal
length and aperture. Prof. Kaoul Pictet spoke on the " criiical
point," and explained his own views, according to which sub-
stances must still be in the fluid state at the criiical point.
This follow- from the fact that the amount of heat which must
be put into the substance, as reckoned from absolute zero, is
less than the latent heat of the liquid, and the fact that solid
bodies do not separate out from solution at the critical tempera-
ture. They must be still in solution in the fluid, since they
separate out in the crystalline form by a further rise of tempera-
ture, and go into solution again as the temperature falls to
the critical point. This last fact was demonstrated by the
speaker on a solution of iodide of potassium.

Amsterdam.
Royal Academy of Sciences, January 26. — Prof, van ile
Sande Bakliuyzen in the chair. — Mr. Franchimont communi-
cated a paper on a new class of urea-derivatives, viz. the urea-
alcohols or ureols, one of which, ureo a.<thaDol, has been
prepared by the author and Mr. Van Breukeleveen. This body,
obtained from amino aeth.inol through Wohler's synthesis of
urea, forms colourless crystals, which fuse at 95°, .ind dissolve
readily in water, inuthyl-alcohol and ethyl-alcohol, but very
sparingly or not at all in most oganic solvents. It appeirs to
possess properties both of urea and of an alcohol. With nitric
acid it forms a compound, whi'"h is decomposed by so-calltd
real nitric acid at the ordinary temperature, with the formation
of carbonic acid and nitrous oxide. With benzoyl chloride it
yields a bcnroate, which fuses at 129", and is decomposed by
nitric acid in the manner described above. With acetic anhy-
dride and sodium .-icetate, a diacetyl derivative is obtained,
which fuses at 102°. — Mr. Hoogcwerff directed attention to an
apparatus, devised last summer by Mr. J. Boot. The object of
the apparatus is to easily and quickly gradu.ate retorts, pipettes,
and liurcttes, especially such as arc intended for techno-
chcmical researches. The firm of Kobb at Stiitzcrbach in
Thiiringen has been commissioned to make the apparatus. Mr.
Van dcr Waah showed that the conHition for the equilibrium
between coexistent phases, viz. the equality of the thcrmo
dynamic potential, may be deduced from ihc kinetic theory
byas>uming that the two phases iiitcchange an equal number of
particles, and may be regarded as a particular instance of the
more general law by which the kinirtic theory expresses the
density in different parts of a space, wherein the moving
molecules are subjected to the action of forces. — Prof.
Kamcrlingh Onncs communicated the resubs of investigations
in Ihc Leiden laboratory by : (i) Dr. L. H. .Sicrtscma on He
magnetic rotational dispersion of oxygen and nitrogen at a
ptessaie of 100 aim., giving the following relation between the

rotation w and the wave-length K: oxygen w = C. ^

(, -H ?:2Z^^), nitrogen «< = C. ''^'^^ (. -f "'ll^^'^)

and provinc »gain the superiority of Maskart's formula (see p.
470). (2) Dr. P. Zceman nn ihe Kerreflect in polar reflection on
iron and cobalt al normal iniirtcncc, lending to the conclu-inn
thai nfirc of the proposed lhcf>ries completely explain^ Sissingh's
pha«e -difference. (3) Dr. P. Zicman on ihc optic contlaote of

NO. 1325, VOL. 51]

magnetite, determined with regard to the relatiin betweei* '
Sissingh's phase in the Kerr phenomenon and the maximum of
magnetisation. (4) Mr. .\. Lebret on the variation of the Hall ,
effect in bismuth with temperature, it being found to be nearly '
linear between - 38° and 239°.

BOOKS, PAMPHLETS, and SERIALS RECEIVED

Books— The Pygmies : A. dc guatref.igM. t^an^hlIe<l by K. Suirr (Mac-
millan).— The German Iniversities. iheir Character and Historical De-
%eUpmcnt: Prof. F. Paulsen, translated by Prof. E. D. Perry (Macraillan).
— .\ Treatise on Bessel Functions and their Applications to Physics: Profs.
fJray and Mathews(Macmillan).— Meteorologv, Wcilher, and Methods of
ForecasUne, &c. : T. Russell (Macmillan)— Diary of a Journey through
Mongolia .-ind Tibet in 1891 and 1S91 : W. W. Kockhill (Washingion).—
Bourne's Handy Assurance Directory, 1S95 (SchoolioE).— An F.lcmentary
Texl-Book of Hydrostatics; W. Briggs and G. H. Bryan (Clivc).— The
Telegraphist's Guide (o the New Examinations in Technical Telegraphy:
J. Bell {Electricity OIBce).— The .Source and Mode of Solar Energy
throuKhout the Universe : Dr. 1. W. Heysingcr (Lippincott). — Handbook
of Jamaica, 18115 (St.anford).— Im Reiche des Llchtes: H. Gruson
(Braunschweig, Westermann).— Honest Money: A. T. Fonda (Macmillan).
— Collected Papers on some Controverted (Questions of Geology : Dr. J.
Prestwich (Macmillan).

Pamphlets NSW. Government Railways and Tramways— Annual

Report of ihe Railway Commissioners for the Year ending June 30. 189^;
Do., Supplement to the Railway ConTnissioners' .Annual Report.— Die
Reisen dcs /<ii<>« und der //t-r.'/r.r in das Antarktische Meer 1893-94 : Dr.
J. Petersen (Hamburg. Friederichsen).

Serials.— Science Progress, March (Scientific Press, Ltd.) —Medical
Magaiine. March (Strand).- Proceedings of the Physical Society of
London. Vol. xiii. Part 4 (Taylor and Francis).— Eoaineering Maga.^ine,
March (Tucker)— Memoirs and Proceedings of the Manchester Literary
and Philosophic.il Siciety. 4th series. Vol. 9, No. a (M.->nchesler)— Essex
Institute, Historical Collections. Vol. 30 (Salem, Mass.).— Journal of the
Franklin Institute, March (Philadelphia). — Intern.ationales Arehiv far
Ethnographic. Band vii. Heft 4 (Leiden, Brill).— Himmel und Erde, March
(Berlin).— Rendiconto delle Sessioni della R. .^ccad:mia delle Scicnze dell'
Istitutodi Bologna, 1892-93, 1S93-94 (Bologna).

CONTENTS

Modern Bacteriology. By Mrs. Percy Frankland . 481

Chemical Analysis. By J. W. Rodger 482

Analytical Geometry. By R. L 483

Our Book Shelf:—

Angot : " Les Aurores Polaires " 484

Kennedy : " A Few Chapters in Astronomy "... 484
Glazebrook : " Mechanics for Colleges and Schools : I

Statics " 484'i

Bell : " The Telegraphist's Guide " 484'j

Letters to the Editor: —

Corrections of Maximum and Ex-Meridian Altitudes.

(IVith Diagram.)— }. '^hiX.t 48S

Argon and the Periodic .System. ( Ifi/h Diagram.)

—Prof. J. Emerson Reynolds, F.R.S 4S6

Variation in Caliha /a/mins.—Piof. T. D. A.

Cockerell 487

Dr. M. Foster on the Teaching of Physiology in

Schools 487

Notes 488

Out Astronomical Column : —

Parti.il Kclipseof the Sun, March 26 49J

Distribution of Minor Planets 493

Solar Phenomena in 1893 493

The Royal Observatory, Edinburgh 493|

Physical Work of Hermann von Helmholtr. II. |

By Prof. A. W. Riicker, F.R.S 493(

Electrification of Air and other Gases. {///«.!■
IraUJ.) By Lord Kelvin, P.R.S., Magnus Mac-
lean, and Alexander Gait . . • 49!

University and Educational Intelligence 49'

Scientific Serials S"

Societies and Academies . . 5°*

Books, Pamphlets, and Serials Received . . . ■ y>'

NA JURE

505

\

THURSDAY, MARCH 28, iSgi.

ORB-WEAVING SPIDERS OF THE
UNITED STATES.

American Spiders and their Spinning Work ; a Natural
History of the Orb-weaving Spiders of the United States,
ivith Special Regard to their Industry and Habits. By
Henry C. McCook, D.D. Vol. iii., with descriptions
of orb-weaving species and plates (pp. 1-284, pi. i-
30). (Published by the Author, Academy of Natural
Sciences of Philadelphia, a.d. 1893.)

VOLS. i. and ii. of this work have been already
noticed in these columns. (See Nature, vol.
xlii., p. 244, 1890; Ibid, xliii., p. 74, 1S90.) The
volume before us completes the work, and bears
date 1S93 ; but it was only issued to the public at
the end of 1894. To the general reader this is a
matter of little consequence, but to the specialist it is
often important, for it frequently happens, as in this
instance, that new genera and species are characterised
and described ; it then often becomes necessary to decide,
on the questions of priority that may rise, as exactly as
possible when such descriptions were made, and the date
inscribed on the work, it is manifest, cannot be implicitly
relied upon.

In the preface to the present volume, it is stated that
the work has engaged the author's thoughts for more
than twenty y ars, and to this the amount of research
and observation testified to in three large volumes amply
bears witness. The first six chapters of vol. iii. (pp. i-
131), being part i., are a kind of supplement to vols. i. and
ii., and are "on various natural habits and physiological
problems'' of spiders. Part ii. (pp. 132-277) carries out
the prospectus of the work at first issued, viz. descrip-
tions of the American " orb-weavers," illustrated by
thirty coloured plates of great beauty and accuracy,
especially in regard to the anatomical details; two, how-
ever, of these plates are of spiders of various groups and
species alluded to in the foregoing part of the work,
though without special description. The author speaks
of this portion of his task (part ii.) as in many respects
its most difficult part ; but this may be taken as tolerably
certain, that though vols. i. and ii. and the first half of
vol. iii. will always be the most popular part, the latter
portion of vol. iii. will prove of most value to the scientific
world. The observation and detailing of habits, man-
ners, and general economy, whether of spiders or any
other group in the natural world, afford unlimited scope
for imagination, sentiment, as well as popular and
picturesque description, all of which the true scientific
worker has resolutely and wholly to shun, or, at any
rate, to repress with a strong hand. It seems almost a
pity that these two distinct portions of Dr. McCook's
work had not been issued separately, as the total cost
of the whole — 50 dollars — is a heavy sum to pay for
the 136 pages and thirty plates, which will alone be
indispensable to the systematic working araneologist.
Nor will it be possible (we are told in this vol.) to obtain
vol. iii. apart from the other two.

.All that was said in the notices, above alluded to, of
Aols. i. and ii. can be again here repeated in praise of the
NO. 1.326, VOL. 51]

execution of the work in this third volume. Chap. i. is
"on toilet, drinking, and social habits"; chap. ii. on
"memory, mimicry, and parasitism"; chap, iii, "bio-
logical,miscellany" ; chap. iv. "on weather prognostica-
tions, sundry superstitions, and the commercial value of
spiders' silk"; chap, v., "on moulting habits of spiders " ;
chap, vi., " regeneration of lost organs, and anatomical
nomenclature." On all these subjects there are many
most interesting and useful observations.

In chapter i., p. i, speaking of spiders' habits of
cleansing themselves of objectionable matters by their
having a spiny armature of the legs and mandibles [fakes),
so evidently well adapted for the purpose, it is asked,
" Did the habit of cleanliness arise from the possession
of these implements, or were the implements developed
out of the vital necessity for a cleanly person.^" In the
first place, it suggests itself as hardly tenable to assume,
1) priori, such a vital necessity in respect to spiders, any
more than with regard to some Acarids, or the larva; of
certain insects, whose habit it seems to be not only
to need no cleansing, but to encourage the accumulation
upon their bodies of various kinds of adventitious and,
at times, of even excrementitious matter; but not to
dwell on this view of it, the case of the spiders
might perhaps be simply presented in this way. The
accumulation of dust, or soil, or what not about them,
arises mainly from their having clothing and spinous
armature, in which those substances become entangled
and retained, while at the same time those very causes of
the inconvenience become the means of obviating it ;
for we may take it that the first efforts of a sentient
being are to rid itself of whatever may adhere to it, to
its hindrance or annoyance ; in this process, whatever
existing portion of structure came handiest would
necessarily be the first used, whether, as in the case of
cows and other horned cattle, the lashing of its sides by
a heavily-tipped tail, or the muscular movements of the
ears, or the action of the hinder hoofs ; but it would
scarcely be argued, either, that the ears, tails
or hoofs of cows were developed just for the purpose
of ridding them of insect or other inconveniences,
or that the habit of so using them arose out of the
animals' possession of ears, tails, and hoofs. Nor can
we, it is conceived, argue either that spiders'
habits of using hairs and spines in cleansing themselves
arose from the possession of such implements, nor that
these implements were developed from those habits. \\\
that we can say with any certainty, seems to be that
while hairs and spines, &c., were developed by various
means and for various ends, the more perfect adaptation
of soine of them for special functions would no
doubt be eflected by natural selection ; such, for instance,
as the development of the calamistrum on the metatarsi ot
the fourth pair of legs in numerous widely separated
genera, and even families of spiders, for the utilisation
of the silk-matter of the supernumerary spinners, which
last are always found correlated with the calamistrum.
Under the heading of " Burrowing Spiders," pp. 31-35.
we have a very interesting and important account of
trap-door nests made by Lycosid spiders ; those hitherto
known as " trap-door spiders " having been exclu-
sively of the family Theraphosida-. .-^ remarkable
account of a spider apparently voluntarily changing its

;o6

NATURE

[March 28, 1895

colour, is given at p. 51. This account, it seems, is taken
from Natl-re, April 13, 1S93, p. 55S ; but it appears to
need corroboration.

Among other points in respect to spiders' spinning
work, the use and commerical value of the pro-
duct is naturally referred to (pp. 83-S9), and the
various experiments (already published from 1709 to the
present time) made to ascertain their use and value are
noted ; but the subject does not seem to have attracted
much attention since Prof. Wilder's experiments in
1S65-1S69. Some subsequent researches made by a
Mr. Stillbers, an Englishman (quoted in a paper by M.
Guatier), appear to need more circumstantial reference
and explanation. It may, however, be mentioned here,
that in 1SS4 a small mass of spider's silk was received,
through Prof. Thiselton-Dyer, by the present writer,
from .•Vlmora, Saharunpur, India. This was mixed up
with the debris of dead insects and spiders, as well as with
portions of the plants among which the silken webs were
spun. Some of this mass was examined by .Mr. Thoma s
Wardle, who reported upon it in the Journal of
the Society of .Arts, May 1885 (pp. 679-680). In an
exhaustive paper in that journal, on " Researche s
on Silk Fibre," Mr. Wardle says, in the course of his
report :—

" I believe, if it can be obtained in quantity, it mig ht
be packed in bales and sent to England, where it wou Id
readily find a market for being carded and span inti s ilk
threads for sewing or weaving purposes. It is dirtic ult
to estimate its market value. I dare say it would, at any
rate, realise one shilling to two shilUngs per lb. It is
rather dirty, and this would to some extent detract from
its value as compared with silk waste."

The spider to which this silken miss was referable is
Sephilengys {Epeira) Mahibarensis, Walck , a species
of very wide tropical distribution, and apparently in
great abundance where it occurs. There seems to be
no reason why almost any amount of this silk should
not be obtainable from the low plants and s;rub on which
the spiders spin their snares, and, with a little care in
gathering, much less intermixed with dirt and other ad-
ventitious matter than the sample above alluded to. In
fact, we may easily conceive that it would be possi ble,
with a little trouble, to form a kind of spider-farm for th e
purpose of producing this silk in the greatest possib le
perfection and abundance. From Mr. Wardle 's analysis
and treatment of this silk, it may be seen that it possesse s
some very valuable and curious characters.

The chapter on " Moulting Habits " is full of exceed-
ingly interesting details, both from published works and
the author's own observations. .Moulting is a critical
operation in spider-life, and is usually attended with a
great demand on the vital powers of the spider ; and
though spiders probably seldom succumb when in a state
of nature, moulting, when in confinement, frequent ly
proves fatal, especially when the spider is advanc ed in
age. A large Theraphosid, for eighteen months kept in
confinement in the gardens of the Zoological Society of
London some few years ago, died at length in its last
moulting process. After the last moult, which comple tes
the structural development of the spider, it seems that
no further ccdysis takes place, whatever age the spider
may attain. The number of moults appears to vary, not
only with the species, but with individuals of the same
NU. 1326, VOL. 51!

species ; food, temperature, and other conditions no-
doubt affecting it. Chapter vi., on " Regeneration of
Lost Organs," is based chiefly on the researches of
Voldemar Wagner (" La regeneration des organes
perdus chez les Araignees," Bull. Soc. Imp. Moscow^
18S7, No. 4) and the observations of H. Heineken {Zool.
Journ. iv. 1S28-29). Papers on the subject by the late
Mr. Blackwall are also noted.

Part ii. consists of " Descriptions of Genera and
Species." In his introductory remarks to this part.
Dr. McCook defines the extent of the group comprised
in his " Orb-weaving Spiders." This is coextensive with
the " Orbitelarix" of Dr. Thorell, and includes Uloborus,
which is far removed structur.illy from the Epciridcs, as
well as Pathygnatha., which, so far as known, spins no
snare at all. The dit'liculty of drawing any decidedly
marked line between the Retitelaria, and Orhitelaricz is
no doubt great. Witness the results arrived at by
M. Eugene Simon in his work now in progress —
"Histoire des .\raignees," second edition, 1893-4— in
which these two enormous groups are fused, and again
subdivided: the materials being recast in a way which
upsets all the previously conceived ideas of araneologists.
However, until these new views are better understood
and generally adopted, the old division into geometric
web weavers and those whose snares are not geometric,
but net-like, with exceptions such as the Uloborida: and
Pachygnatlux, are sufficient for popular as well as faunistic
purposes.

At pp. 8 and 133, reference is made to drawings of
American spiders made by John Abbott early in the
present century, and the descriptions of which are
contained in Baron Walckenaer's Ins. Apt., a.d. 1837.
It appears from Dr. McCook 's remarks that he was
under the impression that some drawings which he
saw in the British Museum in 1887 were the original
drawings of John Abbott's spiders. This, however,
is not so. The British Museum set of drawings are
either a copy of those of Abbott, or, may be, a dupli-
cate set done by .Vbbott himself. The originals (or,
at any rate, those from which W.ilckenac r drew up his
descriptions of the spiders) are in the possession of the
authorities at the Jardin des Plantes, Paris. Many
years ago it was proposed to the present writer by
the late Dr. John Gray, of the British Museum, to
prepare and publish descriptions of the spiders from the
British Museum copy, along with plates engraved some
years previously from that copy, under Dr. Gray's
orders. Such descriptions, however, it is ciuite obvious,
could not possibly be done satisfactorily from the draw-
ings alone— witness Baron Walckenaer's efforts— though
no doubt numbers of the spiders delineated can, with
more or less certainty, be specifically determined from
them. The result of an inquiry made at that time,
was that the French nation h:is .Abbott's original drawings,
which were presented, directly or indirectly, to Baron
Walckenaer by Abbott himself; but what the British
Museum set was, or how it was actiuired, seemed to be
very doubtful.'

In a general notice like the present, part. ii. of the vol.

1 Dr. McCook cvidenlly wjs not aw.irc ih.il the present writer, in a
review ol N. M. Hentz's '• North American Spiders" m 1876 (I^ATUHB.
vol. xiii.p. aiv). meniiom theie fact-, a ri cjasi Jcralioni respecting Jolm
Abbott'i drawinKi.

March 28, 1895]

NA TURE

507

under consideration needs but little remark. The de-
scriptions are full and accurate, and the figures are nearly
all engraved from drawings beautifully executed by Miss
Elizabeth F. Bonsall, and leave but little to be desired.
Three, however, of the plates— Nos. 2, 10, and 15— are
from the author's own drawings, and are fully equal, if
not superior, to the rest. 123 species of spiders of the
orb-weaving group are described, and, of these, twenty-
four are considered to be new to science. Four new
genera are also characterised. In every way, part ii. will
be of great use and importance to systematic araneo-
logists. A portrait of Nicolas Marcellus Hentz (justly
called the father of American araneology) forms a most
appropriate frontispiece. O. P. Ca.mbridGE.

THE SEA AND ITS COASTS.
Sea and Land, Features of Coasts and Oceans, with
special reference to the Life of Man. By N. S. Shaler,
Professor of Geology in Harvard University. Illus-
trated. (London : Smith, Elder, and Co., ■ 1895 )
IN more than one sense this book is a thin",er one
than " Aspects of the Earth." Of the seven essays
which it contains — in the main republications — the first
four deal with familiar subjects — the work of the sea, its
beaches, its depths, and icebergs ; the last three treat of
harbours, and introduce some ques tions which are less
hackneyed and more interesting. Prof. Shaler writes
pleasantly, and his sentences flow easily, but it is some-
times possible to read throu gh several paragraphs without
much progress in knowledge, or to find a rather large
number of well-turned phrases expended in stating what
amounts to a truism. But as the preface informs us
that the object of the book is " to introduce unpro-
fessional students of nature to certain interesting
phenomena of the sea- shore and of the depths of the
ocean," it is very possible that babes in science will find
well-sweetened pap more digestible than strong meat.
We must, however, protest against the liberties which
Prof. Shaler takes occasionally with our mother-tongue.
He is too fond of " telephonese" or "telegraphese," as it
might be called This tongue may be good American,
but it is not good English. We do not mean to assert
that no improvements could be made in the latter, or to
pose as prudes of etymological purity, but we object to
the coinage of new words, or, rather, the misuse of old
words, where grammatical expressions already exist,
longer only by a few more letters or, at most, syllables.
Brevity may be the soul of wit, but it is not always an
adornment in speech. Is there any real gain (to take a
few examples) in such an adjective as " pivotal," such
participles as " fiorded," " forested," " peninsulated,"
"well-harboured" (i.e. with many harbours), and such a
verb as to "raft off" in the sense of transport or carry
off like a raft.

Prof. Shaler is a picturesque writer, and his descrip-
tions usually are clear and vivid ; but dangers lurk in
the attempt to be graphic when a locality is known only
at second-hand. Of this the book before us affords an
amusing instance. Speaking of the advance of dunes,
he quotes the well-known case of Eccles (Norfolk),
saying : "Thus in Britain one of these dunes in the last
century invaded the village of Eccles, and buried the
NO. 1326, VOL. 51]

dw ellirgs ar.d the parish church, so that even the top of

the spire was hidden. After a number of years the

su ir.mit of the church began to reappear on the leeward

[.' windward] side of the hill, and in time the remote

descendants of the dispossessed people may be restored

to their heritage." But the dwellings had practicallv

disappeared before the dunes rolled over them: the

chuich had been a ruin for at least two centuries ; of its

body only the foundations remained ; there was no spire,

and apparently never had been one ; and the octagonal

lantern of the tower was never wholly buried, unless

the well-known engraving in " Lyell's Principles of

Geology" represents an exceptional condition of the

s andhills. So if the descendants of the original villagers

do return to their ancestral domiciles, they will find

t htmselves " Lords of the sands, an heritage of waves."

I ndeed, since Prof. Shaler wrote, even the old tower has

tumbled down, destroyed by the waves during a gale

last January.

We venture also to think that Prof. Shaler takes rather
too much for granted in assuming, without a hint that
this has been disputed, that great rock basins have been
excavated by glaciers. Moreover, he is hardly correct
in saying that fjords are restricted to ice-worn regions,
for Cornwall can show more than one very respectable
imitation of such an inlet, and on the Dalmatian coast
they are not rare ; yet we can hardly suppose that even
in the coldest part of the Great Ice Age, precipitate
glaciers descended from the Montenegrin Highlands to
scoop out the Bof.che di Cattaro. But perhaps an inlet
of the sea only becomes a fjord when it shallows towards
its mouth ; if so, that should have been clearly stated.
Doubtless these basin-like fjords are difficult to explain ;
but as Prof. Shaler admits the existence of submerged
moraines, no excavation need be required. At any rate
it would be well, as a preliminary step, to prove that
glaciers are agents of excavation to any important
extent, for this has been denied by many geologists, who
vainly ask to be shown any proofs of such effects in the
s ubacrial part of their course.

But we must not dwell too much on blemishes, which
after all are light. Even the four earlier essays, already
mentioned, exhibit a certain freshness, for Prof. Shaler,
as an American, selects the majority of his examples
fr om the other side of the Atlantic, instead of using those
which have become the stock-in-trade of every European
geologist. By this ijieans more than one point is
br ought out more clearly than is usual in English
books, because illustrations aie difficult to obtain
fr om our own islands, or any readily accessible part of
the neighbouring continent. For instance, his remarks
on the action of vegetation in a shallow estuary or bay,
and particularly on the growth of "mangrove s^vamps"
are valuable. He describes how the large tapering
cyl indrical seed of the mangrove, floats in a vertical
position, settles down and becomes entangled on the
bottom by means of the numerous booklets which arm
its lower extremity, then sends a shoot up above the sur-
face of the water, from which come wide-spreading, low-
growing branches. From these long runner-like processes
are thrown off, which at last curve sharply downwards
through the water till they strike root at the bottom, and
then support new crowns, each having its own trunks

5o8

NA TURE

[March 28, 1895

and branches " Thus a single tree may rapidly march
away from the original planting-point until its outer verge
may be an indefinite distance from its place of origin."
This method of growth enables the grove to resist even
fairly strong waves, and facilitates the accumulation of
organic debris and inorganic sediment.

Again, there are some striking remarks on the accumu-
lation of molluscs, especially bivalves. Prof. A. Agassiz
has already called attention to this process on the great
Florida plateau, and Prof. Shaler particularly mentions
the special importance of the oyster as a rock builder
along the whole coast from New York southwards.

" In its maximum development " he says, '' the larger
part of the shallow bottom inside the ocean beach is
occupied by beds of these shells. So crowded are these
forms, that they push their growth above the level of low-
tide mark, and in the region where the mangroves
abound they cluster on the roots of the trees to such
numbers as often to hide them from view. . . . Between
Charleston, South Carolina, and liiscayne Bay, Florida,
there is an aggregate area of nearly a thousand square
miles which, when the shore assumed its present elevation,
was occupied by tolerably deep water that has now
become filled to near the level of high water, by sediments
composed in large part of oyster-shells."

In fine, these three essays contain not a few
interesting and suggestive passages. The illustrations
often are very good.

THE CHEMISTRY OF COD- LIVER OIL.
Cod-liver Oil and Chemistry. By F. Peckel M oiler,
Ph.D. (London: Peter Miiller, 43 Snow Hill, E.C.,
and at Christiania, Norway, 1895.)

THIS book is divided into two parts — the title of
part i. is " Cod-liver Oil " ; the title of part ii.
is "The Law of Atomic Linking, diagrammatically
illustrated," and the heading of the first chapter of the
second part is " Chemistry." There is a separate
preface to each part, and, though bound together in one
volume, each forms an independent treatise, and is
separately paged. One hundred and eleven pages are
devoted to " codliver oil," and rather more than five
hundred to " chemistry."

In the preface to the first part the author gives two
reasons for the publication of ihe work : (r) to deal with
.all m itters connected with cod-liver oil, and especially
with those likely to be of interest to members of the
medical profession ; and (2) to give the results of the
investigations lately undertaken by Mr. Heyerdahl, which
" throw the first and only true light on that mystery,
the real nature of the oil."

The first and second chapters give an interesting
account of Norway, which is styled " the land of the mid-
night sun and codliver oil"; its people, past and
present ; its social customs ; the Gothenburg system in
every town ; its land question ; its fisheries, fishermen,
and fishing boats, their tackle and bait ; its tourist
visitors, and its " oldest established visitor," the cod-fish.

The next chapter is on " cod-liver oil,' and the
reader is instructed, as pleasantly as in the preceding
chapters, in the ancient and modern methods of pre-
paring the oil for use. The older method, it appears,
was in use until so late as the year 1853, when a
NO. 1326, VOL 51]

great improvement was effected by the introduction of
the steam process of extraction, by which means the
pure oil only is obtained from the livers, instead of oil
mixed with a great number of decomposition product?.
This steam process was a great advance. The resulting
oil had lost much of its objectionable taste and smell,
but it still retained one very bad characteristic — it was
still very apt to give rise to nauseous eructations.
Unwelcome flavours continued to assert themselves after
a dose of such oil, not once only but again and again,
till, as the author says, the unhappy recipient was
tempted to say, " life is not worth living if it is to be
only at the cost of taking cod-liver oil." Hence the
host of attempts that have been from time to time made
to treat the oil so as to abolish these disagreeable
properties. These are dealt with in the chapter called
" Pharmaceutical Annotations," and some forty different
ways of disguising or improving the oil are described
in detail — the ingredients for mixing with the nauseous
article including such diverse things as beer, iron-
water, peppermint oil, coffee, eucalyptus oil, wood-tar,
ammonia, ketchup, celery-seed infusion, vinegar,
iodoform, saccharin, acetic ether, &c. ; and, besides
all these, every conceivable form of emulsion seems
to have been tried. It will be welcome news to
many that, in Dr. Moller's opinion, all these elaborate
preparations are now quite uncalled for, and that
Heyerdahl's investigations have at length led to the
possibility of an oil being produced more curative
than the old oil, and quite free from nauseating powers.
These researches are fully described in a separate chapter,
and are considered to have revealed the presence in
the oil of two hitherto unknown glycerides, which have
been named, respectively, thcrapin and jccolein. They
are both exceedingly unstable compounds, and easily
become oxidised, and these oxidation products are
believed to be the real cause of the too well-known
unpleasant after-effects of the drug. As a result of these
discoveries an apparatus has now been devised by which
cod-liver oil can be produced on a large scale without
even the slightest oxidation taking place. Air is
excluded from the beginning to the end of the operation,
the process being conducted in a current of carbonic
acid from the moment the livers enter the apparatus
until the oil obtained from them is safe within the
bottles.

The chapter giving a synopsis of the chief researches
on the oil since 1822 is very complete, and will no doubt
prove of great interest to medical men and pharmacists.

The conclusion arrived at as to the therapeutic agent
in cod-liver oil is that " it is the oil itself," and that its
remarkable power as a nutritive food is the cause of its
medicmal elticacy, and not any special active principle
contained in it. This opinion is in agreement with tl1.1l
of the late Prof. J. Hughes Bennett, of Kdinburgh, who
published, in 1841, a pamphlet on cod-liver oil, which had
much to do with the general introduction of the oil as a
medicine into this country. It is one of the omissions
in the present volume that no reference is made to the
work of Dr. Bennett in this direction.

The object of the second part of this work, as set
forth in the pref.ice, is mainly to bring the facts of
organic chemistry, freed from unnecessary difficulties,

March 28, 1895J

NA TURE

509

within the grasp of busy medical practitioners. With
this object graphic formulae are profusely employed, so
that "a glance will lay bare to the eye of the novice the
whole details of the constitution of the most complicated
compounds," and the practical preparation of the com-
pounds has been generally omitted " because the much
tried patience of medical men need not be burdened
with things chiefly of interest to the chemist." With
these exceptions a large proportion of organic chemistry
is very fully treated, and a careful reading of the work
in leisure motnents would doubtless give any one, who
had some previous knowledge of the science and some
liking for it, a fair grasp of somewhat more than the
outlines of this vast and ever-increasing field. Especially
interesting, though demanding more than cursory
reading, is the concluding chapter on atoms, linkage,
and stereo-chemistry. In our earlier days chemists did
not so much concern themselves with these things. The
determination of mere composition and formuhc furnished
enough occupation. But with advance of knowledge
it has been found necessary to study what has been
called the "atomic architecture of molecules." In the
concluding pages this subject is very ably anu lucidly
discussed. A new hypothesis is suggested, to which the
name of the " screw theory '' is given, which, it is pointed
out, may satisfactorily explain those cases of optical
activity which are met with in certain bodies, e.g. some
terpenes and glycerides, where there is no asymmetrical
carbon-atom, and which are consequently not clearly
met by van't HotT's ingenious theory.

The volume is one in the production of which great
labour and care must have been expended, and both
parts are worthy of commendation. Possibly, however,
it would have been advantageous to both, if they had
been published separately. J as. Cameron.

OUR BOOK SHELF.

Aslronomische Chronologic. By Walter F. Wislicenus. I
(Leipzig: B. G. Teubner, 1895.)

Historians, archaeologists, and astronomers will hail
with delight this work, as it fills a gap which for some
time past has been very apparent. At the present day,
to take one case only, archaologists are busy in Egypt
deciphering and unravelling the legion of myths which
are there recorded in the many forms and ways peculiar
to that country. Many of these myths are, as has been
recently more clearly pointed out, purely astronomical
in their nature ; and this is perfectly natural when one
considers that the Egyptians, or, at any rate, the priests,
for these were the chief writers, were astronomers.
Archxologists in fathoming these depths are perfectly at
home when arch.Lology is in question, but as soon as the
astronomical boundary is reached, and astronomy pure
has to be attacked, then perfectly dillerent problems are
met with. In like manner, the astronomer himself,
going from the astronomical to the archaeological side,
is also nonplussed, unless he wishes to enter somewhat
generally into the study of Egyptology. In the book
which we have before us, Dr. Wislicenus gives the
historians and archasologists a helping hand, and presents
them with the necessary means and ways of solving
some of the problems which are generally encountered.

Without entering too minutely into' the contents of
these 150 odd pages, a general survey of the text will
best give the reader an idea of their character.

NO. 1326, VOL. 5 l]

The two parts, into which the book is divided, deal
respectively with the fundamenta of astronomy, and the
different methods of computation.

The former part is concise and brief, and the author
in forty-four pages presents the reader with a general
summary of the different systems of coordinates used,
the different kinds of years, the course of the moon,
eclipses, daily and yearly rising and setting of the
heavenly bodies.

The methods of computation in the second part are so
arranged that they follow, in the same order,the text in the
first. At the commencement of this part Dr. Wislicenus
brings together a list of the numerous tables which are
used for the solution of chronological problems. These
are here given with their full titles, and are explained
further on. The remainder of the book is devoted to
the solutions themselves, and these are arranged as
follows : First, the known and the unknown quantities
are separated, then the tables to be used in the problem
in question are explained ; following these, typical
examples are taken and worked out by the use of the
different tables.

A very full index makes reference easy, and completes
what will prove a very useful book. W. J. S. L.

Die dltesien Karten der Isogoncn, Isoclinen, Isodynxm^n

By Prof. Dr. G. Hellmann. (Berlin : \. Asher and

Co., 1895.)
This is the fourth of the elegant series of reprints de-
voted to classical contributions to meteorology and
terrestrial magnetism. It contains seven maps, all
excellently reproduced, and representing old standard
charts of isogonic, isociinic, and isodynamic lines. The
maps portrayed are Halley's Declination Chart of the
World, published in 1701 ; Whiston's two maps (l7-l),_
showing lines of equal magnetic Dip in the South of
England ; J. C. Wilckes Isociinic Chart of the World
in 1768 ; a chart by Humboldt, published in 1804, show-
ing Isodynamic lines over part of South .A^merica ; and
Hansteen's Isodynamic Charts (1825-26) of North-West
Europe and of the world.

Halley's description of his " New and Correct Sea-
Chart of the Whole World, fliewing the Variations of
the Compass,' is reprinted, and brief descriptions are
given of the other maps.

Whiston, it may be remembered, suggested that longi-
tude might be determined from magnetic inclination,
this element being preferred to declination for reasons
which he stated as follows : '■ When, therefore, I con-
sidered that the Lines of equal Dip could hardly be more
irregular than those of the Variation ; I well knew that
;\Iutation was a great deal slower : and that these might
probably be useful overall the World ; I conceived great
hopes that this way of Application of the Power before
us might very probably discover the Longitude."

Prof. Hellmann contributes a number of biblio-
graphical notes, and these, with the maps, make the
reprint a compact and useful_work of reference.

An Elementary Text-book of Hydrostatics. By W.

Briggs, M.A., and G. H. Bryan, .M.A. Pp. 208.

(London: W. B. Clive, 1895.)
The portions of hydrostatics and pneumatics usually
taught to beginners, and required for the matriculation
examination of the London University, are concisely and
clearly treated in this book. Though evidently con-
structed for examinational purposes, the book contains
a number of good points. The mathematical formula;
are deduced from first principles instead of being stated
dogmatically ; so the student is led to rely more upon
his real knowledge, and less upon mere memory. This
and other commendable features distinguish the volume
from ordinary text-books of hydrostatics, while the
numerous problems, covering a wide field, furnish clear
evidence ot originality.

510

NA TURE

[March aS, 1895

LETTERS TO THE EDITOR.

\_7kt Editor does not hold himself responsible for opinions ex-
pressed ty his correspondents. Neither can he undertake
to return, or to correspond with the writers oj, rejected
manuscripts intended for this or any other part of NaturK.
No notice is taken of anonymous communications.}

The Statistical Investigation of Evolution.

Mr. Thiselton-Dver states ihat Prof. Weldon his shown
that "selective destruction " takes place in early life amangst
individuals which deviate from the "mean specific form." lie
further says thai the actual statistical demonstration of the fact
that "minimum destruction is in position coincident with the
mean of the whole system," deserves to rank amongst the most
remarkable achievements in connection with the theory of
evolution. But, to judge from the paper by Prof. Weldon,
printed in Nature of March 7, he does not claim to have made
this remarkable achievement. He says that, according to the
results of the statistical investigation, in two dimensions of the
shore crab, the frequency of deviations increased during an
early period of growth, and that in one case the increase was
followed by a decrease ; in the other case it was not. Prof.
Weldon stales that if a certain law of growth can be shown
to be true by experimental tests, then the result implies
a selective destruction in the one case and not in the other. So
that all we have is the possibility in the future of a statistical
demonstration of selective destruction in the case of one par-
ticular dimensional character, and the rigid proof in the present
that in the case of the other dimensional character selective de-
struction does not take place. Surely every man of science
must admit that Prof. Weldon's results, on his own showing,
have done more against selective destruction than for it.

Prof. Weldon says that if we know that a given deviation
from the mean is associated with a greater or less percentage of
death-rate, wc do not require to know how tiie increase or de-
crease of death-rate is brought about, and all ideas of functional
adaptation become unnecessary. This may be his own state of
mind on the subject, but I venture to state that it is not Dar-
winism, and that he cannot shut out others fro:n the most
interesting and most important fields of biology in this way.
Darwinism states that selective destruction is caused by the
struggle for existence, and that a selected character confers an
advantage in the competition to get food and beget offspring.
If a certain deviation is shown to be associated with an increased
or decreased chance of life, we want to know how it acts, and
no statistical Gallio can prevent us trying to find out.

It does not require much search to find deviations which are
associated with an increased death-rate. In the human subject
cyanosis, due to the retention of the fecial communication be-
tween the two sides of the heart, is a well-known abnormality
or deviation in the infant ; but I believe few, if any, children
born in that condition reach the age of 20. Here we have no
difhculty in understanding the reason : the deviation necessarily
leads to death. But now, in comparison, lake the case of a
child born blind, or deaf and dumb. Here there is no intrinsic
reason why life should be shortened ; but in a severe com-
petition, it the individual dejiended entirely on his own exer-
tions, he might be, probably would be, starved or trampled to
death before he had lived very long. I think it is of some
interest and importance to know of any given character or
deviation, whether it is intrinsically harmful or beneficial,
extrinsically so {i.e. in the struggle for existence and repro-
duction), or quite indifferent.

Prof. Weldon is silent, to some extent, about the cases which
tell against the idea of -elective destruction. He found that
deviations in Aurelia were as numerous in the adult as in the
Ephyra:. He told me in conversation, and did not say it was
in confidence, that he abandoned some experiments on the selec-
tion of Daphnia, because he found that the mere fact of keei>ing
a large number in the same water caused a progressive dis-
appearance of a certain conspicuous spine. His invcs.igations
also entirely ignore the diagnostic value of the characters he
deals with. It seems to me that a more valuable result woulil
be gained if a parallel investigation were made of two charac-
ters— one obviously di-ignostic, the other obviously adaptive.
Such char.-ictcrs could be found in a swimming crab.

But above all, what wc want is a comparative investigation
of the results of (election without change of conditions, and of
change of conditions without selection. I began, not long ago,

NO. 1326, VOL. 51]

to try to inaugurate a society for carrying on a thorough inves-
tigation of this kind, but have not at present received enough
support to carry out the scheme. The method of the inves-
tigation is fairly obvious and not difficult, but the difficulty is to
get the money and the time to carry it out. I ciili'er from Prof.
Weldon in thinking that the questions raised by the Darwinian
hypothesis are not purely statistical, but experimental, and I
agree with Mr. Thiselton-Dyer— that to talk of experimentally
checking the hypothesis by the statistical method is a con-
tradiction in teims. J. T. Cunningham.
Cleethorpes, March 15.

A True Spectrum Top and a Complementary One.

To make a true specirum top — whicli is not copyright, so far
as I know — take a disc of white paper, and one of black, of
equal size. Spin the white one on a disc of cardboard mounted
on a nail, an 1 while it Is spinning draw a small brusli well
charged with lamp-black water-colour paint, steadily and not too
slowly from centre to circumference of the disc, thus describing
a spiral line. Make a radial cut in each of the discs, and after
interlocking them as in the well-known colour discs, place them
on the top. We thus obtain a top in which the lines are spiral,
and the relative sizes of black and of white areas are easily
regula'cd by turning one disc to right or left, while the other
is held still. If the lines be not too thin or too thick, and not
loo near togeth r, and if the relative areas of black and white
be adjusted suitably to the light, the top exhibits, when spun,
broad bands of colour, each band containing all the colours of
the spectrum in their natur.1l order. The spaces between the
lines should be not less than five times as broad as the lines
themselves. The brightest effects are produced in my own case,
by lamplight, with the areas of light and dark almost equal ; by
daylight, with the dark area about three times as great as the
light. Other proportions, however, seem to give better results
with other people.

A " complementary lop," yielding colours complementary to
those of the spectrum {i.e. the colours of mother-of-pearl) in a
continuous band ranging from lemon-yellow, through puce to
electric-blue green, is made in the same way, except that the
.spiral line is to be drawn in wliite on the black disc.

In both cases the colours are somewhat dilute, but the proper
regulation of the relative areas of black and white reduces this
defect very considerably, and I have obtained bands on my
spectrum top brighter and purer than any which I could get by
painting a specirum with colours on paper.

I communicate this description before my experiments are
complete, in order to prevent anyone who may make the same
discovery, from obtaining a copyright for the design of either
these tops or of earlier ones which I made, in which one half
the disc was black and the other white, with a white spiral on
the black, or a black spiral on the white, or with both at dilTerent
dist.ances from the centre on the same top. .Vnyone who wishes
to do so may make as many tops or lantern-discs as he chooses
from the above description, jirovided he does not attempt to
hinder anybody else from making or selling similar ones.

C. Hekuert Hurst.

Owens College, Manchester, March 24.

A Foucault Pendulum at Dublin.

It may perhaps interest some of your readers to loam that
Koucault's pendulum experiment has recently been performed
in Trinity College, Dublin, with complete success.

Immediately under one of the glass domes, by means of which
the hall of the New Building is lit, a cast-iron bar was securely
bolted, which terminatis in a cylindrlcallyshaped piece of metal
the axis of which is vertical. Into this cylinder a steel plug
was inserted, which was drilled to receive the upper end of
the wire supporting the Imb, which was fitted with a screw,
liy placing the upper end of the wire in this position, I'rnf.
FilzGcraldand I secured a kngth of 45 feet for our pendulum ;
but, under the circumstances, we were unable to use the same
weight as that adopted by Sir R. Hall when making the
experiment, viz. 300 lbs., and were obliged to content ourselves
with a liub weighing 16 lbs., which, however, answered
admirably.

The experiment is made in the following manner :— About
two feet behind llic position of equilibrium of the bob, wc place
the electric lamp, and at a suitable distance in front a lens, so

March 28, 1895 J

NATURE

511

arranged that when the bob is swinging, and in the position of
maximum amplitude nearest the lens, the shadow o( a portion
of the wire immediately above the bob, thrown on a screen
some 32 feet distant, is clear and distinct, and coincides with a
vertical Mack line thrown on the white screen.

The bob is drawn back towards the lamp about eight inches,
by a loop of thread, and when we wish to experiment the
thread is then burned in the usual manner.

When the pendulum completes its first oscillation, the shadow
falls exactly on the black line traced on the screen. In about
five minutes the shadow has moved to the left of the line, and
in ten minutes conspicuously so. In this time the maximum
amplitude has decreased so little that the image on the screen
is still distinct and clear when the pendulum is in a position
nearest the lens. W. R. Westropp Roberts.

Trinity College, Dublin.

Snake Cannibalism.

HAVE read with interest the numerous accounts of snake

cannibalism which have lately appeared in Nature. During

n^y residence in South Africa, I have come across several in-

ilances of a similar nature. A few weeks ago I received a large

loughals {Sefcdon luemachate) which had swallowed another

cne of the same kind and of nearly its own length. As the sw.-il-

lowed individual was too long to disappear completely before

the front portion of its body was digested, its tail was sticking

cut of the mouth of the swallower by about six inches. I have

cissected two )ellow coVras (Naja haji), each of which had

swallowed a puff adder ( F//«rtar7V/a>M) more I ban three feet long.

This case is very interesting, as the puff adder has much larger

fargs Ihsn the yellow cobra, and in a fight the latter would

piobably succumb. To mention only one more case, I received,

:ome yeais ago, the skins of a cross-marked schaapsticker

[r.aninu'/his ouci/cr) and a spotted schaapsticker (/"Mmmc-

jltylax rhombiatiis), the former of which had swallowed the

latter. In all cases which have come under my personal obser-

^aticn ihe swallowed snakes had entered head first, and thus

] lobably they wtre simply drawn in after having caught hold

o( the same piey as the swallowers. In conclusion, I may men-

licn that cases similar to the above are frequently described in

'.he South African newspapers. J. SCHONLAND.

Grahamstown, South Africa, March i.

American Frtsh water Sponges in Ireland.

A SHORT lime ago, Dr. R. F. Scharff, Dublin, sent me a
.-mall colUclicn of Iri'h Spongillidae. The examination of the
nratciial resulted in the discovery of two or three American
species, obtained from the West of Ireland, viz. Hetercmeyctiia
lyJcti, Polts, lubella fcntnylvanita. Potts, and (?) Ephydaiia
aataijc) »n's, Polls, ihe fiisl of these three species having been
identified by Dr. W. Wcllner, Berlin. All these species are
r.ew 10 Euicpe, and as they were found in a small collection
taken mere cr less at rar.dcm, it is probable that if the fresh-
water fauna of ihe West of Ireland were thoroughly investi-
gated, a great many moie American species would be dis-
covered.

Details will be published in the May number of the Irish
Naliiralist. R. Hanitsch.

University College, Liverpool, March 13.

Peripatus in the West Indian Islands.

■West Indian records show that occasionally single speci-
mens of ^arious species of I'eripalus have been found in the
different islands. During the past week, Mr. Lunt, my
assistant, found a single specimen, and a further search being
organised, lesulled in the capture, by two collectors, of fifty
specimens. These, it is believed, belong to two different
species, and a goodly number of the specimens have been sent
for determination to the liritish Museum.

Either the animals are more numerous than usual, or the
previous search for ihem has not been a very careful one, as
the whole of our specimens were found within the precincts of
the Gardens. J. II. Hart.

Royal Botanic Gardens, Trinidad, March 6.

NO. 1326, VOL. 51]

Planetary Photography.

I understand that in photographing a planet, such as Mars,
only a short exposure can be allowed, because there is no way
of compensating the planet's a.na/ rotation. But, while follow-
ing the planet with the equatorial, would it not be possible to
compensate this axial movement by slowly sliding the plate, so
that certain features of the planet should fall always on the
same parts of the plate? If this is so, an exposure of some
lenglh might be available for the more central portions of the
disc, those portions for which, during the interval, no serious
alteration due to foreshortening comes into play.

Cardiff, March 23. C. T. Whitmell.

Cleaning Tobacco Pipes.

I HAVE discovered a new method for cleaning pipes which
have become foul. A shallow cork, through which a hole is
bored large enough to enable it to fit tightly on to the nozzle
of a soda-water syphon, i; fitted into the bowl. The nozzle is
inserted, the mouth-piece directed into a vessel, about a wine-
glassful of soda-water forced through, and the pipe is clean 1

This is not a scientific discovery, but it may be of use to
those scientific men who are smokers. Rubber stoppers answer
better than corks. Cecil Carus-Wii.son.

THE HABITS OF LI Af PETS.

SOME observations made by the present writer at the
Scottish Marine Station during July 18S4, were
published in N.vruKf: for January i, 1885. These obser-
vations confirmed the statements previously made by
various naturalists, from Aristotle onwards, that the com-
mon limpet (Patella vuli^ata) settles down on some
eligible spot (its " scar") between tide-marks, and makes
a home, to which it returns after havinfr been out to
feed. The conclusion was drawn from various data that
this " locality sense " is independent of smell, sight,
and touch so far as the head-tentacles are con-
cerned. Prof Lloyd Morgan, in a letter to Nature
(" Homing of Limpets," December 6, 1S94), has shown
that the limpet possesses an even greater power of
" homing'" than previous observers have suspected, and
he believes that the head-tentacles are the sense-organs
concerned.

Since 1S84, I have made further notes, and aided by a
grant from the Research Grants Committee of the Royal
Society, to whom my best thanks are due, have pursued
the subject with some care during the past year. The
results, apart from those connected with histology, here
follow.

The limpets observed live on a reef, which extends
several hundred yards seaw^ards (practically west) from
the front of Aberystwvth College. The rocks are
Silurian grits and imperfect slates, alternating in a very-
regular way, striking north and south, and tilted at high
angles. At low tide the Lamittaria zone is well exposed,
and for some yards above this the rocks are somewhat
bare, except that they are thickly encrusted with small
halaiii. Nearer the land various brown seaweeds
(mostly Fiicus scrratus. F. vcsiculosus, and Ozothallia
nodosa) thickly cover the reef, except towards high-water-
mark, where they become scanty. Throughout this area
limpets of all sizes abound, being specially numerous,
however, on the barnacle-encrusted rocks above men-
tioned. Groups of them were here marked with enamel
paint, and watched. A number of observations were
also made on the small limpet, which lives on Laiiunaria,
and has its shell marked by three diverging blue streaks
{Ih'ldon pellucidiim = Patella pellucida).

Food and Feeding. — As before, the chief food noticed
consisted of the minute alga- coating the halani and
rock-surfaces. Specimens were also found feeding on
the calcareous seaweeds Corallina and Melol'csia, on
Fi/ctis, and on Laminaria. It was suggested in Ihe pre-
vious notes that the great length of the radula is perhaps

;i2

NA TURE

[March 28, 1S95

correlated with the large amDunt of wear and tear en-
tailed by the constant " scrapinj " of birnicles, S:c. This
appears to be confirmsd by compirison with Hclcion,
ia which Ltminiria constitutes the chief, if not the only,
fojd, and in which the radula is relatively somewhat
shorter.

At Granton, in July, the larger limpets appeared to
feed most frequently ; but at Aberystwyth, during the
colder months, the small individuals are far more active.
Sheltered corners and warm days afford the best chance
of watching the movements. Though limpets undoubtedly
regain their scars, or secure places, as the tide advances,
I am inclined to think they must also often feed when
covered by the water, for (i) the finest specimens are
found low down, and their time for feeding when un-
covered is limited ; (2) I have seen a small limpet feed
on Corallina in a tide-pool.

The scraping sound heard on the rocks during warm
weather is not entirely due to feeding limpets. Purpura
lapillus is also busy at work " sawing out " balani from
their shells.

LocalitytSensc. — I still think./^ja* Prof. Lloyd Morgan,
that the head-tentacles are not indispensable to homing,
though it must be admitted that they may commonly
help in the process. One limpet observed homing by me,
certainly seemed to be " feeling '' its way along by means
of these organs, which were extended and waved about
and applied to the rock from time to time, not by the
e.xtreme tip only, but also laterally for about ,',. ot an
inch from this. This individual was No 2 of a small
group living among the barnacles, and kept under
observation from November 26 till the present time.
The dimensions of these limpets are as follows: — No.
1, 5" X i"; No. 2, ditto; No, 3, t" X § " ; No. 4,

rfr" X T; No- 5. ii' X

On November 2S, at

3.15 p.m., I found -No. 2 leeding iV' from its scar.
About half of each tentacle was excised (i.e. the part
previously noticed "feeling"), and the animal was re-
placed where found. On November 29, at 2.55 p.m., it
was found back on its scar. A similar operation was
performed on No. 5, found feeding 2'," from its scar, on
December 12, at 3.15 p.m. On my next visit, at 2.55
p.m. on December 14, the animal was found to have
regained its scar, which, by-theby, is permanently
submerged, being in a small tide-pool. It is true the
tentacles were not entirely removed, as was the case
with the two Granton limpets which homed after excision.
It now appears to me probable that the mantle-lcnlaclcs
may help m homing. These are small conical structures
lodged in pits in the mantle edge (Harvey Gibson,
Trans. R.S. Edin. 1885), and capable of retraction and
extension. About 100 of them are present. In sub-
merged limpets I have seen these tentacles protruded
for about ,',./' beyond the margin of the shell, and executing
active " feeling ' movements. These were particularly
noticeable in an individual which, having regained its
scar wrong end on, was shuftling round into the right
position. When the front end of the limpet came to point
in the right direction, one side of the shell was lowered,
and the mantle-tentacles on that side were withdrawn ;
the same events then happened on the other side.
These tentacles appeared to be of two kinds, longer and
shorter, the latter being two or three times as numerous.
Prof. Herdman first suggested to me that the mantle-
tentacles might have to do with the locality-sense, and
It at any rate appears probable that they are concerned
with accurate adjustment on the scar. It is worth
noting that very small limpets home as well as large
ones, e.g. No. 5 above, and much smaller ones which
have fallen under my notice. Prof. Lloyd Morgan's
observations, so far as they refer to knowledge of local
surroundings which limpets possess, are confirmed by an
experiment mide on No. 1. On December 16, at 4.5 p.m.,
thisanimil was basy scraping barnacles 3' west of its

NO. 1326. VOL. 51]

scar. It was removed and placed 10 inches from home,
near the top of a nearly vertical barnacled surface (on
which it had been seen feeding at 3,15 p.m., November
28), which rises north of its scar. The next visit was
deferred till December 26, 12.25 P-ni., when the limpet
was at home.

The homing faculty is not confined to Patella., but is
also possessed by Helcion peltucidum. This fact is new,
so far as I am aware. The animal in question eats out
a sheltered home in the bulb, or more rarely in the stalk
of Laininaria, and wanders out from this along the
thallus, rasping a " track " as it goes. I found, for
example, one individual at the end of an "eaten road "
3 inches long, and at the other end a very snug dwelling-
place drilled out in the side of the stalk. Helcion
mostly feeds under water. Like Patella, it possesses
mantle- as well as head-tentacles.

The object of homing appears to be protection from
the assaults of the incoming or outgoing tide. There is
no danger when the animals are completely covered or
uncovered. In many cases the barnacles would other-
wise completely cover the rock, and afford \ery insecure
foothold. Once washed loose, a limpet presents a very
large surface liable to injury, unlike its neighbour Pur-
pura lapillus, which, withdrawn into its thick operculated
shell, can stand a good deal of knocking about. The force
with which limpets adhere is illustrated by the fact that
the five small limpets to which allusion has been made
were quite uninjured by the terrible gale and high sea of
December 21 and 22, to which they v>ere fully exposed.
The much thinner shell of Helcion is explained by the
sheltered position of its home. The depressed conical
shape of a limpet-shell is probably better fitted than any
other to resist the waves, but this statement is made
under correction.

Formation of, and Adhesion to. Scars. — An'examination
of the 'tween-tide rocks at Aberystwyth w'ould readily
convince the most sceptical as to the power which
Patella possesses of excavating depressed scars. Lim-
pets are able to adhere very tightly to a smooth sur-
face which is much smaller than the foot, and by exam-
ination of such cases, and of specimens allowed to fix
themselves to a piece of plate-glass, I have come to the
conclusion that fixation is neither due to secretion of a
glutinous substance, nor to the formation of a vacuum
under the foot. It appears, in fact, to be a case of
" adhesion," like that between two smooth glass surfaces
brought very close together. The muscular foot is, so
to speak, rolled out on the rock, with which it is thus
brought into close contact. Prof. .Michael Foster sug-
gested to me the possibility of this method of explanation,
which is most probably the correct one.

J. R. AlNSWOKTH D.wis.

TERRESTRIAL HELIUM (.?).

WE have received the following statement from Prof.
Ramsay : —

" I have been trying for clues to compounds of argon.
Mr. Miers, of the IJritish Museum, called my attention
to Hillebrand's paper on Cleveitc, a rare Norwegian
mineral, which Ilillebrand said gave off 2 percent, of
nitrogen on warming with weak sulphuric acid. Cleveite
consists chielly of uranate of lead, with rare earths. My
idea was, if the so-called nitrogen turned out to be
argon, to try if uranium could be induced to combine
with argon.

" The gas, on sparking with oxygen in presence of soda
loses a trace of nitrogen, probably introduced during its
extraction ; the residue consists of a mixture of .Argon
and Helium ! The brilliant yellow line, of which Mr
Crookes makes the wave-length 58749, is identical with
the Helium line. I am collecting the gas, and shall
shortly publish regarding its properlies."^

March 28, 1895]

NATURE

51;

NOTES.
The Bakerian Lecture will be delivered before the Royal
Society on Thursday, May 9. The research upon which the
lecture is to be based has been coodu;ted by Messrs. A. Vernon
llarcourt and William Esson, and the title is announced as
" The Laws of Connection between the Conditions of a Chemical
Change and its Amount."

An abstract of the paper in which M. Berthelot describes
his investigations of chemical combinations with argpn, will be
found in our report of the meeting of the Paris Academy of
Sciences (p. 527).

Prof. Adolphe Car.not has been elected into the Paris
Academy of Sciences, in the place of the late M. de Lesseps.

The late Mr. William Bolitho, of Gulval, Cornwall, has be-
queathed £,yx> to the Geological Society of Cornwall, the in-
come of which sum is to be applied each year in " the production
of a gold or richly-gilded silver medal, to be presented to the
member of the Society whose attainments, labours, or dis-
coveries in geological or mineralogical science are found most
deserving." He has also left a like sum for the Penzance
Library.

The death is announced o Mr. E. Turner, Chairman of the
I ouncil of the Sanitary Institute.

We also notice the death of Dr. E. D. F. Meissel, at the age
of si.Kty-nine. He made a number of important contributions
■ mathematical astronomy, and his tables of Elliptic Functions,
a, well as the table of Bessel's Functions, published in the
Ahliandlun»cn of the Berlin .-Vcademy, stand as examples of his
work.

Mr. H. H. Haytek, C.M.G., the well-known statist, died
.It Melbourne last week. He was the first president of the
economic and social science section of the Australasian Associa-
I tion for the Advancement of Science. His numerous and
1 valuable statistical publications earned for him the honorary
membership of statistical societies in various parts of the
world.

Dr. Canini, of Leghorn, a well-known Italian specialist in
diseases of children, who died recently, has, says the British
Aledical fournal, bequeathed his entire estate, amounting to
2,300,000 lire (^92,000) for the foundation of a hospital in
which poor children suffering from diphtheria may have the
advantages of the serum treatment gratuitously.

I We take the following news from the same source : — The late
Dr. .\lfred L. Loomis, of New York, has left real estate to the
value of 400,000 dollars (jf8o,coo), and personal property
.imounting to 600,000 dollars (;^i20,ooo). The income of

125,000 dollars (.^5000) is given to the Loomis Laboratory, and
whatever p,irt of the income is not used is to be paid to the
Professor of Pathology of the University of New York. A sum
of 10,000 dollars (;{^2000) is beiiueathcd to the New York

I Academy of Medicine, the bequest to be known as the Loomis
Entertainment Fund, and the interest to be used in providing
entertainment for the Fellows of the Academy.

M. Nils Eikholm, who was at the head of the Swedish
astronomical and meteorological expedition for observing the
{transit of Venus in 1S82, has accepted a place in the Andrce
balloon, which is to start from Spitzbergen for the North Pole in
July 1896. The ascent is to take place from Norskoarna,
the distance from which to the North Pole is about 600 miles.
But it is not e.xpected that the balloon will travel in a direct
line. M. Andrce will visit France in July next, and he will

NO. 1326, VOL. .i^l]

probably be present at the Ipswich meeting of the British>

.Association.

Dr. ^L K. Veeder writes: " In the table of 'Days with
maximum temperature not over 32' at Greenwich,' on page 17+
of Nature (February 28), the curve rises sharply and decidedly
at intervals of exactly twelve years — namely, in 1S54, 1866,
187S, and iSgo. These years also fell in the well-known
period of sun-spot and auroral minimum, but did not comprise
the entire periods of such minimum in each case. There seems
to be a clue here that is important, and that is in a line with
the study of current phenomena of this sort in which I have
been engaged, some of the results of which were presented in a
paper entitled ' Periodic and Non-Periodic Fluctuation in the
Latitude of Storm Tracks,' read at the Chicago Congress of
Meteorology in 1893."

The following are among the lecture arrangements at;
the Royal Institution, after Easter: — Prof. George Forbes,
three lectures on " .Alternating and Interrupted Electric
Currents" ; Prof. E. Ray Lankester, four lectures on "Thirty
Years' Progress in Biological Science"; Prof. Dewar, four
lectures on "The Liquefaction of Gases"; Dr. William
Huggins, three lectures on " The Instruments and Methods of
Spectroscopic .\stronomy " (the Tyndall Lectures) ; Mr.
Arnold Dolmetsch, three lectures on " Music and Musical
Instruments of the Sixteenth, Seventeenth, and Eighteenth
Centuries : I. English ; 2. French ; 3. Italian " (with illustra-
tions upon original instruments). The Friday evening meet-
ings will be resumed on April 26, when a discourse will be
given by Dr. John Hopkinson, on " The Effects of Electric
Currents in Iron on its Magnetisation." Succeeding discourses
will probably be given by the Earl of Rosse, Veterinary-
Captain Frederick Smith, the Hon. G. N. Curjon, M.P., Mr^
J. Viriamu Jones, Prof. Alfred Cornu, and other gentlemen.

A STRONG earthquake shock was felt at 1. 16 p.m. on Satur-
day last at Comacchio, in the province of Ferrara, Italy,
Several houses and a church were slightly damaged. At
Mirabella Imbaccari, in the province of Catania, in Sicily,
the earthquake caused the collapse of a building.

Dr. B. BRAtJNER, Professor of Chemistry in the Bohemian
University, Prague, suggests to us that argon possibly exists in
nebulae. He points out that a strong argon line, measured by
Mr. Crookes, has practically the same wavelength as the chief
nebula line, and thinks that the line at A. 3729'S in the " blue"
spectrum of the new substance represents the ^line at \ 3730,
found in the spectra of nebulje and white stars.

Herr W. Siebe has started on a botanical exploration of
Asia Minor, with the special object of making collections of
the almost unknown ilora of Cilicia Trachea. Setting out from
Cyprus, he proposes to visit Mersina in southern .Asia Minor,
proceeding then to the Kalykadnos Valley and the adjacent
mountains, the steppe-district of Konia, the maritime district
of Egerdir, and finally, in the summer, the elevated alpine
region of Geigdagh.

A STORM of unusual severity passed over these islands on
Sunday last. At Sh. a.m. on that day it was central over the
sout h of Ireland, and by 6h. p. m. of the same day the centre had
reached Denmark, having traversed a distance of 600 miles in
ten hours, which gives an average rate of progress of sixty miles
an hour. Much damage was done to life and property over the
whole country ; but its greatest violence was felt over the
southern and midland counties. The maximum force at Green-
wich was at 2h. 20m p.m., when the anemometer registered a

514

NATURE

[March 28, 1895

■pressure of 36 lbs. on the square foot, which is equivalent to an
hoorly velocity of eighty-five miles. Thunder and lightning
occnrred at several places in the rear of the disturbance.

The project of a great free public library in New York
City has just taken shape, and been adopted by the several per-
sons and boards of trustees interested. It contemplates the
union of the Astor, Lenox, and Til den funds, aggregating
8,000,000 dollars. The site of the library is not yet determined,
owing to some restrictions on the use of the block facing Central
Park, on which the Lenox Library now stands. This site is
preferred if available. Boston, with its 5,000,000 dollars free
library, just completed, has already taken the lead. Brooklyn
has in the library of the Pratt Institute the nucleus of an
admirable free library, for which a new building is nearly
ready.

We are glad to learn of the continued growth and develop-
ment of the Brooklyn Institute, due in great measure to the
stimulus imparted by the Brooklyn meeting of the American
Association for the Advancement of Science List summer.
Since that time the membership of the Institute has increased
many hundreds, bringing it up to very near four thousand, and
making it one of the largest scientiAc associations in the world.
Plans for a new building and museum, to cost several million
dollars, have been for some time ready, and only await funds.
Probably work will begin during the present season. The site is
secured, and it is hoped that aid from the city will be obtained as
soon as the condition of finances justify it. Meanwhile the Insti-
tute, in its geographical section, is foremost in promoting far-
'eaching plans of exploration toward both poles. Besides the
arctic expedition mentioned in NATitRE last week (p. 48S), a
well-digested plan for antarctic exploration has been presented
by Dr. Fred. A. Cook, who is already familiar with travel in
the north. He proposes to start next. September, equipped fora
slay of three years, but with the intention of returning in two
years unless accidentally detained. It seems probable that the
expense of the expedition will be provided for, and that it will
be the best equipped that has ever ventured into that region.

I.s the February and March numbers of the Geological
Magazine, Miss Agnes Crane gives an account of the results
of recent research on the geological distribution of the Brachio-
poda, and their bearing on the evolution of the group. The
si mple I'at'.riua of the Cambrian is regarded as the actual root-
stock of the group, and the descent of the chief lines is traced
from it, with some breaks here and there i from'imperfection of
knowledge. According to Beecher, almost all Brachiopoda
pass through a "patcrine" stage of development. I.itti^uhi,
which (in the proper generic sense) does not occur below the
Ordovician, passes in its development through a stage
in which it resembles its predecessor ObeUlla of the Cam-
brian, and the latter is said to have a transient "paterine"
stage. Terebrattiliiia is also stated to pass through a " lingu-
loid " stage, yet its branch is not regarded as derived from
Lingiila, but independently from Pateriiia. Numerous other
genera are dealt with, and the paper is illustrated by two plates,
one giving the genc.ilogic.il tree of the Brachiopoda, and the
other some examples of the relation of forms.

There is an interesting note in the Rultelin of the Royal
Gardens, Kew, on the use of green glass in phnt-houscs. The
use of glass of a green tint has hien for half a century a
charac'.eristic peculiarity of the plant-houses at Kcw, having been
adopted in 1845-46 on the recommendation of Mr. Robert
Hunt, F. K.S., on the ground that while admitting light and
chemical power in the same proportions a? white glass, it
would obstruct the passage of those rays which produce scorch-
ng. Recent investigations h.ive, homvcr, shown that the
NO. 1326, VOL. 51]

green glass used at Kew intercepts about one-half of the eft'ective
influence of ordinary sunlight on the processes of plant-life. Of
late years the increasing haziness of the sky, due to the smoke
produced by the rapid extension of Londonto the south-west, has
produced the same effect at Kew as the use of green gl.iss; and it
has become obvious that in the future the plant-houses must be
so constructed as to exclude as little of the available sunlight as
possible. Since 1SS6 the use of green glass has, therefore, been
discontinued in all the houses except the fern-houses and the
palm-house ; and, it having been proved by experiment that
even filmy.ferns thrive better under white than under green
light, if direct exposure to the sun is excluded, the use of green
glass will now be altogether abandoned at Kew.

The action of light in producing an electric discharge through
a vacuum tube has been further investigated by Messrs. Elster
and Geilel, who communicated some very suggestive results to
the Berlin .Academy at a recent sitting. They used a " photo-
electric cell," consisting cf an exhausted glass globe with an
anode of platinum wire and a kathode of an alloy of sodium
and potassium in equivalent proportions, which is liquid at
ordinary temperatures. This alloy was illuminated by a beam
of white light from a piece of zircon rendered incandescent by
an oxy-coal gas blow-pipe flame. This was condensed and
made parallel, and then sent through a Nicol prism so as to
polarise it in a certain plane. It was then found that a current
passed through the cell on connecting its terminals with a bat-
tery giving some 400 volts. The strength of this current
depended very much upon the angle of incidence and upon the
plane of polarisation. It was greatest when the plane of
polarisation was perpendicular to the plane of incidence, i.t.
when the electric displacements constituting light took place in
the plane of incidence, and when the angle of incidence was 1
about tSo", i.e. the polarising angle of the alloy itself. The
phenomena have probably some connection with the fact dis-
covered by Quincke, that light polarised normally to the plaoe I
of incidence penetrates furihest into metallic sheets. I

Ol- late years' the transmission of electricity through gases
has been attracting a considerable amount of attention, and
numerous papers have appeared dealing with this subject, one
of the last being by G. Vincentini and M. Cinelli. Their
paper, which appears in the Nui.no Cimenio (5) vol. xxxvi., deals
with the transmission of electricity through the g.is surrounding
a wire heated to redness by an electric current. The authors
first describe experiments they have made on a long platinum
wire surrounded either by air or carbon dioxide. The wire was
protected from draughts by a series of screens, and a movable
platinum electrode, connectcil to a quadrant electrometer, gave ,
the potential of the air at different distances above and below
the heated wire. It was found that the potential assumed by the j
electrode connected to the electrometer was higher than the mean ,
potential of the he.ited wire. When the current passed through
the wire was sulliciently intense to heat it to incandescence, the
potential of the insulated electrode when placed above the wire
did not vary with the distance from the hot wire to any sensible]
extent.'only the maximum electrification was attained at difl'erenl '
times after starling the current, and the greater the distancej
from the liotjwirc the greater the lime which elapsed before the I
steady state was reached. When, however, the insulated elec-l
trodc is below the incandescent wire, the difference of potentilH
decreases very rajiidly with the distance, so that at 15 m.m. iti
almost vanishes. In order to cair)' on observations on otbert;
gases besides air and carbon dioxide, the authors have devised a^
modified form of aiipaiatus in which Ihe incandescent wire \t^
placed inside a globe w hich is silvered on the inside. This globe/
has fourlubuli, Iwo of which serve for thcinlroduclionof Iheelec-j
Irodes for the hot wire ; while of the remaining two,|one adiDltlJ
the insulated electrode, and the other a wire which is connected to

March 28, 1895]

NA TURE

515

the silvel- coating of the globe, and serves to put this to earth.
The authors consider that their experiments show that the gaseous
molecules which leave the surface of the incandescent platinum
wire in the case of hydrogen are positively electrified, their
potential being about 025 volt higher than the mean potential
of the incandescent wire. In the case of air and carbon dioxid e
the increase above the mean potential of the wire is about one
volt. With hydrogen at a somewhat high temperature an in-
version of the phenomenon takes place, since the potential of
the insulated electrode becomes less than the mean potential of
the wire.

A NEW phototheodolite is described by Herr O. Ney in the
Zeilschrijt fiir Instrumentekiiiindi. The novel feature about
it is the geometrical clamp, which enables the surveyor to ex-
change the telescope and the camera on the stand with ease and
accuracy. Both are provided with three spherical feel, which
rest in a hole, a slot, and a plane respectively, madeofhaid
steel, and fixed on the stand. This seems an admirable way out
of the difficulty attending the simultaneous use of telescope and
camera. Other instrument-makers combine the two by mount-
ing a telescope at the side of the camera, with a counterpoise
on the other side. In one instrument the telescope lens is also
used for photographic purposes. But these instruments are
either too small, or the adjustment is exceedingly unstable. In
Ney's phototheodolite, which is made chiefly of aluminium,
provision is made for securing the camera or the telescope on
the stand after it is mounted in the hole-slot-and-plme clamp,
and also for the constancy of the position of the sensitive plate.
With these improvements, the instrument is likely to become a
most valuable aid to surveying practice.

Dr. C. G. de Dalla Torre's useful "Catalogus Hymen.
opterorum " continues to make satisfactory progress. It is pro-
posed to complete it in ten octavo volumes, exclusive of biblio-
graphy and in-iex, which will form a separate volume ; and five
volumes have already been published, including vol. i, Tenthre-
diniJ.c and Uroceridu ; vol. 2, CynipiJ.,-. vol.6, Chryiidida: ;
vol. 7, I'ormicidiz ; and vol. 9, J'espidir. The remaining families
may be expected to follow shortly. The subject of entomology
is so vast that little progress can be made without some ento-
mologist from time to time devoting his life to the compilation
of these great key-catalogues, which are landmarks in the study
of tlie orders of which they treat, and stand towards them in
the same relation as a dictionary to a language. Moreover,
such catalogues involve an amount of patient and unremitting
toil that no one can appreciate who has not himself experienced
it ; they are frequently published at a heavy pecuniary loss, and
are peculiarly liable to criticism, which may be fair and friendly
in tone, or may be just the reverse. Let us hope that Dr.
Dalla Torre's labours will meet with the encouragement which
he deserves from the hymenopterists, whose labours he has so
much contributed to lighten.

The discovery of the use of fire d.ates back to the very dawn
of human intelligence ; therefore the study of the rites and
ceremonials which are found among every race in connection
with the lighting of new fires, furnishes important facts for the
discussion of the primitive history of human culture. But be-
fore it is possible to .ipply comparative methods of treatment to
the subject, exact observations are required of the details of the
new fire ceremony, wherever it survives, especially in less modi-
ned, savage, or primitive peoples. This requirement is fulfilled
by an article, by Mr, J. W. Fewkes, descriptive of the new fire
ceremony as it exists among the Pueblo Indians of Tusay.in
/tosU'ii Soc. A'al. //«/., vol. xxvi. pp. 422-45S, Feb. 1895). Mr.
Fewkes watched two such observances of the Tusayan Indians,
)ne in 1S92, and the other in 1893. In both years active cerc-
nonials began on November 13, and continued five days. Two

NO. 1326, VOL. 51]

other days, November S and 9, were devoted respectively to-
"smoke assembly " and "official announcement," and Novem-
ber i8, when all serious ceremonials had ceased, was a general
holiday. On each of the five days, from November 13-17,
various processions and rituals were observed, in many of which
the element of phallic worship plays a not inconspicuous part.
It is unnecessary to describe these performances, but one or two
remarkable points in connection with the dates on which they
take place, are of interest. The Tusayan Indians, says Mr.
Fewkes, can neither read nor write, and are ignorant of our
almanacs and calendars, nevertheless they manage to make the
performances commence on the same date, within a day or two,
every year, the time of year being obtained by observation of
the stars. Another instance of the astronomical knowledge of
such rude people as the Tusayan Indians, is afforded by the fact
that the culmination of the PliiadiS is used to determine the
proper time for the beginning of certain rites. This is a further
example of the widespread use of the Pleiades for the determin-
ation of the time for the celebration of primitive rites and
ceremonials.

It may interest our readers to know that a catalogue of the
more important books published in Denmark and Norway
during the year 1S94 can be obtained from the Skandinavisk
Antiquariat, 49 Go'.hersgade, Copenhagen. The catalogue
contains the titles of a number of important works on various
branches of science.

A NEW volume, containing the Biological Lectures delivered
at the Marine Biological Laboratory, Woods Holl, in 1894,
will shortly be published by Messrs. Ginn and Co. The lectures
cover a wide range of subjects, most of which are proaiinent
questions at the present time, and all of which are of special
interest to teachers and students of biology.

Mr. R. F. Stupart, the new Director of the Meteorological
Serviceof Canada, has commenced the publication of a mDnthly
weather map, showing the mean temperature and the difference
from the mean average temperature, also total rain and snow-
fall for the month, and depth of snow on th; ground on the
last day of the month. It is interesting to note that an extremely
cold spell prevailed over Ontario in the early part of February,
some of the low readings being almost unprecedented.

Mr. H. W. Wiley, the chem-st to the United States De-
partment of Agriculture, recjm Beads the cultivation of the
cassava, Manihot u'.ilissima, in the most southerly of the
United States. It furnishes an excellent food for men and for
cattle ; though, from the small proportion of nitrogen which it
contains, it cannot t.ike the place of bread-stuffs. A very good
kind of tapioca may be made from it. The yield, in sandy
soils, is from four to five tons per acre.

A COLOURED map, showing the density of the popuUtion of
Ireland at the Census of 1891, has been prepared and pablisheJ
by Mr. E. E. Fournier, Bray, Ireland. The map exhibits at a
glance the density of the population, and shows clearly that
some of the oldest railways have had a beneficial iniiaen:e in
preserving or increasing the population of the districts thrjagh
which they run. It is the first of a series intended to exhibit
graphically the physical, social, economic, and religious features
of Ireland.

" The Statesman's Year-Bjok " (Macmillan and C:).)— that
handy compendium of statistical and historical informition
relating to all the States of the world— has attained its thirty-
second year of publication. Edited by Mr. J. Scott Keltie,
with the assistance of Mr. I. P. .\. Renwick, the volume is a
standard work of reference in which the man of business can
find the commercial statistics he needs, to which the politician
can apply for trustworthy statements, and from which the

5i6

NA TURE

[March 28, 1895

student of geography can obtain the latest geographical in-
formatioa.

Dr. a. E. Me\xr, of the Royal Zoological Museum at
Dresden, has sent us a description of two new bird? of paradise
from New Guinea. {Abk. u. Ber. d. K. Zool. ii. Anthr.-Elhn.
M:is. zu Drt:den, 1894-95, No. 5). One of the birds, shown
in its natural size in one of the two coloured plates which
illustrate the paper, possesses remarkable ch.iracteristics in the
form and colour of its plumage, and in the arrangement of two
very long feathers which stretch out from the head to about twice
the length of the body of the bird. This bird has been named
Pteridophora alherti, in honour of King Albert of Saxony, and
the second one described and figured by Dr. Meyer has been
called Paro'.ia carolts, after Queen Caroline.

The seventh volume of the Proceedings of the Royal Society
of Victoria has reached us. The volume contains twenty-eight
papers, many of them illustrated with plates, communicated to
the Society during 1894. With two or three exceptions, the
papers belong to the domain of natural science. Among the
contributions we notice one on Tasmanian earthworms, by
Prof. Baldwin Spencer, and a note, by the same author, on two
new forms of marsupials obtained in Central .\ustraUa, during
the visit of the Horn Scientific Expedition to the Macdoanell
Ranges. The geology of Castlemainc is described by Mr. T.
S. Hall, and geological notes on the country between Strahan
and Lake St. Clair, Tasmania, arc contributed by Messrs.
Graham Officer, L. Balfour, and E. G. Hogg. The older
tertiary rocks of .Maude, and the paleontology of the older ter-
tiary of V'ictoria, form the subjects of two separate papers, and
a catalogue of non-calcareous sponges collected in the neigh-
bourhood of Port Phillip Heads is given by Prof. .\. Dsndy.
Mention must also be made of a paper, by Mr. R. H. Mathews,
on rock paintings and carvings figured by the Aborigines of New
South Wale;, in caves and rock shelters ; and also of one in
which Mr. E. F. T. Love gives the results of observations with
Rater's invariable pendulum, made at Sydney. The object of
this investigation was to throw some additional light on the
question of the difference between the values of ^^ at Melbourne
and Sydney. .\ comparison of the results obtained by the
United States Coast Survey oflScers at Sydney in 18S3, with
those found by Mr. Baracchi at Melbourne in 1S93, has shown
that a pendulum beating seconds approximately should lose
8-58 vibrations per day, if transferred from Melbourne tu
Sydney. Lieut. Elblein found, however, by swinging three of
von Stemeck's pendulums at the two places, that the loss was
I3'48 vibrations per day. Mr. Love comes to the conclusion
that the difference between the vibration numbers at Melbourne
and Sydney is 12-2 per day.

Tmk additions to the Zoological Society's Gardens during the
past week include a Sand Badger {i1/<r/« <j«4«/«a) from Japan,
presented by Mr. Frederick Ringer ; two Polar Bears ( Ursus
marilanus, i 9 ) from the Arctic Regions, presented by Mr.
John J. Hughes; a Spotted lIy.T;na {Hyu:na crocuta,\\.), a.
Vociferous Sea Eagle (l/aliaeltis vocifer), a Black Kile
(Mill us mi^an), horn East Africa, presented by Mr. T. E.
C. Remington; a Black-backed Piping Cxoii (Gymiiorliina
liiicieii) horn Australia, presented by Mr. J. V. Haggard;
a Raven {Cjri'us corax) British, presented by Mr. W.
Hillary; a Puff Adder (Vipera arielaus) from East Africa,
presented by Dr. A. Donaldson Smith ; a Chimpanzee
{AnthropopitlucHS trogladyles, 9 ) from West Africa, a
Common Marmoset {f/npale jcuchm) from South-east Brazil,
deposited ; a I'urplc-brcasted Lory {Eos rieeiiiala:) from
Moluccas, a Blue-faced lloaey-csAcr (Entomyza cyanolis) from
Australia, purchased.

NO. 1326, VOL. 51]

OUR ASTRONOMICAL COLUMN.

The Moon and Atmospheric Waves. — Lunar atmospheric
waves, or air-tides, as they might be called, can, according to
M. Bouquet de la Grye, be .lislinctly traced in the records of
barometric pressure collected at insular stations or stations
situated close to the sea, where there are no powerful local
disturbances to obscure them. In a contribution to the
Annuaire dtt Bureau des Loti^tudes., he reproduces curves of
atmospheric pressure traced at Brest, St, Helena, Cape Horn,
Batavia, and Singapore, which distinctly show a regular ebb and
flow twice a day in accordance with the position of the moon.
The amplitude depends upon the declination of the moon and
upon its distance from the earth, and also upon the latitude of
the place of observation. The maximum amplitude at Brest
is about a quarter of an inch of water, which means a fiftieth
of an inch of mercury, a small oscillation indeed, but one
which is well within our limits of accurate measurement. At
Batavia the maximum heights are hall an hour after the passage
of the moon through the upper or lower meridian. But the
retardation is almost imperceptible in other places. This is
probably due to the extreme mobility of the upper strata of the
atmosphere, and contrasts with the great retardation experienced
by the ocean tides. M. Bouquet de la Grye points out the
striking analogy between the ocean tide, with an amplitude of
I m. under the equator, in an ocean having a mean depth of
5000 ra., and the atmospheric tide of 2 mm. of water in a sea
of air the weight of which represents 10,000 mm. of water.

Stellar PHOTOGRArHV. — A remarkable illustration of the
value of photography in astronomical researches is afforded by
a recent comparison of one of Dr. Max Wolfs well-known
photographs with the same part of the sky as seen with the
36- inch refractor of the Lick Observatory. Piof. Schaeberle
finds that an enlarged photograph of the region about Algol,
taken with an exposure of five hours, certainly shows stars down
to mag. 165, assuming that stars of the 17th mag. are at the
limit of vision of the telescope. Making due allowance for
the loss of detail in the process of enlarging, " it appears pro-
b.-ible that practically every isolated star visible at Mount
Hamilton can be photographed by Dr. Wolf, at or near sea-
level, with his comparatively small telescope.' (Aslronomical
Journal, No. 338). The telescope employed by Dr. Wolf has
a Voigtiander lens of six inches aperture.

Standard Time in Australia. — The resolution as re-
gards Australian standard time, adopted at Melbourne last
October (see p. 278), has come into cOect. Queensland, New
South Wales, Victoria, and T.ismania .ire now all using the
time of the meridian- 150° E., th.it is, ten hours before Green-
wich. Queensland was the first of the Australian colonies 10
take action, and there the new time caiue into force on the first
day of this year. Mr. H. C. Russell, of Sydney Observatory,
has sent us a copy of the .\ct which established the mean lime
of the meridian 150° E. of Greenwich as the standard time in
New South Wales, on and after February i. He says that
" South Australia has adopted the time of the ninth hour before
Greenwich."

Nova Aurig.e. — Notwithstanding the enormous velocities
in the line-o(-sight recorded by the spectroscope, Nova Aurig.T:
has given no signs of proper motion, such as can be perceived
with the telescope and micrometer. Such, at least, is the result
of a comparison of the measurements made in 1S94 by Prof.
Barnard with tho-e made by the same observer in 1893, and by
Mr. ISurnham in 1892. [Asl. Nach. No. 3279.) The magni-
tude also remains pretty constant, being I0'5, on the scale
adopted at the Lick Observatory. The Nova seems to be too
far removed from our system to give any appreciable parallax.

NEW COMPOUNDS OF HYDRAZINE WITH
FATTY ACIDS.

COMPOUNDS of several of the more important organic
fatty acids with bydiazine, analogous to the aromatic
hydrazidcs previously prepared, have been oblaintd by P™.
Curtius and his pupils Messrs. Sch.'fer and Schwan, and M
account of them is published in the current issue of the Journal-
jiir Prakliiclit Chemie. The hydrazides of the monobasic fatly

March 28, 1895J

NATURE

517

aciils are di'tinguished from the aromatic analogues by their
greater solubility in water. In all cases they are most advan-
tageously prepared by reacting with one equivalent of hydrazine
hydrate upon the e-ler of the acid rather than upon the free
acid itself. The ei.ters of dibasic fatty acids react analogously
with two equivalents of hydrazine hydrate, producing hydrazides
which contain two NHNH groups.

Formic hydrazide, HCO.NHNH.^, is produced when mole-
cular equivalents of ethyl formate and hydrazine hydrate are
mixed, considerable evolution of he.it occurring. When the
product is allowed to stand in a vacuum for some days large
tubular crystals of the pure compound 'eparate. The crystals
are transparent, very hygroscopic, and extremely soluble in
water, alcohol, ether, chloroform, and benztne. They melt at
54°. Formic hydrazide does not form salts with acids ; even
dilute acids at once decompose it in the cold with formation of
formic acid and a salt of hydrazine. The solution of the crystals
in water reduces Fehling's solution and ammoniacal silver
nitrate readdy at the ordinary temperature. Formic hydrazide
forms a crystalline compound with benzaldehyde with consider-
able rise of temperature and with elimination of water.
The crystals of the compound, benzalformyl-hydrazine,
HCO.NH.N : CH.CJI;, melt at 134°. When excess of ethyl
formate is heated with hydrazine hydrate in a sealed tube to
100"- 1 30' for some hours, another formic hjdrazide, diformyl-
hydrazine HCO.NH.NII.COH, is produced in the form of
brilliant colourless prisms an inch or more in length. In the
prep.iration of this beautiful compound care must be taken to
strongly cool the tube during the filling with the two compo-
nents, as their interaction is otherwise of a dangerously ener-
getic character. The crystals of diformyl-hydrazine are very
soluble in water, but difticuUly so in alcohol, and practically in-
-solubla in ether. They melt at 159°, and reduce ammoniacal
silver solution upon warming. Dilute sulphuric acid decom-
poses them as readily as those of formic hydrazide into formic
acid and hydrazine sulphate.

.Vcetic hydrazide, CH3.CO.NH.NH.,, is prepared by warm-
ing equivalent quantities of acetic ether and hjdrazine hydrate
in a sealed tube for a few hours at llie temperature of a water-
bath. The product rapidly solidifies in a desiccator to a white
mass of crystals. The crystals are colourless needles aggregated
in leaves, and melt at di". They deliquesce rapidly on exposure
to moist air, and are also very soluble in cold alcohol. The
aqueous solution reacts neutial to litmus, and is readily de-
composed into the original component substances by either acids
or alkalies. The compound cannot be distilled without decom-
position. The solution reduces Fehling's solution very vigor-
ously on warming. Like the formic compound, acetic hydra?:de
reacts with benzaldehyde to produce an analosous crystalline
compound, .icetyl-benzal-hydrazine, CH3.CONHN : CHCuH,.
CO.NH.NH3

Oxalic hydrazide, | , is produced by the action

CO.NH.NH.,
of two molecular equivalents of hydrazine hydrate upon ethyl
oxalate. The reaction is a somewhat violent one, and is best
moderated by the addition of a little alcohol.

The new compound separates as a white crystalline mass,
which is much less soluble in water than the hydrazides of the
monobasic acids, and is almost insoluble in alcohol and ether.
It is deposited from solution in hot water in very long and thick
needles, which decompose at 235°. The solution reduces
Fehling's or ammoniacal silver solution much less vigorously
than the monobasic compounds. Oxalic hydrazide is much
more stable towards acids and alkalies than the last-mentioned
substances. The compound may be recrystallised unchanged
from dilute sulphuric acid, and concentrated sulphuric and
hydrochloric acids only decompose it very slowly. If, however,
concentrated hydrochloric acid is allowed to drop upon the
powdered substance moistened with water, until the acid is in
slight excess, a white crystalline powder is obtained which is
found to consist of the hydrochloride of the hydrazide,
CO.NH.NHj.HCl

I . Oxalic hydrazide reacts in an interesting

C0.NII.NH„.IIC1

manner with nitrous acid (sodium nitrite and glacial acetic
acid) ; an energetic evolution of gas occurs, and a white powder
separates. The same white substance may be obtained by
acting upon oxalic hydrazide suspended in water with mercuric
oxide, and decomposing the mercury compound produced with
sulphuretted hydrogen, the filtrate depositing the white powder

NO. 1326, VOL. 5 l]

upon evaporation. Analysis indicates that the compound

CO— NH
probably possesses the constitution, I |

CO— NH
CHj-CO-NIINHj
Succinic hydrazide, | ' , is prepared similarly

CHJ.CO.NHNH2
to oxalic hydrazide, and crystallises in silver-like crystal aggre-
gates which melt at 167', and which are more soluble in water
than the crystals of oxalic hydrazide. Malonic hydrazide,

/CONHNHj
CHj<^ , is likewise obtained in a similar manner,

^CONHNII,
the reaction between malonic ether and hydrazine hydrate
being very vigorous even in the cold. The crystals melt at
152°. The aqueous solution reduces Fehling's solution, am-
moniacal silver solution, and platinic chloride at the ordinary
temperature. Both the succinic and malonic hydrazides are as
stable towards acids as the oxalic compound, and each yields a
hydrochloride with concentrated hydrochloric acid. Both
hydrochlorides are obtained in the form of small crystals, and
they melt at 203 and 197° respectively with violent evolution
of gas. Succinic hydrazide reacts with nitrous acid to form an
interesting compound analogous to that of oxalic hydrazide.

CH„.CO.NH
Its simplest possible constitution is | | .

CH..CO.NH
Several other more complicated hydrazides are described in
the memoir, but the above will afford a sufficiently compre-
hensive idea of the important addition to our knowledge of the
hydrazine compounds which we owe to the la''.ours of Prof.
Curtius. A. E. TuTTON.

THE AURORA OF MARCH 13.
A NUMBER of letters referring to an aurora observed on
"^ March 13, have reached us. We select from these com-
munications a few de'ails of value and interest.

Writing from \'ork, Mr. J. Edmund Clark says : —

" I was in a position for observing at 9. 10 ; the display finally
ended soon after 10. The latter part was seen, very similarly, at
Scarborough, 9.10. Arch, pure white (and so all through) just
north of zenith ; east end brighter, with well-defined, beak-like
apex upon o Corona; borealis (alt. 17% az. 13° north of
cast). Upper edge just grazed t," and tj Ursx majoris,
the lower some 3'' below Polaris, a little west of which it
became double, the Pleiades lying in the fork, 5^ or 10' from the
finish at about altitude 20° or 25°, nearly due west. No auroral
glow outside, nor later, except as stated. The outer curves,
west end, would have met, if continued, in similar "beak " as
at east end.

"9.15.' Lower edge through 3 Ursae minoris, Polaris, and
o Persei. Streamers now traversing rapidly from tatt to -.vest,
pointing to magnetic anti-pole ; passed from ij Ursse majoris to
Polaris in 25 to 30 seconds by watch. Constant succession, as
bars of light, for some minutes ; then temporary cessation, but
later intermittent, until 9.45. These were entirely distinct, as
is obvious, from the ordinary far more rapid flickering from
horizon t(5 magnetic anti-pole. Three rough positions of
stationary forms near the Plough, Auriga, and Jupiter, pro-
jected on the B.A. Meteor Star Chart, cross at altitude 6S.y',
azimuth 35" (\' and 6^ respectively from the true magnetic anti-
pole, for York, at 68^ and 18°).

" 9.25. Streamers, often as curtain-like fringe on lower edge
of arch, now less prominent. Otheis still streaming from east
to west in the arch show no perceptible efTect as they sweep by
these. New set moved slowly westward, about I* or 2° per
minute.

"g. 30. Lower edge again as at 9.25. Upper edge had
covered Plough ; arch double more or less entirely ; varies
fast ; much fainter to east from 9.25.

"9.37. Lower edge through handle of Plough, Capella, I*
north of M.rrs and % on from Mars to horizon. Fringe below
now brilliant, but rapid fluctuations.

" 9.45. Brilliant short streamers in fringe, from Mars to
a Auriga-, and ', on to Polaris.

" lo.o. All gone but one long faint streamer from 3° to left

1 If other* have thoueht of recording positions .it the exact quarters, some
altitudes migtit t>e obtained from the four given here.

NATURE

[March 28, 1895

of Aldebaran up lo l' to left of Japiter, moving slowly west-
wards a< before."

Mr. G. W. Lamplugh observed the display at Ramsay, Isle
of Man, and t) him the chief feature was " the predominance
of a well-defined luminous bar extending acro.'S the heavens
directly overhead from one horizon to the other — from magnetic
east to west.

"The stars shone through this band of pale light with
scarcely diminished brightness, but it was occasionally flecked
by thin clouds. When I first saw it, at 9 20 p.m., there seemed
to be traces of oblique striation crossing it, and Dr. Tellet,
who called my attention to the display, slates that ten minutes
earlier, when the bar was at its brightest, these strialions gave
the effect of slightly twisted folds. Another informant remarked
that the bar was formed shortly before 9 p.m. by the union over-
head of rays which shot upwards for the east and west.

" The light waned rather rapidly with ?light pulsations, and
we thought that we could detect a slow southerly drift in the
band before it vanished. The western portion died out before
the eastern, which remained quite detinite until 9"45 p.m.
Meanwhile there had been a faintly diffused illumination of
the northern heavens, with occasional suggestions of radiant
streamers, but the whole quite subordinate in brightness to the
band overhead.

" There was a westerly breeze and a nearly clear sky, with a
low cloud-bink in the north-west, at the commencement of the
display, but before 9'45 p.m. the wind had backed southward,
and shortly afterwards the sky became suddenly overcast, though
not before the aurora had faded to a scarcely perceptible glow.
Half an hour later a slight shower fell."

The Rev. S. Barber says that the aurora was visible at Wesl-
newtOD, Aspatria, in great brilliancy, as a band passing nearly
over the zenith from the west to the east horizon at about
10 p.m. .\n arch of light was seen in the north from about
8.30, and some observers saw a shorter band almost north and
south preceding the great band west and east.

Mr. J. Cuthbertson saw the display at Kilmarnock, N.B., as
early as 7.45, "as a broad arch of light crossing the heavens
from east to west. .Vbaut 7.50 it was a very luminous pencil
of light in the upper part of the heavens, through which
stars of the second and third magnitude were distinctly visible,
As it condensed it grew brighter. .About ten minutes after I
first observed it, it began to fade, and was invisible before 8
o'clock, leaving a temporary brightness in the western sky."

The aurora appears to have presented features very similar to
those of the aurora of November 23, 1894, observations of
which were discussed by Prof. A. S. Hetschel in Natitre of
January 10.

THE U.S. UNITS OF ELECTRICAL MEASURE.
"D Y a law approved in the Senate of the United States, last
July> '' *"5 enacted that the legal units of electrical
measure in the United States should be as follows : —

(1) The unit of resistance shall be what is known as the
international ohm, which is substantially equal to one thousand
million units of resistance of the centimelre-gramsecond system
of clectrcmagnelic units, and is represented by the resistance
offered to an unvarying electric current by a column ai mercury
at the temperature of melting ice fourteen and four thousand
five hundred and twenlyone ten-thousandths grams in mass,
of a constant cross^-ectional area, and of the length of one
hundred and six and three-tenths centimetres.

(2) The unit of current shall be what is known as the inter-
national ampere, which is one-tenth of the unit of current of
the ccntimetre-Kramsccond .'•ystem of electromagnetic units,
and is the practical equivalent of the unvarying current, which,
when passed through a solution nf nitrate of silver in water in
accordance with standard specifications, deposits silver at the
rate of one thousand one hundred and eighteen millionths of a
gram per second.

(3) The unit of electromotive force shall be what is known
as me international volt, which is the electromotive fjrce that,
steadily applied to a conductor whose resistance is one inter-
national ohm, will produce a current of an international ampere,
and is practicilly equivalent to one thousand fourteen hundred
and thirty- fourths ol the electromotive force between the poles
or electrodes of the voltaic cell known as Clark's cell, at a
temperature of fifteen degrees Centigrade, and prepared in the
manner described in the standard specifications.

NO. 1326, VOL, 51]

(4) The unit of quantity shall be what is known as the inter-
national coulomb, which is the quantity of electricity transferred
by a current of one inlcrnational ampere in one second.

(5) The unit of capacity shall be what is known as the inter-
national farad, which is the capacity of a condenser charged
to a potential of one international volt by one international
coulomb of electricity.

(6) The unit of work shall be the Joule, which is equal to ten
million units of work in the centimetre-gram-second system,
and which is practically equivalent to the energy expended in
one second by an international ampere in an international ohm.

(7) The unit of power shall be the watt, which is equal to
ten million units of power in the centimetregram-second system,
and which is practically equivalent to the work done at the rate
of one Joule per second.

(8) The unit of induction shall be the Henry, which is the
induction in a circuit when ihe eleclromo'.ive force induced in
this circuit is one international volt while the inducing current
varies at the rate of one ampere per seconi.

The National Academy of Sciences was instructed to prescribe
and publish the specifications necessary for the practical appli-
cation of the definitions of the ampere and volt given in the fore-
going,iand, to meet this requirement of Congress, a special com-
mittee was appointed to consider the subject. The committee,
selected from members of the .\cademy, w.as as follows : — Prof.
H. .\. Rowland, chairman. General II. L. Abbot, Prof. G. F.
Barker, Prof. C. S. Hastings, Prof. A. A. Michelson, Prof. J.
Trowbridge, Dr. Carl Barus.

The report of this committee was submitted to the Academy
at a special meeting held last month, and was then accepted and
unanimously adopted. We extract the following details from the
report, a copy of which has just reached us.

The Am pen.

In employing the silver voltameter to measure currents of
about one ampere, the following arrangements shall be
adopted : -

The kathode on which Ihe silver is to be deposited shall take
the form of a platinum bowl not less than 10 centimetres in
diameter, and from 4 to 5 cenliniLlrcs in depth.

The anode shall be a disc or plate of pure silver some 30
square centimetres in area and 2 or 3 millimetres in thickness.

This shall be supported horizontally in the liquid near the top
of the solution by a silver rod riveted through its centre. To
prevent the disintegrated silver which is formed on the anode
Irom falling upon the kathode, the anode shall be wrapped
around with pure filter paper, secured at the back by suitable
folding.

The liquid shall consist of a neutral solution of pure silver
nitrate, containing about 15 parts by weight of the nitrate to
85 parts of water.

The resistance of the voltameter changes somewhat as the
current passes. To prevent these changes having too great an
effect on the current, some resistance besides that of the volta-
meter should be inserted .in the circuit. The total metallic
resistance of the circuit should not he less than 10 ohms.

Method of iiutkiiig a Memurcmcnt. The platinum bowl is to
be washed consecutively with nitric acid, distilled water, and
absolute alcohol ; it is then^to be dried at 160 C, and left to
cool in a desiccator. When thoroughly cool it is to be weighed
carefully.

It.is to be nearly filled with the solution and connected to the
rest of the circuit l)y being placed on a clean insulated copper
support to which a binding screw is attached.

The anode is then to be immerse<l in the solution so as to be
well covered by it and supported in that position ; the connec-
tions to the rest of the circuit are then to be made.

Contact is to be made at the key, noting the lime. The
current is to be allowed to pass for not less than half an hour,
and the lime of breaking contact observed.

The solution is now to be removed from the bowl, and the
deposit washed with distilled water, and left to soak fir at least
six hours. It is then to be rinsed successively wiih distilled
water and absolute alcohol, and dried in a hot air bath atatem-
pcral«re of about 1 60° C. Alter cooling in a desiccator it is to be
weighed again. The gain in mass gives the silver deposited.

To find the time aver.ige of the current in amperes, this mass,
expressed in grams, must be divided by the number of seconds
during which Ihe current has passed, and by 0001 1 iS.

In <lelermining the constant of an instrument by this method.

March 28, 1895]

NATURE

519

the current should be kept as nearly uniform as possible, and
the readings of the instrument observed at frequent intervals of
time. These observations give a curve from which the reading
corresponding to the mean current (time-average of the current)
can be found. The current, as calculated from the voltameter
results, corresponds to this reading.

The current used in this experiment must be obtained from a
battery, and not from a dynamo, especially when the instrument
to be calibrated is an electrodynamometer.

The Volt.

Definition and Properties of the Cell. — The cell has for its
positive electrode, mercury, and for its negative electrode,
amalgamated zinc ; the electrolyte consists of a saturated solu-
tion of zinc sulphate and mercurous sulphate. The electro-
motive force is I '434 volts at 15' C, and between io° C. and
25'C.,by the increase of l' C. in temperature, the electro-
motive force decreases by o'ooil5 of a volt.

To set up the Cell. — The containing glass vessel, represented
in the accompanying figure, shall consist of two limbs closed at

bottom and joined above to a common neck fitted with a ground-
glass stopper. The diameter of the limbs should be at least
2 centimetres, and their length at least 3 centimetres. The
neck should be not less than I '5 centimetres in diameter. At
the bottom of each limb a platinum wire of about 0*4 millimetre
diameter is sealed through the glass.

To set up the cell, place in one limb pure mercury, and in the
other hot liquid amalgam, containing 90 parts mercury and 10
parts zinc. The platinum wires at the bottom must be com-
pletely covered by the mercury and the amalgam respectively.
On the mercury, place a layer one centimetre thick of the zinc
and mercurous sulphate paste described in 5. Both this paste
and the zinc amalgam must then be covered with a layer of the
neutral zinc sulphate crystals one centimetre thick. The whole
vessel must then be filled with the saturated zinc sulphate
solution, and the stopper inserted so that it shall just touch it,
leaving, however, a small bubble to guard against breakage
when the temperature rises.

liefore finally insetting the glass stopper, it is to be brushed
round its upper edge with a strong alcoholic solution of shellac,
and jtres'^ed firmly in place.

T^

on the nature of muscular
contraction:-

'HE subject of this lecture is an inquiry into '" The Nature of
Muscular Contraction." Like all vital phenomena, mus-
cular contraction is a most complicated process, composed of
mechanical, chemical, thermal, and electrical changes in living
matter. Hence it will be our task to become acquainted with

1 The Croonian Lecture, delivered by Prof. Th. \V. Engelinaan,*at the
Royal Society, on March 14.

NO. 1326, VOL. 51]

these changes as completely and exactly as possible, and to
ascerlain their causal connection. Our inquiry must not be
restricted to one special kind of muscle : it will have to extend
to all the different forms, for there can be no doubt but that in
ail these cases the principle of activity is the same. Nay, it
will be necessary to deal even with the other phenomena of so-
called contractility, such as protoplasmic and ciliary motion, for
all these different types of organic movement, however much
they may differ from each other in details, are yet so con-
nected by gradual transitions, that, to all appearance, one
principle of motion, essentially the same, is applicable to all of
them.

The general mechanical principle on which muscular con-
traction is based, will be discovered when we shall have
ascertained in what way the power of shortening proceeds
from the potential chemical energy which disappears upon
stimulation of the muscle.

There can be no doubt as to the fact that the potential chemical
energy of the component parts of muscular substance is alone the
ultimate source of this power, for the existence of any other source
cannot be proved. The quantity of energy which is imparted
to the muscle by the stimulus is too small to be taken into con-
sideration. The early opinion that the power required for con-
traction was imparted to the muscle through the medium of
motor nerves has been refuted by experiments, such as, e.g., on
the persistence of contractility after degeneration of the motor
nerves, and on the effects of direct artificial stimulation of the
muscles ; and it had even been refuted long ere the law of con-
servation of energy had thrown its light on the mutual connec-
tion between the phenomena of the living organs.

This law teaches that all the actual energy which appears in
the muscle in consequence of stimulation must originate in an
equivalent quantity of some other form of energy.

Now this form of energy is, in fact, given in the muscular
substance liable to physiological combustion. The quantity of
the latter is not only theoretically sufficient to produce that
actual energy, but it has even been proved experimentally that
during contraction that material gives birth to combinations
such as carbonic acid, in the development of which potential
chemical energy must have passed into other forms of energy.
As far as the phenomena have been examined quantitatively,
they confirm the conclusion that all muscular force must be
derived from chemical energy.

Hence there is no difference about all these points. But with
this result we have as yet gained only a basis for the proper
solution. So soon you inquire in what way, by what trans-
formations, does the mechanical force of contraction arise from
chemical energy, difficulties and differences of opinion begin to
present themselves.

A great many physiologists hold, with Pfliiger, Fick, and Chau-
veau, that muscular force is a direct manifestation of chemical
attraction; others, <•,.;'., Solvay, think that it is produced
through the medium of electricity ; others again, following J.
R. Mayer, believe that the muscle is a thermodynamic machine,
not unlike our caloric or steam engines.

The Chemiodynamic Hypothesis. — The first hypothesis, ac-
cording to which contraction of muscle is a direct manifestation
of chemical attraction -we may call it the chemiodynamic hy-
pothesis— has to assume ihat the molecules, on the chemical
combination of which this contraction is based, are regularly
arranged within the contractile substance in such a way as to
make them approach each other at their combination in the
direction of the axis of the muscular fibres.

I think that this hypothesis of the identity of chemical at-
traction and muscular force meets with a fundamental difficulty
in the fact that, in a single contraction, only a relatively
infinitesimal part of the muscular substance is chemically
active ; 70 to So per cent, of the muscle (.and even more) con-
sists of absorbed water, the rest contains substances (albumin,
salts, &c.) which, for the greater part, so far as can be proved,
are not chemically concerned in the contraction.

This quantitative composition and this minvte consumption
of the active muscle compel us to assume that relatively only
very few molecules of the muscular substance can be considered
as sources of energy, and of these .again it is generally but a
small part that at a cenain moaient perform their function.

With certain presuppositions we may calculate the quantity
of matter through the chemical action of which the amount of
actual energy, produced at a certain conti action, must have been
generated.

520

NATURE

[March 28, 1895

If we pre»ent a muscle from doing external work during the
contraction, the whole actual energy will present itself in the
shape of heat. When there is but a slight contraction, the
muscle of a frog, e.g., will grow warmer by about oooi" C.
Supposing the specific heat of the muscle to be equal to that
of water (in fact it is less), we find that for a rise ol 0001° C. in
temperature a ijuantiiy of heat of oooi cal. is required for
each gram of muscle. No matter whether this quantity of
heat results from the combustion of carbohydrates, fats, or albu-
minous matter, it can be but an infinitesimal part of the mus-
cular substance that produced it. If, t.g., as is ordinarily sup-
posed, the combustion of a carbohydrate into COo and H«0
produced that heat, taking the heat of combustion ol one gram
of carbohydrate to be broadly 4000 cal., no more than a four-
thousandth part of a milligram will have been consumed in each
gram of the muscle. Hence only about a four-millionth part of
the muscular substance could have been the source of the actual
energy set free by the stimulus, and at the same time, accord-
ing to the above hypothesis, have been the subject of direct
attraction.

But whatever may be our conception of the size, form,
position, and sphere of action of this four-millionth part in
relation to the other soft, watery mass, only passively moved, I
fail to understand how, through direct chemical allniilion, this
one minute part should bring about the movement of the rest of
the four million parts in such a manner as it does.

The adherents of the chemico-dynaniic hypothesis have not
answered this objection as yet. And since they can give but
an unsatisfactory account or no account at all of many other
fads (I will refer to some of these facts further on), we may be
allowed tu cast about for some other explanation.

The EUetrodynamic Hypothesis. — Since Galvani's discoveries,
the electric phenomena of muscles have frequently been sus-
pected to contain the solution of our problem. And, indeed,
it is not so very difficult to mention a series of facts which seem
to bear out the suggestion that the mechanical work done by
the muscle may be created from chemical energy through the
medium of electric forces.

There is, in the first place, the fact that muscles, when in
action, produce regular electiic effects. These effects are in-
deed the first phenomena we can observe after stimulation.
They seem to begin at the very moment of stimulation, shortly
before the contraction, hence they might in so far be the cause
of the mechanical process.

Moreover, as du Bois-Reymond proved, the value of the
electromotor force is very high, and in the active particles is
probably much higher than the force of the currents we can
derive from the surface of the muscle.

.\dd to this that the economic corfficienl of the muscle may
attain, just as in the case of electric motors, a considerable pro-
poition. .As much as 25 per cent, and more of the potential
enetcy which has been consumed may be transformed into
mechanical \\ ork.

Howtver, there are weighty objections to this hypothesis
also. In the first place, there is the fact that these very same
electromotor forces, of cjual intensity and direction, appear,
under the same influences, not only in the muscles, but al-o in
nerves, glands, and other organs, which do not pos.sess the least
contractility. Then there is the important discovery of
Biedermann, that the contractility of muscles maybe completely
neutralised by water or etheric vapours, without doing any
perceptible harm to the electromotor phenomena.

In the same way the development of (he electric organs sup-
plies us with important proofs of the independence of the
eteciiic and the mechanical processes. In most cases these
organs are developed out of striped muscular fibres. Now, in
this process of development, contractility is gradually lost,
whereas the power of producing electrical effects attains a yet
higher degree ol perfection.

The Thermodynamic Hypotlusi.. — More probable than the
chemical and the electrical hypothesis may be deemed a sug-
gestion, first put forward by Jul. Rob. Mayer, though in an un-
tenable form, according to which the muscle is a thermodynamic
machine. I'hysiologiss, however, generally object that this
view is not compatible with the second law of thermodynamics,
for we cannot expect differences in temperature in the muscle
•o great as this law requires they should l>e.

Now I venture to thmk that, on the contrary, we mu^>l ssume
exceedingly great differences of temperature in the stimulated
muscle. What holds good of the whole body holds good of the

NO. 1326. VOL. 51]

muscle also ; the tenipei.iture, treasured with our instruments,
is but an arithmetical aveiage, " comprising an infinite number
of different temperatures, pertaining to an infinite number of
different points" (rfliiger).

From the fact that at the contraction an infinitesimal part
only of the muscular mass is chemically active, we infer that
the temperature of these particles must, at the moment of com-
bustion, be an uncommonly high one. Great as the specific
heat of muscular substance is, it would otherwise be impossibls
to account lor a rise in the temperature of the whole mass even
of o"ooi° C. only.

Since each thermogenic particle is surrounded by a relatively
enormous cool mass, conducting heat and diathermanous, the
principal condition for the transformation of heat into
mechanical work has been satisfied, and, on .iccount of the
enormous diflerences in temperature which we h-tve to assume,
satisfied to such a high degree, that even an economic co-
efficient of 30 percent., nay, 50 per cent., and even more, seems
to be theoretically possible.

Supposing we have to deal with a Carnol's cvcle, the theo-

T - T„
retical maximum Q„ of the mechanical effect is Q,, = Q ^^ - — >

'1
where Q stands for the whole quantity of heat, which from the
absolute temperature T, is sinking down as far as T„. Taking
T„ = 273 -r 37 = 310 , the mechanical cfl'cct might at Tj =
410" amount to 30 per cent., when the temper.iture of the
active particles would consequently exceed the average
temperature of the normal muscle by 100° C. only.

The objection that these high temperatures must necessarily
destroy the life of the muscle, since the latter becomes rigid
and dies even at 50 C, is, for the same reasons, of small im-
portance only. For it is ever but an infinitesimal part of the
muscular mass that is exposed to these high temperatures. At
a small distance from these furnaces ol heat the temperature
must have fallen so low as to be haimless. The muscle will
no more be destroyed by stimulation than a steamer will be
de.'^troyed by heating the furnaces.

However likely it may thus seem that nature should avail
herself of these favourable terms on which mechanical work
may result from muscular heat, we have up to the present time
no direct proof that this is actually the case, nor do we know
in what way it takes place, if in any. But I venture to think
that the proof can now be given, inasmuch Jis it is possible to
demonstrate how, through the medium of peculiar arrangements
of the material of the muscle, a transformation of chemical
energy into mechanical work by means cf heat not only can,
but actually must, be brought about.'

Muicular Structure in relation to Contractility.

7 he Fibrils are the Scat cf the Shortening Power.— Vox this
we need firstly to pay attention to the peculiarities of the micro-
scopical structure of muscle. All muscular fibres of all animals
are composed chiefly cf two parts : extremely thin, lonf;,
albuminous fibrils, and an interfibrillar plasmatic substance,
the so-called .'■arcoplasma. The quantitative relations of both
vary, but the fibrils always occur rn great number, forming very
often the greatest part of the whole mass of the muscle. They
always run parallel to each other throughout the length of the
fibres.

This fibrillar structure is also presented by all the other formed
contractile substances.

Direct microscopical observation during life teaches us that
the fibrils, and not the saicoplasm, are the seat of the shorten-
ing power. The fibrils in a state of relaxation are long and
thin, and often run in winding curves, but grow short, thick,
and straight, in consequence of stimulation. The sarcoplasm
passively follows their movements. Moreover, completely
isolated fibrils can shorten.

Jhe Tilirils arc Contractile lecause they contain Doubly
A'c/ractiTe /'articles.— Thvs the question arises : Can there l)e
demonstrated in the fibrils such arrangements of their material
as by their mediation contractile loicc may originate in a
thermodynamic way ?

Light— /«.!■ optimum -eagens, as Buys Ballot said— solves this

' The tuipirical found.ilions of ihe views Jcvc'opcd in ihis lecture will
be fuiind in "VcMUchc iilxr Aftiderunscn dcr Fotm und derelaslischen
Ki.ifle doiipeIbrcct)cndcr Gewtliiclenicnlc untcr ct.cnii*chcn und lliernii-
»chen tindu^fccn," in the Arpcridix of my Memoir. " Ucbcr den Ursprunft
der M\iflielkrnfl "(ale Auflagc. Lcip/ig. lE<)3. S. 5<eo), and in tlic
iiler.iliirc ritcd in ihc same paper.

March 28, 1895J

NA TURE

=^21

question for us. If we examine the optic properties of con-
tractile fibrils, with the aid of the polarising microscope, we
find that all of them are double-refractive, with one optical
axis parallel to the direction of contraction.

This general occurrence of double-refracting power is the
more indicative of relations lo contractility, since non-contrac-
tile cells, as a rule, lack double refraction, even where we meet
with a fibrillar structure, as in the axis-cylinder of a nerve-
fibre.

Our conjecture gains, I believe, a very high degree of prob-
ability by the following series of observations.

In the first place, the fact that contractility and double
refraction in the course of ontogenesis always appear at the
same time, e.g. in the heart of the chick, on the second day of
incubation ; in the muscles of the trunk and skin on the fifth or
sixth day ; in the muscles of the taiU of tadpoles when the
length of their body is 3 to 4 mm. ; in the muscles of the stalk
of Vorticella, and in cilia so soon as these organs become
visible.

-Vnother evidence seems to me to be afforded by the be-
haviour of the striated muscles. Here the fibrils consist of the
doubly-refiactive sarcous elements and the singly-refractive
material which joins these, the two alternating regularly. The
two are wholly diJTerent as regards their optical, mechanical,
and chemical properties ; and these properties, moreover,
during contraction, change in an opposite way. Hence the
functions of the two must be of a different kind. And since
the changes of form, volume, &c., of the doubly-refractive
parts during contraction prove that in each case there parts
must be the seat of contractile power, the single-refractive
junctions will most probably have another function. We will
come back to these changes further on.

A third evidence is alTorded by the observation that the
specific force of contraction in different muscles is, in general,
greater, the better developed the power of double refraction,
comparison, of course, in each respect being made with parts of
the same thickness.

In the development of the pseudo-electric organs of Kajii
')Ut of striated muscular fibres, one of the signs of the in-
cipient change of structure and function is the vanishing of
double refraction in the sarcous elements. In an early stage
of development this vanishing is, with Raja clavata, the very
lirst and the only sign that the fibre is about to be transformed
trom a contractile into an electric organ.

But particularly significant seems to me to be the behaviour
of the obliquely striated muscles of Molluscs and other Inveite-
brata. Here the doubly refractive fibrils do not run parallel
to the axis of the fibre, but describe spiral lines round it :
and during a contraction the steepness of the curves decreases,
■io that the angle formed by the longitudinal axis of the fibril
and the longitudinal axis of the fibre may increase from 5' in
ho relaxed state to 60', and even more, in a state of powerful
contraction. But the optic axis of the fibril, instead of assum-
mg, in this case, a more oblique position also, as might be ex-
pected on morphological ground'-, remains parallel to the longi-
tudinal axis of the fibre, and consequently to the direction of
shortening of the fibre. Hence it is not the morphological axis
of the fibrils, but the optical axis of their doubly refractive
constituents, which coincides with the direction of the contract-
ing force.

CoHtraclilily a General Property of Doubly Refractive
Bodies. — More than a score of years ago I pointed out the fact
that even non-muscular elements, elements not possessing
irritability in the physiological sense of the word, nay, even
lifeless, unorganised elements which are uniaxial doubly
refractive, may, under certain influences, contract in the
direction of the optical axis, all thickening at one time, ard
contracting with a force and quickness and to an extent
rivalling that of muscles, if not surpassing it. Instances
of this are the fibrils of the connective tissue, of the tendons,
and of the cornea, and otheis. The same contractile power
was found by von ICbner in a great many other doubly-refractive
histological elements, nay, even in substances capable of
absorption and thereby made doubly refractive, ,-. j-., dried col-
loid membranes ; and finally by Hermann, in fibrils of fibrin.

I have in this «ay shown that singly refractive, or only
feebly doubly refractive histological elements, such as the fibies
of elastic tissue, obtain, in the same w.ay as caoutchouc, the
power, when made doubly refractive by extension, of contract-
ing under certain influences, and further that the force of

shortening will generally be greater in proportion to the
amount of the double refraction thus artificially produced.

Since, according to Mitscherlich's discovery, similar changes
of form may be observed in doubly refractive crystals, we have
apparently to deal with a property pertaining to all doubly
refractive bodies as such.

Heat as a General Cause of Contraction of Doubly Refractive
Elements. — Now, the influence which in all these cases is able to
evoke the mechanical energy of shortening is elevation of tem-
perature. Refrigeration has the opposite effect.

Particularly instructive is the thermal contraction of the
fibrillar connective tissue, on account of its similarity to
muscular movement, even with regard to details.

In tendons .and many membranes the fibrils, as well as
those of most muscles, are arranged into bundles, all, or nearly
all, parallel lo each other. For this re.ason such objects are
extremely well fitted for a closer examination of the phenomena
of movement. The most suitable material I know is furnished
by the catgut strings of violins, which chiefly consist of such
bundles, running in steep spiral lines, round the longitudinal
axis of the string. They are distinguished from the
greater number of naturally occurring objects by their very
regular cylindrical shape and their elasticity. < 'n these
properties is based their suitability for musical purposes,
especially for the so-called "perfect fifth" (" Quintenrein-
heit").

The Muscle- I^PoJel. — With the aid of such a string we can
compo-e a model which in a simple way explains how in the
muscle mechanical energy of contraction may result from heat
without any perceptible rise of the average temperature of the
muscle.

A piece of an E string of a violin, about 5 cm. long and
previously swollen in water, is fastened to the end of the short

IT

i ^^

^

NO.

1326, VOL. 51]

Fig. I.

rigid arm of a steel rod, while the upper end of the string is
fixed to the shorter arm of a lever, turning round an horizontal
axis.

To this string different tensions may be imparted by weights
or springs, acting upon the lever.

Round the string, but without touching it, runs for
a length of about 20 mm., and in about twenty curves,
a spiral of thin platinum wire. The ends of this may be
connected with the two poles of a Grove or lUinsen
battery of three or moic cells. The rod, bearing the lever
string and spiral wire, is placed in a glass of about 50 c.c.
contents, filled with water of about S5-'6o' C, and closed at
the top by an ebonite lid. Through an aperture in the lid, a

522

NATURE

[March 28. 1895

thermometer is placed in the water in such a position that it
will remain at a distance of about I cm. iiom the spiral wire.

The string is now obseived fcr some minutes at a tension of
25 or 50 grammes and at a constant temperature until no
further change in the position of the lever can be discerned.
If we now close for some seconds Ihe circuit of the battery
through Ihe spiral, the lever rises. Ufoti opining the circuit, it
falls. The thermometer in the ^lass indicates a hardly fercepttble
rise in temperature, or no rise at all.

■\Ve see the doubly-refractive string of our model corresponds
to the doubly-refractive muscular particle, which we suppose
to be the seat of the force of contraction, and therefore may be
called " inotasma" ; the water in the glass represents the
watery isotropic substance round the inolagma, doing duty as
refrigerant ; the spiral wire supplies the place of the chemically
active t/:ermogenii- molecules ; the closure of the galvanic cir-
cuit corresponds with the process of the stimulation of the
muscular element.

The movements may be inscribed on a rotating cylinder.
We then obtain curves of the same character as contraction-
cur\-5 of muscles.

Fic. 3.

Such a (T^on/o^jraOT presents, like a myogram, three periods,
viz. : —

(1) A period of latent energy, the duration of which, just as
with the muscle, decreases with the increasing energy of the
stimulus (;.<'., with the intensity -and duration of Ihe electric
current), with rising temperature and with decreasing load.

(2) A peiiod of augmenting energy, in which contraction
lakes place with a rapidity, first increasing, afterwards diminish-
ing, the contraction being, within certain limits, more rapid
and the larger in extent the stronger the stimulalion.

(3, A period of declining eneigy, in which the string relaxes
with a gradually decreasing rapidity.

further Coiiiparalive Researches on the Thermal Contraction
of Lijeiess Double Kefractivc Bodies and the Physiological Con-
traction of Muscle. — The points of resemblance between our
model and a muscle extenil much further yet, and amongst
other points to peculiarities which seem to bear important testi-
mony to the identity of the mechanical process in the two cases.

Such a resemblance I find, in the first place, in the fact that
the strength of the shorteuitii; fcucr, dix eloped ly a certain
stimulus, increases with the /f a. /within certain limits. Holh
muscle and string present the paiadoxical phenomenon that,
under a stimulus of equal energy, heavier weights may be lifted
higher than lighter ones.

Neither the chemical nor the electrical hypothesis of the
origin of muscular force can give a suflicienl explanation of this
fact. On the basis of our theory, on the contrary, it can be
predicted, because cveiy influence which aufmenis the doubly-
refractive ix)wer must laise the power of contraction.

Now, von Kbner has j^roved experimentally that Ihe force of
double refraction of tcndor.s and also, between certain limits, of
muscles, increaics willi the load. The same is the cise with
fibres of elastic tissue an<l with caoutchouc, and with these also
the contractile power incrca.'es with the load. The differences
of force thus depending on the load are by no means insignifi-
cant.

Connected with this point is another fact, viz. that the force
of shortening produced in our model by means of a given rise
of temperature, il Ihe smaller Ihe more the string has already
contracted. The maximum of force is, at all events, displayed
when the extension of the siring is brought by the whole load
)>cing applied at once at the very beginning of the healing, not
after the string has already contiaclcd \>itli a smaller load.

The very same thing, as Schwann's experiments showed
many yeais ago, holds good of muscle. On the hypothesis of
chemical attraction we should decidedly expect the reverse:
viz. increase of force with an increasing mutual approach of
the combining molecules ; so also in the same way on every
other hypothesis which pronounces contraction to be caused by
atlra ctive powers increasing in inverse proportion to the square
of distance.

In the fact discovered by Schwann, Johannes Miiller thought
he had found a refutation of the old electro-dynamic hypothesis
of Trevost and Dumas, as well as a valid reason for assuming a
fundamental rel.ition between the vit.il power of contraction and
physical elasticity.

Ilowevcr, as Hermann has observed, we might in this case
get over the difficulty by supposing that between or in the length
of the parts attracting e.ich other, there are elastic layers oppos-
ing that altiaction with incre.ising force. It is evident that our
view of the matter does not require such an auxiliary hypothesis,
because, in accordance with Eduard Weber, we regard muscular
contraction as only a special case of elastic shortening.

A closer experimental comparison of the dianges undergone,
on the one hand, by the ekisticity of our string during thermal
shortening, and, on the other h.ind, by muscular elasticity during
jihysiological contraction, will teach us that, in each case, the
changes are of exactly the same kind.

.-Vs regards striated muscles, it was Eduard Webev who, by
his classic researches, established that their extensibility in-
creases during contraction. The same is now proved to hold
good of strings and other organic doubly-refractive substances
during thermal shortening.

The curve of lengthening of all these objects inclines more
sharply towards the ,-ibscissK of the loads the higher the tempera-
ture. Both curves converge, and may finally even cross, i.e. a
certain load being exceeded we do not get contraction but
lengthening as the efTect of heating.

This circumstance explains the fact, sometimes observed by
E. Weber, that living, tired, heavily-loaded muscles of frogs,
lengthen instead of shorten as a result of electric stimulalion.
Considered from other theoretical points of view, this obser-
vation seems so paradoxical that its very validity has been
(luestioned by some ]>hysiolrgists, but in the face of the direct
and exact measurements of so scrupulous an observer and
inquirer as Eduard Weber, we have no right to do this.
According to our view of the origin of muscular force this fact
is not paradoxical at all, but might be foreseen.

The decrease of the shortening power and the increase of
extensibility with increasing thermal contraction is, in the case
of our lifeless doulil) -refractive objects, accompanied by a de-
crease in the power of double refraction. According to von
Ebrer's careful nie:isuiemcnls, the same thing is the case with
muscles during vil.il contraction. We may consider this fact,
too, as an important proof of the fundamental resembhince
between the process of contraction in our model and in the
muscle, and at the same lime as a further evidence of the exist-
ence of a causal relation 1 ctween double refraction and con-
tiactility in geneial. lUit it is the physicist's task, and not the
physiologist's, to j enettate funher into the relations between
optic and clastic piopcrties. The physiologist may deem his
purpose attained when be succeeds in tracing a certain vital
phf nomeron back to pioce.sses which may .ilso be observed in
lifeless bodies.

However, though we should, perhaps, be inclined to infer
from Ihe foregoing that we have successfully acquitted ourselves
of this task with regard to muscular contraction, we will be
careful not to overlook the numerous im]K>rtant respects in
which a muscle as a living body, that is, one subjected to
constant chemical transfoimation, differs from our lifeless
strings. The study of these difl'erences is most instructive,
since il throws a new lighl on a series of processes nearly allied
to contraction, especially on the phenomena of rigor mortis Md
tonus of muscle.

Hut before entering into this we shall first have to meet
another important objection to our views. It is based upon the
absolute amount of muscular force. This amount may, as you
krow, be very high. Human muscles at the .strongest tetanic
contiaction can shorten with a force of about lo kilogrammes to
I sq. cm. transverse section. Now such a force must, according
lo our view, be produced by a small part only of the transverse
see'ion of the muscle.

With a maximal tetanus, it is tiuc, the Icnipcraluic of the

NO. 1326, VOL. 51]

March 28, 1895]

NATURE

523

whole muscle does rise l° C. or more. Hence there are,
perhaps, looo times more particles chemically active than with
a moderate simple contraction, where the temperature rises
O'OOl" C. only. Consequently, during such a tetanus, a much
greater part of the muscular substance — perhaps loao times as
much — will be healed to such a degree as is required for an
obvious contraction of the inotagmata. But even in this case
the greater pait of the whole substance will be only moved
passively.

Can such very important mechanical powers as we are
obliged to assume in the inotagmata be evolved through the
thermical contraction of doubly-refractive boJies? Do we not,
as Fick says, in making such a supposition, go too far beyond
the bounds of legitimate analogy ?

Of course nothing but the measurement of the force; de-
veloped by lifeless doubly-refraclive bodies under thermal con-
traction will decide this question. I have made many of these
measurements on variojs objects, and I think the results afTord
us a refutation of the objection. Strings, moist but not yet
contracted through lying in water, with a diameter of 07 mm.,
and loaded with i kilogramme, lif ed up the weight in a per-
ceptible degree when rapidly healed up to 130' C; that is to
say, they exei ted a force about twenty times at least as great
as the maximum force of a human muscle of the same thickness.
Still greater forces may be exerted by strips of cajutchouc
rendered in a high degree doubly refractive by strong extension.
Even by merely heating from 10' to 40" C. powers could be
produced sixty times as great as the maximum afTorJed by
human muscles of the same transverse section.

Hence we may sufficiently account for the greatest display of
force in the muscle, without having to attribute to the inotag-
mata higher elastic forces than we observe in highly extended
threads of caoutchouc of the same thickness, nay, without even
having to assume temperatures reaching the degree necessary
for the coagulation of albumin.

It is a pity that we are not al)le to subject the isolated doubly-
refractive parts of the muscle in an unimpaired condition to the
influence of heat. Together with the elevation of temperature
there occur changes in the chemical processes, an 1 therewith in
the material composition and mechanicil propertie;, of the
whole muscle substance, which complicate the change; de-
pendent only on the heating of the doably-refractive pirticle--,
or even prevent our clearly recognising I hem.

Tclanus and Kigor by Heat. — Livmg muscles, when being
^raJnal/y heated, will, as you know, contract tetanicilly sj
soon as the temperature has attained a height which ii but little
below 50' C. This so-called tetanus of heat passes b/ prolonged
heating into the lasting contraction of rigor, in this case
combined with definitive loss of irritability.

This contraction through heat agrees at so many points with
physiological contraction, especially with physiological tetanu;,
that it w.as held to be a Jast manifestation of muscular life.
.Such points of resemblance are, e.g., the amount and the force
of shortening, which in bolh cases are at least of the same
order, and the increased production of heat, carbonic acid, and
a fixed acid.

No doubt in this case a very important and general rise of
temperature of the contractile particles will take place so soon
as rigidity begins to announce itself. Consequently, according
to our hypothesis, we must expect a strong and general
contr.-iction of the inot.tgmata.

That the force, with which the muscle as a whole will
shorten, is not quite so great as with physiological tetanus, is
sufficiently explained by the fact that the inotagmata d) not
contract simultaneously, and by the increase of internal re-
sistance which occurs, due to coagulation and precipitation in
the muscle plasma during the development of rigidity by heit.
The latter circumstance seems to explain, loo, why the rigid
muscle does not perceptibly lengthen, or lengthens very little,
upon cooling.

Turgescence by Absorption as a General Cause of Contraction
<y Doubly. refractive Organised Elements. — On a closer examin-
.ition, however, we find that matters are still more complicated,
and likewise that there is still an important circumstance which,
besides the lise of temperature of inotagmata, may act as a
cause of contraction, even of permanent cjntraclion. This
circumstance, the fundamental importance of which to muscular
contraction was disclosed a score of years agd by a rigorous
microscopical examination of the processes taking place in the

muscle fibres during contraction, is the turgescence of the doubly-
refractive elements by the absorption of watery liquids.

All histological elements possessing doubly-refractive power
tend, even at an ordinary low temperature, to shorten in the
direction of the optical axis when their volume is enlarged by
the absorption of a watery fluid, and to lengthen when their
volume diminishes by loss of liquid. The extent, power, and
rapidily of the changes of form depend on the nature ond on the
dimensions of the turgescent object, and on the nature and
quantity of the absorbed liquid.

For the examination of these relations our violin strings again
yield fit material. A long series of itieasurements has now
shown that there is a vety far-reaching resemblance between con-
traction by turgescence and thermal and physiological con-
traction. I may mention the marked extent of the shortening,
the high value of the force of contraction, its increase with the
initial tension and its decrease with incre.asing shortening, the
increase of extensibility, the decline of refractive power and of
doubly-refractive properly. The resemblance is by no means
exclusively of a qualitative, but also of a quantitative kind.

A change of form generally takes place when the composition
of the absorbed liquid changes, and it is of great impoit.ance to
our question that even the slighte.t changes of composition can
cause marked contraclions and great mechanical effects.

Unloaded E strings, e.g., contract in pure water to nine-
tenths, and in water which contains o 25 per cent, only of lactic
acid to three-fifths of the initial length. At 15' C. they exert,
in the first case, forces of about 80 g., in the second of about
nog. By absorbing a o"25 per cent, solution of lactic acid at
initial tensions of 5, 215, and 425 g. there were exerted powers
of "5> 35O' ^"fl 49° g- respectively, i.e. forces very much
higher than a muscle of the same thickness can produce during
teianus.

Upon nentralisation or dilution the old length and volume
return. The doubly-refractive fibrils, or the sarcous elements
of muscles, contract considerably also under the same
conditions, swelling at the same time ; this is the case even
with muscles which have been killei in alcohol. In such
instances I measured in the striated fibres of insects shortenings
to 50 per cent, and more.

Since, according to many inquirers, lactic acid is formed

during the rigor of striated muscles, and at all events the

reaction of the muscular plasma becomes acid, the dcubly-

I refractive elements must necessarily swell more and tend to

I shorten, and this contraction will remain uaiil the acid has been

' neutralised or removed by diffusion.

Similar results will follow in other cases of rigor characterised
by shortening and by the production of much acid. X.ay, in
the bloodless muscle even a physiological stimulation, when
sufficiently strong an<l long, may be expected to produce a
lasting shortening, on account of the gradual increasing acidity.
Indeed, the well-known incomplete relaxation of such muscles
seems to me to be a symptom of this chemical contraction, as it
may be called, in contrast with the thermal.

In a muscle in which the blood stream is maintained this will
not so easily take place, not even under a strong and prolonged
stimulation, because the acid is immediately neutralised or re-
moved through diffusion. Even in the isolated, bloodless
muscle ihe acid, which is produced by stimulalion, may, in the
beginning at least, be tendered harmless through the very large
quaniity of non-acid fluid absorbed by the muscle. Conse-
quently we must expect in these cases an immediate and com-
plete relaxation after contraction. The facts agree absolutely
with these suppositions.

It is, perhaps, not unnecessary to remark that all these obser-
vations would also hold good if the material affecting the tur-
gescence were not lactic acid, but another substance aiising
during the chemical action in I he mu«cle, e.g. water.

The different parts played by " riurmal " and by ' ' Chemical"
Contraction in the different kinds of Muscular Contraction. —
But now the question may be raised, Is not physiological con-
traction due to turgescence solely ?

\Vc have all the more reason to put this question, since we
can prove that in the physiological contraction of siriated
muscle-fibres the doubly-refractive layers swell at the cost of
the watery isotropic layers. The micioscopic.al examination of
active living musclts and of fixed waves of contraction has
proved this fact beyond all question, however much the opinicns
of different observers may diverge on other points. The swell-

NO. 1326, VOL. 51]

5-4

NATURE

[March 28, 1895

ing woald, moreover, account for the slight decrease of mus-
ctilar volume observed in s ron» tetaaic coatra:tion. For,
according to the experiments of Qaincke, the abiorptim of
water by organised bodies generally leads to a slight condensa-
tion.' By this condensation farther heat is developed, and
this heat might, by raising the temperature of the doubly-re-
fractive elements, be partially transformed into me:hanical
energy, and in this way contribute totheproiuctioa of muscular
force.

\'et I cannot consider this e.vplanation as sufficient for all the
facts. The same argument which in our eyes seems to dispose
of the hypothesis of the identity of chemical attraction and
muscular force, viz. the infiniiesimally small quantity of sub-
stance which is chemically active during a simple contraction,
seems to me to present a fundamental difli-ulty here also. It
is hard to understand how through a change in the material
composition, effected at one infinitesmal point within a soft
watery substance, the whole mass should shorten and thicken,
u)ih:s thtrt procctiis from the centre of chemical activity a coii-
siJerable amount of kinetic energ}' throughout the subitance.

The microscopic appearances which prove the turgescence
of the doubly-refractive elements during a contraction, do
not exclude a direct thermo-dynamical effect. For the
almost complete identity in the changes of form, and of the
optical and mechanical properties which the doubly refrac-
tive constituents of all histological elements undergo during
chemical and thermal contraction, seems to bear out the
hypothesis, that in the thermal shortening of doubly-refractive
elements, through the absorption of watery fluid, we get a
shifting of solid and liquid substances analogous to that of
turgescence. With most of the microscopical appearances,
especially the so called fixed contraction waves, we have, more-
over, to do with a high degree of tetanic contraction, or even
with rigor, in which, on account of the greatly increased
chemical action, a chemically-caused turgescence may have
combined in a considerable degree with the thermal con-
traction.

Hence, we may conclude that chemical contraction by
turgescence of the inotngmala is most likely a constant con-
comitant of the thermal contraction of living mu<cle, but that
compared with the latter, in a single contraction at least of
striated fibres, the former is of little or no consequence as
regards the shortening effect.

Chemiotonus and 'J'hermotonus. — Both'processes will probably
also take part in varying proportion in the ionui of muscle,
which in some cases will approach more to pure chemiotonus,
in others more to pure thcrmotonus.

Causes of the Relaxation of Atusclc. Theoretical Considera-
tions. Conclusion. — With regard to the relaxation of muscle,
according to our theory this must be caused either by cooling,
or by the withdrawal of water from the doubly-refractive
particles. Indeed, we have found that generally doubly-
refractive histological elements, even if they be lifeless like our
violin strings, lengthen again upon cooling after they have been
contracted by heal, and that lliey lengthen upon neutralisation
or diffusion, after they have been contacted by absorption at an
ordinary temperature.

In a normal relaxation the muscle seems to return com-
pletely to its initial state. Of course its store of energy has
diminished in proportion to the quantity of mechanical work
and heat which have ])roceeded from it, but, on account of the
relatively infinitesimal quantity of substance which is thereby
consumed, this return will necessarily seem to be complete even
in the case of the isolated muscle.

When analysing the phenfimena of relaxation more exactly,
we shall light on several possibilities, the discussion of which
Would be very interesting with regard to the theory of
masclc-lire. I shall restrict myself to the phenomena of the
relaxation following on thermal contraction.

Here, in the first place, we might conceive that the doubly,
refractive inot.agmata arc ilcstroye 1 in the thermal shortening,
so that each of lliem performt(.ls fiinclion once only. The
lengilr-ning of the muscular fibrils would then probably be
caused solely by the clastic powers of the parts passively ex-
tended or compressed by the shortening of the inotagmato.
Upon a fresh slimuUlion other inot.n^mnta would, in conie-
quciice of the combustion of other thermogenic molecules, be
active, peri.sh, &c. Through the activity of the formative matter

' In the thermal contraction of tendons and strin2» I have not yet been
able to coavince myself of .-i decrease in volume.

NO. 1326, VOX,. 51]

of the living muscle-fibre, the place of the lost inotagmata would

I be continually or periodically filled by others, probably through
the same process of organic crysiallisation by which during
ontogenesis the doubly-refracting particles in the muscle arepro-

I duced and disposed.

Against this hypothesis, however, or at least again^^t its general
v.alidiiy, various objections m.iybe put forward. I will mention

] two only of the most important of them.

There seems to be no doubt but that the doubly-refractive
particles of the muscle consist of an albuminous substance, and

I that they together make up a sensible part of the whole albumin

' of the muscle fibrils. In that case it would be most improbable
that a great increase of muscular work should not at all, or very

i slightly only, increase the elimination of nitrogen. To account
for this, we should have to recur to an auxiliary hypothesis,
and assume either that the nitrogenous remainder of ihe de-
stroyed inotagma is retained within the body — perhaps in the
muscle — for purposes of anabolism, or, which is most improt ■
able indeed, that other organs saved just as much albumin :.

I was decomposed above the normal quantity duiing the cor.-
traction of the muscles.

A second objection consists in the fact that after heatini;
tetanising muscles until they are rigid, the doubly-refractive
power of the jarcous elements will be found slill very great.

The other possibility is that the imiagmata may be preserved,
and consequently on cooling may return to their former state,
and therefore will do work by shortening as often as we choose.
In this case muscle would not only seem to offer, but would
ofler in fact, a most striking resemblance to a thermodynamic
machine, the solid particles of the framework of which are not
destroyed through the chemical process producing the actual
energy. No more than such a machine would the muscle
require a perpetual renewal of the framework for the con-
tinuation of its activity ; it would only want a periodic supply
of fresh heating material.

This representation, as you see, will sufficienily account for
the fact, which would otherwise remain surprising, that mus-
cular work has such a small influence on the elimination of
nitrogen. The facts of microscopic observation also agree
with it.

Hut a further discussion of the two possibilities would lead us
too far. The purpose of this lecture was not to record a complete
inquiry into all the phenomena of muscular activity. I have
wished chiefly to draw attention to a series of facts which I hoKl
to be of great importance for a deeper insight into the essence ol
muscular contractility, in so far as they prove the existence it
certain material dispositions and processes (admitting of closti
experimental examination}, by means of which mechanical work
may be generated in the muscle by chemical energy.

THE SNAIL FAUNA OF THE GREATER
ANTILLES.
T^IIE West Indian Archipelago has long been known to pre-
■*■ sent some interesting problems in the distribution of its land
fauna. These peculiarities, it will be remembered, led Wallace
to infer the previous existence of a land connection of the
greater islands with one another and with the mainUand ; while
otiiers have claimed that the islands have always been distinct,
and have been colonised by the agency of currents, winds, and
other indirect means of dispersni. An interesting contribution
on this subject has recently appeared in the form of a study of
the distribution of the West Indian land and fresh-water
molluscs, by Mr. C. T. Simpson, of the U.S. National
Museum, from whose paper we extract Ihe following con-
clusions. A considerable portion of the land snail r.auna of tli
(jreatcr .'\ntilles >cems to b; ancient and indigenous. Then
I appears to be good evidence of a general elevation of the

Ijrcatcr AntilKan region, probably some lime during the |
I Kocene, afier most of the important groups uf snails had come
I into existence. .\t this time the larger islands were united,
and were connected with Central America by way of Jarnaic
and possibly across the ^ ucalan Channel. There was then
considerable exchange of species between the two regions. A
some time during this elevaiion there was probably a landway
from Cuba across the llahaina plateau to the Floridcan .area,
over which ccitain groups of Antillean land molluscs crossed.
The nioie northern isles of the I.esscr Antilles, if then elevated,
have I'lobably been since submerged. Alter the period ol

March 28, 1895J

NA TURE

525

elevation there followed one of general subsidence, and first
Jamaica, then Cuba, and afterwards Haiti and Puerto Kico
were separated. The connection between the Antilles and the
mainland was broken, and the Bahama region, if it had been
previously elevated above the sea, was submerged, the sub-
sidence continuing until only the summits of the mountains of
the four Greater Antillean islands remained above the water.
Then followed another period of elevation, which has lasted no
doubt until the present time, and the large areas of lime-
stone uncovered (of Miocene, Pliocene, and post Pliocene age)
in the Greater Antilles have furnished an admirable field lor
the development of the groups of land snails that survived on
the summits of the islands. The Bahamas and the Lesser
Antilles were subsequently raised above the surface, and have
been colonised by forms chiefly drifted in the former case from
Cuba and Haiti, and in the latter case from South America,
while a few stragglers have been carried by sea no duubt from
the Greater Antilles, and have settled on the more northern of
the Windward Islands.

UNIVERSITY AND EDUCATIONAL
INTELLIGENCE.

A DEPUT.\TI0N from the Association of Head Masters of
Higher-Grade and Orjjanised Science Schools was received on
Thursday last, by Mr. Acland, at the offices of the Scien> e and Art
Department; MajorGeneral Sir John Donntlly being present
at the interview. The deputation was the outcome of a very
large and representative meeting of the association, held at
Derby, to consider the new rules for organised science schools
lately issued by the Department. The impoitance of the new
regulations lies in the (act that under them a system of secondary
schools will be inaugtiraled and carried on under the control
of, and supported to a great extent by, the Science and Art
Department. The organi-ed science schools at present in
existence include nearly all the more important higher-grade
schools, the day schools of technical institutions, and a con-
siderable number of grammar schools. The principal changes
proposed in the new rules are the parfal substitution °of
inspection for examination, the introduction of special courses
of instruction for women students, the inclusion of a fair
proportion of lierary work in the curriculum, and the addition
to it of practical work in physics and biology. A long dis.
cussion, lasting over two hours, took place, at the end of which
Mr. Acland stated that he hoped to be able to meet the wishes
of the deputation with regard to many of the points raised, and
promised, at the end of a week or ten days, to make a definite
statement of the alterations the Depaitment would be prepared
to make.

Geometrical Drawing has hitherto been included in Science
Subject I. (Practical, Plane, and Solid Geomeirv ) of the Science
and Art Department. It has just leen decided, however, to
make Geomettiial Drawing a separate subject under the A^t
portion of the Department's Diiecioiy ; so the syllabus of the
Elementary Stage of Scif nee Subject I. will in future include
only plane geometry, solid geometry, and graphic arithmetic.
The changes will come into lorce for the session 1S95-96.

The Senate of Glasgow University have resolved to confer
the degree of Doctor of Laws on the following : — Sir John
Neilson Cuthbe rison ; Mr. James G. Fraser, Fellow of Trinity
College, Camliridge; Mr. W. E. H. Lecky ; Mr. David
Robertson, Millport; Dr. T. E. Thorpe, F.R.S. ; Surgeon-
Major Lawrence A. Waddell, I. -M.S., Bengal.

The ninth Session of the Edinburgh Summer Meeting is
arranged 10 take place in August. Prof. Geddes and Mr.
William Sfiarp lecture in the section of Philosophy, .Social
Science, and Anthropology ; and the prospectus also inchiies
the name~ of M. Demolins, editor of the Science Sociale, of Dr.
Wenley, Dr. Delius, and others. Under Civics and Hygiene
are the nanus of Dr. Dyer, M. Paul Desjardins, M. Elisee
Reclus, Dr. Irvine, Miss Jare Hay, and Dr. Stephens. Mr.
Goodchild and Mr. Herbertson undertake the dcp;iitment of
Geography in its widest st nse ; while Mr. J. Arthur Thomson
and Mr. Turnliull have charge of the Biology. There will be
many other features of interest, including a series of educational
conferences.

NO. I 326, VOL. 51]

The Professorshipof Natural History at the Royal .\giicultural
College, Cirencester, rendered vacant in December last by the
death of Prof. Harker, has now been filled by the appointment
of Mr. Theodore T. Groom, late Scholar of St. John's College,
Cambridge, and Lecturer and Demonstrator at the Yorkshire
College, Leeds. Mr. Groom at one time occupied the Cam-
bridge table at the Zoological Station, Naples, where he success-
fully carried out some valuable researches, the results of which
were communicated to the Royal Society of London, and
(lublished in their Philosophical Trainactioiu. The chair of
Natural History at the College has been filled by a succession of
very able men, among whom, in addition to Prof. Harker, may
be mentioned such names as Buckman, McNab, and Thiselton-
Dyer.

SCIENTIFIC SERIALS.

American yoiirnal of Science, Match. — The Appalachian
type of folding in the White Mountain Range of Inyo County,
California, by C. D. Walcott. In the broad palaeozoic area
between the Sierra Nevada on the west and the early paLTiozoic
shore-line on the east (Colorado) a period of folding and
thrust-faulting was followed by a peiiod of vertical faulting,
which displaced the strata that had been folded and faulted in
the preceding epoch. The extent and character of this dis-
turbance can only be determined by a careful study of each of
these mountain ranges for a distance of over five hundred miles
east and west, and probably one thousand miles noith and south.
— The succession of fossil faunas at Spiingfield, Missouri, by
Sluail Weller. The rocks studied are teds of grey limestone
with lenticular chert concretions, and form part of the
Mississippian series. The faunas of the lower part of the
section may be correlated with the Burlington faunas of Iowa,
and those of the upper part with the Keokuk faunas. The
whole series of faunas is continuous, and the whole series of
rocks should be designated by a single name. The term Osage,
suggested in 1S91 by II. S. Williams, is recommended. —
Drift boulders between the Mohawk and Susquehanna rivers,
by A. P. Brigham. The Archaean and the more northern
Palsczoic fragments are strewn over the whole district at all
altitudes, but diminishing southward in size, and sparse in
amount on the highest hills, especially to the southward, where
the tops of the ranges are often surprisingly free from trans-
ported ma'erial. .Actual reduction of the general surface
towards base level doubtless proceeded rapidly duiing glacial
time, but even then the process was rapid only in the geological
sense, and the result a minute fraction of what has been accom-
plished since the region became a land surface.

Bulletin of the American Mathematical Society, vol. i. 5.
(New York, February 1895.)— On a certain class of canonical
forms, by Mr. R. \. Roberts, is a paper, read before the
Society at its December meeting, which treats of an interesting
class of theorems occurring in the consideration of algebraical
quanlics. — " Ha) ward's Vector Algebra" is a review, by Prof.
M. B<jcher, of the algebra of coplanar vectors and trigono-
metry, which deals out praise and its opposite in about equal
proportions. — Ai^olar triangles on a conic is a very interesting
paper by Prof. F. Morley. — The remaining short notices com-
prise an instance where a well-known test to prove the sim-
pl city of a s:mp!e group is insitfiitient, by G. H. Miller, and
an account of the Lobachevsky Memorial Volume, 1 793-1893.
Amorgst the notes is a bare statement of Prof. Cayley's death.
— The usual new publications list concludes the number.

Symons's Monthly Meleoi ological Magazine for March con-
tains another striking piool of the severity of the frost in
February last, as shewn hy the temperature of the earth at
Camden Square, in the rorih-west cf Lon'cn. The ther-
mometer w ith its lulb one foot below the surface was first read
on January I. 1S71. Prior to 1895, it was never below 32', and
only reached that point in 1S80. But in February last there
weie twelve ccnsecuiive days on which the thermometer was
1 elow 32'. In country districts, the frost penetrated to a much
greater depth, and this sufjcct will prcbably be referred to in a
future number of the magazine. A careful observer at Bcrk-
hamsted states that the frost there penetrated to a depth of
I f ot S inches.

Internationales AicJ.iv Jiir Elhi.igiajl.ie, Band. vii. Heft
V. and vi. 1804.— Piof. H. H. G'glioli, in his "Notes on seme

;26

NA TURE

[March 28, 1895

reiaarkable Specimens of Old Pemvian ' Are Plumaria,' " gives
a description of two veiy fine heed-dresses in Ancient Peruvian
feather wcik, which are illustrated by a beautifully executed
coloured plate. It is strange, as the author points out, "that
the sptcimens of old Peiuvian 'ars plumaria' unearthed from
the hundreds of huacas, excavated but too often by vandalic
treasure-seekers, have not attracted more attention." The best
specimens of feather-nosaic were made in the sixteeiith and
seventeenth centuries, and the ait has new practically died out.
—Mr. S. H. Ray al stiacis and annotates "Some Notes on the
Tannese," by Rev. W. Giay. Mr. Gray has been a missionary
in Tanna for twelve years, and so he can speak from adequate
personal knowledge; he gives infoincation on diess, circum-
cUion, political crgEnisalion, war, kava, religion, social
organisation and marriage, the calendar, the winds, and
language. This is a valuable supplement to Dr. Codrington's
monograph ; the section on religion is of especial value. Dr.
H. Ten Kate describes and illustrates a collection of ethno-
graphical oljecis ficm the Timor Group. The suppleiiient to
vol. vii. of the ArcUtv is an account of the Narg, or the Siamese
fhadow-figures in the Volkerkunde Museum in Berlin, by Dr. F.
W. K. Miiller. A transcripticnardlranslation (inGeiman)of the
rhymtsof the drama is given, which is a fragment of the Kama-
jana. It is illusltaled by eleven plaies, eight of which are
coloured. Vol. viii. ccn merces wilh the conclusion of Dr. Ten
Kate's paper, which is illustrated by four plates. This part is of
more geceral interest, as it deals partly with ihe religion and the
sacred an mals of the Timorese and other Indonesians ; the
author agrees wilh Pleyte, that the snake cult is indigenous to
Indonesia, ard is not bcircwed frcm India. There is a
useful little table of the distrilulion of certain objects. — S. K.
Kusnezow writes on the death-cult of the Tscheiemisse (a
Ural-Altaiic pet pie on the Volga, near Kazan). These
numbers of the Arihiv contain the usual valuable notes and
bibliography.

SOCIETIES AND ACADEMIES.

LO.NDON

Royal Society, Jai;uaty 17.— "On Slow Changes in the
Magnetic Peimeabihty cf Iron." ■"

By William M. Mordey.
The conclusions to which the observations lead, so far as
the y have gone, are : —

(1) The effect is not fatigue of the iron caused directly by re-
peated mpgnetic reversals— it is not " progressive magnetic

fatigue." ... . .

(2) Neither magnetic nor electric action is necessary to its
production. .

(3) It is a physical change resulting from long-continued
heating at a very moderate temperature.

(4) It appears to be greater if pressure is applied during
beating.

(5) It is not produced when the iron is not allowed to rise
more than a few degrees above the ordinary atmosphere.

(6) It is similar to the efTect produced by hammering,
rolling, or by heating to redness and cooling quickly.

(7) The iron returns to its original condition on re-annealing.

(8) It does not return to its original condition if kept unused
and at ordinary atmospheric temperatures, whether the periods
of rest are short or long. ,, „ ,,

March 7— "The Action of Heat upon Ethylene, II. Uy
Prof. Vivian B. Lewes.

From the results of the experiments described in the paper it
is stated that :^

(1) The initial decomposition of ethylene by heat is very rapid,
and requires but a shoit flow through a heated containing vessel,
such primary decomposition, however, being but slowly com-
pleted, owing to secondary reactions, which lend to reform
elhylene.

(2) Dilution has but little effect in retarding the decomposi-
tion of elhylene, unless it be very large.

(3) Incicase in rate of flow diminishes the amount of dccom-
po»iti<n whin the heated area IS small, but rajiidly dimini>hes
ID efftcl as the length of flow through a heated area increa.ses.

(4) The decomposition of ethylene is chu fly caused by radiant
heat, the efiect ol which is very great as compared with the de-
composition due to contact wiih heated surfaces.

March 21. — "The Cause of Luminosity in the Flames of
Hydrocarbon Gases." By Prof. Vivian B. Lewes.

NO. 1326. VOL. 51]

The facts which appear lo be established in this paper are : —

(1) That Ihe luminosity of hydrocarbon flames is principally
due to the localisation of the heat of formation of acetylene in
the carbon and h\drogen produced by its decomposition.

(2) That such jocaiisation is produced by the rapHiiy of its
decomposition, which varies wilh the temperature of the flame
and the degree of dilution of the acetylene.

(3) That the average temperature of the flame due to
combustion would not be sufficient 10 produce the incandescence
of the carbon particles within the flame.

In a paper on the action of heat upon ethylene, broucht
before the Royal Society this spring, the author showed that
the decomposition of ethylene into acetylene and simpler
hydrocarbons was mainly due to the action of radiant heat, and
was but little retarded by dilution, whilst he ha^; shown in this
paper that the acetylene so produced requires a considerable
increase in temperature lo bring about its decomposition \\hen
diluted, and it is possible with these data to give a fairly
complete description of the actions which endow hydrocarbon
flames with the power of emitting light.

When the hydrocarbon gas leaves the jet at which it is being
burnt, those portions which come in contact with the air are
consumed and form a wall of flame which surrounds the issuing
gas. The unburnt gas in its pa'sage' through the lower heated
area of the flame undergoes a number of chemical changes,
brought about by the action of ladiant heat emitted by the
flame walls, the principal of which is the conversion of the
hydrocarbons into acetylene, methane, and hydrogen. The
temperature of the flame quickly ri^es as the distance from the
jet increases, and a portion of the flame is soon reached at
which Ihe heat is sufTiciently intense lo decompose the acetylene
with a rapidity almost akin to detonation, and Ihe heat of its
formation, localised by the rapidity of its decomposition, raises
the liberated carbon particles to incandescence, this giving the
principal part of the luminosity of the flame ; whilst these
particles, healed by the combustion of the flame gases, still
continue to glow, until finally themselves consumed, this
external hcnling and final combustion adding slightly lo the
light emitted.

Any unsaturated hydrocarbons which have escaped conversion
into acetylene betore luminosity commences, and also any
methane which may be present on passing into the higher
temperaluies of the luminous zone, become converted there into
acetylene, and at once bL-ing decomposed to carbon and
hydrogen, increase the area of the light-giving portion of the
flame.

" On the Changes in Movement and Sens.ition produced by
Ilemisection of the Spinal Cord in the Cat." By C. D.
Marshall.

"On the Analysis of Voluntary Muscular Movements by
certain new Instruments." By Dr. W. R. Jack.

"On the Spark Spectrum of Argon as it appears in the
Spark Spectium of Air." By Prof. W. N. Hartley, F.R.S.

Chemical Society, March 7. — Dr. Armstrong, President,
in the chair. — The following papers were read : — Dimethyl-
ketohexanuthylene, by F. S. Kipping. This substance is a
colourless oil boiling at 174-176°, and is prepared by dis-
tilling calcium oa'-dimethylpimelate with soda-lime. — The use
of barium ihiosulphate in standardising iodine solution, by
K. T. Plimpton and J. C. Chorley. Barium ihiosulphate,
BaSjOa, 11^0 is well .adapted for standardising iodine solution,
inasmuch as it keeps well, has a high molecular weight, and is
readily acted on by iodine. — The melling points of racemic
modifications and of optically active isomerides, by F. S.
Kipping and W. J. Pope. Dextro-rotatory and racemic
ir-monobromocamphor melt at the same lempeiaiure, and the
melting point of the one is not depressed by the presence of
the other isomeridc ; the same is true of the inactive and
dextro-rotatory irmonochlorocamphors. — Phenyl elhers of
methylene- and ethylene-glycols. Synthesis of a methyl-
butyrolaclone, by E. Haworih and W. H. Pcrkin, jun. A
numlier of phenyl ethers of methylene- and ethylene-glycol
have been obtained by the use of sodium jihenate ; aincthyl-
bulyrolactone has been synthesised from chvlic sndinnictliyl-
malonate.- Mctliylisobuiylacetic acid, ClI.Mc, CM.. ClIMe.
COOIl, by W. II Bcnilcy and M. W. Hurrows. This acid
was prepaicd by tin- distillation of methylisobuiylmalonic acid,
which in turn wa.s synthesised from elhylic sodiomcthyl-
malonate and isobulyl bromide.

March 2S, 1895]

NA rURE

3^/

Geological Society, March 6.— Dr. Henry Woodward,
F.K.S., President, in ihe chair. — .A. new ossiferous fissure in
Creswell Crags, by W. L. H. Duckworth and F. E. Swainson.
The fissure explored by the authors is about 30 feet above the
level of the artificial lalce at Creswell Crags. .\t the top occurred
a white ear'h (with human and other remains) passing down
into a red sand with remains of fox, badger, roe-deer, and other
mammals. Beneath the latter deposit, and separated from it
by a fairly sharp line of demarcation, came the cave-eirlh
proper with palieohthic implements and bones of Rhinoceros
Ikhorhiniis, Bison prisciis, C/ysiis spehciis, //y,c>i,i, crociita var.
spe!<ea, and Ccrviis laranJus. The authors suppose that this
cave-earth was derived from an older deposit, and had been
transported to its present place by water, though there is evi-
dence that the transport had been from no great distance. Con-
sequently they followed the fissure inwards, until brought to a
stop by a mass of travertine, which they penetrated with a
small hole. They hope to explore the fissure beyond this tra-
vertine on a future occasion. — Notes on the chemical compo-
sition of some oceanic deposits, by Prof. J. B. Harrison and
A. J. Jukes-Browne. The authors formerly experienced great
difficulty in comparing their analyses of the oceanic deposits of
Barbados with those of modern oozes made by Dr. Brazier.
.Since then Dr. Murray ha> placed samples of recent red clay
and Ghbigerina-ooze at their disposal, and these were analysed
by Prof. Harrison and Mr. John Williams. The results of
analysis of the red clay were arranged as follows : — -Vrgillaceous
constituent 67S5 per cent., pumiceous matter 23'26 per cent.,
organic constituents 5'SS, and adherent sea-salts 3'6l per cent.
The authors found that the argillaceous constituent was not a
mixture of an orthosilicate of alumina and hydrated peroxide
of iron, having the proportion of silica to alumina as 14 to 12,
but a more highly silicated compound in which the proportions
were as 33 to 12. It was in fact a ferruginous earth, such as
would result from the decomposition of palagonite and of a
basic volcanic glass, fragments of which were frequent in the
Pacific red clays. The pumiceous matter was the debris of an
acid pumice containing 7 per cent, of soda, and apparently
therefore the pumice of a sodi-fclsite. Comparing the analyses
uf the recent red clay with those of Biroadian red clays, they
find the differences to be such as would result from mixtures of
the pala^oniiic earth with various acid and basic pum ices. A
mixture of the palagonitic earth with the pumiceous dust which
fell on Barbados in 1S12 would have a composition closely cor-
responding to that of the oceanic clay of Barbados. The recent
calcareous ooze closely resembled the more calcireous " chalks"
of the Barbadian oceanic series, but the latter contained much
colloid silica and fine clay. The differences between the analyses
of the recent ooze and of English chalk, when certain allow-
ances are made, were found to be but small. The recent
calcareous ooze contained many more G/oii^c-rim-iesis than
tertiary or mesozoic chalks, but it is suggested that this is due
to our possessing only the surface-layers of the Globigerina-
ooze. In one important respect all the different kinds ol deposit
which were examined resembled one another, namely, in the
infinitesiiiially small quantity of quartz which they contained.
The authors' examination of the recent oceanic dep isits, and a
-omparison of them with the raised Barbadian deposits, only
increased their conviction that the latter were of truly oceanic
origin.

Linnean Society, March 7.— Mr. C. B. Clarke, F. R.S. ,
President, in the chair.— Mr. A. Henry was admitted a Fellow .
—On behalf of Sir Joseph Hooker, the Secretary exhibited a
ironze medal struck in honour of the late Alphonse deCan-
lolle. — -Mr. J. E. Harting exhiiiited a remirkable head and
lorns of Cupra irgagnis recently obtained by Mr. F. C.
Selous in Asia Minor, and made remarks on the geographical
lisiribution of this and other allied species. — Mr. G. F. Scott
lliot, who had been absent from England since Sepiem bcr
S93, on a botanical exploration of Mount Ruwenzori an 1 the
:ountry to the north of the Albert Edward Nyanza, gave an
iccount of his journey and 'if the results, geographical,
lotanical, zoological, and p litical, obtained by him. The
:ountiy lying north-east of the Vicioria Nianza was described
IS a large, rolling, grassy plain, some 6000 feel above sea-level,
ind well adapted for colonisation. He went .we-t from the
Victoria N\anza to Mount Ruwenzori, which is said to have an
iltitudeof iS, 000 feet, and spent four months in exploring ihnt
listrict undir the great disadvantage of a dense cloud hanging
iver the mountain the greater part of the day, which often pre-

NO. 1326, VOL. 51]

vented the party from seeing more than fifty feet ahead. The
sides of the mountain were clothed at the base with a thick
growth of trees resembling the laurel of the Canary Islands;
above that, bamboos to the 10,000-feet level ; and above that
again what Ihe explorer could only liken to a Scotch peat moss
in which the traveller sank at every step a foot or more. Large
trunks like those of /snViz arborea of the Canary Islands, but
indicaling trees 80 feet high, were noticed. Amongst other
plants found were a Viola, a Cardamine, a gigantic Lobelia, at-
taining a height of five or six feet, an! a species of Hypcrietim
resembling that found in the Canaries ; indeed, the similarity of
the flora to that of the Canary Islands was remarkable. Mr.
Scott Elliot ascended Mount Ruwenzori to the height of 13,000
feet, finding evidence of animal life and numerous insects to a
height of 7000 feet. Above 10,000 feet his Swahili porters
could not sleep without injury to their health, and it was only
with a reduced number of men that he was able to ascend
another 3000 feet. Amongst the animals specially mentioned
was a species of water buck {Cobm), a new chameleon, a new-
snake, and several new insects. — The Secretary then read an
abstract of a paper by Dr. .Maxwell T. Misters, on the genus
Cupiasus, illustrated by a number of plants and cuttings which
had been forwarded by Messrs. Veitch, Mr. Moore, of Glas-
nevin, and Dr. Acton, of Kilmacurragh. — Dealing with the
zoological collections made during the recent expedition of Mr.
Theodore Bent to Southern Arabia, Messrs. Kirby, Gahan, and
Pocock presented papers on the inserts and arachnida which
had been obtained, som2 of which were des;ribed as new.

Royal Meteorological Society, March 20. — Mr. VV. X.
Shaw, F.R.S., delivered a lec'.ure on "The Mjtion of Cloud?
considered with reference to their mode of formation," which
was illustrated by experiments. The qaestioa proposed for
consideration was how far the apparent motion of clDud was a
satisfactory indication of the motion of the air in which the
cloud is formed. The mountain cloud cap was cited as an
instance of a stationary cl >ud formed in air moving sometimes
with great rapidity; ground fog, thunderclouls, and cumulus
clouds were also referred to in this connection. The two
causes of formation of cloud were next considered, viz. (i) the
mixing of masses of air at different temperatures, and (2) the
dynamical cooling of air by the reduction of iis pressure with-
out supplying heat fron the outside. The two methols of
formation were illustrated by experiments. A sketch of the
supposed motion of air near the centre of a cyclone showed the
probability of the clouds formed by the mixing of air being
carried along with the air after they were formed, while when
cloud is being formed by expansion circumstances connected
with the formation of drops of water on the nuclei to be found
in the air, and the maintenance of the particles in a state of
suspension, make it probable that the apparent motion of such
a cloud is a bad indicator of the motion of the air. After
describing some special cases, Mr. Shaw referred to the
meteorological effects of the thermal disturbance which must be
introduced by the condensation of water vapour, and he
attributed the violent atmospheric disturbances accompanying
tropical rains to this cause. The difference in the character of
nuclei for the deposit of water drops was also pointed out and
illustrated by the exhibition of coloured halos formed under
special conditions when the drops were sufficiently uniform in
size.

Paris.

Academy of Sciences, March iS. — M. Marey in the
chair, — .-Yttcmpts to produce chemical combinations with
argon, by M. Berthclot. Argon has been submitted to the
action of the silent discharge under the conditions described in
Ihe author's " Essai de Mecanique chimique," t. ii., pp.
362-363. The app.aratus used was that described in the
" Annales de Chimie et de Physique" [5], x., pp. 79, 76, and
77. With benzene vapour, argon is absorbed though more
slowly than nitrogen. 87 per cent, of the volume of argon
employed in the experiment entered into combination. As the
total volume of argon at disposal was but 37 c.c, the products
were too small in quantity to allow of any extenried investiga-
tion into their nature. They appear to be similar in character
to the products obtained with nitrogen and benzene. A yellow,
resinous, odorous substance condensed on the surface of the
two glass tuhes ; this substance decomposed on heating, yielding
an abundant carbonaceous resi lue and volatile products which
reddened litmus paper. — On the iacunse in the zone of small
planets, by M. O. Callandreau. — Transformations of fibrin by

^:S

NA TURE

[March 28, 1895

the prolonged action of dilute saline solutions, by M. A.
Dastre. — On the variations of terrestrial latitudes, by M. F.
GonnessiaL — On the theory of a system of differential equations,
by M. A. J. Stodolkievitz. — On a general definition of fric-
tion,, by M. Paul Painleve. — On Fourier's problem, by M. Le
Roy. — .\bsorption of light in uniaxial crystals, by M. G.
Moreau. The symmetry of uniaxial absorption is not so com-
plete as the theory of the ellipsoid of absorption indicates. The
dissymmetry is greater as the crystal is more birefringent. —
On the potential of an electrified surface, by M. Jules
.\ndr.-iJe. — .\pparatus imitating the movements executed by
certain animal? in turning round without external fulcra, by
M. £dm. Fouche. The explanation of the movements of a cat,
enabling it lo always fall on its feet, given by M. Guyou, i'i
completely borne out by the successful repioduction of the
rotatory movement with a strictly mechanical model. — The
catoptric and symmetrical objective, by M. Ch. V. Zenger. — On
a class of secondar)' batteries, by M. Lucien Poincare. The
author describes a secondary battery with mercury for poles and
sodium iodide in concentrated solution for electrolyte. The mer-
cury iodide formed remains in solution, and the soJium forms
an amalgam with the mercury. On discharge the yield is more
than 90 per cent, of the theoretical. The battery is not affected
by short circuiting or the particular manner of its discharge, but
is unlikely to be practically used on account of the expensive
nature of the materials, and the necessity of removing the amal-
gam from contact with the liquid if the battery is to remain long
charged. — On the effect of an alternating electromotive force on
the capillary electrometer, by M. Bernard Brunhes. — Thermo-
chemical carbon battery, by M. Desire Kordi. By the action of
carbon on barium peroxide during the reduction of the latter to
monoxide, an E.M.F. of nearly I volt is produced when ar-
ranged as a cell. In the case given an internal resistance of
13*6 ohms was found. A similar arrangement with cop.
per peroxide, the latter being separated from the carbon
pole by dry, pure potassium carbonate, gave I'l volt with
an internal resistance of 3"2 ohms. — Action of nitrous
oxide on metals and metallic oxides, by MM. Paul
Sabatier and J. B. Senderens. A table is given showing the
comparative reactions of NjO, NO, and NO;, and air on a series
of metals and oxides. The deduction is drawn that oxidations
by means of N^O are caused by the direct action of this gas
without preliminary decomposition into its constituents. — Re-
searches on the heats of combination of mercury with the
elements, by M. Raoul Varet. — On the isomeric states of the
oxides of mercury, by M. Raoul Varet. It is shown that yellow
and red oxides dissolve in dilute IICX with liberation of the
same amount of heat, and hence the transformation of yellow
into red oxide gives no appreciable thermal effect. — On the heat
of formation of some compounds of iron, by M. H. Le
Chatclicr.— On the chlor-aldehydes, by M. Paul Rivals. A thcr-
mochcmical paper. — On a mercuric combination of thiophene,
permitting the estimation of the latter in commercial benzene
and its extraction therefrom, by M. G. Deniges. .\ very stable
combination of mercury and thiophene, having the composition
(SO4Hg.Hg0)jSC4H^.H;O, is obtained by treatment of thio-
phene with an acid solution of mercuric sulphate (made by dis-
solving fifty grams of mercuric oxide in 200 c.c. of pure sulphuric
acid diluted with a litre of distilled water). On account of its
insolubility and ease of formation, this compound may be used
for the detection of traces of thiophene in benzene and for the
purificaiion of benzene. — On the amorphous stale of melted
substances, by M. C. Tanret. — Derivatives of active a hydro-
xybulyric acid; by MM. Ph. A. Guye and Ch. Jordan. A
paper K'*'"!? optical rotations and products of a'-ymnielry. —
The production of wine and the utilisation of fertilising prin-
ciples by the vine, by M. A. Muntz. — On the decortication of
wheal, by M. P.alland.— On the parts taken respectively by
purely physical and bjr physiological actions in the disengage-
ment of carbonic acid by muscles isolated from the body, by
M. J. Tissot. — Therapeutic action of currents of high frequency
(auloconduction of M. d'Arsonval), by M.M. .'\postoli ami
Berlioz. These currents have a powerful influence on the nutri-
tive activity of the tissues, and hence are of first importance in
the treatment of many functional troubles, caused by deltctive
nutrition. — New application of the graphic method to music, by
MM. A. Binel and J. Courtier. — Ili-tological researches on the
devcl pmcnt of the Mucorini, by M. Maurice Leger. — On the
l;eology of Ossola (Atpn l.ipontini), by M. S. Travcrso.— On
an application of photography to oceanography, by M. J.
Thoulet.

BOOKS, PAMPHLETS, and SERIALS RECEIVED

Books. — Bird Mores: late J. M. H.iyward (Longmans).— Statesman's
Vear-Biiok, i895(Macmillan). — 0"-'^titati\c Chemical Analysis of Inorganic
Substances (American Book Company, New York). — Annals of British
Geology, 1893: J. F. Blake(Dulau)— A Handbook of Systematic Botany:
Dr. E. Warming, translated and edited by Prof.M.C. Potter(Sonnenschein).
— Illustrations of the Zoology of H.M. Indian Marine Surveying Steamer
Inrfsti^alor. Part i (t^u.iriich). — Stanlord's Compendium of Geography
and Travel (new issue)— Africa, Vol. i ; North .Africa : .A. H Keane
(Stanford). — Hygienische Meteorologie : Prol. Dr. W. J. van Bebber
(Stuttgart, Enke). — Text-Book of Anatomy and Physiology f'r Nurses:
O. C. Kimber (NIacmilUn). — Chemical Analysis of Oils, Fats, Waxes, &c. :
Dr. R. Benedikt, revised and enlarged by Dr. J. Lcwkowitscli(Macmillan).
Taschenbuch fur Flugtechnikcr und I.uftschiffer: H. W. L. Moedebeck,
(Berlin, Kuhl). — Le Piiirole, L'Asphalte et le Bitumc : A. Jaccard (Paris,
-Alcan).

Pa.mphlets.— Madras Government Museum. Bulletin No. 3 : RAm6-
varam Island and Fauna of the Gulf of Manaar ; E. Thurston, 2nd edi-
tion (Madras) —Die Entwickelung ; Dr. G. Pfeffer (Berlin, Friedlander),

Serials. — Royal Natural History, Part 17 (Warne). — Proceedings of ihe
Koyal Society of Victoria. Vol. vii. new scries (Melbourne). — American
Naturalist, March (Philadelphia). — Astrophysical Journal, March (Chi-
cago),— Journal of the Institution of Electrical Engineers, No. 115, Vol.
xxiv. (Spun). — Economic Journal, March (Macmillan). — Botanische Jahr-
bucher, Neunzehnter Band, v. Heft Leipzig, Engelmann). — Transactions
of the Astronomical and Physical Society of Toronto for the Year 1894
(Toronto, Kowscll). — Zeitschrift fi'ir PhysikalischeChemie, xvi. Band, 3 Heft
(Leipzig, Engelmann). — Minnesota Botanical Studies, Bulletin No. 9
(.Minneapolis).- Notes from the Leyden Museum, Vol. xvi. Nos. 3 and 4
(Leyden. Brill).— Good Words, April (Isbister).— Sund.iy Mag.-i7ine, April
(Nbister). — Longman's Magazine, .^pril (Longmans). — Quarterly Journal of
Microscopical Science, No. 147 (Churchill). — Hulletinol the Geographical
Club of PhiLidelphia, Vol. i. No. 3 (Philadelphia).— Bulletin of the U.S.
Geological Survey, No. 120 (Washington).

CONTENTS. PA.L

Orb-Weaving Spiders of the United States. My

Rev. O. P. Cambridge, F.R.S 505

The Sea and its Coasts 507

The Chemistry of Cod-liver Oil. By Jas. Cameron 508 i
Our Book Shelf:— '

Wislicenus : " Aslronomische Chronologie." — W.

J. S. L 509

Hellmann : " Die altesten Karten der Isogonen, Iso-

clinen, Isodynamen" 5°9

Briggs : "An Elementary Text-book of Hydro-
statics" 5°9 I

Letters to the Editor: —

The Statistical Investigation of Evolution.— J. T,

Cunningham . • ... 510 -

A True Spectrum Top and a Complementary One. —

Dr. C. Herbert Hurst 5'° |

A Koucault Pendulum at Dublin.— W. R. 'Westropp |

Roberts S«0 1

Snake Cannibalism.— J. Schonland SII I

American Freshwater Sponges in Ireland. — Dr. R. j

Hanitsch 5" '

Peripatus in the West Indian Islands.— J. H. Hart , 511

PLauetary Photography.— C. T. 'Whitmell .... 511

Cle.ining Tobacco Pipes.— Cecil Carus- Wilson . SIlj
The Habits of Limpets. By Prof. J. R. Ainsworth

Davis S"|

Terrestrial Helium (?) 5'» j

Notes S'3j

Our Astronomical Column : — 1

The Moon and Atmospheric Waves S'*

Stellar Photography 5'°

Stanilard Time in Australia 5'°l

Nova Auriga: 5'"'

New Compounds of Hydrazine with Fatty Acids.

By A. E. Tutton 5'

The Aurora of March 13 S'7

The U.S. Units of Electrical Measure ( >KiV/< Diagram) 518
On the Nature of Muscular Contraction (Willi

Dinsnams). liy Prof. Th. W. Engelmann .... 5'

The Snail Fauna of the Greater Antilles S24

University and Educational Intelligence 5'.'

Scientific Serials 5'!

Societies *nd Academies 5'

Books, PampQlets, and Serials Received .... 1-'

NO. 1326, VOL. 5 1]

NA TURE

529

VERWORN ON GENERAL PHYSIOLOGY.

Allgemeine Physiologie. Ein Grundriss der Lehre vom

Leben. Von Max Verworn. (Jena : Fischer, 1895.)

THIS handsome and well-illustrated volume of some
six hundred large octavo pages, by a young German
physiologist already favourably known by his special
researches, is a mbilious in design but praiseworthy in
purpose. The aut hor complains of the too narrow
iharacter of most of the physiological inquiries and
writings of the present time ; and not without some jus-
tice. A cursory reader of a modern text-book of physi-
ology (of my own, for instance), might easily come to the
conclusion that most of our current physiological doc-
lines had been arrived at by the exclusive study of the
rog, the rabbit, and the dog, with occasional help from
hat of the horse, of a fish, of a bird, and of man. All
;he wealth of opportunity for observation and experiment
offered by the innumerable other forms of life, seems to
)e neglected. And there follows naturally the inference
that physiology would gain a healthier tone and broader
^rasp, by widening the field of its study. Years ago the
Ljreat Johannes Miiller, in his immortal work, took such
I broad survey; later on. Carpenter followed the same
course in his " Comparative Physiology," a work to which
[, at least, owe much ; and now Dr. Verworn attempts
to present, in a general view, the light which the multi-
tudinous special researches of more recent days have
shed on the fundamental phenomena of life.

A very little reflection will show that when the mean-
ing of the term physiology is carried beyond the bounds
which academic conditions have fixed for it, it becomes
difficult to say what parts of the knowledge of living
beings are not embraced by it. A physiologist, with-
drawing himself from the immediate demands of the
schools, and brooding over the many aspects of his
science, cannot help feeling that all inquiries into the
phenomena of life end by taking the form of physiological
Miquiries. While morphological facts may ,in the first
instance, and for a while, be regarded by him chiefly
as helps towards the solution of special physiological
problems, he cannot help believing that the ulti-
mate interpretation of the phenomena of form must
be based on the principles of that fundamental phy-
siology, which, for want of a better word, we may call
molecular. And, even at the present time, imperfect as
physiology as yet is, some of us may think that some
modern morphological speculations have gone astray,
through heed not being given to what even a narrow
imperfect physiology is already able to teach.

Hence, Dr. Verworn, taking as the title of his book
" General Physiology," has naturally been led to dwell
on many topics which are not to be found in a treatise
of narrower scope. After a very brief historical sketch,
and a chipter on the composition or nature of living
matter, in which he discourses on the "cell" and its
constituents, and on the physical and chemical properties
of living matter, as well as on the differentials of living
and lifeless matter, he proceeds to the consideration of
NO. 1327, VOL. 51]

the elementary phenomena of life. These he treats
under the heads of change of substance (metabolism),
change of form, in which such topics as heredity,
adaptation, cell division, reproduction and the like
are dealt with, and change of energy. Then follows
a chapter on "The General Conditions of Life," in
which, among other matters, he treats of the origin
of life on the globe, and the history of death. " Stimuli
and their effects" are next discussed, and the final
chapter is headed the " Mechanism of Life."

Even six hundred goodly pages furnish all too small a
room for such a treatment of each of the many and
varied topics handled in them as would in each case
appear adequate to those who had made them the
objects of special study. Moreover, the author, as he
states in the preface, has striven to write in such a way
that the reader should not be easily wearied ; and the
practised writer knows that a simple way of not weary-
ing the reader is by a light touch, so to brush away all
difficulties as to lead the reader to think he grasps
clearly that which, in reality, no one truly understands.
The author further, as he also states, addresses himself
not to physiologists, or even to biologists, exclusively, but
also to the cultured general reader ; and when a dis-
cussion about an abstruse physiological topic has to be
so conducted as to please the ear of the cultured general
reader, the special physiologist naturally finds the dis-
cussion spoiled by things which to him seem essential,
being left out, and by things which to him seem unim-
portant, or even irrelevant, being dwelt upon at length.
It would be ungracious, therefore, to find fault with the
particular way in which the author handles that or that
of the many themes with which he deals. For the same
reason, hesitation may be felt in objecting to the pro-
minence given in the work to definitions, some of which
a captious critic might urge had something of the mark
of barrenness, or to the frequently occurring judicial
"summing up" in paragraphs emphasised by spaced
type ; or to the abundant " generalisations," some of
which may be contested, while others appear to draw
perilously near to platitudes. The work, as a whole,
must commend itself highly to those morphologists who
desire to learn the more general and fundamental results
of recent physiological inquiry ; for the author has woven
into his work the very latest news from the physiological
laboratory. On the other hand, the physiologist, whose
activity has been too much limited to the study, by
complicated instruments of precision, of the phenomena
of the higher animals, who has moved too exclusively in
what some take pleasure in hall-marking as " horological
physiology," will largely profit by having his attention
directed to the many physiological questions which arise
in the course of morphological investigations, started by
observations recorded, for the most part, in periodicals
or works not falling within his ordinary reading. As
especially interesting, perhaps, may be mentioned the
chapter on stimuli and their effects, as illustrated by the
study of the simplest forms of life, and the discussion on
the part played by nuclei in the development of physio-
logical phenomena, in both of which matters the author
is able to appeal largely to his own observations. \'ery
suggestive also is the exposition of the doctrine of
assimilation and dissimulation and of its applications,

A A

530

NATURE

[April 4, 1S95

which forms a large part of the chapter dealing with
"the mechanism of life."

The author'claims for his work, that it is essentially an
exposition of " cellular physiology." I am myself inclined
to think that he exaggerates the value of this point
ol view. The idea of the cell, important as it has been,
and still is, when we deal with the cell as a morphological
unit, seems to me of much less importance when we deal
with it as a physiological unit. But I pass this over, in
order to join issue with the author on two other matters.
He speaks "of the impotence of the physiology of to-
day, when brought to face the simplest processes of life,"
and writes as if all the knowledge which, especially during
the last thirty years, has been gained by the application
of exact physical and chemical methods to the study of
the phenomena of life, simply led to the end of a blind
alley. He urges that, while we are rapidly approaching
perfection in these things, we yet are impotent in face of
the deeper problems. He even goes very near repeating
the taunt of the Philistine, "\Vith all your boasted pro-
gress, you are still unable to tell us -what life is" with,
however, the difference that he uses the taunt in order
to incite physiologists to adopt other methods of inquiry.
I venture to think; that in this the author is quite
wrong. Not only has the progress of physiology, due to
the use of exact methods, been remarkable during the
last half-century- or so, but also by those methods we have
been drawn measurably nearer the inner and hidden
mysteries. To take one instance among many, the
application of exact physical methods to the study
of muscles, so far from having brought us to a point
beyond which we cannot go, seems just now to
be opening up the way to fruitful conceptions of the
intimate nature of muscular contraction — conceptions
which would have been impossible in the absence of the
knowledge gained by the graphic method. Two armies,
from two different sides— one physical, the other chem-
ical—are attacking that difficult — to some it seems im-
pregnable—fortress. They have alreadyl gained many
of the outwoiks ; they are pressing on, drawing nearer to
each other ; and when they touch hards, they will do
that which will put to shame all scofis at their impotence.
Then again, the author finds fault with the prepond-
erant attention given by physiologists to the study of the'
higher vertebrate animals ; he blames them for their
comparative neglect of the lower and, especially, of the
lowest invertebrate forms. It is not for mc, who in my
rash youth had wild dreams of building up a new physio-
logy by beginning with the study of iheanuLba, and work-
ing upwards, to say one word against the experimental
investigation of the lower forms of life. Hut experience
and reflection have shown me that, after all, the physio-
logical world is wise in spending its strength on the
study of the higher animals. And for the simple
reason that in these, everything being so much more
highly differentiated, the clues of the tangles come, so to
speak, much more often to the surface, and may be
picked up much more readily. Taking again, as an
instance, the molecular processes which give rise to the
movements of animals, and which appear under such
forms as that of amn-boid movement, and that of the
contraction of a striated muscle, 1 venture to think that
the very apparent simplicity of the former is an obstacle

NO. 1327, VOL. 51]

to our getting a real grasp of its inner nature, and that
by our studies of the complex muscle, we are drawing
nearer to such a grasp than we could ever have done b\
observations confined to the phenomena of the amcx^ba
itself. And so in many other instances. The study of
the lower forms of life is, in reality, more dift'icult than
that of the higher forms : and the latter naturally comes
first. At the same time the author will have the sym-
pathy of :\11, if his contention be limited to the assertion
'• that the full fruition of physiological truth can only be
reached by the careful study of all forms of life, whether
high or low ; this, indeed, his own special investigations
have already shown, and in this sense the contribution
to a "general physiology," which his present volume
offers, is gladly welcomed by us all. M. Foster.

NERNSrS THEORETICAL CHEMISTRY.

Theoretical Chemistry, from the Standpoint of Avo-
iiadro's Rule, ami Thermodynamics. By Prof. Walter
Nernst, Ph.D. of the University of Gottingen. Trans
lated by Prof. Charles Skeele Palmer, Ph.D. of the
University of Colorado. Pp. XXV.-697. (London :
Macmillan and Co. 1895.)

NO one can compare the knowledge we possess
to-day of the conditions and general laws of
chemical change with the state of our knowledge ten
years ago, without being much impressed by the enormous
advances made in the last decade. .Accurate and
generalised knowledge of physical chemistry did not
exist ten or twelve years ago. What is practically a new-
science has arisen, based on the work of such men as
Guldberg and Waage, van't Hon', Ostwald, Arrhenius,
Nernst, Raoult, (iibbs, and Thomsen, who built upor»
the foundations laid by Dalton, Avogadro. Berthollet,
Faraday, Helmholtz, Thomson, and Clausius. The
special mark of the new science is that it has been pro-
duced, to use the words of Nernst, "by the co-operatiot>
of two sciences which hitherto have been, on the whole,
quite independent of each other." One hardly knows
whether to speak of physical chemistry or chcmicil
physics.

The text-book of this new science is Ostwald's " Lehi-
buch der Allgemeinen Chemie." Notwithstanding the
thoroughly satisfactory character of that work, there '
was room for another book which should treat the sub-
ject in less full detail, and which should pay especial 1
attention to the data and the conceptions that have been \
systematised and applied in a general way. Prof. Nernst
has written exactly the book that was wanted ; and this
book now appears in a form which brings it within the
reach of all English-speaking students.

The 7 hcorelical Chemistry oi Prof. Nernst deals with
(l) the universal properties of matter, (2) the atom and
the molecule, (3) the transformations of matter, and

(4) the transformations of energy. The first section
treats of (1) the gaseous, (2) the liquid, (3) the solid,
state of aggregation, (4) the physical mixture, and

(5) dilut; solutions. The second section is devoted to
(l) the atomic theory, (21 the kinetic theory of the mole-
cule, (3) the determination of molecular weight. 141 the
constitution of the molecule, (5) physical properties
and molecular structure, (6) the dissociation of gases.

April 4, 1895]

NA TURE

531

(7) electrolytic dissociation, (8) the physical properties
of salt solutions, (9) colloidal solutions, and (10) the
absolute size of molecules. Sections three and four are
concerned with the subject of affinity. The author treats
that part of this subject which is connected with the
transformations of matter under the headings : (i) the law
of chemical mass-action, (2) chemical statics in (a) homo-
geneous, and {h) heterogeneous systems, (3) chemical
equilibrium in salt solutions, and (4) chemical kinetics.
In dealing with the energetics of chemical affinity. Prof.
Nernst treats of (i) the applications of the first law of
heat, (2) temperature and (a) complete, {b) incomplete,
chemical equilibrium, (3) temperature and the velocity
of reactions, (4) heat and chemical energy, (5) electro-
chemistry, (6) photochemistry. An appendix contains
accounts of the more important developments of
theoretical chemistry in the year 1893.

The ground covered by the book is evidently very
large, and very different from that traversed by the
books on theoretical chemistry published ten years ago.
Theoretical chemistry, as understood by Nernst, is
based on Avogadro's law, and van't Hoffs extension of
that law to dilute solutions, the law of mass-action, and
the laws of thermodynamics. It would not be very far
from the truth to say that the book is concerned with
the meaning of the sign of equality in chemical equations,
and that the connotation of that sign is elucidated by
applications of the laws of Avogadro and van't Hoff, and
the law of mass-action, bound together and lighted up by
the laws of thermodynamics.

The essential characteristics of the book, so far as I
can judge, are the exceeding clearness in the statement
of each problem of theoretical chemistry, the cutting out
of irrelevant issues, and then the binding together of the
apparently detached discussions into an harmonious
whole by the application of the general principles of the
molecular-atomic theory, and of chemical energetics.

The treatment of osmotic pressure ,may be chosen as
an illustration of these characteristics of Prof. Nernst's
book. The meaning of the term osmotic pressure is
made clear on pp. 118-119, by the description of a theo-
retical experiment on the diffusion of sugar in aqueous
solution through a semi-permeable partition fitted with
a movable piston. Unfortunately, the translator has
rendered Losnngsmittel by " solvent material " ; had he
used the term " solvent " (as he does in some other
passages), the meaning would have been better conveyed.
Then follow lucid paragraphs on the methods of measur-
ing osmotic pressure (I wish the translator had not
allowed the phrase to pass, " ether containing consider-
able benzene"), admirably illustrating the bearings on
this problem of determinations of vapour-pressures, boil-
ing points, and freezing points. Having thus, by adher-
ing strictly to the problem under discussion, arrived at
a clear conception of osmotic pressure, the author pro-
ceeds, in a few brief and clear paragraphs, to consider
the circumstances which condition the osmotic pressures
of solutions, viz. the concentration of the solution, the
temperature, the nature of the dissolved substance, and
the nature of the solvent. The outcome of the matter is
then summed up in the statement — the lowering of the
freezing point of a dilute solution is proportional to the
number of molecules of the dissolved substance. This
NO. 1327, VOL. 51]

summary at once iiiggesls an inquiry into the range of
applicability of the law of osmotic pressure, and the laws
of solution in general ; and the inquiry leads to a state-
ment of van't Hoffs extension of the law of Avogadro.
The experimental det eimination of molecular weights by
the application of the \an't Hoff generalisation is de-
scribed (pp. 224-231) in that part of the book which deals
with the determination of molecular weights. When the
author comes to treat of dissociation he returns to the
subject of osmotic pr essure, and shows how an appli-
cation of the hypothesis of dissociation to salts in dilute
aqueous solutions leads to a far-reaching theory of
chemical change, and he propounds this theory in a clear
and practical manner. In one of the chapters dealing
with thermochemistry (pp. 565-567), the authcr, follow-
ing van't Hoff, b rings the subjects of osmotic pressure
and electrolytic dissociation within the range of thermo-
dynamical methods, and, by a fundamental equation,
connects the e quilibrium of a chemical system with such
conditions as temperature, pressure, and dissociation.
Had Prof. Nernst been tempted to discuss such a side
issue as the part played by the solvent in bringing about
electrolytic dissociation, he could not have arrived at the
very general results to which his strictly accurate and
limited method of inquiry have led him. He does, indeed,
devote a paragraph or two to this matter of the action of
the solvent {e.g. pp. 232, 444). He is careful to note the
great interest and importance of the question ; at the
same time he draws attention to the fact, often over-
looked, that no definite answer can be given to questions
regarding the existence of compounds of molecules of
the solvent with molecules of the dissolved substance by
the study of the osmotic pressures of dilute sclutions,
because the existence of such compounds would not
affect the os motic pressures of fairly dilute solutions.

Prof. Nernst dismisses the so-called hydrate theory
of solution in a short and somewhat contemptuous para-
graph (p. 444) ; he speaks of this conception as having
no theoretical basis, as having led to no general laws,
and as based on an uncritical examination of experi-
mental data.

A very admirable feature of the book is the care
taken to warn the student against drawing unsound and
inapplicable deductions from sound generalisations. For
instance, at the beginning of the chapter on the physica
prop erties of salt solutions (p. 331), the statement is
enun ciated that the properties of an aqueous solution
of a salt arc made up, additivcly, of the properties of
the free, ions. And then the illegitimate and misleading
inferences which may be, and some of which have been,
deduced f rom this generalisation are noted in a few
sentences, before the true meaning and applicabiHty of
the statement are developed.

I s hould like to deal at length with the author's treat-
ment of the law of mass-action, and the many appli-
cations and developments of this law ; but space forbids.
Among the applications of the law of mass-action I
would ask the student to note that which serves to explain
the discrepancies among the values for the strengths
of acids obtained by Ostwald by employing different
methods of measurement (p. 438).

The volume literally abounds in suggestions ; new
light is thrown on almost every question of theoretical

532

NATURE

[April 4, 1895

chemistry. When this book becomes generally known
and studied by English chemists, it seems to me it will
be impossible for any of them to refuse to acknowledge
the marvellous advances which have been made in
the science by the introduction of the conception of
electrolytic dissociation.

I would recommend every student of advanced
chemi jtry to study this work. Merely to glance through
it is little use : it must be studied laboriously ; and it will
well repay the labour. Of course there are weak parts
in the book. I think the treatment of the constHution
of the molecule is too sketchy ; and chapter vi. of Book
iv., on electrochemistry, should, in my opinion, have been
either expanded or omitted.

Of the translation it is difficult to speak advisedly.
I think the translator has attempted an impossible task,
the task, namely, of literally changing German into
English. If the meaning of sentences in one language
is to be conveyed in another language, it seems to me
that a paraphrase, not a so-called literal translation, is
needed. The task of translation must have been ex-
tremely difficult ; the subject-matter is complicated, and
German is not a language distinguished by its lucidity.
The meaning of the original is conveyed on the whole ;
but the sentences read strangely. See, for instance,
the most peculiar sentence near the bottom of page 591.
There is an extraordinary sentence about plucking
fruit from stepping-stones, on p. 354. Several cases
of absolute mistranslation are to be found ; for instance,
the sentence in italics in the ninth and tenth lines from 1
the bottom of p. 254, and the sentence at the beginning
of Book iii., p. 353. Beliebig is sometimes translated
" casual," sometimes " selected."

I admit the great difficulty of the task undertaken by
the translator : as I have said, he has generally suc-
ceeded in conveying the meaning of the original ; but I
think the rendering into English might have been at once
more accurate, more elegant, and more readable.

M. M. Pattison Muir.

OUR BOOK SHELF.

Bird Notes. By the late Jane Mary Hayward. Edited

by Emma Hubbard. Pp.181. (London: Longmans,

Green, and Co. 1895.)
Cataloi;ue of the Birds of Prey {Accipitrcs and Strides).

By j. H. Gurncy, F.Z.S. Pp. 56. (London : R. H.

Porter, 1894.)

A DAINTY book is Miss Hayward's, the pretty little pro-
cess-blocks, representing a number of our common birds,
matching the short sketches of avian habits. The
lamented author had a " deep-rooted love of the beauty
of the world." She was a close and unwearied watcher
of bird traits, and her notes possess the charm of all
original observations. From a scientific point of view,
the chief failing of many of the notes is that they endow
the birds too largely with human consciousness. Mrs.
Hubbard recognises the objection, and says something
in favour of this "anthropomorphism"; but while such
fancies are poetically attractive, and may be psycho- ;
logically justifiable, they must always be of less value
than the facts which give them birth. |

The ornithological papers of the late Mr. J. H Gurney |
were both numerous and important, and in the volume '

NO. 1327, VOL. 51]

under notice we have further evidence that the son
worthily carries on his father's interest in the collection
at Norwich Museum. All the birds of prey (hawks and
owls) in the Museum were catalogued by Mr. J. Reeve,
the veteran custodian, and from this MS. catalogue, and
his father's '' List of Diurnal Birds of Prey,' Mr. Gurney
has compiled thelistof Accipitresand Striges. According
to the list of the former order, the total number of exist-
ing species of diurnal birds of prey is now 470, of which
at least 89 are only sub-species. The total number of
existing species of owls is placed at 26S, of which 87
appear to be only sub-species.

Before each bird's name, in the two lists, a letter is
placed to mark the zoological region to which it belongs,
on Mr. Sclater's classification. A striking testimony to
the efficiency of this system is given by Mr. Gurney, in
the following words : " The way in which these several
divisions [Mr. Sclater's] are justified by the Birds of
Prey, and especially by the Diurnal Birds of Prey, is
remarkable, and if they were to be decided afresh by
that class of birds alone they could not very well be
improved upon. Seven-eighths of the Raptores are
found in one region only — i.e. not in more than one ;
and the region which has the greatest number is the
Neotropical or South American region, which contains
181 Hawks and Owls."
The whole of the Raptorial collection of Norwich

j Museum is now being transferred to Norwich Castle ;

■ and the completeness of the collection can be judged
from the fact that it comprises 403 out of the total of
470 accepted species and sub-species of Accipitres, and
195 out of 26S known species and sub-species of the
order of Striges. Mr. Gurney may well be proud of the
collection, and of the fine Castle Museum in which it is

I housed.

Prince Henry the Navif^ator. By C. Raymond Beazley, 1
M.A., F.R.G.S. (Heroes of the Nations Series.) I
(Putnam's Sons).

In this most interesting and valuable book, Mr. Beazley
shows us clearly the growth of geographical knowledge,
carrying his researches back earlier even than 130 A.D.,
he tells us that the first maps and charts of the old world
are due to Eratosthenes and -Strabo. Ptolemy succeeded
them, improved their work, and, where knowledge failed
him, ni.Tde errors himself; the author writes thus of his
g'eat chart: " Never was there a clearer outrunning of
knowledge by theory, science by conjecture, than in
Ptolemy's scheme of the world {c. a.d. 130)."

We gather much information concerning Greek and
Arabic geographers, of the early Christian pilgrims, and
of the discoveries of the Norsemen. Throughout the
book, we watch, as it were, the growth and improve-
ments of the maps and charts. We see the expansion of
geography due to the crusades and land travel. Finally we
are bro\ight to Prince Henry the Navigator himself. From
youth upwards, retired and studious, he withdrew him-
self at the age of twenty-one to his Naval Arsenal at
Sagres, and devoted the rest of his life to the accomplish-
ment of his three chief objects— "to discover, to add to
the greatness and wealth of Portugal, and to spread the
Christian faiih" We can but marvel at this great man,
at the untiring energy with which he worked, but still
more at the greatness of that work.

Mr. Beazley has treated the subject in a very thorough
and interesting manner, and the numerous maps form a
most important part of the book ; they date from
130 A.D.-1492. No pains have been spared to m.ake the
subject quite clear to the student. All ihtmigh the boolc
we see liow the dominion of the sea has been continu-
ously enlarged by the perpetual application of science
to the art of navigation. W.

April 4, 1895J

NATURE

533

An Elementary Treatise on Theoretical Mechanics.
Part iii. Kinetics. By Alexander Ziwet, Assistant Pro-
fessor of Mathematics in the University of Michigan.
(New York : Macmillan and Co., 1894.)

The first two parts of this excellent treatise have already
been noticed in these columns ; this third part keeps
up to the same excellence, and we look forward to a
sequel, in the absence of any indication that the treatise
is yet complete.

We think the author would have done well to have
followed the opinion of his American colleague, Prof.
T. \V. Wright, and to have reserved absolute measure-
ments to the Metric system of units, whileusinggravitation
units only with the British foot and pound. These last
units are too insular and provincial ever to be employed
in cosmopolitan problems where results have to be
translated into absolute measure ; and James Thomson's
word, potential, is never likely to be of any practical use.

Lagrange'sand Hamilton's generaldynamical equations
are expounded with clearness and elegance ; the ap-
plication of the principle of the Conservation of Areas to
the paradoxical motion of a kitten, let fall by his feet a
short distance above a table, has excited considerable
discussion recently at the Paris .Academy of Sciences ;
this problem would provide the author with an illustration
of the methods of generalised coordinates.

The copious list of authorities at the end of the chapters
is a valuable feature of the book. G.

LETTERS TO THE EDITOR.

I hi Eiitor lioes not hold himself responsible jor opinions ex-
pressed by his correspondents. Neither can he undertake
to return, or to correspond with the writers of, rejected
manuscripts intended for this or any other part of NATURE.
No notice is taken of anonymous communications. ]

Destruction of the Seismological Observatory at
Tokio, Japan.

I REGRET to say that a letter, which has just arrived from Tokio,
informs me that Prof. John Milne has lost all his valuable seis-
mographic instruments, with his library and many manuscripts,
through a tire which has occurred at his house and observatory.
Prof. Milne wishe> me to announce that his address-book has
been destroyed, but he will be able to forward vol. iv. of the
Seismological yoiirnal \.o \.\\o%t entitled to it, iflhey will send
in their names to him, " care of the Japan A/ail office, Yoko-
hama." He further wishes me to state that he has 600
damaged copies of the Seismological Society's Transactions,
and that from these he will be happy lo complete sets. Ap-
plicants for the copies of the Transactions should address Prof.
Milne, care of the Geological Society, Burlington House,
London, W.

I am sure that scientific men all over the world will feel the
deepest sympathy with Prof Milne in his great and, indeed,
irreparable loss. He was preparing to return to Europe when
the tire occurred, and he wishes to appeal to all who can furnish
him with separate copies of papers relating to earthquake
phenomena, to replace, so far as is possible, those he has lost
by the destruction of his library. John W. Judd.

April I.

On Mersenne's Numbers.

In 1644 the mathematician Mersenne asserted that out of
the 56 primes not < 257, there were only 12 primes, viz. : —

/ = l> 2, 3, 5, 7, 13, 17, 19, 31, 67, 127, 257,

which, taken as exponent (.7), make the number N = (2' - i)
also prime. No proof was published, and even up to now,
this statement has only been partially verified : the verification
is still one of the difficult problems of higher arithmetic. Ac-
cording to a paper by Mr. \V. W. Rouse Ball, in the Messenger of
Mathematics, vol. xx. p. 34, Mersenne's statement has been
verified (or the 18 prime values of </ < 60, and for 14 higher
values, and one additional number N has been shown to bo
prime l>y Prof. SeelholT, viz. when;/ = 61. This left 23 cases

NO. 1327, VOL. 51]

unverified, vi2. 3 supposed to be prime (when y = 67, 127, 257)>
and the remaining 20 .".upposed to be composite (when q — "I,
89, lOl, 103, 107, 109, 137, 139, 149, 157, 163, 167, 173, 181,
'93. 197. '99. 227, 229, 241).

I have recently discovered the verification of one of the latter,
viz. that

(2"'- i) is divisible by 74S7.

This can be readily verified directly by the method of Con-
gruences.

It has also been verified by actual division by Mr. R. Tucker
(Sec. London Mathematical Society), who has kindly sent me
the quotient consisting of 56 figures. The mode of discovery
of this factor has been communicated to the London Mathe-
matical Society, and will be sent to one of the mathematical
journals. ALLAN CUNNINGHAM.

March 23.

Tan-Spots over Dogs' Eyes.

I TRUST you will allow me to point out that the drift of my
letter on the above subject in Nature, vol. I. p. 572, has not
been fully apprehended. Hitherto we seem to have no very
clear cases in which we can actually trace the operation of
"natural selection." I think, when examined, this will be
found to be an instance.

The spots appear to have arisen in the dog as comparatively
recent permanent markings — for protective purposes — after semi-
domestication. .\s Mr. Worthington G. Smith says, they are
not seen among wild animals allied to the dog.

They appear to have arisen since the original Red Dog — be
he Dhole, Pariah, or Dingo — became pied, and at times black,
through domestication. It is only on a black coat that the tan-
spots would be conspicuous, and simulate eyes.

Perhaps Mr. A. R. Wallace may throw light on the matter.
The spots seem to be the only really permanent marking among
dogs, and are now being bred out. S. E. Peal.

Sibsagar, Asam, February 19.

Mr. Peal's suggestion appears to be a probable one, and is
supported by Mr. Worthington Smith's observations (Nature,
vol. li. p. 57). The spots may have been protective to the
animals during sleep, causing them lo look as if awake. The
reason that they do not occur in wild dogs may be that the
latter conceal themselves when sleeping, which the half-
domesticated animals were not able to do.

Alfred R. Wallace.

THE AGE OF THE EARTH.

SINCE physicists do not seem to be in complete
accord on the question of the time which has
elapsed since the earth first permanently crusted over,
it may perhaps be as well to investigate the evidence to
be obtained from a study of stratified deposits.

One of the first to raise a remonstrant voice against
the philosophers who demanded practically unlimited
time was Sir Archibald Geikie, whose original discussion
of the data known regarding the present working of
rivers gave us the fraction .jj'jjy as representing the
annual rate at which the Mississippi is lowering its
basin. The surprise with which this result was received
is now almost forgotten, in an unquestioning acceptance.
The question of the rate of deposition was next treated
by Dr. Haughton, in the year iSSo, with his usual mathe-
matical severity. Dr. Haughton, however, preferred to
take into consideration six other great rivers besides
the Mississippi, and thus obtained the fraction ,^.,q as
representing the average thickness of rock which is
annually worn away from the terrestrial surface by the
denudation of rivers. But the proportion of sea-bottom
to land surface is as 145 ; 52, so that if the suspended
sediment be spread evenly over the sea- floor, the average
rate of accumulation will be si-'i.-r of ^ foo' per annum.
The maximum thickness of the stratified series was
estimated by Dr. Haughton to be 177,000 feet, and thus
if the rate of deposition in the past was on the whole

534

NA TURE

[April 4, 1895

uniform and the same as that of the present, this
thickness of rock would have required a period of
1,526,750,000 years for its accumulation. Dr. Haughton
is not a uniformitarian, consequently he divided this
number by lo. Dr. Wallace next made what must be
considered a great step in advance, by pointing out that
the sediment which is carried into the sea is not de-
posited uniformly over the whole sea-floor, but, as the
Challenger dredgings clearly showed, along a compara-
tively narrow marginal tract. Instead, therefore, of
multiplying :;i^jjj (the yearly rate of denudation) by ,',-.,
he divided it by ,V (the proportion of the area of maxi-
mum deposition to the area of denudation), and thus
obtained 2S millions as the number of years required for
the accumulation of 177,000 feet of rock.

A further correction was next made by Mr. C. Davison,
who showed that the fraction ^un.cr 's obtained by an
error in arithmetic, and that the true value is .^^^u- In-
troducing this fraction into Mr. Wallace's calculation, we
obtain in round numbers 22 millions of years, a close
approximation to the result, deduced from physical
considerations, by Mr. Clarence King.

Of late years considerable additions have been made
to our knowledge of the thickness of the systems of
stratified rock, and 1 present the following table as
representing the maximum thickness of all known
formations down to the base of the Cambrian, a definite
horizon marked, as is well known by the occurrence of
fossil remains of most of the great subdivisions of the
Invertebrata : —

System.
Cambrian ...
Ordovician
Silurian
Devonian ...
Carboniferous
Permian ...
Trias
Jurassic
Cretaceous
Eocene
Oligocene
Miocene ...
Pliocene ...

Thickness in feet.

16,000

14,000

14,000

20,000

21,000

12,000

13,000

8,000

14,000

12,000

12 000

6,000

2,000

164,000

First appearance of

Fish

Amphibians

Reptiles

Mainmals

Eulheria

The total thickness is 164,000 feet, lying in a fairly
continuous series, and calculating by Mr. Wallace's
method, this leads to the conclusion that, in round
numbers, 21 millions of years have elapsed since the begin-
ning of Cambrian times. The truth of Mr. Wallace's
argument depends on the assumption that an area of
maximum deposition retains a constant position during
the existence of a geological system. This is no doubt
approximately the case, but so far as it is not, the devia-
tion from stability will render Mr. Wallace's estimate
deficient. On the other hand, as Mr. Wallace himself
recognised, the area of maximum deposition does not
extend uniformly round the coast line, but is concentrated,
if one may so speak, near the mouths of rivers : the
effect of taking this into account will far more than
compensate for any shifting of the area. It is unnecessary
to do more than point out that deposits, where they
attain their maximum thickness, are of a more or less
deltaic nature, and were probably deposited near the
mouth of large rivers, in seas more or less land-locked.
From investigations in which 1 am now engaged, 1 am
led to conclude that where systems attain their maximum
thickness, accumulation may have proceeded at the rate
of one foot in a century, or even more rapidly.

The question largely depends on the relative size of
areas of denudation and deposition : an objector to
my estimate may urge that accumulation at this rate
involves the existence of areas of denudation of much

NO. 1327, VOL. 51]

'arger dimensions than the map will find room for. It
is worth while to inquire into this, and a single ex.imple
will suffice. Let us consider the coal measures of the
British Isles. Suppose they cover, to the depth of
half a mile, a circular area 300 miles in radius, having its
centre somewhere over Anglesey, their volume will thus
be 141,372 cubic miles ; add to this 15,876 cubic miles for
the deposits of greater thickness occurring over the North
of England, and South Wales and Somersetshire. This
gives a total thickness of 157,248 cubic miles. But since
the maximum thickness is 12,000 feet, these will have
accumulated, according to our assumption of i foot in a
century, in 1,200,000 years. The coexistent area of de-
nudation affords ,_. |\yj7 of a foot of sediment per annum,
or oooooooS cubic mile per square mile yearly. In
1,200,000 years this will amount to nearly ,'„ cubic mile
per square mile ; and thus the 157,248 cubic miles of sedi-
ment Ml the coal measures will have required a land surface
1.572,480 square miles in area for their supply. This will
be represented by a circular area with a radius of 707'
miles, and that an area of land several times these dimen-
sions may have existed north and west of the British
Isles during carboniferous times, is an assertion which
most geologists will be prepared to defend.

So far as I can at present sec, the lapse of time since
the beginning of the Cambrian system is probably
less than seventeen millions of years, even when
computed on an assumption of uniformity, which to me
seems contradicted by the most salient facts of geology.
Whatever .additional time the calculations made on
physical data can afford us, may go to the account of Pre-
Cambrian deposits, of which at present we know too-
little to serve for an independent estimate.

No one can regard without satisfaction the introduction
into Lord Kelvin s argument of well-ascertained data as
regards the melting points and other properties of rocks.
Dr. Joly finds the melting point of basalt to be even
lower than that of diabase, viz. 815' C, a result ii»
accordance with that found by other investigators.
These facts, though of great assistance in supporting the
short chronologists of the earth's age, may prove-
embarrassing when the question of the physical state of
the interior of the earth is ready for reconsideration.
Dr. Joly finds the value of d/jilp for basalt to be
o'oo6, and for diabase, according to Carl Baru5, it is
0021 at 1 200' C. ; in either case the temperature gradient
gains on the melting point gradient rapidly enough to
show that, at no great distance beneath the surface of
the earth, the interior, if it consist of such rocks as
these, is in a state of liciuidity. Cleologists in general
would probably be glad to purchase an internal liquid
shell at a cost of several millions of years. WouUl not,
however, the admission of the existence of li(|ui<l shells
in the interior of the earth, deprive the mathematical
argument, as at present formulated, of all validity.'

W. J. SOI.LAS.

THE ANNIVERSARY OF THE CHEMICAL
SOCIETY.

"T^HE anniversary meeting of the Chemical Society
-•- was held at the .Society's rooms, on Wednesday
March 27, when the following officers and Council were
elected : —

President, Dr. A. O. Vernon Ilarcourt, ]•'. K.S. Vice-
Presidents (who have filled the office of President), .Sir F. A.
Abel, K.C.H., F.R.S., Dr. H. E. ArmstronK, F.R.S., Dr. A.
Crum Brown, F.K.S., W. Crookes, F.K.S., Dr. E. Frankland,
F.R.S., SirJ. II. Gilbert, F.R.S., Dr. I. II. Gladstone, F.R.S.,
Dr. n. Midler, F.R..S., VV. OdIinK," F.R.S., Dr. W. H.
Perkin, F.R.S., Lord Playf.iir, K.C.B., F.R.S., Sir II. K. I
Roscoe, F.R.S., Dr. W. J. Russell, F.R..S., and Dr. A. W. '
Williamson, F.R.S. Vice-Presidents Dr. E. Atkinson,'
Iloriice T. lirown, F.R.S., Prof. F. R. Japp, F.R.S., Lud*lg

April 4, 1895 J

NATURE

535

Mond, F.R.S.,C. O'SuUivan, F.R.S.,and Prof. W. C. Roberts-
Austen, C. B., F.R.S. Secretaries, J. Millar Thomson, and
Wyndham Dunstan, K. R.S. Foreign Secretary, Prof. Raphael
Meldola, F.R.S. Treasurer, Dr. T. E. Thorpe, F.R.S.
Council, 'Dr. P. Phillips Bedson, Bennett Hooper Brough,
Prof. Harold Dixon, F.lv.S., Dr. Bernard Dyer, R. J. Friswell,
OltoHehner, Dr. F. Stanley Kipping, Herbert McLeod, F.R.S.,
W. \. Shenstone. Ur. Thomas Stevenson, Dr. W. P. Wynne,
and Prof. Sydney Young, F. R. S.

Prof. Armstrong, F'.R.S., the retiring President, de-
livered his address, in which he gave an account of the
■work of the Society during the past year. The Faraday
Medal was presented to Lord Rayleigh for the distin-
guished services he has rendered to chemical science
through the discovery of argon. Lord Rayleigh re-
sponded in a lt.vi words, sharing the honour bestowed
on him with Prof. Ramsay. The President then called
on Prof. Ramsay, who laid before the Society an account
of the discovery of Helium in CiLveite, and on Mr.
Crookes, who described it spectroscopically. (These two
communications will be found in another column.) In
the evening the Fellows and their guests dined together
at the Hotel Metropole. Among those present were : —

Dr. H. E. Aimstrong, the Right Hon. Jas. Bryce, M.P.,
President of the Board of Trade ; the Right Hon. A. J. Balfour,
M.P., Sir Henry Roicoe, M.P., Mr. A. Vernon Harcouit, Lord
Rayleigh, Sir Waller Pndcaux, Clerk of the Goldsmiins' Com-
pany ;"Dr. W. J. Russell, Mr. T. F. Blackwell, Master of the
Salters' Company ; Prof. Odling, Sir Owen Roberts, Mr.
Carteighe, Mr. Layers Smith, Dr. W. H. Perkin, Prof. Thorpe,
Dr. J. H. Gladstone, Mr. W. Crookes. Dr. Stevenson, Mr. C.
K. Groves, Prof. McLeod, Prof. Percy Frankland, Prof. Riicker,
Prof. Dunstan, Dr. Atkinson, Prof. Ramsay, Prof. Emerson
Reynolds, Prof. Dewar, .Sir H. Gilbert, Prof. Smithells, Prof.
Tilden, Dr. Wynne, Mr. Alex. .Siemens, Prof. Thomson, Mr.
Thisellon-Dyer, Dr. Hugo Miiller, Mr. Norman Lockyer, Sir
P. Magnus, Prof. Meldola, Dr. W. PL Symons.

A full report of the speeches made at the dinner
appeared in the Times of the following day, and we are
indebted to it for the following extracts : —

In proposing the toast of the Houses of Parliament, the
President, Dr. H. E. Armstrong, remarked with reference to
argon, that the discovery which Lord Rayleigh and Prof. Ram-
say had made was not a chance discovery, but was the out-
come of twelve years of hard work on the part of Lord Rayleigh
in pursuit of the fourth decimal. The interest in the newly-
discovered argon would undoubtedly be an abiding one, and it
was believed that its development would be one of the most
extraordinary di.-coveries that had been made in our time. He
also referred to the discovery of Helium by Mr. Norman
Lockyer, and its recent identification by Prof. Ramsay and
Mr. Crookes.

Mr. Bryce, in responding to the toast, said : Physical science,
and particularly chemical science, very frequently came in con-
tact with the work of the administrators of the Government, and
hardly a day passed by when they were not connected in some
way with electricity or chemistry. He had been greatly im-
pressed by the progress made in the quantity of science teach-
ing, which had in some places almost ousted the literary side of
teaching. In spite of that large quantity of science teaching,
however, the Universities had not yet provided adequate means
for the preparation of science teaching : and although there
were a great many men teaching scientiBc knowledge and
teaching it well, enough had not been done to give them a
■systematic training and to make them not only scientitic men,
but skilful, finished, and experienced teachers of science as a
special branch of instruction. A good deal remained to be
■done in that way.

Mr. Bnlfour made the speech of the evening in proposing
" Prosperity to the Chemical Society." In the course of his
remarks, ho said : In the last speech to which we listened with
so much pleasure, the President of the Board of Trade reminded
us that his department — one of the most important departments
in the Government — was brought face to face and in the closest
relation to science almost every day in connection with one or
other of the great practical questions with which it has to deal.
Undoubtedly that is so, but I think he will probably agree with
«ne when 1 say that we politicians — he and I who are engaged

in the work of everyday political conflict — cannot boast that we
or those whom we represent are in the position of using science
as the handmaid of great national purposes, or that we have
the power to turn it and direct its great forces whither we will.
For my own part, though the last thing I wish to do is to sug-
gest that the work of practical politicians is o'her than a work
which takes the highest qualities of a man, still I have to admit,
on looking back on the history of civilisation, that if we want
to isolate the causes which, more than any other, conduce to the
movements of great civilised societies, you must not look to the
politicians of the hour on whom, it may be, all eyes are fixed ; you
must look to those who, often unknown by the multitude, whose
work, it may be, is never properly realised by the men of their
country till after they are dead — you must look on I hem and
on their labours to find the great sources of social movements.
It is to those who, very often with no special practical object in
view, casting their eyes upon no other object than the abstract
pure truth which it is their desire to elucidate, penetrate further
and further into the secrets of nature and provide the practical
man with the material upon which he works — these are the men
to whom, if you analyse the social forces to their ultimate units,
we owe most, and to produce such men, and to honour such
men, and to educate such men, does the Society, whose health
I am now proposing, devote its best energies. I do not think,
so far as I am acquainted with scientific history, that English-
men need fear that they have been behind the rest of the world
in evolving those root ideas which are the sources of great
discoveries, which are themselves great discoveries, and
which are, too, the sources and roots of other great
discoveries. It may be, however, that though, as a nation,
we have been as productive as other nations — I put it modestly
— in the men of genius who have made these fundamental dis-
coveries, we have not, as a nation — and I do not think we
have — sufficienlly realised how great a bearing theory in these
modern days must necessarily have upon practice if we
are to keep pace with the rest of the world. We have produced
great theorists — none greater. We have produced men of great
practical genius — none greater. I am not sure, however, that
at this moment we are not behind one at least of the great
nations of the continent, perhaps more than one, in the art of
combining theory and practice — in the art of so welding to-
gether in a great organic and self-supporting whole the man of
genius, who at one end of the scale discovers a new law of
nature, and the man of practice, on the other hand, whose busi-
ness it is to turn these discoveries to account. I do not venture
upon a subject upon which, after all, I am not wholly com-
l^etent, and I will not develop this subject at greater length ;
but I should like to do what I can lo dispel the prejudice which
certainly exists at this moment in certain influential quarters
against technical education properly understood. Technical
education properly understood, suffers greatly under technical
education improperly understood, and there is so much nonsense
talked upon this subject, there is so much money uselessly spent,
there are so many things taught to persons who do not want to
learn them, and which, if they did want to learn them,
they could by no possibility turn to practical account,
that it is no matter of astonishment that some persons
arc disposed to say that "technical education is only the
last bit of political humbug, the last new scheme for turn-
ing out a brand new society ; it is worthless in itself, and not
only is it worthless, but it is exceedingly expensive." While I
think that those who object to technical education have their
justification, it yet remains true that if you include, as you ought
to include, within the term technical education, the really
scientific instruction which would turn scientific discoveries to
practical account — if that is what you mean, or what you ought
to mean, by technical instruction, then there is nothing of which
England has at this moment any greater need, and there is
nothing which, if she, in her folly, determines to neglect it,
will more conduce to the success of her rivals in the markets
of the world, and to her inevitable abdication of the position of
commercial supremacy which she has hitherto held. I do not
deny that manufactures and commerce have received an immense
amount of gain from theoretical investigations, and, as every-
body will admit who has even the most cursory acquaintance
with, let us say, the history of discoveries in electricity and
magnetising power, science has been the means of great gain
through industrial development. While both these things are
true, I am the last person to deny that it is a poor end, a poor
object for a man of science to look forward to of merely making

NO. 1327, VOL. 51]

536

NATURE

[April 4, 1895

money for himself and other people. After all, while the effect
of science on the world is aImo;t incalculable, that effect can
only be gained in the future, a? it has only been gained in the
past, by men of science pursuing knowledge for the sake o(
knowledge and for the sake of knowledge alone ; and if I
thought that by anything that had droppe i from me to-night I
had given ground for the idea that I looked on science from what
is commonly called a strictly utilitarian point, that I measured
its triumphs by the, number of successful companies » hich it
had succeeded in starting, or by the amount of dividends which
it gave to capitalists, or even by the amount of additional
comfort which it gave to the masses of population, I should
greatly understate mythought;but I know that this great Society,
while it has in view these useful objects, still puts first of all
the pursuit of truth as its object and as the cause to which
every man of science pays his devotion. Truth, not profit, must
necessarily be the motto of every body of scientific men who
desire to be remembered by posterity for their discoverie?.
These things can be done only from a disinterested motive, and
it is because I believe that societies like the great Society I am
addressing do more than any other organisation to attain that
great object, because I think they bring together men engaged
in congenial pursuits, because the stimulus of minds brought
close to other minds with honourable motives, and the
honourable rivalry of men engaged in the same great task, must
lead to an enormous expansion of our knowledge of the secrets
of nature, that I, as an outsider, not belonging to your body,
but in the name of the public for which I venture to speak,
wish you all success and all prosperity.

The President briefly responded to the toast.

Mr. Veinon Harcourt proposed " Learned Societies," coupled
with the name of Lord Rayleigh, who briefly responded.

Sir Henry Roscoe proposed " The Visitors," and Sir Owen
Roberts and Prof. Rucker responded.

Dr. W.J. Russell proposed "The President," who concluded
with the roast of "The Secretaries," coupled with the name
of Prof. Thomson.

SIR HENR Y CRES WICKE RA WLINSON, BA R T.

TLJENRY CRESVVICKE RAWLINSON was de-
•l -^ scendedfrom the family of Rawlinsons who, in the
last century, settled down at Chadlington, in the county
of 0.xford ; he was born April ii, iSio, and in 1S62 he
married Louisa Caroline Harcourt, daughter of Henry
Seymour, of Knoyle, Wilts, and he died on March 5
last. At the early age of seventeen he went out as cadet
to India, and in a very short time made himself an excel-
lent Persian scholar ; in 1833 he was sent to Persia, his
fine command of the language of that country, no doubt,
influencing his selection by ''John Company." For six
years he served diligently, and filled many military posts
in the great cities of Persia, and he succeeded in infusing
something nearly akin to order in the forces of the " King
of Kings." In 1839 the relations between England and
Persia became "strained," and Rawlinson left the
country for Afghanistan ; in 1840 he was appointed
Political Agent of the Indian Government in Kandahar,
a post which he held until 1S42. During these years he
wielded the sword as often as the pen, and his courage
and personal bravery in the field made him a terrible
opponent of the wily Afghan. In 1S44 he was sent to
Bagdad as H.B.M.'s Consul for Turkish Arabia, and in
1851 he was made Consul-General, the importance of
Bagdad being, thanks to Kawlinson's labours, fully recog-
nised. In 1855 he was made Crown Director of the
East India Company, and in 1S56 he was promoted to
the dignity of K.C.B. ; two years later he was elected
Member of the India Council, and in 1859 he was sent
to Teheran as Minister Plenipotentiary. He represented
in Parliament for a short time (1865-1868) the borough
of Frome, but a Member's life offered no attractions to
him.

The above brief statement of facts will indicate suffi-
ciently the abilities of Rawlinson, who was a man equally
able as a statesman, diplomat, and soldier ; but there is

NO. 1327, VOL 51]

yet another side of him of which nothing has been said,
and it is that of the scholar. Before Rawlinson had
been five years in India, he had read the greater part of
the literature of Persia, and he was even at that time
(1S32) a skilled and lluent talker in Persian ; long pas-
sages from the finest poets he had learned by heart, and
his conversations were so full of extracts from them, that
a native once described his talk as "a garden of pearls
in metre." From modern Persian to the ancient language
is, relatively, but a step, and when Rawlinson found
himself in Persia in 1S33, he turned his mind to the study
of the remains of the kings who had cut their records in
the rocks in the cuneiform characters. So far back as
1835, he copied the tablets at Hamad.in, and without the
help of books, or even any knowledge of the alphabet
worked out by Grotefend in 1S02, by making the same
guesses as Grotefend, he identified correctly the names
of Hystaspes, Darius, and Xer.xes. In 1S36 he collated
the first paragraphs of the great Behistun inscription
with the tablets at Elwend,and identified the old Persian
forms of the names Arsames, Ariaramnes, Teispes,
Achaemenes, and Persia; by this time he had made an
alphabet of eighteen characters. Early in 1S37 he had
copied all the other paragraphs of the Behistun inscrip-
tion, and in the winter of that year he sent to the Royal
Asiatic Society his translation of the two first paragraphs
which recorded the genealogy and titles of Darius Hys-
taspes. Without any desire to belittle the work of other
investigators, we must say that these would have been
inexplicable if the systems of transliteration followed by
(jrotefend and Saint Martin had been employed, and
whatever else may be theirs, Kawlinson's discovery at
this period of the phonetic values //;, /', iii and n is
beyond all doubt. About this time he decided that the
translation of the Persian cuneiform texts could only be
eftected by a knowledge of /.end, and he set to work to
master the contents of the work of .\nquetil du Perron
and M. Burnouf's commentary on the Vacua, which
was, however, not in his hands until 1S3S ; he obtained
some assistance, too, from a priest of Yezd, who trans-
lated for him some /end MSS. In 1S38 Rawlinson dis-
covered the phonetic values of //, 7i', /', ■;', //; and ///. and
in 1839 he had practically settled the alphabet, which in
all essential points agreed with that of Lassen, published
in his .llt-ficrsisclten Kdlinschriftcn. Here must be
noted the fact that Rawlinson never contested the
priority of alphabetical discovery with Lassen, even
though there is abundant proof that all he owed
to Lassen was a single phonetic value ; but what he
did claim, and claim rightly, was the credit of having
translated literally and grammatically two hundred lines
of cuneiform writing which contained historical state-
ments of the greatest value, /cr t lie first time, as early as
1S39. In this year, while he was putting the final touches
to his work, political necessity caused him to be sent from
Persia to .\fghanistan, and his studies were so much
interrupted during the next five years, that he was unable
to publish the result of his labours until 1847^

Aleanwhile the nunind of Kouyunjik, which marks the
site of the palaces of ancient Nineveh, was being ex-
plored by Mr. l.ayard, and the mound of Khorsabad,
some few miles off, had begun to yield splendid results
to its talented excavator, .M. Botta. That Kouyunjik
formed part of old .\ineveh was always well known, and
so far back as 1820 Mr. Rich picked up three fragments
of clay tablets inscribed in cuneiform writing. As soon
as Rawlinson could obtain copies of the inscriptions dug
out by Mr. Layard he devoted himself to the study of
them, and the practical outcome of these labours were
his publications : — "A Commentary on the Cuneiform
Inscriptions of Babylonia and Assyria ; including
readings of the inscription on the Nimrud Obelisk, and

' In ihc tenth volume of the J^Hiniat of the Royal AsiatU Siiciit)-
(London, 1847.)

April 4, 1895]

NATURE

537

a brief notice of the ancient kings -of Nineveh and
Babylon," London, 1850; and "Outline of the History
of Assyria," London, 1852; and "Notes on the Early
History of Babylonia," 1854. He had also in 1850 and
1 85 1 revised the "Inscriptions in the Cuneiform Character
from Assyrian Monuments,'' which Mr. Layard published
in 1851. Curiously enough, though Rawlinson's translation
of the Behistun inscription was accepted generally, there
were many, and Sir G. C. Lewis was among them, who
stated unhesitatingly that the cuneiform inscriptions had
not yet been accurately deciphered, and we owe it to
Mr. Fox Talbot that this view was proved to be erroneous.
Rawlinson had undertaken to publish a series of cuneiform
texts with English translations of the same for the
Trustees of the British Museum, and Talbot, having
obtained a set of the plates of the text of the great
Tiglath Pileser inscription, began to work at an in-
dependent translation which, when finished, he sent in
a sealed packet to the Council of the Royal Asiatic
Society, pointing out that if his own translation and that
of Rawlinson, when it appeared, should agree, a strong
proof of the accuracy of Rawlinson's system would be
established. The Council appointed a Committee con-
sisting of Dean Milman, Whewell, Gardner Wilkinson,
Grote, Cureton, and Prof. Wilson as examiners, and they
asked Rawlinson, Oppert and Hincks to send in versions
of the same inscription by a certain date. I'albot's
arrived first, Rawlinson's next, Hincks's next, and Oppert's
next ; the last two scholars could not, however, translate
all the inscription for want of time. The four independent
translations' were carefully examined, and it was found
that they agreed as to general sense in a marvellous
manner, and the Committee rightly judged that the
decipherment of the cuneiform inscriptions was a fait
accompli; Rawlinson, however, translated the whole
text, while his three competitors left passages here and
there unrendered.

In the matter of publication, Rawlinson's greatest
work was undoubtedly the " Cuneiform Inscriptions
of Western Asia" in five vols, folio, which he
prepared for the Trustees of the British Museum ; here
he supplied material for generations of workers, and gave
the proofs of his knowledge and ability in cuneiform
matters, which have justly earned for him the title of
" Father of Assyriology." Between the years 1858 and
1875 he largely assisted his brother Prof. Rawlinson
in his works on Oriental history, and a large share
of whatever credit attaches to them is due to him.
His last published translation was that of the cylinder
of Cyrus, which recorded his conquest of Babylon ;
it appeared in the Journal of tlic Royal Asiatic
Society, new series, vol. xii. (1S80; p. 70. As was
to be expected, honours were showered upon Raw-
linson from all parts of the civilised world. He was
elected to a Trusteeship of the British Museum — a much
coveted honour — in 1876; Oxford, Cambridge, and Edin-
burgh gave him honorary degrees ; Prussia awarded him
the " Ordre pour le Mcrite " ; and the Academies of other
countries elected him to Memberships. In summing up
his labours, it is hard to say whether he did most for
cuneiform scholarship, or to advance the interests and
empire of Her Britannic Majesty in the East. Smali-
minded men, wishing to lessen Rawlinson's merits, have
harped upon the fact that Lassen made his alphabet
before Rawlinson ; but this he freely admitted, only say-
ing in reply that he never saw it until 1839. That Raw-
linson was the first European who translated cuneiform
inscriptions, is beyond all doubt, and from first to last,
j>. from 1835 to 1895, he exercised a wise and beneficent
influence over cuneiform studies which cannot be over-
rated. His position in Persia gave him unrivalled
opportunities, which he used to the best of his ability,

1 See Rawlinson, "Inscription of Tiglath-Pilescr I., King o Assyria,
about 1150 B.C." (London, 1857.)

NO. 1327, VOL. 51]

and as Consul of Bagdad from 184+ to 1855, his strong
but silent power was freely exerted on behalf of Mr.
Layard while carrying on his work at Kouyunjik ; be-
yond all doubt is it the fact that he has done more for
cuneiform research and excavation than any other man
living or dead. It must never be forgotten, too, that he was
the only early excavator who had fully qualified himself
to understand his work, and of them all he was the only
one who could read cuneiform. He was a fine example
of the English soldier, now only too rare, for to the
bravery of the warrior he added the courtesy of the
diplomat, and a wide knowledge of Oriental countries,
languages, and history ; his modesty was as great as his
learning was deep. His ready wit and honest straight-
forwardness made him a favourite at every Oriental
Court, and helped greatly to bring his plans to a suc-
cessful issue ; and his fearless bearing and manly love
of warlike exercises attracted to him the admiration
of the Indian and Persian soldiers who came in
contact with him. His tolerance led men, both in
the East and in the West, to confide in him, while
his natural good-heartedness often made them like
him as much as they trusted him. Other English-
men have left behind them in the East fame for a certain
exploit, or renown as great horsemen, cSrc, but no man
was more feared and liked throughout the East than
Henry Creswicke Rawlinson. He was a thorough
Englishman, and with him English interests were para-
mount everywhere ; he never forgot, too, in spite of his
gracious bearing to all, that he was a trusted servant of
the " Right Honourable John Company Sahib Bahadur."
Wherever he went he impressed his personality in a
marvellous degree, and an idea of the reputation which
he left behind him in Bagdad may be gained from the
remark which an old native of that city made to a British
merchant some years ago. " Sahib, in the days of
Rawlinson Sahib, may God lengthen his life, if you had
put an English hat on the head of a dog and sent hint
through the bazaar, the Turks would have made way for
him and bowed to him on the right and left as he passed,
and now they spit on us as they pass us."

NOTES.

We are glad to learn that Prof. Huxley is now rapidly
recovering from his recent attack of influenza.

Rei'EREN'CE was made last week to the activity and
great development of the Brooklyn Institute of Arts and
Sciences. Among the most successful of its recent en-
terprises must be counted the establishment of a summer
school of biology by the sea. The first session was held
in July and August 1S90, at Cold Spring Harbour, on
the north shore of Long Island, in a building lent by the
New York Fish Commissioners. The school annually in-
creased in size and importance, and a specially designed
laboratory, capable of accommodating fifty students, was last
year opened for work in the same locality. The laboratory
is well arranged for the purposes of lectures and practical
instruction, and possesses private laboratories for investigators,
a library, aquaria with running water, both salt and fresh, boats,
microscopes — indeed everythiog needed to make profitable a
Gjmmer at the sea-shore. It is impossible to over-estimate the
advanl.iges which marine laboratories afford for the purpose of
biological instruction ; and America may be congratulated
upon the successful inauguration of an institution specially
adapted to subserve this important end.

We drew attention a short time ago (Nature, vol. xlix.
p. 597) to the fact that the late Sir W. Macleay had willed to
his executors the sum of ^^12,000, for the foundation of a chair
of Bacteriology in the Sydney University. The terms of the

00

8

NA TURE

[April 4, 1S95

tx quest provided for a six months' course on the subject, to be
binding on every student before being admitted to a science or
medical degree at the University. Pending the inability of the
Senate lo accept, within a month after notice of the legacy, the
conditions contained in a memorandum annexed to the will, the
legacy was to be void, and the sum given over to the Linnean
Society of New South Wales, for the endowment of research in
bacteriology. On receiving the money, the senators, the majority
of whom are lawyers, have sought a judicial interpretation of
the words "six months' course, ' and have secured the hand-
some endowment to themselves, on the ruling of Court, for
-disposal on their own terms. What they will do with it re-
mains to be seen. Sir W. Macleay had been a member of the
Senate, and his impiession of its conduct may be gauged from
the fact that in bequeathing this very legacy he took especiril
pains to protect his executors against that which he termed " its
very uncertain views." In this he has failed! " Sharp prac-
tice "may be a conventional, but it is hardly a befitting term for
the behaviour of the Senate, which thus expresses the gratitude
of a colony for the devotion of a life and foitune to the advance-
ment of science and scientific education.

We understand that the Macleay memorial volume is selling
very slowly. Its promoters are considerably to the bad on the
undertaking.

Dr. Doberck would be glad if astronomers who notice
shooting stars having radiants south of the equator, will send
their observations for discussion to the Hong Kong Observatory,
■where some attention is being paid to southern shooting stars.

General Sir George Chesnev, to whom belongs the
credit of originating and organising the Royal Indian
Engineering College at Coopers Hill, died on Sunday.

Prof. Ludwio Schlafli, the well-known Swiss mathe-
matician, has just died at Berne, at the age of eighty. In 1853
he «as appointed professor of mathematics at the University of
Berne, where he first acted a.5 privatJccent, but some time ago
he gave up his post on account of his advanced years.

Messrs. Sothebv, Wilki.nson, and Hodge will include
the original autograph manuscript of Gilbert White's " Natural
History and Antiquities of Selbotne " in their sale commencing
Apiil 22. Several passages in the manuscript have not been
published, and the whole has never passed out of the possession
of the lineal descendants of the author.

The Geologists' Association have arranged an excursion to
the Tertiary Beds of the Isle of Wight, during ICaster, under
the direction of Mr. R. S. Herries and Mr. H. W. Monckton.
The party will leave London next Thursday, and will return
on the following Tuesday.

The Liverpool Marine Biology Committee have appointed
Mr. J. C. Sumner, from the Biological Laboratory of the Royal
College of Science, South Kensington, as Curator of the Port
Erin Biological station.

Dr. Jentink, of Leyden, hasrccenllydrawn attention lo the
scantiness of trustworthy evidence concerning the distribution of
the two species of Rhinoceros which inhabit the Malay archi-
pelago. It is sometimes stated that l>oth species (A". siiiiKilrensis
and K. sondaitus) are 10 be found in Borneo, Sumatra, and
Java ; but it appears that nothing can be maintained with
absolute certainty at present, except that /i". sondaictis inhabits
Java, and /'. iunalrcmii both Sumatra and Borneo. It is
clearly desirable that any authentic information bearing upon
this point should be brought to light, if yet unpublished.

The Biological and Microscopical Section of the .\cademyof
Natural Sciences of Philadelphia have just sustained a severe

NO. 1327. VOL. 51]

loss by the sudden death of Dr. George A. Rex. Dr. Rex was
the highest authority an the Myxomycetes in the United States.
He was the author of numerous species, which, owing to his
extreme conservatism, will doubtless continue to bear his name.
Many forms, new to him, remained in his collection unnamed
for years, and were only published when he had thoroughly
convinced himself that they were really new to science.
Although he was interested principally in the Myxomycetes,
he was an earnest student of the lower orders of fungi, and an
ardent admirer of everything beautiful in microscopic nature.

We have also to record the deaths of a number of
other scientific workers in the United States. Dr. Darwin
G. Eaton died in the evening of March 17, aged seventy-
two. He was prominent as an instructor in the Packer
Institute and in the Long Island College Hospital. His
works belong chiefly to chemistry and astronomy. He
was twice a member of Government parties to observe
eclipses of the sun. Dr. P. H. Van der Weyde died a few hours
later, on the iSth ult. He was born at Wymeguen, Holland,
in 1S13, and removed to New Vork in 1S49. He taught in the
University of the City of New York, at Cooper Union, and
Girard College. Dr. Henry Coppee, acting president of
Lehigh University, "died March 20, at Bethlehem, Pa., aged
seventy-five years. He was elected Regent of the Smithsonian
Institution in 1874. Mr. Isaac Sprague, well known as a
botanist and artist, and illustrator of botanical works, died at
Wellesley Mills, Mass., March 13.

We notice the announcement of the death of Mr. .\. Ci.
More, who for many years exercised an influence of a special
kind on the zoologists and botanists of Ireland as an authority
to whom they implicitly referred questions on the sul>ject of the
determination of the species of Irish birds and Irish plants.
Under the modest title of " Contributions towards a Cybele
Ilibernica," in conjunction with the late Dr. David Moore, he
published in 1S66 an excellent account of the geographical
distribution of plants in Ireland. Another good piece of work
by him was his list of Irish birds, published in the year 1885,
in connection with the collection in the Dublin Science and Art
Museum, and in 1887 he published an excellent guide to the
Natural History Department of the Museum. He succeeded
Dr. Catte as Curator of that department, but illness compelled
him to retire in 18S7, after twenty years' service.

The annual banquet of the Institution of Civil Engineers
took place on Wednesday, March 27, a distinguished company
being present. Sir Robert Rawlinson, K.C.H. (the President)
occupied the chair, and among the guests were the Duke of
Cambridge, the Duke of Teck, the American .-Vmbassador, the
Marquis of Salisbury, Sir John Fowler, Sir Frederick Brani-
well. Sir Redvers Buller, Mr. C. T. Ritchie, Sir F. A. Abel,
Sir George Stokes, Sir Courten.-iy Boyle, Sir John Donnelly, ■
Mr. Henry Kimber, M.P. (Master of the Merchant Taylort'
Company), Dr. Anderson, Sir B. Baker, Mr. C. Barry, Prof.
Forbes, Dr. Frankland, Mr. Hawksley, Dr. Kennedy, Sir G. 1
L. Molesworth, Mr. Preece, Mr. Rennie, Prof. Robetts-AusteD,
Sir David Salomons, Prof. Unwin, Mr. Walmislcy, and Mr.
Yarrow. The Marquis of Salisbury, in proposing the toast of
"The Institution of Civil Engineers," dwelt upon the system ol 1
sanitary military reform set on foot by Sir Robert RawlinsoD, 1
and which has had such bencfical results. He continued:—
The system has yet some advance to make, and I hope some
day the civil engineers, if the military engineers do not do it,
will lemove the reproach of typhoid fever from our barracks.
Hut an enormous distance has been traversed by the genius o(
civil engineers, and by none more than by the President who
occupies your chair ; and I think it has reacted on civil society.
We never really took in hand the sanitation of our civil popii-

April 4, 1895]

NA TURE

539

lation until we had been taught by necessity, by the evils
attacking our military forces, and the remedies that were
adopted, to confront those evils ; and the result of the last
forty years of sanitary exertion on the part of civil engineers, is
one of the most splendid triumphs in the history of any pro-
fession which has adorned this country. You have done what
many a continental nation wishes it could imitate you in doing.
You have driven cholera from your shores. It can no longer
make any impression upon us, and year by year the health of
the population grows, the sanitary reforms increase, and you
have converted all those who once doubted to believe in the
sanitary character of the maxims which you inculcate and the
methods which you propose.

Major Cardew's report on the circumstances attending the
accidents which have lately occurred in London, in connection
with electric light main>, has been published in a Parliamentary
paper. The accidents were of two kinds — those due to severe
electric shocks caused by strong electrification of the surface of
the ground, and those resulting from explosions in the street
boxes through which the electric light mains run. In the City
cases investigated by Major Cardew, the immediate causes of
the accidents were : the breaking down of the insulation of a
high pressure main in a street box, causing the formation of a
powerful electric arc between the outer conductor of ttiis main
and the end of an iron pipe, forming a conduit for the mains,
which projected into this box, and the consequent charging of
this pipe to a dangerous extent ; and the presence of gas in the
Electric Light Company's pipes and street boxes to an amount
which formed a highly explosive mixture afterwards fired by the
electric arc. In the case of explosions in the St. Pancras dis-
trict, it was suggested that the explosive gas was derived from
the sewers, and also that it was hydrogen generated by electro-
lytic action. Major Cardew could find, however, no trace of
such action, and, after careful consideration of the evidence and
his own investigations, he concludes that the explosions were
caused by the firing of a mixture of coal-gas and air by an
electric spark. No time should, therefore, be lost in removing
these two existing causes of danger, namely, the possibility of
an accumulation of coal-gas in the conduits and that of the
occurrence of an electric spark at the mains, whether the mains
be insulated or of bare copper strip, such as is used by the St.
Pancras Vestry. This Vestry has previously had their attention
drawn to the necessity of efficient ventilation, but have lailed
to remedy the defects. The inquiry elicited the fact that there
are only eleven ventilating pipes and three ventilating covers to
street boxes for a total length of six and a half miles of conduit,
a proportion quite inadequate for the immediate escape of gas
from the conduits. Major Cardew recommends that accumula-
tion of gas should be prevented by thorough ventilation, by
making the sides and bottoms of street boxes impervious to
gas, and by filling up the boxes as far as practicable with in-
combustible material. It is to be hoped that the Board of
Trade will see that his recommendations on this and other
sources of danger are acted upon.

The New York Academy of .Sciences, on Wednesday,
March 13, repeated the experiment, begun last year, of giving
an annual exhibition, with very gratifying results. Numerous
scientific instruments were exhibited ; the apparatus which
excited most general interest being one for testing and photo-
graphing the voice.

A MEKTING of the Institution of Mechanical Engineers will
be held on Wednesday evening, April 24, and Friday evening,
April 26, at 25 Great George Street, Westminster. The discussion
will be resumed, on the Wednesday evening, upon the governing
of steam engines by throttling and by variable expansion, by

NO. 1327, VOL. 51]

Captain H. Riall Sankey. The third report to the Alloys Research
Committee will be presented by Prof. W. C. Roberts- Austen,
C.B., F.R.S., and also appendices to it on the elimination of
impurities during the process of making "best selected'
copper, by Mr. Allan Gibb, and on the pyrometric examinatioi>
of the alloys of copper and tin, by Mr. .\lfred Stansfield. The
anniversary dinner will take place on Thursday evening,
April 25.

The New York signal service office, a branch of the United
States weather bureau, has just been removed from the Equit-
able building. No. 120 Broadway, which has been its head-
quarters for twenty-four years, to the new Manhattan Life Insur-
ance Company's building. No. 66 Broadway, which is now one
of the highest buildings in the world. The bureau will occupy
the twenty-first, twenty-second, and twenty-third stories in the
tower, and the observations will be made at a height of 356-
feet above the street, or 3S0 feet above tide water. The old
quarters were only 1S5 feet from the street. The equipment
will all be new, and will include electric signal lights, which
can be seen as far as Asbury Park and Fire Island. When the
weather bureau was established in 1870, it occupied the top
floor of a building in Wall Street for a few months. On the
completion of the Equitable building, that was selected as then
the highest in the city, but the rapid growth of tall ofiice build-
ings all around has made it undesirable as an observing
station. Even the present lofty quarters will soon be over-
topped by the building of the American Surety Company,
twenty-seven stories high, on the corner of Broadway and Pine
Streets, between the Equitable and the Manhattan buildings.

Extensive geological researches have been made by Russian
mining officers, as well as by professors of the Tomsk univer-
sity, in connection with the Siberian railway, which, as is
known, has already been completed as far as the Irtysh,
opposite Omsk. Numerous layers of coal have been found in
the basin of the Irtysh, but none of then have any industrial
value. Rich palasontological collections, which very well
characterise the age of the coal-bearing deposits of the Kirghiz
Steppe, have, however, been made out at Bez-tyub?. The best
coal was found at Kuu-cheku, 40 miles from Karaganda,,
but it is too far from the railway (375 miles) to have an
immediate practicil value. The great difficulty which the
builders of the railway have to contend with is the total
absence of building stone in these lowlands, covered with clays
and sands. Thus, for the building of the brid^je over the
Irtysh, near Omsk, new carlies had to be opened higher up the
river, but the cost of extraction and transport was so great
that most of the stone required for the bridge is brought by
rail from Chelyabinsk, a distance of nearly 50J miles.

The Society of Naturalists at the St. Petersburg University
which celebrated last year its twenty-fifth anniversary, has
issued an excellent volume containing a review of its five-
and-twenty years' activity. Each branch (zoology, physiology,
botany, and geology) is treated by a specialist, and the reviews
show at a glance what has been done in each of these
divisions of science ; while the work of botanical, zoological,
&c., exploration of the Russian Empire which has been
accomplished by members of the Society, is represented on
two maps. It is sufficient to say that the White Sea, the
Caspian Sea, the Aral Caspian and the Altai expeditions,
which have so often been mentioned in these columns, the
Crimea and the Neva Permanent Committees, and the
Solovetsky biological stations, are the work of the Society. The
volume is adorned by a good portrait of the late Prof. K. Th.
Kessler, the founder of the Congresses of the Russian Naturalist,
and Doctors, and also of the Societies of Naturalists at all the

540

NA TURE

[April 4, 1895

Russian Universilies. The Society, which began twenty-five
years ago with 74 members only, has now 374 active and 25
honorary members.

The Karan Society of Naturalists at the Kazan University,
which was founded in 1S69, has also issued a similar anniversary
volume, in which the review of work done in botany is especially
valuable, as it has been written on the above plan. The volume
contains also an index of all papers published in the twenty-
seven volumes of its Bulletin and Memoirs, the titles of the
papers being given both in Russian and German.

An old estimate of the frequency of earthquakes was that no
a day passed without a shock being felt somewhere on the
earth. In a new determination (Comples renJus, vol. cxx. pp.
577-579), M. de Montessus de Ballore obtains a much higher
figure. Dividing all the registers we possess into historical,
seismologica and seismographical, and assuming the latter to
be perfect, he finds, by comparing the different classes for the
same region, that in the first 96'24 per cent., and in the second
84 '48 per cent., of the total number of shocks escape record.
In a group of well-studied earthquake districts, with a combined
area of 11,691,000 sq. km., the average yearly numbers of
shocks for the three classes are 341 '35. 878'57. ^id 222224
respectively. Hence, multiplying by the proper factors for the
first two classes, it would appear that the total number of shocks
actually occurring in the above area must be estimated at 16,957
a year, or one in every half-hour.

In several papers of great interest {Atii della K. Ace. dei
Fisiocrilici, Siena, vol. v., 1894), Prof. G. Vicentini describes
his new seismometrograph erected at Siena, and the seismic
record obtained with it from February to July, 1894. The in
strument consists of a heavy pendulum, ij m. in length and
50 kg. in mass, the base of which is connected with one end of
a very light vertical magnifying lever. The other end of this
lever is connected with the ends of two light horizontal levers
placed at right angles to one another. These magnify the
original movement of the ground seventy times, and trace fine
lines on two strips of smoked paper moving at the rate of
2 mm. a minute. With this arrangement the heavy mass, it is
found, remains stationary during vibrations of the ground, and
the trace ceases simultaneously with the removal of the dis-
turbing cause. For seismic purposes, the instrument possesses
several advantages, especially the small cost of working and
the rapid movement of the paper bands. In the plates accom-
panying the papers, copies are given of the traces produced by
passing carriages, by strong gusts of wind, and by several earth-
quakes.lhe most beautiful being those of the Japanese earthquake
of March 22, the Greek earthquake of April 27, and the Con-
stantinople earthquake of July 10.

Sorgeon-Captain R. H. Elliot, of the Indian Medical
-Service, h.-is recently reinvestigated the value of strychnine as
an antidote against snake poison in the most thorough manner.
He experimented chiefly with cobra poison, but also with the
venom of Kujicll's viper and the krait, using frogs, lizards,
ducks, fowls, hares, guinea-pigs, dogs, goats, pigs, and monkeys
as test animals. He confirms the results of Drs. D. D.
Cunningham and A. A. Kanthack, that strychnine is not an
antidote against snake poison.

That the German Cholera Commission has worked most
energetically is shown by the voluminous documents now
appearing in the Arlieilenaiiiiltm Kaiierlichen Gesiindheilsamle.
A detailed inquiry has been held into all the various outbreaks
of cholera which occurred in Germany between the latter part
of the yean 1892 and 1893, respectively, and the mass of
NO. 1327, VOL. 51]

minute incidents thus collected have been brought to-
gether, and cover considerably over 600 quarto pages. The
Hamburg inquiry not unnaturally occupies the largest volume,
and is extensively illustrated with diagrams, &c. The Commis-
mission has succeeded in producing a most important and
valuable contribution to the study of epidemiology, and their
labours on cholera must long be regarded ES the standard work
on the subject. We only wisli that influenza, which is now far
more conslanily with us, and claims such an increasing number
of victims, might be subjected to the same crucial inquiry ;
possibly then, as in the case of the later outbreaks of cholera in
Germany, we might be in a position to take some steps to
efl'ectually check its apparently capricious career.

A NEW contrivance for reading the position of the pointer in
sensitive balances is described by W. H. F. Kuhlmann in the
Zeilschrift fiir Instrumentenkunde. It has often been at-
tempted to save time by accurate readings with the aid of a
tekscope or microscope, but none of those methods have been
found to answer the purpose of the practical chemist or
physicist. Herr Kuhlmann's contrivance is at once simple .ind
effective. The pointer moves he/iind \h& divided scale, and the
face of the latter is turned towards a concave cylindrical mirror
attached to the central column of the balance. This mirror can
be adjusted to face the observer, who sees in it a magnified
image of the pointer rapidly moving across the magnified
scale. It is thus made possible to graduate the scale much more
finely than heretofore. The pointer must be very fine at the
end, but any danger of its being damaged on that account is
obviated by the fact of its moving between the scale and the
mirror, .\nolher improvement, described by Dr. Classen in
the same number, is an arrangement for exchanging objects and
weights without opening the balance case. This is accomplished
by making a portion of the scale pans detachable. Each scale
pan consists of a set of bent rods. One of these, bent into an
irregular shape, can be lifted out and conveyed on a circular
rail to the other scale pan, the latter undergoing this oper.-ilion
at the same time. A double weighing is no more troublesome
than a single weighing, and the advantages of the method,
especially when absolute weights are required, are obvious.

The phenomenon of polyembryony, or the development of
two or more embryos in a single seed, has been the subject of
several investigations. It has been shown that it may be dye
to the division of the nucellus, or to the fusion of two ovulei,
or to the presence of several embryo-sacs in one ovule. Further,
Strasburger has found that it is often to be accounted for by the
ingrowth of some cells of the nucellus into the embryo-sac,
which there develop into adventitious embryos ; in other cases
he ascertained that two egg-cells are normally present in the
embryo-sac, which on fertilisation give rise to two embryos.
Finally, Dodel and Overlon showed that it was possible for the
synergid.-c to develop into embryos. More recently, M.Tretjakow,
in a short but interesting paper {Ber. d. Deutsclt. Bol. Gtsell.,
February 1895) describes yet another cause of polyembryony.
In Allium odorum, in addition to the normal embryo formed
from the egg-cell, not infrequently the antipodal cells also give
origin to embryos. Sometimes only one of these develops, but
M. Trctjakow has observed all three antipodal cells start into
growth and give rise to three embryos. These antipodal embryos
commence their development immediately after the fertilisation
of the egg-cell, and the cell divisions, at least in the earlier
stages, correspond exactly with those in the embryo formed from
that cell. The Russian author, accepting the view that the
antipodal cells are homologous to the vegetative cells of the
prothallia of ferns, compares these antipodal embryos with those
arising by apogamy on fern prothallia.

April 4, 1895]

NA TURE

541

In the course of a few remarks made by Prof. D. E. Hughesi
F.R.S., at the recent banquet given by the staff of the National
Telephone Company, some points in connection with the early
history of telephony were mentioned. The text of the speech
is published in the EUclricai Engineer for March 22, and the
following note from it is interesting. Prof. Hughes said : —
The earliest record of a perfect theoretical electiic telephone,
was contained in Du Moncel's " Expos<-'e des Applications,"
Paris, 1854 ; when M. Charles Bourseul, a French telegraphist.
conceived a plan of conveying sounds and speech by electricity.
Suppose, he explained, " that a man speaks near a movable
disc sufficiently flexible to lose none of the vibrations of the
voice, that this disc alternately makes and breaks the current
from a battery ; you may have at a distance another disc which
will simultaneously execute the same vibrations." Unfor-
tunately M, Bourseul did not work out his idea to a practical
end, but these few words contain the shortest possible explana-
tion of the theory of the present telephones.

It is now exactly thirty years since Prof. Hughes first ex-
perimented with a working telephone. In 1865, being at St.
Petersburg in order to fulfil his contract with the Russian
Government for the establishment of his printing telegraph
instrument upon all their important lines, he was invited by his
Majesty the Emperor Alexandre II. to give a lecture before his
Majesty, the Empress, and Court at Czarskoi Zelo, which he
did ; but as he wished to present to his Majesty not only his own
telegraph instrument, but all the latest novelties. Prof. Philipp
Reis, of Ftiedericksdorf, Frankfort-on- Maine, sent to Russia
his new telephone, with which Prof. Hughes was enabled to
transmit and receive perfectly all musical sounds, and also a
few spoken words, though these were rather uncertain, for at
moments a word could be clearly heard, and then from some
unexplained cause no words were possible. This wonderful
instrument was based upon the true theory of telephony, and it
contained all the necessary organs to make it a practicable suc-
cess, lis unfortunate inventor died in 1874, almost unknown,
poor, and neglected ; but the German Government have since
tried to make reparation by acknowledging his claims .as the
first inventor, and erecting a monument to his memory in the
cemetery at Friedericksdorf.

Since the enunciation by Virchow, in 1858, of his theory
of cellular pathology, much attention has been given to
the study of this unit. Nearly all the unsolved prob-
lems of medical science involve, in one way or another, the
consideration of some one of the functions of the cell. At
the Philadelphia Academy of Natural Sciences, on February 5,
Dr. C. L. Leonard directed attention to a new method of
studying one of these functions. The method consists in
making a consecutive series of instantaneous photomicro-
graphs of the same microscopic field, taken at definite
intervals, so that a comparative study of the series can
afterwards be made. The results obtained by this method are
the elimination to a greater extent of the personal equation of
the observer, the procuring of incontestable proof of phenomena
observed, the extension of the observations over any length of
time, and the possibility of studying the changes occurring over
the entire field at any one moment. The method also enables
the student to study the condition of a fresh, living, unstained
specimen for any length of time, in fields taken at definite
atervals. So far Dr. Leonard has confined the greater part of
his study to cell motion as exemplified in the movements of the
red and white blood corpuscles. He exhibited to the Academy
a number of photomicrographs illustrating the amccboid motion
of the white blood corpuscle, and also showing motion in the red
blood corpuscle. Some of the photographs seem to show that

NO. 1327, VOL. 51]

diapedesis is not a filtration due to pressure, but is due to a
truly amoeboid motion and power of the red blood corpuscles.
Further photographs illustrated the position of the corpuscles
within the capillaries, and showed the presence of nuclei in the
red corpuscles of the frog while in the living tissues.

At a recent meeting of the Paris Academy, M. Desire
Korda read a paper on a " thermochemical carbon
cell." The author finds that if barium peroxide is
heated to redness in contact with a carbon plate, the
oxide becomes reduced to baryta, and a difference of poten-
tial of about one volt is produced, the carbon plate being
negative. A similar result was obtained with cupric oxide as
soon as a layer of potassium carbonate was placed between the
oxide and the carbon, the difference of potential in this case
amounting to II volts. The experiments were in each case
performed by connecting a plate of gas-retort carbon by means
of a platinum wire to one terminal of a Richard voltmeter, and
placing on the carbon a few c.c. of the salt. A platinum wire
dipping in the salt served to complete the circuit. On heating
the carbon to a dull red heat in a Bunsen flame, a violent
effe rvescence takes place, carbon dioxide being evolved, and
the voltmeter shows a deflection corresponding to about I volt.
T his deflection remains constant as long as any of the higher
oxide is left.

Readers of Mr. Edward Step's books and magazine articles
on popular botanical subjects, will be pleased to learn that he
has writ ten a pocket-guide to British wild flowers, to be pub-
lished by Messrs. Frederick Warne and Co. The title of the
book will be "Wayside and Woodland Blossoms."

The fourth part of " Dissections Illustrated " (Whittaker
and Co.;, by Mr. C. Gordon Brodie, containing sixteen mag-
nifi cent plates drawn and lithographed by Mr. Percy Highley,
has just appeared. Students of human anatomy could hardly
des ire a handbook in which typical dissections are more clearly
displayed than they are in Mr. Brodie's work, which has now
been completed. The whole work contains seventy-three
coloured plates.-diawn to two-thirds natural size.

The Zoological Society of France has just published a new
edition of the " Rules of Nomenclature of Organised Beings
adopted by the International Congresses of /oology (Paris,
1889 ; Moscow, 1892)." A copy will be sent gratis to every
professor of zoology or comparative anatomy, director of a
museum, library or laboratory, or assistant in the same, also to
every learned society, upon application to the general secretary,
M. le Dr. R. Blanchard, 7 Kue des Grands Augustins,
Paris.

The valuable work in zoology, carried on in H.M. Indian
Marine surveying steamer Investigator, under Commanders
A. Carpenter and R. F. Hoskyn, is already known to many
biologists, ar.d Part I. of the illustrations referring to it,
now obtainable through Mr. Bernard Quaritch, should make
it known to more. The Part contains seven splendid photo-
etchings representing twenty-six remarkable fishes, and five
illustrative of Crustacea. The former were prepared under the
direction of Mr. A. Alcock, and the latter under the direction
of Mr. J. Wood-Mason.

Prof. S. H. Vines' "Students' Text-book of Botany"
(Swan Sonnenschein and Co.), the first half of which was
reviewed in these columns in October last (vol. 1. p. 613), has
just been published in its complete form. In addition to the
sections mentioned in our notice, the work now contains
descriptions of the Phanerogams, and the part on the physiology

542

NA TURE

[April 4, 1895

of plants. The whole volume makes a comprehensive text-
book of botany possessing many excellent features, and of the
usefulness of which there can be no question. It is a pity that
so very many literal errors should have been overlooked while
the work was passing through the press. The page of errata
which precedes the contents is not the sort of thing one looks
for in a new book.

The first BulUlin of the Bohemian Academy of Sciences,
founded in 1890 by the Emperor of Austria, has just been
issued. It contains no less than twenty-three separate memoirs
many of which are beautifully illustrated with coloured and other
plates, amongst which we may specially mention the twelve
successfully-executed photographs illustrating some bio chemical
studies by MM. Kruis and Rayman. There are French, German
and Italian communications, so that the BulUtiii may with
justice be called "International." Science is very variously
represented, and we find contributions in the departments of
mathematics, biology, chemistry, geology, physics, physiology,
and bacteriology. The committee of publication is to be con-
gratulated, not only on the high standard of the original work
here brought together, but also on the successful manner in
which they have produced this journal. In addition to the
plates, the printing and paper are both excellent.

The Report of the Council of the Scottish Meteorological
Society, on March 27, shows that the work of the Society is
extending. K new station his been established in connection
with the Society at Kingussie, Inverness-shire, the instruments
for which were supplied chiefly by Mr. John Anderson. The
station is under the management of Dr. De Wattville, who
commenced the observations on January i. The work at the
two I'en Nevis observalorie;, made both with the eye and
■ontinuously recording instruments, has been carried on with
ihe same zeal and success as in previous years. Much work
has been done in the offices in Edinburgh and Fort-William in
recopying, on daily sheets, the hourly observations of the two
observatories, in connection with an examination of a compari-
son of Ihe two sets of observations in their bearings on the
storms and weather of North-Western Europe. Thisexamini-
tion has been recently commenced by Dr. Buchan. The subject
is divided into these several parts — cyclones ; anti-cyclones; small
differences of temperature between top and bottom, including
Inversions of temperature ; very large difierences of tem-
peratuic ; grea'. dryness of air at the top ; marked differences of
wind at top and bottom, both as regards direction and force ;
relations to reported storms at the lighthouses ; conditions
under which very diverse readings of the two barometers occur.
In each of these cases the weather charts of Europe at the time
are thoroughly examined from variou; points of view. Several
of the points examined have already been investigated to some
extent ; but what is now attempted to be done is an inquiry into
their relations to each other. The importance of the inquiry
consists in the fact that the high-level station dealt with is
situated right in the general path of the cyclones of North-
western Europe, whereas the other high level stations of
Europe that have been used in similar investigations are
altogether outside that path. Dr. Buchan has a stupendous
piece of work under way, and we trust that it may soon be
brought to a successful termination.

Thk additions to the Zoological Society's Gardens during the
past week include a Vervct Monkey (Ccrcopitliecu! In'.aiidii, 9 )
from South Africa, presented by Mr. H. W. Weguelin ; a
Rhesus Monkey {Afataciis rhesus, J ) from India, presented
by Mr. W. II. Ilayner ; a ParJinc Genet (Genella pardina)
from West Africa, presented by Mr. George Danes ; a Palm
Squirrel {Sciurus falmaium) from India, presented by
Mri. Henry Jones; a Short-tailed Wallaby {/falmaliiriis
NO. 1327, VOL. 51]

hrcuhyurtis, 9 ) from (^>ueensland, presented by Mrs. L.
Thompson ; a Vulpine Phalanger {I'halangista vulpina, 9 )
from Australia, presented by Master John Simonds ; a Bronze-
winged Pigeon (Phafs chakopltra, i) from Australia, pre-
sented by Lady Buchan Hepburn ; a Grey-brea-ted Parrakeet
(Bolborhymhiis monaclius) from Monte Video, presented by
Mr. Rowland Ward ; an Egyptian Jerboa (Dipus a^pfins)
from North Africa, an Oak Dormouse {.Vyoxus Jryas), South
European, presented by Dr. G. L. Johnson ; a Cape Viper
(Causus rhombeatits) from South .\frica, presented by Mr. J.
E. Matcham ; a Hoolock Gibbon (Hylobates hoohck, i ) from
Assam, two Gazelles (Gazella dorcas, f, 9) from Nubia, an
Oak Dormouse (Myoxtis dryas). South European, deposited ;
a Brazilian Three-banded Armadillo (7'i>/)'/rt</« tricincliis, i\
from Brazil, a Variegated Bittern (Ardella itndiicris), a White-
spotted Rail {Kallus macnlatus), a Sooty Rail {Raltiis
rythyrhynchus), a Rosy-billed Duck {Mdopiana peposaca),
four Burrowing Owls (Speotylo (utiicularia) from South
America, purchased.

OUi< ASTRONOMICAL COLUMN.

Comet e 1S94 (Swiir). — The general resemblance of the
orbit of this comet to that of De Vico's, 1S44 I, was noticed
very soon after its first appearance (Nature, vol. li pp. 132,
160). Mr. Barnard was, fortunately, able to determine the
place of the comet on five nights at the end of January, when
it was "most excessively faint and ditVicult, about 10" to 15"
in diameter,'' as seen with the 36-inch refractor. These ob-
servations have enabled Dr. Chandler to revise the elements of
the orbit, and to undertake a discussion of the possible identity
with the comet of 1844 (Aslronomifa! youinal, No. 338).
Dr. Chandler points out that in view of the numerous close
family resemblances among the periodic comets, we can dis-
tinguish between similarity or identity in the present case only
by actual calculation of the principal planetary perturbations.
He has accordingly calculated the perturbations, and he finds
that " both in direction and approximate amount these changes
are uniformly of the character required to lec )ncile the differ-
ences between the observed orbits of the comets 1844 1 and
e 1894." Some of the results are shown in the following table,
the elements for the 1S44 comet being those of Brunnow : —

<■ 'S94

1844 I - — ^

Before perturb. Observed.

Longitude of perihelion
,,_ ,, node ...

Inclinatiun

Eccentricity

Perioil

278 486 .
64 ao

2 549 •

o'6i765 .,

5'4C)6 yc.irs .

383 7-5 .
60 24

s 53 ' •

0*60283 .

5 6 1 5 ycirs .

296 34-1
48 407

3 57 '9
0-5719
5 "863 years.

Dr. Chandler considers this to be " sufficiently demonstrative
of the high probability of identity to justify a more refined
calculation at a proper future time." As to future observations
of the comet, he is not very hopeful. " The present perihelion
distance will probably be changed by Jupiter in 1S97 to one
considerably beyond the orbit ol Mars, so that unless a favour-
able reversion of the change of brilliancy which apparently
took place between 1844 and 1S94 should occur, it will in all
likelihood hereafter be invisible ; at least until, at some future
approach to the critical point of disturbance near longitude
165", simultaneously with Jupiter, it shall be thrown into a path
in which, near perihelion, it will be again in reach of our
telescopes."

A Possible New Satellite of Neptune.— In the course
of a series of micrometric measures of the satellites of Uranus
and Neptune, Prof. Schaeberle observed a suspicious object
near to Neptune on September 24, 1S92, when the seeing was
exceptionally fine {Aslioiiomical yoiirnal. No. 340). The star
or satellite was so faint that it was near the limit of vision of
the 36inch refractor of the l.ick Observatory. During an hour
and forty minutes, the total change of position angle w.as 2"
greater than could be accounted fur by the geocentric motion of
the planet with reference to a fixed star, and this strengthens
the idea that the object observed may have been a second
.satellite. At the time of observation the distance from the

April 4, 1895J

NATURE

54.3

planet's centre was 24" '4. Prof. Schaeberle now somewhat re-
luctantly publishes these facts in connection with his measures
of the known satellite, as he has not on any subsequent occasion
been able to detect any object in the neighbourhood of Neptune
in apparent orbital motion about the planet. The unusual
clearness and steadiness of the night of September 24, 1892,
however, is not considered to have been equalled in the later
observations.

PROFESSOR MENDELEEFF ON ARGON.

A T the meeting of the Russian Chemical Society, on March
•'*■ 14, Frof. MendelJeff made some interesting remarks on
the relations of argon to the periodic system. His views are
summed up as follows in a proof-issue of the Proceedings of the
Society : —

" .-Vs regards argon we must consHer, first, whether it is a
chemical individual, or a mixture, and then, whether it is a
simple or a compound body. The supposition that it be a mix-
ture, lies beyond all probabilities ; it is contradicted by the re-
searches of Olszewski into the liquefaction and solidification of
argon. The supposition that it may be a compound has also
little in its favour. The remark .ible inactivity of argon testifies
in favour of its being a simple body, although there are, of
course, some compounds, al-o endowed with the same property
to some extent. The spectrum of argon, too, is characteristic
of a simple body.

" Taking it as a simple body, we must then consider its pos-
sible atomic weight, the weight of its molecule being .lear to 40
{although, probably, a little over 40, because of a slight mix-
ture of nitrogen with llie argon). The atomic weight of argon
evidently dejiends upon the number of atoms which its molecule
contains. We must, therefore, consider the series of possible
molecular formulse : A, A.j, A3, . . . A„.

" Upon the first supposition. A, the atomic weight of argon
would be about 40, and, like cadmium and mercury, it would
be a monatomic gas.

" In favour of this supposition we have the specific heat
ratio at constant volumes and pressures, K, found by Rayleigh
and Ramsay to be near to r65, i.e. to the value which is con-
sidered as characteristic for monovalent gases. It must, how-
ever, be borne in mind that K varies for compound molecules,
even when these last contain the same numbers of atoms ; thus,
for most bivalent gases (nitrogen, oxygen, &c.) K is near to
I '4, while for chlorine it is I '3. This last figure makes one
think thai K depends not only upon the number of atoms in the
molecule, but also upon chemical energy, that is, upon the
stock of internal motion which determines the chemical activity
of a body, and the quantity of which must be relatively great
with chlorine. If, with the chemically-active chlorine, K is
notably less than i 4, we m.iy admit that for the inactive
argon it is much more than I '4, even though the molecule of
argon may contain two or more atoms.

"If we admit that the molecule of argon contains but one
atom, there is no room for it in the periodic system ; because,
even if we suppose that its density is much below 20 (although
this is very unlikely to be the case, and the contrary could rather
be surmised), and that the atomic weight of argon should fall
between the atomic weights of chlorine and potassium, the new
body ought to be placed in the eighth group of the third series ;
but the existence of an eighth group in this series could hardly
be admitted. In fact, an eighth group is characteri^^ic of the
large periods ; and it establishes a link between the metallic
elements of the seventh groups of the even stries, with the
metallic elements akin to them, of the first groups of the uneven
series. It appears, therefore, very unlikely that the atomic
weight of argon might be about 40.

" Upon the second supposition (A.j), its atomic weight would
be about 20, and in such a case argon would find its place in
the eighth group of the second series, i.e. after lluonne. Uut
the same objections as above could then be raised. Fluorine
and sodium are, moreover, strikingly unlike to each other.
However, it must be said in favour of this hypothesis that it
would have the advantages of analogy, by giving a new eighth
group to an even series. If we take also into consideration that
the typical series are possessed of several peculiarities, we may
be justified, to some extent, in supposing that the atomic weight
of argon is 20, this hypothesis being already much more
probable than the former (A = 40).

NO. 1327. VOL. 51]

" If we suppose, further, that the molecule of argon contains
three atoms, its atomic weight would be about 14, and in such
case we might consider argon as condensed nitrogen, Nj.
There is much to be said in favour of this last hypothesis.
First of all, the concurrent existence of nitrogen and argon in
nature ; then, the fact that many of the bright lines of the two
spectra are very near to each other. Then, again, the in-
activity of argon would be easily explained, if it originates from
nitrogen, N„, with giving up heat. And finally, the fact of its
having been obtained, though in a relatively small quantity,
from artificially obtained nitrogen. The supposition of Rayleigh
and Ramsay, according to which argon has been disengaged in
this last case from water, is very probable, but at any rate it is
not yet proved. The hypothesis of argon being condensed
nitrogen might be tested by means of introducing boron, or
titanium, into an atmosphere of argon, strongly heated, and
through which electric sparks would be passed.

"If we suppose, next, that the molecule of argon contains
four or five atoms, its atomic weight will be 10, or 8, and in
such case there is no room for argon in the periodic system.

" And finally, if we admit that its molecule contains six
atoms, and that its atomic weight is 65, we must place it in
the first series. In such case, it would probably take its place
in the fifth group. Accordingly, the suppositions that argon is
condensed nitrogen, N^, or that, containing six atoms in the
molecule, its place is in the first series of the system, appear to
be the more probable ones, if it is a pure simple chemical body.

"Fiom a letter received by D. I. Mendeleeff from Prof.
Ramsay, it appears that the investigation of argon is being
continued, and that the body finds its place in the periodic
system ; but the ultimate results of the researches of the two
authors, who have brought before chemistry such an important
new problem, and given it such an exemplary investigi'.ion, ari
not yet known."

TERRESTRIAL HELIUM {^).

W

E referred last week to Prof. Ramsay's discovery of another
new gas obtained from cleveite. The following papers,
by Prof. Ramsay and Mr. Crookes, on this subject were com-
municated to the Chemical Society at its anniversary meeting.

Prof. Ramsay's paper was as follows : —

In seeking a clue to compounds of argon, I was led to repeat
experiments of Hillebrand on cleveite, which, as is known,
when boiled with weak sulphuric acid, gives off a gas hitherto
supposed to be nitrogen. This gas proved to be almost free
from nitrogen ; its spectrum in a Ptliicker's tube showed all the
prominent argon lines, and, in addition, a brilliant line close
to, but ;iot coinciding with, the D lines of sodium. There are,
moreover, a number of other lines, of which one in the green-
blue is especially prominent. Atmospheric argon shows, be-
sides, three lines in the violet which are not to be seen, o--, if
present, are excessively feeble, in the spectrum of the gas from
cleveite. This suggests that atmospheric argon contains, be
sides argon, some other gas which has as yet not been separated,
and which may possibly account for the anomalous position of
argon in its numerical relations with other elements.

Not having a spectroscope with which accurate measure-
ments can be made, I sent a tube of the gas to Mr. Crookes,
who has identified the yellow line with that of the solar element
to which the name " Helium" has been given. He ha; kindly
undertaken to make an exhaustive study of its spectrum.

I have obtained a considerable quantity of this mixture, and
hope soon to be able to report concerning its properties. A
determination of its density promises to be of great interest.

The spectrum of the gas was next discussed by Mr. Crookes,
V, ho said

By the kindness of Prof. Ramsay I have been enabled to
examine spectroscopically two P.'lucker tubes filled with some of
the gas obtained from the rare mineral cleveite.' The nitrogen
had been removed by " sparking." On looking at the spectrum,
by far the most prominent line was seen to be a brilliant yellow
one apparently occupying the position of the sodium lines.

1 Clcvcile is a variety of uraninite, chiefly a tiranate of uranvlc, lead,
and the rare carlhi. It conrains abouti^ per cent, of the rare eartht. and
at>out 3's per cent, of a gas said to be nitrogen.

544

NA TURE

[April 4, 1S95

Examioation with high powers showed, however, that the line
remained rigorously single when the sodium lines would be
widely separated. On throwing sodium light int > the spectro-
scope simultaneously with that from the new gas, the spectrum
of the latter was seen to consist almost entirely of a bright
yellow line, a little to the more refiangible side of the sodium
lines, and separated from them by a space a little wider than
twice that separating the two sodium components from one
another. It appeared as bright and as sharp as D, and Do.
Careful measurements gave its wave-length 5S7 '45 ; the wive-
lengths of the sodium lines being D, 589'5i, and DjSSS'gi.
The differences are therefore —

D,

D..

\Va\"e-length>;.

589-51

DiiTerences.

o'6o

I '46

588-91

New line 587-45

The spectrum of the gas is, therefore, that of the hypothetical
element Helium, or Dj, the wave-length of which is given by
Angstnim as 5S7-49, and by Cornu as 587-46.

Besides the Helium line, traces of the more prominent lines of
argon were seen.

Comparing the visible spectrum of the new gas with the band
and line spectrum of nitrogen, they are almost identical at the
red and blue end, but there is a broad space in the green where
they differ entirely. The Helium tube shows lines in the follow-
ing positions : —

Wave-length.

(a) D3, yellow 5S7-45 Very strong. Sharp.

(b) Yellowish green ... 568-05 Faint. Sharp.

(0 Yellowish green ... 566-41 Very faint. Sharp.

(d) Green 516-12 Faint. Sharp.

(^) Greenish blue ... 50081 Faint. Sharp.

(/) Blue 480-63 Faint. Sharp.

I have taken photographs of the spectrum given by the Helium
tube. At first glance the ultra-violet part of the spectrum looks
like the band spectrum of nitrogen, but closer examination
shows considerable differences. Some of the lines and bands
in the nitrogen spectrum are absent in that from the Helium
tube, whilst there are many fmc lines in the latter which are
absent in nitrogen. Accurate measurements of these lines are
being taken.

ISOLATION OF FREE HYDRAZINE, N^Hy

VT LOBRY DE BRUYN contributes a memoir of special
interest to the current issue of the iPc-i-H-'iV das Travaux
Chimiques des Pays-Bos. It is not long since the distinguished
Amsterdam chemist succeeded in preparing for the first time
free anhydrous hydroxylamine, and now he announces that he
has likewise been successful in isolating free hydrazine by a
similar method. Eight years ago the important discovery of
hydrazine »-as made by Prof. Curtius, and since that time the
amount of knowledge which has been accumulated concerning
the base and its compounds by Prof. Curtius and his assistants
is so large that a separate volume might well be devoted to it.
Nevertheless, the free anhydrous base itself has not hitherto
been satisfactorily prepared ; indeed it would now appear, in
the light of M. dc liruyn's remarkable work, ihit it has not
hitherto been in any way isolated. The h) Irate of the base has
been obtained in the pure state and fully described by Prof.
Curtius, hut in his later communications he has expressed the
view that the free base is so uns'.ahle that most probably it is
incai>able of separate existence. The hydrate only is produced
when the salts arc decomposed by a caustic alkali, and even
iligestion in a Bcilcd tube at 170 with anhydrous baryta, h.as
failed to detach the water molecule from its combination with
hydrazine. It appeared, however, to M. de Bruyn that the
nature of the salts and other compounds of hydrazine rendered
it scarcely probable that the base was less stable than hydroxy-
lamine, and he considered it not unreasonable to hop: that it
might therefore be isolated in an an,alogous manner to the latter
laic, namely, by reacting upon the chl iride with solium
methylate in methyl alcohol solution. The experiments made
in this direction are only preliminary, but their result is so
interesting that an account of them i; at once published.

The salt employed was the chloride N.Hj.HCI, prepared as
described by Prof. Curtius. Ten grams of this salt in powder
were added to 200 c.c. of pure methyl alcohol, and a solution
of the calculated quantity of sodium methylate CHjONa in
methyl alcohol were subsequently added. Common salt was
immediately precipitated without any perceptible rise of tem-
perature. The mixture was consequently boiled for half an
hour in a flask fitted with an upright condenser. After cooling
the sodium chloride was removed by filtration, and the solution
submitted to distillation. At first mainly methyl .alcohol p.assed
over, but after a time the distillate began to contain augmenting
quantities of hydrazine ; the pressure was then reduced, and four
further quantities separately collected. The temperature of
ebullition rose to 55°, although the pressure was materially re-
duced. The last 20 c.c. contained the greater portion of the
base. This last fraction was then again distilled at the ordinary
pressure, until a residue was left which contained 73 per cent,
of hydrazine. The hydrate of hydr.azine only contains 64 per
cent, of the base, hence it was evident that some free hydrazine
had been obtained, and that hydrazine is a comparatively stable
substance boiling at a temperature higher than that of methyl
alcohol.

In a second experiment 42 grams of chloride of hydrazine
were treated in a similar manner with methyl alcohol .and
sodium methylate. This larger quantity evinced some rise of
temperature after the admixture, and the heat caused by the
re.action of the hydrazine chloride, which at first had not all
dissolved, «-as just sufficient to keep the liquid boiling for several
minutes, when once it had been brought to the boiling point by
extraneous heating. After the conclusion of the reaction
the contents were cooled, avoiding the access of moisture and
carbon dioxide, the sodium chloride filtered off as before, and
distillation proceeded with, at first in an ordinary distillation
apparatus and afterwards with the aid of a Le Bel-Henninger
apparatus. A residual 40 c.c. was again fractionated under
reduced pressure and six portions collected. The sixth friction
contained no less than 82 6 per cent, of N„Hj. A smaller
quantity passing over after removing the sixth fraction contained
over 84 per cent. The fifth and sixth portions solidified when
cooled by a freezing mixture of ice and salt. The crystals
mt Ited about 4°. Although the crystals when exposed to the
air exhaled dense white fumes, owing to the attraction of
moisture, a number of them were quickly pressed between
cooled blotting paper, weighed, and volumelrically analysed.
The analytical numbers corresponded to 92 per cent, of NjH^,
a result which, considering the extremely hygroscopic nature of
the crystals, would appear to indicate that they consisted of
practically pure N„Hj. The dried crystals melted at -1°
to -2°.

A drop of the liquid obtained by fusion of the crystals did
not explode when heated with a naked flame ; a yellow flame
was produced, however, accomjianied by a hissing noise. The
liquid base is heavier than water and considerable heat is
evolved upon mixing it with a small quantity of the latter liquid.
Dry oxygen slowly oxidises it. When paper is moistened with
a drop of hydrazine and exposed to the air, it becomes hot
spontaneously and fumts strongly. Crystals of sulphur dissolve
promptly in the liquid base with considerable rise of tempera-
ture and formation of a reddish-brown liquid whose odour
reminds one of ammonium sulphide ; upon the addition of
water to this liquid, sulphur is precipitated. The halogens
react very violently with hydrazine, producing their acids, and
liberating nitrogen. Iodine disappears instantly, and a quanti-
tative experiment showed that the reaction proceeded in accord-
ance with the equ.alion NjIIj ••- 2[„ = N3 -f 4HI. Potassium
permanganate or bichromate act with great violence upon the
licjUid base, but the reaction is unaccompanied by either incand-
escence or explosion. The liquid appears to possess the further
property of readily dissolving many salts, such as the potassium
salts of (he halogen acids, and nitre.

It would thus appear that, instead of being a gas, as at first
supposed by Prof. Curtius, free hydrazine is at the ordinary
tcmiicralure a liquid, which, however, solidifies at a tempera-
lure in the neighbourhood of that of the freezing-point of water,
to colourless crystals. The base is, moreover, endowed with ■
very much higher degree of stability than was suppo.sed. M.
de liruyn is now engaged in preparing it upon a very much
larger scale, in order more completely to study its properiies.

A. E. TUTTON.

NO. 1327, VOL. 51]

April 4, 1895]

NATURE

54:

M'

SCIENCE IN THE MAGAZINES.
R. CHAS. DIXON has discovered a new law of geo-
graphical dispersal of species, and he expounds ils cap-
abilities in the Fortnighlly. Here is a statement of his con-
clusions : — "Species in the northern hemisphere never increase
their range in a southern direction; they may do so north, north-
east, or north-west, east or west. Species in the southern hemi-
sphere never increase their range in a northern direction ; they
may do so south, south-east, or south-west, east or west. The
tendency of life is to spread in the direction of the poles.
Among the six corollaries which I have drawn from this law,
mention may be made of the following. By the fourth corollary,
species never retreat from adverse conditions. If overtaken by
such they perish, or such portion of the species that may be ex-
posed to them. I5y the fifth corollary, extension of range is
only undertaken to increase breeding area. By the sixth
corollary, contraction of range is only produced by extermin-
ation among sedentary species, and probably also by extermin-
ation (through inability to rear oflTspring) among migratory
species that are neither inter-polar nor inter-hemisphere. . . .
If this law of geographical distribution be true, polar
dispersal of species — in other words, from the direction
of the poles towards the equator — is a myth." Mr.
Dixon brings forward a number of facts in support of his
theory, which will no doubt be given the consideration it
deserves.

An address by Mr. Leslie Stephen, on the choice o'' books,
appears in the National ; but, to prevent misconception, it is
just as well to state at once that scientific literature is altogether
ignored. Yet it is difficult to understand why this should be,
for writings of men of science are apparently included in the
definition stated by Mr. Stephen himself. " Literature, in short,"
he writes, "is one utterance of Matthew .Arnold's Zeitgeist
— the v,-»gue but real entity which is a summary of all the sym-
pathies and modes of thought and feeling characteristic of the
best minds at a given stage of human progress." A few natural
history notes will be found in the .\'a!ioiial, in an account, by
Miss Balfour, of a journey through the British South Africa
Company's territory, in 1894.

Among other popular articles on natural history in the maga-
zines received by us, we notice " Nestlings," by the Rev.
Theodore Wood, in the Sunday Magazine, and " Snake-
Taming" in Chambers' s yournal. This periodical also con-
tains a very readable elementary description of the great Indian
Trigonometrical Survey. Mr. L. N. Badenoch describes a
! number of species of Plasmidse in Good Words. In the same
magazine Sir Robert Ball writes on (he life and works of Coper-
nicus. Under the title, "Tesla's Oscillator and other Inventions,"
a good account of some of Mr. Tesla's recent electrical work is
given in the Century, by Mr. T. C. Martin. The article "dis-
closes a few of the more important results he has attained, some
of the methods and apparatus which he employs, and one or
two of the theories to which he resorts for an explanation of
what is accomplished." It is illustrated with fifteen figures,
all of which possess points of interest. Mention must be made
here of a short biographical sketch of Helmholtz, contributed by
Mr. Martin to the Slarch number of the Century, but overlooked
at the time. The sketch is illustrated bv a fine engraving from
a photograph of Helmhollz, taken in 1893. A brief note in
CasseU's Family Magazine describes some curious tubular
dwellings constructed against the side of a small aquarium by
the species Ampliitho: litlorina. The tubes are semicircular,
and composed of sand and small pieces of seaweed, ce-
mented together with a glutinous mailer secreted by these
shrimps.

The practicability of constructing a railway from the Mediter-
ranean to India is discussed by Mr. C. E. D. BK-ick in the
Contempcra)y. Over India proper there are 18,500 miles of
lines open to traffic. But westward these lines break off at
Peshawur, Chaman, and Kurrachee. It is proposed that a line
should be constructed from Port Said, through Northern Arabia,
along the edge of the Persian Gulf, to Kurrachee— a di»tance
estimated at 2400 miles.

In addition to the magazines mentioned in the foregoing, the
Humanitarian, Scribner, and Longman's Magazine have
been received. A portrait of Prof. Bonpey accompanies
an article on " Science and Faith " in the first of these
magazines.

NO. 1327, VOL. 51]

PRECIOUS STONES, AND HO IV
DISTINGUISH THEM.^

TO

A MONG the duties which fall to the lot of an official in the
•^~*- Mineral Department of the British Museum, in his other-
wise unromantic and sternly studious life, is one which is not
altogether devoid of human interest. It may happen, for
' example, that a lady having inherited a priceless heirloom in
i the shape of a large emerald, travels from the Antipodes in
order to sell it in England for its true value, and desiring to
display its charms brings it to the Museum. To inform such a
person that the stone is but green bottle glass cannot be a
pleasant task.

Only within the last few months came an Afghan prince
who had sold his worldly goods, travelled to the coast of India,
and worked his passage to England, having secreted about his
person a stone which he supposed to be of enormous value.
His story was that as he slept upon the hillside, Mahomet had
appeared to him and told him that he would find a rare jewel
under his hand. The poor man could not be convinced that a
stone with this celestial guarantee could be anything common;
for, as he said, "Mahomet cannot lie." Be this as it may,
the stone was quartz, and its princely owner could only be
advised to repair his fallen fortunes in some Oriental fashion at
Constantinople — Kensington.

It is curious that the stones brought by such people are always,
in the opinion of their owners, gems of the greatest value and
rarity. Could they but have consulted some competent expert
nearer home, they would have been saved time and money and
bitter disappointment.

But after such interviews, I have always been very forcibly
impressed by the fact that even the experts do not seem in the
least aware of the simple and certain methods which have been
placed at their disposal by recent mineralogical research. There
is, perhaps, no subject in which experts have been so slow to
I take advantage of practical methods supplied by science as in the
manipulation and discrimination of precious stones.

The stones brought by these chance visitors have often been
bought and sold over and over again under totally false names.
\ There is, I suspect, scarcely a collection, public or private, in
which some of the jewels are not wrongly described.

Mistakes are constantly made ; and these are sometimes of
considerable commercial importance. It may be remembered,
for example, that a few years ago much excitement was caused
by the discovery of rubies in the Macdonell Range in Southern
Australia. Much time and money was wasted in their extrac-
tion before it was discovered that, like the so-called Cape rubies,
they were merely garnets.

I should be the last person to underrate the great value of
that knowledge which results from long experience, or to deny
that in ninety-nine cases out of a hundred an expert may be
absolutely right. Every one must admire the confidence with
which a practised eye can even pick out from several packets of
diamonds those which came from a certain mine.

Such a professional expert may in five seconds pronounce a
judgment which it might require half an hour to establish by
scientific methods, and one which may be equally correct.

But there is a vast difi'erencc between "maybe" and "is,"
and scientific men are not satisfied with that sort of judgment,
but require actual proof.

One ought to distinguish between two sorts of expert know-
ledge— that which results from long experience and the training
of eye and hand, and that which results from familiarity with
, scientific methods. To have confidence in the non-scientific
expert, one must place reliance upon his personal character and
the soundness of his senses, and be sure that liis .actual ex-
perience has included problems similar to the one submitted to
him, and even then he may fail in that hundredth case.

But the scientific tests cannot err ; moreover, they furnish
\ a proof which carries conviction to .all who see it. The opinion
of the expert need convince none but himself.

An exact parallel is lo be found in medical practice. It is
no doubt often possible for a doctor of experience to diagnose
diphtheria and phthisis by their symptoms. But in recent years
new methods have been made available by the discoveries
relating to bacteria, and at the present time no diagnosis of
diphtheria or of the early stages of consumption would be con-

* A lecture delivered at the Imperi.il Institute, by Mr. H. A. Micrs.

546

NA TURE

[April 4, 1895

sidered complete which did not include the bacteriological
evidence ; that is to say, the isolation and microscopic examina-
tion in each case of the specific bacillus. %Yhat is more, such
evidence is proof positive of the existence of the disease.

Now the only characters at all generally employed by persons
connected with the trade in precious stones are two — namely,
the hardness and the specific gravity or weightiness.

I f a stone scratches quartz, and is scratched by topaz, it is said
to have a hardness between that of quartz and that of topaz ;
if it scratches topaz, but is scratched by sapphire, it is said to
have a hardness between that of topaz and that of sapphire.
All minerals, including the gem-stone?, have leen tabulated
according to their hardness with reference to ten standard stones,
of which the diamond, the haidest of all known substances,
heads the list. If, for exDmple, a red stone, supposed to be a
ruby, is found to be only about as hard as topaz, it cannot be a
true ruby, but must be a spinel luby, which is quite a dift'erent
thing ; or if it is sufficiently soft to be scratched by rock-crystal,
it is probably a red garnet.

This test is obviously a very rude one in more senses than
one. Not only does everything depend upon the nature of the
scratching pari, whether it is a sharp corner or a curved surface,
and upon the direction in which the scratch is made ; but, to
say the least, the surface of a gem is certainly not improved by
scratching.

The second lest — that of the weightiness — is a really accurate
and scientific one, provided that it be made by means of a
delicate chemical balance. .\ stone which is, bulk for bulk,
three times as heavy as water, is said to have a specific gravity
of 3 ; one such as topaz, which is three and a half times as
heavy as water, is said to have a specific gravity of 3'5. The
ordinary method is to weigh the stone, suspended by a thread,
first in air, and then immersed in water. The dilTerence is
exactly the weight of the water displaced by the stone, and so
the specific gravity is easily found.

The objections to this method are, firstly, that it is too
laborious ; and secondly, that it is not applicable when the stone
is very small, because it is then impossible to weigh it with
accuracy under water. I should not rely upon the specific
gravity of a stone under two carats in weight as determined by
this method. A method which I shall presently describe is
perfectly free from both these ol>jections.

Incredible as it may seem, the estimation of hardness and
the specific gravity are the only attempts at anything like
scientific measurement ever made in the ordinary course of
business applied to stones ; and even then the weightiness is
usually estimated merely by poising the stone in the hand. For
the test they are identified by their colour, their fire or sparkle,
their lustre and their general appearance.

In a lecture delivered to the .Society of Arts in 1881, Prof.
Church drew attention to the necessity of scientific methods (or
this purpose, and has more than once, on subsequent occasions,
reiterated his plea. I propose to dwell more particularly on
improvements which have been introduced since the date of his
lecture, and to indicate how one may, by simple practical tests,
which require little special knowledge, distinguish with cer-
tainly ail gem-stones without in any way injuring them.

Chemical analysis is, by the very nature of the problem, out
of the question, for in order to make an analysis, or to apply
the simplest chemical test, it is necessary to destroy a part of
the material ; and this cannot be done, at any rate in the case of
a cut stone.

We can begin by dismissing the hardness as a characler
which it is really unnecessary to determine, except to identify
diamond or to distinguish a real stone from paste : here, 1
know, I shall earn a rebuke from the orthodox mineralogist
who, in order lo pursue Ihe study of what should be a peaceful
science, arms himself with a knife, and proceeds lo scratch
everything which he comes acros-.

The weapons which I would recommend are of a milder
nature : the microscope, Ihe spectroscope, the goniometer, and
the dichroscope.

.Among Ihe available characters of gems, first and foremost
arc the optical properties ; that is lo say, the appearances seen
when we look at them, or through them, in various ways.

The extent 10 which a ray of light is refr.icled on entering and
leaving a transparent stone, is a characlerislic prn|ierty most use-
ful for delcrminatiun. As everyone knows, a stick half immersed
in water appears bent owing lo Ihe relr.action of light on passing

NO. 1327, VOL. 51]

out of the water ; if it is immersed in a more highly refractive
liquid, it appears more bent.

To ascertain the refractive power of any transparent sub-
stance like glass, a prism-shaped piece is cut from it, and the
extent to which a ray of li^ht is refracted on passing through
the prism is measured by the goniometer, an instrument found
in ever)' physical laboratory.

I have not seen this recommended as a method to be
practically used, because it is commonly supposed that a special
prism must be cut from the stone for the purpose. For the
benefit of those who possess a goniometer, I may say that it is a
method which I constantly apply, and find most useful for
unmounted cut stones. It is always possible to find two of the
facets which form a convenient angle, and, after inking over the
remainder of the stone, to trace the ray passing through these
two facets, and so to measure with absolute accuracy not only
the refraction but the double refraction of the stone ; moreover,
this method is applicable to any stoue, however great its refrac-
tive power.

Another simple plan which can be used by any one, but un-
fortunately only for stones of comparatively low refractive power,
has been invented during the last few years. This delightfully
simple litile instrument, known as the reflectomeler, consists of
a hemispherical glass lens viewed by an eye-piece containing a
graduated scale ; it need only be pressed against the plane
surface of a cut stone previously touched with a drop of liquid
of higher refractive power than the stone itself. On looking
into the eyepiece a shade is seen over half the field of view,
and its edge crosses the scale at a point which gives the exact
refractive index of the stone. The best available liquid is
nionobromo naphthalene, which has a refractive power higher
than that of topaz, and enables one at a glance to distinguish a
cu* topaz or any less brillinnt gem-stone.

Most useful, again, are the so-called interference figures —
the appearances seen on looking through a transparent stone by
means of a polarising microscope, such as is used by every
jjeologist. There is, of course, nothing new in these figures;
ihey are now employed by geologists in the study of rocks, and
even sometimes by those whose business it is to distinguish
precious stones.

Without endeavouring to explain the nature of these figures,
except to say that they are due to the double refraction of the
crystal, it is easy to show that by looking at a stone through a
microscope, one may see something very characteristic.

(The interference figures of several minerals were thrown
upon the screen by means of a projection app.iraius lent by
Prof. Ayrton ; sapphire, tourmaline, and emerald were shown
to give coloured circular rings intersected by a bhack cross ;
sphcne and chrysoberyl, coloured oval rings intersected by a
hyperbola ; and iiu.irtz, coloured circular rings with a black
cross having a tinted centre.)

This beautiful method is not employed neiirly so largely as it
deserves, because most people find it difficult. In order to see
the figure it is necessary lo look through any given crystal in
one certain direction. (The stones ust'd for projection were
plates approprialely cut for the purpose). Now il m.ay happen
that a facetted stone is so cut that to look along the required
direction would be to look through an angular corner ; and
every one knows that it is not possible to look through a
pointed corner, owing to the refraction of the light. For this
reason when an unmounted cut jewel is held under the polaris-
ing microscope, and yieltls no interference figure when turned
about into various positions, it is usually given up .as hopeless.
But obviously we have only to immerse the stone in some
liquid having nearly the same refractive ))ower as itself, in
order to eliminate the dilhculty due to refr.aclion. I find that
if the stone be placed in a small tube filled with oil or glycerine,
and held in various positions, the interference figure can always
be seen. Little more than a year ago, a small facetted stone
of peculiar appearance was sent to me, which had deceived the
experts to whom it had been shown, although agreeing in some
respects with quartz, and was supposed to be a new stone. But
by immersing it in oil in a hollow glass sphere, I was able to
see the characteristic interference figure of quartz. When a
stone has Ihe refraction, Ihe double refraction, the specific
gravity, and the characteristic interference figure of quartz — it
is quartz and nothing else.

Other optical characters of great value are those resulting
from the absorption of the light in its passage through a crystal;

April 4, 1895]

NATURE

547

some of the colours contained in ordinary daylight are more
absorbed than others, and the light emerges more or less
coloured ; in consequence of differences of absorption, some
gem-stones appear differently coloured according to the direction
in which one looks through them. I need not dwell upon this
curious property because the instrument used to observe it is the
one piece of scientific apparatus sometimes, but by no means
generally, used by gem experts — I mean the instrument known as
thedichroscope. (A diagram, kindly lent by Prof. Judd, illustrated
the appearance seen with this instrument.) Far less familiar is the
method of studying the absorption by means of the spectroscope,
although the value of this extremely simple method was pointed
out many years ago by Prof. Church. Every one knows the
colours of the spectrum seen by daylight through a glass prism,
and it is also well known that if light transmitted through
various vapours be appropriately observed through such a prism
by means of the spectroscope, certain black lines are seen in
the spectrum, indicating that the vapour has absorbed light of
a certain colour ; in this way astronomers are able, by merely
looking at the sun and stars, to ascertain many of the elements
which they contain.

But it is not commonly known that a precisely similar effect is
produced by many transparent minerals. It is only necessary
to look through a pocket spectroscope in a bright light at any
transparent mineral containing the rare element didymium, and
certain black bands characteristic of that element are at once
seen in the spectrum.

(A diagram of the spectrum of the phosphorescent light
emitted by ruby when made to glow in the electric discharge in
a vacuum tube, lent by Prof, (irookes, though not a picture
exactly of what is here described, served to illustrate the appear-
ance of the black bands in the spectrum of a red mineral.)

Now, there are two gem-stones which give very characteristic
black bands when looked at through a spectroscope, namely, the
jargoon or jacynth, and the variety of garnet known as alman-
dine, commonly called carbuncle. When a stone, say one set
in a ring, is looked at in this way, and gives the characteristic
spectrum of zircon, it is at once known to be a jargoon without
further trouble.

When one remembers how many pocket spectroscopes are
bought by people who wish to see the rain-band and predict the
weather, it is surprising that it has not also come into use for
the examination of gems.

To pass from optical to other characters, there is a very re-
markable property possessed pre-eminently by one mineral wtiich
has not, so far as I know, been previously recommended as a
practical test.

A crystal of tourmaline while being warmed or cooled be-
comes electrified ; one end becomes charged with positive, the
other end with negative electiicity. The fact has long been
known. But a few years ago an extremely pretty and ingenious
way of showing the electrification was devised by Prof. Kundt.
If a mixture of powdered red lead and sulphur be shaken or
blown through a sieve, the particles become electrified by mutual
friction, and if it then be dusted upon a crystal of tourmaline
which is being warmed or cooled, the positively electrified end
of the crysial attracts the negatively electrified yellow sulphur,
and the other end attracts the positively electrified red lead ;
one end of the crystal becomes red, and the other end yellow ;
and so the difference of electrification is made visible. Now
every crystal of tourmaline behaves in this way, and I find it
perfectly easy to show the properly in an ordinary small jewel,
even when mounted in a setting. .\\\ that is necessary is to
warm the stone, and then, while it is cooling, to dust it with ihe
mixture ; at once one part of the stone becomes red, and another
part yellow.

(.\ facetted stone treated in this way was shown upon the
screen by reflected light.)

The last character which I have to mention is Ihe one to which
I alluded at the beginning, namely, the heaviness or specific
gravity. The use of the balance is, as I said, too laborious ; but
within the last few years an entirely different method has been
introduced.

Cork and wood float in water because, bulk for bulk, they
are lighter; stone and iron sink because, bulk for bulk, they are
heavier than water. But find some substance whose density is
exactly that of water, and it will neither rise nor sink, but will
remain poised in the water like a balloon in mid air.

Several liquids have been discovered which are more than
three and a half times as dense as water, in which, therefore.

amethyst, beryl, and other light stones will actually float. Prof.
Church strongly recommended mercuric and potassium iodide ;
but a still more convenient liquid is now available, namely,
methylene iodide. This liquid has a specific gravity of 33, so
that tourmaline readily floats in it ; further, it is not corrosive
or in any way dangerous, which is more than can be said for
several of the other liquids which have been recommended.

Now it is scarcely possible to prepare a number of liquid^,
each having the specific gravity of one gem-stone, in order to
identify each stone, but methylene iodide is easily diluted by
adding benzene to it ; each drop of benzene added makes the
liquid less dense, and so it may be used to separate tourmaline
and all the lighter gem-stones from each other. Nothing can be
easier or more satisfactory than this method ; no matter how
minute the stone may be, it can be identified by its density in a
few moments. Suppose it be doubtful whether a certain gem
is aquamarine or chrysoberyl, all that is necessary is to place it
in a tube of the liquid, together with a small fragment of true
aquamarine to serve as an index ; if it be a chrysoberyl, which
has a specific gravity of 3'6, it will sink like lead; if it be
an aquamarine, which has a specific gravityof2'7, it will float ;
and if the liquid be then stirred and diluted until the index
fragment is exactly suspended, the gem also will neither float
nor sink, but will remain poised beside it.

The delicacy and simplicity of the method is marvellous ; the
only reason why it has not been more generally adopted is that,
unfortunately, the greater number of gem-stones are heavier
than methylene iodide. What is the use of employing such
liquids whenjthey cannot float jargoon, carbuncle, sapphire,
ruby, chrysoberyl, spinel, topaz, peridote, and diamond, to
mention only those stones whose names are familiar?

But this objection is now entirely removed, thanks to a
discovery made quite recently by the distinguished Dutch
mineralogist, Retgers. He has found a colourless solid com-
pound which melts, at a temperature far below that of boiling
water, to a clear liquidfive times as dense as water ; and there-
fore sufticiently dense to float any known precious stone.

This compound is the double nitrate of silver and thallium,
and it further possesses a most remarkable property ; it will
mix in any desired proportion with warm water, so that by
dilution the specific gravity may be easily reduced. The fused
mass may be reduced in density by adding water drop by drop
so as to suspend in succession jargoon, carbuncle, sapphire and
ruby, chrysoberyl, and spinel.

This wonderful compound should certainly be employed by
all who wish to distinguish gems with ease and certainty.

Let me now remind you how one could apply the methods
which I have been describing, to identify with absolute certainty
some gem-stone. Take, for example, a cut tourmaline.
Dropped into methylene iodide it would just float, and, when the
liquid is diluted, it would remain suspended beside an inde.K
fragment of tourmaline, and no other gem-stone. Examined
with the dichroscope it would show two coloured images, in-
dicating remark.ible diiTerences of absorption characteristic of
tourmaline, and no other mineral ; the absence of absorption
bands, when it is viewed through the spectroscope, would show
that it is neither garnet nor jargoon ; in the polarising
microscope it would show the interference figure of tourmaline.

Even if the stone were mounted in a sttling so that these
tests could not be applied, it could be examined with the
reflectometer, the boundary of the shade would cross the scale
at a point exactly corresponding to the refractive yower of
tourmaline ; and lastly, it could be warmed and dusted with
red lead and sulphur, when the two coloured patches would
betray the electrical properties of tourmaline. There is
enough evidence here to satisfy any one but an English jury
hearing expert witnesses, and everything can be done with-
out inflicting even a scratch upon the stone.

Another mineral character of great value in distinguishing
gem-stones in the rough I have not alluded to, because it can
only be made use of when they are more or less well crystallised ;
I mean the shape of the crystals. (This feature was illustrated
by some very beautiful photographs of gem-stones and other
minerals in their natural state, which were taken from specimens
in the British Museum by the distinguished photographic
expert, Mr. Ilepworth.)

It might be asked, with some show of reason, why should we
require all these scientific tests which I have described, when
the varieties of precious stones are so few in number ? In reality,
however, gem-stones are far more numerous than is commonly

NO.

1327, VOL. 51]

548

NA TURE

[April 4, 1S9:

supposed, alihougb they often pa?s muster under erroneous
names. Tourmaline is sold as ruby, cinnamon stone as jacynlh,
white jirgoon and phenacite as diamond, while green garnets
are universally known in the trade as olivine or perilote.

That the varieties of available gem-stones are not far more
numerous, is due mainly to the prejudice of purchasers, who
ring the changes on diamonds, rubies, sapphires, and emeralds,
and have heard of nothing else ; estimating the stones, as the
public estimates popular actors or authors, not by their real
excellence, but by their names.

In the mineral gallery of the British Museum are many ex-
amples of cut stones which have rarely or never been employed
in jewellery, but should certainly win favour on their own
merits.

One very curious example is a little gem cut from a crystal
of the ordinary tin-stone, the same ore which is worked for tin
in the Cornish mines. This is a stone which, when cut from a
su65ciently transparent crystal, possesses a most beautiful lustre
and colour.

.•\s another example, I may mention a stone which, I suspect
from its appearance, would make a very beautiful gem. It was
sent with some other fragments from the ruby mines of Burmah ;
it is only a single rough fragment, and has completely puzzled
every one to whom I have shown it. By means of the very
tests which I have been describing, and without sacrificing
more than a pin's point of the stone, I have been able to identify
it as the boro-silicate of lime known as Danburite. This
mineral, if it has ever been used in jewellery, which is most
unlikely, has certainly never been rightly named.

{.\ number of facetted stones lent by Mr. Gregory, who has
made many interesting experiments in this direction, were
thrown upon the screen by reflected light ; among these were
several of the less familiar gems, such as tourmaline, chryso-
beryl, phenacite, felspar, andalusite, axinile, spodumenc,
sphene, and idocrase. )

I do not know whether the final impression produced by
what I have said, is that the determination of stones is an easy
or a difficult thing. The impression which I wished to convey,
is that where these scientific lests can be applied, it is an abso-
lutely certain thing ; and where they cannot be applied, there
is no such certainty.

The crystals from which these gems are cut are changeless
and imperishable, their beauty has been enhanced by the art of
man, but they have lost none of their wonderful properties in
the process ; in fact, it is only by utilising these very properties
that the lapidary converts them from dull stones to flashing
jewels, and it is by these properties that we have to recognise
them.

The ruby formed countless ages ago in the heart of Burmah, is
the same thing in all essentials as the ruby formed to-day in a
Paris laboratory.

It is curious to reflect that the diamond which to-day glitters
in a London ball-room, may have adorned the crown of some
Oriental monarch centuries ago — may have been picked from
the shores of an Indian stream in the dawn of civilisation — may
have been the silent witness of the growth and decay of empires
— but by its own unchanging existence has always borne stead-
fast evidence to the everlasting laws of nature.

H. A. MiERS.

THE OBSERVATION OF EARTH-WAVES
A.\'D VIBRATIONS.

'T'HE object of this communication is to call attention to the
•^ apparently high velocity with which motion is transmitted
from an earthquake centre to places distant from it a (juarter
of the earth's circamferencc, and to the importance of instituting
an extended systematic observation of these movements.

During the last few years Dr. li. von Rebeur-f'aschwitz and
other observers in Kuropc have recorded earth movements
which had their origin in Japan or in other distant countries.
Beyond a radius of a fc* hundred miles from thjir origin
these dis'.urbancci arc often too feeble t) be sensible or to be
recorded by ordin.iry seismographs. Their presence is, how-
ever, made known by the us; of specially contrived nearly
horizontal pendulum!, and by Ihcseandother instruments we find
lint they usually have a duration of from ten to thirty minutes,
tl.o jjh now ,ind then lliey la^t one nr two hours. On June 3,

NO. 1327, VOL. 51]

1S93, the writer obtained a record lasting 5 hrs. 24 min. In
Europe what was probably the same disturbance indicated a
movement which continued for about fifteen hours. From ob-
servations hitherto made, it seems extremely likely, as Dr.
E. von KebeurPaschwitz has suggested, that these earth-waves
could be recorded at almost any point upon ihe surface of our
globe, while the phenomena they present are such that it is
probable that their extended study would throw light, not only
upon the manner in which motion is transmitted through the
superficial portions of the earth, but also across its interior.

As illustrative of the results to which these records lead, I
lake those derived from diagrams of several seismographs in
Tokyo, and from that of a long pendulum seismograph at Kocca
di Papa in Italy, which on March 22, 1S94, together wiili many
other instruments in Euiope, exhibited considerable motion.
The origin of the disturbance was off the N.E. coast of Vezo
(Lat. 42 X., Long. 146° E.).

From observations made in Tokyo, distant about 600 miles
from the epicentrum, not only upon the initial disturbance, but
also four after-shocks, it seems that motion was propagated at
an average rate of about 2'3 km. per second. Inasmuch as the
instruments from which these records were obtained, are not
capable of recording movements of small amplitude, prob.
ably this velocity was that of the pronounced vibrations of
the ijuasi-elastic nature characteristic of most earthquakes.
There are reasons for believing that such waves outside an
epifocal area are practically confined to the surface of the earth.
A movement which from the manner in which it slowly afi^ected
ordinary or horizontal pendulum seismographs, had probably a
similar character, travelled from Japan to Italy with a velocity
of from 27 to 3 km. per second, the larger waves travelling at
the slower rale.

Preceding these decided motions, minute tremors were ob-
served, which, if they originated at the epicentrum and
travelled on the surface of the earth, must have done so at a
rate of 115 km. per second, while if they were created by the
transformation of the energy of the partially elastic undulations
as they passed from medium to medium, then their velocity of
propagation inu5l have been still more abnormal. If it is
assumed that they reached Italy by direct radiation through the
earth, or that in consequence of refraction they followed cur-
vilincir paths, the observations indicate a velocity of 9 or 10
km. per second.

Considering the influence of gravity upon the propagation of
surface undulations, the observed velocities may possibly be a
little lower than what might have been expected. The minute
tremors, hovever, seem to have a velocity which is roughly
twice that for a condensational raref.actional wave in glass.

Observations upon other earthquakes, although none of them
can claim any great degree of accuracy, point to the same
general results.

At present, the diversity of instruments employed in Europr.
and the various degrees of sensibility given to the few iiistru
ments which are approximately similar, apparently results in the
recording of ditTerent phases of motion, and it is not likely
that our knowledge will be increased or made more accurate
until there is greater uniformity in the methods ol observation.
Now to determine whether the disturbances created by large
earthquakes are propagated to distant localitic> in the manner
suggested, much might .be learned by establishing twelve or
fourteen similar instruments at an equal number of selected
stations round the northern hemisphere. It is yet premature
to indicate the class of instruments to be employed, but if
their chief function is to record the time of arrival and the
dilTercnt phases of these wide-spreading movements, it is the
writer's experience that many difticuliies may be avoided in
installation, adjustment and management, by using a type that
is not too sensitive to extremely minute changes ol level, such
as accompany fluctuations in temperature and changes in
atmospheric conditions. All of them should admit of ad-
justment to a similar degree of sensibility, and so lar as possible
be ailached to similar foundations in localities or places where
Ihe efl'ecls of tremor storms, which often eclipse the eflfects due
to earthquakes, are not likely to be pronounced. Photographic
surfaces on which records are received, should move at a rate
of iiol lea than two inches per hour, which will enable an
observer to determine time intervals to within 30 seconds.

It would seem advisable that the first attempt to inake a
seismic survey of the world should be tentative. Having ob-

April 4, 1^595]

NA TURE

519

tained the co-operation of observers in selected localities, each
of these should be furnished with a similar instrument, and if
possible receive personal instruction as to its installation and
working. If this is done, then an inexpensive type of apparatus
may be employed, which in an ordinary foundation will yield
results not much inferior to those obtained from more elaborate
arrangements, which subsequently it may be thought desirable
to establish.

Althou};h it may only be possible to minimise the effects of
tremors, the records of these over extended areas may perhaps
present new features. Other movements which are likely to
be noted, but which will not influence the recording of move-
ments resulting from distant earthquake;, will be diurnal and
other periodic dis| lacements of the pendulums. The records
of these, together with those of local earthquakes, could hardly
fail in adding to the knowledge we possess about earth
movements.

The principal object of the proposal made in the foregoing
remarks, is to determine the velocity with which earthquake
motion is propagated over the surface of the earth, and po.-sibly
through its interior. If it is established that vibratory motion
is transmitted with a measurable velocity through the earth, it
will be difficult tn overestimate the value of the knowledge
we shall have gained. The rigid scrutiny of the records
bearing on this latter point have to be left to European
observers.

At present the « riier is engaged in drawing up a report upon
Ihe state of our knowledge respecting the velocity with which
earth vibrations and waves are transmitted through rock and
earth, and in making experiments to determine a form of simple
instrument which shall be not only sensible to slight changes
of level, but which is also capable of recording vibrations o(
small amplitude.

Since writing the foregoing, which was printed for circulation
amongst a few of my friends interested in this branch of earth
physics, I have received NATt;RE o( Decetnber 27, 1894, in
which, on p. 208, Dr. E. von Rebeur-Paschwitz gives a description
of the remarkable disturbance of June 3, 1893, to which I have
already briefly referred. In )uly of that year I «ent photographs
of this record to various acquaintances in Europe. One of
these, together with a description of the same, because it was
illustrative of a great numt^er of unfelt earthquakes which I had
recorded, was sent wi'h the fourteenth report to the Briiish
Association on seismological work in Japan during 1893-1S94.
This report is, I believe, now in the press. The object in calling
attention to this matter is to show that thisdisturbanc, wherever
it originated, was also pronounced at places far distant from
Sirassburp, Nicolaiew and Birmingham.

Mr. C. Davison, who writes the introduction to the description
of the European records of this earthquake, makes a brief
reference to the Hesirahility of having a lew »-ell-choser stations
in various paits of the world where earth ])uIsalions might be
recorded — a matter on which I have had considerable corre-
spondence with my friend Dr. E. von Rebeur-P.ischwitz. At
present Mr. Davison considers that Europe is fairly well
provided with instruments. Instruments are certainly fairly
numerous, but at the same time in many instances ihey vary in
their sensibilities and also in their objects. Judging from the
report of the Committee on Earth Tremors to the British
Association in 1S93. i>. 294, it would stem that the instruments
in Birmingham and Edinburgh are arranged to lie unaffected by
rapid tremors, and register "slow earth lilts only," while the
tromomet' rs of Italy are, I presume, constructed to record what
this name inplies. Whether they are able to record " elastic"
tremors is a dehatatile matter. A very gnod illustration of
what the heterogeneitv of the instruments at present empfiyed
in Europe leads to, is given by Mr. Davison in the records of
two earthqtiakec, contained in the report of the above-mentioned
Committee for 1894, which may have had velocities of propaga-
tion varying between I and 12 km. per second, according to the
type of instrument from which records were ob'aned. The
apparent explanation of these anomalies is that different
instruments have lecorded dilTerent phases of motion, and for
this reason I have been led to say that it is not likely ihit our
present knowle'lge will be increased until there is greater
uniformity in thr methods of observation.

Mr. Davison's remark that "in Japan Prof. Milne's
tromometer (as described in British Association Report, 1892,

pp. 207-209) leaves little to be desired," requires qualification.
As a " tremor " recorder it is excellent.but even as such I have im-
proved it by reducing its length to 30 mm. and its total weight to
0-39 grms. Unfortunately however, because it is a tremor re-
corder, its movements are such that even on a photographic film
only one metre distant, it may during a severe "tremor storm "
give a trace which appears as a band two inches in breadth, which
eclipses any effects due to dis'ant earthquakes, for the recording
of which it is therefore useless. At various times I have
experimented with at least a dozen of such contrivances, which
from the nature of their construction have necessarily short
periods of vibration, and are therefore not sensible to slight
lilting. Although I condemn these instruments for the record-
ing of distant earthcjuakes, I must admit that I am indebted to
a pair of them for having first made visible to me the diurnal
wave.

In the Seismological Journal, vol. iii. p. 60, a sketch is given
of a horizontal pendulum, such as I have used to record the
daily wave and unfelt earthquakes since November 1893. One
of these, which has a boom 5 feet in length, has usually a
period of about 50 or 55 seconds. Altogether I have six sets
of such apparatus with photographic recording surfaces,
together with one or two others, which are read once per day.

These have been installed at and given records from eighteen
localities — in caves, in the solid rock, in an underground
chamber, and on substantial columns rising from the natural soil.
Although these instruments are exceedingly bad forms for
tromometers, by these experiments — each of which continued
over several months, during which time continuous records were
obtained— much was learned about the localities where "tremor"
effects might be avoided.

To solve the problem under consideration it does not seem
necessary to have an instrument sensible to less tilting than I ',
and it is certainly undesirable to have one sensible to the
phenomena called earth tremors or microseismic disturbances,
which appear to have the character of earth pulsations. What
is required is an instrument which is susceptible to the tilting
produced by the undulatory slow travelling quasi-elastic dis-
turbances of an earthquake, and at the same time is sensible to
Ihe minute, and possibly truly elastic vibrations which, both in
Japan and Europe, outrace the moie pronounced movements.
The first object, and to some extent the second, is certainly
attained by many instruments in Europe. From the records
given by the long pendulum of Dr. Agamennone, of which I
have not ha<l an opportunity to see a lull description or draw-
ings, I take it that for the preliminary vibrations, the pendulum
acts as a steady point, relatively to which the movements are
magnified by means of a pointer arranged like that of a seis-
mograph. The larger movements, which have periods of about
16 seconds, may he due to the slow heeling over of the pen-
dulum following the motion of the supporting to«er. About
these latter movements we already know a great deal, and their
velocities of propagation, as determined by the most accurate
methods in Japan, do not materially differ from the rate at
which the same disturbances continue on their journey to
Europe.

What we most require is an investigation of the velocities of
propagation of the elastic movements which apparently go from
Japan 10 Europe in 15 or 20 minutes.

If such phenomena exist, and if the European records are
correct, their existence is a reality, the instruments to record
their repetition must be sensible to small but rapid vibrations ;
and for the results to be comparable, these instruments must not
only be similar in construction, but they must be similarly
adjusted and similarly installed.

Within a few days the writer will have completed two instru-
ments differing only in their size, which may be described as
conical pendulum sei-mographs in which the multiplication
relatively to their centres of oscillation will be adjustable from
about 20 to 40. The registration will as usual be photographic.
It is hoped ihat because the multiplication is large, and because
everything is as light as possible, the preliminary tremors
(elastic vibrations) may be recorded; while because the booms
are long, it is not unlikely that the sensitiveness to tilling will
be sufficient to record the slower waves. They will be tested
upon a foundation the diurnal tilling of which is known, and
where it is also known that tremors (earth pulsations) are
seldom met with.

John Milne.

NO. 1327, VOL. 5 1]

550

NA TURE

[April 4, 1895

SOCIETIES AND ACADE\fIES.

London.

Royal Society, March 21. — "A possible Explanation of
the two fold Spectra of Oxygen and Nitrogen." By E. C.
C. Baly.

The two spectra of oxygen are shown to be of a different
nature. They behave diffi?renily, and reasons are given for
their being in all probability the spectra of different gases.
They may either be two spectra produced by different vibrations
of the oxygen molecule, or they may be the spectra of two
different modifications of oxygen, or the spectra of two distinct
gases resulting fiom a dissociation of oxygen, a combination of
which is called oxygen.

It appeared worth while to undertake experiments with a
view of testing the last of these. Oxygen was sparked in an
apparatus similar to that used by Prol. J. J. Thomson in his
experiments on the elecirolysis of stea^n. Hollow plaiinum
electrodes were used, each one of which was connected with a
Sprergel irercury pump. In the first experiments, the distance
between the electrodes was 35 mm., and the highest pressure
compaiible with the appearance of the two spectra was made
the starting point of the experiments. In these first experi-
ments it was 3S0 mm. The density of the oxygen before spark-
ing was deermined, and taken as a test of its purity. The
fractions obtained from the anorie and cathode were weighed,
and the results are given. They (ill )w the lines ol J. J.
Thomson's results, inasmuch as with long sparks a lighter
fraction was obtained at the cathode, and with short sparks a
heavier fraction. The fractions from the anode were not so
definite as from the cathode, though ihe difference was in the
right direction. The probable maximum eiror of weighing
was o 0001 gram. This meant exactly one in the second
decimal place of the density obtained. The general accuracy
of the results may be gauged from the densities of unsparked
oxygen obtained.

Density of Density of Density of

cathode fraction oxyg-n cathode fraction

with long sparks. unsi arked. with short sparks.

15 78 ... 15 88 ... 16 00

15 79 ... 15 87 ... I6-OI

1580 ... iS'Sg ... 1602

1579 ... 15 88 ... 16 04

1588 ... i6o5

16 05

Mean of results of other observers ~ 15 887.

Density of cathode fraction from oxygen, previously for three
days fractionated with ihort sparks, 1575.
The experiments are still in progress.

Physical Society, March 22. — Mr. R. T. Glazebrook,
F. R. .S., in the chair. — On the objective realiiy of combination
tones, by Prof. A. \V. Riickcr and Mr. E. Eilser. The question
as to the ohjeciive or subje.tive nature of combination tones
has excited much keen controversy, and iheau hors have devised
some experiments to elucidate this point. These experiments,
some ol which were exhibited before the Society, show that
noder certain conditions diHerence and summation tones are
produced which are capable o' disturbing resonating bodies.
As resonator they have, in ihe first instance, employed a tuning-
fork. A piece of thin wood, about 5 in. square, is attached to
one of the prongs of this fork, «hile a silvered glass mirror is
attached to the other, and the pitth of the fork is very ac-
curately adjusted to sixty-four complete vibrations per second.
lo Older to detect any movement due to resonance set up in ihis
fork, the mirror earned by the prong forms pait of a system of
mirrors for protlucing Miclu Ivm's interference bands. By ihis
means a movement of the iiron^s cif the fork of 1/8.^1,000 of an
inch (half a wavelcngih ol linht; is shown by the dis.ippearancc
of the interference binds. As a source of sound a siren w.is
employed, this beii'g one of the instruments which Ilelmhullz
recommend! as giving the best results. The pitch of the nolcs
given by the siren was adjusted by noting the disappearance of
the beats produced by one ol the notes with a bowed fork, or
by a .stroboicopic method. A la'gc wooden cone, placed be-
tween the siren and the resinating fork, served In concentrate
the sound on the wooden disc atiachcd lo ths latter. The sen-
sitivcnets of the arrangement is such, that when a large Kcienig
standard fr.rk, giving sixty-four vilir^tions per second, is struck
so lightly that an observer, with his ear close to the fork, cannot
detect the fundamental note, the bands instantly disappear.

NO. 1327, VOL. 51]

The apparatus, however, is unafTecled by any other note, except
one of sixty-four vibrations per second. A number of experi-
ments have been made, using various rows of holes on the siren,
and in every case when the summation or difference tone corre-
sponded to sixty-four vibrations per second, the interference
bands vanished, showing that under the conditions of the experi-
ment these tones have an objective existence. An experiment has
also been made to determine whether Kiienig's lower beat tone
when the interval is greater than an octave is objective. In this
case, however, the authors entirely failed to get any evidence of
such an objective existence. A numberof experiments have been
made with a view to elucidating the cause of the pioduciion of
the summation tone, which tend to show that it is not the
difference tone of the parlials of the fundamental notes. In
addition to using a luning-lork to detect the combination tones,
the authors have made use of an instrument originally devised
by Lord Rayleigh. A light mirror is suspended t>y means of a
fine quartz fibre, and hangs in the neck of a resonator, tuned to
the given note, and when at rest is inclined at 45° to the axis
of the resonator. Under these circumstances, when the resonator
responds the mirror tends to turn and set itself at right angles
10 the direcion of mo'ion of the air in the resonator. The
results obtained with this instrument are in complete accord
with those obtained by ilie first method. Up to the present the
authors have failed to obtain any evidence of the otijeciive reality
of the combination tones produced by organ-pipes and tuning-
forks (see p. 474). The discussion on this paper was postponed
till after the reading of the next paper. — Some acoustical experi-
ments, by Dr. C. V. Burton. (1) On the subjective lowering
of pi ch of a note. The author has noticed that if a tuning-
fork, mounted on a resonator, is strongly bowed, then if the ear
is placed near the opening of the resonator the pitch of the note
heard appears lower than when the fork is bowed very gently
or is held at some distance. This subjective lowering of pitch
is most marked with forks of low pitch ; and in the case of a
fork giving a note of 12S complete vibraiions per second,
amounts to about a minor third. The author suggests an ex-
planation depending on the supposition that the basilar
membr.ine of the ear behaves as if it consisted of a number of
stretched strings of various lengths, e.ach resounding to a given
note ; and that the appreciation of the pitch of a note
depends on the localisation of the part of the basilar
membrane which resounds most strongly. Further, he
shows that in the case of a stretched string, for finite
displacements, the siring which most strongly resounds
to any noie will have a " natural " period longer than the
period of the di-lurbance; the greater the distuibince the longer
will be the natural period of the strings most strongly affected.
Hence when the intensity of a note increases, the tract of the
basilar membrane most strongly affecled is displaced in the
direction «hich corresponds to the percefition of lower notes.
(2) Objeciivedcm nstra'ion of com'iination tones. Whire two
organ-pipes are sounded and alternately separ.ated ami brought
close together, an observer, at some distance, hears the did'erence
tone much more clearly when the pipes are close together than
he does when they are separate. As the position of the pipes
with reference to his ear does not appreciably change, the change
in the intensity of the combination tone indicates that it has a
real objective exis'ence. The author mentioned that ho had
sounded his two pipes, which give a diflereiice tone of 64 vibra-
tions per second, lefore the collector of Piof. Riiiker and Mr.
Edser's app.iratus, but without obtaining any nioti n of the
interference bands, and that he was therefore less conlident of
the correctness of his deductions than he h.ad been before. Mr.
Ed-er menliored thai Dr. Burton had suggested an cx|.|Anation
of the production of objective tones in the case of the siicn, which
depends on the production of the tones in the wind-chest of
the instrument itself when two rows of holes are simulla-
neouly opened. They had made an experiment which seemed
lo show ihat the above explanation was incorreci, for on con-
necting together the wind-ches's of two sirens, fixed on Ihe same
spndle, by means of a .short length ol wide me'al tubing, no
effect was obseivcd on ihe bands «hen Ihe two noes were
produced on different instruments having what was p.aciically
a common win l-chesl. — Prof. Everett (communicaierl) said be
considered the experimcnis described in the paper proved con-
clusively the objec'ivc existence of the suinnianon tones as
dis inguished from siippo cd beat tones. He had lately been
invesligalin.; Ihe pilch nf ihe loudest combination tone obtained
when two notes having fiequencies as 3 to 5 are sounded. Is

April 4, 1895J

NATURE

551

the frequency of this tone 2, i.e. the first difference tone, or is
it I, which corresponds to the first term of the Fourier series
for the periodic disiurbance ? In tlie chords 2 to 3, 3 to 4, 4
to S, &c., the difference of the intfgers lieing unity, the first
difference tone is identical with the first Fourier tone. When
the difference of the two integers which express the chord is
not unily, then the writer considers that experiments he has
made with strings and pipes, show that the first Fourier term
is usually the only combination tone that is audible. Prof. S,
P. Thompson considered that care should be taken to define
what we mean by the subjective or objective existence of a note.
There are two very delicate methods which have already been
employed for detecting the existence of a given note in the air.
(l) The formation of ripples on a soap-film stretched over the
opening of a resonator tuned to the rttjuircd pilch (.Sedley
Taylor) ; (2) the sounds produced in a telephone connected to
a microphone placed on a thin elastic membrane slretched over
the neck of the resonator (Lummer). It was very important to
limit our acceptance of the demonstration of the objectivity of
combination tones, given by the authors of the paper, to the
case actually proved, i.e. to tones produced by the polyphonic
siren. It did not necessarily follow that if pure tones produced
by tuning-forks were used, the srime results would be
obtained. A number of experiments had been made
by Zanledeschi in 1S57, in which two notes were
sounded, and skilled musicians were asked to record
their impression of the third tone present. In 75 per cert, cf
the cases the note recorded was the difference tone ; in the
remaining25percenl.it corresponded to Kiitnig's b'at tone.
Kbenig himself had never heard the summation tone in the case
of lightly-bowed forks. Voigtin a theoretical paper has shown
that if there ,-ire two disturbances whcse mean kinetic energy
difftr, the Ilelmhollz tones will be produced; but that if the
mean kinetic energy of the two disturbances are equal, the
Helmholtz effects soon die out, and you get beat tones or beats.
He (Prof Thompson) considered that Dr. Burton had allowed
his perception of tone to be governed by the quality of the role,
and that the apparent lowering of pitch was due to ihe variation
in the intensity of the overtones present. In reply to Prof.
Thompson, Dr. liurton said he did not merely perceive a lower-
ing of pitch, but he was able to estimate the change in pitch,
and say at what instant, as the vibrations of the fork died out,
Ibe lowering amounted to a lone or half a tone, &c. Mr. Boys
said he found that by careful atlemlon he could apparently per-
suade himself that the note in Dr. Burton's experiment was
lowered or raised in pitch, or that it remained unaltered. A
similar effect in the case of the eye could be obtained with a
stereoscopic picture. The Chairman considered that, while
Helmholtz' explanation of the pioduclion of combinalion
tones might be real, it did not follow that this explanation gave
the sole cause of their formation. In particular, Helmholtz
does not explain w by the tones should only be produced by some
sources of sound. Prof Riicker, in his reply, said he did not
deny the existence of Koenig's beat tones ; in fact, he had heard
them. Tliey did not lay much stress on Ihe negative result of
the experiment they had made to test the objective existence of
these heat tones.

Zoological Society, March ly. — Sir W. H. Fluwer,
K.C.B., F.R.S., Pre.-ident, in the chair.— Lt.-Col. H. H.
Godwin-Austen, F.R.S., presented a paper on behalf of Mr.
Walter E. Collinge, and himself, " 'in the Structure and Affi-
nities of some new Species of Molluscs from Borneo." Three
new species were described, viz. Daniayattita ^mithij lilicropar-
mariou pclloiicrai, and M. limrolhi. Iictails were given of
their structure and com|-arisons instituted with other members
of the genera and allied Indian genera. One of the most in-
teresting features, perhaps, was the similarity they show an.ito-
mically to shell-bearing molluscs of Borneo. That these slug-
like forms of Borneo have the same close relalionsh'p to the
shell-bearing mollusca among whom ihcy are now found living,
as the Indian forms bear to Macrochlawys and allied shell-
bearing genera, there can be little doubt, and any true attempt
at classification must be based on these lines, and would place
a wide gulf between Cirasia and Austeiiia on the one side, and
Parmaricn and Rlicrof-armarion on the other. — Mr. F. E.
Beddard, F.R.S., read a preliminary account of new species of
earthworms belonging to the Hamburg Museum. These worms
belong cbielly to ihe genera A(anll:oJiiliis and Alicroscolex,
and had been collected in South America. — Prof. F. Jeflfrey
Bell communicated, on behalf of I'rof Alphonse Milne-

NO. 1327, VOL. 51]

Edwards, Jardin des Plantes, Paris, the description of a new
species of crab of the genus llyailentis, obtained near the
Straits of Magellan during the Challenger Expedition, and pro-
posed to be described as //. comobrinus. — Dr. A. G. Butler
gave an account of two collections of Lepidoplera received by
the British Museum. One from Zomba, made by Mr. J.
McClounie, remarkable for Ihe number of specimens of the fine
Butterfly genus Chara.xrs it contained. The other made at
Fwambo, Lake Tanganyika, by Mr. .Vlexander Carson, in-
teresting as including rot only rare species previously only
received from Zomba and Lake Mweru, but several novelties,
the finest of which was Junonia pavonina, a new form allied
to /. arlaxia. — .Mr. P. Chalmers Mitchell read a paper in which
he gave a description of the provinlricular crypts he had found
in a specimen of the African Tantalus {Pseudotaiitaius il>is)
recently livirg in Ihe Society's Gardens.

Entomological Society, March 20. — Piof. Raphael
MeUlola, F.R.S., President, in the chair. — Mr. H. St. John
Donisthorpe exhibited a living female of Dytiicus iiiarginaiis,
with elytra resembling those of the male insect. Dr. Sharp,
F.R.S., said he had seen this form before, but that it was very
rare in ihis country, though abundant in some other parts of the
paljearctic region. Prof. Stewart asked if the genitalia had been
examined. Mr. Champion stated ihat Mr. J. J. Walker had
collected several females of an allied species (Dyliscus circum-
/le.xiis) at Gibraltar with elyira resembling those of the male. —
Dr. Sharp exhibited specimens of Hrenlhiis aitc/iorago, from
Mexico, showing extreme variation in size. He remarked that
the males varied (rom loi mill, in length 1051 mill.; the female
from 9^ mill. 1027 mill. In the male the width varied from ij
mill, to 4 mill. The length therefore varied from about 5 to i,
and the width from 3 to i in the male. — Mr. Blandford com-
mented on the difficulty of mounting minute Lepidoplera, Dip-
tera, Neuroptera, &c., and exhibited samples of stripsof material
which he had found most suitable for the purpose of staging
minute insects. He said his attention had been called to this
method of mounting by Ihe receipt of specimens from Dr. Fri£,
of Prague. On examination of the material he found it to be a
fungus, J'otyfoi us leiiilitiiis. He stated ihat Lord Walsingham
had expressed his satisfaction wilh this material, and had sent
him specimens, similarly mounted, from /eller's collection.
Mr. McLachlan, F. R.S., remarked that he thought the material
exhibited preferable to artichoke pith, which had been used for
a similar purpose. — Mr. Goss exhibited a specici of a Mantid,
J'iaidocreobotra Wahlbergi, Slal, received from Captain Mont-
gomery, J. P., of Mid-Ilovu, Natal. — Mr. Frederick A. A.
Skuse communicated a paper, entitled " On a colour variety of
Heteronymfhtt metope. Fab., from New Soulh Wales," and
sent coloured drawings of the typical form and the variety for
exhibition. — Mr. Oswald H. Latter read a paper, entitled
" Further notes on the secretion of polassium hydroxide by
Dicranura viniila (imago) and similar phenomena in other
I.epirioptera." The paper was illustrated by the oxyliydrogen
lantern. Prof. Meldola congratulated Mr. Latter on the
thorough way in which he had worked out his experiment,
and said that in view of the small quantity of material at his
disposal, the concordance in the results was remarkable. He
added that Mr. Latter had, for the first time, proved the secre-
tion of free potassium hydroxide in the animal kingdom. Mr.
Blandford, Mr. Merrifield, and Dr. Dixey continued Ihe dis-
cussion.— Mr. Merrifield read a paper, entitled "The results
of experiments made last season on Vanessa C-album and
Limenitis Sibylla." This was illustrated by an exhibition of
specimens of /,. sibylla, and a long series of V. Calbiim, to show
the effects of temperature in producing abnormal forms. Dr.
Dixey said that many of the forms of V. Calbum exhibited re-
minded him of /'. Caurcum, a Chinese species, which he be-
lieved to be one of Ihe oldest forms of the genus. He thought that
much of the variation shown in this series of specimens was
due to al.ivism, and was not directly attributable to the eflfect
of temperature. Mr. Barrett said he was interested to find that
one of the forced forms of /.. sibylla was similar to a specimen
he had seen which had emerged from the pupa during a thunder-
storm. In ccnnection with Mr. Meirifield's paper, Mr. F. W.
Frohawk exhibited a scries of 200 specimens of V. Calbum,
bred fiem one female token in Heicfordshire, in April 1894.
The series consisted of 105 malts and 95 females, and included
41 specimens cf the light foim, and 159 of the dark form.
Piof. Meldola, in proposing a vote of thanks to Mr. Merrifield,
Dr. Dixey, and Mr. Frohawk, said that he was glad to think

55^

NAl URh

[Al'KIL 4, 1895

that the subject of seasonal ilimorphism, which had been first
investigatfd systematically by Weismann, wa'; receiving so
much aiteniion in this country. He was of opinion that the
result? hitherto arrived at were quite in harmony with Weis-
mann's theory of reversion to the glacial form, and all the evi-
dence recently accumulated by the excellent observations of Mr.
Merrifi' Id and others went to confirm this view as opposed to
that of the direct action of temperature as a modifying influence.

Mathematical Society, March 14. — Major P. A. Mac-
Mahon, R.A., F.R.S., President, in the chair. — The President
announced that he had written letters of condolence to Lady
Cockle and Mrs. Cayley, and had received their acknowledg-
ments of receipt of the same, which he communicated to the
meeting. — Prof. Hill, F.R.S., communicated a paper, by Mr. F.
H. Jackson, entitled "Certain n Functions," and the President
(Mr. \. B. Kempe, F.R.S., in the chair) read a paper on the
perpetuant invariants of binary quantics. — Lieut. -Col. Allan
Cunningham, R.E., gave a proof lh.al 2'''"-l is divisible by
7487. — The President read a letter from the Rev. T. C.
Simmons, announcing what the writer believed to be a "new
theorem in Probability."

Paris.

Academy of Sciences, March

■ M. Marey in the

chair. — On the theory of surfaces and of algebraical groups, by
M. Emile Pic.ird. — New researches by Prof. Ramsay on argon
and on Helium, communicated by M. Berthelot. A letter from
Prof. Ramsay was read describing the spectrum of argon ob-
tained from cleveite and the discovery of Helium. — Remarks on
the spectra of argon and of the aurora horealis, by M.
Berthelot. During the author's recent experiments on the con-
densation of argon with benz-ne vapour under the influence of
the silent di-chatgc, a magnificent greenish-yelliiw fluorescence
was observed. Its spectrum consisted of a series of lines and
remark,ible bands. So far as the experimental conditions
allowed of comparison, this spectrum recalled that of the
aurora borealis. It is suggested that thii phenomenon may
possibly be due to the formation of some fluorescent combination
of argon in the upper regions of the atmosphere under electrical
influence. — Researches on the metals of Cerite, by M. P.
Schiltzenberger. The preparation of cerium sulphate in a state
of such purity as to admit of accurate determinations ol the
atomic weight of cerium is described. The value 13945 '* °'''
tained for this constant by a special process of estimating the
sulphuric acid in this sulphate. It is shown that other methods
of obtaining the atomic weight give unreliable results. Taking
various fractions of the sulphate on recrystalli^ation, the later
fractions give a much less value for the atomic weight of
cerium than the earlier ones. — Observations "f Charloi'^'
planet BU, made at Toulouse observatorv, by MM. H. Bail-
land and Rossard. ^Observations of \V.)lfs planet BT (March
16, 1895), made at Uesanijon observatory, by M. H. Peit — A
gen'ral property of axoids, by M. A. Mannheim. — On lines of
curvature, by M. Thomas Craig. — On ttie theory of equations
to'the deiived parlials, by M. Wladimir de Tannenberg. — On
linear equations to the derived parlials, by M. Kmile Borel. —
On the movimcnt of pmjectilei in the air, by M. Clupel. A
scries of four equaticmsare given which supply a complete solu-
tion to the ballistic problem for speeds ranging between 300 in.
and I loom. — On the extension to magnesia of a method of
syn'hesising fluorides and silicates, by M. A. Duhoin. The
compounds MgKj. KF, ,MgF2. 2KF, and MgO . K5O. 3SiO„
are described and their optical and chemical properties given. —
On a new method for the preparation of chlornplatinuus acid
and its sails, by M. Leon Pigeon. Reduction of chloro-
plalinic acid in accordance with the equation,

BaPiCle + BaS,0„ -H H\^0 - lI.PlCI, -I- 2HCI -4- 2 BaSO^,

is employed. Following the method given in detail, the yield
i» almost theoretical — Heat of formation of calcium aceiyUde, by
M. dc Forcrand. The heat c,f formation of .sulid CjCa Irom
diamond and «olid Ca is — 7'25(Jal,, substituting am rijhous
carbon it is -0'6s Cal., for gascms carbon it is +76 95 Cil.
— Action of oriho-amidobrnz ic acid on ben^nquinone, by MM.
]. Ville and Ch A»lic. — Alterations in saccharine matters
during 'he ccminalion of barley, by M. P, Petit. The con-
clusions arc drawn : (1) There is a rcl.rlion between the quan-
Ii'ie« o( reducing sugars and of sacchato'te ex sling in barley
duiing its germintti'in. (2) The formition of siccharose com-
mences even during lhcdam|<ing, whereas icHuLin^ sugars re-
main nearly constant during the same period. (3) The variation

NO. 1327, VOL. 51]

of reducing power represents the activity of respiration, —
Chemical process for the purificalion of water, by MM. F.
Bordas and Ch. Girard. Calcium permanganate is employed
to oxidi-;e the organic matters, and the excess of this salt is re-
moved by treatment with lower oxides of manganese. The
treatment recommended removes organic matter also by physi-
cally precipita'ing it from the water, which, after treatment,
contains no micro-organisms, and very little calcium carbonate.
— » >n the wheat produced on a saliferous soil in Algeria, by
MM. Berthauli and Crochetelle, — On the abnormal fronds of
ferns by M. Ernest Olivier. — Origin and division of granular
nuclei in large sarcomatous cells, by MM. O Van der Stricht
and P. Walton. — A note, by M. Delaurier, concerning an easy
method of obtaining a perfect vacuum without mechanism,
deals with the production of a vacuum by absorption, as with
oxygen and iron at a red heat.

BOOKS, PAMPHLETS, and SERIALS RECEIVED.

Books.— Birds, Beasts, and Fishes of the Norfolk Broadland : P. H.
Emerson (Null). — Balisiiquc des Nouvelles Pnudres : K. Vallier (Paris.
Gauthier-Villars) — La Thtiorie dcs Proccdcs Photogmphiques : A. dc la
Baume PluvincI (P.iris, Gauthier-Villars).— La Oistillati.m : E. Sorel
(I'aris, Gauthier-Villars). — Dissections Illustrated: C. G Brodie, Part ^
(Whittaker). — Methodisches Lchrbuch der Elementar ^L1thcmatik : Dr. G.
Holzmiillcr, Driticr Tcil (Leipzia:, Teubner). — A Primer of Evolution; E.
Clodd (Longmans). — Geometrical Conies; F. S. Macaulay (Cambridge
University Press). — Standard Diction.iry. Vol. 2 (Funk and Wagnalls). —
Outlines of Zoology : J. A. Thom-^on, 2nd edition (Pentland).— The Book
of the Dead. The Papyrus of Ani in the British Museum : Dr. E. A. W,
Budge (liriiish Museum).

Pamphlets. - Report of the Meteorological Council to the Royal
Stcieiy for the Year ending March 31, 1S94 (Eyre and Spottiswoodc). —
Sionyhurst College observatory. Results of Meteorological .ind Majr*
netical Observations, 1894: Rev. W. Sidgrcaves (Clithcroc). — i8lh Kcpmt
of the State Eniomolopisi on the Noxious and Beneficial Insects of tlu
Slate of Illinois (Springfield, 1 II ).

Serials— -CasseU's Magaaine, April (Cassell). — Chambers's Journal,
April (Chambrrs). — Century Magazine, April (Unwln)— Natural Science,
April (kail). — Zcitschrifi (iir Wissenschaftliche Zoologte. lix. Band. 1 Heft
(Leipzig. Engclniann). — Gazictta Chimica Italiann, 1895, Fa»c. 2(Rom.i).—
Humanitarian. April (Hutchinson). — Contemporary Review, Ap'il(Isbister).
— \ati inal Review. April (Arnold). — Fi rtiiighlly Review, April (Chapman).
Bulletin dc la Acad<imic Royale dcs Sciences, &c., de Belgique, tome 29,
No. 2 (Bruxelles). Geographical Journal, April'tStftiiford). —Journal of
the Royal Agricultural Society of England (third series), Vol. vi. Part 1
(Muriay).

CONTENTS. p

Verworn on General Physiology. l>y Dr. M. Foster,

F.R.S

Nernst's Theoretical Chemistry. By M. M. Patti-

son Muir

Our Book Shelf:—

Il.iyward : "Bird Notes" • . . . .

Gurncy : " Ca'alogue of the Birds of Prey {Acciptrcs

and Strigei)" : • •

Beazley : " Prince Henry the Navigator." — W. . .
Ziwet ; " An Elementary Treatise on Theoretical

Mech.inics. " — G

Letters to the Editor:—

Dtstruclion of the Seismological Observatory at

Tcikio, Japan. — Prof. John W. Judd, F.R.S. .

On Mersenncr's Niimhers. — Lieut.-Colonel Allan

Cunningham, R.E

Tan-SpDis over Dugs' Eyes. — S. E. Peal ; Dr.

Alfred R. Wallace, F.R.S. . .

The Age of the Earth. By Prof. W. J. Sollas,

F.R.S. .....

The Anniversary of the Chemical Society ....

Sir Henry Creswicke Rawlinson, Bart

Notes

Our Astronomical Column : —

C-mct e 1S94 (Swifi)

\ I'o^-iiih- Ni-vv S.iiellile of Neptune

Prof Mendelecff on Argon

Teirchtrial Helium (?)

IsMlation of Free Hydrazine, NjHj. lly A. E.

Tutton

Science in the Magazines

Preciou- Stones, and How to Distinguish them. l!y

H. A Mieis

The Observation of Earth-waves and Vibrations.

r,y Piol John Milne, F R.S

Societie ano Acadsn.ies

BookH, Pamphlets, and Serials Received . . . .

529

530

53-

532
532

53.i

533

53.)

533

533

536
537

542
542
543
S«

544
545

545

54S
550
552

NA TURE

553

THURSDAY, APRIL ii, 1895.

PHYSIOLOGY OF THE EXCITABLI:
TISSUES.
Elcctrophysiologie. Von VV. Biedermann, Professor der
Physiologic in Jena. (Jena: Fischer, 1895.)

PROF. BIEDERMANN, who was not many years
ago promoted to the chair of Physiology at Jena, is
well known as having co-operated with Prof. Hering in a
very extended series of researches on the "general
physiology of muscle and nerve," of which the results
have been communicated to the Vienna Academy from
time to time during the last twenty years. The present
work will be welcomed by physiologists in the hope that
it will not only place at their disposal the rich harvest of
the author's persevering labours in this field of inquiry,
but that it will afford to him the opportunity of dealing
more completely than has hitherto been possible with
one of the most fundamental characteristics of the animal
organism — its power of responding in a specific way to
stimulation. This being, as we learn from the introduc-
tion, the purpose of the book, the title " Electrophysio-
logic " may seem scarcely suitable, for however intimate
and essential may be the relation between vital processes
and the electrical phenomena which accompany them,
these, after all, are only concomitants, and must be
thought of apart from the process itself. However this
may be, the author makes it quite clear that his scope is
not electrical, but purely physiological. Referring to the
" Muskel-physik" and the " Nerven-physiologie" of
Prof. Hermann, published in 1880, he declares it to be
his purpose to bring the subjects therein treated up to
date, and in doing so to follow the true physiological
method.

" In morphology it is obvious that we must proceed
from the simple to the more complicated, but in physio-
logy . . . the opposite is in a certain sense the case.
Under the apparent simplicity of an amoeba manifold
physiological functions are latent.'' " The most various
duties are performed by the same protoplasm, whereas
in the higher animals each particular cell is devoted to
a specific function, and consequently affords a better sub-
ject of study than the protozoon, when the nature of that
function is to be determined." It is for this reason that
" our knowledge of contraction and of the processes
which are associated with it have been advanced in-
finitely more by muscle physiology than it ever could
have been by the microscopical e.xamination of the lower
organisms." (p. i.)

The volume before us is the first part of a work which
is to include the whole of the physiology of the '" excitable
tissues." Its 440 pages relate directly to muscle, but
also comprise the electromotive properties of epithelial
and gland cells. In accordance with the general principle
that the study of structure must precede that of function,
the book opens with a very useful chapter of anatomical
prolegomena, in which, beginning with a section on the
contractile fibres of the stem of vorticella, the author
proceeds to the epithelial nerve-muscle cells of the
coelenterates, and so on to those of the worms. Then
conic in order the muscular elementsof .MoUusca (Lamelli-
N(l. 1328, VOL. 51]

branchs and Gasteropods), of interest as showing the
striking relation of structure to physiological endowment.
Next we have before us the simplest forms of muscle-
cells in vertebrates, and finally the structure of striped
muscle, with reference to which we again find that
the relations between anatomical characteristics and
functions receive more attention than the endless
questions of histological detail which, in the minds of
most students, are associated with this subject.

Of the 340 pages given to the physiology of muscle,
scarcely a third relate to its electrical properties. These
comprise four sections. The first and second deal with
the electromotive phenomena of muscle at rest and in
action ; the third relates to the so-called " positive
variation ' ; the fourth to secondary electromotive
actions. Throughout it is felt that Biedermann writes
as a physiologist, not as a physicist, availing himself of
the best physical methods to investigate phenomena,
but regarding them not as the thing itself, but merely as
indications, by the aid of which the time and place rela-
tions of vital processes become known to us. In this
tendency to take things as they are, postponing
theoretical speculations, until the results of the more
exact methods of observation which we are now only
beginning to know how to use, have been systematised,
Biedermann is happily at one with all the leaders of
thought and work in this field of inquiry.

Among the most interesting of the observations by
which Prof. Biedermann has contributed to the advance
of what may, in the truest sense, be called elementary
physiology, are those by which, in co-operation with his
master, and, it may be added, in language not unfamiliar
to English students, he has sought to work out that
notion of ana anA ca/a, or of A and D, as Hering puts
it, in accordance with which the influences exercised by
one part of the organism on another through the nervous
system, are regarded as manifestations of two antagon-
istic tendencies, the one quelling, the other e.xciting in its
nature. This principle, which Prof Hering first invoked
to explain certain antagonisms relating to the perception
of colour, has served Biedermann as a guide in the
study-'of similar antagonisms in the behaviour of muscles,
and he has furnished us with several instances showing
that in the responses of muscles to the stimulation of
their nerves, we may have to do not with spur only, but
with a mixture of spur and bridle, a co-operation of
quelling and exciting influences conveyed to the re-
sponding muscle by the same channel — its motor nerve.
In Biedermann's very interesting third section, the
reader will find this subject fully discussed. The gist of
what he has observed is as follows : — The change of
form by which a muscle responds to stimulation of its
nerve is not always, as is ordinarily the case, of the
nature of shortening or contraction. Under certain well-
ascertained conditions the " normal " eflfect is reversed :
the muscle relaxes. By comparison of the instances
in which this happens, we learn that the anomaly (it
we are to call it so) depends on the terminal organ,
not on the nature of the stimulus, or on the channel by
which it is conducted. For it is found that muscles
which normally exhibit no tendency to respond by re-
laxation, acquire that tendency when they have under-
gone " modification,' either by the persistent action of

B B

554

NA TURE

[April i r, 18915

certain external causes or under exceptional physiological
conditions ; and, moreover, that in certain invertebrates
the constant condition of the muscles corresponds rather
to the modified than to the ordinary state of the muscles
of the higher animals. If we proceeded to inquire in
what this modification consists, Biedermann's answer
would be that it may be distinguished in all cases by its
electrical concomitants— all "modified" parts being
relatively negative to similar parts which are unmodified.
Thus when the adductor muscle of the nipper of the
crayfish, which is normally in a state which resembles the
" modified'' state of an ordinary muscle, passes into a con-
dition corresponding to that which is normally present
in the muscles of the frog, a change takes place in the
electrical relations of the structure of such a character
that the sign of the electrical response to stimula-
tion is reversed ; it becomes negative instead of posi-
tive. Comparing these facts with others relating to
vision, with the processes of secretion, and with other
processes under the immediate control of the ner-
vous system, one is encouraged in the hope that
the relations between ana and cata, between rest and
activity, between restoration and exhaustion, between
integrity and hurt, will eventually be linked together
by their electrical concomitants, and that by these
characters it may be possible to ascertain with exactitude
and certainty in how far these various antagonisms may
be referred to a common principle.

.Space will not allow us to give an account of the last
chapter in Prof. Biedermann's book, which contains
much that is new and important relating to the electro-
motive phenomena of secreting cells. Enough has been
said to satisfy the physiological reader that the book is
one which will have permanent value. It is, moreover,
readable. The author tells us in his preface that he has
done his best to get rid of " lehrbuchmiissige Trocken-
heit." We think that he has fairly succeeded.

J. BuRDON Sanderson.

THE PHYSIOLOGY OF PLANTS.

A Popular Treatise on the Physiology oj Plants, for the
use of Gardeners, or for Students of Horticulture and
of Agriculture. By Dr. Paul Sorauer, Director of the
Experimental Station at the Royal Pomological Insti-
tute in Proskau (Silesia). Translated by F. E. Weiss,
H.Sc, F.L.S., Professor of Botany at the Owens Col-
lege, Manchester. (London : Longmans, 1895.)

OF all the sections into which the teacher of botany
must divide his subject, perhaps the most difficult
for him to deal with is that of vegetable physiology. No
adequate elementary text-book has hitherto existed in
English, the classical works of Sachs and Vines being,
by their very completeness, too bulky and too fall of
detail for the student who is beginning the study of the
subject. The work of Dr. Sorauer is intended to supply
this deficiency. It is written especially for those whose
interest in the matter is a practical one, and it deals,
consequently, miinly with those ciuestions which arc of
interest to the horticulturist as bearing on the problems
of cultivation. Approaching the matter, however, from
this side only, the book, as a work on physiology,
NO. 1328, VOL. 51]

to a certain extent comes short of what is needed,
as many important sections of the subject are left
untouched.

The author deals almost entirely with the problems of
nutrition and their bearings on the details of horti-
cultural practice. -Vt the outset he strikes a rather
heavy blow at what has hitherto been, unfortunately,
the pron'.inent idea of most agriculturists and horti-
culturists as to what constitutes the scientific side
of agriculture. The latter has been held to embrace
little or nothing beyond the chemistry of the soil,
and everything not directly connected with this has
been pushed into a secondary position, the metabolism
of the plant ani the chemical changes of its constituents
being generally very superficially treated and held of
not very great interest. It certainly seems strange that
those who have been engaged especially in the cultivation
of sensitive organisms under very varied and rapidly
changing conditions should have given so little atten-
tion to the physiological peculiarities which these organ-
isms present, and to their power of availing themselves
of the various advantages that their environment offers
to them. Dr. Sorauer, at the outset, strikes the right
line when he points out that the chemistry of the soil, im-
portant as it is, plays only a secondary part in the de-
velopment of the various plants which that soil supports,
and directs his readers' thoughts chiefly to the problems
of nutrition which the plant itself olTers for consideration,
showing that it is the business of the cultivator to
endeavour to guide the natural development of the
plant towards the special ends which are the needs of
horticulture.

This idea, put prominently forward in the opening
chapters, runs throughout the whole of the book. In
developing it, the interactions between the soil and the
plant, or between the plant and the atmosphere, are kept
in the foreground, so that the gardener may realise tli.u
he is face to face with an actual struggle that is going on
continuously between the organism and its environment,
and that he is working to secure that in this contest those
conditions of the latter maybe secured which are most
favourable to the success of the organism, and hence 1 1
its most complete development.

In the earlier chapters of the book, the author treats
successively of the several members of the plant, the
root, stem, leaf, tlower, and fruit. Without going very
deeply into their anatomical structure, he explains it
sufficiently for the student to get an adequate compre-
hension of the duties or functions which are especially
discharged by each. Again his mode of procedure is
sound, as it is only function that gives the clue to the
right interpretation of structure. The method, as
carried out by Dr. Sorauer, is, however, open to a little
objection, as it has led him rather to push too far the idea
of the several members of the plant living for themselves,
and to relegate a little to the background that of the
plant being an organic whole, differentiated in dilTerent
directions for the carrying out of dilTcrent functions.
Thus the leaf is spoken of as passing oil' into the vascular
bundles of the axis only such materials as it cannot at
once employ for its own growth, leading the student
probably to the conception that the latter problem is for
the leaf the primary one, and that the nutrition of the

April i i , 1^95]

NA TURE

555

whole organism is only subsidiary when the relation of
leaves to the rest of the plant is considered.

The chapters on the general processes of horticulture ;
the correlation of stems and roots, and their separate
treatment ; the principles of manuring ; the theories of
the proper supply of water to the plant, the aeration of
its roots, &c., will be read with much attention, and will
be found very useful in actual practice. The deposition
of nutritive material in various parts of the plant, and
the ways in which this can be influenced by different
modes of treatment of the shoot at different ages, deserve
careful study. The relation of such questions to the
operations of pruning, grafting, &c., is discussed at some
length, and the development of vegetative or fruiting
branches respectively, is shown to be capable of great
modification in the hands of the skilled horticulturist.

The book, however, though a valuable one for prac-
tical gardeners, leaves something to be desired as a
contribution to the literature of vegetable physiology.
Indeed some of the fundamental facts of the metabolism
of the cell are, if not inaccurately, at any rate not clearly
stated. The absorption of water is certainly one of the
most important processes which it carries out. As de-
scribed on p. 127, the early changes in the young cell
connected with this process are stated as follows : —

" Very soon there arise within the protoplasmic mass
which fills up the cells, very small quantities of liquid
substance (cell sap) which collect together to form small
vesicles (vacuoles), and these give to the protoplasm a
foam-like structure. Now, as the protoplasm becomes
used up during the elongation of the cells, the vacuoles
increase in number, run together, and force the remainder
of the protoplasm outwards towards the cell wall."

Put in this way, the student would get the idea that the
elongation of the cells takes place apart from the entry
of water, and that the formation of the vacuole, that is,
the increase of the cell-sap, is rather the result than the
cause of the extension of the cell. No statement is made
as to the cause of the entry of the water, the osmotic
activity of the cell-contents, which really underlies all
cell-growth.

Another strange statement is that the main cause of
the growth in length of a young stem is the longitudinal
tension in- the pith, which "drags the young ring of wood
with it, as long as the latter is still soft and thin-walled."
This will be a new view to most physiologists.

Dealing with the absorption of nitrogen by certain
leguminous plants, and the recently established fact that
the atmosphere is a source of supply of this constituent^
the author commits himself to the view that this
absorption is carried out by means of their leaves.

In section 23, which treats of the substances formed by
the leaves, we find several statements to which exception
must be taken. The classification of the vegetable
proteids is inaccurate, the latter being said to consist of
albumins, caseins, and fibrins. Albumins are extremely
rare in plants, and fibrin resembling animal fibrin is un-
known. Globulins, which are numerous and varied, and
albumoses, which have comparatively recently been in-
vestigated, are not even mentioned. The formation of
starch grains in the leaves is thus described —

" When the light shines on the leaf its transpiration is
exactly increased, and its cells lose some of their water ;

NO. 1328, VOL. 51]

then we may imagine the starchy substance to be forced
out of the thickened (concentrated) cell-sap, and the
latter will become more liquid.'

The nutrition of the cell is summed up in the remark-
able sentence :

" The nutrition consists in this, that the raw mateiials
which enter the cell are attracted, now by one, now by
another of the constituents of the cell, and adopt its
specific movements, and are thus transformed with the
same substance (assimilated)."

These drawbacks to an otherwise valuable work make
one regret that Prof. Weiss has confined himself to trans-
lating Dr. Sorauer's text. Had he rather edited than
translated it, no doubt we should have found the English
edition free from these defects.

MINES AND MINERALS.
Traiie ties Cites Mincraux et Metallifcrcs. Cotirs de
G^ologie appUqu^e de VEcole SupMeure des Mines.
By E. Fuchs and L. de Launay. (Paris: Baudry,

,18930
Etude industrielle des Gites M^tallifires. By George
Moreau. (Paris: Baudry, 1894.)

IN these days, when memoirs and papers follow in
rapid succession, the geologist and the miner are
justly grateful to any careful compiler who will aid them
to keep pace with the ever-widening flood of technical
literature. The debt of gratitude is increased when the
task is undertaken by a writer like Prof, de Launay, who
brings together into one colossal work the results of the
labours of his master, the late Prof. Fuchs, and of his
own personal researches.

The book is a treatise upon applied geology, which
Fuchs defined as the application of geological knowledge
to seeking and working mineral deposits. Very rightly
Fuchs took a wider basis for his course of lectures at the
Paris School of Mines than mere ore deposits. He
recognised the fact that the mining engineer of to-day
must be a man of wide attainments, capable of giving an
opinion upon all sorts of mineral workings, reporting
upon gold mines in one journey, upon gem-diggings in
the next, and a little later being asked to determine the
value of deposits of phosphate of lime or other earthy
minerals. For work of this description Prof. Fuchs'
lectures formed an admirable kind of training, which has
too often been neglected in the past ; in fact, until this
treatise appeared, many geologists may have failed to
realise the vast importance of the subject.

While admitting that various systems of classification
may be adopted. Prof, de Launay says that he felt bound
to arrange his minerals according to the metalloid or the
metal, and he chooses the so-called chemical order. In
a huge book of this description, alphabetical order would
have been more convenient, and would have prevented
some of the anomalies which cannot help striking the
reader. The chloride, carbonate, and sulphate of sodium
appear under the head of that metal, whilst the borate
and nitrate are classed respectively under boron and
nitrogen ; again, chalk and gypsum are brought under
calcium, whilst apatite is placed under phosphorus, no
doubt for the reason that the non-metallic element is the

556

NA TURE

[April i i, 1S95

one to which the mineral more especially owes its com-
mercial importance. While slate is sandwiched in
between the gems, under the heading "Silica and
Silicates," clay is relegated to " Aluminium."

In a general treatise upon mineral deposits, exception
may fairly be taken to the absence of any mention of
coal ; the author excuses himself on the ground that fuel
forms a special subject too vast to be included within the
compass of his book. The overwhelming importance of
coal seems, on the other hand, an additional reason for
finding it a place in a work which is practically an
encyclopasdia of applied geology ; besides, if fuel is to be
omitted, why are natural gas and petroleum inserted .'

In a gigantic work of this description, it is impossible
for an author to avoid some errors. Five mistakes in
spelling Welsh words in the first three lines of p. Ixxviii.
will not be looked upon as a heinous crime by the
average Englishman, who himself feels that he is skating
upon thin ice when he is dealing with the orthography
of names of places in the Principality ; however, these
are not the only cases of misprints which might be
noticed.

The geo;jraphical tables, occupying forty-five pages,
form a useful feature in the book ; an alphabetical list is
given of the principal minerals worked in each country,
together with references to the pages where they are
described. These tables and the index of localities take
the place of a general index, which is not supplied.
Small maps inserted in the text are of much assistance
in enabling the reader to follow the author's descriptions ;
the total number of woodcuts, 390, may seem large, but,
scattered as they are through more than 1800 pages,
they are not as numerous as one would like. Great
pains have been taken with the bibliography, and Prof,
de Launay's lists will often bring into notice original
papers which would otherwise have passed unnoticed.

Though too expensive for the pockets of ordmary
students, the book will find a place in the libraries of all
mining schools and geological and engineering societies,
and it is sure to be frequently consulted with profit by
geologists and mining engineers.

Moreau's work has a totally different object to that of
de Launay ; the latter is a record of observc^l facts,
whilst the former, dealing solely with metallic ores, is
mainly devoted to general principles. After describing
briefly the classifications of ore deposits proposed
by von Groddeck, de Lapparent, Phillips, Whitney
and Raymond, the author suggests one of his own,
viz. : —

(A) Stratified deposits.

(B) Eruptive deposits.

(C) Deposits m pre-existing cavities.

(D) Substitution deposits.

Mineral veins are classed under the head (C), and
apparently Moreau does not admit that they may some-
times be substitution deposits.

Two ch ipters are devoted to disquisitions upon the
origin of mmeral ve ns, an I are based upon the works of
Uaubrde, Lyell, Elle de lieaumont, De la Uechc,
Hcnwoid, Moissenet, Ccikie, and others; Vogt's recent
researches and theories remain unnoticed.
N 1. 132S. VOL. 5 I 1

Chapter v., which treats of the chemical and physical
characteristics of ores, and the earthy minerals which
accompany them, should have been omitted ; and the
same remark applies to the chapters upon qualitative
testing, quantitative assaying, dressing and smelting.
These subjects cannot be taught in a few pages, and are
better studied in the ordinary text-books.

Chapter vi., largely borrowed from von Groddeck,
Phillips, Kuchs and de Launay, contains descriptions of
well-known characteristic ore deposits. The important
iron ores of the Secondary rocks are dismissed in a very
cavalier fashion, for, strange to say, no mention is made
of the great iron-field of the Department of Meurthe and
Moselle, Lorraine and Luxemburg.

The most valuable part of the book for mining men will
be found in two of the concluding chapters, which deal
with the study of ore depo>its from a purely commercial
point of view. They are full of useful hints and warnings,
not only to the engineer who is examining mining pro-
perties offered for sale, but also to the capitalist who
is meditating their purchase. M. Moreau is evidently im-
bued with many of the ideas which were running through
the brain of Mr. J. H. Collins when he delivered his
recent presidential address to the Institute of Mining and
Metallurgy. The more deeply counsel of this kind is
taken 10 heart, the better will it be for investors in mining
enterprises.

A few errors in the names of well-known geologists
are inexcusable. It is strange that any one should write
" Sir RichurJ Lyell '' ; " Sir Logan Foster, Whitney," is
evidently meant for "Sir William Logan, Foster and
Whitney " ; even Elie de Beaumont's name is not always
spelled correctly. " Gossan " is a Cornish and not a
Welsh term, as supposed by the author.

OUR BOOK SHELF.

Elementary Text-book of Afetallurgy. By A. Humboldt
Sexton, F.I. C, &c. (London: Griffin and Co., 1895.)

This book is intended, for those who are commencing
the study <if metallurgy, as a kind of preparalory course
to that of Prof. Koberis-Austen. as given in his '■ Intro-
duction to the Study of Metallurgy," which the student
is advised to read after digesting the contents of Prof.
Sexton's manual. The work is got up in good stjie by
tlie publishers, and printed in a clear and distinct manner.
Willi the general arrangement there is very little to
complain of ; but the same by no means can be said of
the subject-matter, which contains many errors, and the
definitions are often expressed in such crude language
•hat a student might be easily misled in taking his first
lessons in metallurgy from its pa>;es. 1 he following
examples may be cited :— P. 3: M.ilk-abiliiy. This Is
the property of being expanded into sheets. Duciility:
Tills IS the property of being drawn into wire. A small
quantity of antimony in lead is said to make it quite
brittle. P. 4 : Lead may be drawn into wiie if means
betaken to prevent the metal being subjeil to stress.
P. S ; With reg.ird to tensile testing, the author says
that elongation takes place mostly near the point of
fracture. P. 46 : There are but two neutral substances
in general use, ginphile and chrome iron ore. P. 89 :
Fluor spar is said to be used 10 increase the qu.antily of
slag. On pp. 92 and 121 : C below 5 is lerined wroutjht
iron, and steel when C is between 5 and 15 ; while on

April i i, 1895J

NA TURE

557

p. 1 10, it is stated that, in puddling, the carbon is reduced
to 'I per cent. ; and also that during; the melting-down
stage there is little chemical action. P. iii: Puddled
bloom is chemically wrought iron wiih intermingled slag.
P. 123: Steel is made by carbonisini^ malleable iron.
P. 12S : Mild steel, not more than 5 per cent, carbon,
does not harden when heated and quenched in water.
P. 134 : The slags from the acid Bessemer process are
very iiasic silua/es oi iron and manganese. P. 13S: In
Open Hearth process it is stated that the iron ore should
be as free as possible from silica, whereas the Spanish
hematite usually employed is very siliceous. P. 143:
The strength increases as the diameter of the wire
decreases. Also cake or tough copper may contain any
amount of impurities. P. 223 : An alloy of 80 per cent,
copper and 20 per cent, zinc is called red brass. P. 229 :
Electro refining of copper ; the anode is a thin sheet of
copper ; the cathode is a bar of blister copper . P. 230 :
The passage of the electric arc through the carbons pro-
duces a very high temperature. It is a great pity that
a work which has been so judiciously compiled as the
present one should be marred by so many mistakes,
when by a more careful supervision of the proof sheets
they might have been easily detected and corrected.

Annals of liritish Geology, 1S93. A Digest of the Books
and Papers published durmg the Year. Ey J. K.
Blake, M.A., F.G.S. (London : Dulau and Co., 1895.)

Once more has Prof. Blake overcome all the obstacles
of prolonged research among publications that are many
of them difficult of access. Once more has he braved the
disappointment of inadequate suppoit, and following his
own independent course in the selection and arrange-
ment of his material, he has now given us the fourth
volume of his "Annals of British Geology." Every
addition to the series renders the whole of greater value,
and we sincerely hope that the present volume will be
self supporting, as he ventures to anticipate. To all
geologists, and to the provincial worker especially, these
"Annals" must be of the greatest service, for the author
contrives to give so much of the substance of each paper,
that the leader will gain a very fair notion of the
additions made to our knowledge during each year.
Except in the student's special department of work, there
will be no occasion to consult the originals.

Altogether 730 papers and books are noticed, being an ;
increase of 180 over those recorded in the previous
volume. The author's introductory review, occupying
twenty-four pages, gives a summary of the chief geo-
logical news of the year. Although not essential to the
Annals, this review acts as a safety-valve for the escape
of some few of the critical remarks which arose while the
author was perusing the 730 works. New forms of
Ammonites and Corals come m for critical observations,
so also do the "hemera;" of the Inferior Oolite, and
various glacial theories. |

In Palaeontology the place of honour is rightly given to '
the Elgin Reptiles described by Mr. E. T. Newton, and
an excellent illustration of ElgiiUa mirabilis forms the ,
frontispiece of the book.

The Origins 0/ Invention. By Otis T. Mason, A.M.

Ph U Pp. 419. (London ; Walter Scott, Limited,

1895.)
Tu trace our modern industries to their origins, to show
how they have evolved, and to point out the changes
from naturalism to artificialism that mark the course of
civilisation, is a difficult task, but an attractive one ; and
few ethnologists are better equipped with facts relating
to this development than the Curator of the Department
of Ethnology in the L'nited States National Museum,
who is the author of this book.

NO. 1328, VOL. 51]

Dr. Mason lays down the following as the order in>
which kinetic energy has been con)manded : (1) man-
power in every pursuit ; (2) fire as an agent in cooking,
pottery, metallurgy, &c. ; (3) the power of a spring, as
in a bow or trap ; (4) beast-power, for burden a.id trac-
tion ; (5) wind-power, on sails and mills, and in draught;
(6) water-power, as a conveyance and a motor, and
gravity or weight generally ; (7) sieam-power, utilisation
of an expanding gas ; (8) chemical power, in the arts of
the civilised ; (9) electric power, motors, message-
bearers, in mechanics and illumination ; (10) light as a
mechanical servant, only beginning 10 be domesticated.

Prominent among inventions are tools and mechanical
devices — objects employed as means to ends. .Many of
these have come down from remote antiquity. Follow-
ing M. Adrien de Mortillet's classification. Dr. viason
describes the tools and appliances used by primitive
peoples for cutting ; abrasion and smoothing ; fracturing,
crushing, pounding; perforating, grasping, and jointing.
At the basis of tool-using, lie the systems of counting
and weighing and measuring, all of which receive
attention.

The invention and uses of fire, forms the subject of a
very interesting chapter. < ther matters treated in
separate sections are stone-working, pottery, primitive
uses of plants, the textile industry, inventions belonging
to the chase, methods used for the capture and domestic-
ation of animals, means of travel and transportation, and
instruments of warfare.

The work is readable throughout ; it is a valuable
history of the development of the inventive faculty, and
has, therefore, an important relation to the history of
humanity. The ethnologist will find in the volume much
that is interesting in regard to the relationship between
man's activities in different regions.

Short Studies in Nature Knowledge. By William Gee.
Pp. 313. (London : Macmillan and Co., 1895.)

For boys in the upper standards of our elementary
schools, this forms an idea! reading-book. It is simply
worded, is not too full of details, contains numerous illus-
trations, and is likely to create and fo-ter a love of
natural knowledge. The book is intended to be used as
an introduction to physiography, and it covers the ground
usually understood to belong to that science. Copious
extracts from the poetical and prose writings of standard
authors are introduced into the text wherever possible,
and serve to lighten it. The author appears to have
spent a deal of care upon the work, and wc think he has
succeeded in producing a volume which will be welcome
to teachers, as well as readable to all who find pleasure
in the study of inanimate nature.

Organic Chemistry: The Fatly Compounds. By R.

Lloyd Whiteley, F.I.C., F.C.S. Pp. 291. (London :

Longmans, Green, and Co., 1895).
This is another elementary science manual "written
specially to meet the requiicments of the elementary
stage of science subjects as laid down in the s)llabus of
the Directory of the Science and Art Department." It
is hardly a book that we could recommend to followers
of departmental organic chemistry, and certainly not
one to be adopted by other students of the science. It
is most unequal in structure, and very deficient in parts :
Chapter iv., on percentage coinposilion and empirical
formulas, consists of less than one and a half pages. As
well-known standard works have been " freely employed "
in the preparation of the volume, it is difficult to re-
cognise the sections for which the author is responsible,
and therefore undesirable to impeach the accuracy of
some of the information.

■)0<

NA TURJi

[Al'KIL I I. 189:

LETTERS TO THE EDITOR.
The Age of the Earth.

I AM surprised to observe, in the article which Prof. Sollas
has written on this subject in your issue of the 4th inst., p. 53 j,
that he speaks with approval of Dr. A. R. Wallace's method of
calculatine the earth's age. About two years ago (I hive only
this week's number of Natl'RE at hand) I wrote to you on this
subject, and was undenthe impres>ion that I hid proved the
complete fallacy of Dr. Wallace's method of calculation.

To put Dr. Wallace's view briefly, he assumes that deposition
within a limited areaof, if I remember rightly, 3,000,000 square
miles, goes on 19 times as fast as denudation over the whole
land area, which is 19 times as sreat, and then argues that the
whole maximum thickness of the stratified rocks (and hence the
earth's age) could be deposited m 1/19 of the time required to
carry away from an equal area of land an equal bulk of material.

The falKicy consists in assuming that a great rapidity of deposit
over a limiied area can in some way allow of the deposit or
formation of sedimentary rocks at a greater rate th.in that of
denudation.

It is obvious that, in a given lime, no greater volume of deposits
can be formed than the volume of material denuded in the same
time. If, therefore, as Prof. Sollas assumes, 1/2400 of a foot of
sediment per annum is denuded from the land ari-a, by no ar-
rangement can a land area of equal extent, consisting of sedi-
mentiry rocks of the same composition and thickness as those
which actually constitute the land area, have been formed as a
whole more rapidly than I fool thickness over 5 7,000,000 square
miles area in 2400 years. Taking the estimate of Prof. Sollas,
viz. 164,000 feet, as the maximum thickness of the sedimentary
rocks, and taking the existing land area to be accounted for as
57,000,000 square miles, the lime required to form an area of
57,oco,ooo square miles of rock 164,000 feet thick, at 12400
of a foot per annum, is 393,600,000 years, unless the area under-
going denudation was greater or less than it is at present (and
it could not be four times as great as at present). No con-
centration of the deposit over a small area would shorten the
lime required by a single moment. Bernard Hobson.

If, in the compass of a short article, I did not allude to the
controversy which followed the attack made by Dr. Hobson
(Nature, vol. xlvii. p. 175, 226) on Dr. Wallace's method of
estimating the age of the stratified "seiies, it was because I
thought, as I do still, that the honours of that controversy rested
entirely on the side of Dr. Wallace.

There is no fallacy in Dr. Wallace's argument, but a strange
misconception on the part of Dr. Hobson, which arises from his
consistent disregard of the word maximum as prefixed to the
estimated total thickness of stratified rocks. It is obvious that
stratified systems cannot have a /«ajr««/«;« thickness everywhere
over the whole 57 million square miles of the land suiface. As
a matter of observation, a system attains its maximum thickness
over a very limited area, and over a large part of the 57 millions
of square miles of land surface it has no thickness at all, or, in
other words, is entirely absent. If " maximum " could be made
to mean the same as "average," no doubt Dr. Hobson's con-
tention would h lid, but those who have made use of a
maximum in estimating the age of the stratified scries have
observed a strict distinction in the application of the two terms.

Rathgar, Apnl 9. W. J. Soi.las.

Poly em bryony.
I.N connection with the note in the last number of Nature
on the above, I think it should be known that llie phenomenon
was incidentally observed some two years ago in the re<l beet
(Hela rubra) by the late Mr. Romanes and myself. We found
that a single seed might produce as many as four distinct plants,
and as (ar as our observations went, polyemhryony was quite
the normal condition. It seems lobe more characteristic ol the
Gymno-perms than the Angiospcrini, and has ol course been
investigated in the former, and in the latter among the Mono-
cotyledons (Treljakow) and Dicotyledons (t.g. Citrui-St.ra.-i-
burger). The (act of its occurring in such n common type as
£. rubra should, I think, lie taken advantage of by some
botanist, as the results could not fail to be both interesting and
important. Tretjakow's discovery that the supernumerary
embryos in Monocotyledons may be produced by the antipodal
cells, certainly suggests his compaiison between such embryos
and those pro luced by [parlhenogenelic?] apogamy on the
prothallia of the lower plants. Kra.sk I. Cole.

NO. 1.^78. VOL. 51]

IMPROVEMENTS I.V PHOTOMETRY.

XT EARLY sixty years have passed since it first oc- 1
-'-^ cuired to the philosophic mind of Sir John 1
Herschel to attempt an arrangement of the relative
brilliancy of the stars, upon a method that should be
more secure than the eye estimations that had done duty
for many centuries. It is not necessary to enter into any
description of his method, which may be regarded now
as entirely superseded. Doubtless, had he been sur-
rounded by skilled workmen, furnished with better tools,
the cumbrous method employed would have been sim-
plified, but the establishment of an observatory remote
from the assistance and contrivances of the workshop is
not without drawbacks, as he and others since h.ive dis-
covered and regretted. About the same time, Seidel,
in Germany, was at work on the same problem, and the
fact that two astronomers, independently of each other,
undertook the solution of the same problem, is a proof
that it was ripe for mature consideration, while the series
of astronomers who have laboured in the same path
confirms the suspicion that this kind of investigation too
long neglected offered a field having a rich prospect of
reward.

But a photometer at once convenient and capable of
general application to the stars remained to be invented,
and this want was effectually supplied by ZoUner, who
proposed a form of construction which has certainly ob-
tained the most general use of any of the suggestions
that have been from time to time put forward by astrono-
mers, who have recognised its deficiencies and tried to
remedy thetn. The distinguishing characteristics of the
Z<)liner photometer are the introduction of an artificial
star formed from a lamp shining through a small aper-
ture, and the controlling of the light of that star by means ]
of polarisation. This principle is now of such general use I
that no lengthened description is necessary. But to ex-
plain the reason for the introduction of other forms of
photometer, it is necessary to point out what are, or
what were, considered to be its defects by those who tirst
used the instrument, defects which it is believed care and
experience have sinccdone much todiminish.if not entirely
to remove. A source of error might be anticipated in the
varying brilliancy of the lamp employed to form the
artificial star, and in the early days of the instrument
this was a fruitful source of annoyance. Next, the light
of the lamp had to strike no less than twenty-eight sur-
faces, and apart from the difficulty of getting so many
surfaces true, and ensuring the parallelism of the Nicol
prisms by which the diminution of the artificial star !■;
effected, there is also to be considered the inevitable loss
of light at so many surfaces. One consequence of this is
that the brightest stars of the heavens are a])t to be
brighter than the artificial star, and since the observa-
tion is inade by reducing this light to match that of the
real star, it is necessary to have recourse to some such
expedient as reducing the aperture of the telescope.
And then a difficulty is encountered which has not yet
met with a complete explanation. The light deducted
from the star, as seen with a reduced aperture, does not
coincide with that which would be predicted from theory.
In some of the recent series of observations the dif-
ferences between observation and theory are as great as
they are perplexing. " There can be no doubt," wrote
Mr. C. S. I'eirce, of Harvard, twenty years ago, " that the
errors introduced by the use of these diaphragms are
by far the most serious of those by which my observa-
tions are effected." Dr. Wolff met with similar difficulties,
and dotibtless anomalies such as these have encouraged
the production of other photometers which should be
free from the suspicion of error. Having regard to the
photometric work actually accomplished, we may confine
attention to two forms of apparatus known as the Picker-
ing Meridian Photometer and the Pritchard Wedge

Ai'KiL 1 1, 1^95

NA rURE

559

Photometer. In the first of these the principle of polar-
isation is still used, but the artificial star is discarded.
This is apparently an advantage, but it is a question if
it does not introduce an error as large as that which it
seeks to eliminate. An image of a star, as Polaris, is
used as the constant of comparison, and this image can
be reduced by polarisation till it equals that of the star of
which the magnitude is sought. A lack of resemblance
between the stars under consideration is removed, but
the removal is effected by the introduction of a second
object-glass with evidently different optical capacity,
requiring a fresh constant to be determined. Prof.
Pickering's photometer consists practically of two tele-
scopes, placed at right angles to the meridian, and over
each of the object-glasses is placed a right-angled prism.
By means of the northern prism the image of Polaris
is reflected, and by suitable adjustment can be made to
occupy any convenient position in the field of view,
while the prism on the other object-glass can be set to
any declination so as to bring the image of any other
star, when on or near the meridian, into ju.xtaposition
with that of Polaris. Ingenious arrangements are intro-
duced to ensure the coincidence of the pencils forming
the images to be compared, and a control over the
accuracy and efficiency of the whole is secured by con-
trasting the brilliancy of Polaris with itself — that is, by
comparing the images formed by either object-glass.
This is effected in all cases by rotating a Xicol prism in
the eye-piece of the telescope through a measurable
angle, and thus equalising the lights of the stars by
means of varying the planes of polarisation. How
effective this instrument has proved itself in the hands
of Prof. Pickering, we shall presently see.

But either of these forms of photometer is necessarily
a special production, and therefore the object-glasses are
small and the light-gathering powers limited. In Prof.
Pickering's first photometer, the aperture was only 4 cm.,
with a magnifying power of only fifteen diameters. Prof.
Pritchard, considering this limitation a defect, directed
his attention to the construction of a photometer which
should be readily available on any instrument, and be
applicable to stars of very varying degrees of brightness.
For this purpose he had recourse to the principle of e.<-
tinction of the light of a star, by means of a wedge of
neutral-tinted glass, which could be moved over the image
of a star till its rays were lost by the gradual increasing
thickness of the medium through which they had to
penetrate. This principle had been used by the late
Mr. Dawes, and also by Capt. Abney, but the long-con-
tinued use of such an apparatus by the late Savilian
Professor is likely to connect his name with this form of
photometer. The main defects in its construction arise
from the difficulty of obtaining an absorbing medium
equally operative throughout the entire length of the
spectrum, and also that of determining with certainty
the coefficient of absorption — in other words, how
much light is lost by the difference of thickness cor-
responding to one inch in length of the wedge. Recent
and more exact methods than those employed by Prof.
Pritchard seem to show that the constant used in his
work is in error, and that a correction to his magnitudes
so obtained is necessary. But it is a peculiarity of the
form of construction and method of observation adopted
that such a correction can be very easily applied.

These forms of photometers, the/Collnor, the Pickering,
and the Wedge, are the three instruments which have
been most generally in use, and with which the modern
work has been accomplished. The rapidity and the
progress of this class of observation can easily be shown
by a few statistics. Previous to their introduction, exact
photometry was limited practically to two catalogues.
Exact photometry is, of course, a relative term ; it is
meant to include observations other than eye estimations,
and therefore Herschel and Seidel, the one with 69 stars,

NO. 1328, VOL. 51]

the other with 208, are the only two observers to whom
it is necessary to refer. Since the introduction of the
more rapid methods, and possibly from a better appre-
ciation of the importance of the inquiry, we have had
many extensive catalogues. Leaving out Zollner him-
self, who did not attempt to condense his observations
into catalogue form, we have —

Peirce's Harvard CataIo5;ue of 494 stars.
Wolff's First Honn Catalogue of 475 ,,
Wolfl's Second Catalogue of 923 ,,

Potsdam Photometric Catalogue of 3522 ,,

All these catalogues have been made by means of a
Zollner photometer, but the list in no way e.shausts the
photometric work that has been done by this instrument.
For instance, Lindemann, at Pulkova, has carried out a
long series of observations with the view of determining
the scale that has been unintentionally adopted in the
record of eye estimations in various catalogues. Ceraski
and others have been at work on variable stars, while
interesting inquiries into the extinction of light by the
atmosphere and other physical investigations have been
made by its aid. A debt of gratitude, therefore, of no
common kind is due to the ingenuity of Dr. Zollner. Con-
fining our attention, however, solely to the compilation
of catalogues, we have with the Pickering meridian pho-
tometer a collection of the relative magnitudes of 4260
stars, followed by a photometric revision of the Durch-
musterung of Argelander, in which are given the magni-
tudes of some 17,000 stars. This leaves out of the
summary a quantity of miscellaneous work on the
Pleiades, on the .•\steroids, on double stars, standard
stars, &c. In fact. Prof. Pickering has placed it on
record, that the number of measures made with the
Nicol prism was up to 1890 slightly under half a million.
Finally we have the more modest catalogue of Prof.
Pritchard, embracing 2647 stars, and, to complete the
record with this particular instrument, we must add a
small item of some 45,000 extinctions made at Harvard
under Prof. Pickering's direction. Of course, many stars
are common to all the catalogues, but the record shows
I that in the last few years instrumental photometry has
been applied to something like 30,000 stars. It is not
easy to form an adequate conception of so much activity.
But if the numbers have increased in such welcome
proportions, it may be asked is there an equally gratify-
ing advance in the accuracy of the observations .' This
question is not so easily answered. Doubtless there is a
much greater accord among the observations found in
the same catalogue, and made by the same observer,
employing the same instrumental means. But when
these catalogues are compared with one another,
large and provoking differences are sometimes en-
countered, and not a small portion of time has been given
by various astronomers to the investigation of these dif-
ferences, and the attempt to systematise the various re-
corded values of lustre. But when all has been done, there
still remain individual differences which baflleexplanation.
They seem to point either to irregular variations of bril-
liancy in the stars themselves, or to baftling meteoro-
logical influences, which it is impossible entirely to elimi-
nate. The suggestion has been made by others, and it is in-
tended here to give it the fullest support, that a far
larger number of stars exhibit variations of lustre than
are included in our variable star catalogues. It must be
remembered that these catalogues have been formed,
and the variations detected, by the eye alone— that is to
say, without the advantages of a photometer. Conse-
quently it is only the larger variations that have attracted
attention. It is not easy to establish the fact of an
alteration in brilliancy, if it be small, either with or with-
out a photometer ; but it seems not unlikely that as star
magnitudes gain in trustworthiness, a larger addition
will be made to the stars recognised as variable. To

;6o

NATURE

[April i i, 1895

come, however, to actual facts, it is recorded in the latest
published catalogue of magnitudes, that of Potsdam,
that the probable error of the concluded magnitude is
0"04 mag. This amounts to the same thing, practically,
as decidmg between the illuminating power of 25 and
26-candle gas. It is not known whether such a problem
would offer any ditYiculty to gas e.\perts, but even they
sometimes fail to gain full credence from the public.

Bat the record of photometric research is by no means
exhausted by this catalogue of work, limited to the
application of specially devised photometers to the stars
directly. Another and entirely different method of in-
vestigation has been actively prosecuted in the last few
years, and apparently with the greatest success. This
method avails itself of the refinements and the results
of photography. Every one knows the appearance of a
photographic plate on developing it after it has been
exposed in the focal plane of a telescope for a longer or
shorter time. It is seen that the circular images of the
stars impressed differ greatly in size, and it may be in
depth of deposit, according to the magnitude of the stars
impinging on the plate. Consequently, by appropriate
means of discussion we are able to determine the rela-
tive magnitudes of the stars themselves. And since we
have here to contemplate the measurement of a sensible
area, it miy not be unwise to recall the fact that the term
" magnitude '' of a star is strictly limited to its brilliancy.
Magnitude, therefore, in its accurate astronomical sense,
is not easy of definition ; difference of magnitude, in-
volving as it does difference of brilliancy, is, however,
easily apprehended, and it is a difference of magnitude
that IS sought to be determined by measurement of the
blackened area corresponding to the star images on the
sensitised film.

The problem here offered for solution is not precisely
the same as that in the direct application of a photo-
meter to the light of the stars. The eye ceases to be the
actual photometer employed. For the impression on the
retina we have substituted the impression recorded on
the photographic film. This film may be more or less
sensitive 10 some of the rays that go to make up the
whole of the light of a star than is the ordinary retina,
and consequently the record will differ in mdividual
cases from ihat obtained by photometric means in the
more ordinary sense of the word. Leaving out of the
question orlhochromatic plates, which are not usually
employed in recording the positions of stars, the films
are prepared so as to be most sensitive for the violet
light of a star, whereas the eye is generally most sensi-
tive to the yellow. If object-glasses arc employed, this
ditterence is usually aggravated again, for the optician
seeks to make this coloured light most operative, ac-
cording to the direction in which the telescope is to be
employed. In the case of a photographic telescope, the
rays about G in the spectrum are most important ; in
the visual telescope, those rays about D. In whatever
svay the photographic observations are discussed, with
the view of ensuring a general agreement with photo-
metric results, it must be anticipated that exceptional
cases will differ, especially when the star light is rich in
violet rays. Speaking generally, while a photometer, as
usually employed, seeks to arrange the stars according
to their appearance to a normal eye, a photographic
determination of relative brilliancy exhibits the stars as
they would appear to an eye most keenly sensitive to
chemical rays.

The method of deriving the photographic magnitude
will differ according to the manner in which the observa-
tions have been made. In the ftr^l place the ordinary
plate, whether it be taken with the view of producing a
general chart of the heavens, or the accurate representa-
tion of any small selected area on the sky, will contain
implicitly the magnitudes of the stars impressed. Con-
sequently, if we measure the diameter of the circular

N J. 1328, VOL. 51 ]

images produced by the stars of known magnitude, we
have a relation between diameter and stellar magnitude.
Such attempts end in the derivation of a convenient
formula of interpolation. We may find that an expres-
sion of the form m = a~ bd or /// = a-h log d (where m and
d are respectively magnitude and diameter and a and b
constants applicable only to that plate, and available
only through a small range of magnitudes) is serviceable
practically, but has no physical meaning. The determ-
ination of the constants a and b is troublesome, and
demands a previous knowledge of the photometric mag-
nitudes of some of the stars on the plate — information
not always at hand. 1-or these reasons attempts, more
or less successful, have been made to assign the magnitude
of a star from a knowledge of the diameter of the image
and the duration of exposure. To be completely success-
ful such an inquiry demands an acquaintance with the
manner in which the image grows on the sensitised film,
and this inquiry has progressed but slowly, and is still
incomplete. In the early <iays of photography, it was
supposed that the diameter varied as the square root of
the time of exposure ; later, with the modern dry plate,
the fourth root of the time was thought by some to mote
nearly express the rate of growth ; but I'rof. Turner and
the Astronomer Royal have both shown that neither of
the suggestions is satisfactory. The character of the plate,
the steadiness of the image, and the accuracyof "driving "
(that is, the successful removal of the effects of the earth
rotation), all enter as perplexing variables in a research of
this character. The Astronomer Royal has suggested
that the square root of the diameter of the photographic
image increases as the logarithm of the time of exposure.
This may be applicable to a particular telescope and
through a definite range of magnitudes, but is scarcely
likely to express a physical law. But, accepting such .1
result as a working hypothesis, we cannot pass directly to
the magnitude of stars without making another assump-
tion with regard to the diameters. This is usually
summed up in the expression that for equal diameters- -

Exposure x brightness = constant.

That is to say, in order to get equal diameters of the
images of two stars, one of which has four times the light
ot the other, we must expose the plate to the fainter star
four time? as long as to the brighter. This sounds
almost axiomatic, and was for a long lime accepted as a
demonstrated fact. So much so, that at the Paris Con-
ference in iSSy it was decided that the proper time of
exposure to photograph eleventh magnitude stars was
six and a quarter times that required for a ninth magni-
tude star. This decision of six and a quarter was
adopted because this number expresses the ratio of the
light in a ninth magnitude star to that in the eleventh.
Probably no great harm will come from the adoption of
such a resolution, but Captain Abney has given good
reasons for doubting the assumption that length of
exposure and intrinsic brightness are equally operative
in producing the same photographic effect. All this goes
to show that the determination of magnitude from an
examination of the small circular dots on a " star plate"
is not at all a simple problem. There is, too, anothci
fact which should be borne in mind. All the discs are
small, and yet in a range of five magnitudes, one hundred
times more light has gone to make up the l.iiger than the
smaller of the two discs. This means th.it the scale is
much contracted, and will probably interfere with final
accuracy, quite as much as a want of dcrtnilcness at the
edge of the disc, or distortion from a circular shape by
being photographed at a distance from the optical axi^.
or other c.iuscs which make the measurement of tliu
exact size of the blackened area, uncert.iin.

It is a question If the problem be materially simplified
when the plates are photographed with the direct
purpose of determining magnitude. We should then

Al'RIL II, 1895J

NA TURE

561

probably adopt a plan which has been extensively em-
ployed by Prof. Pickering, but so far has had few
imitators. This consists in photographing the trail of a
star. If we leave a phototelescope at rest with a plate
exposed, the stars describe circular arcs on the plate
having the pole as a centre, and having a length of 15"
for each hour of exposure. The lineir length will vary
according as the star is near or remote from the equator,
and since the energy is distributed over this varying
length, polar stars will produce more intense trails than
those stars of equal brightness near the equator. Kffec-
tively if two stars are found giving trails of equal den-
sity, the brightness of the two stars varies as the cosine
of the declination. But if it be found that the stars
near the equator travel, by reason of the earth's rotation,
so rapidly across the plate that the fainter among them
leave no trail, it is possible to give such a rate to the
driving clock that the trail may be of any definite
length, and the energy concentrated for a longer or
shorter time over this space.

The method of deriving the stellar magnitude from an
examination or measurement of these trails will be best
understood by considering the case of the polar stars.
A plate was exposed to the pole for ten minutes, and the
telescope left stationary. The aperture was then reduced
by successive amounts, so that theoretically any star
would appear one magnitude fainter. In the case of a
selected star, therefore, we have the thickness of the
trail corresponding to known magnitudes, which could
at once be compared with the trails formed on other
plates. Actually these trails, corresponding, it is pre-
sumed, to stars of known magnitudes, were brought into
juxtaposition with the trails of stars whose magnitude
was sought, and the brilliancy was decided by equality
of appearance. Of course similar practices could be
and have been pursued when the stars are represented
on the plate by means of circular discs. By varying
the length of exposure in the photograph of a star of
known magnitude, we can approximate to the appear-
ance that stars of any magnitude would present for
known durations of exposure. But here difficulties con-
nected with the sensitiveness of the plate, and the
meteorological circumstances of the night affecting tlie
transparency of the atmosphere, have to be taken into
the account, and the effects eliminated from the obser-
vation as carefully as possible, so that it is doubtful if
a higher degree of precision results than in the case
of photometric observation. There is, however, the
obvious advantage that the photographs remain, and
greater leisure and further experiment may suggest
improved meihods of observation and reduction, that
shall ultimately give us all the accuracy needed in inves-
tigations of this character. The process as at present
employed by Prof. Pickering appears to be fairly rapid.
Three or four years ago he could report that he had
applied his method to over 60,000 images, and the
accuracy appears to be about as great as in the case of
photometric observations. The chances of systematic
error are probably greater.

NOTES.
At Marlborough House, on Tuesday, in the presence of the
Council of the Society of .Vrts, the Prince of Wales presented
to Sir Joseph Lister, Bart., ihe Albert Midal accorded to him
by the Society for " The discovery and esiablishment of the
antiseptic method of treating wounds and injuries, by which not
only has the art of surijery been greatly promoted and human
life saved in all parts of the world, but extensive industries
have also been created for the supply of materials required for
carrying the treatment into effect."

NO. 1328, VOL. 51]

Prof. Christopher Heath has been elected President of
the Royal College of Surgeons, in the place of the late Mr. J.
Whitaker Hulke, F.R.S.

Dr. G. S. Buchanan has been appointed to the office of
Medical Inspector of the Local Government Board.

The Croonian Lectures at the Royal College of Physicians
will be delivered by Dr. W. Marcet, F. R. S., on June l8, 20,
25, and 27, the subject being the " Respiration of Man."

The grants lately made by the United States Congres.=, for
the Geological Survey during the fiscal year iS95-t;5, amount to
515,000 dollars, or ;^io3,ooo. This sum includes all field and
office expenses and salaries.

L.A.ST week, the colleagues and former pupils of Sir William
Turner, Professoi of Anatomy in the University of Edinburgh,
presented him with his portrait, ai a mark of appreciation of
his services in the cause of science and to the University.

In connection with the Goldsiniihi' Company's grant for
researches on the anti-toxin treatment, a Committee of the
Royal College of Surgeons of England have recommended a
grant of one hundred pounds to Dr. Sidney Martin, for the
purpose of working out the action of the ami toxic serum,
when used to counteract the effects of various poisons
separated by him from the membrane, and from the spleen, in
cases of diphtheria.

We have already noted that the London Chamber of Com-
merce are promoting a Bill for legalising the use of metric
weights and measures for export trade purposes. In connection
with this, the London County Council has just res jIved to do
all in its power to secure the passing of the Bill during the
present Session. In the meantime the Council's inspectors
will not interfere with the use of metric weights and measures
in the execution of foreign order.-.

Among the men of science who have died during the past
week is Iheodor Brorsen, whose name is so well known to
astronomers. He was born in 1S19, and was the discoverer of
five comets, as well as the author of a number of writings on
astronomical subjects. Since 1879, he lived in retirement at
Norburg, his native place. Mr. J. H. Greener, the constructor
of several early lines for telegraphic communication, and one
of the most able of practical telegraph engineers, died on
Sunday, in his sixty- sixth year.

The President of the German Meteorological Society has
issued invitations for a general meeting of the Society, to be
held at Bremen on the lyih, i8th, and 19th inst., when various
matters of interest to meteorologists will be discussed. The
time of meeting has been tixed so as to fall in with the geo-
graphical conference, which will be held at the same place
during Easter week, and in which oceanography and maritime
meteorology form a prominent part. Tlie subject of south
polar investigation is also included in the geographical pro-
gramme, so that it is anticipated that a large number of scien-
tific men will lake part in the proceedings.

The spring meeting of the Iron and Steel Institute will be
held in London on Thursday and Friday, May 9 and 10 next,
in the rooms of the Society of Arts. The presidential address
will be delivered by Mr. David Dale, and the Bessemer gold
medal will be awarded to Mr. H. M. Howe, who will contri-
l.ute a paper on "The Hardening of Steel." Mr. Stead, of
Middlesbrough, will contribute a paper on " The Effect of
Ar^enic on Steel"; Mr. Sergius Kern, Metallurgist to the
Russian Admiralty, will discuss the manufacture of armour-

^62

NA rURE

[Apkil 1 1, 1S95

piercing projectiles in that country ; >fr. Herhert Scott will
communicate a paper on the iron ore mines of Elba ; and Mr.
W.J. Keep, of Detroit, will contribute a paper on " Tests of
Cast Iron."

Prof. Dr. G. Schweixfurth, the distinguished African
traveller and botanist, has passed the winter at llclouan, near
Cairo, where be is engaged in mapping and describing the
adjacent mountains and " wadis," for a memoir to be com-
municated to the Instilut Egyptien. Dr. Schweinfurth h.\s
just published the text of an interesting lecture on Erythrsea
—the Italian colony on the Red Sea— delivered before
the Geographical Society of Berlin in July last year. This
paper gives an account of a four-months' expedition which
he made to Erythi^a' in the early spring of 1S94, in company
with Dr. Max Schoeller. It gives a most favourable report
of the progress of the new Italian colony and of its future
prospects.

A CORRESPONDF.NT has sent us particulars of an explosion
which occurred at Providence, Rhode Island, U.S.A., on
March S, in connection with the electric light mains of that
city. The explosion resembles those recently investigated by
Major Cardew (see p. 539). Through a leak in the gas mains,
the conduits became full of an explosive mixture, which
suddenly exploded with great violence. The street was blown
up for some thirty feet, all the glass in neighbouring houses
wrecked, and mis^'iles of wood and iron thrown to some
distance. The noise and shock are said to have been felt all
over the city.

The circumstances connected with the formation of the
dangerous alkaline deposits found by Major Cardew on the
mains of the St. Fancras electric light supply, and the presence
in this deposit in some cases of the alkaline metals in an un-
oxidiscd condition, have been inquired into by a Committee of
the Royal Society and the Institution of Electrical Engineers,
and the results have been issued in a report, which states that
*' the Committee are of opinion that the explosions which have
occurred were caused by the firing of an explosive mixture of
coal-gas and air by sparks caused by means of the above-
mentioned incrustation. It has been proved that sparks may
be caused either by the incrustation itself acting as an imperfect
electrical conductor, or by moisture coming into contact with
metallic sodium or potassium, both of which metals have been
found to exist within the incrustation. These metals have been
produced by the electrolytic decomposition of alkaline salts,
chiefly derived from ihc soil and conveyed by moisture
along the fibres of the wooden bearers towards the
negative conductor. To avoid a repetition of these accidents,
the bearers of the insulators at present in use should be replaced
by other devices through which moisture is prevented from
Iravellirg, and it is recommended that the pattern of insulator
in use should be changed, and a pattern adopted in which a
longer insulating surface is interposed between the conductors
and the bearer. The Committee are also of opinion that it is
desirable that means should be provided by which the conduits
can be inspected throughout their length, so far as is necessary
tn detect incrustations on the insulators. The Committee have
not thought it within their province to investigate the causes of
the presence of coal-gas within the electric lighting conduits,
but it is obvious that this is the primary source of danger."

Dr. Duprr's rcforl with reference to the recent explosion of
a cylinder filled with compressed oxygen, at Fcnchurch Street
.Station, was read at the coroner's inquiry List Thursday. An
examination showed that the inner surface of the cylinder was
fairly clean, but at the end on which the valve was, the surface

NO. I 328, VOL. 51]

wasincrusted with magnetic oxide of iron, which was easily re-
movable, and which under the microscope showed in many
places the globular form assumed by the magnetic oxide pro-
duced by the burning of iron or steel. The lower end of the
brass screw, by means of which the valve fittings were screwed
into the bottle, was also incrusted with magnetic oxide of iron,
much of which was in the form of small globules produced by
fusion at very high temper.ature. They were evidently fused to
the material of the screw, and it in some cases even slightly pitied
the metal. These facts lead Dr. Dupre to conclude, first, that
the bottle at the time of the accident contained an explosive
gaseous mixture ; and that, secondly, this mixture was fired by
so ne portions of finely-divided iron, or perhaps grease, igniting
in the compressed gas. That some iron had actually been on
fire in the cylinder the condition of the screw sufficiently proved.
The coroner, in summing up, spoke strongly in favour of a
Government let being imposed with regard to the cylinders;
and the jury included in their verdict the recommendation that
all compressed gases of an explosive nature should be scheduled
under the Explosives Act, that all cylinders should be tested by
the Government periodically, that no cylinder should be allowed
to be used or conveyed aboat unless bearing the Government
stamp, that all manufacturers should be licensed by the Board of
Trade in the future, and that separate hydraulic pumps should
be used in the apparatus in filling the cylinders, and also
recommended a Board of Trade and railway inquiry.

At the Institution of Civil Engineers, on April 2, Mr. J. I.
Thornycroft, F.U.S., and Mr. S. \V. Barnaby, in a joint paper,
expressed the belief that the speed of vessels had now ap-
proached within measurable distance of that at which propul-
sion by screws became inelTicicnt. For a given pitch-ratio and
slip, the thrust per unit of area varies as the square of the
speed. Certain conditions of pressure on the scre^vblades
cause the formation of caviies, filled with air and vapour
driven off from the water, behind the blades. Experiments
carried out by the authors, with screw-blades of elliptical
form, show that this "cavitation" does not commence sud-
denly, but appears to become detrimental when the mean
negative pressure on the forward side of the blades exceeds
about 6,' lbs. per square inch, or when the whole thrust exceeds
II J lbs. per square inch. Cavitation can only be avoided at
very high speed by increasing either the immersion of the
screw or its blade-area. Immersion is limited by considera-
tions of draught. Increased area, the authors remarked, can
be obtained in three ways : (i) by increasing the ratio of sur-
face to disc-area, (2) by employing a larger diameter than that
theoretically best for the given conditions, (3) by increasing
the pitch-ratio, which involves a larger diameter with a reduced
rate of revolution. Either tends to a waste of power if pur-
sued beyond somewhat narrow limits, and it appears inevitable
that reduced efficiency must be submitted to as the speed of
vessels is increased.

A I'EW noteworthy points were brought out last week in
evidence before the Select Committee of the House of CommoM
appointed to consider Ihc advisability of adopting the metrical
system of weights and measures. Captain II. R. Sankey, R.E.,
director of the engineering firm of VVillans and Robinson,
Thames Dilton, said that the metric system of measurement
had been adopted by his firm for the last two years. The
reason of the change was the advantage of working inter-
changeably with manufacturing engineers on the continent.
Mis firm's trade was mainly British, but no objection had been
made to metrical mcasurcmenls by Hrilish customers. The work-
men were agreed that the metric system was much more easy
to work with than the English measures, ard » as much less liable

April 1 1, 1895J

NATURE

563

to error. The inconvenience of the change to the metric system
was only felt by the workmen for a few days. In his evidence,
Dr. Gladstone estimated that in the elementary schools about 350
hours were occupied in teaching our cumbrous system of weights
and measures. As the children had to learn decimals, very
little more time would be needed by them for learning the
metric system. A chart explaining the metric system was now
to be found in nearly all the London schools, and lately it had
been decided to supply actual examples of the metre and litre
to such schools as asked for them. The metric system was but
partially taught in the schools, for the teaching involved
additional labour, and was not insisted on by the inspectors.
The introduclion of the metric system would be much facilitated
if the system were compulsory in the elementary schools.

In a paper read before a recent meeting of the Academic des
Sciences {Comptcs rendns, cxx. p. 611), M. Lucien Poincarc
described some experiments on secondary batteries he has been
performing. With a view of reducing the losses that take place
in the ordinary lead accumulator, the author has tried to obtain
a battery with liquid metallic electrodes. For this purpose
mercury has been employed, and as it would not do to employ
an acid as the electrolyte, since the hydrogen would be liberated
and thus cause a waste of energy, a solution of a salt is used.
Under these circumstances an amalgam is formed at the cathode,
which, together with the mercury of the anode, forms a second-
ary cell. Of all the different salts tried, the most interesting
results have been obtained with the haloid salts of the alkaline
metals. With these salts the electromotive force of the
secondary battery is about two volts, but in the case of the
chlorides and bromides, the chlorine or bromine combines with
the positive mercury, forming a badly-conducting layer, so that
the output of the cells is not satisfactory. With a solution of
iodideof sodium, however, very salisfactory results are obtained,
for as long as the solution is kept sufficiently concentrated, the
current density during the charging is not too great, and the
positive electrode has a larger surface than the negative elec-
trode, no djposit is formed on the anode. Hence by this
arrangement a secondary cell is obtained in which the two
electrodes remain, after the charge, entirely metallic, so that
the internal resistance does not increase as the cell is charged.
The efficiency of these cells amounts to very nearly 90 per cent.,
the electromotive force, when fully charged, being I '85 volts.
The capacity per kilogram does not differ much from that
obtained with ordinary lead accumulators, being about 10
ampere-hours. A very important point about this form of cell
is that the density of the discharge current is immaterial,
and they may be completely discharged without in any way
deteriorating.

We have received from Prof. G. Hellmann an interesting
pamphlet entitled "Contribution to the Bibliography of
Meteorology and Terrestrial Magnetism in the Fifteenth, Six-
teenth, and Seventeenth Centuries." The work was prepared
for the Report of the Chicago Meteorological Congress, and
contains a list and brief bibliographical notes of 272 old books
in Dr. Ilellm^nn's library, arranged under the authors' names,
with cross references under subjects and dates. This pamphlet
is of considerable value to meteorologists, as the early literature
of this subject is as yet little known, and no meteorological
institute is as rich in the older literature as the library in ques-
tion. Arranging the books according to the language in which
they were written, Ur. Hellmann shows that the authors com-
paratively seldom employed their native language, as 157 of
the works are in Latin. There is also a preponderance of
Italian works, as in the seventeenth century Italy probably
contributed more to meteorology than .all the other nations of
Europe. Many of the works describe! are exceediigly scarce.

Since the great Japanese earthquake of 1855, the strongest
shock felt in Tokyo was that of last June 24. No house was
absolutely destroyed, but in the lower parts of the city many
brick buildings were damaged and chimneys thrown down. The
total land-area disturbed was 42,000 square miles. The
diagram of the earthquake, taken by a large-motion seismo-
graph at Tokyo, is given by Messrs. Sekiya and Omori in a
short but valuable paper (Journ. of the Coll. of Science, Imp.
Univ., Tokyo, Japan, vol. vii. part v. 1894). This diagram
being on the natural scile, the preliminary tremors are not
shown, and during the first two seconds of the record the motion
was already strong. It then became suddenly violent, the
ground moving 37 ram., followed by a counter movement of
73 mm., the maximum horizontal displacement during the
earthquake. At about the same time, the maximum vertical
motion of lo mm. occurred. The movement, which lasted
altogether 44 minutes, soon became comparatively weak, and
it is no doubt to the small number of violent oscillations that
the slight amount of damage is due. As usual, the direction
of motion changed during the earthquake, but the maximuui
horizontal motion was directed towards S. 70° W. , and this is
identical with the mean direction of overturning of 245 stone
lanterns in different parts of Tokyo.

The Natural History Society of Queensland, established in
the beginning of 1892, has progressed so well that it is able to
issue a volume of Transactions. The volume should prove to
be a useful contribution to the literature on the natural history
of the colony.

The fifteenth volume of observations of " Rainfall in the
East Indian Archipelago," published by the Government of
Netherlands, India, has been received. The volume is edited
by Mr. Van der Stok, the director of the observatory at
Batavia, and it comprises observations made at 194 stations, of
which 104 are in Java and Madoera, and ninety in Sumatra and
the different islands of the Eastern Archipelago.

In the Geological Magazine for April appears a translation of
a Swedish paper by Prof. Lindstrom, on the discovery of
Cyathaspis in the Silurian formation of Gotland. In the cutting of
canals for the drainage of marshy tracts of the island, many good
exposures have been made of the [fossiliferous marl-shales that
underlie the famous limestones with the operculate coral
Khizophyllum. Among the fossils obtained from these shales
were a pair of dorsal shields of a Pteraspidian fish. Hitherto
the oldest known indubitable fish-remains date from the Ludlow
epoch, but the Gotland beds are of Wenlock age. It is pointed
out that since the vertebrate character of the Cambrian cono-
donts has been disproved,. and the supposed Ordovician fish-
remains of North America are very doubtfully of that age,
these Gotland fossils are, for the present, the ollest known
Vertebrates.

First among the new editions receive! within the past few
days is Prof. James Dana's " Manual of Geology," published
by the American Book Company. The appearance of this
fourth edition of Prof. Dana's classical work, makes us marvel
at the energy of the eminent author who, though now eighty-
three years of age, could rewrite the whole of the matter in such
a ponderous volume as the "Manual," and add one hundred
and fifty pages to what was published in the third edition. It
is hardly necessary to say that a multitude of new principles,
new theories, and new facts, in all branches of geology, have been
included in the new edition. "The Partition of Africa"
(Stanford), by Mr. J. Scott Keltie, has reached a second
edition, after two years of life. The many events that have
taken place in Africa during this time are all given considera-
tion. Another volume which has attained the eminence of a

NO. 1328 VOL. 51]

564

NA TURE

[April 1 1, 1895

second ediiion is "Outlines of Zoology," by Mr. J. A.
Thomson, published by Mr. Y. J. Pentland. The book has
evidently been oypreciated by students of zoologj- as a manual
for use in the lecture-room, museum, and laboratory. -Messrs.
W. H. Allen and Co. have published a third and revised edition
of "Practical .Microscopy," by Mr. G. E. Davis.

The lower sulphide of carbon, CS, appears to have been
obtained by Dr. Deninger, of the Dresden Laboratory, in con-
siderable quantities, .\nhydrous sodium sulphile and excess
of chloroform were heated in sealed tubes, fron which the air
had previously been removed, to a temperature about i8o°.
Upon opening the tubes after cooling a large volume of gas
was discharged, which consisted of sulphuretted hydrogen, a
small quantity of hydrogen chloride, and a new gas, which was
practically UDa6fected by passage through a solution of caus'.ic
soda. This gas was combustible, burning with production of
sulphur dioxide, and would appear to be carbon monosulphide,
produced in accordance with the following equation :
3Na,S -f 2CHa, = H,S + 6NaCl + 2CS.
The s.ime gas is obtained, less admixed with impurity, by heat-
ing in sealed tubes a mixture of silver sulphide and iodoform,
and subsequently allowing the product, consisting of carbon
monosulphide and sulphuretted hydrogen, to bubble through
caustic soda solution, whereby the latter gas is absorbed.

3Ap.S + 2CHI3 = II.,S T 6AgI + 2CS.
Kn analysis was made of the gas thus obtained, and the result
agreed with the f nmula CS. The gas explodes violently in
the eudiometer, so that analysis is not readily carried out
Tolumetrically ; the explosion pipette was destroyel in a second
attemp'. The action of sodium upon carbon disulphide was
next studied. When the metal is placed in the liquid disul-
phide it becomes coaed with a greyish substance, which pre-
vents further action. It was four.d, however, that aniline dis-
solves this coaiin', leaving the metal clean ; when carbjn di-
sulphide is th;n added, a continuon; evolution of gas occurs, but
the greater portion of the ga? does not e cape, being energetic,
ally absorbed by aniline, iiolcss \\\t sodium is maintained at the
surface of the liquid. After purification of the gas by passage
tlirough caustic soda, and through triethyl phosphine to remove
carbon disulphide, it is found to burn with a blue flame, with |
production of sulphur dioxide and water. The latter is owing '
to admixture of free hydrogen, which can readily be isolated
by absorption of the carbon monosulphide in aniline in a
Hempel burette. Carbon monosulphide is al-o rapidly ab-
sorbed by alcohol. Upon allowing the mixture of hydrogen
and carb in monosulphide to stream through tubes immersed in
a freezing mixture, the latter gas condensed to a clear colour-
less liquid, which rapidly evaporated upon removal from the
fieezing mixture. It would thus appear that carbon mono-
sulphide is a gaseous substance at the ordinary temperature,
but which readily condenses to a liquid in an ordinary freezing
mixture, is combustible, and is energetically absorbed by alcohol
and aniline.

The additions to the Zoological Society's Gardens during
the pajit week include a Feline Douracouli I^Nyctipilht<us
loci/traiis) from .South Brazil, a Squirrel Monkey (Chrysolhrix
■.<iurta.) from Guiana, presented by Mr. .'Vugusto Lewy ; a
King-necked Parrakeet (Paliiornis lor.jiiutut) from India,
presented by Lady Aitchison ; two Hybrid Widgeon (between
Marcca ftntloft, 6 , and Af. chilaiisis, 9 ), bred in England,
presented by Mr. J. Charlton Parr; seven Common Skinks
{Scincui offlcinalis) from the Sihira Desert, presented by
Major Sullivan ; a Ilaast'n Apleryx {Afteryx liaasli), an
Auckland NIand Duck {fl^tsontt/a aucilanJUa) from New
Zealand, nine Hamadryads {Of'hwphafiis flat's) from India,
deposited.

MO. 1328, VOL. 51]

OUR ASTRONOMICAL COLUMN.

The Lvrid Meteors. — Mr. Denning draws attention tothe
fact that ihisjear the Lyrid shower may he observed practically
in the absence of the moon. Though rarely forming a striking
shower, the stream is astronomically imp iriant for the rea-;on
that it is probably the only one, besiles the Perseid-, which has
its radiant displaced on successive nights of observation. The
duration of the shower is Irom April 16 to 23, with a maximum
on the 20th, and the displicement of the rad ant is com-
paratively small. On .-Xpril 20, the radiant is miniated in R A.
2/0% Decl. + 33°, that is, about 1° N. of 104 llerciili-, a st.ir
ol the 5th magnitude. Like the Perseids nf .-Vugu t. the Lyiids
never fail to show themselves, though they are rarely to be
comr'ared with the Perseids in point of richness (Oi/<Tz'a/.;/y,
April). The orbit of the swarm is probably identical with that
of Comet I, 1S61.

.\ New Form of Zenith Telescope — The determination
of the zenith distances of stars near the zenith appears likely to
be greatly simplified by an arrangement recently devised by M.
Louis Fabry (Bulletin Ailronomiqin, April). The main idea
is to materialise the zenith point so that micrometric measure-
ments can be made directly in the field of view. A horizontal
telescope is fixed in the meridian, and in front of it is a thin
sheet of glass inclined at 45" ; beneath this is a basin of mer-
cury. When adjustel so that the reflected image of the cross-
wires is coincident with the wires themselves, the wires m,ark
the zenith point, and stars of sufTicient briijhiness will also be
seen in the field of view after transmission through the glass anj
subsequent reflection from the mercury and glass. The gteat
objection to this simple plan is the reducion 1 f brightness of
the star images, and there is also an objection to observmg
stars after reflection from mercury. To overcome these difli-
culties, a second telescope is directed towards the first, so that
the cross-wires can be seen at the centre of the field, an I the
sheet of glass is coated with silver to a thickness that will juu
allow the strongly illuminated cross-wires of the *irst telesco|)e
to be seen in the second. The first telescope thus serves the
purpose of maiking the zenith point, and this is utilised in the
second telescope f-T the tueisurement of dis'ances.

Ascompated with the zenith telescopes in common use, the
new instrument has the advantage of greater smiplicity and
rigidity, and it is unnecessary to make differential measures of
stars north and south of the zenith. It should especially b; of
use in such an investigation .is that of the variation of latitude.

The Orion Nebula. — An exhaustive discussion of the
photographs of this nebula, and of the stars in its vicin tv, taken .
at Harvard and elsewhere, has been recen'lv completed by
Prof. W. II. Pickering (.-/MmrA </ //;<r Hanard C. liege Obstr-
valory, vol. xxxii. pa t I.) 146 stars have tieen catalogued, in
addition to those given by Bond for the same area, an i a com-
parison of magnitudes suggests that a few of the stats are
cither variable or have increased in brightness. No clear indi-
ca'ions of change in the nebula, either of shape, po-ition, or
b illiancy, have been detected in the phoographs taken during
the last ten years. By the ingenious artanijement of photo-
graphing the nebula thiough a thin perforated >heet of brass
placed in contact with the sensitive film, Prof, dickering has
constructed a chart of ihe nebula showmg isopholal contours,
or lin-s of equal photographic inter sity, which will be verv
valua'ile in s ibsequent >carch'ng for evidence of C ange. .V
photograph of the spec rum of thenebuli taken with the ob-
jective prism shows at a g'ance which regions shine with light
of any pati^nar wavelength. The image corresponding to
Ihe hydrogen line II7 is seen to resemble most closely the
ordin.iry photographs, while the ultraviolet line at A 372 is
found particularly strong along the south-ea-t border ol the
Huyghenian region. Among the photogra hs reproduced,
thai showing the v.ast llebulo^ity which nciily >urroun Is the
whole con-tellation of Orion is, perhaps, of ttie greatest
interest. This was taken with a portrait lens of about 2.1 inches
aperture, and shows the nebulous stream, about 15 ilegrecs in
diimeter, which has since been photographe I by Prof Hainnrd
(Nature, vol. li. p. 253). Prof. Picke ing gives rcas ms for
.supposing that the parallax of this remirk.ible nc'nila is not
greater than o"oo3, corre ponding to a di tance of i< 00 light-
years. A use'ul account of ihc fiindimcit.il princi|ilcs and
proce-scs of astronomical photography, including the deter-
minition of photo.;raphic stellar magnitudes, is given in the
same volume of the Ainiiils.

April i i, 1895 ]

NA TURE

565

>?,

THE SUN'S PLACE IN NATURE}
III.
n^'HE next question that we have now to consider has lo do
with the connection between nebula: and stars, and I shall
show that the more the facts are studied the closer does this
connection prove to be. ^'o^l remember thtt that was the idea
which lay at the bottom of the hypotheses both of Kant aul of
Laplace. In the last lecture I referred to s )me of the earliest
obgsrvtttions which hail been made of the nebuloe by means of
spectroscope, and it so happened that Dr. Hujjgins, to
whom we owe this work, came to the conclusion that the result
of his inquiries was rather tn shjw that this connection, which
had been asserted both by Kant and Laplace, and which had
been accep'ed by everybody up to then, really did not exist.
In a paper which detailed these spectroscopic observations,
published in 1865, Dr. Muggins stated his conclusion that the
nebula;, instead of having anything whatever to do with any
evolutionary line along which both nebula; and stars might be
traced, possessed a structure and a purpose in relation to the
universe altogether distinct and of another order. So that you
see the first apparent teaching which we got from the spectro-
scope practically put us in a very considerable difficulty; if it
had to be accepted, of course llie views of Kant and Laplace
would have to be rfjected.

When I commenced my general survey in 18S7, this view held
the field, and further, it was imagined that the observati ms of
Dr. Huggins justified the idea that the nebula were masses of

of these singular bodies, the nebul.-e, and the simplicity of their
composition, one is led to see in them only the residuum of the
primitive matter after condensation int > suns and into planets
has extracted the greater part of the simple elements which we
find on the earth and chemically in some of the stars."

It was perfectly clear then to Dr. Wolf that, if the con-
stitution of the nebulK was anything like what was supposed
to have been revealed by early spectroscopic observation, we
were dealing with a residuum. There was one kind of action
in space, bringing together one class of elein-nts with which
we are fimiliar here, and forming them into stars, suns, and
planets ; but there was another kind of matter which declined
to form part of these aggregations, which remained by itself,
and finally put on the appearance of the so called nebulx.

The first thing I have to say concerning this view is, that
the discussion of the spectroscopic ob-ervations which I told
y)u, in the last lecture, had been undertaken with a view of
seeing what really could be determined in relatio.i to this
question, showed, beyond all ques'i m, that there was no
ground whatever for it ; that tliere was no real ground for sup-
posing that there w.as this enormou; difierence between the
nebula and the stars. In the year 1887, the year following the
course of lecture-; to which I have already referred, after test-
ing the views on this question by an appeal to all the available
observations, I stated that the facts taken in all their generality
showed that the nebulae simply represent early stages of
evolu'ion ; that is to say, that we have a continuous and
orderly progression from the nebulae to the oldest star, and

Fig. 12. — Spectrum of the nehula inlAndromed.-i conipiired witli Nuv.t .'\n(lromeda; and comet. The tlutings common lo .ill ate those of carbon.

gas ; what particular gas will concern us a little later on, but for
the moment I need only say that these staletnents announcing the
nebulae to consist of one or two gases, at once led lo several most
rcnarkable views of the general constitution of the heavens.

Near the end of this nineteenth century chemists claim to
know something of the materials which have built up the planet
on which we dwell, and if you consult any of the books which
have been written about spectrum analysis, giving the results of
the work during the last thirty years orso, you will find it stated
over and over again that the spectroscope has put it for ever
beyond doubt that the chemistry of the skies, i.e. the chemistry
of the various bodies which people space, and which are at a
sulTicienlly high temperaiure to enable us lo examine them
spectrosc 'pically, exactly resembles the chemistry of the earth.
So that, il this were true, we should have a common chemistry
of the earth, of the stars, and among the star> of course our own
sun. On the other hand, we should have, according to Dr.
Huggins, absolutely and comidetely distinct from these bodies
another class, the nebulie, in which the chemistry is absolutely
&nd comfiletely unicjue. This was so clearly the idea suggested
to philosophical students of these questions, that Dr. Wolf, a
famous I'Veiich astrono ner, who has written an all-imp>rlant
book for those who are interested in these inquiries, " Les
hypotheses cosmigoniques," pulilished in 1SS6, writes: "If
we admit the data of spectrum analysis as to the gaseous state

' Revis-d fr.^ n tSorttiind n 'tes of a course of Lectures 10 W irking Men
At the Museum of Practicil Geology during November and December,
t894. (Continued Irom page 39;.)

that the nebulae represent the first stage, and the oldest star or
planet represents the last. It seemed to be perfectly clear from
the discussion that we were justified in stating that every
nebula which is visible now will some time or other, owing to
the condensation of its various parts, become a star of some
order or another ; and that it is equally true to say that every
star which v\e see now in the heavens, knowing it to be a star,
has really been a nebula at some time or another.

I told you that the first suggestion of a possiblecondition which
would enable an evolution to take place from nebulae to stars had
been made by Prof. Tail, when he thought that probably cool
meleoriiic particles might have something to do with it. The
complete inquiry shows that these meteoritic particles might
account equally well both for the luminosity of comets and of
nebula;. This association is important because it is generally
conceded that comtts ate swarms of meteori'es.

It seemed so obvious that there was this close connection
that in 1888 I predicted that, if the nebul.x were carefully ob-
served, we should find in them sooner or later indications of
that same substance which makes the comet's spectrum so very
distinct and special. In almost every comet which has been
observed, the spectrum of carbon, or of some compound
of carbun, is the strongest and most obvious feature
which is presented to us. In 1SS9, i.e. only the next year,
matters were made very much clearer by the discovery, by Mr.
Fowler and Mr. Taylor, of the spectrum of carbon in the
neliula of .\ndromeda (Kig. 12), so that there, you see, was a pre-
diction verified, and such verification is always a very precious

NO I 32S VOL 5 l]

;66

NA TURE

[April 1 1, 1895

test, since it helps us to know whether one is going right or wrong,
and it seemed to strengthen very much the view under con-
sideration. Further, not only do we find carbon both in
comets and nebulx but it is recognised by
everybody that in some stars the same substance
exists in enormous quantities. Here, then, we
are in the presence of the fact that the s'ate-
ment that there is an enormous chemical differ-
ence in structure between nebulae and stars is
shown spectroscopically to be unfounded, while
the evidence also goes to show that there is a
close connection between nelmlje and comets.
By this, of course, the argument is very much
strengthened all round, because, as wehaveseen,
nearly everybody agrees that comets most pro
bably consist of meteoritic stones or particles.
I am glad to say that among the first to
accept the new evidence proving that nebulje
are really early stages of evolution of stars
was Dr. Huggins himself, the otiserver whose
statement which I have quoted I had been
fighiing for years. That you see was a great
victory. He says now not only that these
bodies may represent early forms ; places them
in the line of evolution where 1 had placed
them, but he even adduces the same evidence
•which 1 had brought forward in several of the
arguments which 1 had employed. Dr. Huggins
made a reference to this que>tion as President
of the British -Association in the year 1891, and
if any of you read that you will see that it is
really an argument in favour of the views that
I have been insisting upon since 1S86, and his
agreement seems all the more important since
Dr. Huggins appears to have arrived at these
conclusions quiie independently. Not one' word is said
throughout the address of any arguments which I may have
used, or of any line of thought or observation on which I had

course you will acknowledge that that was a very extra-
ordinary change of opinion, so extraordinary indeed that
it is clear that Dr. Huggins felt that it was of importance

KlG 14. — Oljserv.ilion ol a 11 ■

founded the various statements which I had made ; ami there-
fore it would be charitable tosupposc thai he was unacquainted
with my work when that address was given to the world. Of

NO. 1328, VOL. 51]

Fic. 13. — The nebula near 52 Cygni, from a photograpti by Dr. Koberis.

to himself that the change should be explained ; and he con-
fesses in the address, to which I refer, that the communication
he made to the Royal Society in 1S64 was not entirely

founded on scientific
evidence, but pari ly made
under, to use his own
words, "the undue in-
fluence of theological
opinions then widely
prevalent."

So afler all I had
lieen fighiing partly
an expression of a
iheological opinion. If
we had known that
hefoie, proliably some
trouble might have been
saved.

It is a very important
thing to know that now,
from east to west, those
who dwell upon this
planet are all perfectly
convinced that nebuls
are e.irly forms in the
tvoluiion of ihe heavenly
bodies. The more one
knows of ihe history ol
luiman thought, espe-
cially during the last two
.enluries, the more im-
(Hjriant does it seem that
1 hat result should be ac«
knowleilgtd as oneof the
most important truths
rsiahlished during the
|irtscnt century.

Ik' fore 1 go further,
let nie refer to two or
three lypical examples of
these Mrange bodies, as
I can do by ihe kindness
of Dr. Roberis, whose method of woik I described in the last

lecture. . f u i_

First of all we have a representation of a form of nebuW

April i i, 1^95]

NA TURE

5&7

which is not very common, but the study of which is all im-
portant for our present purpose. It is called a spiral nebula,
it is one of the nebulre: in the constellation of the Great
Bear. I wish to point out that in the centre we have a
condensation, and from the centre of the condensation the
luminosity gradually gels less and less until at last we have
no luminosity greater than that of the surrounding sky. In
the nebula itself we find exquisite spirals, starting apparently
from different points, and gradually coming towards the centre,
and if you look along these spirals you will see that the star-
like masses, which may not be stars, are in many cases located
on the spirals, representing apparently minor conden-
sations, each spiral itself being probably brighter than
the other parts because it is more disturbed.
Next we have an absolutely unlouched photo-
graph of the famous Dumb-bell Nebula. I am
certain that many here have studied the drawings
of this nebula given in encyclopedias and in
books of astronomy during the last forty years,
and that it is a great comfort to you to see, as ii
is to me to be able to show you, the autobio-
graphical account that it gives of itself, because
if you refer to those drawings it will be very
difficult to find any two alike, even if it is
distinctly stated that one has been copied from
the other. In this again we find a central con-
densation, and associated with it arcs in which the luminosity
is greater than in the adjacent regions.

The other nebula that I have to exhibit is one remarkable for
its difference from the other two, inasmuch as no condensation
is suggested. This nebula, which you see stretching across the
screen like a sort of celestial river (Fig. 13), seemsto be careering
through space, and I call your attention specially to this because
it is well to remember that, if we have meteoritic swarms in space,
i.e. swarms which are condensing, it is quite possible that «e
may have meteoritic streams. I think you will consider that it is
not any misuse of words to say that we have there a possibility
of a meteoritic stream.

So much then for some typical representations of some of the
different forms of nebuloe.

While, however. Dr. Huggins in his presidential address,
apparently from quite independent inquiry, announced my main
contention, viz. that nebulse and stars do belong to the same
order of celestial bodies, and withdrew his unfortunate state-
ment as having been made on theological grounds, I am compelled
to say, but wish to say it with the utmo>t courtesy, that a com
plete study of the literature shows that he was quite familiar
with my work all the time, and that while he thought fit to re-
publish my main contention as his own on the one hand, on the
other he was engaged in attempting to throw discredit on my
work, and to conceal his retreat after the manner of the sepia by a

I propose to go into this matter in some detail, because it will
enable me to indicate the closeness with which the skill of
trained observers and the magnificent instruments of modern
research that I have already referred to, enable us now to
deal with facts, and to replace the imperfect observations
of the past with others of which the accuracy may be relied
upon.

Among the many lines of evidence which had been brought
forward, it was stated by myself that in following up the
suggestion of Prof. Tait and experimenting upon meteoritic dust,
a line had been seen very near the position of the chief line which
Dr. lluggins had discovered in the year 1864 in the spectrum
of the nebulae. In fact, after accumulating all the spectroscopic

l^ic.

-Line-spectr.i 01 bariutn and iron.

Iron.

great cloud of ink— printer's ink, referring to a minor
point. He endeavoured to suggest to anybody who was not
really completely acquainted with my work, that the methods
employed by my assistants and myself for something like
three years were inaccurate, and that the conclusion
reached, which must have bnen right because he had come to
agree with it, had been got at in the wrong way. Alihuugh
the charges of inaccuracy which Dr. Huggins thought lit 10
make were general, in his printed papers the chief stress hss
been laid upon a statement I had made with regard to a
nialter of secontlary importance in the general discussion, I
refer lo the possible origin of the chief line in the nebular
spectrum.

NO. I 328, VOL. 51]

Fi-;. 16 — Fliitingsof c.aibon.

observations which I could lay my hands on, I went on to
experiment myself, and I have here some apparatus which
will give you an idea of the kind of experiment which was
undertaken (Kig. 14.) Meteoritic dust is placed in a horizontal
spectrum tube connected with a .Snrengel air-pump, so that an
electric spark can be passed through the dust ; an image is
formed on the slit of the spectroscTpe, and an arrangement for
an ordinary electric spark in air serves for a comparison
spectrum. The point was to see whether there was any
probability that Prof. Tail's suggestion was right, by examining
the spectrum of meteoritic dust. For this purpose some dust
was placed in a tube resembling the one now on the table, and
an electric current v/as sent through it. Now it had long been
known that when one heats meteoritic dust, it gives out com-
pounds of carbon, and also hydrogen gas ; what I did was to
observe the change in the spectrum of that tube under different
conditions. For instance, if it were wished to expose the
dust to a higher temperature, a liunsen burner was placed
underneath it.

Vou will be able to see that, in a little time, the heat will make
a considerable difference in the phenomenon observed in the
region which comes under its influence, and I think you will
also see that in some parts we get a distinct indication of green
colour. Now what I found was that in the spectrum of dust
from several meteorites so examined, there was a line very near
the position which had been stated by Dr. Huggins to represent
the aclual position of the chief line seen in the spectrum of the
nebula;. That line I was able to trace home by comparative
work to olivine, a substance which occurs in almost all meteor-
ites, even in iron meteorites, and not only to olivine, but to
one of the constituents of it, which is magnesium. I have here
a diagram of some of the results obtained in the green part of the
spectrum, and it will be setn that we get in the nebula of Orion,
and in the comets of 1S66 and 1886, a bright line apparently in
the same position. When I say line I should correct myself,
this luminosity given out by magnesium does not take the form
of a line as ordinarily so called. I will throw on the screen
photographs of two spectra of the vapours of two metallic
substances, barium and iron (Fig. 15), and you will then see
what is meant by men of science when they talk about a line
spectrum.

But besides what we call line spectra, there is another
thoroughly well- recognised class, which we call fluted spectra,
because it reminds one of the flutings of a column. Here, for
instance, is a fluting of carbon (Fig. 16). In these flutings,
instead of the lines being distributed irregularly, as in the case
of iron and barium, we get a beautiful rhythm from one part
where the light rapidly degrades to another where there is an
enhancement of the light, followed by another degradation, and
so on. Indeed, we not only get main flutings, but we get
subsidiary flutings.

J. Norman Lockyer.

( To be conlinved, )

S6S

NA rURE

[April i i, 1895

THE I.XSTITUTION OF NAVAL

ARCHITECTS.

'T'HE annual spring meeting of the Institution of Naval
■*■ Architects was held on Wednesday, Thursday, and Friday
■of last week, in the theatre of the Society of Aits. There was
a long list of papers set down for reading and discussion as
follows : —

"Noies on further Experience with first-class Battle-ships,"
by Sir William White, Director of Naval Construction.

" The Elements ol Force in a Warship," by Vice- Admiral
P. H. Colomb.

"On Steam Pipes," by J. T. Milton, Chief Engineer Sur-
veynr. Llo)Hs' Retjistry of Shipping.

" Light Draught River Steamtrs," by George Rickard.
" On solid Stream Forms and the Depth ol Water necessary
to avoid abnormal Resistance of Ships," by D. W. Taylor,
Senior Assistant to Chief Constructor of U.S. Navy.

" On the Method of initial Condensation and Heat W'aste in
Steam Engine Cylinders," by Prof. R. H. Thurston, Sibley
Collrge, Cornell University, New York.

" De-cripiion of an Aluminium Torpedo Boat built for the
French Government," by A. F. Yarrow.

"On Vibrations of Higher Order in Steamers, and on
Torsional Vibrations," by Otto Schlick.

" On the Vibrations of Ships and Engines," by W. Malloek.
"On a Method of Extinguishing Vibrations in Marine
Engines," by Mark Robinson and H. Riail Sankey, Captain
(retired) R.E.

"On the Transverse Stability of Floating Vessels containing
Liquids, wiih special Reference to Ships carrying Oil in Bulk,"
by W. Hok.

" Induced Draught as a Means for developing the Power of
Marin- Boilers," by W. A. .Martin.

Alter the usual formal proceedings had been transacted, and
the President, Lord Brassey, had given a brief address. Sir
William White's paper w.is read by his colleague at the
Adojiralty, Mr. W. E. Smith, the author being absent owing
to serious illness ; from which, every one will be glad to hear,
he appears in a lair way of recovery. This contribution dealt
chiefly, indied almost wholly, with the question of steadiness
in the laige ba' tie ships of the Royal Soverri^n c'ass, and
the effect of fitting them with bilge keels. This paper may
be said to he the complement of another memoir by the
same author, read befire the Institution last year, in
which the experience gained with the big line of battle-
ships was recortled. Win n the Royal So-uerngn was designed,
it was thought th.it the period of oscillation would approximate
to that of the Inconstant, Herctila, and Sultan, which were all
remarkalily steady ships. Tiie Hercules and Sultan had only
shallow side keels from 9 to 10 inches deep. It was thought
that the great inertia due to the large dimensions of the new
^hips would lender them so sttady that these small bilge k- els
might be omitted. That the expeclaions formed in this respect
have not been fulfillid, shows that even the best-informed naval
archiiecis, even when supported by the best scientific evidence
at their command, may l)e wrong at times. The performance
of the ships of the Royal Sovereign class at sea led to the fiiting
of bilge keels to oi.e ot them — the Repulse. These keels are
«ach about 200 feci long and j (eet deep. Four of the class
were at s-a off ihe west coast ol .Soolland in company. There
was a lorg low swell, 300 lo 4C0 feet from crest to crest, and
with afxriod of about ten to twelve seconds. The Resolution,
without bilge keels, rolled 23, and the Repulse 10. The sea
was on the quarter, and the speed such as 10 produce heavy
rolling. The iccoids of angle of roll were obtained by ihe
pendulum, an in>tiument notoriously untrustworthy, but in the
proem case the rtsults quoted wire probably fairly accurate.
At any rale, there was noiloubi that the behaviour of the ship
was iiomensely improved by the bilge keels, and it was decided
10 fit all other shipt ol the class in a similar manner to the
Repulse. I he consen-us of ^pinion o( naval oilicers is thai roll-
ing has bc<n grratly reduced. Sir William While very frankly
admits that the steadying elTect of bilge keels has grei'ly ex-
cetded that which wa> anticipated ; and, indeed, the o|jinion of
naval architects ai large will now have to be rcvljus el, and
the data upon which ship designers work will require lo be
modified. Fur scientific pui|>ose« more exact information wai
required than could i>c obtained by trials at sea, on which, as is
well known, it Is generally imfxissible to obtain accurate records.

It was therefore arranged that still-water rolling experiments
should be made with the sister ships Revenge and Resolution.
Mr. R. E. Froude, whose father's work is so well known in this
field, had charge of these trials. One series of experiments was
made before bilge keels were fitted, and another alter the
keels had been attached. Each series was divided into two
sections, the ships having a metacentric height of 3} feet
in one case, and a little under 4 feet in the other. The
conditions approximate to those of maximum and minimum
stability on service. The oscillation of the ships was
produced by training the heavy guns and running men
across the deck in the usual way. The results of these trials
were shown by means of diagrams hung on the walls of the
theatre. Curves for the older ships Sultan and Inconstant were
also placed on the diagram. Starting from an angle of inclin-
ation of 12° from the vertical, it was seen that in order to reduce
the corresponding inclination of 6°, the Rezenge, without bilge
keels, required to make 18 to 20 swings, and the Sultan about
17 ; there being a remarkable similarity between the curves of
declining angles of the two ships. The Sultan, as already
stated, has always been considered a satisfactory vessel in regard
to steadiness. Starting from an angle of inclinatiotr ol 6'
from the vertical, it required 45 swings in the Acvenge without
bilge keels to reduce the corresponding angle ol inclination to
2°. After hilge keels were fitted, an equal reduction was
obtained by only 8 swings. For the. Sultan and inconstant,
32 lo 20 swings respectively would be required to produce the
same reduction. Ihe Revenge, before the bilge keels were
fitted, could be rolled up to an angle of inclination of 13° to
the vcitical by moving her barbette guns. Alter the keels were
in place it was dilficull to exceed an inclination to the vertical
of 6° to 8°, even with 300 to 400 men running .icross the deck,
and acting in c )njunction with the movement of the guns.

The variation in the periods of swing (from out lo oat)
brought to light by these trials are insiructive. Without
bilge keels, the author continues, the rolling was practically
isochronous at large as well as small angles. The period for a
single swing was 76 seconds for maximum stiffness, and 8
seconds for minimum stiflness, for large as well as small arcs of
oscillation. With bilge keels, within the r.inge of experiment
up to a swing of about 12° (6° each side), the period of a single
swing decreased as the angle of inclination became smaller;
the reduction being about 2^ per cent, in going from a mean
inclination to the vertical of 5° to one of 1°. When the meta-
centric hcighis and radii of gyration of the ship were appreci-
ably unchanged, there was an increase of about 5 per cent, in the '
period due to the action of the bilge keels.

A study of the action of bilge keels on a chip's performance not
only involves questions of the greatest practical importance to
the >hip designer, but also problems of high scientific interest.
From whichever point of view we consider Sir William White's
paper, it is one of exceptional value. It i^ seldom lh.it the
naval architect has the opportunity of mnking trials or experi-
ments on so grind a scale as that afforded by the big battle-
ships of the Royal Sovereign class, and lor this reason we are
giving unusual space to this jiaper. Ne\ertheless, we are un-
able 10 follow the author in his comparison of the experiments
undc' consideration with those jireviously made both by I''rench
and English engineers. For the>e we must refer our readers to
the original memoir, confining ourselves to the main results, from
which a comprehensive view of the scope of the paper may be
formed. One of the most impoitant of these results is the
increased extinctive effect shown by ttie experiments lo be pro-
duced by bilf^c keels when the ship has headway, compared 10
ihe elTect when she is not progressing. The experiments under
way were limited in number, and, as the author points out, are
peih.ips not so definite as those with the .-■hiii not having head-
way. " Still they are very suggestive," to once more quote ihe
author's woids, "and confirmatory ol the concluson fiom pre-
vious experience that the rale of extinction is sensibly increased
by headway, the ship eniering uniiislurbed water while oscil-
lating, and the inertia ol ihal unoisturbtil water having to he
overcome." We can only quote the broad results. Slnrting
at 5 from the vertical the angle-, of inclination reached,
alter a ceitain number of swing-, were as follows : — Alter 4
swings, ro headway 295,81 10 knots 235, at 12 knots
22°. After 16 swings, no headway 1'I5', 10 knots ^o", li 1
knots '25 .

It will be remembered by students ol this subject that ihe
late Mr. Froude assigned a coelhcient of lesistance of 16 Ibi.

NO. 1328, VOL. 51]

April ii, 1895]

NA TURE

569

per square foot for deadwoud and keels moving at I foot per
second, and ihis was c infirmed by the behaviour of the Saltan.
Accepting Mr. Kroude's formula, the extinciive effect due to
bilge keels, such as have been added to the Rrjuige, was
calcula'ed, with the result that, in an extreme case, supposing
the ship to he rollinu; to 20^ an each side of the vertical, the
extinction value due to the bilge keels would appear to be not
quite 2'. Thi-, it will be seen, is far shoit of the observed
results obtained from the vessels themselves. Working on the
data that have been obtained in this way, new coefficients have
been calculated for bilge keel resistance, it being assumed that
the whole increase of work were credited to the bilge keel area.
For an angle of swing of about 10' instead of the coelTicient
being l '6 lbs., it woul I be about it lbs for a swing of 4' the
coethcient would reach as high a value as 15 or 16. It muit be
remembered that these coefficients are not put forward as truly
representative, they only hold good if the assumptions stated
are accurate.

In any case the dilTerence is very great. Mr. R. E. Froude,
who conlributcJ a most interesting speech to the discussion,
confessed that the results took him, when he first had them
put before him, entirely by surprise, and, indeed, he did not
credit the statements made as to the improved behaviour of the
ships ; or, rather, he could not attribute this improvement to
the presence of the bilge keels. We judged, however, from
his remarks tliat he now accepts the observed data and the
truth of the recorded experimental conditions, but still con-
siders the phenomenon one for which he can offer no a-iequate
explanation. He hi nself had made tank experiments which
agreed /airly well with the results obtained by his father, and
was quite at a loss to account for the great difference between
these experiments and the results of the trials niw recorded.
The only explanation he could suggest was that bilge keels, on
a rolling ship, meet on the return roll with water set in motion
by the previous roll ; but this, he thought, was quite insufficient
to account for an increase in resistance of as much as, say, ten
times thai which would be calculated on the i'6 coefficient.
Naval architects will be glad to hear that the whole question is
to be madethe subject of exhaustive inquiry at Hislar. The prin-
cipal reasons that bilge keels are not fitted — putting aside expense
and difficulties as to docking — are that they add to the immersed
surface, and are thus likely to decrease speed. It is, therefore,
satisfactory to learn that "the practical tests of actual service
prove there is no sensible reduction in speed for power." As
it is also -tated that the keels have not sensibly reduced diameter
of circles made by the vessels, and, further, that additional
steadiness m sttering has been obtained, it is not hazarding
much to say that in future ships of this class in the Royal Navy
will all be fitted with bilge keels, unless exigencies of docking
forbid their application.

The space which we have devoted to Sir William White's
paper will compel us to dismiss most of the other contributions
briefly. Mr. Milton's paper on steam-pipes was an excellent
practical contribution, and was followed by a no less excellent
discussion. The general conclusion arrived at appeared to he
that , with high piesure, steel steam-pipes are likely to take
the place of those of copper. Mr. Taylor's paper was read in
brief abstract, and as it was not in the hands of members until
a few minutes before the meeting, we must pass it by. The
same thing may be said of Fruf. Thurston's paper. It is very
gratifying to the members of an English institution to receive
papers from foreign members of such eminence as the two
American gentlemen just mentioned. We regret we have not
yet been able to devote the time to their contributions which
their merits doubtless demand. Mr. Yarrow's paper on the
aluminium torpedo boat he had built for the French Government,
was a very interesting contribution. The boat appears to have
been thoroughly successful, so much so that she is to be the
prototype uf a class. The discussion turned largely on the form
of test pieces for copper alloys, it being generally conceded that
there is a want of standard conditions for tests. The micro-
sections of various alloys thrown on the screen were also very
interesting.

The last day of the meeting (Fiiday) was devoted chietly to
the vibration question, the sitting proving one of the most
instructive of the series. .\> will be seen, three papers were
contributed on this important and interesting suliject.

These ttiree papers on vibration of steamers formed, with Sir
William White's paper on steadiness, thet.>o distinciive features
of the meeting. It is hardly necessary to insist on the import-

NO. 1328, VOL. 51]

ance of these two features ia steamship performance, both
of which affect alike the comfort of the passenger in
mercantile vessels, and fighting efficiency in a war vessel.
Since engine piwer has increased so greatly and speeds
have been raised, the vibration question has become one
of extreme importance in passenger steamers. Two of the
most recent largest and costliest of our ocean liners were almost
unfitted for carrying passengers — it any rate, they were fast
acquiring an uneviable reputation — on account of excessive
vibration. By the application of scientific principles the cause
of this defect was traced, and the evil cured ; a circumstance,
if measured by money value, now worth many thousands of
pounds to the owners. The extremely interesting paper and
series of experiments performed two or three years ago by Mr.
Yarrow, at a meeting of this Institution, will be remembered by
our readers ; and since then llerr Schlick has read two papers
on the su'iject. Records of these will be foun I in previous
volumes of N.\TtJRE. The seriousness of vibration in steam
vessels is largely dependent upon the period of the hull as a
structure synchronising with the beats of the , engines,
and thus it is that a vessel may vibrate excessively
at speeds less than the highest speed she can attain.
That is the elementary fact upon which a study of
the problem is based. Herr Schlick, in his previous
papers, has already considere i the case of vibrations of the first
order — that is to say, such oscillations of the longitudinal axis of
a ship in a vertical direction as have two nodular points.
Vibrations of this order claim most attention because they are
most common, and are more violent than those of higher orders.
It is in vessels with engines running at high speeds that vibra-
tions of a higher order are sometimes observed. It would, as
the author of the paper points out, be very advantageous if the
naval architect could ascertain beforehand the position of the
nodular points of a ship in getting out the design ; but this, he
is of opinion, cannot be done directly in a satisfactory manner.
Mr. Mallock also enters into this question, as will be seen when
we deal with h s paper later on. As the question cannot be
treated direcily in a satisfactory manner in the case of a ship,
Herr Schlick has recourse to the mathematical investigations
of the vibrations of an elastic, prismatical rod. Such investi-
gations have been made by sever il authorities, and the author
quotes at some length the formula; that have been constructed
for vibrations of the first and higher orders. These it is not
necessary to repeat.

It is evident that in a complex structure like the hull of a
vessel, the vibrations will be of a very different nature to those
of a prismatical rod. Treating only of vibrations of the first
order — for the author has not yet succeeded in correctly ascer-
taining coefficients for the second order — Herr Schlick finds
that in a ship they are at a greater distance from the ends than in a
vibrating prismatic rod ; a circumstance which is explained by the
fact that a ship is less weighted in the ends than in the middle.
For ships of very fine lines, the only class investigated, for
vibrations of the first order the distance of the after nodular
point from the after perpendicular is 0231 to 0253 times the
length of the ship. The distance of the fore modular point
from the fore perpendicular varies from o'jio to 0365 times
the length. Tlie author had already shown that an ordi-
nary engine with three cylinders cannot produce vibrations of
the first order when the moving weights (pistons, &c. ) of each
cylinder are in such proportions to each other that the products
obtained by multiplying these weights by the distance between
the axis of the cylinder and the next nodular point are the
same lor all three cylinders. The same engine, therefore, will
produce vibrations of the second order when the number
of the revolutions increases accordingly. The new nodular
point, moving away from the engine, causes the moments
of the moving weights to be no longer equal to each other.
The author considers, therefore, that as the nodular points can
only be determined after the ship is completed, it is necessary
to alter the moving weights of the engines in such a manner
that their moments respecting the nodular point are made equal
to each other. The vibrations will thus be considerably reduced,
if not entirely avoided. The influence of the screw in pro-
ducing vibration, o*ing to the impulses it imparts at the
exticme end, is also discussed in this part of the pnper ; and
the author then proceeds to deal with the so-called " horizontal
vibrations," which he considers really consist of a twisting action
on the ship's axis, due to the turning. moment of the engines,
acting on a screw, in the case of a single propeller, .^n

570

NA TURE

[April i i, 1895

apparatus, construcied for the purpose, illustrated this fact by
showiti" that the horizontal oscillations at the deck and bottom
of the ship respectively are in opposite directions at the sanne
instant of time. At a certain height above the keel there is no
horizontal oscillation, this being therefore the locus of the axis
of torsion. Maxima and minima of the turning moment at each re-
volution depend on the number of cranks, the amplitude of the
oscillations beinj; mostly dependent on steam distribution. These
oscillations are periodic, and likewise have their nodular points.
The author next proceeds to treat the points mentioned
mathematically in the case of a prismatic rod. He shows that
the number of vibrations is proportional to the speed of pro-
gress of vibration. Substituting a ship's body, he finds that
this speed of progress remains constant for similar ships, and
also that the number of torsional vibrations varies in an indirect
proportion with the length of the ship. For a better under-
standing of these points, we must refer our readers to the original
paper and the diagrams by which it is illustrated. That engines
of special construction will cause no vibration if placed just
above the nodular point, is also true for torsional vibrations.

Mr. Mallock, who, it may be slated, has done much excel-
lent work for the Admiralty in connection with this subject,
dealt in his paper with " the determination of the direction and
magnitude of the forces and couples which arise from the un-
balanced moving parts of marine engines." Something may be
done, the author said, towards balancing an engine by the
proper disposition of the pistons, connecting-rods, and cranks ;
but it does not seem practicable to produce a com-
plete balance in any ordinary engine without having recourse
to counterbalance weights. In order to determine the weights
required, the author has produced a geometrical construction
showing, by the aid of arithmetic only, the resultant force and
couple due to the unbalanced moving parts of any engine. With-
out the aid of the diagrams >hown at the meeting, it would be
impossible to make the explanation clear, even if space permitted
us to give the details in full. It will be sufficient to say that the
engine is divided up into its component parts, to each of which
a value is given, and in this way the resultant force is found and
the resultant couple determined. Having got all the information
necessary to assign the magnitude and direction of the force and
couple which will completely balance the engine, if the force
could be applied at the centre of gravity of the moving parts, it
would merely remain to decide what weights should be used to
produce the required effect. In general the construction of the
engine makes this inconvenient, if not impossible, and other
positions for the counterbalance wtights must be found. This
aspect of the problem is then considered in detail by aid of the
figures.

The second part of the paper was devoted to showing how
the frequency of vibration of any ship, loaded in any manner,
can be found by models, and that all the data for shaping the.'-e
models can be readily obtained from curves which would be in
the hands of the ship designer. .Vn example of the apparatus
used was shown, the author giving a practical illustration of its
working. The course pursued is to make an exaci copy of the
ship on a very small scale, exactly proportional in all dimen-
sions and identical in material. It is known by theory that ih-i
frequency of vibration of the model and ship will be inversely
proportional to their lengths. The model is replaced by an
exact copy on the same scale, made of some other material —
wood— the frequency of the new model differing from that of
the former in the ratio

7'

where y„>, </,, and p, are the respective elasticities (Young's
Modulus) and densities of the wood and the material of the
ship. Next the wooden model is replaced by a jilank of the
same wood of uniform tbicknc-^s but variable breadth, the
breadth being such that the stiffncs of the plank against
bending at every cross section is proportional to the .siilTness of
the model at the coiresponding position. Wtights are fixed to
the plank in such a manner that the weight at any cross section
ia proportional to the weight at the corresponding section of
the model. Then the frequency of the plank, compared with
that of the model, can be ascertained by a formula.

In the apparatus shown the plank was supj)urted by two
rollers tlung from two similar rollers, the lalicr resting on an
overhead railway. The plank was kept vibrating by a magnetic
apparatus, and a recording device was added. The rollers

NO. I32S, VOL. 51]

supporting the plank gave the position of nodes. It is only
when the rollers are at the positions where the nodes would be,
if the plank was free from all constraint, that the frequency of
the plank will be related to that of the ship as given by the
author's formula. The natural nodes are found by varying the
position of the rollers until the frequency is a maximum for the
type of vibrations under consideration.

The method here introduced by Mr. Mallock is interesting
and ingenious, but how far it is applicable to the needs of the naval
architect, or whether the average ship builder, if he wish to
reduce vibration, will prefer the former method of adjusting the
engine to the known conditions of the ship after she is built,
are questions which experience alone can decide.

The paper of Mr. Robinson and Captain Sankey dealt
largely with the question of vibration in connection with electric
light engines, the problem of vibration in the hull of a vessel
bring thus eliminated. Here again a number of diagrams were
used which we cannot now reproduce, and our abstract of this
paper must be therefore brief. Investigation showed that in the
case of an electric light station the high speed vertical
engines, each 200 indicated horse-power, with two cranks
set opposite each other, and run at 350 revolutions per minute,
were mounted on a large slab of concrete. The en-
gines being vertical, the moving parts had to travel through
a greater distance during the upper half of the revolution of
the crank pin, than during the lower half. Calculation
showed that each line of parts singly tended to lift the engine
at up-strokeby about 35 tons, audit tended to depress it 2'3 tons.
Therefore twice in a revolution a net lifting power of one ton
acted upon the engine, and changed an equal number of times
into a depressing power of about i '2 tons. The result was a
"pumping action" on the water-soaked soil beneath the con-
crete slab, and in this way vibration was conveyed to surround-
ing buildings. The action, it will be seen, was due to the
angular movement of the connecting rods, a feature which llerr
Schlick said might be neglected ; a point in which the authors,
naturally, and also Mr. .Mallock, l>yno means agreed with him.

An arrangement of two engines with their framings rigidly
connected, and having three cylinders each, was proposed, the
object being to neutralise the endways rocking or tilting ten-
dency, and also to give freedom from tendency to vary the
downward pressure.

.\ discussion followed the reading of these papers.

Mr. Hiik's paper described a new way ol carrying out 1
known investigation. Whether the new way is better than the
old way, is a point which may be decided by experience. The
last paper of the meeting, that by .Mr. Martin, was of a dis-
appointing nature. Marine engineers have long been asking
for an explanation of the hitherto unexplained fact — if fact it
be — that " induced draught " is so much better for_ boilers than
"forced draught." Mr. Martin's experiments were quite
beside the mark.

The summer meeting of the Institution will be held in Paris,
commencing on June 1 1.

QUESTIONS BEARING ON SPECIFIC
STABILITY}

AT the suggestion of your President, I beg to submit three
questions to the notice of this Society. They bear on a
theoretical problem of much importance, namely, the part played
in evolution by "organic stability."

The questions arc especially addressed to those who have had
experience in breeding, but by no means to breeders only ; nor
are they addre>scd only 10 entomologisis, being equally ap-
propriate to the followers of every other branch of natural his-
lory. I should he gratefid for replies relating to any species of
animal or plant, whether based on personal observation nr re-
ferring to such observations of others as are still scattered
through the wide range of periodical literature, not having yet
found a place in standard works. The questions arc for in-
formation on : —

(l) Instances of such strongly marked peculiarities, whether
in form, in colour, or in habii, as have occasionally appeared in
a single or in a few individuals .Tmorg a brood ; but no record
is wanted of monstrosities, or of such other characleristicj •» ■
arc clearly inconsistent with health and vigour.

' A paper read :ii ihe Eniomological Society, April 3, 189S, by l"r«nci»
Cilton, K.R.S.

April i i. 1895^

NA TURE

571

(2) Instances in which any one of the above peculiarities has
appeared in the broods of diflereni parents. In replying lo this
question, it wil! be hardly worth while lo record the sudden
appearance of eiiher albinism or melanism, as both are well
known to be of frequent occurrence.

Note. — The question is not asked now, whether such pecu-
liarities, or "sports, " may be accounted for by atavism or other
hypothetical cause.

(3) Instances in which any of these peculiarly characterised
individuals have transmitted their peculiarities, hereditarily, to
one or more generations. Kspecial mention should be made,
whether the peculiarity was in any case transmitted in all its
original intensity, and numerical data would be particularly ac-
ceptable, that showed the frequency of its transmission (a) in an
undiluted form, {h) in one that was more or less diluted, and \c)

i of its non-transmission in any perceptible degree.'

It is impossible to exp'ain to a general nieeling the precise
way in which the desired facts would be utilised. An explana-
tion that would be sufficiently brief fur the purpose could not
be rendered intelligible except to those lew who are already
familiar with the evidence, and the technical treatment of it by
which the law of Regression is established, and with the con-
sequences and requirements of that law. Regressiveness and
stability are contrasted conditions, and neither of them can be
fully understood apart from the other.

I may as well take this 0|)portunity of appending a list of my
various memoirs on these sul>jects. They appeared from time
to time in various forms as the inquiry progressed and as
suitable openings occurred for writing or speaking. TI.e more
important of these are Nos. I, 3, part of 6, 7, and S in the
following list. Nos. i to 5 refer to regression only.

List of Memoirs, by Mr. F. Galton, o.n Regression
AND Organic Staihlity.

(1) Typical Laws of Heredity. Journal ol the Royal In-
stitution, 1S77. (This was the first statement of the law of
Regression, as founded on a series of experiments with sweet
peas.)

(2) Presidential Address, Anthropological Section of the
British Association, 18S5. (Here the law of Regression was
confirmed by anthropological observations.)

(3) Regression towards Mediocrity in Family Stature.
Journal of the Anthropological Insttiute, 1885. (A revised
and illustrated reprint of No. 2.)

(4) Family Likeness in Stature. Proc. Roy. Soc, 1886.

(5) Family Likeness in Eye Colour. Proc. Roy. Soc, 1886.

(6) Natural Inheritance. (Macmillan and Co., 1889.) (This
volume summarises the results of previous work.)

(7) Patterns in Thumb and Finger Marks . . . and the
Resemblance of their Classes to Ordinary Genera. Phi!.
Trans. Roy. Soc, 1891.

(8) Discontinuity in Evolution. Mind, 1894. (An article
on Mr. Bateson's work.)

A NEW DETERMINATION OF THE OHM.
A yRE.SII determination of the value of the ohm in
■'^ absolute measure has been made by F. Himstedt
(H'iedemaiin's .4nnalen, liv. p. 305). The method employed
is that which the author had used in a previous deter-
mination, and consists of passing through a galvanometer
all the make or break currents induced in a secondary
coil when the current in a long primary helix is interrupted
a known number of times per second. A known fraction
of the primary current is then passed through the same gal-
vanometer. The primary helix in these experiments consists
of a single layer ol uncovered copper wire, wound, by means
of a screw-cutting lathe, in a regular spiral on a glass cylinder.
The turns of wire are held in their place, and the insulation
improved, by being coated with shellac. As the mean of a
number of determinations, the author obtains the value lo6'28
cm. as the length of the column of mercury at o' C, having a
cross secli')n of one square millimetre, which has the resistance
of lo^'C.G.S. units. In connection with the above-described
experiments, the author has been led to measure some coeffi-
cients of self-induction, using for this purpose a modification
of the Rayleigh-Maxwell method. The great difficulty in
measuring a coefficient of self-induction by -this method is

1 Written coinnniiiications should be addressed to F. Galton, .;2, Kutl.ind
Gate, London, S.W.

NO. I -528, VOL 51]

that, in order to get a throw of sufficient magnitude to be ac-
curately measured, it is necessary lo employ a somewhat strong
current. The result is that the temperature of the coil, the self-
induction of which is being measured, rises rapidly, and thus
the balance of the Wheatstone's bridge for steady currents is
upset. Herr Himstedt (;ets over this difficulty by using the
commutator, which he employs in his determination of the
ohm, to break the battery circuit a known number of times per
second, and to cut the galvanometer out of circuit while either
the mike or break is taking place. In this way a steady
deflection is obtained of sufficient magnitude to be readily
measured, even when the current employed is between 0001
and O-0O2 amperes. The above method only difTcrs from that
employed by Profs. Ayrton and Perry in their secohm-meter, in
that the author takes two separate readings, one with the bridge
balanced for steady currents, the other when the commutator is
working, instead of bringing the galvanometer deflector to zero
by upsetting the steady current balance.

THE SMITHSONIAN INSTITUTION REPORT

FOR 1894.
\ TR. S. P. LANGLEY'S report of the operations of the
■^ Smithsonian Institution for the year ending June 30,

1894, has just reached this country, and it furnishes interesting
reading on a number of points relating to the U.S. National
Museum, the Bureau of Ethnology, the Bureau of International
Exchanges, the National Zoological Park, and the Astrophysical
Observatory.

The total permanent funds of the Institution are now 911,000
dollars, and interest at the rate of 5 per cent, per annum is
allowed upon this by the Treasury, the interest alone being
used in carrying out the aims of the Institution. The total
receipts during the fiscal year covered by the Report amounted to
69,967 dollars, and the entire expenditure, including a sum of
eight thousand dollars added to the permanent fund, was 67,461
dollars. The Institution also disbursed the Treasury grants of
14,500 dollars for International Exchanges ; 40,000 dollars for
North American E'.hnology ; 154,000 dollars for the U.S.
National Museum ; 50,000 dollars for the National Zoological
Park ; and 9000 dollars for the Astro- Physical Observatory.

It appears to be an essential portion of the original scheme
of the government of the Ins' itution that its secretary should be
expected to advance knowledge, whether in letters or in science,
by personal research ; but the increasing demands of time for
labours of administration has greatly limited the possibility of
doing this. Mr. Langley has, however, found time to continue
his researches upon the solar spectrum (see Nature, Novem-
ber I, 1S94). This work, carried on in the Astro- Physical
Ofiservatory, is certainly of more than common importance.
His investigations upon aerodynamics have also been con-
tinued intermittently. They are not complete, but they appear
to poini to conclusions ol general and unusual interest.

A widespread interest seems to have been awakened in the
Hodgkins competition, with reference to investigations appertain-
ing to the nature and properties of atmospheric air. .\ letter
printed in Nature of June 21, 1894, announced that the lime
within which papers might be submitted was extended to the
end of last year. The Report informs us that, up lo June 30,
1894. 250 memoirs, printed and manuscript, had been received .
in connection with the competition, representing correspondents
in the United States, Mexico, England, Scotland, Norway,
Denmark, Russia (including Finland), France, Belgium,
Germany, Austria-Hungary, Servia, Italy, and British India.

A few grants have been made from the Hodgkins Fund, in
aid of certain important researches. In this connection we
notice that Prof. E. W. Morley's work on the determinations
of the density of oxygen and hydrogen, aided by special ap-
paratus provided by the Institution, is approaching completion.

The investigations undertaken by Dr. J. S. Billings and Dr.
S. Weir Mitchell into the nature of the peculiar substances of
organic origin contained in the air expired by human beings,
has been continued under a grant from the Hodgkins Fund, and
also the researches by Dr. O. Luinmerand Dr. E. Pringsheim,
of Beilin University, on the determination of an exact measure
of the cooling of gases while expanding, with a view to revising
the value of that most important constant which is technically
termed the "gamma" function.

Mr. Langley refers again to the unsatisfactory condition of
the National Museum. The collections have increased so

572

NATURE

[April i i, 1895

greatly that unless additional space i« provided for their proper
adroiniftraiion and exhibition, the eflTiciency of the Museum will
be grfatly impairfd ; but though the collections are growing
rapidly in certain directions, they are not increasing as sym-
melrically and consistently as is manifestly desirable — a very
common cause of complainL A defect which calls for instant
atteniinn, however, relates to the most undesirable and
dangerous siorage of c >lleclions in woodi n s'ied< near the
Smiths' n'an building, and in the basement ol ihe building itself,
where large alcoholic collections in bottles containing, in the
bulk, many thousands of gallons of alcohol, have been put away,
as space cannot be found for the specimens in the Museum.
It appears that a fire communicated to these rooms would
sweep ihrtngh the en'.ire length of the building, and although
the building itself is fireproof as against any ordinary danger,
it may well be doubted whe'her any of the colleclims therein
exhibited can be regarded as safe, if the rooms immediately
below should be exposed to so peculiarly severe a conflagration
as would be caused by the ignition of these large quantities of
inflammable material. Such a calamity would affect the whole
scientific world, and we trust that the appeal for a change of
the present condition of aflTairs will not be disregarded.

The investigations relating to the ethnology of the Ameri-
can Indians were carried forward during the year, under
the efficient control of Major J. W. Powell, the director,
aided by Mr. W. J. McGee, ethnologist in charge, asexrcutive
officers. These researches of the Bureau of American Ethno-
logy embrace the subjects of archaeology, descriptive eihnology,
sociology, pictographyand sign language, Unguis ics, mythology,
psycholog), and bibliography, and the results obtained during
the year have never been exceeded in value.

The Smithsonian Exchange Service was inaugurated nearly
half a century ago, with the object of carrying out one of the
purposes of the founder of the Institution in the diffusion of
that knowledge which the Institution itself helped to create.
For this purpose it established correspondence with scientific
men all over the woild, until there is no civilised country or
people, however remote, upon the surface of our planet, so far
as is known, where the Institution is not thus represented.
These corre pondents have grown in numbers until at the pre-
sent lime those external to the United States alone number
nearly ly.oco. More than one hundred tons of books passed
through the exchange office during the fiscal year 1893-94,

It was only five years ago since an appropriation was made
for the National Zoological Park at Washington. The park
has an area of nearly 167 acres, but there are as yet only four
permanent buildings, while the animals number 510, of which
200 are of the larger size. Comparing this with .similar establish-
ments at other capitals, it is noted that the Gardens of our
Zoological Society cover about 36 acres, are crowded with
buildings, and that the magnificent collection of animals, some
2300 in numi cr, is housed in a fairly comfortable manner. In
Pans the portion of the Jardin des Plantes assigned to animals
is a plat of ground some 17 acres in extent, crowded with 900
animals. In IJerlin the portion of the Thiergarten appropriated
for animals occupies about 60 acres. Fifteen hundred animals are
accommodated and, necessarily, much overcrowded. In the
United Slates the principal collections are in Philadelphia, wheic
the grounds occupy about 40 acres, and the collection comprises
•881 animals; in Cincinnati, where 36 acres are occupied with
about 800 animals ; and in New York, where the city maintains
about 700 animals in Central Park, occupying an area of ap-
proximately 10 acres. In none of these collections are the
grounds of sufficient size 10 give any extensive range for the
aoiutals.

Appended to Mr. Langley's general account of the affairs of
the Institution and of its bureaus, are the detailed and statistical
reports from the officers in charge of the different branches of
woik. The whole shows how very great and valuable is the
work done in the United States " lor the increase and diffusion
r>f knoA ledge among men."

UNIVERSITY AND EDUCATIONAL
INTELLIGENCE.

P«op. C. S. SitEKKiNGTON, F.R.S , has been appointed to
the George Holt Chair of Physiology in University College,
l-ivcrpool.

NO. 1328, VOL. 51]

Pr. a. W. Crossi EY, Berkeley Fellow, and Demonstrator
of Organic Chemistry, in theO«ens College, Manchester, has
been elected Demonstrator of Chemistry in the Medical SchooV
of St. Thomas's Ho.^pital, in succe-sion to Dr. \V. H. Ince,
who has been appointed Government Chemist at Trinidad.

Sir Dinshaw Manockjiu-: Petit, Bart., h.is, through
the Principal, Mr. S. Cooke, offered to the Indian Government
the sum of 50CO rupees towards the cost of provi ling residential
quarters for Parsee students attending the College of Science at
Poona.

The Governors of Colfe's Found.\lion have selected Mr.
F. W. Lucas to be Head .Master of Colfe's Grammar School,
Lewishim, from September next. Mr. Licas is at present
Head Master of Hipperholme Grammar School, Yorks, and
was formerly Senior Assistant and Science Master at Roan
School, Greenwich.

We learn from the Lancct,\\}!\3X in accordance with the
will of the late Dr. G. Y. Heath, Professor ol Surgery in the
University of Durham, and President of the University of
Durham College of Medicine, the trustees of the Heath
Scholarship, Prof. \V. C. Arnison and Mr. Frederick P-ige,
will award and pay to the writer of the best essay on Surgical
Diseases of the Jaws the sum of £200. All graduates in
medicine or in surgery of the University of Durham are
eligible to compete lor this prize. The essay must be type-
written or printed, and delivered to the trustees not later
than March 31, 1S96. The essay, together with any
specimens, drawings, casts, microscopical preparations, or
other means of illustration accompanying it, will become the
property of the College of Medicine, Newcastle-upon Tync,
but by permission the essay may be piinted for general circu-
lation by Ihe Heath Sch'vlar. Mr. Stephen Scott, of Hairogale,
has generously prestnted to the College of Medicine the sum of
/■looo, which has been devoted, in accordance with Mr. Scott's
wish, to founding a scholarship to promote the study of hernia
and allied subjects. .\ny graduate in medicine or surgery of
the University of Durham, or any student of the University of
Durham College of Medicine is eligible to compete lor the
scholarship, provided that such student shall have had at least
one academical year in attendance at the College, and that in
any case his age does not exceed thirty years at the time when
the essay is sent in. The competition takes place every year-
Essays for this year's competition must be sent not later thaa
July 31, 1S95, '° Prof. Arnison, University of Durham College
of Medicine, Newcastle-upon-Tyne.

On Friday last, Mr. Acland received a deputation at Ihe
Education Office, from the representatives of the Association
of Head Masters, respecting the recent regulations which have
been issued by the Science and Art Department with icference
to organised science schools. After hearing the views of the
deputation, Mr. Acland, in reply, said it was not desired to
make an upheaval of the arrangements for these schools, but
to j >in together in improving the method and ihc system on
which the leaching was carried on. They were all agreed that
to lessen too frequent examination, and to introduce the element
of inspection, il reasonably carried on in a friendly spirit,
would be of great value to these schools. One of ihe object*
of the Department had been to make it clear that, besides the
teaching of science, which was the primary object of these
schools, they also desired fully to recognise the element of
literature and the leaching ol special sutijecls. In order Vy '
meet a point which had been raised, as to the change from
the old system of organised science schools to the new, the
closing words of the syllabus would be: — " ReasonaWe lati-
tude will be allowed for two yeais in any departures which may
be made frcm ilie prescribed course while the changes from the
present to the new sy.stem are being brought about." Taking
these word>, together with the words in the earlier part ol the '
s)llabus, as to leasonnble latitude being allowed to teachers as |
to the nattre of Ihc course which they might pursue, provided
that the instiuclion was sound, satisfactory in amount, »nd i
combined with proper jiiactical work, it would be seen that .
the Depaitnent had no ihleiition of being too despotic, and '
that if really good and reasonable work was done under some
more clastic !.)stem, the.se organised science schools would be
found of even more benefit in the luluie than they had been W I
the past. I

Apj<il 1 1,

'»95]

NATURE

573

SCIENTIFIC SERIALS.

The Mathimalual Gazette, No. 4 (Macmillan).— This is the
firsl number of the- enlartjed series. We are glad to find that
the suiiport accorded i') che first year's issue has been sufficient
to warrant this enl.Trgement ; hut to make the Gazette a success,
and not a drag upon the fund-; of the Association, it is impera-
tively necessary that a much larger measure of support should
be rendered by the general body of ma hematical teachers
The opening paper is one on al^e'ira in schools, which was read
before the Associition at its annuil meeiing in January of this
year. In this article the author, Mr. Heppel, drawing upon his
wide experience as a ' coach," sla'es that when tmpih have come
to him he has found that the work in algebra has usually to be
done all over again. The reason of this appears to him to be
" the ever-growiiiiT divergence there is between the conception
of the nature and objects of algebra that dominates school
teaching and the conception that regulates the application of
algebra to more advanced maihematici." Many of the sugges-
tions are likely to be useful, and we commend them to the
notice of our brethren in the craft of teaching. —Mr. T. Wilson
contributes a note on mathematics for astronomy and navigation,
in which he suggests that the elements of spherical trigonometry
might occupy a more prominent pUace in school teaching than
they do, and to cover all ages he winds up with, *'let no one
<lespair that he is tooold for mathematics." — Mr. Rouse adds a
secoi'd chapter to his previous interesting article on conies. —
"SomedM text-books" is a review of John
Ward's "The Young Mathematician's
Guide" (1747), by Mr. J. H. Hooker,
which brings before us matter that was
served up for the food of students in the
time of "good Queen Anne." The rest
of the number is taken up with more ex-
tended ariicles (than bcfoe) entitled notes,
solutions, new (^urstions, and litles of new
books. These latter pag s should be of
general interest, a.; they are likely to be
useful both to students and teachers.

Bulletin of the American Mathematieal
Soci/ly, ■O'ics 20, vol. i. No, 6, March
1895. — The notice of "Arthur Cayley,"
pp. 133-I41, whiih opens ih s nimber, is
a warm appreciaii m ol the clia acier and
writings of our great m.ithcmatician, by
Dr. Charlotte Scott, and is due to her
"intense ad i.iratioit for his work and
personality, and to the fact that for the
last fourteen years" she has ** been
privileged to know him and experience

his kindness," It is the fullest account we have yet read, and
h-is manv m ire points of imcrest for an Englishman than Sijjnor
Brioschr's ilo^e, which i- naturally cont'rned more closely to an
apprtciaion of los mathemancal work. One extract we must
make : — " Any sketch of Prof. Ca> Icy is self-condemned if it
leaves out ol account the child like purity and simplicity of his
nature, the entire freed'^m from the professional touchiness on
the score of priority to which mithematiciani arc as liable
as other men. He was ever ready to ray what he was
working at, to in licate the lines of thought, to state
what difficulties he i»as encountering . . . fiut his great-
ne s and his simplicity cinnot be enshrined in anecdotes.
— Prof. Osgood (pp. 142-154) m " Tne Theory of Functions,"
analyses, chap'er Ity chapter. Or. (now Prof.) Forsyth's brilliant
work on "Tne Theory of Functions of a Complex Varialde,"
and winds up thus : — " The tiook is not one thn can sa'elv be
put into the hands of the immature student for a first iniiodu;-
tion to the study of the theory of lunciions. But the student
who is already famili ir wi h the elements, and who has acquired
some degree of CI i ical power, will find its pages incentive to
valuable work in this wide fie d." — A sh Tt no e fnlUiws on the
inlroductii n of the notion of hyperbolic functions, by Prof.
Haskell, wfiiih wrs rearl bef»re the Society at its Dtceiiiber
(■894) imeing. — The second summer meeting of the Society is
to be held at Springfield, Mass , on August 27.

Inlet nationalfS Arthivfiir Ethno^raphie. Ifand vii. Heft iv.
1894. This pan cimiiuencc^ wiih a long an! thorrmgh study
(in Oermnn) on t' e hair-cutiii g cu-loms of 'he Southern Slavs,
fcy Fricdiich S. Kr.iuss. Several songs are reproduced in the

NO. i3-;8, VOL. 51]

original, which are also translated info German. In this study
two elementary ideas of mankind are met with, but imbued
with the local colour of the Southern Slavs, and varied in tint
according to the stage of culture. Hair cutting is a means of
adoption into kin-hip, and also as a redemption from ihe sacrifice
of the liody or life to the spirit of disease. It is a rite per-
firined for social obligations and for good luck. — Prof. P. J.
Veth concludes his exhaus'ive account (in Dutch) of the Man-
drake, which is a valuable contribution to signature-lore or
sympathetic magic. The most interesting of the " Notes" is
an illuslraled communication by A. Herrmann, on the cupping
and blood-letting appliances of the wandering gypsies.

SOCIETIES AND ACADEMIES.

London.

Royal Society, March 21.^" On the Diselectrification of
Air." By Lord Kelvin, P.R. S., Magnus Maclean, and
Alexander Gait.

§ I. The experiment describerl in § 14 of our paper on the
" Electrification of Air and other Gases by bubbling through
Water and other Liquids" (Roy. Soe. Proc, February 21,
1895), proves that air, electrified negatively by bubbling
through water and caused to pass through a metallic wire gauze
strainer, gives up some, but not a large proportion, of its

J/i Melrc.-i

Fig.

electricity to the metal. We have now made a fresh experi-
mental arrangement for the purp ise of investigating di. electri-
fication of air which has been electrified, whethT p tsiiively or
negatively, by other means than bub'iling through water ; with
apparatus represented in Figs, i and 2, which is simplified from
that of our former paper by the omission of the apparatus for
electrification by bubbling, and for collecting large quantities of
electrified air.

§ 2. In Fig. I, A B represent the two terminals of a Voss
electric machine connected, one of them to a metal can, c c' (a
small biscuit canister of tinned iron), and the other to a fine
needle, of which the point « is in the centre of the can. The
wire making the connection to the needle parses through the
centre of a hole in the side of the can, stopped by a paraffin
plug. Air is blown from bellows through a pipe, E, near the bot-
tom of the can, and allowed loescipe from near the top through
an elec ric filter, F, called the tested filter, from which it passes
'.hrimgh a long block-tin pipe, c G, about 3* me'res long and
I cm. internal diameter, and thence through a short tunnel in
a block of paraffin, K. From this, lastly, it passes through a
seconil electric filter, R, into the open air. This second filter,
which we sometimes call the testing filter, sometimes \heeleetric
receiver, is kept in metallic connection with the insulated
terminal, I, of a quadrant electrometer, 0. The metal can and
the block tin pipe are metallically connected to the outer case
and uninsulated terminal, T, of the quadrant electrometer.

§ 3. The testing filter or electric receiver consi^ls of twelve
di-cs of brass-wire cloth fixed across the mouih of a sho't metal
pipe supported on the end of the paraffin tunnel in the manner

574

NA TURE

[April 1 1, 1895

represented in Fig. 2, on a scale of twice the size of the filter
which we have actually used, or of true size for a filter on a
tube of 2 cm. diameter, which for some purposes may be
belter. One of eleven similar discs, of size adapted to a
tube of 2 cm. diameter, and an outermost disc with projecting
lugs, are shown, true size, and with the gauge of the wire-cloth
which we have actually used, shown true size, in Fig. 3. The
eleven little circular discs of wire cloth are held in position by
bending over them the four lugs belonging to the outermost
disc, and all are kept compactly together by a short piece of

Fio. 2,

india-rubber tube stretched over them outside, as shown in
Fig. 2.

§4. We commenced with a few experiments to test the effi-
ciency of the testing filler, R, with no tested filter at F, and
merely continuous block-tin pipe, FCG, from the can to the
paraffin tunnel. First, working the bellows with no electrifi-
cation of the needle point, wc found no sensible electric effect
on the electrometer, which proved that, whether from natural
electrification of the air of the laboratory, or by the action of
the bellows, or by the passage of the air through the long metal
pipe, no electrification sensible to our test was produced. After

I

Fig. 3. — Twenty-five wires 10 the rentimetre. Diameter of each wire is
"*i6 mm. Hence each aperture is 0*24 mm. square.

thai we kept the needle point, «, electrified, either positively or

vcly, (or five or six minutes at a time by turning the little

machine, and we found large effects rising to about 3J

v.ilu in five minutes, positive or negative, according as n was

positive or negative.

§ 5. The apparatus is now ready to test the efficacy of filters
or other appliances of different kinds placed at I fur the pur-
pose of diseleclrifying air which has been electrified, whether
positively or negatively, by the electrified needle point n. We

NO. 1328, VOL. 51]

began with a filter of 12 wire-gauze discs, placed at F and kept
in metallic connection with the tin pipe outside. This nearly
halved the electricity shown by the electrometer. We then
tried 24, 4S, 72, 96, 120 wire-gauze discs, successively, placed
in groups of 24, and separated from one another by short
lengths of 2 cm. of lead tube, in the line of the flow of the air
between F and G (Fig. i), all kept in met.illic connection with
the block-tin pipe and the outer case of the electrometer. We
were surprised with the smallness of the additions to the dis-
eleclrifying efficiency of the 12 strainers first tried : for ex-
ample, the filtrr of 120 wire g.iuzes only reduced the electrical
indication to a little less than one-half of what it was with ttie
12 which we first tried.

We found that cotton-wool between the spaces in the groups
of 24 wire gauze's largely increased the diselectrifying effect.
Thus, with 72 wire gauzes and cotton-wool we succeeded in
reducing the electrical effect to ahout one-twelfth of what it
was with only a filler of 12 wire gauzes ; but hitherto we have
not succeeded in rendering imperceptibly small the electricity
yielded liy the outflowing air to the testing filler R in our
method of ob-ervation.

§ 6. We intend trying various methods of obtaining more
and more nearly complete diselectrificatlon of the electrified air
flowing out of the can at F ; and this for air electrified other-
wise than by the needle point, as shown in the diagram : for
instance, by an electrified flame in place of the needle point ;
or again by bubbling through water or other liquids. Mean-
time, the mere fact that the electricity, whether positive or
negative, given to air by an electrified needle point, can be
conveyed through 3 or 4 metres of small metal tube (I cm.
diameter), and shown on a quadrant electrometer by a receiving
filter, is not without interest. We may add now that, with the
receiving filter removed and merely a fine platinum wire put in
the mouth of the paraffin tunnel, we have found that enough of
electricity is taken from the outflowing air to be amply shown
by the quadrant electrometer ; which renders even more sur-
prising the fact that the diselectrifying power of 120 strainers
of fine wire-gauze should be so small as we have found it.

"On the Question of Dielectric Hysteresis." By Alfred W.
Porter and David K. Morris.

The experiment described was intended to test whether the
dissipation of energy that occurs in the dielectric of a condenser
is due to true hysteresis (as claimed by Riccardo Arno), or simply
to viscosity. To discrimina'e between them it is essential that
the condenser be put through a cyclic series of states at such a
slow rate that all viscous effects shall have had time to subside
before a measurement of the charge corresponding lo a certain
potential difference is made. It is essential also to arrange

PotcntiaL differenct.

Fic. I.

that any lest of the charge which involves a change of stale
should ilsclf form part of the cycle. This was accomplis.ied
by making the cycles as shown in the figure, the cyclic order
being RrURPSQltR; the portions PU and QU repre-
senting discharges through a galvanometer. If hysl'-resi-^
exist, the change of charge QT will be greater than the change
I'T. As the result of twelve cycles the ratio qt/pf comes

I I

out I -r azrr ; a second series of twelve gives I — 73773-

Hence the cha'gc is scnsilily the same for a given value of
the potential difference, whether that value has been arrived
at from lower or from higher values than itself.

April ii, 1895]

NA TURE

575

Fresh evidence is also given of the presence of viscosity.
Thus while the condenser here experimented upon exhibits
marked viscous effects, yet the authors could detect no hysteresis.

Entomological Society, April 3. — Prof. R. Meldola,
F.R.S., President, in ihe chair. — Mr. C. J. Gahan exhibited
two examples, male and female, of a rare Prioned beetle,
Chariea cyanca, .Serville, which had been kindly sent to him
for examination by M. Rene Olierthiir ; and stated that
Lacordaire was mistaken with regard to the sex of the specimen
which he described in the " Genera des Coleoptcres." He
pointed out that the elytra of the male were relatively much
shorter than those of the female; and that the joints of the
antennce from the third to the tenth were biramose. Mr.
Gahan aho exhibited two species of the genus Decarthria,
Hope, and said he believed these were the two smallest species
of Longicorns known. — Dr. Sharp, F. R. S., exhibited the
soldiers and workers of a species of Termites found by Dr.
Haviland in South Africa. He stated that these insects
possessed eyes and worked in daylight like Hymenopterous
ants, and that in habits they resembled harvesting ants by
cutting grass and carrying it into holes in the ground. Dr.
Sharp said that although these holes were probably the
entrance to the nests. Dr. Haviland was unable to find the
actual nest, even by prolonged digging, so that the winged
forms were still unknown. He thought this species was
probably allied to Vermes viamm of Smeathman, in which the
soldiers and workers possessed eyes, and hail been observed by
Smeaihman to issue from holes in the ground, but whose nests
could not be discovered. Mr. McLachlan observed that it was
possible there might be species of Termites without any winged
form whatever. — Mr. r<ye called attention to the action of one
of the Conservators of Wimbledon Common, who, he stated,
had been destroying all the aspens on the Common. He
inquired whether it was possible for the Entomological Society
to protest against the destruction of the trees. Mr. Goss said
he would mention the matter to the Commons' Preservation
Society. — Mr. Francis Gallon, F.R.S., read a paper entitled
"Entomological Queries bearing on the Question of Specific
Stability." (Seep. 570.) — Mr. Merrifield stated that he received
some years ago, from Sheffield, ova of Stienia illuslraria, the
brood from which produced, in addition to typical specimens,
four of a dark bronze colour, and from these he bred ^ number
of specimens of a similar colour. — Dr. F. .\. Dixey referred to
a variety of the larva of Saturtiia carpini with pink tubercles.
He said the imago bred from this larva produced larvae of
which 10 per cent, had pink tubercles. Prof. Poulton, F.R.S.,
said he had lound larvx of Smerinthus ocellalus with red spots,
and that this peculiarity had been perpetuated in their
descendants. Mr. McLachlan, Canon Fowler, and Prof.
Meldola made some further remarks on the subject.- -.Mr.
G. F. Ilampson read a paper by Mr. C. \V. Barker, entitled
" Notes on Seasonal Dimorphism in certain species of Rhopalo-
cera in Naial." Mr. Merrifield said he was of opinion that a
record of the temperature at dilTcrent seasons would be a very
desirable addition to observations of seasonal dimorphism.
Mr. Hampson srid he believed that temperature had very little
to do with the alteration of forms. At any rate, according to
his experience, in India the wet season form succeedeil the dry
season form without any apparent difference in the temperature.
Prof. Poulton remarked that the apparent temperature as felt
must not be relied upon without observations taken by the
thermometer. Dr. Dixey, Mr. Barrett, Dr. Sharp, and Prof.
Meldola continued the discussion.

Zoological Society, .Vpril 2.— W. T. Blanford, F.R.S.,
Vice-President, in the Chair. — Mr. Boulenger exhibited the
type specimens ol two new chameleons from Usambara, German
East Africa. Special interest attached to them from the fact
that they appeared to be more nearly related to the Madagascar
species than to any of the numerous forms now known from
Continental Africa. — Mr. Waller E. Collinge read a paper on
the .sensory canal system of fishes, treating of the morphology
and innervation ol the system in the Physostomous Telcostei. —
Dr. Mivart, F. R. S. , re.ad a paper descriptive of the skeleton in
Lorius llavopalliatus, comparing it with that of Psittacus
erilhaais, and pointed out a number of differences in detail. —
Mr. G. A. Boulenger, F.R.S., made remarks on some cranial
characters of the salmonoid fishes, and expressed the opinion
that there was no justification for separating Coregonus and
Thymallus from the Salmonidx, as had been proposed by Cope

NO. I 328, VOL. 5 1]

and Gill. — Prof. T. W. Bridge read a paper in which he pointed
out certain features in the skull of Osteoolossum. The author
directed attention to the existence of a peculiar oral masticatory
mechanism in Osteoglossiim formosum, distinct fro u that fur-
nished by the upper and lower jaws and their teeth. The
existence of an essentially similar mechanism in the Ganoid
Lepidosteus osseus was also described, and the conclusion sug-
gested that the two genera offer in this respect an interetrting
example of parallelism in evolution.

Linnean Society, March 21. — Mr. C. B. Clarke, President,
in the chair. — Prof. Stewart exhibited an! made remarks upon
a series of corals, divelling upon certain characteristic features
which illustrated their structure. — Mr. S. Pace brought forward
a collection of shells belonging to the genus Columbclla, and
made some observations concerning the peculiarities and the
geographical distribution of some of the species exhibited. .\
paper was then read by the President, "On the terminal flower
in the Cyperace<e." .-Vfter remarking that theorder Cyperaceish?iA
been newly arranged by Dr. Pax in Engler's " Jahrbiicher "
(1886), and in Engler and Prantl's " Pllanzenfamilien," the
character taken for primary division of the order being the
inflorescence, he pointed out that in the first sub. order
Scirpoidea; wih an axillary flower were placed Cyperus,
Scirpua, Psilocarya, Dichromcna, and Hypolytrum ; in the
second sub-order Caricoideae with a terminal flower were placed
Schoenus Rytichospora, Alapania and also Carex, Scleria^ and
their allies. The disrupion of Hypolytrum from Mapania, ol
Dichromeiia and Psilocarya from Kynchospora, he thought,
proved either that the modern method pursued by Dr. Pax was
of limited systematic value, or that he had grievously erred in
his ascertainment of the fact whether in such genus the flower
is terminal or not. Mr. Clarke exhibited his own analyses of
the spikelet in the larger genera in dispute. He held that in
Carcx, Scleria, and their allies, the flower, male and female,
was strictly axillary; that in Rynchospora it was axillary — •
exactly as in Dichroinena and Psilocarya — while in Hypolytrum
the flower is terminal exactly as in Alapania. He further main-
tained that these facts could be sufficiently shown by the aid of
a penknife and pocket-lens, and that no results which might be
hereafter obtained by studies in development could affect either
the weight to be attributed to the character of " terminal
flower," or to the real affinities of the genera. The paper was
illustrated by lantern slides illustrating dissections, and, in the
discussion which followed, criticism was offered by Sir D.
Brandis, Mr. A. B. Renile, Dr. Prain, and Dr. D. H. Scott.
— On the conclusion of this paper. Dr. II. Field, of Brooklyn,
New York, made some remarks on the proposed establishment
of a central inteinational bureau for zoological bioliography,
and the annual publication of an international Zoological
Record.

Mathematical Society, April 4. — Major MacMahon,
R..\., F.R.S., President, in the chair. — The Rev. T. C.
.Simmons read a paper on a new theorem in Probability. The
author replied to numerous questions put to him by Messrs.
G. H. Bryan, Burton, Cunningham, and the President. — The
President (-Mr. Kempe, F.R S., in the chair) communicated a
note on the linear equations that present themselves in the
method of least squares. — The following paper was taken as
read : On the Abelian system of differential equations and their
rational and integral algebraic integrals, with a discussion of
the periodicity of .\belian functions, by the Rev. W. R. W.
Roberts.

Geological Society, March 20.— Dr. Henry Woodward,
F.R.S., President, in the chair. — On fluvio-glacial and inter-
glacial deposits in Switzerland, by Dr. C. S. Du Riche Preller.
This paper is the outcome of one published in the Geological
Magazine of January 1894, on the "Three Glaciations in
Switzerland," in which the author described various glacial
deposits near the lake of Zurich. He now describes a series of
fluvio-glacial conglomerates and in.erglacial lignite-deposits
near the lakes of Ziiricb, Constance, Zug, and Thun, which,
together with analogous deposits at the base of the Eastern,
Western, and Southern Alps, constitute further evidence of two
interglacial periods, and theref )re of three general glaciations,
the oldest of these being of Upper Pliocene, and the others of
Middle and Upper Pleistocene age respectively. As regards
the origin, age, and the time required for the formation of
several of the Swiss deposits referred to in the paper, the author
arrives in several respects at conclusions differing from those

576

NA TURE

[April ii, 1895

recently enunciated by others. The author also argues that the
6rst interglacial period was probably of shorter duration than
the second ; and in confirming his former conclusion that every
general gjaciation marks a period of fiUing-np, and every inter-
glacial period marks a period of erosion of valleys, he avers
that, if this conclusion be correct, it must needs be destructive
of the theory- of glacial erosion.— The Bajocian of the Mid-
Cotteswolds,' by S. S. Buckman. The Mid-Cotteswolds is
defined as the district between the valleys of the Frome and
the ChelL A description of twenty-five sections is given, deal-
ing principally with the strata found between the Upper
7V7»OT;/a-gTit and the Upper Freestone.

Pari<.
Academy of Sciences, Apiil i.— M: Comu in the chair.—
On the composition of drainage waters, by M. P. P. Deherain.
An account is given of experiments made on a large scale with
fall-w-land and with crops of barley, wheat, beel-root, and the
vine. The observations began regularly in March 1892 ; the
results are given for three seasons. Comparing the crops of
1S93 and 1894 as regards nitrogen, it is seen that the abundant
crop of the latter year leaves the soil no more exhausted than
the medium crop of 1S93. The nitrates produced in the soil, or
added as manure, were belter utilised in 1S94 ; with the po >rer
crop a proportion was lost. The author differs from M.
Schlosing, insomuch as the latter believes the loss of nitrogen
in drainage water to be so insignificant as to be able to be
neglected in practical farming, whereas his own results con-
firm the Rothamsted experiments, and show that the lo^s from
fallow-l-inds is much greater than from lands covered with
vegetation. The deduction is drawn that it is good practice to
follow up crops such as wheat by some form of autumn growth.

Ultra-violet radiation of the solar corona during the total

eclipse of April 16, 1893, by M. H. Deslindres. A descrip-
tion of a photograph of the spectrum of the c rona obtained in
the Senegal expedition of 1893. The photo-spectrometer used
had lenses and prisms of quartz and calcite, and thus enabled
a great prolongation of the ultraviolet region to be photo-
giaphed. In accordance with previous observations, it was
(ound that the ultra-violet spectrum was very feeble in intensity
a-i compared with the red : this may be due in part to the great
absorbing power of the atmosphere for light in this region ol the
spectrum. — Solar observations of the second, third, and fourth
quarters of 1894, by M. Tacchini.— On the theory of equations
to the derived partials of the second order, by M. E. Goursal.—
On the sequences of circular permutations, by M. Desire .Vndre.
An analogy is pointed out between circular and rectilinear per-
mutations, and it is shown that the former are, in general, more
simple. They are not subject to the irregularity introduced
into rectilinear permutations by the terminal terms.— On the
application of the theory of probability of errors to levelling
operations of precision, by M. M. d'Ocagne.— On gratings used
in "photogravure," by M. Ch. Fery. A grating of 40 to 60
lines to the centimetre is used to enable the production of a
photograph which can be directly reproduced by mechanical
processes. Such a photograph must necessarily be devoid of
half-tints ; the device of placing a grating at a short distance
before the sensitive surface replaces these half-tints by alternate
black and white squares of the same size. An explanation of
this effect is given by the author on the basis of the elementary
theory of shadows. On the "molecular deviation" or the
"molecular rotatory power" of active sub^tanccs, by M. A.
Aignan. The author asserts that M. Guye's formula for mole-
cular rotatory power is inexact, and cannot be used instead of
Biot's formula for the specific rotatory power in the case of
solutions. — On a radiometer of symmetrical construction, turn-
ing under the action of unsymmetrical illumin.ation, by M. G.
Seguy.— An absolute electrometer for high potentials, standard
and simplified types, by MM. M. Abraham and J. J.cmoine.—
An extremely sensitive galvanometer, by M. Pierre Weiss.— On
the oldest French series of meteorological and thermomctric
observations, by M. I'abbe Maze. An account of the contents
of a newly-discovered register, entitled "Ad thermomelrum
obscrvationes anno 1658 Parisiis : Thermometrum Florcntia;
fabricaium." — On the first mercury thermometer, by M. I'abbe
Maze. Ismacl Boulliau used a mercury thermometer together
with his Florence thermometer in March 1659, or sixty-two
years before Fahrenheit's invention —Thermal study of the
anhydrous barium and strontium iodides, by M. Tassilly.— On

M. de Forcrand. .\ thermal study of the compounds—
(CsHsOWCaO),, (CH40VBaO)3. and (CjHeOjjlBaOV The
action of alcohols on the alkaline-earthy oxides does not give
true metallic alcoholates, but addition compounds.— On the
ammonium b.ises deiived from hexamethyliri-imidotriphenyl-
methane and their action on the fuchsines, by M. A. Rosensiiehl.
—On some new combinations of hexamethylene-amine, by M.
Delepine.— On the gases of the swimming bladder of fishes, by
M. Jules Richard. These consist of oxygen, nitrogen, and
traces of carbon dioxide. The oxygen varies in three cases
given from 786 toSy? per cent.— Action of the nervous system
on the principal lymphatic canals, by MM. L. Ca.uus and E.
Gley.— On the genus Kiitya, of the family Ternstra-miacex-, by
M. J. Vesque.— On the basic rocks occurring as narrow veins m
the Iherzoliie of the Pyrenees, by M. A. Lacioix. There are
two families of granular basic rocks, without peridote and
felspar, which are allied to the peridotites.

BOOKS and SERIALS RECEIVKU.

Books.— R.^infall in ihe F.a^t Indian .^rcViipclago, 1S93 (Balav.a).— Short

udies in Nature Knowledge; W Gee tMac.nillan).-slire'ocheniie : L.

Monod(P.iris. Gauth.er.Villar.).-l>raclicil Microscopy. O.t- Davis,

St-

?rd'cX'iMV^'iienY-1:ambVidg7Naturai"Hisiory--MolluJc^ ^^^^">-

pods : Rev. A H. Cooke. A E. Shipley, and F. R. C. Keed (Macraillan).
-Manual ol Geology : Prof. I. D. liana <th edition (New Wk.A.nerican
Bo.k Company).-The Spirit of Co.kery: Dr. J. L W rhud.chun.
(Baillil-'e) -The Evolmion of Industry : Hy. Dyer (Marmillan) -Horses,
■\sses. Zebras, .Mules and MuleBieeding : W. B. Te«e.meier and C. L.
Sutherland (Co.x). -Sir Samuel Baker-A Memoir: 1. D. Murray and A.
S. While (Macmilla..).-Our Teelh-Care and Preservauon . Dr. V.
Dilcham (B.iillilre).-Clioical Lectures on the Prevention of C .nsumpuon .
Or W Murrell(Baillicre).-l-a Fonclionnemenl dcs Madi.nes a Vapeur .
G Leioutre (P.ir.s. Gaulhier-V.llars) -Des Mare;,: P. H..U (Pans
Gaulhier-V,llars).-Manche,ter Museum : Owens Col efie, t-alalogue of
ihe Library: W. E. Hoyle (Maochesler, C .rnish) -M=tt,odisches Lehr-
buch der Elementar-Ma.bematik : Dr^ G. HoU nil ler. Ers-er und ZweUer
TeiULeipzie, I'eubner).— the B:>ok ofihe Dcad-tac-simileof ihe Papyrus
ofAniinlh?Briti.h Museum. 2nd edition (British Museum).-lne Fam-
ti .n of Africa : J S. Kellie. 2nd edition (Stanford). m„ . ■

Seriaus -Scnbner-s Maga.me, Apnl (, ow).-Mctcor,c P.ipers No^i.
I. Calvert (Lond m).-Namral History of Plants : kern.r and Oliver.
Part 12 (Black.e).-Notes from ihe Leyden Museu.n, Vol. xvi. Nos. 3 and
4(Le,dcn. Brill).-Mind, April (Williams .■indNorBatej.-HroceedmKs of
fhe Societ; for Psychical Research, March (Pa.it)K - Plionosrap iic gu..r eriy
Keview. April (P..man).-Transac.ions of .he Na.ural H'-»7 J»,'i'''>- oj,
Oueensland. Vol. . (Brisbane) -liMllelin of ■{"= Geographical Uub of
Philadelphia, March (Philadelphia).-Records of the t'5,°l°8'"' ^""7.™
India. Vol. xxviii. Part . (Calcut.a).-Bulletin of the New Yo k Mathe-

matickl Society, March (New York M»<:"''ll='")-Mi','''""-"''5f,L:V?Fdin'
February (Macmillan).-Annals of Sc .ttish Natural Hi-t .ry, Apnl (Edin-
burgh, Douglas) -Reliquary and Ill.is.ra.ed Arch.-c .logist, Apn (Bern-
rose) -Archiv fur Patholo^ische An»'r"L ■'"'' ,'^''>^!'' "«T„„Tp J.
Klinische Mcdicin, Band .,0, Uef. i (Uerlm, Kj"".'='>:-«'.'r;""='r" "A^d™'
April (Berlin. PaeteD.-Proceedmgs of ihe Physical Society of London,
Vol. 13 Part s (Taylor and Francis^

PAGE

By Prof J.

CONTENTS

Physiology of the Excitable Tissues

Burdon Sanderson, F.R.S

The Physiology of Plants

Mines and Minerals

Our Book Shelf:— ,,,„.„

Sexton: " Elementary Text-book of Metallurgy
Blake: " Annals of British Geology,_l893 " ....

Mason: " The Origins of Invention " . ......

Gee- "Short Studies in Nature Knowledge . . .
Whiteley : " Org,anic Chemistry : the Fatty Com-
pounds " .

Letters to the Editor:- j t, k „

The Age of the Karih.-Dr Bernard Hobson .

Prof. W.J. SolUs, F.R.S

Polycmbryony.— Frank J. Cole

Improvements in Photometry bV>

Notes 56'

Our Astronomical Column : —

The l.ynil Meteors . .

A .New Form of Zenith Telescope

The < )rii>n Nebula ■ ; '„ ' i'

The Suns Place in Nature. III. {IlliislraUd.) By J

Norman Lockyer, C.B., F.R.S

The Institution of Naval Architects .■■•••
Questions bearing on Specific Stability. By Dr

Francis Gallon, F.R.S . .

A New Determination of the Ohm . .

The Smithsonian Institution Report for 1894 . .
University and Educational Intelligence ....

Scientific Serials ■

Societies and Acade^mies. (Illustrated.) 55^

SS3
554
555

556
557
557
557

557

558
558
558

564
564
564

568

57°
57!
57'
572
573

the properties of »alts of nickel and cobalt, by M. de Koninck. -^ t>.,-.„.M

A priority claim.— On the alcoholates of lime and baryta, by I Books and Serials Received

MO. 1328, VOL. 51

NA TURE

577

THURSDAY, APRIL i8, 1895.

THE EXPERIMENTAL PHYSIOLOGY OF
PLANTS.

Practical Physiology of Plants. By Francis Darwin,
M.A., F.R.S., and E. Hamilton Acton, M.A. Cam-
bridge Natural Science Manuals, Biological Series.
(Cambridge : University Press, 1894.)

THE physiological course which Mr. Francis Darwin
gave at Cambridge in 18S3, was the first sys-
tematic effort, in this country, to teach the phenomena
of plant-life to students by means of actual experiments.
As we are told in the preface to this book, the experi-
ments were at first demonstrated in the lecture-room ;
some years later, the students were required to do the
practical work for themselves in the laboratory. The
example set at Cambridge has been followed in other
universities and colleges, to the great benefit of botanical
teaching. We all recognise now that practical laboratory
work is no less necessary in physiological than in mor-
phological botany, though in the former it is certainly
more difficult to organise. The present book, which
embodies the results of the experience gained in prac-
tical teaching, is in two parts. Part i., on General
Physiology, is the more elementary, and therefore the
more widely useful ; Part ii., on the Chemistry of
Metabolism, is of a more advanced character, and is
adapted to those students who desire to make a special
stuJy of the chemical physiology of plants. The former,
we believe, is mainly the work of Mr. Darwin ; the
latter, of Mr. Acton. ^

A volume of this kind was very much needed, and it is
a matter for congratulation that the work has fallen into
the most competent hands. There was nothing of the
kind in English before, and the book will be of the
greatest service to both teachers and students. It must
be clearly understood that it is a strictly practical la-
boratory guide, which can only be used by those who are
willing to experiment for themselves. The volume is in
no sense a treatise on physiology, and thus differs from its
German predecessor, Detmer's " Pflanzen-physiologisches
Practicum," which is to some extent a compromise
"between a practical guide and a theoretical text-book.
The thoroughly practical character of Messrs. Darwin
and Acton's book seems to us a great merit ; every word
in it is of direct use to the experimental worker, and to
him alone.

We cannot attempt to give anything like a summary
of the contents of the work, which, in spite of its
moderate bulk, covers a great deal of ground. Thus in
part i. alone, no less than 265 distinct experiments are
described. Of course they vary very much in character,
some being quite simple and elementary, while others
are more of the nature of original research. It goes
without saying that a large proportion of the experiments
are of Mr. Darwin's own devising, and that nearly all
have been practically tested by the authors. Wherever
this is not the case, the reader is told so ; and if the
NO. 1329, VOL. 51]

experiment is, from any cause, at all likely to fail, he is
warned of the possible disappointment. The candour
with which the student is treated all through, is a very
pleasant feature of the book.

The first chapter is on some of the conditions affecting
t he life of plants, and as the presence of oxygen is
among the most important of these conditions, respira-
tion is taken first. Besides the more usual experiments,
ingenious demonstrations of intramolecular respiration,
and of the excessive consumption of oxygen by germinat-
ing oily seeds, are given.

In the second chapter assimilation takes the first place,
and many beautiful experiments are described, includ-
ing Gardiner's ingenious modification of Sachs's iodine
method, in which the sun is made to print off, in starch,
a copy of a photograph, from a negative placed on the
leaf. An experiment proving that excess of carbon
dioxide stops assimilation, is especially interesting.
When a second edition is called for, Mr. Blackman's new
and important experiments on the function of stomata
will no doubt find a place.

In the next chapter, which is also concerned with nutri-
tion, particularly good and complete directions are given
for the management of water-cultures ; these are quite
the best we have met with, and will save the experimenter
from many failures. The use of Duckweed {Lemna) for
demonstrating the effect of various food-solutions on
growth, is, we believe, new, and is a very neat method.
The same chapter includes experiments on the nutrition
of the carnivorous plant, Sundew, a subject on which
Mr. Darwin's investigations have become classical.

The question of the movement of water in plants is
still unsolved. The data of this problem, however, are
very thoroughly taught, by means of the experiments
described in the sections on the functions of roots, and on
t ranspiration. The latter process is investigated, in the
first instance, by means of the potometer, an instrument
devised by Mr. Darwin and his pupil Mr. Phillips, in
which the speed of the transpiration-current is measured
by the rate of ascent of an air-bubble, which is drawn up
a capillary glass-tube by a transpiring shoot connected
with it.

A particularly ingenious experiment is one in which
the hygroscopic twisting and untwisting of an awn of the
g rass Stipa, is made use of as an index of transpiration.

A chapter on physical and mechanical properties
tr eats of such phemonenaas imbibition, turgor, osmosis,
a nd the tensions of tissues. It may be pointed out that
in the description of Traube's artificial cells, copper
i ulphide is evidently a misprint, either for copper chloride,
<yc sulphate (p. 1 11).

The next chapter is on growth, and contains, among
ma ny other things, full directions for the use of the
various kinds of auxanometer.

The remaining chapters are concerned with curvatures
(geotropism, heliotropism, traumatic | curvature, &c.),
and with other movements. Some of the most fascinat-
ing experiments come in this part ; we will only mention
those on the decapitation of roots, an operation which,
as Charles Darwin discovered, prevents the root from per-
cei ving the geottopic stimulus, though it does not hinder

C C

578

NATURE

[April i8, 1895

the curvature of the growing region which may have been
induced by a previous stimulation. Attention is here
called to the brilliant experiments of Prof. Pfefler, which
have demDnstrated conclusively that the tip of the root
is alone sensitive to gravitation, thus finally confirming
the conclusion drawn by Darwin from less decisive ex-
periments. The announcement of this discovery by Prof.
Pfeffer was one of the most interesting incidents in the
Biological Section at the Oxford meeting of the British
Association.

A self-recording method for studying the sleep-move -
ments of leaves, strikes us as especially valuable.

The second part of the boo'c, on the chemistry of
metabolism, is of quite a diflferent character from part i.,
and is evidently intended for students with an advanced
chemical knowledge, who alone can make intelligent use
of it. The object aimed at is sufti:iently explained in
the opening paragraph :

"The practical study of the transformations which
plastic substances undergo in metabolism, is an applica-
tion of organic chemistry ; the immediate problem is
generally to determine whether certain substances are
present or absent, and, if present, in what am junts in
particular tissues."

The mode of determination of all the important
organic bodies occurring in plants, such as protein,
amides, oils, carbohydrates, tannins, acids, and enzymes,
is concisely explained.

There are two appendices, the first of which gives
examples of quantitative results obtained in actual ex-
periments, in order to show the degree of accuracy which
may fairly be expected ; the second is a list of reagents.

Within the short space of ninety small pages, which is
all that the second part occupies, it is obviously impos-
sible to give full instruction in such a difficult and com-
plicated subject as the practical physiological chemistry
of plants. Those, however, who are already good
chemists, will no doubt derive great help from the terse
directions given here, especially as these are supple-
mented by abundant references to the more special
literature.

The authors are much to be congratulated on their
work, which fills a serious gap in the botanical literature
of this country. We think it very desirable that a smaller
edition of the book should be published for use in
schools, bearing somewhat the same relation to the pre-
sent handbook as Prof. Bower's " Practical Botany for
Beginners" bears to his larger manual on the same
subject. It is most important, now that physiological
botany is supposed to be taught in so many schools
throughout the country, that it should really be taught
in the only efficient way, namely by experiment, and that
it should no longer be made a mere matter of " cram-
ming," as is now too often the case. A selection from
the present book of the simplest and most fundamental
experiments, such as could be performed with tolerable
certainty of result in ordmary science-schools, would, we
are sure, be of the greatest service to conscientious
teachers, who desire to make their scientific instruction

J.>v

D. H. S.

NO. 1329, VOL. 51]

MUSSEL CULTURE.

Mussel Culture and the Bait Supply, with reference
more especially to Scotland. By W. L. Calderwood.
(London : Macmillan and Co., 1S95.)

THIS little book has been written for the useful pur-
pose of calling public attention to the urgent need
of an increased supply of mussel bait in the interests of
the line fishermen, and in order that the food supply of
the country may be increased. It does not contain new
facts, but it summarises many old ones, and puts the
results of some biological inquiries in a form in which
they will be readily available for consultation by
members of County Councils and others who ought
to be interested in fish-culture. The general conclusion
arrived at is one which has been recently pointed out in
the pages of Nature, viz. that a systematic cultivation
of our foreshores, such as is now carried on in several
European countries — ^notably France and Holland —
must soon be resorted to if we wish to stop the rapid
depletion of our shellfish beds.

Sixty years ago the supply of mussels for bait must
have seemed almost inexhaustible, but now that larger
boats with more men and much longer lines are employed,
the supply of bait is rapidly failing at many places round
the coast, with the result that we have to import at con-
siderable expense large quantities of mussels annually
from Holland. The fact that it is necessary thus to impor t
a mollusc which grows naturally in great abundance
on our own shores, is in itself significant of the mis-
management—or total absence of management — of our
bait beds in the past. Mr. Calderwood gives an account
of the various mussel scalps or beds round the Scottish
coast, describes their former extent and their presen t
condition — in most cases a sad story of wicked waste
resulting in woful want — and says : " We have seen our
public oyster fisheries slowly decline, and all but expire ;
we now are watching our mussel beds as they diminish
in the same way."

It is a pleasant relief to notice that some few
beds really arc regulated and well managed, with
the result that they are in a flourishing condition.
For example, those at Montrose, where "the grounds
now under cultivation were at one time all but destitute
of mussels, but by the exertions of the Ferryden and
Usan Society of Fishermen, led by Mr. James Johnston,
'seed' was collected and bedded, and the system of
cultivation adopted which has since yielded such excel-
lent results" (p. 24). The interesting account of the
enterprise of the fishermen at Nairn, in experimenting
with mussel culture on their own account, shows how
readily new beds may be formed and important results
obtained. If such work is to be done, however, to any ,
great extent, we must adopt the French system of rent-
ing, on easy terms, the sea-bottom and foreshore to such
individuals as will cultivate the beds, and so render
them of increased value to the country.

We are reminded by Mr. Calderwood, as a proof
of the enhanced value of bait, that the sands of
Dun, in Scotland, which were not considered by
the fishermen to be worth £s a year at the beginning
of the century, are now let for ^S^° PC annum. Of

April i8, 1895]

NA TURE

579

the various baits for the long lines — mussel, scallop,
squid, lugworm, whelk, cockle, &c. — mussel is the
i most generally distributed, the most easily grown, and
altogether the most serviceable and important. The
Mussel Commission stated in 1889 that " nearly all the
50,000 fishermen of Scotland use mussels as their bait
during some part of the year." It has been calculated
that the fishing lines used in Scotland in 1893 would, if
tied together, nearly encircle the world twice, and
probably about 47,000,000 hooks have to be baited (each
with two mussels) every time all the lines are set. These
statements give some rough idea of the magnitude of the
demand for this bait. If squid could be obtained in suffi-
cient quantity, it would probably be even more valuable
than mussels, but its price is usually prohibitive to most
fishermen. .-V fishing firm in Aberdeen paid during this
last winter over ^200 for squid bait for a single boat's
, lines for the three months October to December, and
! there are fifty to sixty of such boats north of the
Tyne.

One section of this book gives a short account of the
anatomy, and the reproduction, and an outline of the
development of the mussel. Most of this is very simple ;
but it is not easy to understand the following statement
(p. 44), where, speaking of the kidneys, Mr. Calderwood
says : " Two internal openings also communicate with
the cavity in which the heart is situated, and in this way
the organ has a more powerful action in aerating the
blood " ! Whether " the organ " in question is the heart
or the kidney is not very clear, and in either case the
statement is equally mysterious.

As a single female mussel produces two or three

million young, and as innumerable young mussels all

round our coast perish miserably every year for want of

suitable objects to attach to, there can be no reasonable

doubt that the judicious erection of simple stakes, or

'' bouchots," would serve a useful purpose, at any rate in

the collection of seed, even if the further rearing be

carried on by means of the bed system. The import-

i ance of transplanting, of cropping the beds by rotation,

I of exterminating enemies such as starfish and wheiks,

1 and of avoiding overcrowding, is pointed out ; and we are

reminded of the opinion of Prof MIntosh, endorsed by

the Scottish Fishery Board, that " if properly and wisely

I managed, a mussel fishery will rapidly repay the small

I initial expense, and might, indeed, be made largely

profitable."

The book concludes with a chapter on the legal aspects

i of the matter, extracts from the Acts in regard to mussel

fisheries, and information on the methods of obtaining

'fishery "orders" in England, Scotland, and Ireland.

Some of these legal processes seem unnecessarily com-

j plicated and expensive, and it is certainly unfortunate

[ that our local fishery committees can make regulations

I in regard to their mussel beds, but cannot improve

I them by cultivation ; and yet in parts of England the

I mussel is even more important than in Scotland, as it is

( used not merely as bait, but very largely as food in some

districts. The book seems singularly free from typo-

! graphical errors — a curious slip on p. 1 1 suggests that

the author's mind was so full of his subject that he has

mis-spelled Mr. Bateson's name. W, A. H.

NO. 1329, VOL 51]

HISTORICAL EPIDEMIOLOGY.
A History of Epidemics in Brilain. By Charles

From the Extinction
Time. (Cambridge :

Creighton, M.A., M.D. Vol. ii.
of the Plague to the Present
I University Press, 1894.)

THE first volume of this work was reviewed in these
columns about three years ago, and Dr. Creighton
has now brought his difficult task to completion. The
labour of disinterring the facts of epidemiological
history from the scattered chronicles in which they
lie hidden is very considerable, and, when this is
accomplished, the historian is further confronted with
the difficulty of identifying, under the confused nomen-
clature of by-gone days, the various pestilences described,
and of assigning to them their proper place in modern
nosology.

Dr. Creighton has undoubtedly earned the thanks of all
students of epidemiology for the painstaking and laborious
compilation of facts and references which he has brought
together in the present volume. The magnitude of the
labour has been immense — the more so since, as the
author remarks in the preface, he has had little help from
predecessors in the same field. He has at times in-
corporated with the strictly historical portions of the
work aetiological considerations which, we fear, will
hardly commend themselves as of equal merit with the
rest ; these, however, form but a small part of the whole,

j and though they call for comment, should not be allowed
to interfere with our appreciation of the value of the

'■ book.

The opening chapter deals with typhus and other con-
tinued fevers, and its historical interest is very great. It

, well illustrates the close connection which exists between

' the epidemic prevalence of this group of diseases, and
the physical environment and social conditions of the
population, nor could an instructive lesson in hygiene
have been better presented. It is interesting, too, to
trace the gradual rise of more exact pathological
notions, whereby the old medley of spotted, putrid,
miliary, and comatose fevers has been resolved into our
modern typhus, enteric, and relapsing fevers. The
grouping together of influenzas and " epidemic agues "
in another chapter seems warranted by the etymology of
the term ague (Latin : acutus), the expression being used

I in early times for any sharp fever : the term "influenza"

' did not reach England till 1743.

I Small-pox naturally receives a full measure of attention.
The statements put forward to show that during the
seventeenth century the mortality from this disease had
not that excessive incidence on infants which afterwards
became the rule, are not, in the necessary absence of any
statistical evidence, sufficiently convincing. The history
and practice of inoculation are treated of at great length,
and the account is full of interest. Dr. Creighton's
opinions on the subject of vaccination are well known,
and it is a pity that in a purely historical work, any bias
should have been allowed to appear. He has perhaps
done his be5t to avoid it by treating vaccination, after
the year 1825, as "^r //y/t^/Zic'jv irrelevant," though this
proceeding may raise a smile on the faces of many of his
readers. Even in the preface the assumption that variola

58o

NA TURE

[April i8, 1895

and vaccinia are two perfectly distinct diseases, calls for
some comment in the light of recent investigations, and
the omission of any reference to the statistics of the
Sheffield epidemic of 18S7-8 is a serious blot on any
work dealing with the history of small-pox. The im-
munity from small-pox which infants and children enjoy
at the present day, receives the not very satisfying ex-
planation that they now have measles, whooping-cough,
scarlatina, and diphtheria instead !

In the later chapters the author deals with the last-
mentioned diseases and with infantile diarrhoea,
dysentery and cholera, the history of which is traced
with great care and accuracy. It would indeed be
difficult to praise too highly the pains which the author
has taken in the collection and arrangement of his
historical facts. But he has chosen to add, in many
places, considerations as to the nature and causes of the
diseases he chronicles, which frequently do not cover all
that is known about the subject, and would have been
better omitted or treated separately from the historical
portions of the book. It is true that, in some cases, there
are strong reasons for believing that the virus of a disease
may reside in the soil, but it is by no means true for
others. It is true that we are ignorant of the precise
nature of the virus of many of the diseases discussed in
the book ; but it is not the case with all. Yet in no
single passage dealing with atiology do we find any
reference to even well-established bacteriological facts.
It may be that much studying of the records of the past
begets a tendency to a medieval frame of mind. Cer-
tainly Dr. Creighton's views on telluric influences will
■ not commend themselves to the modern pathologist,
though, like the subjects he treats of, they may possess
a historical interest.

But it is a great merit of the book that it can be
read with pleasure and instruction by all, however the
reader may differ from the author in pathological creed ;
and Dr. Creighton may be congratulated upon the com-
pletion of so excellent and thorough a history of epidemic
diseases in this country.

OUR BOOK SHELF.

Crundziige der mathemalischen Cheniie. Von Dr. G.
Helm. (Leipzig : Wilhelm Engelmann, 1894).

The treatment of the subject-matter of this book is based
on the view that in its present state of development, that
branch of physical chemistry which relates to chemical
change can be di?cussed from a general standpoint, in-
asmuch as it affords the clearest and most complete
confirmation of the principle of the conservation of
energy.

The applications of this principle to chemical inter-
actions arc first illustr.ited by means of the different kinds
of thermal measurements, numerical examples being
given, the solutions of which, here as elsewhere in the
book, are particularly neat. Mechanical forms of energy
attending chemical change, in particular the volume
energy of gases, are also discussed. The author next
points out that the measures of the different forms of
energy are composed of two factors, one of which is all-
important in determining the direction of the energy
change. Temperature and entropy are shown to be tlie
factors of heat energy, and a clear and concise account
of the thermodynamics of perfect gases is given, in order

NO. 1329, VOL. 51]

to arrive at the shape of the entropy function, which is
of course known in this particular case. The relations
between heat energy and volume energy, and between
heat energy and electrical energy, are then set out at
length.

The author here indicates how terms involving what
he calls the "chemical intensity" of the reacting sub-
stances enter into the energy equations. Chemical
intensity is what Gibbs originally termed the " potential "
of the substances, and this function, it is hoped, will
eventually be shown to be the mathematical expression
of chemical affinity.

The third section of the book is devoted to the pro-
perties of chemical intensity. The general method of
deriving the law of mass action is given, and chemical
equilibrium, the properties of dilute solutions, and the
velocity of chemical reactions are brought under the
sway of the energy equations. The last section contains
the treatment of the phenomena which may be grouped
around Gibbs's phase rule, and of reactions depending
on several parameters.

The book is the only one which is exclusively devoted
to chemical energetics, and to the student possessed of
sufficient mathematical knowledge it offers an admirable
account of the present state of the subject. J. W. R.

Die Bearbeiiung des G/ases auf dem Blasetischi: Von
D. Djakonow und W. Lermantoff. Pp.154. (Berlin:
R. Friedliinder and Sohn, 1895.)

The original edition of this book was in Russian, and
the authors, one of whom, D. Djakonow, is now dead,
were demonstrators in chemistry at St. Petersburg Uni-
versity. The instruments and methods employed by
glass-blowers are set forth in detail, together with de-
scriptions of the kinds of glass best suited for different
work. A very full and practical account is given of the
construction, graduation, and calibration of thermo-
meters ; but to carry out these operations thoroughly,
some experience is required. Work more suitable for
the 'prentice hand fills the greater part of the book.
Every operation in glass-blowing and manipulation likely
to be needed in physical and chemical laboratories,
appears to be described ; while the diagrams illustrating
the stages in the construction of the different pieces of
apparatus, will greatly assist in training students to
become skilled workers.

Problems and Solutions in Elementary Electricity and
Magnetism. By W. Slingo and A. Brooker. Pp. 108.
(London : Longmans, Green, and Co.)

Model answers to examination questions may prove a
blessing or a curse, according to the way in which
teachers use them. Herein are answers to questions in
electricity and magnetism (elementary stage), set at the
Science and Art Department's examination from 18H5 to
1S94, together with a series of original questions. The
teacher who wishes to train his class to answer ques-
tions clearly and concisely, will find suitable exercises
in composition in this book, and he will also find the
volume an inducement to cram his students with
undigested information.

Qualitative Chemical Analysis of Inorganic Substances.
" (New York : American Book Company, 1895.)

This work consists of a series of analytical tables, sup-
plemented by explanatory and descriptive notes, and
working directions. It makes no pretence to originality,
and is hardly a book wc should like to see widely adopted
by students of elementary practical chemistry. The tables,
which were prepared (or use in Geort;ctown College,
Washington, D.C., present few points o( interest or
value to teachers ol chemistry in our schools.

April i8, 1895]

NA TURE

;8i

LETTERS TO THE EDITOR.

Th: Editor does not hold himself responsible for opinions ex
pressed by his correspondents. Neither can he undertake
to return, or to correspond with the writers of, rejected
manuscripts intended for this or any other part of Nature.
No notice is taken of anonymous communications.]

Professor Boltzmann's Letter on the Kinetic
Theory of Gases.

In common, I am sure, with all the physical readers of
Nature, I have read Herr Bollzmann's letter with great
interest, .-^nd I am glad to observe that, though he appears to
think I differ from him, that part of his letter which chiefly
deals with my criticism on Dr. Watson's idea of what
" Boltzmann's Minimum Theorem " is, is simply putting
forward, with all his great authority, the view for which I
contended. Bat it is a liitle hard that Dr. Boltzmann should
represent me as endeavouring to disprove his theorem when I
expressly slated that while I did not know his proof, 1 supposed
that it was all right. True, I said that I found it hard to
conceive how any proof on the lines of Dr. Watson's could be
valid because that proof appeared to me to be a purely dynamical
proof, and I applied the reversibility argument to show that a
purely dynamical proof was impossible, io that the H-theorem
could not be a purely dynamical theorem ; and after indicating
the lines on which it appeared that there might be an average
dynamical theorem, I asked if some one would say what the
H-theorem really was.

Thereupon Mr. Burbnry wrote a helpful letter, which he
followed up by a still more helpful correspondence, in which
verbal misunderstandings were gradually cleared away, which
showed that the proof of the Il-theorem considered as a
dynamical theorem, not as a theorem in probabilities, assumed
that in one respect the configuration was, before each set of
collisions, already perfectly average, and that this condition is
violated in the reversed motion ; so that the theorem, regarded
as a dynamical theorem, is not proved for configurations in
general, but for those possessing a certain amount of "average "
already — a restriction which comes to the same thing as the
limitation imposed by Prof. Boltzmann when he says the
theorem is not a dynamical theorem, but one in probabilities.

Shortly after Mr. Burbury's letter appeared, Dr. Watson
wrote denying that the criticism from reversibility applied,
and claiming that the theorem was a general dynamical theorem,
in the sense that it applied to all configurations. Enlightened
by Mr. Burbury, I now see that Dr. Watson's reasoning is
not open to the objection that it proves a general dynamical
theorem ; but I cannot blame myself for thinking that it did, for
that was what Dr. Watson himself believed it to do, and what
his language naturally implies. Moreover, after perceiving the
oversight which vitiates the proof io its present form, I did not
examine it further.

Prof. Boltzmann has misunderstood Mr. Burbury and me in
one or two particulars. He denies that there are as many con-
figurations lor which dHjdt is positive as there are for which it
is negative. He evidently thinks that we mean something
different from the bare meaning of the words, which are cer-
tainly true. It is easy to explain what we do not mean (I say
we, for I am sure Mr. Burbury will agree with me). Suppose
H=loto be the minimum value of H for a given system of
molecules, we do not mean that among all the configurations
for which H=:50, there areas many which will, if left to them-
selves, turn into configurations forwhich H =60, as will turn into
configurations for which H = 40 The illustration, which tomy
mind has most clearly removed the apparent contradiction
in the statement that there are as many configurations for which
H will increase as decrease, while yet the probability is that
H will on the whole decrease, is that of a j' turned upside down,
thus \. For every downward path there is an upward path.-
i.e. the reversed direction ; yet starting from the angle there
are two ways down for one way up, so that there is a greater
probability of going down than up. If in the reversibility argu-
ment one could assert, not merely that there are as many con-
figurations for which H tends to increase as to decrease, but that
for any given value of H there were as many configurations which
tend to increase as to decrease, then the conclusion that H was
ai likely to increase as to decrease could be deduced. But the
argument is quite invalid when we set off a configuration for
which H increases against one for which it decreases, although

the values of H for each are different. As an illustration more
closely allied to the case of a gas, we might take a tree turned
upside down, with an infinite number of branches passing
through each point of its substance in all directions, there being
at every point more branches tending downward than upward
(because those whose tangents are horizontal may be said to
tend downward on each side), and every upward branch finally
turns downward and tends to become nearly horizontal at last,
when H is near its minimum value.

To my mind this appears a far better way of meeting the
difficulty than Prof Boltzmann's illustration of the dice, for so
far as 1 can see, all that he has shown is that if you start from
an exceptionally high ordinate, i.e. one over the average,
you are likely, after a considerable time, to get to lower
ordinates in whichever direction you go, and an opponent
might answer that if you start from an exceptionally low
ordinate you are likely to get higher ones in whichever direc-
tion you go, and that there must of course be as many deviations
below the average as above it, so that if you start from an
arbitrary point in an arbitrary direction, you are just as likely to
get to higher as to lower ordinates. In point of fact this
appears to be the case for his curve, while it is not true for the
tree or for a gas.

Prof Boltzmann must have put an entirely wrong construction
on something or other, which I suppose I have written, when
he says I object to the Maxwell Law of distribution because it
would ultimately lead to the total kinetic energy of the universe
being equally distributed among every degree of freedom of
every particle in the universe. Instead of considering that to
be a priori im-pxoh3h\e, I hold exactly the view put forward by
Prof. Boltzmann.

With regard to the first portion of Prof. Boltzmann's letter,
there is so much that is speculative in it that any discussion
would occupy more space than I feel entitled to claim. 1 will
only say that the idea th at a gas takes years to con.c .0 thermal
equilibrium seems hardly consistent with vibrational portion
of the kinetic theory being of practical value, when applied to
gas which has only had a few hours to settle down.

Edward P. Culverwell.

Trinity College, Dublin, March 6.

It seems to me that my meaning has not been expressed quite
clearly ; therefore, it may be worth while to add one remark.
Not for every curve, but only for the paiticular form of the H-
curve, disymmetrical in the upward and downward direction,
can it be proved that H has a tendency to decrease. This
particular form is very well illustrated by Mr. Culverwell's
suggestion of an inverted tree. The H-curve is composed of a
succession of such trees. Almost all these trees are extremely
low, and have branches very nearly horizontal. Here H has
nearly the minimum value. Only very few trees are higher,
and have branches inclined to the axis of abscisss, and the im-
probability ot such a tree increases enormously with its height.
The difficulty consists only in imagining all these branches
infinitely short.

Finally there is the diflerence between the ordinary cases,
where H decreases or is near to its minimum value, and the very
rare cases, where H is far from the minimum value and still in-
creasing. In the last cases, H will reach, probably in a very
short time, a maximum value. Then it will decrease from that
value to the well-known minimum value.

Paris, .'^pril 6. LUDWIG Boltz.maNN.

The Recent Auroral Ph enomenon.

On the evening of March 13, from 7.35 to 8.5, Greenwich
mean time, I was a spectator of the abnormal display of Aurora
Borealis which attracted so much attention at various places
throughout the country. It appeared here as a belt of light
spannmg nearly the whole sky in a great circle from east to
west. When first noticed by me at 7.35, the streak extended
from near the hind quarters of Leo to the head of Aries, or
from K..\. 169°, Decl. -I- 16" to K.A. 24', Decl. + 22°.

At the time the streak was altogether cometary in appear-
ance, beginning in a fine point, but it gradually changed in
form, moving at the same time towards the south. Eventually
it also shortened so considerably that just before my last view
of it, it only extended from 7 Geminorum to 7 Ceti. Its greatest
breadth was about 12°.

NO. 1329, VOL. 51]

5J52

NATURE

[April i8, 1895

The following figures represent the most striking phases, as
nearly as may be at intervals of five minutes.

Fig. I shows how the streak extended from the cometary
head so as to form a long wavy tail, and represents also the
streak at its greatest length. As indicated in the sketch, there
was a central portion much more brilliant than the rest, running
from the head into the body of the streak.

In Fig. 2 the streak is seen when it had more the appearance
of a rainbow than of a comet ; and it was verv noticeable that
one side — that towards the north — was much brighter than the
other.

Fig. 3 shows how the "head" began to shrivel up — shorten-
ing the streak. The glimmering appearance of the "shrivel-
ling " put me very much in mind of the motion of the air over
a "hot heap" (of slag); the tail end began to broaden out
somewhat.

In Fig. 4 the streak has taken a very pronounced arrow-
headed .shape, and, as if to complete the resemblance, the

North.

Fig. I.

Fic. 2.

Fic.

Fig. 4.

South.

Fic;

shimmering part look the form of the feathering ; whereas in
the preceding figure it had more the appearance of combteelh.
The more brilliant parts are indicated hy daiker shading.

In Fig. s the streak has consideiaMy shortened and
broadened out in the west, where it soon alterwauls mingled
with faint auroral rays which had come round from the northern
horizon.

I may lay, in general, that the appearance; were singularly

and hrillianl. The sky was very clear at the time,

■ ;ar wa.s visible through the most brilliant parts of

- Inuring the time the streak was visililc there was a

(aint rii-play of aurora on the northern horizon, which, as I
have already said, worked round lo the west and cau>;hi the
la»t of the streak. Jas. G, Richmond.

Muirkirk, N.B.

NO. 1329, VOL. 51]

THE AGE OF THE EARTHS

TLL-HEALTH has hitherto prevented my making the
^ comments which seemed called for by Lord Kelvin's
friendly article of March 7, in reply to my communi-
cation of January 3. Perhaps I may be allowed not
merely to restrict my remarks to this article, but to
deal more generally with the subject, in the hope of
clearing away the misapprehensions which exist between
modern geologists and palxontologists, who are no
longer uniformitarians, and physicists who are repre-
sented by Lord Kelvin.

The arguments as to the age of life on the earth are
based on considerations of (i) geology and paleontology ;
(2) tidal retardation and shape of the earth ; (3) the
cooling of the earth from an initially hot condition ;
(4) the age of the sun.

(i) From geology. The leading geologists declare
that the great thickness of sedimentary rocks created
since the Lower Cambrian, which are almost the oldest
fossiliferous rocks, can only have been produced during
iTiany millions of years.

It is difficult to get geologists to give even wide
limits for the age of the Lower Cambrian.-' Their calcu-
lations are based not upon the rate of accumulation
of sediment in one of our quiet oceans, but upon
the rate of degradation in valleys where the rate is
greatest at the present time. They make this declara-
tion, thinking that for thclast thirty three years it has been
authoritativelydeclaredby physicists that such anestimate
is absurdly great. I have no doubt that they have done
their best to keep this estimate as. low as possible, for
they have a great interest in making geological theory
agree with physics. Some physicists tell them that the
flaw in the geologists' reasoning consists in their not
taking into account the much greater tidal actions of
the past. When tides rose and fell many hundreds of
feet, and swept over tens or hundreds of miles of fore-
shore, there must undoubtedly have been a more
rapid formation of sedimentary rock than anything of
which we now have experience. The geologists' answer
is : — We acknowledge th \t all nature's actions were
on the whole, possibly, more intense in the past. We
know from Prof. Darwin's development of Prof. Purser's
theory that the moon was undoubtedly nearer the earth
in palaeozoic times, and the tide influence was there-
fore greater. But there seems to be no method of
even approximately calculating how much greater the
tidal influence was. Whilst one great astronomical
authority speaks of tides of 500 feet deep in pala;ozoic
times, Prof. Darwin himself thinks that two or three
times as great as at present may be an excessive estimate.
There is a good deal of geological evidence for much
smaller seas than at present, and even if tidal influence
were greater the actual tides may have been much
smaller than now. Of positive evidence in our favour,
we have the fact that numerous examples exist of
palaeozoic locks which are identical in almost every
physical way with tertiary rocks, and it is difticult
to believe that they can have been deposited under
very different conditions. Again, nearly all the old
sedimentary rocks were laid down near coasts where
tidal action would be inost violent. Yet even low
down in the Cambrian we find the remains of creatures

' I n this paper free uuc has been m.idc of many suKKC^'tions from Prof.
Filrg'-mld,

" I'hcir data arc i.f this nature • — Of fossiliferous rocks successively
formed the !• tal thickness may be laken as not less than 80,000 feet. Over
Ihc areas of the t);uiii . ilrained by many rivers ihe rati- of deniidatinn is
kno ' n witli -uffi. ienl accuracy for apprdxiniatetalciilaiioii. ofthcl)asio
of the Mississippi a thickncs> of one foot of rock i^ reinuved in 6000 years :
Ihr Ganges, 3J58; the Ho.inK Ho. 1464 ; the Rhojic. 1518; the Danube,
CB^O; the I'o, 7^9: ihe Nilh, 4733 (Sr A. Geikie, (.Jc-ol. .-oc. of Gla-gow.
18(8). I have heard that I'rol. .Sollas dcmaod> Ic-s time th.an other
grolo^isis : t^ut since tt-is paper was written, I have setn (Nai URE, April 4)
that even he does not care 10 put the age of the Lower Cambrian at inncb
less than 17 million years.

April i8, 1895]

NATURE

58:

which still have attached to them delicate antennas. In
sandstones we find most delicate ripple marks and the
marks of rain-drops. But over and above all this,
denudation along coast-lines can hardly be regarded as
of much importance compared with subaerial denudation
(Sir A. Geikie, Trans. Q^a\. Soc. of Glasgow, iS68).
Was there more rain .' and did it fall more suddenly .'
Did the wind blow more strongly .' Were atmospheric
actions more vigorous in the past ? There is no great
reason for believing that they were. As Prof G. Darwin
observes, fossil trees do not seem to have been built
more strongly than modern trees, and this gives some
evidence as to the relative violence of aerial forces.

All the geological evidence points to rates of denuda-
tion and deposition in the past which may, on the average,
have been greater than the average rate at present, but
which were not on the average greater than the greatest
rates at present.

The pakcontologist now comes in. A study of fossils
shows that there has been a gradual development, some-
times more quickly perhaps, and sometimes more slowly,
but on the whole a continuous development of animal
life in the past. We believe from all our study of nature
that the development has been continuous. As more
and more strata are studied, many of the apparent dis-
continuities are being converted into continuities. Now
even in the lower parts of the Cambrian, Brachiopoda are
found. Biologists tell us that in all probability these
were gradually developed from creatures like worms ;
their structures are sufficiently comple.x for us to know
that the time taken to develop the Brachiopod from the
worm may have been as great as the age of known
fossiliferous rocks. There are many rocks, evidently
sedimentary, enormously older than the Cambrian, and
when laid down there was certainly water on the earth,
and hence it was neither too hot nor too cold for animal
life. In these lower formations there are conglomerates
containing pieces of still older rocks. Although in pre-
Cambrian strata traces of animal remains are said to
occur, we may say that the pateontological record is
almost lost below the Cambrian, most of the earlier rocks
having been subjected to great metamorphic action.
If we keep to our principle of continuity in nature's
actions, we see that the first beginning of life must have
taken place at a date many times earlier than the very
earliest geological record.

But the most experienced geologists and palasonto-
logists state that they are satisfied with a i^vi hundred
million years as the possible age of life or the existence
of water on the earth.

2. The considerations drawn from tidal retardation
are as follows : — ■

(a) The shape of the earth now is the same as its shape
when it solidified, [fi) The shape of a liquid earth tells
us its rate of revolution on its axis, therefore we know
the rate of revolution of the earth on its axis when it
solidified. (y) Assuming that we know, with a fair
amount of accuracy, the rate at which the length of the
day is altering, we know the date of the earth's solidi-
fication, and certainly this is later than looo million years
ago.

When I referred to the fallacy in this argument,
I did not know that it had already been pointed out by
the Rev. M. H. Close and Mr. Clarence King and Prof.
George Darwin. It lies in the fact that (n) is certainly
wrong. A solid body like the earth will, under the action
of great forces, alter its shape in time. Such alteration
is continually going on. Again (y) is very doubtful.

(3) 1 now come to the considerations from the cooling
of the earth. Lord Kelvin proved that, if the earth was
once at a uniform temperature of 7000' F. or 3S70" C, of
material the heat properties of which are the same as the
average of three rocks experimented upon at Edinburgh
— these remaining constant throughout — and if the rate

NO. 1329, VOL. 51]

of increase of temperature downwards in the crust is now
I Centigrade degree for every 90 feet, 100 million years
have elapsed since cooling began ; but there is a possible
maximum of 400 millions.

In the article on this subject, published in Nature,
January 3, 1895, I showed that, if we assume greater
conductivity in the interior than at the surface, we in-
crease this limit of age. I took a number of examples,
which could be worked mathematically. I did not pre-
tend that any one of these represented the actual state
of the earth. They merely proved that there were
i)ossible internal conditions which might give enormously
greater ages than physicists had been inclined to allow.
Of my various results, I did not give one as more correct
than another, although some may have seemed more
probable than others. It was not my object to obtain a
correct estimate. Indeed I tried to show that it was im-
possible for a physicist to obtain such an estimate, as
there were all kinds of possible assumptions which led to
many different answers.

The validity of my reasoning in no degree rests upon
the accuracy of R. Weber's results as quoted by me. In-
deed, I only discovered these results when writing to Prof
Tait. In N.-^TURE, February 7, p. 341, I have shown the
extent to which the possible limit of the earth's age is
increased if k and c increase with temperature and
k c remains constant. But I published this as an in-
teresting mathematical result, and was careful to add — •
" It must be understood that my conclusions are really
independent of whether R. Weber's results are correct or
not.'' It is comparatively unimportant, but R. Weber
has published another set of results which confirm those
which I quoted. The results, published on March 7
for the first time, differ so utterly from the two previous
sets, that I venture to think there may be mistakes in
transcribing. However that may be, I am not concerned
either to support or refute them.

I mentioned the possible great quasi-conductivity due
to the interior of the earth being a honey-combed mass
containing liquid, and to the possible greater con-
duction due to the presence of iron and other metals.
Almost anything is possible as to the present internal
state of the earth. Dr. Ramsay seems to think that
there must be great quantities of sulphides inside, and
these would probably be much better conductors than
the surface rocks.

Prof. Schuster, in discussing the diurnal variation of
terrestrial magnetism {Phil. Trans. 1889, p. 467), comes
to the conclusion that the electric conductivity of the
earth must be considerably greater inside than at the
surface.

In all probability there are no great masses of liquid
inside the earth at the present time, but it is quite
possible that until recent times convection in such masses
may have been conveying heat from the very inner earth
towards its surface, and the latent heat given out by such
masses of liquid as they solidified would be another
potent factor. Some distinguished geologists say that the
e.xcessive folding which has occurred on the earth's sur-
face cannot be accounted for by the current assumption of
physicists, which involves the result that, practically, no
cooling has yet taken place below the depth of 120
miles : my assumption is that cooling has taken place to
much greater depths.

All these things, like the numbers published by R.
Weber, support the argument if they are correct, but
they do not in any way destroy it if they are wrong. I
was not looking for ^. probable age of the earth from the
point of view of mere physics. 1 wished to show that the
physics' higher limit was greater than a few hundred of
millions of years.

Mr. Clarence King's paper appears somewhat incon-
clusive. He assumes, possibly rightly, that the earth's
crust may have the properties of Diabase ; experiment has

5S4

NA TURE

[April 18, 1895

shown what is the rate of increase of the melting tem-
perature with increase of pressure of this rock : Laplace's
hypothetical l?.w of increase of density downwards in the
earth cannot be ver>' wrong, and from this a law of in-
crease of pressure downwards may be formulated. From
these data Mr. King finds what are the temperatures at
various depths, which if exceeded would mean liquidity.
A liquid layer inside the earth's crust being assumed to
be impossible, Mr. King, trying all sorts of Kelvin solu-
tions of a solid earth of uniform conductivity and
uniform temperature, initially finds a maximum age of 25
million years, the initial temperature being not greater
than 2000" C. ! Furthermore, higher initial temperatures
are not possible !

Now it is evident that if we take any probable law of
temperature of convective equilibrium at the beginning
and assume that there may be greater conductivity
inside than on the surface rocks, Mr. King's ingenious
test for liquidity will not bar us from almost any
great age.

(4) There remain, lastly, considerations drawn from
the age of the sun. On the assumption that all the
energ)' possessed by the sun was that due to the mutual
gravitation of its parts, and that the sun is now of uni-
form density, Helmholtz found that the sun may have in
the past radiated as much as 22 million times his present
annual loss. Langley found that the sun's present rate
of radiation was under-estimated, and the statement of
Prof. Newcomb may be taken as that of Helmholtz,
corrected. Newcomb says (" Popular Astronomy," p. 523):
" If we take the doctrine of the sun's contraction as fur-
nishing the complete explanation of the solar heat during
the whole period of the sun's existence, we can readily
compute ... It is thus found that if the sun had, in the
beginning, filled all space, the amount of heat generated
by his contraction to his present volume would have been
sufficient to last iS million years at his present rate of
radiation."

Lord Kelvin pointed out (pp. 364-65, vol. i. " Pop.
Lectures") that Helmholtz had assumed a sun of uniform
density, whereas the sun's density must increase very
much towards his centre, and as a result of cal-
culation on the assumption that only half of the
original energy was available (p. 374), that the
radiation was greater in the past, and that the
original collisions occurred practically simultaneously,
he says : " We may therefore accept as the lowest esti-
mate for the sun's initial heat 10,000,000 times a year's
supply at present rate, but 50,000,000 or 100,000,000 as
possible, in consequence of the sun's greater density in
his central parts." And again (p. 375) : " It seems there-
fore, on the whole, most probable that the sun has not
illuminated the earth for 100,000,000 years, and almost
certain that he has not done so for 500,000,000 years.
This last number, then, is Lord Kelvin's higher limit.
After six years, in 1868, Lord Kelvin returned to the
question, and he says (p. 53, vol. ii. " Pop. Lect. and
Addresses ") : " The estimates here are necessarily very
vague, but yet vague as they are, I do not know that it
is possible, upon any reasonable estimate, founded on
known properties of matter, to say that we can believe
the sun has really illuminated the earth for five hundred
million years."

In his R.I. address of 1887 Lord Kelvin gave no
higher limit. I think that, on his specified assump-
tions in giving these large numbers, he has been
very generous ; for, taking Mr. Homer Lane's deter-
mination of the internal density of the sun, 1 find that the
Helmholtz total energy need only be nmhipUed by
about aA. If, however, instead of taking, as Mr. II. Lane
did, v\ as the ratio of specific heat, we take a less
number, and there is no reason why we should not, we
find much greater densities towards the centre, and a
much greater total energy and age. Still, I think ili.it it

NO. 1329. VOL. 51]

is only when we escape from the above assumptions that
we can see our way to increase the higher limits which
have been quoted.

To justify the Helmholtz hypothesis of mere mutual
attraction, initially, between the portions of matter which
form the sun. Lord Kelvin (" Pop. Lect.," vol. i., pp.
41 1-3) dwells upon the great improbability that any parts
of the sun possessed much initial velocity. He shows
that if two bodies, A and B, came together to form the
sun, when the bodies were still far apart before collision,
the motion of the centre of B relatively to A, must have
been directed with great exactness to pass nearly through
the centre of A (as the sun has a comparatively small
moment of momentum), and this was very improbable
if the bodies had initial velocities. But this argument is
only satisfactory when the bodies coming together are
two in number. For example, let us imagine in early
times a sun of half the mass of the present one, but of
many times its diameter. It is possible that its radiant
energy was supplied by meteors. If the meteor feeding
was in excess, the sun- became larger in volume. If
there was too little meteor feeding, the sun became
smaller. Even if there was a very excessive supply for
a short time, say by the incoming of a huge meteor, we
need not assume excessive radiation in consequence.
Such meteors may have come from stellar space with
great initial velocities, and may have possessed before
collision many times the kinetic energy which a
mere solar system meteor of the same mass would
possess.' If there were many such meteors, their paths
might be enormously out of line with one another and
with the centre of the sun, and yet we need not imagine
them to alter much the moment of momentum of the
sun about its axis. If we look for the prolntble age of ]
the sun as deduced frotn mere physics, we ought to take
Helmholtz' condition of mere mutual attraction, the
Helmholtz calculation being corrected of course for
greater internal density ; but if we look for a higher limit
to the age of the sun, it is difficult to see why we may
not multiply Lord Kelvin's total energy and age of 500
million years.

Again, the ages determined by Von Helmholtz, Prof.
Newcomb, and Lord Kelvin, are given on the uniformi-
tarian assumption that the sun has been radiating energy
always at his present rate. If we may imagine that for
long periods the sun radiated at a smaller rate,
whether because his mass was smaller, or because
of his atmosphere, we again have an increase
to the calculated .age. Prof. Newcomb seems to
have noticed this, and to meet the objection
(p. 525, "Popular Astronomy") he says, "that a
diminution of the solar heat by less than one-fourth of
its amount would probably make our earth so cold, that
all the water on its surface would freeze, while an increase
by much more than one-half would probably boil the
water all away." On account of this exigency, indeed,
he reduces his previous estimate in the ratio of nine to
five. This statement ought to have the careful consider-
ation of men who know more about astronomical physics
than I do. It means that if the earth were now isi per
cent, further away from the sun, there would be no w.ater
and no life, only ice ; and if we were 184 per cent, nearer
the sun, there would be again no water and no life, only
steam. It becomes an important question, is there no
life, is there no water on the planet Venus which has
twice our solar radiation.' Is all its water in its .atmo-
sphere as steam? Again, Mars has only 40 per cent,
of our solar r.adiation ; is there no life, no water,
only ice upon Mars? I have no right to speak
on such a subject, but I understood that the atmo-
sphere of Venus was much like that of our own planet,
and that the water of Mars is not all ice, for his pol.ar

' The velocUici of «l.-irs are probubly much less than the possible velo-
cities of smaller bodies.

April i8. 1895J

NATURE

5«;

snow-caps are seen to melt in summer. True, they may
be solid carbonic acid, but I have recently read that the
green colour of vegetation had been observed to appear
and disappear regularly on the planet. If there is little
water on the surface of Mars, I should imagine that this
is rather due to its having soaked into the crust, which is
probably colder underground than ours. I'rof. Newcomb
has evidently not thought of Mars in this connection, for
elsewhere he says : " If there are any astronomers on
Mars . . ." On this question I venture to quote Lord
Kelvin, who said, in 1887 (" Pop. Lect," vol. i. p. 376),
that "the intensity of the solar radiation to the earth is
6i per cent, greater in January than in July ; and neither
at the equator nor in the northern or southern hemi-
spheres has this difference been discovered by experience
or general observation of any kind." It is difficult to
imagine that if the effect of 6i per cent, cannot be de-
tected, 25 per cent, should convert all the water to ice
and destroy all life.

Even if a small diminution of the solar radia-
tion produced a very cold climate on our present

heat convectively from considerable depths, this heat
again being carried about convectively by the earth's
atmosphere, keeping the solid parts of the earth's sur-
face in a fit state for the e.xistence of low forms of animal
life. 1 1 is possible that at the present time the surface
of Jupiter, which receives a very small intensity of solar
radiation, may have solid parts surrounding watery lakes
and oceans capable of supporting life because of the
existence of many lakes of melted lava.

To sum up, we can find no published record of any
lower maximum age of life on the earth as calculated by
physicists (I leave out the estimates based upon the
assumption of uniform density in the sun, and also
that of Mr. Clarence King; than 400 million
years. From the three physical arguments, Lord
Kelvin's higher limits are loco, 400, and 500 million
years. I have shown that we have reasons for believing

I that the age, from all three, may be very considerably
underestimated. It is to be observed that if we exclude

i everything but the arguments from mere physics, the
probable age of life on the earth is much less than any of

fcfer

' ,i.t'

!!i|i|!!Jlllllil!l!'i;:

•giryw

ivtfrVia'Bii

The Tokio Seismologicai Observatory.

earth, we must remember that the earth's atmosphere
may have been very different in the past ; the earth may
have been very greatly blanketed, and the surface may
have been actually warmer, although there was much
less solar radiation. That the atmosphere is far more
important in this connection than the amount of solar
radiation, is evident if we consider Langley's determina-
tion that in the tropics, if there were no atmosphere, the
temperature of the surface of the earth would be - 200' C.
Any addition to the quantity of air in our present atmo-
sphere means an increase of the temperature of the rocky
surface. But in the past, not only may there have been
more atmosphere, but there may have been a very dif-
ferent kind of atmosphere. Again, we must consider a
possible great amelioration of climate due to the earth's
internal heat. It could not occur by mere conduction,
but it is quite possible that for many millions of years
there was great blanketing by clouds of watery vapour,
and that underneath these blankets half the surface of
the globe may have been a lake, or a number of lakes, of
melted lava, which may have carried large amounts of

NO. 1329, VOL. 51]

the above estimates ; but if the palaeontologists have
good reasons for demanding much greater times, I see
nothing from the physicist's point of view which denies
them four times the greatest of these estimates.

John Perry.

THE SEISMOLOGICAL OBSERVATORY
DESTROYED AT TOKIO.

THE destruction by fire of the Seismologicai Observa-
tory and Library, at Tokio, Japan, has already
been referred to in these columns (p. 533). The valuable
work which Prof. Milne has accomplished during his
long stay in Japan is well known to our readers ; and it
is to be hoped that means for its continuance will be fully
provided. By the kindness of Japanese friends. Prof.
Milne has been able to make observations in a temporary
home since the fire, and it will not be for lack of en-
thusiasm and activity if a new observatory is not soon in
working order. We print below extracts from Prof. Milne's

536

NA rURE

[April i8, 1895

optimistic account of the fire, and accompany it with a
view of the Observatory buildings and house.

"It came at last. On Sunday morning, the 17th
February-, at 7.30 a.m., I was alarmed by the cry of fire,
and at S o clock I was looking at smoking ruins in
the midst of my two armsful of salvage (which I took
good care should include my last year's photographic re-
cords), receiving cards of condolence fromhigh personages
and presents from the neighbouring shop-keepers — like
bottles of beer, bo.xes of eggs, and oranges — and all this
while the fire engines were vigorously pumping. 1 saw
that nothing more was to be saved, but before the flames
were out, my colleague, Mr. C. D. West, set to work to
take a series of snap-shots with his hand-camera. The
results look like fogged plates, but they show amongst
other things the effects of heat upon my big stone column.
On Tuesday, I used some of the pieces as illustrations to
a geological class as illustrative of the action of lava
streams upon rocks they occasionally flow over. The
President of the University, who very kindly had hurried
from his house to see me and my ruins, had a new house
ready for me before my own had done smoking, and I am
now in it arranging furniture I have hired, sorting through
heaps of charred paper, and getting ready to set up two
new pendulums. These latter, if they work well, I hope
to bring with their records to England, to show as a type
of instrument which may be able to record movements
which go round the globe and possibly through its
interior. When earthquakes are recorded throughout
Great Britain, it will not be necessary to always intro-
duce a conversation with remarks about the weather.

" .\s nearly all the Transactions of the Seismological
Society were packed up to go to Europe, a few that had
middle places in the boxes may be saved, but I doubt if
even out of 2500 copies I shall get more than two or
three hundred. All my old earthquake books, some of
which even dated from 1500 and 1600, but which were
perhaps more curious than useful, seem to have gone.

" Instruments were fused or vapourised. Sixteen
specially constructed clocks, which would turn drums
once a day, once a week, or drive a band of paper for two
years, together with seismographs and horizontal pendu-
lums, self-recording thermometers and barometers, micro-
scopes, and a museum of old and new contrivances, are
now on the scrap heap. Until to-day, I felt that I had
the observatory I intended to put up in England
completely furnished, and 1 was proud of the furniture.

" The fire broke out in the midst of a pile of wood in
an out-house, and this with a nice wind blowing on a
Sunday morning when there was no one near to help.

"And now I have next to nothing — decorations,
medals, diplomas, clothes, manuscripts, extending over
twenty-five years, and everything else has gone to smoke ;
still it is not altogether a misfortune.

" Looked at in the right way, like an earthquake, a fire
may after all be a blessing in disguise ; but, of course, it
is sometimes pretty well wrapped up.

" Dies irae, dies ilia,
Solvel saeclum in favllla."

" This letter arrived exactly the very day one of my
pupils, Mr. Langlett, tried to get the gas of Cleveite in
my laboratory. The gas given off from my mineral did
not contain a trace of argon. The spectrum has been
examined by Tbalon, who found an exact coincidence of
the line of the gas with the helium line and besides some
others : —

TEURES TRIA L HELIUM ?

T HAVE received the following letter and enclosure
■'■ from Prof. Thorpe :—

" University of Glasgow, April 16.
" My dear Lockver,— The enclosed extract from a
letter just received from Cleve of Upsala may be of in-
terest to you. '' Ever yours,

"T. E. Thorpe."

Wave-length.
6677

5875-9

5048

5016

4922

47135

Intensity.

half-suong

strong : helium

half-strong

strong

half-strong

weaker

" I have got from Mr. Crookes a letter in which he
informs me that the gas in Cleveite contains the long-
searched for helium.

NO. 1329. VOL. 51]

" I have sent a letter about it to Berthelot. If you like,
you may communicate the result to the Chemical
Society, Mr. Ramsay, Crookes, and other friends. . . .
An experiment to determine the specific gravity did not
give trustworthy results, but seems to indicate that it is
a very light gas, still more heavy than hydrogen. Will
this gas fill the gap between hydrogen and lithium ? It
will become very interesting to see. What makes me
much curious is that our helium gas was free from argon,
and that Mr. Ramsay's (according to Comptcs rendus)
did contain that curious stufi". Is there any relation
between argon and helium, and are we facing a new
epoch in chemistry?"

Although my results are not yet complete for publica-
tion, the foregoing communication makes it desirable that
I should state at once that immediately on the publication
of Prof Ramsay's statement, by the kindness of Mr. L.
Fletcher I was enabled to study the gases given ofil' by
Cle\eite by heatirg in vacuo, a method 1 have used for
metals and meteorites.

A very small quantity of Cleveite is all that is necessary
to obtain a considerable volume of the new gas, which
comes off associated with hydrogen.

1 have now examined several tubes. I have found no
argon lines ; I have not found the lines, other than the
yellowone,given by Crookes ; but lines have been recorded
near some of the wave-lengths given by Thalcn, especially
the one at 6677, near a line I discoveicd in the chromo-
sphere in 1F68. So far the sky has not been clear
enough to enable me to determine by direct comparison
with the ihromospheie the position of the line in the
yellow with great dispersion.

J. Norman Lockyer.

NOTES.

In honour of M. lierthelot, and as a demonstration of the
power and progress of science in France, a banquet was held it
Paris a few days ago. Nearly eight hundred guests were
present, among them being M. lirisson, President of the
Chamber of Deputies, and M. Poincare, Minister of Public
Instiuclion. Upon the invitation cards were printed the
words: " Ilommage a la science, source de raffranchissement
de la peni-ce." M. Poincarc made an eloquent speech in praise
of the work done by the eminent Secretary of the Paris
Academy of Sciences, and M. lierthelot, in his reply, dwelt, at
some length, upon the beneficial influence of science on social
and moral, as well as material, progress. Science, he said,
had for its only guide the love of truth, and confidence in il-
final triumph. Proved under all circumstances, and strengthened
every day by success, the scientific method had become the
principal .source of the moral and material progress of society.
In fact, science was the source of all progress accomplished
by the human race. Kvery one knew that, during this century

April i8, 1895

NATURE

587

scier.ce had conferred great benefits upon civilised peoples by
the application of its results and laws to mechanical, chemical,
and electrical industries. But M. Berthelot held that material
progress was the least of the fruits of scientific work ; he claimed
for science the more extensive domains of the moral and social
world, and vindicated the position taken up by him in bis article
on " Science et la Morale," which appeared in the Rntie de
Paris. The speech and the banquet may be taken as an effec-
tual reply to those who question the benefits of scientific
investigation in France.

O^LV last w<ek, in announcing the publication of the fourth
edition of Prof. James D. Dana's "Manual of Geology," we
referred to the exiiaoidinary activity of ihe author. We regret
this week to have lo lecoid his c'eatb, at eighty-three years of
age. Another eminent man of science who has just passed
away is Prof. Lothar von Meyer, at the age of sixty-five.

Reu ter's correspondent at Toronto reports that the Provin-
cial Legislative -Assembly of Ontario has authorised a grant of
75CO dollars towards defraying the expenses of a meeting of the
British Association for the Advancement of Science to be held in
Toronto in 1897, should the Association accept the invitation to
hold a meeting there.

Mr. R. Fitch, whose name is especially well known among
aichseologisls and geologists of Norfolk and Norwich, and
who, three ytais ?go, presented his collections to the Norwich
Muitim, ai:d provided cases for them, has just died, at the
advanced age of ninety-three.

John Adams Rydeb, Professor of Embryology at the
University of Pennsylvania, died on March 26.

Prof. James E. Oliver, the mathematician, who was
ccnnccted with ^he Cornell University faculty for twenty-five
years, died at Ithaca, on March 27. He was born in Port-
land, Me., July 27, :829. He graduated at Harvard in 1849,
and received in the same year the appointment of assistant
editor in the office of the American Nautical Almanac. He
became in 1S71 assistant professor of mat hematics at Cornell
University, and in 1S73 *^5 appointed to the chair as Professor.
He was a member of the American Academy of Arts and
Sciences, the' American Philosophical Society, and the National
Academy of Sciences.

A monu.ment to the late Prof. Villemin, who added so much
to ihe knowledge of the nature of tuberculosis, has just been un-
veiled at Val c!eGiace. A monumental souvenir of the late
Prof. G. Pcuchet «as aho unveiled a few days ago, at Pere-
Lachaise.

The Heme .^ocielaiy, en the application of Ihe East Riding
Courty Council, has made an order prohibiting the taking or
destroying of wild birds' eggs on the promontory of Spurn
for a peiiod of five years. Spurn Point is one of the chief
places of deposit by sea birds of their eggs on the Yorkshire
coast, and of late years there has teen w.inton destruction of
both sea-gulls and their eggs.

A cORREsroNDENT infoims us that a very bright meteor was
seen at Ta)port, N.B., at lob. 4m. p.m., on Saturday, April
13. It started at a point a little to the east of Vega, and was
moving almost directly towards Saturn. It was visible for about
six seconds, and seemed to have a jerky motion. It was more
brilliant than Venus, and w.-vs elongated in shape. The
weather was veiy clear and quiet at the lime of observation.
The meteor's direction of flight was, approximately, from 270"
+ 40" to 221° - f.

NO. 1329, VOL. 51]

Sir Joseph Fayrer, Sir Guyer Hunter, and Mr. Jonathan
Hutchinson, the adjudicators, have (says the Brilisk MiJical
Journal) awarded a prize of fifty guineas to each of the follow-
i rg essays, sent in in response to the invitation of the Leprosy
Fund : " On the history of the decline and final extinction of
leprosy as an endemic disease in the British Islands," by Dr.
George Newman ; " On the conditions underwhich leprosy has
declined in Iceland and on the extent of its former and present
prevalence," Dr. Edward Ehlers (Copenhagen) ; " On the facts
as to Ihe recent increase of leprosy at the Cape and its present
prevalence in South Africa," Dr. S. P. Impey (Medical Superin-
tendent, Robbin Island) ; " On the reputed recent increase of
leprosy on the Australian Continent ; its extent and possible
causes," Dr. Ashburton Thompson ; " On the conditions under
which leprosy prevails in China, Cochin China, Batavia, and
the Malay Peninsula," Dr. James Cantlie (Hong Kong). On
some of ihe subjects for which prizes were offered no essays
were sent in, and some of the essays sent in were held
not to meet the terms of the competition. The successful
essays will be printed and published at the expense of the
Fund.

Aboit 1 1. 15 on Sunday night, shocks of earthquake of vary-
ing intensity were felt over a considerable portion of Austria-
Hu ngary, extending from Vienna to the Adriatic coast and the
adjoining islands in one direction, and from Sahbui^ to Agram
in another. In Vienna, according to the limes correspondent,
the shocks were slight. Clocks were stopped, however, in
parts of the town, and windows were heard to rattle. The
vibrati ons are reported to have proceeded from south to north.
The earthquake would seem to have reached its greatest in-
tensity within a triangle formed by Laibach, Trieste, and Fiume.
At Laibach no fewer th.in twenty-five shocks were noticed,
and they continued until seven o'clock on Monday morning.
The collections in the Laibach Museum are said to have been
almost entirely destroyed. At Trieste several vibrations were
felt, one of which was often seconds duration. Many buildings
have heen more or less damaged. Tremors of still longer
dur alion are reported from Krainbui^. Shocks of less violence
o ccurred at Klagenfurt, Leibnitz, Luttenberg, Agram, and else-
where. Four distinct vibrations were felt at Venice : the first,
which took place at 11. 17 p.m., was very severe, and lasted
twelve seconds. Severe shocks of earthquake were also felt in
Italy, at Ferrara, Udine, Treviso, and Padua.

We have on various occasions given short descriptions in these
pages of experiments carried on by different investigators with a
view to discovering a practicable method of telegraphing over a
considerable distance without metallic wires connecting the two
stations. Among the observers who have devoted a considerable
time to this problem may be mentioned Mr. Preece, the chief
engineer of the Telegraph Department of the Post OfiBce ; and
it is to this gentleman we owe the first practical application of
the method of telegraphing by induction. During last week the
submarine cable connecting Oban with .\uchnacraig broke
down, and the telegraphic messages have since been passed be-
tween these two places (distant about six miles) by means of
Mr. Preece's inductive method. .\ gutta-percha insulated wire,
one and a half miles long, was laid along the ground from
Morven, whilst on the Island of Mull use was made of the ordin-
ary overhead line connecting Craignure with Aros. The dis-
tance between the two parallel wires was about 3|i miles, the
Sound of Mull being here at its narrowest. Using a vibrator
as transmitter, and a telephone as receiver, the u;ual messages
were successfully dealt with until the cable was repaired, the
whole experiment forming a very interesting event in the annals
of telegraphy.

588

NA TURE

[April i8, 1895

A PAPER which will have considerable interest for those who
have to design and use electrical apparatus, where wood or
slate is often used as the insulator, appears in the Pro-
cudings of the American Academy. The subject of the paper
is the electrical resistance of certain poor conductors, such as
wood and stone, and is by Mr. B. O. Peirce. The author has
examined a great number of samples of different kinds of woods
and stones under different conditions as to dryness, a most im-
portant point, and although, as might be expected, the individual
results differ somewhat widely, he considers the mean results
give a very fair idea of what may be expected in practice. The
author has also tried the effect of soaking the different materials
in hot melted paraffin, and finds in every case, especially if the
specimen has been previously well dried, that such treatment
not only increases the specific resistance, but by preventing the
absorption of moisture prevents the falling off in the reiistan ce
otherwise observed when such bodies as stone or wo^d are ex -
posed in a damp place. The following are some of the resu Its
for the specific resistance obtained in megohms ; the first num -
ber denotes in each case the lowest value observed, and .|the
second number the mean value -.—Mahogany 310, 610; hard
pine 17, 1050; white pine 360, 1470; vulcanised fibre 3, 60 ;
slate 184, 280 ; white marble 2000, 8S00. The samples of
wood were all well seasoned, and the resistance was measured
in the direction of the grain, the resistance across the grain
being generally from 20 to 50 per cent, higher. The samples
of stone were dried in the sun for about three weeks before
being tested.

A SIMPLIFIED phonograph is described by A. Koltzow in the
Centralztitung fiir Oplik iind Mechanik. A conical tracing
point is used for recording the sound waves. This has the
advantage of durability, and if it should wear out on one side ,
it need only be ;tumed round its axis. The tracing-point is
attached to one arm of a lever, the second and longer arm being
provided with a membrane. For some purposes the membrane
is replaced by a stretched string. The cylinders consist of a
very hard soap. They will stand several hundred renderings.
Alter use they can be turned down by 002 mm., so that one
cylinder will suffice for 200,000 words.

In the Comptes rendus of the Paris Academy of Sciences of the
1st inst., as briefly stated in our abstract last week(p.576). Prof.
Mascart presented a note by the Abbe Maze, stating that in a
collection of astronomical documents at the National Observa-
tory, a register had been foimd containing thermometrical and
other observations made by the astronomer I. BouUiau, between
25 May, 1658, and 19 September, 1660. Up to the present
time, it was not known that observations hid been male at
Paris prior to those of Lahirc. These observations are of some
interest, being among the earliest thermometrical readings on
the continent, and they fill up a gap in the climatological
history of Paris. It is also noteworthy that the thermometer
used was one of the Academy del Cimento.

A RKCENT number of Modern Medicine and Bacteriological
Rrji€W contains a notice of Dr. Pictet's interesting experiments
on the application of intense cold as a therapeutic measure.
According to this investigator's observations, calorific radiations
of a lower temperature than - 65° pass through all the ordinary
conductors of heat ; a fur overcoat or a wooden board offering
no more resistance than a pane of glass or other transparent
medium to the passage of a sunbeam. Dr. Pictet experimented
upon himself in a frigorific well, in which a temperature of
- 100' C. to no' C. was maintained. He was wrapped in
warm clothes and thick furs, and at the end of four minutes
he stated that he experienced intense hunger, which in-
crcaMd ; after eight applications of eight or ten minutes

NO. 1329, VOL. 51]

duration his appetite became normal, and his digestion greatly
improved.

The last number of lhe£o//etino of the Italian Geographical
Society criticises the proposed nomenclature of some of the
rivers of East Africa, as given in a sketch map in the Geo-
graphical youmal illustrating the explorations of the American
traveller. Dr. Donaldson Smith. The names to which the
Italian Society objects are those of Dr. Smith himself and of
his English companion, Mr. Gillett, which have been applied
to the upper and middle course of the Webi Shebeli and the
Web respectively. We are bound to admit that the criticism
is well-founded, as it is contrary to authorised usage to apply
European names when the native names can be ascertained.
We have little doubt that Dr. Smith will, before the end of his
explorations, discover some features still unknown which may
fitly be called after him and perpetuate the memory of his ex-
cellent geographical work.

Mr. H. Rutgers Marshall, whose work on "Pain,
Pleasure, and -Esthetics" was reviewed in Nature (vol. 1. p. 3),
contributes to the April number o( Mind An article, " Emotions
versus Pleasure-Pain," in further elucidation ot his views. Mr.
Marshall is fully alive to the importance of evolutionary de-
velopment, and his treatment of the emotions is therefore of
interest to students of comparative psychology. It is unfortu-
nate, however, that the term "instinct " is used in an extended
sense which will scarcely be acceptable to those who approach
the subject from the biological side. The phrases, " imitation
impulse," "art impulse," " benevolent impulse," would appeal
to them as more satisfactory than "imitation instinct," "art
nstinct," &c., since they have grown accustomed to the appli-
cation of the term instinct to the manifestation of particular
activities. But a consensus of opinion on psychological nomen-
clature seems at present impossible. .\nd in any case, Mr.
Marshall's views are well worthy of careful co nsideration.

An experiment of considerable interest in connection with
the transmission of optical signals has been performed by
M. Charles Henry at the Depot des Phares. The question
was whether rhythm in a succession of signals increases or
diminishes their visibility ? This was solved by means of a
revolving drum, the surface of which contained sixty holes
illuminated by a source of light placed at the axle. The drum
was 3 feet across, and was driven by clockwork. By varying
the speed of the drum and the brightness of the light, and by
closing some of the holes at regular or irregular intervals, all
the conditions of the experiment could be varied at pleasure.
The chief difficulty in this, as in most physiological experi-
ments, lay in bringing the eye back to its original state .ifter
each experiment. It was sometimes found impossible, even
after keeping in the dark for close upon half an hour, to restore
the observer's eye to its original state of sensibility. But it was
conclusively shown that it is possible to increase the range
through which an optical signal will carry by arranging the
succession of flashes according to a sufficiently complex non-
rhythmical law.

PROiiAbLY no better example of an invention borrowed or
adapted from nature could be found than is afforded by llie
sand-blast. As is well known, the invention, now a quarter o(
a century old, consists of a stream of sand or other abrasive
powder, usually dry, but sometimes mixed with water, projected
with more or less force and velocity to strike and pulverise the
surfaces of glass, stone, metal, and other materials upon which
it is directed. The many applications of this method of
abrasion were recently described by Mr. J. J. Holtiapffel, at
the Society of Arts. It appears that glass is almost immedi-

April i 8, 1895 J

NA TURE

589

ately depolished by the blasts now in use, and but a compara-
tively short time is required to pierce and cut apertures through
sheet and plate glass. Stone, marble, sla'.e, and granite are
just as amenable to the action of the sand-blast. Iron, steel,
and other metals have their surfaces easily reduced, and
smoothly or coarsely granulatel, according to the force and
abrasive powder used. It is remarkable that it is by no means
necessary that the abrasive be harder than the material to
which it is applied ; thus, hardened steel and corundum are
readily pierced with sand. The blast is not only in use for
producing a urjform granulation on sheet glass ; it is also em -
ployed for frQSting the babbles of iacandiscent lamp, and the
like ; for the decoration of glass ware, and the labelling of
graduated measi'es. In metal, the hird scale, so destructive to
cutting tools, is removed from castings and forging; by the
blast. On stone, slate, and granite the sand-blast is used for
incised carving an! inscriptions in intaglio or relief, and for deli-
cate drawing for lithography. A print of a child's head, exhibited
by Mr. Holtzapffel, was an astoniihing example of the delicacy
of treatment obtainable by the process. Among other purposes,
the blast is employed for removing fur and deposits in
tubes and tanks; foi cleaning off accumulations of paint and
dirt within iron ships . for decorating coat and other buttons ;
for piercing the aperures in glass ventilators ; for marking
pottery, and in the mmufacture of ornamental tiles ; for re-
facing grindstones, emtry, and corunlum wheels ; for granu-
lating celluloid films for photography ; and on wood, to bring
out the grain in relief, and, latterly, for blocks for printing.
These many and various applications of sand-blast processes
show that the art has developed in an extraordinary manner
since it was introduced by Ir. Tilghmann in 1S70.

Dr. H. Wild has puJishei, in the Zapiski of the St.
Petersburg Academy of Scietces, a very impo.'tant investiga tion,
entitled "New Normal Ar-Temperaturei for the Russian
Empire." In a former paps: upon this subject, the data for
the monthly, yearly, and fivi-;parly means were brojght dow n
to the year 1875, while in theoresent work observations ha ve
been included to the year iSgo.md comprise materials from no
less than 575 station;, of which 44 are n;w.

The additions to the Zoologies Society's Gardens during the
past week include an Irish Stoa (Putorius hibernicus) from
Ireland, presented by Viscoant bwerscourt ; a Grey "arrot
(Psillacus erilhactis) from West Afr;a, presented by Mr. A. A.
Dowty; a Cape Viper {Caiisits rhotJjiatus) from South ;Africa,
presented by Mr. J. E. Matcham ; ho Elephantine Tortoises
(lestuJo eUphantina) from the Aldbra Islands, Seychelles ;
four Indian Pythons {Python moltirui from India, .deposited ;
a Barbary Wild Sieep (Ovis traglaphus), born in the
Gardens.
. \

OUR ASTRONOMICAL \OLUMN.

Lunar River Beds and Variable pots.— The highly
favourable atmospheric conditions at Artuipa have enabled
Prof. W. H. Pickering to make numerous,bservations which
have a special bearing on the question of th<existence of water
on the moon (Annals Han'ard College Ohenatory, vol. xxxii.
part l). In addition to the ordinary rills, P.f. Pickering has
catalogued thirty-five narrower ones, which, f.in their resemb-
lance to terrestrial watercourses, he does not «sitate to regard
as "river beds." These are wider at one id than at the
other, and the wide end always terminates iia pear-shaped
craterlet. Most of them are only a few miles ijength, and a
few hundred feet in width at the widest part, am except when
very deep, they are very difficult objects. Th largest and
most readily observed has its origin in the Mount'adley range
n the Apennines ; its course lies a little north of est, and its
otal length is about sixty-five miles. There does n appear to

NO. 1329, VOL. 51]

be any reason to suppose that these formations actually contain
water at the present time, but Prof. Pickering brings forward
other evidence in favour of the presence of a small amount of
moisture on the lunar surface.

Certain variable dark spots have been detected in different
regions, many of them lying inside craters, others symmetrically
surrounding craterlets, and others in the dark marja, or "seas."
In the central craters, such as Alphonsus, the spots are darkest
just after full moon, when shadows are geometrically impossible,
and they are invisible when the shadows are stronge>t. "If
called upon to offer an explanation of the phenomenon, we
seem forced to call in the aid of water as an active agent."
Still, the dark spots cannot be simply ponds, as one of the
spots in Alphonsus for a portion of the time covers and darkens
the slopes of a small hill near the crater-wall. " This seems
to effectually overthrow the hypothesis of a free liquid surface,
as well as the suggestion that the dark colouration may be due
to frozen ground that has partially thawed. . . . Vegetation
would undoubtedly explain away all our difficulties ; but before
we resort to such an extremily, it is evident that we need more
facts upon which to base our theories."

The Mare Tranquilitatis is said to be almost covered by these
variable spots, and Prof. Pickering stales that the changes may
be seen with the smallest telescope, or even with the naked
eye ; until past first quarter this area is lighter than the Mare

; Crisium ; it then rapidly becomes the darker of the two until

i after full moon, when it again becomes lighter.

> The changes in some of the spots are readily seen in the
beautiful photographs which illustrate the memoir.

The Ultka-Violet Spectrum of the Corona.— With
spectroscopes in which the optical parts are made ol glass, it is
only possible to photograph the spectrum in the ultra-violet as
far as wave-length 360 ; but when the spectroscopic train con-
sists of quartz and Iceland spar, a more refrangible region is
open to investigation. One of the spectroscopes employed in
Africa by M. Deslandres during the I 'al eclipse of the sun on
April 16, 1893, was of the latter form, and a plate exposed for
four minutes gives for the first time some information as to the
coronal spectrum in tlie extreme ultra-violet (Cf/«//« rendus,
April l). The slit of the spectroscope cut the image of the
corona along the equatorial diameter, and to facilitate the reduc-
tion of wave-lengths, the spark-spectrum of iron was photo-
graphed on the same plate. The photograph shows the spec-
trum of the corona to consist of bright lines superposed on a
continuous spectnim. In the blue, the continuous spectrum
reaches a height equal to two-thirds the sun's diameter, but it
diminishes both in height and intensity until about A 300 it is
almost reduced to zero. Forty lines are tabulated from \ 308
to A 362 ; one at A 31709 appears to reach a great height in
the solar atmosphere, and others at A 3164-5, 3189-5, and
3237-1, are comparable with the hydrogen lines Hj, H,, and
Hj. The remaining lines may belong either to the chromo-
sphere or corona ; but M. Deslandres considers the fact that they
are shown with a small image on the slit, to be in favour of
the view that they are coronal. Most of the lines cannot be
identified with known substances, and they probably represent
gases of low atomic weight.

Stellar Parallaxes.— A very suggestive investigation of
stellar parallaxes in relation to magnitudes and proper motions,
has been carried out by Mr. T. Lewis (Observatory, April).
The parallaxes adopted are the means of the values obtained
by various observers, and from these the velocities across the
line of sight have been derived by dividing the proper motions
by the parallaxes and reducing to miles per second. The con-
clusions suggested by the tables given are : " U) Leaving out a
few of the brightest stars, the parallaxes are constant down to
2-7 magnitude. (2) After 27 mag. is reached, the parallaxes
are doubled and remain practically constant to 8 4 mag. (3) Up
to the 3rd mag. the velocities are very small, averaging
about 9 miles per second, while after the 3rd mag. the velocity
is 38 miles per second." It seems probable that in our
immediate neighbourhood there are a few stars of exceptional
brilliancy (about 8) and a few smaller stars, of which nearly 40
are at present known ; while stars of mag. I to 3 are as a class
far outside this inner space, and have very small velocities.
The investigation confirms the accepted idea that a measurable
parallax accompanies a large proper motion, and shows, further,
that this holds good whatever the magnitude of the star
may be.

5QO

NA TURE

[April iS, 1895

THE SUN'S PLACE IN NATURE}

IV.

THE difference in the appearance of spectral lines and
flutings having been explained, I now go on to state that
the luminosity referred to, as seen in the meteorite experiment
was not one of the lines in the spectrum of magnesium, but one of
the flutings. I will next throw this on the screen (Fig. 17), and
you will at once see the point. Here is the spectrum of magnesium
obtained at the lowest temperature at which we can get any light
from it at all. We have a fluting, which resembles closely the
carbon fluting, but in a different part of the spectrum. We see
that its brightest part is coincident with a certain part of the
solar spectrum : and it so happens that the position of the line
which l>r. Huggins had observed in the nebula; lies very near
the same position of the solar spectrum.

That, then, was one argument out of a great numberjin favour
of the view that the luminosity to which the bright line of the
nebula was due, might really be produced in the nebulx by
collisions of meteorites among themselves, rendering luminous
the vapours of magnesium which we knew to be wherever there
are meteorites.

Now, an additional argument for that view was found in the
fact that almost every observer, including Dr. Huggins himself,
bad stated that as seen in the spectrum of a nebula the line did
look somewhat difTerent on one side to what it did on the other,
and references were made to its being more degraded on the
left-hand side than it was on the right. I h.-id frequently

light from the nebula of Orion on a powerful horizontal
telescope placed in front of a large spectroscope, both rigidly
fixed. In order to check the observations as far as possible, I
placed in front of the object-glass of the telescope an arrange-
ment by which the light from a magnesium wire might enter the
slit of the spectroscope at the same lime as the light of the
nebula, so that if the light from the nebula and the light from
the magnesium wire perfectly agreed in wave-length, we should
get one line ; if it differed, we should get two.

The slit of this spectroscope was exactly in the focus of the
ten-inch object-glass, and then the light was passed through
four dense prisms, so that we got a consideraole amount of
dispersion, and the exact position of the line, whether single or
double, was observed. That of course wcs a very much
more powerful dispersion than had been employed by Dr.
Huggins in his first observations, and muc'i more powerful
than had been employed by myself in my frst investigation.
But what I wished to do in those first investigations w.-is to
understand and to clearly follow the observations which had been
made previously by others : if therefore I hid attempted to go
over the ground «ith instruments ten times better, giving me
ten times finer results than my predecessors had obtained, it
would have been the worst possible way togo to work, because
it was essential for me to make the necessiry comparisons with
the old observations while not exceeding tie instrumental means
which had been employed to obtain then.

The long and short of my various nethods of observation
was that they seemed entirely to confirn the idea which I got
in the first instance from using telescipes and spectroscopes
of very much smaller power. That, lowever, fortunately, for

Fig. 17. — Spectra of bumine ni.igne^iiim compared with solar spectrum.
(1) Sun. (?) Magnesium.

observed myself that the line representing the chief line of the
nebulx was degraded to the left, never to the right, over parts
of the nebula of Orion which were more brilliant than the others ;
and at the same time that another line — about which more
presently — instead of being degi.ided to Ihe left, like this one,
was equally eased oflT on both sides (Kig. 18), so that the argument
was complete that the appearances presented by this line
were not due to any instrumental defect, because, in that case,
all the lines would have behaved in the same abnormal manner.
Hence then I found myself justified in concluding and sub-
sequently stating (I; that the position of the meteoritic dust-
line was coincident with the line of the nebulae in the apparatus
which I used, and (2) that it resembled it in appearance.

What I had next to do in the matter was, of course, to carry
the thing as far towards the truth as I could. We can never
find out the whol^ truth, but it is better to have a part of the
truth than none at all. Hence I started a new method of
attack, which, you will note, differs very considerably from any-
thing you have seen before. I have here a beautiful instrument
invented by that eminent I'rcnchman Foucault, called a "sidcro-
Stat." The essential part is a plane mirror (Fig. 19) which, when it
i» properly adjusted to the sun or moon or any star in any part
of the sky, lays hold of a beam of light from it about twelve
inchei in diameter, and sends that beam in a horizontal direction
due south, and keeps it there ; so that the light falls fairly on
the optical apparatus, and we can go on observing it for a
i,,n.. i.,„. Next the instrument was adjusted to throw the

n shorthand nolc«ofa course of Lecture.^ to Working Men

- of Practical Geology durinK November and December,

Tov<- t'-ontinucd from pAce 567.)

NO. 1329, VOL. .si]

I'iG. 1^. — .\ppearance of principal'J'ics in spectrum of Orion nebula, as
observed afVestgatc-on-Sea.

science, did not satisfy Dr.Iuggins; hevery wisely appealed to
the .-\merican astronomei, and I am glad to say that the
skilful astronomers of theLick Observatory took up this work
with interest, and emplred instruments in the investigation
more powerful than an- 1 possessed, thus carrying matters a
stage further. There wre leally two distinct bits of work to
be done ; first of all, ne wanted the exact position of the
line in the nebula;, ani after having got its right position, its
origin could be thougl out. We wanted also to see what the
real physical appeara^e of the line was, i.e. whether it was
most likely a line or fluting. It is not a little curious to
note that all the sla nients which had been made suggesting a
fluted character of "c line were at once withdrawn when I
referred its origin t 'he magnesium fluting.

The Lick telesc'C 's one of very considerable power indeed,
and it is so solidly'U'jt that a very powerful spectroscope can
be put on one en of 't and used under almost the best possible
conditions for t^ermining the position of lines. .Still the
Lick telescope not Ihe best possible telescope to employ for
any branch of\«'k connected with nebula;, if thewotk requires
a great amour of light, because the longer the Iclcscope,
the larger the "gc which the object-glass gives ; for instance,
if you are dfipg «'lh a nebula one degree in diameter, if
yoiir one degeis written on a circle with a radius of sixty feet,
it will be a efy much bigger thing than if on a r.idius of
ten feet, scyo" RCt a large image without increasing the
light, and erefoie arc spieading your light over a very large
area. As^e slit of the spcclroscope is a very small thing,
all the li'' «hich is thrown outside Ihe slit is of no use for
your spcfoscopic obscrvalicn, so, whatever the size of the
spectres pe may tc, you want to deal with the smallest and

April i8, 1895]

NATURE

591

brightest possible image in order to get the best use out of
■your spectroscope, and ihat cannot be done with a long focus
telescope. However, the important question for the American
observers was to determine the exact position of the line ;
and we have lately been given some very interesting results.

Fig. 20 represents the way in which Dr. Keeler puts
his last result. The upper part is a representation of the solar
spectrum ; the numbers represent wave-lengths on Rowland's
scale. According to his latest value the wave-length of the
nebular line 155007-05. He also shows in relation to it the lines
of nitrogen as well as the fluting of magnesium, and you see at
once that, although according to this drawing the magnesium
does not quite correspond with the line of the nebul.t, it is
very much nearer to it than is either the line of lead or
the lines of nitrogen. The publication of this result
necessitated a fresh investigation, to see what the exact
facts were when we no longer compared the nebula with
magnesium, but compared the magnesium with the' solar
spectrum, and therefore sought the true position in which
to place the magnesium line in relation to the solar spec-
trum.

Here is the result. Vou will see that there is a very small
dflference between the position of the magnesium fluting and
he nebular line. In short, the more the work done on this

■ Fig. 19. — Showing object-glass ofyiorizontal telescope used with siderostat

question 'the more and more coincident have these lines be-
come, and there are some iconsiderations which have not yet
been taken into account.

I have referred to this point somewhat at length, although
the coincidence with the fluting of magnesium is not funda-
mental for the establishment of the view which even Dr.
Huggins has now accepted, in the way I have already
Stated.

Now, what was the chemical constitution of the nebula stated
to be as a result of the first spectroscopic observations ? Dr.
Huggins, in his paper of 1865, to which I have already
referred, was of opinion that the chief line was due to
nitrogen.

Here are two tubes, one containing hydrogen, the other
nitrogen. You will see at once that these two gases, when I
set them glowing by the passage of an electric current, are very
different in colour ; we get in one an excess of red light, in the
other we have a purple tinge. When nitrogen is observed by
means of a spectroscope, a double line is seen very nearly
coincident with the line of the nebul.x-. Dr. Huggins thought
that one of the constituent lines was exactly coincident with it,
and because there was apparently no line whatever correspond-
ing with the other, he thought also that the nitrogen might not be

NO. 1329, VOL. 51]

nitrogen like that with which we are familiar, but an unknow^a
form of it. There was no doubt from the beginning that
another line was a line of hydrogen, although there was some
slight doubt as to whether the hydrogen in the nebulae behaved
exactly like hydrogen on the earth.

Nobody believes in the nitrogen constituent of the nebulae
now; and I presume Dr. Huggins has withdrawn in fact, if
not in words, his statement concerning the coincidence,
for in his address as President of the British Associa-
tion, in which, as I have already stated, he withdrew his pub-
lished statement as to the position of the nebulx a-nong the
various bodies that people space, he remarks, "the progress of
science has been greatly retarded by resting important conclu-
sions upon the apparent coincidence of single lines in spectro-
scopes of very small resolving power," an apolo^a of which
every one will see the propriety, for you will gather from Dr.
Keeler's diagram that the nearest nitrogen line is three limes
further removed from his position of the nebula line than is the
magnesium fluting. I trust I shall not be thought to be
exceeding the bounds of decorous criticism when I remark that
while Dr. Huggins has referred to the inaccuracy of my
work in relation to this line, which is apparently indicated by
Dr. Keeler's results, he has never pointed out the three times
greater inaccuracy of his own.

In order to give you an idea of the
relative accuracy which all these refer-
ences to wavelength indicate, let us sup-
pose that we are trying to define the
position of a place in London on an E.
and W. line running through Charing
Cross, and then you will see exactly how
matters stand. Assuming Dr. Keeler's
value to be absolutely true — and I expect
it is as near the truth as we are likely to
get for some lime — we will suppose that
it represents the nebular line situated on
the statue of King Charles at Charing
Cross. When Mr. Huggins first raea-
.sured it, he brought it to the East India
Docks ; his next attempt brought it to
Hammersmith. Dr. Keeler's first obser-
vation brought it to .\lbert Gate ; his
next, in 1891, brought it to S:. James's
Palace. Subsequent work at Kensington,
not yet completed, has brought it nearer
still.

There is another argument in favour of
the now accepted view which may be
gathered from a careful examination of the
forms of these different nebulas, and by
endeavouring to reason out from the form
what the actual conditions at work may be.
One of the most wonderful spiral nebulae
in the heavens is that in the constel-
lation of Canes Vanatici, which has
been photographed by Dr. Roberts
(Fig. 7, p. 397). This is a nebula which
we look down upon ; we see it in plan ; we are, so to speak, at
the pole of the system, so that it is not foreshortened.

There is no question about the wonderful spirals being connected
with the central condensation and stretching away from it, and
the point which I made with regard to the one in Ursa Major
is even more decided here, when I call your attention to these
points of condensation right along one of the spiral branches,
and when you get the possible intrusion of two spirals one on
the other you see a confused mass of light. Now, if we
imagine ourselves dealing there with a mass of pure gas,
whether it is hydrogen or nitrogen or ammonia — that is, a
combination of both — or any other, i; would be extremely
diflicult to see why there should be any change in tempera-
ture in diffijrent parts of that mass ; but the moment you
assume that you are dealing with cool materials — meteoritic
dust — you will see that such a picture as this is important
to u.s, for the reason not that it shows us what is there,
but because it shows us what is going on there. These
bright spots do not represent the presence of matter, and
the dark ones the absence of matter : bat these brighter
portions represent the stream lines where collision is possible
— the intervals those regions where collisions are less likely,
and you will see from the very configuration of this

592

NA TURE

[April i8, 1895

sysletn, that if all the dust, or meleorite?, or conglomerations of
particles, whatever they may be, are going the same way, there
will be a condiiion in which we shall get a minimum of col-
lisions, and therefore a minimum of temperature.

The probability, therefore, is that we are not dealing with
gas, but with masses of matter in certain regions of which, in
consequence of general action, there is greater luminosity given
off by the particles of which the nebula; are composed ; in

5000

5005

5010

Pb M-

Nebula.

ComparisoD
lines.

Fig. 20. — Vormal position of the chief nebular line, according to Keeler.

other regions where there is less action, we have lower tempera-
ture and less light.

If, as was at 6rst imagined, these nebulae are gases at
enormous temperatures, it would be a question of seeing them
or not seeing them; there would be no special parts to be
picked out at all. But, in the case of those nebula: lo which
modern photographic methods have been applied, we find that

the same scale, in which the nebula that we usually see occupies
only a very small portion ; the only difference between the
two photographs is that one has been exposed for a very long
time to enable us to fix and to study the very dim reproduction
of certain parts of it, whilst the first one was exposed only for
a short time, in order that we might dwell effectively on that
part only of the nebula which is generally visible to the human
eye with an ordinary telescope. (Fig. 2.) If we were dealing with
incandescent gas, the incandescent gas ought to leave off sud-
denly ; but all round this nebula, where th.re appears to be
nothing at all, the longer exposure brings before us other por-
tions of the nebula just as rich in details, just as exquisite in
their variety and tone as those ordin.irily seen with the naked eye.
Such a condition as that cannot be brought about by a mere
homogeneous mass of gas at high temperature, but we can explain
it quite easily by assuming that in such .i nebula as that we are
dealing with, the luminosity is brought about by disturbances,
these disturbances giving rise to collisions among the particles
which are apt to collide and give out luminosity. The nearer
they are to the centre of gravity of the swarm, the greater will
be their chance of collision, and the greater will he the lumin-
osity of their central portion.

.Still another consideration. Astronomers, since the time
of Rutherfurd, who was the first to begin stellar spectroscopic
work in the United States, between i860 and 1S70, have
established many different classes of stars as defined by the
chemical substances of which their atmospheres seem to be
composed, so far as spectioscopic observations enable us to
determine their composition. One gioup of stars is remarkable
for the presence of hydrogen in enormous quantities: we as-
sume that because the lines of hydrogen are inordinately thick.
In another we get not so much hydrogen, although it is still there,
but the predominant substance is iron. In other stars we get
little hydrogen, if any, apparently no iron, but carbon in
enormous quantities, and again there is another substance, the
quantity of which varies enormously, and that is calcium. Now,
if stars contain all these diflerent substances, and if they
represent epochs of evolution, they must be produced from
something which actually or potentially contained these sub-
stances, so that there again you get a
considerable argument iti favour of the
chemical complexity of the nebula;.

Finally, we reach the second point. It is
now generally conceded that the first stage
in the development of cosmicai bodies is
not a hot gas, but a swarm of cold meteor-
ites. From the point of view of evolution,
keeping well in touch with the laws of
iliermodynamics, the nebula; must begin
cool if they are to develop into hot stars.
J. NOK.MAN LOCKYER.
{To U continuta).

A

Fig. 31. — Orion nebula photographed with short and long expciarei

the nebula which we see ordinarily in our telescopes is only a
very, very small fraction of the real nebula as it really exists,
when we can get at it under the best possible observing condi-
tions. .Many of you, I hope, have seen the nebula of Orion in
an ordinary telescope. Mere it is as it has been photographed
by means of a telescope powerful enough to give us the brighter
portions. Here is arolher photograph ol the nebula exactly on

NO. 1329. VOL. 51]

NEW COMPOUNDS OF PHOS-
PHORUS, NITROGEN, AND
CHLORINE.
SERIES of new compounds of phos-
phorus, nitrogen, and chlorine, and
likewise a series of acids derived from
ihoni, have been discovered by Mr. H. N.
Slokes, and an account of them is con-
tributed to the American Chemical Jour-
iir.l. .\ famili.ir compound of the three
elements in question, the chlorophos-
phuret of nitrogen, discovered by Liebig
n 1832, has been the subject of frequent
study, and its nature has comparatively
riccntly been very fully demonstrated by
Dr. Gladstone. It has been shown, from
vapour density determinations, that this
remarkably stable compound, which may
be distilled in steam and boiled with
acids and alkalies without appreciable
change, possesses the molecular composition PiNjCl,,. Mr. Stokes
now shows that this substance is only one of a homologous series
of compounds having the general formula (PNCK,)n, and that
these are the chlorides of a series of acids (PNO.JIJn, which
he terms mctai)hosi>himic acids. The second member of the
series, (PNCIj)4, has been isolated from the product of Dr
Gladstone's reaction for the preparation of (PNCUlg, that be

April i8, 1895]

NA TURE

593

tween phosphorus penlachloride and ammonium chloride ; it
is a substance almost as stable a^ the triple compound, and
yields on saponification the acid (PNO.jHolj, which is likewise
a stable body. Moreover, the acid corresponding to the triple
compound has been isolated, and also a higher chloride
(PNCl2)x of an oily character, and whose molecular weight has
not yet been ascertained. In describing his repetition of Dr.
Gladstone's work, Mr. Stokes incidentally mentions the in-
teresting circumstance that the triple compound readily forms
enormous crystals, well-developed prisms several inches long
and of considerable thickness being frequently deposited from
benzene, and indeed their size appears only to be limited by
that of the containing vessel and the bulk of solution. These
crystals melt at H4°. The quadruple compound melts at I23°"5,
and boils at the normal pressure at 256' '5. It crystallises well
in colourless prisms, which are usually much smaller than those
of the triple compound, and exhibit great tendency to develop
anacicular character. It is less soluble in alcohol and benzene than
the latter compound ; it may berecrystallised from glacial acetic
acid, but it exhibits a great aversion for water, not being wet by
it, and consequently the crystals float on water. It dissolves
in hot ccncentrated oil of vitriol, but upon boiling most of it
sublimes unchanged, an evidence of its great stability. Its
vapour is endowed with a pleasant aromatic odour, but inhala-
tion of more than traces is followed in two or three hours by
alarming difficulty in breathing and persistent irritation of the
air passages. Its vapour density was determined in an atmo-
sphere of hydrogen, and indicated the quadruple formul.- , Even
boiling water exerts only a very slight action upon it ; but a
smooth decompo.sition is effected by dissolving in ether, and
repeatedly agitating with water. The acid produced is
deposited from the water in crystals having the composition
(PN05Ho)4-)-2H30. This interesting acid readily decomposes
soluble chlorides, nitrates, and sulphates, forming three series
of salts, in which respectively one-fourth, one-hall, and all the
hydrogen is replaced by the metal. The free acid is so highly
stable that it may be boiled for hours with nitric acid or aqua
regia without decomposition. Further details concerning it,
and the other compounds isolated, will shortly be published.

BIOLOGICAL

WORK ON THE ILLINOIS
RIVER.

T LLINOIS possesses a good Laboratory of Natural History,
in which Prof. S. A. Forbes, with a number of assistant
entomologists and zoologists, carry on investigations of value
to science and the State. A report on the work of the Labora-
tory during the past two years has recently been issue d. To us
the points of special interest with which it deals are (i) the
establishment, in 1894, of a biological station for the con-
tinuous investigation of the aquatic life of the Illinois River,
and ils dependent waters, near Havana; and (2) an elaborate
expeiimental research carried on during the past year to deter-
mine means for the destruction of the chinch bug, and especially
for the dissemination of the contagious diseases of that insect.
This investigation was undertaken by the Laboratory staff,
with the co-operalion of the State Agricultural Experiment
Station.

We have already noted the establishment of the biological
station (Nature, vol. 1. p. 275, 1894), but as it is the first
inland aquatic biological station in America, manned and
equipped for continuous investigation, the following further
details ate interesting. By the kindness of Prof. Forbes, we
are able to illustrate the description with two of the fifteen fine
process plates contained in his report.

The Station was opened just a year ago. Its general objects
are to provide additional facilities and resources for the
study of the natural history survey of the State, now being
carried on by the State Laboratory of Natural History ; to
contribute to a thorough scientific knowledge of the whole
system of life existing in the waters of this State, with a
view to economic as well as educational applications, and
especially with reference to the improvement of fish culture
and to the prevention of a progressive pollution of Illinois
streams and lakes ; to occupy a rich and promising field of
original biological investigation hitherto largely overlooked or
neglected, not only in .\merica but throughout the world ; and
to increase the resources of the zoological and botanical depart-

NO. 1329, VOL. 51]

mcnts of the University of Illinois, by providing means and
facilities for special lines of both graduate and undergraduate
work and study, for those taking major courses in these depart-
ments.

The Station differs from most of the small number of similar
stations^thus far established in the United Stales, in the fact that
its main object is investigation instead of instruction, the latter
being a secondary, and at present an incidental, object only.
It has for its field the entire system of life in the Illinois River
and connected lakes and other adjacent waters, and it is Prof.
Forbes' intention to extend the work as rapidly as possible to
the Mississippi River system, thus making a beginning on a
comprehensive work in the general field of the aquatic life of the
Mississippi Valley, in all its relations, scientific and economic.

The special subject which Prof. Forbes fixed upon as the
point of direction towards which all the studies shall tend, is
the effect, on the aquatic plant and animal life of a region, pro-
duced by the periodical overflow and gradual recession of the
waters of great rivers, phenomena of which the Illinois and
Mississippi rivers afford excellent and strongly marked examples.
This field of research is entirely fresh, and at the same time is
highly interesting and important.

As an incidental, but by no means unimportant, result of the
work, material will be accumulated for a comparison of the
chemical and biological conditions of the waters of the Illinois
River, at the present time, and after the opening of ihe Chicago
drainage canal.

The practical importance of the undertaking, as affording the
only sound basis for a scientific fish culture, will be fully re-
cognised by all who are seeking to apply scientific methods of
investigation to economic problems.

It is pointed out that the Station will also serve as a
centre of interest and activity for University students engaged
on zoological and botanical subjects. Not many years ago
biological instruction in American colleges was mostly derived
from books ; of late it has been largely obtained in laboratories
instead ; but Prof. Forbes believes that the mere book-worm is
hardly narrower and more mechanical than the mere laboratory
grub. Both have sr.ffered, and almost equally, from a lack of
opportunity to study nature alive. One knows about as much
as the other of the real aspect of living nature, and of the ways
in which living things limit and determine each others' activities
and characters, or in which all are determined by the inorganic
environment.

Means are provided by which students, and intending teachers
of biology, may be given a wider knowledge of their subject,
and where they may investigate experimentally the prob-
lems of mutual influences and relationship in the living
world.

Possibly still more important is the opportunity which the
Station will offer, when permanently established and fairly well
developed, to the independent student and investigator,
zoological or botanical, who may desire to pursue his studies in
the field covered by the operations. It is a part of the plan of
organisation and equipment to receive and assist in every
practicable way advanced students and investigators of this
description, from whatever place they may come.

Havana was selected as the site of the Station because of
several unique advantages offered by that locality. Streams
and lakes illustrating practically all the typical Illinois River
situations are to be found there, convenient of access from a
central point, and from each other. An extensive sandy bluff,
commonly well shaded and oozing spring w.ater at ils foot,
borders the river bottom on the east, and introduces several un-
usual features ol interest to the oecologist, besides affording a
clean and hard shore to work from, dry, shady, and well-drained
camping ground, and an abundance of very pure cold water at
all times of the year.

A " cabin boat " was used as a field headquarters, and
stationed on Quiver Lake, two and a half miles above Havana.
It carried the seines, sounding lines, atrial and aquatic ther-
mometers, dredges, surface nets, Birge nets, insect nets,
plankton apparatus, and other collecting equipment, together
with microscopes, reagents, a small working library, a large
number of special breeding cages for rearing aquatic insects,
and a few small aquaria. This boat was provided with sleeping
accommodation for four men, and with a well-furnished
kitchen.

The greater part of the field work was done on seven regular
stations, visited periodically throughout the year ; two on the

594

NA TURE

[Apkil iS, 1S95

NO. 1329, VOL. 51]

Fic. J.— Dc»d Fi^ll and Mimels. Bed of Phclpj Lake.

April i8, 1895]

NATURE

595

Illinois River, three on Quiver Lake, and one each on Phelps
and Thompson's Lakes.

Quiver Lake (Fig. i), in which the headquarters' boat was
placed, is an abandoned portion of the old bed of the river. It
varies in length (when the water is low enough to define it
clearly) from one and a half to two and a half mdes, and has a
usual width of about five hundred feet at low-water mark. It
lies nearly parallel with the main river, into which it opens,
j even in the lowest stage of water, at its lower or southern end,
by about half its greatest width.

Thomson's Lake lies wholly within the bottom lands of the

main river, and iis banks are consequently everywhere low and

i flat. It is five miles in length by about half a mile in width at

' an average midsummer stage. Neither this nor c)uiver Lake

ever goes dry, the water in the deepest places being not less

than three and a half or four feet during the dryest seasons.

1 Phelps Lake (Kig. 2), on the other hand, is a pond about half a

I mile long by a fourth as wide, having neither inlet nor outlet

after the overflow has receded, rarely drying up entirely, but

not infrequently being reduced to a few shallow pools. It

is completely surrounded by a bottom-land forest, and its bed

is a mere shallow depression in the mud.

The results of the first season's work are, of course, but just
beginning to appear. Indeed, the problems to be solved in
such situations have scarcely more than dimly shown themselves
-as yet, but the promise is nevertheless already very interesting.
Notable contrasts in kind and number appear between animals
of the springy shore of river or lake, and those of the muddy
bottom, only a few rods away on the other side ; between river
and lake ; between Quiver and Thompson's Lakes ; between
each of these and Matanxas Lake ; and between all the other
lakes and the temporary pond distinguished locally as Phelps
Lake — comrasts sometimes easily comprehensible ; and some-
times peculiarly puzzling, like that between Quiver Lake on the
one hand, the waters of which are choked in midsummer with a
dense growth of aquaiic vegetation, but contain fewer of the
smaller animal forms (Entonioslraca, and the like) than the
open current of the river iiself, and Thompson's Lake, on ihe
•o her hand, where the water is relatively clear of aquatic
plants but abounds in rotifers and Entomostraca. Still more
curious is the contrast between the similarly situated and very
similar lakes, Quiver and Matanzas, the waters of one loaded
and clogged with plants, and swarming with small molluscs and
insect larvx, and those of the other with scarcely a trace of
even microscopic vegetation, and with a correspondingly insig-
nificant quaniity of animal life.

One surprising result is the abundance of minute life in the
•main siream, which sometimes con'ains a greater abundance
of animal forms than most of the lakes connected with it ; and
another is the relatively small difference beuveen the animals
frequenting widely unlike situations in the same body of wuer.
A large number of new forms were found, especially among
rotifers, worms, and insect larva;. The collections of the
season, (jreserved for detailed study, are included under nine
hundred and fitiyeight collection numbers, representing as
many different lots of specimens. In connection with these.
Prof. Forbes and his assistants are now engaged upon deter-
mination work and other laboratory studies, and ihe preparation
of reports. The papers ami reports embodying these studies
will be printed in the BuUdiit of the Illinois .Mate Laboratory
of Natural History. So lar as possible, each general taxoiiomic
paper will be prece led by a thoroughly practical synopsis of
genera and species, illustrated by figures ol typical forms, and
intended to open up to the student and teacher of natural
history in Illinois many interesting and important parts of the
local zoology.

THE VARIETIES OF THE HUMAN SPECIES}

TN man, as in other animals, we find physical characteristics of
two kintls, external arid internal. The first are principally
those penaining to the cutis and certain cutaneous appendages,
and include the c 'louring of the skin and hair, the structure and
form ol the hair, and also the colouring 01 the eyes. The chief
intern.nl characteristics are the bones from which the form and
figure of all the members are taken, as well- as those of the

t Extracted from a transUtion nf Prof. Giuseppe Sergi's " Lc Varietu
iUmane.'' p blisticd by the Smithsonian Institution.

NO. 1329, VOL. 51]

separate parts of the body clothed with soft tissues, such as
muscles and fat. The cranium is the most important and most
characteristic part of the entire human skeleton.

The cranium is a bony case which encloses a viscus of the
first order, the brain, which in man is, in relation to the animal
series, better developed, both in its forms and functions. It is
known that the brain and cranium, from Ihe embryological to
the adult state, are in a parallel manner and gradually connected
in evolution, and the external form of the one corresponds to
that of the other. Most certainly it is not the cranium which
gives form to the brain of man ; it is more probable that it is the
brain which moulds its organ of protection. Given hereditary
conditions, we may affirm that the form of the cranium is corre-
lative to that of the brain. If we could discover why
the brain lakes or has taken different forms, we would
possibly understand better its correspondence with Ihe
exterior structure of the cranium by which it is surrounded.
We might be able to learn also what functional and
especially what psychological characteristics are united to the
cerebral forms which are revealed by cranial forms. All that is
obscure for us, and also unexplored, because unsuspected ; for
in place of that, and in an inexact manner, the volume has been
taken into account, and therefore the weight of the brain, as
being the only means of making an anthropological diagnosis
of its functional value, the volume and weight corresponding to
the capacity of the cranium.

But besides the cranium commonly called cerebral, there is
the face, which, from the morphologic point of view, is not less
important. The face has generally given more positive means
for distinguishing human groups, not only on account of the
colouring of the skin, but on account of the form and disposi-
tion of its parts, of the nose, of the cheeks, of the molar teeth,
and on account of other characteristics which, when considered
together, disclose differences not immediately revealed by the
cerebral cranium.

The other parts of the skeleton also have difierences more or
less profound in the different ethnic groups, the stature, the
length of the extremities both absolutely and relatively to the
stature and to the trunk ; the thoracic form, and so on. But
such differences are but slightly characteristic in comparison to
those presented by the cranium and the face ; until now, more-
over, they have had but slight value, the reason being that they
are derived from characteristics which are merely secondary

We are ignorant what may have been the primitive type or
the primitive human types, considered in all their internal and
external characteristics ; that is, what skeletal forms certain
ethnic groups of differently coloured skin possessed ; or, on the
other hand, what colour of skin and hair belonged to certain
skeletal forms. That difficultv is caused by a fact easy to under-
stand, by the mingling of different types among each other, and
by the hybrid forms from which man is derived. It is true, how-
ever, that certain hybrid results seem to be limited to certain
regions and to a few human groups ; and that, on account of
this, the elements which have furnished such products may be
learned up to a certain point ; but in the beginning, at least, it
will be necessary to learn the structures of the parts from which
hybrids are derived.

it is impossible not to admit human hybridism, since it is
demonstrated clearly by all anthropologists ; in this direction
America alone shows us a peifect example of experimental
anthropology. It has been determined from observations that
liuiuan hybridism is multiform among all peoples; but what we
learn from the facts relates to the exchange of external charac-
teristics and their mixture with iho-e internal, that is, the
union of the external characteristics of one ethnic type with
the internal characteristics of another type. Thus, one may
observe the colour of the skin and hair with its special form
united to characteristics of skeletons which do not generally
belong to types of that colour, and vict versa. That may be
observed concerning certain characteristics, and not 01 all ; such
as the stature, or the face, with its soft covering, or the lorm of
the cranium only.

If we study oar European populations which are called
white, but which have many gradations of whiteness, we may
note the great mixture of characteristics, a mixture which is
changeable, from which results a great variety ol forms of
individual types, constituted of characteristics dilf. ring from
each other. An analysis must be very accurate and very
ininute to discriminate these different elements which exist
in the composition of the ethnic characteristics of individuals

596

NA TURE

[April iS, 1895

and peoples. These mixtures and these conibinations of
characteristics differ according to the character and number of
elements existing in the various nations of the south, the centre,
or the nonh of Europe. They arise from different relations
with mixed peoples.

What is most important in this human hybridism, so various
and so complex, is the Lick of the blending of the external and
internal characteristics from which new human varieties may
be had. Among the different ethnic elements there exists
only a relation of position, called syncretism, or propinquity of
characteristics, and therefore a facility for forming small
groups. Such a phenomenon has already been recognised in
.\merica, and it is evident in Europe among peoples who
appear little homogeneous, if a careful observation separates the
characteristics constituting ethnic types and those of individuals
iu a mi.xed population.

If there were no other cause for such an absence of blending
among the characteristics of human hybridism, this cause would
exist, that the relations which produce the mixtures are not
equal and constant, but are varied and inconstant. If there
should be the union of two pure ethnic types only, for several
generations, we should be able to derive a hybrid product constant
and fixed, as among animals and plants ; but a third element,
either pure or mixed, arrives in the second or third generation of
man, and so on indefinitely. Thus it is easy to understand
how unstable must be the characteristics of the hybrid, for they
can scarcely survive in one individual for a generation. The
hybrids which follow may have characteristics of different
types, with the tendency each time to have these reappear by
heredity, although not blended and not fixed in the individual.

To this should be added another fact, that of individual
variation, which is present in man, as in other animals,
increased by his constant interminglings, which may be con-
sidered stimulants of this phenomenon, as has been suggested
by Darwin and Wallace.

Hence, I conclude from my observations, that human
hybridism is a syncretism of characteristics belonging to many
varieties, and that these do not modify the skeletal forms as
do individual variations, and that hybridism m.iy affect
different parts of the skeleton, constituting characteristics in
themselves distinct. The stature, the thoracic form, the propor-
tion of the long bones, may be united with external character-
istics differing from each other, as well as from different
cranial structures. The cranial form may be associated with
different facial forms, and inversely. It happens, however,
that the structures taken separately remain in part unvaried in
the hybrid constitution. The face preserves its own character-
istics in spite of the union of different cranial forms ; so also
the cranium preserves its structures, associating them with
difl'erent facial forms. The stature preserves its own pro-
portions in spite of its asociations with different cranial
and facial types, and in spite of the different colouration
of the skin and the form and colour of the hair. All
this may be affirmed, particularly of much larger human
groups which, according to external characteristics, may be
considered much nearer than they really are in geographical
position, as the so-called white races in Europe, the negroes in
Africa, in Melanesia, and so on.

Now, granting that all peoples exhibit the characteristics of
hybridism in the manner just described, it will be necessary to
learn how races, groups and human families may be classified.
Let us observe for a moment the classification by means of
external characteristics, most common among anthropologists
from Linnxus to Quatrefages and Klower, and we shall see :

(1) That the colour of the human skin in one great group of
a type, such as yellow, black, or white, is of different grada-
tions, and not uniform.

(2) Since, as above stated, all peoples, at least in a great
mea.surc, are composed of hybrid elements, it happens that dif-
ferent elements are united under one category, which is, in this
instance, the colour of the skin.

(3) We must not forget that the external characteristics are
more easily lost, and much easier to acquire, by intermixture
and heredity.

A curious example of what I state is found in human classifi-
cation according to <,)uatrefages, which perhaps is now the
most complete, considered only as a classification by external
characteristics. He place the Abyssinians within the white race
notwithstanding that Ihey have the negro colouring, and he
do€« so because he believes that the characteristic form of the

NO, 1329, VOL. 51]

skeleton or internal characteristics of the .\byssinian5 are those
of the white race. This is without doubt inconsistent when the
principle of classification by colour is accepted. This incon-
sistency itself shows the defect of the method and of the prin-
ciples mentioned as applied to human characteristics and their
combination.

(4) Finally, as we perceive, the theory is not justified that
man be classified as a single species with three, five, or more
variations.

If the characteristics which present greater stability are
internal or skeletal, they should serve for human classification :

(a) Because, notwithstanding amalgamation and consequent
hybridism, the characteristics originating in the skeleton are
persistent.

(if') Because they may be taken as fixed points with which
other characteristics may be associated, and may be also external,
as I shall demonstrate.

{c\ Because, finally, the internal characteristics can demon-
strate the full number of divisions and subdivisions in classifying
ethnic groups, and in analysing peoples which are a combina-
tion of a great number of hybrids.

It remains to determine which internal characteristics should
have the preference in deciding the value of types for classifica-
tion. If we consider the human skeleton, with that object in
view, we find three parts which may serve for that purpose,
the cerebral cranium, the face, and the stature, with the long
bones.

Staltirt. — The stature is a good, but an insufficient character-
istic, because it gives only linear differences, and in its value
resembles greatly other external characteristics, and is associated
with all the most dissimilar derived from the skeleton.

Face. — The face offers very important characteristics for
classification, because it shows typical differences in the ethnic
groups. The face has given more points for the distinction of
human types than the other parts of the human body, and
would appear better adapted for that purpose than the cerebral
cranium. But the face is more disposed to individual variations
than any other part, because it is very complex, being composed
of numerous small bones, clothed with muscles which have
continuous and important functions relating to the physiognomy,
to the expression of psychical conditions, and to the nutritive
functions. These facts render its typical form less constant,
and are, or may be, the cause of a multiplication of types.

Cranium.— The cerebral cranium is itself also liable to varia-
tions. More than any other org-in, it exhibits a phenomenon
often observed and clearly demonstrated by me, that is, the
persistence of forms from immemorial epochs, and their repro-
duction through numerous generations notwithstanding amalga-
mation with other types. I have demonstrated such a persistence
of cr.inial forms in the varieties of the Mediterranean from the
Neolithic and from the most ancient Egyptian epochs ; other
anthropologists have recognised such persistence m European
types of the Quatenary epoch, and in others, very ancient, from
America. This cannot be said of the structure of the face.

Therefore if the human cranium is accepted as a basis for
the classification of human groups, positive results may be had :

(a) In groups which have been subjected to mixture in what-
ever epoch or however ni.iny times, the distinctive ethnic
elements may be discerned by examining the cerebral cranium
only, which, remaining unaltered in type, may be found united
by hybridism with other internal and external characteristics.
For the cranium is the point about which revolve all other
variations of form, either in hybridism or in the human form
itself.

(i) Knowing the cranial types of a people who seem more
or less homogeneous, we are sure of learning of what and how
many ethnic elements it is composed, notwithstanding the
hybridism present.

(<•) Having classified all the cranial types in different regions
and among different peoples, we may learn by their geographical
distribution the numerical extension of types and also their
geographical origin ; that is, the place of departure and the
course of emigraliin and dispersion of such forms.

((/) Then it will be easy to learn what cranial characteristics
arc found among populations which already have ethnic names,
ancient and modern, and to discover among them points of
similarity and difference.

Being, therefore, obliged on account of universal human hy-
bridism to select as a guide to classification the most important
and the most useful of the internal characteristics, we find

April i8, 1895J

NA TURE

597

greater advantages in choosing the human cranium, about which
all the other characteristics, internal and external, are grouped.
If we select one characteristic, or a number of variable charac-
teristics, we shall find ourselves in the same position as other
anthropologists who classify by external or accessory traits. It
follows that, accepting the cranium as the principal internal
characteristic, we impliedly accept the brain in its various
forms, and the brain is the most important of human organs.

The classification of man by means of the cranium alone is by
no means new. It will be well to consider these schemes, from \
that of Retzius down to the last, that of Kollmann. Nor,
indeed, is the conception of the importance and superiority of
the cianium for distinguishing ethnic groups by any means
recent. To show that, we have but to refer to the enormous
work which has been done, from Morton to Davis and Thur-
man, from Broca to G. Retzius, to De Qualrefages, to von
Holder, to Ecker, to His and Rutimeyer, to Virchow, to Ranke,
to others still more numerous, in Italy, from Nicolucci to
Mantegazza. '

Notwithstanding so much labour expended on the human
cranium, satisfactory results were not reached, nor, indeed, I
may affiim, have we yet reached them, at least not in the signi-
fication which I intend these results to have. The fault lies in
the nature of the method of studying the human cranium, and in
the value attributed to craniometry.

The classification of Retzius is based upon a single charac-
teristic of the cranium, which, however, is merely the numerical
expression of the norma verticalis of Blumenbach, thit is, the
cephalic index.

According to Retzius we have only two forms of crania, the
long and short ; though, in fact, many forms of short and long
crania are found differing very much from each other.

When craniometry was developed in a systematic manner,
following principally the work of Broca, it appeared the key of
anthropology, and took the first place among means of investi-
gations, as being the most effectual method for distinguishing
human races. The French exaggerated its value ; the Italians
followed with zeal, in spite of the scepticism of Mantegazza,
the head of the Florentine school of anthropology ; the Germans
have been more rational, and with them the Swiss, represented
by His and Rutimeyer. At the head of them I would place
Blumenbach, who based his small but valuable book upon a
rational foundation.' The Germans try to establish crjinial
type almost or entirely independent of the cephalic index ; as
one may see from the works of von Holder, of Ecker, of His
and Rutimeyer, of Virchow, of Kollmann, of Ranke and others.
In my opinion the German method is an approximation to the
truth, but unfortunately the conception of type is undeveloped
and, I should say, has remained rudimental, because cranio-
metry, like a pernicious weed among the grain, injures the
harvest. Virchow, the most pronounced scholar in anthropo-
logy, and the man who has studied more than all others the
crania of all peoples, believes that the germ of a .sound anthro-
pology .should develop from it, and concedes only a secondary
value to craniometry.

According to my observations upon craniometry, which has
now become cabalistic, especially in France, on account of the
abuse of measures and numerical ciphers, the indices of the
cranium and face are taken as a means of distinguishing races,
human groups, as we might call them, and other measures are
either omitied or applied only to individuals. In order to br
convinced we should carefully and conscientiously study the
craniometrical works of Dr. Danielll, of Florence, upon the
Nias and Bengalese. The author has not been able to find
satisfactory results after per-evering researches, but whoever
would seek evidence of individual variations will find more
than enough. It .seems to me, therefore, that the method by
measurement may serve this purpose, that is, to discover
numeiic.Tlly individual differences, but never those typical of a
race. Hut such a discovery is useless, since we are all con-
vinced of the existence of individual differences. I will there-
fore add that such differences, to be valuable, must be sought,
not among forms differing from each other, but among in-
dividuals of the same type. That implies, therefore, neces-
sarily and always, the search fir types and their distinction,
which is not possible by means of ihe craniometrical method.

I( it were true, and there were no doubt respecting the value

of th..- celebrated cephalic index in determining crani,il forms, it

would follow that all human crania of whatever type and volume

1 " De generis li«[n.ini varietate nativa." Ilia edit. (Guttingcn, lygs)

should be placed in the three categories of dolicho-, meso-,
and brachycephalic, or of hypsi-, ortho-, and chamKcephalic.
Thus all the populations of the earth, either of white, yellow,
black or red skin, would have crania belonging to the three
categories. A classification solely according to the cephalic
index is therefore an absurdity. It is incoherent and without
meaning, as are those of Retzius and Kollmann.

This conclusion is so true that such anthropologists are obliged
to add descriptions to the forms of each part of the cranium, in
order to distinguish it, recognising the insufficiency of cranial
data. Such descriptions can, to a certain degree only, supply
the defect of the method, but they always remain incomplete,
and leave the forms or types of the human cranium of various
populations and regions indefinite. The French school has gone
still farther, and has supplied the deficiency with an infinite
number of measurements, which only increase the obscurity,
leaving the conception of the form moie uncertain, and fatiguing
the most patient student, who becomes convinced of never
reaching any satisfactory result from such a confused accumula-
tion of numbers.

In order to render classification more definite, or for the sake
of finding a second characteristic which might be associated
with the cephalic index, Retzius turned his attention to the
prognathism and the orthognathism of the molar teeth ;
Kollmann to the facial index. Use could be made of the nasal
index instead of the facial, or the orbital index, or any isolated
characteristic, and we should have the same results. The com-
binations given by Retzius and Kollmann are possible, but
cannot indicate races or varieties, from the fact that they are
hybrid associations.

I need not make a longer demonstration of what I have
affirmed, that classifications of human gi^oops have been
attempted by means of the cerebral cranium, but have not been
successful on account of deficiency of method ; and that the
craniometrical method, still so undeveloped, has not yet, nor
cannot, give those results while there is an exaggeration of an
exact principle, that of expressing numerically facts relating to
the cranium. It seems to me, after several years of study, and
after having adopted the accepted form of craniometry, for
want of a better, that it is time to establish for our use and for
the study of the variations of man, a natural method, resembling
that which is used in zoology and botany, and of which I laid
the foundation about two years ago.

With Ihe observations and the methods which I propose, I
believe that many errors will be eliminated from anthropology.
Those errors have been accepted because we have never
possessed natural scientific methods for the study of human
classification, such as we have in zoology. Blumenbach, in a
valuable little book, attempts to apply the zoological method to
man, not cnly for classification, but for the explanation of the
causes of animal and human varieties. De Quatrefages, in his
last work, employs the same method and the same scientific
freedom. Unfortunately the followers or successors of both
have only followed their masters in form, but not in method.
Blumenbach, who, after various researches, reduces the human
species to five varieties, finds, however, that human variations
are infinite in number. If his method had been followed strictly,
the number of human varieties would long ago have been
increased, both in respect to the structure and the cranial forms.

The neglect of such methods and the failure to distinguish
human varieties by means of the cranium has caused a curious
error, that of regarding certain forms which are typically normal,
as pathological, as I shall have occasion to demonstrate in the
future when I speak of cla.ssified forms. This is apt to happen
when new and unrecognised forms are placed before the observer.

One of the important characteristics in classifying the cranial
varieties of man is the frania! capacity, which has a direct
relation to the volume and weight ol the brain ; hence classifica-
tion by crania means the classification of brains estimated by
their form and external configuration. Its importance is for us
increased by the fact that that which we find among races of
animals occurs also in man ; that there are races ol small and
large animals, races differing in size. This is also repeated in
man, and we therefore have large, medium and small varieties,
as measured by stature. The orrgin of such varieties is perfectly
analogous to that in other .animals. Nor is it an accidental
phenomenon, because it is confirmed by heredity, through
numerous and indefinite generations.

I have concluded, in studying cranial varieties morphologic-

NO. 1329, VOL. 51]

598

NA TURE

[April i8, 1895

ally as human varieties, that if, by their characteristic structures,
that the volume has a dirfct relation to the form, in other words,
many forms have limited and definite capacities, while other
forms have sub\-arieties differing in capacity. Such varieties are
analogous to the stature of the large and small varieties of
animals. The cranial capacity, therefore, while it is one nf the
integral characieristics of the cranium in regard to its classifica-
tion, is also the indication of diflferent varieties according to size.
I discovered this fact when I clafsified for the first time the crania
of Melanesia, and sub'e quently I defined it more accurately when
I examined and classified thousands of other human crania.

This fact points to acorrectionof the value of cranial capacity
and, therefore, of the weight of the brain, until now calculated by
the average without disliuciion among different varieties. The
cranial capacity of man varies from looo cc. to about 2000 cc. in
the masculine sex ; this enormous difference is admitted as indi-
vidual variation, and it is thus conceded that there may be a least
limit of noimaliiy possible which can be ascribed to the function of
the biain, crania which descend to 1150 cc. being considered as
pathological microcephali, according to Broca, and more or less
according 10 other anthropologists ; giving, on the other hand,' a
great value to a large capacity. Both conclusions are contrary to
the real significance of the (acts. I have found normal mascu-
line capaciiies of 1000 cc. and a little greater, representing
small human varieties, not being sporadic and individual phe-
nomena ; and, on the other hand, anthropologists have registered
for eminent men, like Dante, Gauss, and others, very mediocre
capacities, even very low, while for ordinary men they have
recorded a much higher capacity. I have found in Melanesia
normally constituted heads absolutely microcephalic, together
with roegalocephalic heads, belonging to varieties which have
the same social value ; they are both inferior, some anthro-
pophagous, and live mixed together as one people, That which
I have asserted concerning Melanesia may be said of the ancient
and modern populations of the Mediterranean, among which are
the Sicilians, the Sardinians, and the inhabitants of Central and
Southern Italy ; and I do not believe it can be said that there
are no signs of human superiority in those regions. There are
not, therefore, individual differences so great as from 1000 to
1500 cc, and from 1 500 to 2ccocc., but characteristic differences
o( variety in human forms. The general average I therefore
maintain is inexact and also arbitrary, because it is the
average of incommensurate quantities. The exact average is
that between irdividu.ils of the same variety, and the diffeience
is the tiue individual variation.

But I here is another error to correct, due to the signification
which I am able to give to varieties distinguished by means of
my method. It is considered by some a demonstrated fact that
the cranial capacity has been increased in the course of social
cvolutii-n from prehistoric epochs to historic times. Eminent
men have affirmed it, but I have already placed their conclusions
in doubt, because the facts do not appear to me evident and
affirmative, I wrote some years ago : ' "The most important
physical evolution of man would be that which related to the
organ of the menial functions, the brain. But the facts are still
very doubtful and very obscure which relate to the weight and
volume of the brain, and consequently to the cranial capacily.
In a recent work of Prof. Schmidt, I find that the cranial
capacily of the ancient puie Egyptians is 1394 cc. in the mas-
culine, and 1257 in the feDiinine sex; in the pure modern
Eg)piians it is 1421 in the males, 1206 in the females. Accord-
ing 10 th'te figuies there would be an increase of the cranial
capaiiiy nf the modern over the ancient males, but a deciea!>c
in the females. The nveise would be true nf the Egjpto-
Nubian cianium, which u 1335 in the modtrn males, and 12058
in the ftniaes. Broca luuiid that the Egyptians of the IV.
D)nast) hail, males 1534, females 1397 cc. ; those of the XI.,
males 1443, lemalcn 1328; aid. finally, those of the XXIII.,
the mi'Bi leceni, malea 1464, females 1322. There would be
in such a case no increa^e, but decrea!>e, but that is not
po>sil>lc ; the causr of these factt lies in the mixtures of races
at dUertnl limci. and in diflcrenl proportions. "

Jvo» 1 cnniluilc from my recent studies upon (he Egyptians
of innciciil dynasties, liom the moit ancient to the present,
thai iicc4frding 10 n<y niethcifl ol da^'sificalion there ate capaciiies
of I260CC., of 1390, iif 1480, of 1550, of 1710, and still other
capakitici diflenii|> accoruing to the varietlcii determined.' As

1 "H.I

1 "Ol

(Archives

11." (Review of Scirntlfic PfiiloBopliy, i83B, Milan.)
I'niMiiive Inhabiianu of the MediternincaD."
,;y, Florence, t^i, vul, xxit)

NO. 13.9, \OL. 51 J

is easily understood, a general average necessarily alters the
facts, according to the number of varieties which enter as
components of the average in the different series in anthro-
pological museums; hence the curious results above indicated.

Another important point is as follows :

" But the fact which surprises us is the high figure of the
capacity given by prehistoric crania. The masculine crania of
Lozire have given 1606 cc, the feminine 1507 ; aho of Lozere,
masculine 157S, feminine 1473 ; crania from the pie/ ra /cvigala,
masculine 1531, feminine 1320 ; the contemporaneous Parisians,
masculine 1559, feminine 1337. The approximate average of
crania from the fietra Irtigala is 1560, equal to that of modern
Europeans, as is related by Topinard." '

In another of my recent works, I have demonstrated that of
the crania of the neolithic age- the IsobatIiyflatycct>halus has a
cap.tcity from 1230 to 1405 in the feminine, and the Eiicaiiipylos
varies from 1470 to 1564 in the masculine. The two varieties,
still persistent in Sicily, do not vary in capacity in the modern
series, and at the same time show that in the neolithic epochs, as
among modern populations, large and small varieties are found,
just as the same types are now found through persistence of forms.

From this it is evident how much there is to reform in
anthropology when we study by natural methods facts until the
present misinterpreted, respecting the classification as well as
the physical and psychological characteristics of man in time and
space. Perhaps in the future, when we know all cranial forms
by natural classification, it will be possible to find a correspond-
ence of psychological characteristics in populations according to
the predominance or superiority of types, a fact which has until
now escaped research, because the capacity of the cranium in its
absolute sense is not in correlation to the development of the
mental functions, notwithstanding what is commonly affirmed.

The following are the varieties into which Dr. Sergi classifies
the forms of skulls in \.)\e norma verticalis of Blumenbach : —
(i) Ellipsoid (ellipsoides) ; (2) Pentagonoid (pmtagonoidts) \
(3) Rhomboid (rlwmboides) ; (4) Ovoid (pvoidei) ; (5) Sphenoid
(sphenoidts) ; (6) Spheioid (sphicroides) ; (7) Byrsoid (liyrsoidts) ;
(8) Parallelepipedoid {paral/eUpipedoidts) ; (9) Cylindroid
(cylindroidts) \ (10) Cuboid (.'Kfo/rtt'.r) ; (11) Trapezoid (Irape-
zoides) ; (12) Acmonoid (acmoitoides) ; (13) Lophocephalic
(lopJwcephalus) ; (14) Chomatocephalus {chomatoctphalus) ;
(15) Platycephalic \plalycephaltis); (16) Skopeloid (skopeloides).

UNIVERSITY AND EDUCATIONAL
INTELLIGENCE.
We have received a verbatim report of the interview which a
deputation from the Association of Technical Institutions
recenily had with Mr. Atland. Several suggestions were made,
some of which have already received the at cntiun of the Science
and /.It Department. Prof. Weriheiiner pleaded for an ad-
visory voice in the construction of the Department's schemes
before they were finally adopted, in a manner similar to that by
which the Education Depanmer.t allowed the managers of public
elementary schools to express their views on the Co le under
which they had to work before it was finally a lopted. Mr.
Acl.ind, in the course of his reply, said it was the intention of the
Department not to publish near the summer months an) thing
which will lie in the nature of an imporlani change. The recent
form dealing with organised science schools had been issued
early, with a view to emboiiying it in the Diieciory next
autumn, the Depariment in the meantime being open to sugges-
lions. During ihe course of the Vice-President's remarks, the
question of the pulilicaiion of the dales of the May exauiiniiions
was laiscdgand, in reply loan inqui y. Sir John Donnellysaid
lie saw no difficulty, if the schools wanted it, in publishing in
May ihe dates of ihe subsequent May examinations. As 10 the
qucsti n of the proper basis tor the calculation of the (iovern-
iiicni giant, Mr. Acland exprc^sell the hope that some day a
part 01 the principle, which is shuitly to be applied 10 organised
science sihools, will aho be applieil to evening classes ; that
IS to say, there is every prospect ihat the grants will in a year
or two be awarded in. re on the Inspector's lepoits as to the
soundness of ihe teaching than on the results of examination.

TllK.RE are 119 Universities in the world, says the Oxfora
Univeisily Exlcmion Gazette. Dr. Kukula in his list names

1 Sec " Human Evoltilion."

•1 " Crania uf Ihe Neolithic Age." (Boll. Faletnol. luliana, Parma, i89a.>

April i8, 1895J

NA TV RE

599

1 114, but he oiniis ttie U.iiversitiei of Loidon, of Paris, of Ihe
State of Naw York and of Wales, aad th; N'iw Univeriity of

1 Brasiels. EKclaiin^ the firit three, which, bein^ of the
Napoleonic type, hxve n> red lent stu lents, thi un ler^ri i.ii'e
population of ihi Univ^rsitie; of the vv)rll is eitimitiil bv thi;
aca'lernic statistician as amounting to 157,513 persjns. B :rlin
is the mo;t populous University, Urbino the smilleit. Tn;
first has 7771 studints, the latter only 74. In pjint of mm
hers Oxford comes tenth on the list; Cambridge, twelfth;
Victoria, sixty-fourth, and Durham ninety-eighth.

SOCIETIES AND ACADEMIES.
London.

Royal Society, March 21. — "On the D.'velopm;nt of the
Branches of the Fifth Cranial Nerve in Min." B/ A. Francis
Dixon.

In this paper "detailed description; of the fifth nerve branches
are given for five ditTerent stages of the human emliryo, begin-
ning with an embryo of foir weeks, at which time merely
the three miin divisions of the nerve are represented, and
ending with one of the eighth week. Tne observations on the
human embryo have been checked by further observations on
rat embryos, and an alin )st conplete correspondence between
the two has been mide out." In mammals, the three divisions
of the fifth nerve are found to rise in lependently from the
Gasserian gingli)n, and the nisal nerve is foanl to be the first
representative of the ophthalmic division, the frontal being
formed later. In like manner, the inferior dental nerve repre-
sents the first formed in'erijr maxillary nerve, the lingual
branch appearin.; later. No special ganglion is present either
for the na<al or for the ophthalmic nerve in mammals in the
sense of a ganglion of a posterior nerve root. Tne ciliary
ganglion does not represent such a ganglion, and when first
found is more closely connected with the f mrth and frontal
than with the thirl and nasal nerves. The fourth and frontal
nerves from an early period are closely connected. At the be-
ginning of the sixrh week nearly all the name! branches of the
fifth nerve of the adult are represe ited in the embryo ; also at
this lime the accessory ganglia of the fifih nerve are recognisable.
No evidence was found to show that the cells of these smaller
ganglia are derived direcily from those of the Gasserian.
None of the different nerves which in the adult connect the
fifth with the o'her cranial nerves are to be considered branches
of the fifth nerve ; thus the chorda tympani anl the Valian are
found to be derived from the faciil, and the nerve of Jacobson
from the Glossopharyngeal.

"On the Conditions affecting Bacterial Life in Thames
Water." By Dr. E. Frankland, F. R.S.

Since May, 1892, the author has been making monthly deter-
minations of the number of bacteria capable of development on a
peptone-gelaiine plate in a given volume of Thames water
collected at the intakes of the metropolitan water companies at
Hampton. The number of microbes per cubic centi netre of
water varied during this time between 6jl and 56,630, the
highest numiiers having, as a rule, been found in winter or
when the tempera'ure of the water was lo*, an 1 the lowest in
summer or when the temperature was high.

The complete observations demonstrate that the number of

microbesin Thames water depends up m ihe rate of flow of the

river or, in other words, upon the rainfill, anJ but slightly,

; if at all, upon cither the presence or absence of sunshine or a

I high or lovv temperature.

With regaid to ihe effect of sunshine upon bacterial life, the

j author remarks that the intr:resting researches of Dr. Marshall

\ Waid leave no doubt that sunlight is a powerful germicide ; but

I it is prob.ible that iis potency, in this respsct, is greatly

j diminished, if not entirely annulled, when the solar rays have co

I pass through a straium of waier even of compiratively s nail

' thickness before they reach the living organisms. If this he the

case, it is held 10 tie no matter for surpri-c t'lat the eif-'Ct of

sunshine up m liacterial life in the great mass of Thamis water

should be nearly, if not quite, imperceptible.

Geological Society, April 3 — Dr. Henry Woodward,
F.R.S., Pre-id^n', ill ihe chair. — Dr. K. de ICroustchotf, St.
Petersburg, was cl.cted a Foreign C irrespon lont of the S iciety,
— Physical features and geology of Mauritius, by Major H. de

NO. 1329, VOL. 5 1]

Haga Hsig, R.E. The author gave full details of the physical
geography of the island, including the nature and composition
of the mountain ranges, the depth of the ravines, the occurrence
of caverns in the lavas, and the character of the coral reef sur-
rounding the island. Information was furnished concerning the
neighbouring islands, and reference made to the possible former
existence of an extensive tract of land at no great distance from
Mauritius. — On acomparison of the Permian freshwater I.araelli-
branchiata from Russia with those from the Karoo formation of
Africa, by Dr. Wladimir Amalitsky, Professor of Geology in
Warsaw University. The freshwater shells from the Russian
Permian deposits belonging to the gen\is]Pa/affmuU.'a are also
known from the Karoo beds of South and Central Africa, as
pointed out by the author in 1S92. lie had recently had the
opportunity of studying the actual specimens from the Karoo
beds, and found in them species of the groups Palcomiilela
Inostranzewi, P. Kryscrlingi, P. Verncitilii, and P. Miircfii-
soni ; also of a new.genus, the forms of wdiich he had previously
referred to Naiadites, Dawson. All these groups are found
also in Russia, and a list was given of species lound in the
upper horizons (A, B, and C) of the Permian beds of Russia and
in the Karoo beds. These upper beds of Russia have been de-
termined by the author as the freshwater equivalents of the
Zechstein ; consequently the Beaufort beds of the Karoo series,
if considered as the hornolaxial equivalent of the European
strata referred to above, should be regarded as Upper Permian.
The Upper Permian group of freshwater lamellibranchiata of
Russia, which bears traces of genetic relationship with the Car-
boniferous .\nthracosida;, and which was already well repre-
sented in Permo-Carboniferous and Lower Permian times, is,
accorling to the author, much older than the African fauna of
the Beaufort beds. These may be concluded to have migrated
from Russia, the Gondwana beds of India having probably been
the connecting-link between all these deposits. The author
gave a description of the fossils of the Karoo series which he
had examined, including a diagnosis of the new genus in which
he placed the fossils already alluded to as having been pre-
viously referred to the gsnai Naiadites.

Paris. '

Academy of Sciences, .\pril 8.— M. .Marey in the chair. —
On the Huted spectrum, by M. II. Poincare. A mathematical
paper in which it is shown that a complete analysis of the
phenomena of Fizeau and Foucault's experiment confirms
Fizeau's deduction concerning the pernanence of luminous
movement during a large number of oscillations. — Official
plans and reports relating to the removal of the capital of
Brazil to a new site, by M. II. Faye. A series of reports
printed in Portuguese anl French. The district in which the
proposed new site fora Brazilian capital is situated lies between
the par.allels 15" 40' aad l5' 8' and the meridians 3° iS' and
3° 24' at an altitud; of above looo metres. — Structure of the
hymen in a species of Marasmiiis. An abstract of a memoir
by M. 1. de Seynes. — On substitutions, by M. Zjchios. An
algebraical paper. — Rem )v.al of th; Brazilian capital. A letter
to M. Faye, by M. Cruls. A short account of the main
features of the survey work undertaken on the new site. — On
geodetic work in the basin of the Amour, by M. Venukoff. —
On the determination of the mass of the cubic decimetre of dis-
tilled water at 4", by .M. J. Mace de Lepinay. Tnis datum is
yet imperfectly determined. Shuckhurg and Kater give
looo"4So grams, whereas Stampfer finds the value 999'653
grams. Tne author proposes a new method of d:termination
by which he expects to determine this constant within 6 mgm.
The proposed methoi includes (i) the study of the geometrical
form and dimensions of a certain solid as related to the
standard metre, (2) the measurement of the loss of weight of
this solid immersed in pure air-free water at its temperature
of maximum density in terms of the standard kilogram. Toe
solid taken is a parallclopipedon formed of transparent quartz.
Its thickness in different directions will be examined optically
by means of Talbot's fringes. — New apparatus for the measure-
ment of the specific inductive power of solids and liquids, by
M. H. Pcllat. — On a new form .of specroscipe termed the
" hcrna spectroscope comparateur, " by M. M. de Thierry. — On
a simple experiment demonstrating the presence of argon in
atmospheric nitrogen, by M. Gunlz. The author obtains argon
by replacing magnesium by electrolytic lithium. Owing to the
lower temperature at which lithium completely absorbs nitrogen,
it is possible to pass atmospheric nitrogen over several heated

6oo

NA TURE

[April i8, 1895

iron boats containing lithium, and collect argon over mercury at
the exit end of the apparatus.— On the spectra of selenium
and some natural selenides, by M. A. de Gramont. The
minerals examined are : Berzcline Cu, Se, Zorgite (PbCuJ Se,
Clausthalite PbSe, Eucairite Cu„ Se.Ag._.Se, Guanajuatite or
Frenzclite Bi.Sej.— On the estimation of thiophene in benzene,
by M. G. Deniges. Two methods are given, both depending
on the use of the mercury reagent previously described. In
aqueous solution the reagent precipitates the compound (SOj
HgOHg>».C,HjS «»hen heated with the impure benzene
in a closed flask at loo= for about fifteen minutes with frequent
shaking. In methyl alcohol solution the precipitate SO^tHgO);
Hg.CjHjS is produced; in this case the benzene is
miscible with the reagent, and hence the reaction is much
facilitated. — On the action of potassium permanganate on
various organic substances, by M. E. Maumene. — On the
calcium phosphate of milk, by M. L. Vaudin. The
conclusions are drawn that: (l) Milk contains citric acid as
alkaline citrate, which aids in keeping its calcium phosphate in
solution. (2) This solution occurs owing to the effect of lactose
in preventing the precipitation of calcium citrate from solution.
(3) Every influence modifying or destroying the molecular
equilibrium of the salts dissolved in milk, tends to precipitate
tricalcic phosphate together with calcium citrate. — The sand-
stone of Taveyannaz and its relationships with the " flysch,"
by MM. L. Duparc and E. Ritter. — On the calcium carbonate
of lake-waters, by M. Andre Delebecque. — On the connection
of latitudinal displacements of lines of barometric maxima
with the movements in declination of the moon, by M. A.
Poincare. The mean atmo'pheric conditions are powerfully and
regularly influenced by the moon at each tropical revolution,
and at each revolution of the node.

DIARY OF SOCIETIES.

LONDO.N.

LiMS'KAN SociBTT, at 8. — Observations on the Loranthacea: of Ceylon :
F. W. Keeble.

FRIDA K, April 19.
OoEKRTT Microscopic Club, at 8.
Malacolocical Society, at 8.

SATURDAY, K-emi. 10.
Geologists' Association (Cannon Street Station, at 2.30. — Excursion to
Charlton. Director ; T. V. Holmes.

MONDAY, April m.
Medical Society, at 8.30.

TUBS DA Y. April 13.
Royal Institution, at 3.— Alternating and Interrupted Electric Cur-
rents; Prof. G. F .rbes, F.R.S.
Institution op Civii Engineers, at 8.

Royal Horticultural Society, at i.— Conference on Primulas.
Royal Statistical Society (Koyal United Seivice Insiiiution), at 5.—
Progress of Friendly Societies and similar li(>.titutions dunng the Ten
Years 1:84-94 : E. W. Brabrook —Some Ijtuslratioiis of Friendly Society
Finance ; Rev. J. Frome Wilkinson.
Royal Medical andChirukgical Society, at 8.30.
Royal Photographic Society, at 8.
Society of Antiquaries, ai 2.

tyEDNESDA v. April 24.

Institution op Mecmasical Engineers (Royal United Service Institu-
tion), at 7.30. — Di'cus^ton of the GuxerninR of Steam- Eogincs by
Throttling and hy Variable Expansion : CapUin H. K. Sankey.— Ihiid
Report 10 the Alloys Research Committee: Prof. W. C. Roberts-Austen,
C.B., F.R.S.

Geological .Socip.tv, at 8. -On the Shingle Bedsof Eastern East Anglia :
Sir Henry H. Howoith. MP., F.K.S.— An Experiiieni to illuslraie the
Mode of Flow ofa Viscous Fluid: Prof. W. J. Sjlla.. F, R S.— Supple-
menlary Notes on the Syslcm.nic Position of the Trilobiles: H. .M.
Bernard.

British Astronomical As»c'*tion, at 5.

Society op Arts, at 8. ^

THURSDA V, April 25.

RoTAL Society, *l 4 30. "

Royal Institution, at 3. — The Lit^uefaction of Gases: Prof. J. fJewar,
F.R.S.

Camera Club, at 8.15. —PhotO'etching Printing : Leon Warnerlce.

N iM isMA Tir Society, at 7.

' "lETV. at 8 — 7heArii,nof Nilro%yl Chi 'ride on Amides:

■.:. F R S.,and Dr. M. O For-i-r. - 1 he Action of Nitrisyl
:tr... i> ^ nnd A,partic Acid : l.a:v t-rota'ory Chlorosticcinic

AciiJ^ Vf
Non.lumir
tuent '.f 1
Nilr
Iicr.7

S . and H. J. Mar.h.,li.-On a Pr.>(>erty of the
ric Coal Gas FUii.e L T. Wri^hL— A Con.ti-

',\:K. G. P.'fkin an'l J. Gclilatd. — Potassium

l>i*eTS. F R-S., and I'. H ,wa.— D.oiiho-sub-ti|UteJ

r J. J. Sudb riiURh — Hyd",l>sis ot At alic Nilriles

'" I I '~'i III "xiRh. - Action of .S diuin bthylate
iih

•■s (the 5>ociety of Arts), at 8.— A
-.. .:.^- .... i!:resi4 in Sheet Iron. Pfol. J. A.

Lwing, F.H.b.

NO. 1329, VOL. 51]

FRIDA Y, .\PKiL 26.
RovAL Institution, at 9. — The Effects of Electric Currents in Iron on

its Magnetisation ; Dr. John Hopkinson, F. R S.
Physical Society, at 5. — .\ Theory of the Synchronous Motor : W. G.

Rhodwell. — Note on a Simple Graphic Interpretation of the Determin-

antal Relation of D)*namics: G. H. Bryan.
Clinical Society, at 8.30.
Instituton of Civil Engineers, at 8. — Brine Pumping : Bernard

Godfrey.
Institution of Mechanical Engineers (Royal United Service Institu-

tionX at 7.30.
Epidb-miological Society, at 3.— Immunity : Dr. Washbourn.

SATURDAY, April rj.
Royal Institution, at 3. — Enelish Music and Muscal Instruments of

the Sixteenth, Seventeenth, and Eighteenth Centuries ; Arnold Dol-

metsch.
Ghologists' Association (St. Pancras Station), 'at 9 am. — Excursion to

Brigstock, Geddington. &c. Directors ; B. Thompson and W. D. Crick.
Royal Botanic Society, at 3.45.

BOOKS, PAMPHLETS, and SERIALS RECEIVED.

Books.— Field- Path Rambles: W. Miles, series 8 (Taylor).— Alembic
Club Reprints — No. 11 : Essays of Jean Rey (Edinburgh. Clay) — Results
of Rain, River, and Eva poration Observations made in New South Wales
dunng 1893: H. C. Russell (Sydney. Potter). — Progressive Revelation:
E. M. Caillard (Muiray). — The Schott Methods of the Trcaimenl of
Chronic Diseases of the Heart : Dr. W. B. Thome (Churchill) —Wayside
and Woodland Blossoms: E. Step (Warne). — Economic Classics: T. R-
Malihus (.Macinillan). — Problems and Solutions in Elementaiy Electricity
and .Magnetism : W. Slingo and A. Brooker (Longmans). — Lepidopteraof
the British Isles: C. G. Barrett. Vol. 2 (L. Reeve). — Hydraulic Motors:
G. R. Bodmer, 2nd edition (Whittaker)..— Queen's College, Galway. Calen-
dar for 1894-95 (Dublin, PonsonbyJ. — Stephen's Catechism of Practical
.\griculture, new edition (Blackwood). — A Handbook to the Carnivora.
Part I : Cats, Civets, and Mongooses : R. Lydekker (Allen). — Science
Readers: V. T. Murche. Books i, 2, 3 (Macmilian).

Pamphlets. — Bacteriological 'I'cst of the Purity of Water: E. H.
Hankin (.\gra). — The Early Relations between Maryland and Virginia :
J. H. L.atanc (Batlimore). — Report of the Rugby School Natural History
Society, 1S94 (Rugby). — Report of the .Manchester Museum, Owens Col-
lege, 1894 (Manchester).

Serials. — Engineering Magazine, April (Tucker). — Journal of the Royal
Statistical Society. March (btanford). — Journal of the CI emical Scciely,
April (Gurney). — Journal of the Federated Institutes of Brewing, Nos. i
and 2 (Harrison). — American Jcurnal of Scierce, April (New Haven). —
Journal of the Sanitary Institute, April (Stanford).— Science Prociess, April
(Scientific Press, Ltd.) — Bulletins de la Soci^tC d'Anlhropolocie de Paris,
No. 9, 1894 (Paris, Masson). — Astrophysical JoLmal. April (Chicago).

CONTENTS PAGE

The Experimental Physiology of Plants. By

D H. S 577

Mussel Culture. By W. A. H 578

Historical Epidemiology 579

Our Book Sbelf:—

Helm : " Grundziige der mathematischen Chemie." —

J. W. R 580

Djakonow und W. Lermantoff: " Die Bearbeitung

des Glases auf dem Blasetische " 580

Slingo and Brooker: "Problems and Solutions in

Elementary Electricity and Magnetism " 580

"Qualitative Chemical Analysis of Inorganic Sub-
stances" 5^

Letters to the Editor: —

Prof. Bolizmann's Letter on the Kinetic Theory of
Gases. — Edward P. Culverwell ; Prof. Ludwig

Boltzmann ... 581

The Recent Auroral Phenomenon. (Illustrated.) —

Jas. G. Richmond 581

The Age of the Earth. By Prof. John Perry,

F.R.S 582

The Seismological Observatory destroyed at

Tokio. {/iliislralcJ.) 585

Terrestrial Helium ? By J. Norman Lockyer, C.B.,

F.R.S 586

Notes 586

Our Astronomical Column : —

Lunar River Hcds and Variable Spots 5^9

The Ulua- Violet Spectrum of the Corona 589

Stellar Parallaxes 5^9

The Sun's Place in Nature. IV. (Illuslratcd.) By J.

Norman Lockyer, C.B., F.R.S 590

New Compounds of Phosphorus, Nitrogen, and

Chlorine 592

Biological Work on the Illinois River, (lllus-

iralcd.) . . . ■ 593

The Vaiieties of the Human Species 595

University and Educational Intelligence 598

Societici aiiU Ac>aeiiiie8 599

Diary of S.icicties 600

biuoKK, Pamphlets, and Serials Received 600

ic-

liti'

itif

atioi

NA TURE

60 1

THURSDAY, APRIL 25, 1S95.

CONTROVERSIAL GEOLOGY,
'ollecled Papers on some Controverted Questions of

Geology. By Joseph Prestwich, D.C.L. (Oxon), F.R.S.,

F.G.S., Corr. Inst. France (Acad. Sci.) ; Acad.

R. Lyncei, Rome; Imp. Geol. Inst., Vienna ; Acad.

Roy., Brussels ; Amer. Phil. Soc, Philad. ; &c.

(London : Macmillan and Co., 1895.)

"XiriTH respect to the main facts of Geology, we

V V geologists are in general of one opinion, but
with respect to the explanation of many of those facts,
ve hold very divergent opinions." In these opening words
jf his preface, the author explains and justifies the publi-
ation of this collection of essays. Prof Prestwich's
position, as the acknowledged doyen among British
geologists, demands that these articles— the latest fruits
of his ripe experience — should receive the most thought-
ful consideration from his fellow geologists ; but, quite
apart from the position and authority of their author,
all of the mem:)irs included in this volume are of the
greatest value as contributions to science ; and in reading
them it is difficult to say whether we are more impressed
by the wealth of knowledge or the literary grace which
they display.

The key-no:e of the volume is struck in the first
article, "The Position of Geology — a Chapter on Uni-
formitarianism," published in the Nineteenth Century
of October 1S93 In this short and admirably written
essay, the author clearly defines his own attitude with
respect to the doctrme of uniformity. He credits most
English geologists with a belief in an absolute uniformity
60th in kind and degree, vihWe he and many continental
geologists, who fully accept uniformity in kind, altogether
reject the notion that the actions going on at the present
day can be accepted as measures of the rate of similar
changes in the past. We cannot help thinking, however,
in reading this essay, that the issue is not quite so simple
as the author implies. The strictest uniformitarian would
never maintain that no action that has taken place in past
geological times could possibly have exceeded in violence,
or in the effects produced by it, the phenomena which
we may have happened to have witnessed during that
century or two, in which systematic studies of terrestrial
changes have been carried on. In 1783 a volcano in
Iceland threw out lava having a volume equal to that of
Mont Blanc ; and in 1 8S3, another volcano in the Sunda
Straits projected materials to the height of sixteen miles
into the atmosphere. Now no geologist would maintain
that there could not possibly have occurred, in the long
periods of the past, more violent eruptions than these.
The uniformitarian only asks that in the explanation of
the past we confine ourselves to operations of the same
order of mignitude, as those novv occurring upon the
earth. We shouUl be surely justified, for example, in
asking for very definite evidence that in past times a
single geological eruption had thrown out materials equal
to the volume of the whole .'Mpine chain, or that another
had projected materials to the height of 150 miles. If a
gorge can be shown to have been cut by an existing river
in 1000 years, it would hardly be legitimate to infer that a
NO. 1330, VOL. 51]

similar gorge was cut in ten years by a river of 100 times
the volume, unless at the same time it were shown that
there were very strong reasons for believing that rivers of
the proportions assumed actually existed in the past.

Prof Prestwich puts what he conceives to be the
position of the unifurmitarians in the following simile : —
" What if it were suggested that the brick-built pyramid
of Hawara had been laid brick by brick by a single
workman .' Given time, this would not be beyond the
bounds of possibility. But nature, like the Pharaohs, had
greater forces at her command to do the work better and
more expeditiously than is admitted by the uniformi-
tarians." We cannot accept the parallel as a just one.
Large brick structures are not at the present day erected
by a single bricklayer, and the historian — who is equally
uniformitarian in his practice with the geologist — does
not feel called upon to suggest any such improbable
origin for a pyramid. But if, on the contrary, it were
asserted that the pyramids are so vast that they must
have been erected by a race of beings of larger stature
and greater physical strength than the men of the pre-
sent day, a position would be taken up similar to that of
the opponents of a rational uniformitarianism. The
historian justly asks that before such a view be accepted,
it shall be shown that the work of pyramid-building
could not be performed by ordinary men working in
sufficient numbers for a long period of time. Nor would
the historian be very greatly concerned if it were argued
that by ordinary men such a task of pyramid building
might extend over several reigns, or would even require
centuries for its accomplishment. Every historian, in
fact, takes up the same attitude as the uniformitarian
geologist when he refuses to credit the men of bygone
ages with gigantic stature, prodigious strength, abnormal
wisdom, or extraordinary longevity.

While, however, we demur to the principles and ideas
ascribed by the author of this volume to the uniformi-
tarians, we gladly accept his work as an additional proof,
if such were required, that old-fashioned " catas-
trophism " in geology is now quite extinct. More than
this, we think that the protests and cautions of so
distinguished and able a reasoner as Prof. Prestwich will
render a real service to geology in calling attention to
somewhat unwarrantable assumptions that have been
made by some theorists. With our author's complaint
against what he justly compares io the closure, 3.i applied
by physicists and mathematicians to the legitimate specu-
lations of the geologist, we entirely sympathise. " It
would," as he justly says, " be an unfortunate day for any
science to have free discussion and inquiry barred by
assumed postulates, and not by the ordinary rules of
evidence as established by the facts, however divergent
the conclusions to which those facts lead may be from
the prevailing belief"

The second essay in the volume is a weighty criticism
of the astronomical theory of glacial epochs. The onlv
objection which we think c.in be taken to the essay is
that the author identifies the upholders of this theory
with the uniformitarians. The late Sir Charles Lyel
never accepted the theory of Mr. CroU, and many holding
the strongest uniformitarian views have always main-
tained that geological facts are opposed to any of those

602

NA TURE

[April 25, 1895

explanations of vicissitudes in climate in past geological
times, which are based on astronomical considerations.

In the third article, Prof. Prestwich discusses "the
primitive characters of the flint implements of the chalk
plateau of Kent, with reference to the question of age
and make." The author of this essay, thirty-six years
ago, took a leading part in making known the evidence
in the Somme Valley and elsewhere, which is now uni-
versally accepted as establishing the antiquity of man.
In the essay before us, he insists that, before the times
when men fashioned the beautifully chipped imple-
ments of our river valleys and caves, a still more primi-
tive people employed rough flints as scrapers, just as d id
the recently extinct race of Tasmanians. The beautiful
series of plates accompanying this article will, we think,
carry conviction to the minds of most arch;eoIogists and
geologists, that the existence of such primitive races has
been established by the author. Prof. Prestwich, how-
ever, argues that the antiquity of the men of the river
valleys and caves, and of still more primitive people who
used the flints of the Plateau period, though very great,
was probably less than some theorists have imagined.

The three last articles, " On the Agency of Water in
Volcanic Eruptions," "On the Thickness and Mobility
of the Earth's Crust,' and " On Underground Tempera-
tures,' are well known to all geologists ; but for the
present volume these memoirs have been revised, and
some very important and valuable additions have been
made to them. They will be much more convenient for
purpose of reference than in the journals in which they
originally appeared.

There is one aspect of the work before us to which we
cannot avoid alluding before concluding this notice. All
the articles are controversial, as indicated by the title ;
but the work might fairly be cited as an example of the
spirit in which scientific discussions ought to be carried
on. No geologist, who takes up this work, but will find
cherished ideas reasoned against, or pet notions boldly
assailed. But from beginning to end of the volume, he
will find that no word has been written which is calcu-
lated to give pain to the most sensitive opponent. This
is high praise ; but it is not higher than might have been
anticipated as the due of one who has in a long career
inspired such universal admiration, esteem, and affection
as the successor to the chair of Buckland and Phillips in
the University of Oxford. JOHN W. JUDD.

POPULAR WEATHER FORECASTS.

My IVeather-wise Companion. Presented by B. T.
(Edinburgh and London : William Blackwood and
Sons, 1895.)

DOES " B. T. "stand for Barometer and Thermometer,
the instruments which some people arc foolish
enough to think necessary for forecasting the weather, or
in this simple guise docs modesty shelter itself from too
great' publicity and the evils that popularity brings.'
The connection is curious, but probably accidental, for
the book is free from all scientific technicalities, and the
author would like us to forget that such things existed,
and adopt processes that can be practised by all, with-
out any outlay on cosily apparatus, without elcgraphic
NO. 1330. VOL. 51]

information, and the weariness of preparing synoptic
charts. Herein " B. T." is wise, for he is assured of a mu:h
larger audience, since the instruments with which he
works are in the hands of every one, and no previous
knowledge is required for their use. The sky, the clouds,
the moon, animals, plants, &c., these are the tools ou r
author uses; but even these may at times be a little
inconvenient and diflicult in their application. For
instance, some of us might very well have wished to
know that the winter through which we have just passed
was likely to prove more than ordinarily severe, in order
to take necessary precautions about water-pipes and such-
like necessary evils. Here is the method of test : " If the
mole dig his hole two feet and a half deep [this sounds
like a sum in simple proportion, but such a conclusion
would be premature], expect a very severe winter ; if
two feet deep, not so severe : if one foot deep, a mild
winter." No one would probably care to contradict this;
it may be perfectly true, but then as a rule people do not
go about the country with pickaxe and shovel, looking
for mole-holes, and laboriously and exactly determining
their depth. Such severe exercise would be undertaken
only by a very ardent meteorologist, arid even he might
be discouraged, for the author does not say that the
winter will be severe or otherwise, but only that it may
be expected.

In another respect our author shows much worldly
wisdom. It may be assumed that what the public look
for from the maintenance of Weather Bureaus and
Meteorological Offices, is to know whether it is going to
rain. A forecast that says that the wind will be from
the south-east, possesses little general interest ; what a
man wants to know is whether it be possible to dispense
with an umbrella, or whether one must submit to the
extra care and anxiety the carriage of one entails. It'
may be to some a matter of the keenest excitement to
know whether a depression exists on the coast of Ireland;
while some, again, will even speak disrespectfully of an
anticyclone in Central Europe ; but the " man in the
street •"' will be perfectly satisfied if he can be assured that
the next hour or two will remain fine. Hence the author
wisely concerns himself principally with the signs that
make for rain. This kind of information, as the author
is careful to point out, is welcome alike " to the prince
and peasant, to the anxious hostess who trembles for the
success of her garden-party, to the tinker who seeks the
friendly shelter of a wayside hedge, down to the dandy
in Pall Mall, who hates to carry an umbrella." And on
the subject of this umbrella we think we have some righ t
to complain. He, it would seem, has carried one and
the same umbrella through a period of fifteen years,
carried it, nay used it, amidst aristocratic surroundings,
and occasionally under circumstances likely to test the
constitution of the most carefully constructed ; and yet
w gather that it is still a presentable article, and one
that could be unfurled in Piccadilly with confidence by
the most fastidious. Why could he not have given us
the recipe that preserves to an umbrella such a long life
of usefulness ? This contribution to economics would
have been a valuable testimony to the accuracy of his
conclusions and the keenness of his observation, since it
might be fairly inferred that this protection was not
carried when it was not wanted. But, alas, we have to

April 25, 1895J

NA TURE

60'

ontent ourselves with a collection of rules and portents,
jie belief in which we fondly thought the Education Act
(ind the School Board had utterly abolished. I

' And even here our old friends, when brought out for ]
JUT edification, are not in the form in which they are I
!amiliar,and have been long beloved. Look at the bald-
less of the assertion — " Expect bad weather if cats wash
heir faces and lick their bodies." Contrast it with the
najestic roll of the well known couplet —

Puss on the hearth, with velvet paws,
Sils, wiping o'er her whiskered jaws.

We distinctly feel that we are robbed of something;
:here is such a pleasant jingle in the old rhyme, that it
:arried conviction with it. How disappointing, too, to
De told o nly to expect. We may just mention, in passing,
that this is not the conclusion which we should expect
Ithe average fourth standard boy to draw from witnessing
Ithe operation on the part of " puss." We should expect
that young gentleman to remark that " cat's hair appeared
to be slightly hygroscopic"

Altogether this little book reminds us of those admir-
able compilations in which the theory of whist is .,ome-
times exposed : a vast number of rules is given, which if
one could remember and select at the right time he
would never make a mistake ; but, unfortunately, the com-
binations on which the rules are founded have a knack of
I eluding the unlucky player, and never seem applicable to
the hand in play, with the consequence that in his etForts
to remember some rule, he trumps a thirteenth at an
inopportune moment, and earns the contempt of a long-
suffering partner. In the same manner one can conceive
the city man, armed with this collection of precious and
invaluable rules for determining the weather of the
coming day, debating with himself whether it was last
night or this morning that the sky was red ; did he, while
shaving, see his dog eating grass on the lawn ; and what
is the exact age of the moon — finally getting confused by
the knowledge that the train is nearly due, rashly seizing
his mackintosh and umbrella in the middle of a well-
determined summer anticyclone, and so forfeiting his
hard-earned position of a trustworthy weather prophet
and a man of keenness and nicety of observation.

THE MYCETOZOA.
A Monograph of the Mycetozoa; being a Descriptive
Catalogue of the Species in the British Museum.
Illustrated with seventy-eight plates and fifty-one
woodcuts. By Arthur Lister. (Printed by order of
the Trustees. London : 1894.)

ALTHOUGH this is an official publication of the
Natural History Department of the British Museum,
that part of the title referring thereto is somewhat mis-
i leading, because the author includes everything published
1 belonging to this curious group of organisms, .-^t the
I same time it is not a monograph in the strict sense of the
I word, because the author had no opportunity of examining
I a laige number of the reputed species inhabiting Central
Europe, Scandinavia and North .-Vmerica. Thus, out of
15 species of Badhamia, only 9 came under his observa-
I tion ; of Physarurr., 30 out of 45 ; of Didymium, 8 out
of 17, and so on all through. It is true that he repeats,
NO. 1330, VOL. 51]

in English, the authors' descriptions, and frequently
suggests the affinities of the species in question.

Further, apart from the fact that the book was pub-
lished under the authority of the Tnistees of the British
Museum, and the fact that " ever)- species of which I
have given the characters can be examined either in
bulk, or as a mounted object in the British Museum,"
it might with equal propriety have been entitled a
descriptive catalogue of Mr. Lister's own herbarium, or of
the Kew herbarium, because, as he acknowledges, he had
full use of the Kew set, including all Berkeley's numerous
types.

However, this does not aSect the character and quality
of the work. Mr. Listers previous contributions to the
literature of these curious and debatable organisms were
a sufficient guarantee of good and really original work,
and he has no doubt met all reasonable expectations on
this point, Indeed few works have recently been issued
embodying so much original research. The ^fycetozca,
as limited by De Bary, Rostafinski, Lister, and others, are
essentially the same as the Myxogastres of Fries and the
Myxomycetes of Wallroth. The first name was substi-
tuted for the older ones because it was discovered that
the spores, instead of producing a mycelium as in fungi,
gave birth to swarm-cells which coalesce to form a
Plasmodium ; thus indicating a relationship with the
lower forms of animal life. Mr. Lister adopts this
designation, and defines the group as follows : —

" A spore pro\ided with a firm wall produces on germin-
ation an amceboid swarm-cell which soon acquires a
flagellum. The sv<-arm-cells multiply by division and
subsequently coalesce to form a Plasmodium which
exhibits a rhythmic streaming. The plasmodium gives
rise to fruits which consist of supporting structures
and spores ; in the Endosporea, these have the form
of sporangia, each having a wall within which the free
spores are de%'eloped. .A. capillitium or system of
threads forming a scaffolding among the spores is
present in most genera. In the Exosporea the fruits
consist of sporophores bearing numerous spores on
their surface."

He then proceeds to describe in detail the develop-
ment aud various stages, in fact the life history of these
organisms, and this he has done in a simple and lucid style
worthy of all admiration. The movemsnts of the swarm-
cells — creeping and dancing movements — are most inter-
esting, as well as that of the plasmodium, or ag^egation
of cells ; but the feeding of the swarm-cells is most
exciting. Mr. Lister had pre\-iously published accounts
of his o bsen-ations of the ingestion of food-material by
the Mycetozoa in this stage of their development ; yet a
sh rt extract relating to this process is not out of
place : —

" If baaeria are introduced into a cultivation of
swarm-cells on the stage of the microscope, they are seen
to be laid hold of by the pseudopodia and drawn into
the body of the swarm-cells, where they are enclosed in
a digestive vacuole. Several bacteria are bnught in
turn to the same chamber, or fresh captures are conveyed
into one or more additional vacuoles. The protrusion
of pseudopodia usually ceases after such ingestion, and
that part of the swarm-cells takes a rounded form. In
the course of an hour or two the bacteria are assimilated
and the digestive vacuoles disappear. Unicellular algae
and inorganic matter are sometimes taken in, which after
a time are again discharged. Both ingress and egress
are observed to take place only at the posterior end."

0O4

NATURE

[April 25, 1895

It should te explained that an ordinary swarm-cell in
the feeding stage is an elongated body tapering at one
end into a long cilium or lash, and more or less truncated
at the end with several short cilia, the so-called pseudo-
podia. Within the body of the cell is a nucleus and
several vacuoles.

With regard to hybrids between the plasmodia of
different species, Mr. Lister is in accord with De Bary,
and doubts the accuracy of Mr. Massee's observations.

-Another point of great interest is the very wide geo-
graphical distribution of most of the species ; and the
main characters, Mr. Lister states, are remarkably con-
stant in specimens gathered in all parts of the world.
Mr. Lister gives a number of instances in which speci-
mens obtained from Europe, India, and North and South
America are identical in the most minute microscopic
detail. But there are exceptions, in which individuals
of the same species from tropical and temperate regions
exhibit differences in form ; the tropical ones being of
more elegant growth.

In his description of the sclerotium, or resting stage,
of the Plasmodia, Mr. Lister states that the sclerotium
of Badhamia ulricularis can be revived, after preser-
vation in a dry state for three years, by being placed in
water. He also gives the results of a number of in-
teresting experiments on the vitality of various other
Mycctozoa. Altogether Mr. Lister's "Introduction" is
most instructive, and his descriptions are so clear, that
this book should go far to popularise the study of these
organisms. The plates, which are collotype repro-
ductions of water-colour drawings, are very good, but
much of the beauty of the originals is lost in the process.
It is a pity that they were not reproduced in colour. .And
this leads one to ask why the coloured figures in Massee's
"Monograph" are not cited. It is true there are
references to the pages of that work, which would lead
one to the figures, if one knew of their existence. It is
disappointing, too, that the author has attempted no
review of the previously existing literature, and has not
even thought it necessary to devote two or three pages to
bibliography. These omissions are all the more sur-
prising when one considers the facilities the author
enjoyed in the prosecution of his studies.

A NEW WORK ON DYEING.
La Pratique du Teinturier. By Jules Gar(;on. Two vols.
Pp. 148 and 391. (Paris: Gauthier-Villars et Fils,
1893 and 1894.)

THE art of dyeing has in recent years developed
so rapidly — having been practically revolutionised
and to a large extent remodelled during the last thirty
years — that text-books and works of reference dealing
with the subject rapidly become defective. We are
therefore always glad to welcome any new work which, as
far as possible, epitomises the information up to date.

The great energy and enterprise exhibited by the large
firms of colour manufacturers in such a marked degree,
has, moreover, a tendency to develop what may be
distinguished as the art of dyeing, more rapidly than the
handicraft. It is, therefore, pleasant to note that, as
an engineer, the author of the book under review fully
appreciates the importance of the manipulative and

NO, 1330, VOU 51]

mechanical side of the subject, and gives a lucid de-
scription of many of the recently introduced appliances.
The plan of the book ditTers somewhat from that
usually found in works on dyeing. There i?, for instance,
no description of the character and properties of the
textile fibres or of the colouring matters ; but the various
theories which have been put forward to account for
dyeing processes, although of necessity based on such
facts, are discussed at considerable length, .\gain,
chemistry, as expressed by symbols and equations, i^
conspicuous by its absence ; but a lengthy chapter on
the elements of chromatics is introduced. However, as
the book is|as yet incomplete (a third volume being
in course of preparation), it is too early to definitely
consider these as omissions.

Volume i. contains a very short and sketchy historical
introduction, followed by a few notes regarding the
relative advantage of the natural and artificial dye-stuffs.
A classification of the colouring matters— following the
usual lines — is then given, with some very general note'
with regard to the application of each class of colour-
to the various fibres. This section of the book might
certainly have been considerably extended with advan-
tage, since undue compression necessitates a too-free
generalisation and an inadequate explanation of the facts
For instance, it is not suflicient to state (p. 13) th.it the
acid used in dyeing with sulphonic acid colouring matter-
(always employed as salts) serves to liberate the fret
colour acid. This is really a very secondary action
requiring only a small fraction of the amount of aciil
used, the principal function of which is to prepare tht
wool for combination with the dye.

The methods of dyeing linen, jute, China grass, feathers
&c., are also noticed, a useful bibliography on the dyeing
of feathers being introduced. This commendable feature
is also noticed in several other sections of the book.

The second part of the first volume is concerned with
the actual processes of scouting, dyeing, and finishing
The space allotted to this is again very small ; the de-
scription of the bleaching of cotton and of wool occupy-
ing less than half a page. Some useful hints are, how-
ever, given with respect to the choice of dye-stuffs, the
storing, dissolving and examination of colours, the causes
of defects, &c.

M. Gar(;on devotes consider.able attention to the ijues-
tion of the fastness of colours, and discusses the infiuence
in respect to this property, of the nature of the fibre and
the colouring matter employed, of the method of apply •
ing the colour, of the character of the light and the
atmospheric conditions. With regard to the relationship
between the chemical con-titution of the colourinj;
matter and its behaviour on exposure to light, it is noted
that although most members of any particular j,'roup
act in a similar manner, a slight difference in constitution
is sometimes sufficient to cause a great difference inJ
permanence ; thus, although most of the anthracene
colours are " fast," and all the triphenylmelhane deriva-i|
tives "fugitive," pallein is much more resistant than the
closely allied eosin dyes, and by simply sulphonating
indigotin, one of the most permanent dyes is changed
into a very fugitive colour. It may be added thai
derivatives of methyl anthracene appear to be com
paratively fugitive to light.

April 25, 1895]

NATURE

605

It is thus not safe to put forward any assumptions,
based either upon chemical relationship or similarity of
general properties, concerning the behaviour of colouring
matters in this respect ; and therefore, recognising the
\alue of a systematic examination, the author gives, at
considerable length, the results obtained in recent years
by Hummel.

When discussing certain experiments in which arc
lamps have been employed as the source of illumination,
it is stated that the electric light behaves similarly, but
less energetically, than sunlight ; the average bleaching
action of sunlight having been estimated at 30 per
cent, of its total luminosity, while that of the electric arc
is only about 6 per cent.

The third section of the first volume deals with
oper.-itions subsequent to dyeing, such as soaping, mill-
ing, steaming, &c. It is very short, extending only to
four pages. Two appendices, the first dealing iwith
theories of dyeing, and the second with the elements of
chromatics, are added, and the volume ends with a very
complete bibliography of the works on dyeing published
during the last 100 years.

The second volume is devoted to a description of the
machinery used in dyeing and allied processes, a very
Urge space, equal in fact to the whole of the first
volume, being occupied by the subject of water purifica-
tion ; which, although of great importance to the dyer,
certamly receives undue prominence. The great fault
of the work, as a whole, is indeed a certain lack of pro-
])ortion ; many essential points receiving scant attention,
while valuable space is occupied to smaller advantage
by long descriptions of less important subjects — such, for
instance, as the Westinghouse air-pump. Nevertheless,
the book should prove a valuable reference work for
managers of works, or students of dyeing, to whom it
can be heartily recommended.

Walter M. G.^rdner.

OUR BOOK SHELF.

The Fauna of British India, including Ceylon and
Burma. Published under the authority of the Secre-
tary of State for India in Council. Edited by W. T.
Bianford. " Moths," Vol. ui. By G. F. Hampson.
(London : Taylor and Francis, 1895.)

We have already noticed the two preceding volumes of
this work in some detail ; and it is therefore unnecessary
to say more respecting the general execution of this
volume than that the letterpress is arranged in a similar
manner, and that the execution of the woodcuts is equally
good. The present volume includes the last two sub-
families of the yV6'tV«/(/«-',the/'('<vy//>;(r, and \}i\i.I)eUoidinic,
and one or two small families of the Ge,iinetridcr. Re-
specting the Dcltoidimc, Mr. Hampson remarks: "It
exhibits a gradual development from forms with straight
palpi fringed with hairs above, such as llypcna, which
is closely allied to the Sarrothripime, and to the ances-
tors of the Noctuida and Nolina, through forms with
oblique palpi, to a group possessing palpi of an ex-
tremely curved sickle-shaped type; from this group
arose the stouter-built, more typically noctuiform and
nocturnal Focillina- and (Juadri/iiKi-." We seriously
doubt the advisability of speaking in such a positive
manner on questions which cannot, in the present state
of our knowledge, be anything more than very doubtful
inductions, at the best.

NO. 1330, VOL. 51]

After the Nocluidce, Mr. Hampson places the families
Epicopiidce, Urantida:, hpiplemida:, and Ceoinetridie,
for the last of which he has followed Mr. Meyrick's
classification. Under the Uraniidcc he includes a con-
siderable number of genera, most of which, except
Nyctaleinon, were included by previous authors in the
Microniidce, and other families ot Geometrida. A fourth
volume is to conclude the i ndian Macro-Lepidoptera, and
to contain the Pyralidce and a supplement ; and we are
glad to learn that Lord VValsingham is working at the
Micro-Lepidoptera of India.

Mr. Hampson speaks of the difficulty of the sub-family
Boarmiince in the Ueoinetridce j and under the genus
Boarinia itself he includes no less than eighty-five species,
divided into several sections, to some of which sub-generic
names are applied. As, however, no less than twenty-
eight generic names are included as synonyms of Boarmia,
we think it would have been better to have treated some,
at least, as provisionally entitled to generic rank. And
this leads us to a consideration of the most serious de-
fect in all Mr. Hampson's work, which has already been
pointed out in more than one quarter. He is too
much inclined to place forms together as varieties, and
then to treat them as actual synonyms. It is true that
in a few instances in the present volume he discriminates
between named varieties ; but far more frequently he
gives a description of a species in a lew lines, preceded
by a string o( hall-a dozen or more names, without any
hmt of how far these names represent distinct forms, or
which names represent his idea of the species he is de-
scribing, even when he nonces that the species is vari-
able. While making allowance for exigencies of space,
this is hardly fair to those who will use his books ; for
even if we assume that Mr. Hampson is always correct
in his views as to which forms are entitled to specific
rank, and which are only to be regarded as varieties, it is
not to be supposed that every one will take exactly the
same view ot a doubtful case ; and we greatly fear that
if an entomologist meets with an insect which does not
correspond with the description of a species given by Mr.
Hampson, he will at once describe it as new, and, in many
cases, redescribe one of the forms which Mr. Hampson
has rejected, with a light heart, as a mere synonym.

Apart from this serious delect, we can recommend the
book as a most useful and, indeed, quite indispensable
manual for all who are interested in East Indian Moths.

W. F. KlRBV.

LETTERS TO THE EDITOR.

The Editor ,lots not hold himself responsible for opinions ex-
pressed by his correspondents. Neither can he undertake
to return^ or Co correspond with the writers of rejected
manuscripts intended for this or any other part of NaTURK.
Xo notice is taken of anonymous communications.]

The Origin of the Cultivated Cineraria.

Rktukning from abroad, I have just seen Mr. Dyer's letter
in Natuke, Maich 14. Of the matters there ireated I ask
leave now lo deal wiih one only, that numbered (iS). This is
a point of (aci — the origin ol the culuvaled Cineraria. At a
meeting of ihe Royal .'society, on Kebjuary 28, Mr. Uyer
exhibited a specimen of Ctiuraria cruenta from the Canaries,
side by side with a plant of the common cullivated form. With
the object uf minimising the value of "sports" in evoluiion,
this exhibition was made lo illustiaie what can be done " by the
gradual accumulation ^f small varialions." Mr. D)cr slated,
it 1 rightly understood him, first, that ol the two forms exhibited,
the one had been produced from the o;her ; secondly, that, as
far as is known, this process ol evolution had been accomplished
by the gradual accumulation of small variations, and not by the
selection of "sports" or seedlings presenting notable and
striking variations. That in the case of a plant much modi-
tied by gardeners in recent limes such a history would be highly
unusual, Mr. Dyer will, I think, admit.

6o6

NA TURE

[April 25, 1895

Doabting this account, and searching records of the early
cnltare of the Cineraria for my own satisfaction, I found a good
deal of miscellaneous information on the subject. The history
is not yet quite complete ; but as Mr. Dyer's account has now
appeared in print, the following notes may be of use.

In the ordinary manuals (e.g. Burbidge, Propagation &c.,
1S77, p. 250) it is said that the florists' Cinerarias are hybrids,
obtained by crossing and recrossing several species of Ctnerariii
(or more strictly Sencn'o). As to the exact parentage, there is
not entire certainty. Burbidge gives C. crtunta, aurila aiid
lanata as the parents. Other writers mention C. maderensis,
multifiora, tiissilagitiis and topulifolia as having contributed
(cp. four, d'hort. Gand, ii. 1846, pi 231). General statements
of a like nature are made by many. For the account given by
Mr. Dyer I find no authority except one, an article by Rolfe
{Card. Chron. iSSS (i), p. 653). Here C. criieiila is given as
the sole parent, and a figure of this species raised at Kew, from
wild seed, is shown beside two extreme flowers of the modern
type. Excepting this statement, it seems agreed that the
species originally concerned are at least four : crucnta, aiirtia,
popiilifotia and lanata. The first three have comparatively
small flowers in corymbs or cymes. Those of cnienta, intro-
duced from Canary by Masson to Kew in 1777. '^''^ purple.
This species was originally described from Teneiifl'e by
L'Htritier, Sert. Angl. 1788, pi. 33, and is figured Bot. Mag.
t. 406, and elsewhere. The lower surface of the leaves is
purplish. The petioles have auricular expansions. C. aurita,
sent to Kew from Madeira 1790, figured by L'lluritier, pi. 31,
and Bot. Mag. t. 17S6, is a somewhat different plant, of more
slender habit, said to be more akin to populilolia. The flovyers
are purple. Ray-florets few and irregular. Petiolar expansions
variable, mostly much smaller than in crucnta. C. populiJoUa
L. Her., Canaries, brought by Masson from Teneriffe 1780,
is a form with yellow flowers. C. lanata, L'Hcr. pi. 30, and
Bot. Mag. t. 53, is a plant very different from any of the others.
It bears large purple flowers, some two inches across, only one
to a peduncle. The leaves are cordatesubrotund and sept-
angular, and woolly underneath. L'Huriiier gives it as from
Teneriffe. The Bot. .Mag. wrongly says it had been introduced
from Africa (perhaps confusing with lanosa, DC. = lanata
Thunb.). The large flowers and peculiar leaves at once dis-
tinguish this species from the rest.

It should be added that populifolia in its native state showed
considerable diversity in the forms of its leaves, three varieties
being specified by Decandolle, Prodr. vi. p. 409. A natural
variety of the .same species with -.i'liili flowers was brought from
Teneriffe by Webb. This is the S. leuiantlius DC. It is
figured in Flor. Cab. i. p. 73, from a specimen grown in Bir-
mingham Botanic Garden. \% to these species, references to
further information may be found in Decandolle, Prodr., and in
Webb, Phytogr. Canar., &c.

These four species with others were at the beginning of this
century pretty generally distributed in greenhouses in England,
France, and Germany. They are enumerated in most of the
horticultural treatises of the period, with directions for their
propagation. C. lanata was thought the best. " It far exceeds
all others cultivated here in the beauty of its flowers. ... It is
valuable on account of its hardiness, its readiness to flower, and
the facility with which it may be propagated." Kees' Cycl.
oj Arts and Sei. viii. i8ig. Others speak to like effect.

The first mention I have found of any distinct garden form is
that of Willdenow, who in " Enum. PI. Berol." 1809, p. S93,
gives C. hybrida, saying that this plant is grown in gardens
under the name of C. cruenta, but that it in reality differs much
(rom the latter, and has flowers almost like those of C. lanata.

Between 1820 and 1830 definite eff'orts were made to improve
the Cineraria. The first published is that of Bouchc. Writing in
the " Verh. zur Belord. d. 'iartenbauer, 15erl.,"i. 1824, p. 139, he
says that having grown C, lanata 1,'ilcr., C. cruenta L'lltr.,
and C. hybrida Willd., and noticed that the first two seeded
freely, it occurred to him to try to raise varieties or sports
\Spielarten), and at the same lime to test the distinctness of
these species. His seedlings flowered in the following year.
Those (rom C. cruenta had the flowers rose-red, except one which
wa» quite white, the flowers of the parent being dark red. The
seedlings from C. hybrida varied so much that they might be
mistaken for separate species. Ilis words are as follows: —
" Untcr dcnen von dcr Cin. hybrida zeichnetcn sich liesonders
funf Abanderungen aus, wclche eine ganz eigcnthiimliches
Anschcn bekommcn habco, und Icicht von Botanikcrn, dcncn

die Entstehungsart derselben nicht bekannt ist, fiir neae, noch
unbeschriebene Arten dieser Gattung gehilten werden
kdnnlen.'' His description follows. In particular, the foliage
had varied greatly from the parent form, somewhat resembling
lanata, suggesting to Bouche that there may have been
hybridisation with that species.

About the same time Mr. Drammond, then Curat'jr of the
Botanic Garden, Cork, published a paper in the CirJ. Mag. ii.
1S27, p. 153. He says that Cinerarias are favourites with him,
especially cruenta, "(or be>ides the great be,auty an! variety
in the flowers, its fine purple blossom • form a beautiful con-
trast, &c." " We seldom see it cultivated to the extent it merits.
The following account of the method I have followed fjr some
years of growing this plant. . . miy turn the attention of your
readers to the cultivation of the C cru-.nla, the effects of which
wiU, in all probability, be the production of fine double and single
varieties of different colours, as it sports greatly from seed.
[Italics are mine.] Except in cases when it becomes desirable
to preserve any particular variety for its superior be.auty, I
prefer raising the C. cruenta from seeds. . . . Care should be
taken to select the finest varieties, and those that produce
the largest and finest heads or corymbs of flowers. " "The
other greenhouse species I cultivate are lanata, hybrida,
gei/olia and amelloides. These I increase by cuttings, Sec."

It happens that in the same year (1827) of the Card. Mag,
p. 446, there is a reference to Bouche's paper. Not improbably
Drunimond may have read the latter, for in Loudon's Ladies' Mag.
of Card. 1842, p. Ill, I find this passage :" Most of the purple.
Cinerarias are varieties or hybrids of C. cruenta. ... It was
long a favourite in greenhouses, and was generally propagated
by dividing the roots; but about 1S27, Mr. Drummond,
Curator of the Botanic G.irden in Cork, having raised it from
seed, and found the seedlings vary considerably, conceived the
idea of hybridising it with C. lanata, C. geifolia and C. amel-
loides, Ihe trials, however, with C, geifolia [a true Cape
Cineraria] and C. {Agath.ca] amelloides do not appear to have
succeeded ; but between C. cruenta and C. lanata some hand-
some hybrids were raised. Since that time numerous experi-
ments have been made and hybrids have been raised, &c." .\
summary follows.

Soon after this a number of definite seedlings or "sports"
came into existence. Of some of these there are good records.
I will mention four which are represented by good coloured
plates. C. watcrhousiana is said to have been a hybrid, the
result of the seed of C. tussilaginis, fertilised by the pollen of
crucnta (Pa.xton's .'ifag. of Bot. iv. 1838, p. 43, and Ladies'
Mag. i.e.). In general appearance it rather resembled tussila-
ginis (one of I.'Hcritier's species which had died out, and was
introduced again in 1832 by Webb. See Bot, Mag, t. 3215.)
This must have been a very fine plant. It had large r<ri/flower3,
about two and a half inches across, with long narrow ray-
florets something like lanata.

The next case I shall take is a plant which first flowered iiv
a garden near Belfast, called var. cyanophthalmus in Bot, Mag.
1840, t. 3827. It had long white rays and a blue disc. Sir
W. J. Hooker says of it : " Notwithstanding the very unusual
colour of the flowers for one of the Composilrc, 1 have little
hesitation in referring it to . . . the old C, lanata of our
gardens. The foliage is the same, and the structure of the
flowers ; but the colour of the blossoms is very different, and
in our variety of a most unusual character." He tlien recalU
Dccandolle's well-known remark \\\a\ yellow in Composila- may
vary to red or white, but not to lilue, and, on the other hand, thai
blue may vary to red or white, but never into yellow. lie .idds :
" Not only in our plant is the lilac-coloured r.iy ol the flower
changed to white, and the deep lilac or blood-red purple of the
ray [disc] changed to a very bright blue, but the stigmas, which
are deep orange in the original stock, are also intensely blue,
and the anthers are purple-black."

Another seedling of a very different type, famous in its day,
was webberiana. It was figured in J'axt, .Mag. Bot. ix. 1842,
p. 125. The flowers were of a deep blue, the rays being short
and wide, comp.ared to those of watcrhousiana, for example.
"It was raised from seed ripened promiscuously on a number
of plants of v.irious kinds blooming together, \.c." In the
Card. Chron. 1842, it was advertised at loj. 6d. a plant.

Another sport, pinkish and white, is figured in the /''otanist,
V. 1841, No. 215. " It came up accidentally, some years ago,
from self-sown seeds, in one of the pots of the greenhouse, so
that I cannot say anything certain about its parentage." The

NO. 1330, VOL. 51]

April 25, 1895J

NATURE

607

writer conjectures it to be a iiybrid between lanata and populi-
'olia, var. leucanthus.

If any one will look at the plates to which I have referred,
he may satisfy himself of the astonishing diversity of these
forms. In GarJ. Ma^. 1839, p. 430, is an early record of the
appearance of the new seedlings at shows. At the Caledonian
Horticultural Show, the Cinerarias " were very brilliant, and
partook of novelty." The names of the seedlings successful,
including -jiaterhoiisiana, are given. At the beginning of the
forties the named kinds became very numerous, and were at
first offered at high prices in the trade advertisements. Hen-
derson and Ivery were the two chief English cultivators at that
time.

During this period, 1830-1840, the progress was very rapid,
and there can be no doubt that the florists' Cinerarias came into
existence within some ten or twelve years. Such a plate as that
in Jour, d'harl. Gand, 1846, shows the ordinary kinds much
as we know them. Froni those plants up to the perfected plants
of ten years ago, the change was undoubtedly slow and gradual.
The alterations have consisted chiefly in incre.ise in size and
symmetry of the flower, and in promotion of compactness of
habit (see, e.g., Glenny, Ann. of Hort. 1850, p. 37, also Card.
Chron. 1S79 (i), p. 532).

The next point is of some interest. As compared with other
" improved " herbaceous plants, the Ciner.iria is a little peculiar
in the fact that it is now generally raised from seed. This is
done partly to ensure that the plants shall not be overgrown,
and partly to avoid green fly, a pest to which these plants are
specially liable. In consequence of this, the old " named"
kinds, that is to say, kinds propagated by ase.\ual methods,
went out of fashion, though till lately they still had supporters.
It was found that seeds of good strains could be fairly relied on
— not, of course, to reproduce the form of their particular parents,
but to give fine plants. For instance, Henderson, Scot. GarJ.
i. 1852, p. 22, says : "in raising seedlings you should select
three or four dwarf varieties, which number is quite sufficient to
produce all the different colours." In Card. Chron. 1887(1),
p. 549, are some interesting particulars of the methods used by
Mr. James, to whom the later improvement of the plant in
Kngland is largely due. The plants of each colour are grouped
in blocks, and the bees are freely admitted to the houses. It is
not found necessary to separate the plants further, and in saving
seed all the colours are mixed together. In ihe case of the
Cineraria therefore, as in that of Calceolaria-, Begonias, and
other plants much grown from seed, it is desirable not only to
create a fine variety of which the stock can at once be multi-
plied asexually, but also to raise a good strain of which the
seedlings come fairly true. The latter process may undoubtedly
often take time.

Even in recent times a "sport" has been recorded. In
Card. Chron. 1880 (i), p. 277, it is stated that Mr. James
" has succeeded in obtaining a new ' break ' that promises to
be the forerunner of another host of new flowers. The colours
(if the flower do not shade off into one another, as is usually the
case, but are arranged in bold and well-defined belts. . . . We
understand that it flowered for the first time last season, and
that it has reproduced itself from seed." A figure is given.

To these particulars might be added many more, relating to
the origin of double vaiieties, variations in the foliage, and other
matters. The foregoing notes of the history must, I think be
taken to show (i) that the modern Cinerarias arose as hybrids
derived from several very distinct species ; (2) that the hybrid
seedlings were from the first highly variable ; (3) that "sports "
f an extreme kind appeared after hybridisation in the early
years of the "improvement" of these plants; (4) that the
subsequent perfection of the form, size and habit has proceeded
by a slow process of selection. Mr. Dyer's statement that the
modern Cinerarias have been evolved from the wild C. criienia
"by the gradual accumulation of small variations " is therefore,
in my judgment, misleading, for this statement neglects two
chief factors in the evolution of the Cineraria, namely, hybridisa-
tion and subsequent " sporting."

I have ventured to deal with this case because it seems to be
generally supposed by those not .acquainted with the facts, that
the origin of the modern florists' flowers has in general been
very gradual. As a matter of fact it would, I believe, be more
true to say that the new departures have in general been at
first very rapid, subsequent improvement being commonly slow.
"Sporting," usually after hybridisation, has been the chief
factor in the production of these new developments, just as in

VO. 1330, VOL. 51]

the case of the Cineraria. To speak of no more, I may refer
to the new forms of Begonia, of Gladiolus, and of Erica now
so familiar. With what special propriety the Cineraria was
chosen by Mr. Dyer to support his contention is not evident
to me.

Whether any of these sports exhibit the phenomenon of organic
stability I cannot now discuss. W. Bateson.

St. John's College, Cambridge, April 17.

The Age of the Earth.

In Dr. Hobson's letter on this subject, he confuses the argu-
ment by the introduction of a new factor (never alluded to in
the formerdiscus5ion,or in my theory as stated in "Island Life"),
the bulk or volume of the matter deposited. This has nothing
whatever to do with the practical problem, because it is
admittedly impossible to form<j»y estimate of the total bulk of
all the stratified rocks of the earth during all geological time ;
while it i> equally impossible to form any estimate of the total
bulk of the denuded matter, since we have no clue whatever to
the number of times the same areas have been again and again
denuded. But the maximum thickness of the same rocks,
compared with the average rate of denudation, and the co-
incident maximum rate of deposition, do furnish materials for
an estimate, since they can all be approximately determined
from actual observation ; and the result is what I have given. If
Dr. Hobson had referred to Ihe former discussion he would have
avoided imputing to me "fallacies " which I never made. I never
Slid a word about " equal bulks " of material being deposited in
less time than they were denuded. But, as the only available
data are those of thickness, not bulk, then it is clear that, if the
area of deposition is one-nineteenth of Ihe area of denudation, Ihe
rale of deposition of a known thickness of rocks will be nineteen
times as great as the known rate of denudation. It was neces-
sary for me to point this out when first discussing the subject,
because one eminent writer had made the rate of deposition less
than the rate of denudation, because the water-area is greater
than the land-area of the globe ; while an eminent geologist
has quite recently taken the rates of denudation and deposition
as being equal. If, however, the area of deposition is very
much /«i than the area of denudation, which is now admitted
to be the fact, then the rate of deposition per foot of thickness
will tie many times greater than the rale of denudation.

I should not have thought it necessary again to state this very
obvious conclusion, had not Prof. SoUas, while so clearly point-
ing out Dr. Hobson's misconception as to the area over which
the maximum thickness of the strata extended, omitted to refer
to the confusion he has now for the first time introduced into
the problem, by references to the l>ulk or volume of the sedi-
mentary rocks, a factor which all previous writers have seen to
be wholly beyond even an approximate determination.

Alfred R. Wallace.

So little is really known about the earth's age that any addi-
tional mode of approximating toil, however rough, may possess
some value. The following method of finding a lower limit is,
with one or two alterations, the same as that given in a paper
in the Geological Magazine for 1887 (p. 348). It depends, not
on ihe rate of denudation, but on the rate of subsidence within
the area of sedimentation.

Part of the sediment brought down by a river is used for
keeping the surface of the delta close to the level of the sea ;
and the fact that the deposits formed from it are generally shal-
low-water deposits, shows that the amount of sediment is, as a
rule, sufficient or more than sufficient for the purfwse. The
remainder of the sediment is carried out seawards, and enlarges
the delta laterally.

If there were no surplus sediment, it is evident that the mean
rate of subsidence over the delta would be obtained by dividing
the volume of the sediment brought down annually by the
river by the area of the delta. But if there be an excess of
sediment, then the same quotient will give a value greater than
the mean rate of subsidence, for only part of the sediment is
used for keeping the delta-surface in shallow water. In the
case of the Mississippi, the amount of sediment brought down
annually is 7,459,267,200 cubic feet, and the area of Ihe delta
12,300 square miles, or 342,204,320,000 square feet ; so that
the mean rate of subsidence is not greater than ,',; of a foot per
year, or 218 feel per century.

Prof. Sollas estimates the total maximum thickness of the
different layers of sediment since the beginning of Cambrian

6o8

NA TURE

[April 25, 1895

times at 164,000 feet (Nature, vol. li. p. 534). If these layers
lapered oflF uniformly in eiiher direction Irom the region of
maximam deposit, the total mean thickness would be half this,
or 82,000 feet ; and if the mean rate of subsidence were never
greater than 2"lS feet per century, rhe total time required for
the accumulation of Cambrian and post-Cambrian rocks would
be not less than 3J millions of years. But there may have been
long unknown gaps in the process of their accumulation ; the
outer margin of the deposits may have extended far beyond the
area of subsidence, and the mean rate of sub>idence may have
been at all times considerably less than the upper limit given
above. On these accounts, as well as on others that might be
mentioned, it seems possible that much more than 3I million
years has elapsed since the beginning of the Cambtian
period.

Birmingham, April S. C. Davison.

The Burmese Chipped Flints Pliocene not Miocene.

I.v the Geological Magazine for November of last year, p.
525, is a review by Prof. T. Rupert Jones, of the important
paper, published in the Kaords of the Geological Survey of
Itiiiia, by Dr. Fritz Noetling, the Palaeontologist of the Survey,
" On the occurrence of Chipped (?) Flinis in the Upper
Miocene of Burma." Another paper, by Prof. T. R. Jones, on
" Miocene Man in India," appeared in Natural Science for the
same month.

From the fact that the mammals Rhinoceros ferimensis and
Hipfarion antelopinum, of which bones were found associated
with the flint chips, have only been found in India in Pliocene
beds, and from a slight acquaintance, gained, it is true, more
than ihirty years ago, with the Burmese strata in which Dr.
Noelling's most interesting discovery was maiie, I felt assured
that there must be some error in believing that the flint chips
occurred in Miocene deposits, and I wrote to Dr. Noetling on
the subject. I have just heard from him in reply. In a letter
from Upper Burma of .March 11, he tells me he has now defi-
nitely ascertained that the bed containing the chipped flints is
Pliocene.

Further particulars will, I hope, be published before long by
Dr. Noetling ; and I should not have written on the subject but
that a serious error is caused by its being supposed that
" .Miocene Man " has been shown to have exi^led in India, and
it is desirable that this error should be corrected without delay.
The importance of the discovery is in no way diminished by
the correction of the geological date to which the flint-bearing
stratum is referred. W. T. IJlanford.

April 17.

The Mandrake.

With regard to Prof. Veth's exhaustive account of the
mandrake (referred to in Nature of April 11, p. S73)>
it may be useful to students of folklore to call iheir
attention to the occurrence in the Chinese literature
of a similar superstition, wherein Phytolacca acinosa (Shang-
luh) takes the place of Mandragora officimirum. Sie
Tsai-Kang's " Wu-tsah-tsu," written about 1610 (Japanese
edition, 1661, tome x. p. 41), contains the following passage : —
" The Shang-luh grows on the ground beneath which dead man
lies ; hence its root is mostly shaped like a man.' ... In a
calm night when nobody is about, the collector, offering the
owl's flesh roasted with oil, propitiates the spirit of the plant
until /^nwya/uj crowd about the latter; then the root is dug
out, brought home and prepared with magic paper for a week ;
thus it is made capable of speech. This plant is surnamcd
' Ye-hu ' (1.^. Night Cry) on account of its demoniacal nature. -'
There are two varieties of it : the while one is used for medi-
cine ; the red one commands evil spirits, and kills men when it
is internally taken by error." Kumagusu Minakata.

April 16.

I Here the author sayt; "It \% popularly called * ChanK-liu-Kan '
(= Witch-trrr-ront)." The name »hows that the root wa* used in witch-

Tafl,

j'.r !i.i l'nl;*rir.i..a,
the Chinese name

rhal of the Mandragora (r/ Hone, "The Year- Book,"
■|.

tion tuKKeiitcd for this name is that, as long as the fruit
mains unripe, the cuckoo continues 10 cry every night
•■u^r.). However, seeing thai the belief in the shrieks
' -vas once current among the Kuropeans (" Encyclo-
' Qth ed. vol. xv. p. 476), it would be more just to derive
Night Cry" from an analogous origin.

A Claim for Priority.

I SEND you, under ,'eparate cover, a copy of an address,
" Radiant Matter," &c. , delivered at the International Electrical
Exhibition, held in Philadelphia in 1SS4, reprinted from the
Journal oi \\\e Franklin Institute, September 1SS5. and would
call your attention to thede'Cription of the method of preparing
films of gold and other metals of extreme thinnes<, far exceed-
ing in tenuity those described in Nature as novelties in
metallurgical methods (prepared in identically the same manner),
and exhibited at a conversazione of the Riyal Society, June 13,
1894. The first published note regardin;» this subject may be
found in the Proceedings oi \.\\t .Vmeric:in Phil. Siic, vol. xcix.
February 16, 1S77. Later and fuller notices will be
found in fourn. Franklin /ntliluU, April 1877, June 1S77,
September 1SS5, and September 1894. In addition to the
above, the process was fully described in U.S. Patent, 19S, 209,
December 18, 1S77. Alex. E. Outerbkidge.

Philadelphia, April 5.

NO. 1330, VOL. 51]

I

AN IMPROVED METHOD FOR THE MICRO-
SCOPIC INVESTIGATIOX OF CRYSTALS.

A MEMOIR of consider.ible importance to all who
-'*• are interested in the microscopic determination of
the characters of crystals, is contributed by Prof. Klein
to the Sitzungsberichte of the Berlin Akadcinic der
IVtsse/isc/tafU/i (or ]3.nu:iTy ji, 1895 The two essential
points of the communication are that a form of stage
goniometer is described, which permits of the most com-
plete examination of many of the principal zones of the
crystal with one and the same setting of the crystal upon
its holder, and that the crystal is immersed during the
observations in a liquid whose refractive index is about
the mean of the refractive indices of the crystal. The
idea of the " Universaldrehapparat," as the new stage
goniometer is termed, appears to have suggested itself
almost simultaneously to Prof. Klein and to Herr von
Federow, for the former described an earlier form of it
in the Silcunx.iitri'c/ili: of April 1891, while the latter
published a description of an " Universaltischen" for
the mictoscope in the Zcitschrift fiir h'rystallns^rapftie
of May in the same year. Herr von Federow had pre-
viously contributed to the Zcitschrift a remarkable
memoir concerning a theodolitic universal goniometer,
and the application of the principle of that instrument
to the microscope goniometer followed naturally there-
from. The present memoir of Prof. Klein affords so
admirable a description of the improved instrument,
which has been constructed for him by the well-known
Berlin crystallographical optician, Herr Fuess, and like-
wise of the mode of employing it in connection with the
immersion method, that readers of N.VTUKi-; may find a
brief account of it not uninteresting. I'nfortunately this
description cannot well be illustrated, as I'rof. Klein's
illustrations are photographic reproductions which are
unsuitable for further reproduction.

The microscope should of course be one of the petro-
logical type, fitted with the usual accessories for the
examination of crystals in parallel and convergent
polarised light. The particular instrument constructed
for Prof. Klein is somewhat similar to the largest Fuess
model. It is so arranged with respect to the centre of
gravity that it can be rotated into the horizontal position
whenever desired, a point of some importance with
regard to the use of an immersion litpiid. The stage is
of course circular, and is divided so as to read with the
aid of a pair of verniers to single minutes ; it is further
provided above with two graduated rectangular traversing
movements, one of which is supplied with a micrometer
registering 001 m.m., while the other is capable of much
more rapid motion. The advantages of the simultaneous
rotation of the polarising and analysing nicols, as adopted
in the microscopes made by Mr. Swift under thedirection
of Mr. Allan Uick, have been so well appreciated by

April 25, 1895]

NA TURE

609

Prof. Klein, that this has been arranged for in the new
Fuess instrument. The carriers of the nicols are each
furnished with a toothed flange capable of gearing with
a smaller pinion, and the two pinions are arranged at
the ends of a connecting rod furnished at a convenient
height near the upper pinion with a milled flange by
means of which rotation can be effected. I'rovision is
made for the lengthening of the connecting rod when the
focussing of the microscope by the rack and pinion or by
the fine adjustment is effected, and care is also taken
that the rotation by means of the connecting rod shall
occur without dead-space or backlash. Prof Klein states
that some important details in connection with improve-
ments in the mode of carrying out this simultaneous
movement of polariser and analyser will shortly be pub-
lished by Herr Fuess. Provision has likewise been made
for correcting at any time the setting of the nicols in
their carriers, experience having shown that the setting
invariably alters slightly in course of time. In addition
to the eyepiece nicol capable of being connected with
the polariser in the manner just described, there is like-
wise provided the usual nicol capable of sliding in or out
of the microscope tube just over the objective. ."Xbove
this, and just below the eyepiece, a Bertrand lens for
observing interference figures in convergent light is
capable of sliding in and out of the tube, and is intended
to be employed in conjunction with a converging system
of lenses capable of being carried in a tube attachment
beneath the level of the stage. The remaining details
of the microscope are the same as are usually supplied
with the No. I Fuess instrument.

The stage goniometer is intended to be employed with
the microscope arranged horizontally, as it is found
mconvenient to employ an immersion liquid with a ver-
tical arrangement. The base-plate of the goniometer,
consisting of a stout metal plate with fairly large central
aperture, is fi.ved by a suitable clamping arrangement
upon the now vertical stage of the microscope. The
plate is continued into a short arm on that side which
is uppermost when fixed in position, and this arm carries
near its end, and at right angles to it (horizontal when
in position), a projecting piece terminating in the sup-
porting cone for the goniometer circle, and which also
carries the vernier reading to five minutes and the fine
adjustment. The circle is hollowed in its upper central
part, and perforated with a central aperture ; this permits
of the sliding movement within the hollow, for centering
purposes, of a disc which carries the axis of the instru-
ment. To the lower end of this short axis are attached
the movements for adjusting the crystal, and the lower
of which carries the crystal. The adjusting movements
are a pair of circular quadrants arranged at right angles
to each other and graduated. They are simpler in con-
struction, and lie much closer together than those of the
best forms of goniometer now in use for ordinary gonio-
metric and spectrometric work, and are thcreloie par-
ticularly suitable for use in connection with the micro-
scope. The upper quadrant is fixed to the axis ; over it
a slider is capable of moving, which carries a vernier,
and below it the lower quadrant, which in turn is fitted
with a slider terminating in the holder which carries
the crystal cemented by wax. The verniers enable read-
ings of five minutes to be obtained, the same degree of
accuracy as in the case of the circle.

The glass cell containing the immersion liquid is sup-
ported in position normal to the axis of the microscope
by means of a stand with an adjustable aim placed to the
left of the microscope. It is recommended to have a
series of cells, ready for filling with various media of the
most frequently required refractive power. The advan-
tages of Adams' method of determining optic axial
angles may also be combined with those of the method
now described, by use of a cell consisting of an upper
cylindrical portion terminating below in a sphere filled

NO. 1330, VOL. 51]

with the liquid. As regards suitable liquids, an admirable
list is given by Herr Pulfrich in his book descriptive of
the construction and use of the total-reflectometer
recently devised by him (p. 64). Two errors in that list,
however, are corrected by Prof. Klein ; he has been
unable to prepare the solution of mercuric iodide in ani-
line and quinoline of refractive index 22, and the refrac-
tive index of the phenyl sulphide kindly supplied by
Prof Klein's colleague, Prof Emil Fischer, is only r56
instead of r95. If the dangerously poisonous and in-
flammable liquids are excluded, the list consists chiefly
of oils, the well-known Thoulet solution, monobrom-
naphthalene, and methylene iodide. The solution of
iodine in the latter frequently renders it insufficiently
transparent for the purpose.

The determination of the true angle, 2\', between the
optic axes within the crystal, supposing it to be biaxial,
can at once be determined with the aid of the new ap-
paratus, by immersing the crystal in a liquid whose re-
fractive index is equal to the H (the intermediate)
refractive index of the crystal. The condensing system
of lenses is first inserted between the polarising nicol and
the stage, and the Bertrand lens above the analyser ; as
objective, either the ordinary wide angle combination
usually employed for convergent light work, or a specially
constructed one supplied for the particular purpose of
convergent light observations through an immersion
liquid, is employed. This objective is so constituted
that as large a field of vision as possible is afforded, while
the distance between objective and crystal is considerably
greater than with the ordinary systems in use. The ap-
parent angle of the optic axes in air, 2F, may first be
measured, if desired, after adjustment of the crystal by
means of the adjusting movements, by bringing the
hyperbolic brushes to the cross wire of the microscope
eyepiece in the usual manner. The immersion cell not
being in position while this is being achieved, the ob-
jective can be approached nearer to the crystal and one
of the ordinary forms of convergent light objective em-
ployed, which affords a larger ^.ngle of vision,
reserving the special objective for the determination
of the true angle of the optic axes. If, however,
the Adams spherical cell is employed, there is no
necessity even here to use the special objective, as
the older wide angle form serves admirably. With
the parallel sided cells it is preferable to use the
special objective. The Adams sphere is not supported
similarly to the rectangular cells, but is conveniently
held by its cylindrical neck in a small support directly
attached to the lower ciuadrant of the adjusting apparatus.
The measurement of the true angle of the optic axes is
then carried out in the usual manner, similarly to the de-
termination of the apparent angle in air, while the
crystal is immersed in the liquid contained in one or
other of the two forms of cell. Monochromatic light
should of course be used in making the observations,
a sodium flame some little distance in front of the
polariser being employed by Prof. Klein.

The great advantage of this method of determining
the true inner angle between the optic axes lies in the
fact that it is totally unnecessary to prepare section-
plates of the crystal, the whole crystal itself being em-
ployed, and thus material saved. Prof Klein does not
claim for it the highest attainable accuracy, and for the
class of work such as that with wliich the writer of this
article has become identified, the determination of the
crystallographic characters of series of isomorphous com-
pounds closely resembling each other, where every en-
deavour must be made to attain the upper limits of
experimental accuracy, such a method is of course
inadet|uate. But for the ordinary description of minerals
and the crystals of isolated chemical preparations
unlikely to be injured by the immersion liquid, and par-
ticularly for laboratory teaching, the method is one of

6io

NATURE

[April 25, 1895

the simplest and most interesting yet described. The
accuracy depends entirely upon the closeness of the ap-
proximation of the refractive index of the liquid to the
3 index of the crystal. Of course it will rarely happen
that coincidence of these values will occur for all colours
of the light employed, the dispersion of the crystal and
the liquid in general being diti'erent. So that although
the values may be coincident for sodium light, they would
in all probability be different for other colours. But if
the obsen-ations are only conducted for sodium light, a
process which is frequently sufficient for the purpose in
view, then this objection entirely disappears. Moreover,
the errors introduced by the discrepancy for different
wave-lengths of light would not be sufficiently large in
most cases, if observations for other colours were made,
to materially reduce the value of the method for the
purposes for which it was designed.

A consideration of the simple formulje connecting the
optic axial angle with the ,i refractive index and the
refractive index of an immersion liquid will at once
render the value of the method, within the above speci-
fied limits, clear. Representing as usual the real semi-
acute angle between the optic axes within the crystal by
A'a, the semi-obtuse angle by \'o, and the apparent semi-
acute and obtuse angles in the immersion liquid by Ha
and Ho respectively, the refractive index of the medium
for light of the same wave-length being n, then :

Sin Va

3

sin Ha and sin Vo

- sin Ho.

These two equations are of the same kind, for both
\'a and \'o are less than 90' ; and the only variables are
n sin Ha and n sin Ho, for i^, sin \'a, and sin \'o are
constant quantities for this wave-length of light. If, now,
the sum of the angles 2Ha and 2H0 is greater than iSo%
the common factor n must, in order to bring the sum of
these angles down equal to iSo', be increased, that is, a
liquid of higher refractive power be employed. Conversely
if the sum is less than iSo the refractive power of the
liquid must be diminished in order to bring the sum of
the an>;Ies up to iSo'. For the specially interesting
intermediate case where » = /3, the sum of 2 Ha and
2H0 will be exactly 180% and sin Va = sin Ha and sin
A'o = sin Ho, when also \a = Ha and V'o = Ho.

From the above theoretical considerations one can
immediately deduce the course to be taken to render the
immersion liquid exactly equal to the ,-i index of the
crystal ; if the measured values of 2Haand 2H0 add up
to over 180' a liquid of higher refraction must be
obtained, and vice versa if the sum is less than iSo .
There are, however, several ways of determining the
closeness of approximation of the indices without going
to the trouble of actually making preliminary measure-
ments. In the first place the crystal will disappear in
the liquid, that is to say, will be invisible, provided
that it is colourless, when its refractive power is
equal to that of the surrounding medium, especially
when the line of the observer's vision lies in the plane of
the optic axes. This is very beautifully observed when
calcite is immersed in monobromnaphthaline, and parti-
cularly when it is arranged so that the observer looks
along the direction of the vertical axis of the crystal ;
under these conditions the latter is completely invisible.
In the second place, instead of hyperbolic curves passing
through the positions occupied by the optic axes, the
brushes will take the form of almost straight lines when
the refraction of crystal and liquid is about the same.

In choosing crystals for observation by the new method,
I'rof Klein recommends that individuals or fragments
should be selected which arc equally thick in two perpen-
dicular directions in the plane of the optic axes, that is,
such as are almost cylindrical in appearance, and not
too thick to prevent the interference figures being ob-
served. When immersed in the liquid, it is as if at each

NO. 1330. VOL. 51]

moment, and for every position during rotation of the
cn'stal, a parallel section-plate were being examined, the
natural faces of the crystal — however rich in faces the
zone may be — not entering into consideration whatever.

The advantages of the use of an immersion liquid of
equal refractive power in the examination of crystals
have been pointed out by several previous observers, as
Prof Klein is careful to state. So long ago as \%i,\ Biot,
in his memoir concerning lamellar polarisation, describes
the use he made of it. The method has long remained
dormant, however, as far as is known from the literature
of this branch of study. In the oiijhth edition, however, of
the Lcltrbuch der Physik tind Mitcorologic of Joh.
Miiller, edited by L. Pfaundler in 1S79, it is stated that
if the refractive index of the liquid in which a plate per-
pendicular to one of the medium lines is immersed is
equal to that of the crystal, the true angle between the
optic axes is at once afforded. Latterly, however, the
evident advantages of the method have sug£;ested them-
selves to several crystallographers. ^L Fouquo men-
tions it in his memoir in the Bulletin of the French
Mineralogical Society of 1S94 on the felspars.

The writer of this article has frequently made use of
the method for certain specific purposes, and it may be
of use to other workers to give a brief indication of one
or two modes of extending its sphere of usefulness not
touched upon by Prof Klein. In the course of the in-
vestigation of the noriral sulphates of potassium, rubi-
dium, and caesium, the results of which were laid before
the Chemical Society last year (Journ. Chein. Soc. 1894,
62S, and Zeitscliri/t fiir Kryslallographie, 1894, xxiv. l),
a difficulty was fountl in determining the true optic axial
angle of rubidium sulphate by means of the very accu-
rately orientated section-plates prepared by use of the
new grinding goniometer described to the Royal Society
{Phil. Trans. 1S94, Series A, SS7) earlier in the same
year. The difficulty, which is one not uncommonly met
with, was owing to the fact that the extremely low double
refractir n, necessitating the use of very thick section-
plates, combined with the slight separation of the optic
axes, rendered it impossible to measure the obtuse angle
in monobromnaphthaline, and so to calculate the true

angle by means of the formula tan \'a = ,. ,, . The

Sin Ho

difficulty was surmounted, as fully described in the
memoir referred to, by measuring the .acute angle by
means of section-plates perpendicular to the first median
line immersed successively in two liquids, benzene and
cedar oil, whose refractive indices were nearly, and the
mean of them exactly, equal to the mean refractive index
of rubidium sulphate. The two series of values obtained
for six wave-lengths of light (the monochromatic light
producer recently described by the writer, Phil. Trans.
1S94, Series A, 913, being employed) were almost iden-
tical, differing only by a very few minutes, and the mean
for each wave-lenj^th was taken as representing the true
angle of separation of the optic axes for that particular
wave-length. The method is applicable to all cases
where it is found impossible to see the hyperbolic brushes
through a section perpendicular to the second median
line on account of the slight separation of the optic axes.
The suggestion to employ it was made to the writer by
Mr. Miers, of the British Museum, who has had a gonio-
meter constructed for the express purpose of studying
the use of an immersion liquid.

Another case in whichobservations in such a lic|uid are
of great value is when it is found desirable to confirm, in
some independent manner, the mode of dispersion of the
optic axes for different colours indicated by the calcu-
lated values of 2\'a. obtained from the formula last
quoted. Several of the compounds which the writer has
lately been engaged in studying exhibit very low dis-
persion of the optic axes, and the calculated values of

April 25, iHg^]

NATURE

611

zVa for five wave-lengths, obtained from the measure-
ments of the apparent acute and obtuse angles in mono-
bromnaphthalene by the use of accurately orientated
section-plates, are so close together that it was con-
sidered advisable to ascertain in some other manner
whether the order of dispersion was truly represented ;
that is, whether the angle for one end of the spectrum
was really very slightly greater than that for the other
end, or whether the amount of dispersion thus indicated
did not really fall within the limits of experimental
error, thus leaving it possible that the dispersion might
even be of the contrary order. By immersing a plate
perpendicular to the first median line in a liquid of re-
fractive power equal to the medium refractive index of
the crystal, the interference figure in white light usually
at once indicates, by the colours exhibited on the margins
of the axial brushes, the order of dispersion, and measure-
ments of the axial angle for the two extreme wave-
lengths afford an immediate check upon the accuracy of
the calculated angles. It is a considerable source of
satisfaction to be able to confirm such calculated optic
axial angles in so simple a manner.

Prof Klein further describes how admirably the new
apparatus is adapted for the determination of the ex-
tinction angles upon the various faces of a zone, in
parallel polarised light. For this purpose the converging
lenses are removed, and the eyepiece analysing nicol is
employed, so that the polarising and analysing nicols
may be arranged for simultaneous rotation. The mea-
surements are earned out while the crystal is immersed in
the liquid as in case of the determinations of optic axial
angle. The only precaution necessary is that the crystal
should be uniformly illuminated in order that the exact
position of extinction may be ascertained by use of one
of the usual half-shadow stauroscopic plates.

The memoir concludes with a description of the general
mode of investigating a biaxial crystal immersed in a
liquid of equal refractive power, indicating how the
principal planes of optical elasticity may be found, the
positions of the optic axes ascertained, and the true
internal angle of the latter measured. One of the most
important advantages of the method is the simplification
which it introduces into the study of triclinic crystals,
hitherto almost dreaded by the crystallographer for the
trouble they involve. It would appear that their optical
investigation by the immersion method otters but slightly
more aitticulty than that of crystals of higher symmetry,
the positions of the optic axes being readily found, and
the true angle at once i.iTorded. This alone would
entitle Prof. Klein to the thanks of crystallographers and
mineralogists for perfecting so admirable an aid to
investigation. A. E. TUTTON.

MICROBES AND METALS.

'T'HE effect of metals on the growth of bacteria has
■*■ been examined by Miller, Behring, and others, and
another contribution to this subject has lately been pub-
lished by Ur. Meade Bolton, in the December number of
the International Medical Magazine. According to
Uffelmann, who smeared the surface of copper coins
with liquefied jelly-cultures of cholera bacilli, the latter
were destroyed in seventeen minutes ; whilst on a brass
coin they were alive after thirty hours, but dead after
sixty hours. Bolton employed Miller's method of in-
oculating a tube of melted jelly with particular microbes,
and pouring the contents out on a sterilised glass-plate,
after which bits of the metal under examination were laid
on the jelly whilst it was still soft. If the metal has an
inhibitory action on the microbes, then a clear zone is
left around the metal after the colonies have developed
in the other parts of the jelly. The width of this zone.
Dr. Bolton found, varied very considerably with different

NO. 1330, VOL. 51]

organisms, as well as with different metals. Thus care-
fully purified bits of silver produced in the case of cholera
bacilli a clear zone 5 millimetres broad, in the case of
typhoid bacilli a zone of about i millimetre, whilst with
the closely allied colon bacillus a zone of about 5 milli-
metres was produced. In the case of purified gold,
no inhibition was observed with the staphylococcus
pyogenes aureus, colon bacillus, typhoid bacillus, or
cholera bacillus. Freshly " glowed gold" had invariably
no inhibitory action ; and in the few cases where inhibition
was observed, the gold had not been glowed for several
weeks. Pure nickel, platinum wire, and platinum black
aluminium, silicon, and niobium, again, also failed to
give any reaction with most of the microbes examined.
Throughout the investigations it was found that those
metals that are resistant towards chemical reagents in
general, failed to produce any effect on microbes ;
whilst, on the other hand, those metals which are readily
attacked by chemical reagents, all exhibited a marked
inhibitory action upon the growth of bacteria. This
result is probably due to a solution of the metal taking
place in the medium. The length of time it is necessary
to leave the metals in contact with the jelly, to produce
an effect on the microbes present, was tried ^vitli brass,
copper, cadmium, and zinc, on the staphylococcus
pyogenes aureus. The metals were put on and removed
at various intervals. When cadmium was left on for a
minute, there was a clear space underneath where it had
rested, which extended to I millimetre round ; when it was
left on for three or four minutes, the clear space usually
extended over 3 millimetres. Very similar results were
obtained with zinc. With brass no effect was produced
when it was left on thirty-six minutes, but after this there
was more and more marked inhibition up to fifty
minutes ; but to produce a clear space, it was necessary
to leave it on for still longer. Copper produced no
visible effect under thirty-six minutes, and fifty minutes
was required to produce a clear space.

G. C. Frank L.A.XD.

PROFESSOR JAMES DWIGHT DANA.

BY the sudden death of Prof. J. D. Dana, from heart-
failure, on April 15, .America has lost a veteran man
of science, who in his time has not only played many
widely varied parts, but has reached the highest excel-
lence in each. .Vs a mineralogist he published, solong ago
as 1S37, the first edition of a " Descriptive Mineralogy,"
which by reason of its completeness and accuracy soon
became a standard work of reference throughout the
civilised world, and of which the sixth edition (113+
pages), issued in 1S92 under the superintendence of his
distinguished son. Prof. Edward Salisbury Dana, still
maintains the high reputation attained by the original
work. As a geologist and paleontologist, he published
in iS63a similarly excellent and well-illustrated " .Manual
of Geology," having special regard to the geology of the
North American continent, and of which the fourth
edition (10S7 pages) was issued only two or three months
ago. Of his work as a zoologist, we may cite as example
his elaborate report on the zoophytes, collected by an
expedition in which he took a very active part. The
report is illustrated by 61 plates, and in it are described
no fewer than 230 new species. Attainments so diverse
belong only to the few.

James Dwight Dana was born on February 12, 1813,
at I'tica, in the State of New York, U.S.A.. and was
therefore in his eighty-third year at the time of his death.
He was educated at Yale College, New Haven, Con-
necticut, receiving there a sound training in mathematics,
physics and chemistry, which was of the greatest service
to him in his subsequent career ; he proceeded to his

6l2

NA TURE

[April 25, 1895

degree in the year 1S33. His appointment as Instructor
of Mathematics to the midshipmen of the United States
Navy gave him splendid opportunities for the study of
nature in various parts of the world, particularly in
France, Italy, and Turkey, opportunities of which he was
not slow to avail himself; more especially was his at-
tention attracted to the study of volcanic phenomena by
an ascent of X'esuvius, a sight of Stromboli, and an
excursion in the Island of Milo in the year 1S34. Settling
down for a short time, he acted as chemical assistant at
Yale College to his old teacher and friend, Prof. Silliman
(1836-38) ; but an opportunity again presenting jitself
of making a long voyage of marine observation, he
accepted the appointment of mineralogist and geologist
to the United States exploring expedition, which was to
proceed round the world. This expedition, under Charles
Wilkes as Commander, was admirably equipped for the
objects in view, and consisted of two sloops-of-war,
a store-ship, and a brig ; the cruise extended over four
years (1838-42), and the scientific staff included, in ad-
dition to Dana, Pickering, Couthoy, and Peale as
zoologists, Rich and Breckenridge as botanists, and Hale
as philologist. The memory of the events, scenes and
labours of this cruise was a constant joy to him during
the remaining fifty-three years of life. On at least two
occasions, however, he was in imminent peril : at one
time his vessel narrowly escaped destruction on the
rocks of Southern Fuegia, when the sea was dashing up
the cliffs to a height of two or three hundred feet, and all
the anchors had given way ; at another time his party
had to take to the boats empty-handed, and some hours
afterwards they saw the last vestige of the vessel which
had been their home for three years disappear beneath
the waves.

The study of the material collected by the expedition
and the preparation of his reports occupied all the
available time during the next thirteen years. The first
two or three years were spent at Washington, but after
his marriage to the daughter of Prof Silliman he
removed back to New Haven, where he passed the rest
of his life. In 1S50 he was appointed Silliman
Professor of Geology and Natural History at Yale
College. In 1846 Mr. Dana had become associate-editor
of the American Journal of Science, and after the death
of Prof. Silliman, in 1S64, he became the principal editor
of that important scientific organ.

Dana gave special attention to corals and coral
islands, and also to volcanoes. The Wilkes expedition
of 1838-42 followed in part the course taken by the
Beagle in 1831-36, and even where it diverged from that
route visited coral and volcanic islands such as have
been carefully described by Charles Darwin. When the
Wilkes expedition reached Sydney in 1839, Dana read
in the papers a brief statement of Darwm's theory of
the origin of the atoll and barrier forms of reefs ; this
mere paragraph was a great help to him in his
later work, and he afterwards regarded Darwin with
feelmgs of the deepest gratitude. A visit to the Fiji
Islands in 1840 brought before him facts such as had
been already noticed by Darwin elsewhere ; but there
they were on a still grander scale and of a more diversified
character, thus enabling him to speak even more posi-
tively of the theory than Darwin himself had thought it
philosophic to do. On other points the conclusions
arrived at by Darwin and Dana, independently of each
other, were for the most part the same, and differed only
in comparatively unimportant details. Dana's special
labours relative to corals ceased with the publication of
his report on the zoophytes collected by the expedition,
but an elaborate account (406 pages) of 'Corals and
Coral Islands was prepared by him and issued in 1879:
this was an extension of his expedition-report on Coral
Keefs and Coral Islands, which had been separately
published in 1853. In 1893 appeared another consider-

NO. 1330, VOL. 5 1]

able work (399 pages) entitled "Characteristics of
\'olcanoes, with contributions of facts and principles
from the Hawaiian Islands," which placed on record
much useful information collected by him during his
travels.

In addition to these larger works, he was the author
of about two hundred separate papers. Some of them
are of a physical character : his first paper, published as
far back as 1833, dealing with the connection of electri-
city, heat and magnetism ; subsequent papers treated of
galvano-magnetic apparatus and the laws of cohesive
attraction as exemplified by crystals. t)ther papers, of a
purely crystallographic character (1S35-52), treated of the
drawing and lettering of crystal figures, of crystallo-
graphic symbols, and of the formation of twin growths ;
a series of volcanic papers discussed both lunar and
terrestrial volcanoes, the latter including those of Vesu-
vius, Cotopaxi, Arequipa, Mauna Loa, and Kilauea
(1835-68) ; a set of coral papers treated of the tempera-
ture limiting the distribution of coral?, on the area of
subsidence in the Pacific as indicated by the distribution
of coral islands, on the composition of corals and on
fossil corals (1S43-74).

About forty papers are on mineralogical topics : many
of them are descriptive of particular mineral species ;
others treat of general subjects, such as nomenclature,
pseudomorphism, honiceomorphism, the connection
between crystalline form and chemical constitution,
and the origin of the constituent and adventitious
minerals of trap and the allied rocks. As illustrations
of the variety met with in his geological publications, we
may cite his papers on the origin of the grand outline
features of the earth, the origin of continents,
mountains and prairies, the early condition of the
earth's surface, the analogies between the modern
igneous rocks and the so-called primary formations, on
erosion, on denudation in the Pacific, on terraces, on
southern New England during the melting of the great
glacier, on the degradation of the rocks of New South
Wales, and the formation of valleys. The remaining
papers, about seventy in number, deal with biological sub-
jects, both recent and fossil, and have a similarly varied
character ; some being descriptive of species, others
treating of classification and similarly general problems.

The importance of this scientific work was widely
recognised, and many marks of distinction were conferred
upon him, both at home and abroad. He was an
original member of the National Academy of Sciences
of the United States, and in the year 1854 occupied the
presidential chair of the American Association for the
.Vdvancement of .Science. In 1851 he was elected a
Foreign Member of the Geological Society of London,
and in 1872 received from that Society the Wollaston
-Medal, the highest compliment the tieological Society
can pay to the man of science ; in the same year the
University of .Munich honoured him with the degree of
Ph.D. ; in 1877 he was the recipient of the Copley
Medal of the Royal Society, and in 1SS4 was elected one
of the foreign members ; in 1S86 Harvard conferred
upon him the degree of LL.D. ; he was also an honorary
member of the -Academies of Paris, lierlin, Vienna, St.
Petersburg and Rome, and of the Slineralogical
Societies of England and of France.

NOTES.
With the l^^cole Normale at Paris, wlilcli has just celebrated
its cenlcnary, the names of a number of distinguished men of
science are associated. At the present time, no less than
twelve of its old students are members of the Academy of
Sciences. Pasteur left Lille to become the direclor of scientific
studies at the school, and carried on, while in connection with il,
the researches which have made his name known thruughout

April 25. 1895]

NATURE

613

the world. M. Bertrand, the Perpetual Secretary of the
Academy, is an old student of the school, and among other
eminent names included in the list of its alumni are MM. Dar-
boux, Joubert, Serret, Hermite, Puiseux, Briol, Bouquet,
Giard, Baillaud, Chaive, Floquet, Pellet, Tisserand, Appell,
Picard, &c. ; while the teaching staff now contains such men as
Goursat, Tannery, Gernez, Dufet, Iloussay, Constantin, Raffy,
Violle, Joly, and Wallerant.

An influential committee has been formed for the erection of
a monument to the late Prof. Hermann von Helmholtz, the
German Emperor having promised lo.ooo marks and a free site
for the purpose. The committee is international and thoroughly
representative, as shown by (he names of Berthelot, Blaserna,
Boltzmann, Geikie, Holmgren, Kekule, Kelvin, Lippmann,
Lubbock, Pictet, Rayleigh, Roscoe, Sidgwick, Siemens, Tail,
Thalen, Virchow, Weber, and others among the i8o dis-
tinguished men of science forming the committee. Funds will
be collected in Germany and in other countries, and may be
sent to any member of the committee, or to Messrs. Mendelssohn
and Co., Berlin W., Jaegerstrasse 49 and 50. Letters may
be sent to Prof. Dr. A. Konig, Berlin N.W. , Flemmingstrasse I.
The appeal issued by the committee concludes as follows :
"Friends and admirers of Hermann von Helmholt? far and
near, unite with us ! Bear witness to the homage paid by science,
which knows no frontiers, to one of its heroes ; show your
gratitude for the benefits which life has received from his
scientific labours, and give expression to the love which his
harmonious spirit won wherever he appeared."

Prof. Huxley's condition during the past week has caused
his friends considerable anxiety, but we are glad to learn that a
change for the better set in on Monday.

Dr. John H. Redfield, one of the founders of the American
Association for the .A.dvancement of Science, died recently at
Philadelphia.

The Prince of Wales his signified his intention to be present
at the celebration of the jubilee of the Royal Agricultural
College, Cirencester, on July 25.

The sixty-seventh meeting of the Society of German
Naturalists and Physicians will be held this year at Liibeck,
September 16 to 21. The secretaries of the zoological section
are already making preparations for this event, and will issue a
preliminary programme of communications^and demonstrations
early in July.

The London Geological Field Class will commence their
sSries of Saturday afternoon excursions, under the direclion of
Prof. H. G. Seeley, F. U.S., ne.'it Saturday, when they will
visit Otford and,Eynsford. F>urther particulars can be obtained
from the General Secretary, R. Herbert Hentley, 31, Adolphus
Road, Brownswood Park, N.

Mr. Edward Crossley has signified his intention of
presenting to the Lick Observatory the 3-foot reflecting
telescope, with its dome, which now form part of his private
observatory at Halifax. This information comes to us directly
from the Lick Observatory, together with an expression of high
appreciation of Mr. Crossley 's most generous gift.

Application.s for appointment to the Medical Research
Scholarships of the Grocers' Company must be sent in before
the end of this month. The Scholarships are three in number,
each of the value of ;£^250, and are open only to British sub-
jects; they were instituted by the Company as an encourage-
ment to exact research into the nature and prevention of
important diseases.

NO. 1330, VOL. 51]

At Stevens's sale room on Tuesday, a fine and well-preserved
specimen of the Great Auk, from the collection of the late Sir
William Milner, was put up to auction. About eighty skins
of the bird are known to be in existence, of which twenty-foar
are in Great Britain, ten of these being in museums, and
fourteen in private hands. The bidding for the specimen
offered for sale by Mr. Stevens started at 100 guineas, and
went up slowly to 350 guineas ; but as this was lower than the
reserve price, the bird did not change owners. A Great Auk's
egg, offered at the same sale, reached the price of i8o guineas,
while an egg of ^pyornis maximus was sold for 36 guineas.

A PARTY, consisting of Dr. Geo. Becker, Prof. W. H. Dall.and
Mr. Parington, of the U.S. Geological Survey, will leave Wash-
ington on May 16 for Alaska, and will be away until September.
Congress recently directed an examination of the gold and coal
deposits of the territory to be made, and this will be the work
of the party ; directed more especially towards an estimate of '
the economic value of the known deposits, rather than toward
a search for new ones.

The new system — the " Systeme fran9ais" — proposed by
the French Socitfte d'Encouragement to regulate the pitch of
screws, and the metric wire gauge — the " Jauge decimate
metrique " — in which the number of a wire is the same as the
diameter expressed in tenths of millimetres, have been adopted
in the French Navy by the Minister of Marine. The approva
thus officially shown to the new scales will greatly assist the
Society in its efforts to establish uniform gauges for wires and
screw-threads.

The news that the office of Superintendent of Agriculture,
held by Mr. C. A. Barber in the Leeward Islands, has been
abolished, and that the Department of Agriculture, as such, no
longer exist?, is altogether surprising. The Department was
only opened towards the end of 1S91, but, under Mr. Barber's
direction, the four botanical stations in connection with it, at
Antigua, Dominica, St. Kitts, and Montserrat, have done a large
amount of work, which is daily becoming more and more ■ known
?nd appreciated. No agricultural community can afford to be
without scientific advice in these days of competition and plant
disease. Why the local Legislature should dispense with this ad-
vice just when the Superintendent of their Department of Agri-
culture had, by incessant stndy of the climatal and economic
conditions of the islands, attained the position to give it
authoritatively, is quite beyond our comprehension.

The "Exposition annuelle" of the French Physical
Society was held last week. Many new and ingenious pieces
of apparatus, for use in all branches of physical investigation
and instruction, were on view. Electrical instruments
occupied a large share of ihe exhibits, but there were also to
be seen new forms of barometers, thermometers, calorimeters,
spectroscopes, dynamometers, balances, ani other engines of
research. M. Violle exhibited photographs of the electric
arc, and MM. Loewy and Puiseux showed their lunar photo-
graphs obtained at the Paris Observatory. Useful accessories
to micrometers for astronomical telescopes were shown by M.
Maurice Hamy. There were also on view, among numerous
other things, metals of new compounds prepared by M.
Moissan in his electric furn.ice ; a radiometer which turned
in the opposite direclion to that of the ordinary form of the
instrument ; M. Janssen's long-period meteorograph, designed
for the Mont Bl.anc Observatory ; M. Raoul Pictet's
apparatus for the experimental study of the critical points of
liquids ; and the spectrum of argon. Visitors to the Exhibition
must have derived considerable benefit from an inspection of
the many physical instruments and devices which were to be
seen.

6i4

NA TURK

[April 25, 1895

Major Cardew's report on the inquiry which he has made
into the circumstances connected with a series of explosions
which occurred on February I, on Southwaik Bridge, has just
been printed x-; a Parliamentary Paper. It will be remembered
that there were four explosions ; the first, and by far the most
intense, occurred in the culvert under the pavement and road-
way on the west side of the bridge, and it was immediately fol-
lowed by three explosions in the street boxes of the Electric
Lighting Company, on the east side of the bridge. On
opening the ground over the culvert, shortly after the explosions,
a large crack was found in the 3-inch gas main, out of which
the gas was coming in volumes. How the gas was fired could
not be exactly ascertained, but Major Cardew confidently
asserts that it was not by means of the electric lighting mains.
The most striking features about the accident seem
to be: (l) The distance to which it appears that a
series of explosions may travel along the electric mains
which form a gigantic network under the whole of the
streets of the city ; and (2) the proof it affords of the in-
sufficiency of any ordinary system of ventilation of these pipes
and street boxes, if gas can find an easy access to them, and
the necessity of exercising great care to make and keep the
street boxes impervious to gas. In a former report it was
recommended that " accumulation of gas should be prevented by
thorough ventilation, by makmg the sides and bottoms of street
boxes impervious to gas, and by fillmg up the boxes as far
as practicable with incombustible material " ; to this Major
Cardew now adds — " by thoroughly plugging pipes and conduits
at each street box to prevent passage of gas along the system,"
and he puts the filling up the boxes first, as the most simple
and certain method of preventing danger of explosion. It is
admitted that the main c.iuse of the explosions was the defect in
the gas-pipe, and this again directs attention to the very serious
danger to the public arising from the condition of the gas-pipes
in many districts, and the way in which they are laid and
supported ; a danger which is continually increasing, owing to
the spread of the use of wood paving and other impervious
sui faces, and which is temporarily intensified' by every severe
frost. No want of care on the part of the gas companies can,
however, relieve electric lighting companies of the duty of
sufficiently protecting their conduits and street boxes against an
accumulation of gas, by acting on the recommendations made.

It is very commonly believed that in Ireland, on account of
the mild climate, the Arctic or Mountain Hare does not turn
while in winter, but remains in its brown summer fur. Writing
in the Zoologist, Dr. R. F. ScharfT brings evidence that there is
no change in the colour of the Irish hare in most winters. But,
on the other hand, Major-General Warrand states that — "At
Fionebrogue, near Downpatrick, a very large number of hares
are taken or killed every year, and it is found that a consider-
able number of them turn very white in the winter, while nearly
all assume a much lighter shade of fur when the cold weather
sets in." The editor of the Zoologist says that this view is sup-
ported by a number of sportsmen and good observers, and that
he himself has shot several Irish hares in all stages of change
from brown to white.

There is an interesting paper in the Eleclrician, by
Messri. Campbell and Lovell, on the supposed magnetic
fatigue. Prof. Ewing has recently shown that in the case of
good wrought iron, when subjected to very many reversals in
weak magnetising fields, there is no perceptible change in the
magnetic qualities. The authors have made use of strong
magneti>ing fields, and have experimented on cast as well as
wrought iron. The specimens to be tested were in the form of
ringi wound over with primary and secondary coils. A single
B.H. curve wxs taken by the oidinary ballistic method, and

NO. 1330. VOL. 51]

then an alternating current of about X'i, amperes at S3 alter-
nations per second was kept passing through the primary coil
for nearly a month. Another series of tests were then made,
and it was found that the B.H. curve obtained coincided exactly
with that given before the repeated reversals, both in the case of
wrought and cast iron.

The current number of Wiedemann's AnnaUn contaiiis a
paper, by Ilerr A. Bock, on the ratio between the Literal con.
traction and the longitudinal dilatation (Poisson's ratio) in
magnetised iron rods. In the method employed the rod under
test is rigidly supported at its middle, so that it lies in
a horizontal plane. At either end of the rod a cross-piece is
attached, as well as a plane mirror. These cross-pieces serve
as lever arms, from the ends of which weights can be hung. In
this way the bar is both bent and twisted, the amount of bend-
ing and twisting being read oft by means of a vertical tele-
scope, two scales at right angles, and the mirrors attached to
the ends of the rod. The difference of the readings on the
scale parallel to the length of the rod (B) is proportional to the
bending, while the difference in the readings on the scale at
right angles to the length of the rod (T) is proportional to the
twist. Then using Kirchhoff's formula, Poisson's ratio is given

by /I = . - - I, where -s is the half length of the rod, and

/ is the length of the lever arm, at the end of which the deform-
ing weight acts. Neither in the case of hard steel or soft iron
(a magnetising coil being used in this latter case) was a differ-
ence in Young's modulus, or of the torsional rigidity greater
than 05 per cent, observed. In the c-ise of soft iron, the author
considers that his experiments are sufficiently accurate to show
that after magnetisation the torsional rigidity and Young's
modulus both diminish. Since, however, B diminishes laster
than T, the value of Poisson's ratio increases. The author
finds that frequent magnetisation and deformation causes the
differences in the elastic constants between the magnetised and
unmagnetised states to diminish, and he therefore concludes
that it is not possible to detect the effect on the elasticity of
magnetisation in a rod by the change in the pitch of the note it
emits when struck.

The field experiments now in progress in various parts of the
country partake rather of the character of demonstrations than
of incursions into. the domain of original research. The ex-
periments made in Carnarvonshire last year, in connection with
the agricultural department of University College, Bangor, in-
cluded a serici in which a mixture of rye grass and clover seeds
was pitted against mixtures containing the seeds of other grasses
than rye grass, in addition to or exclusive of the latter. The
crops were cut in July, and weighed green, when the crop con-
taining clovers and rye grass only was found to be the heaviest.
All the plots are to be grazed for the next three years, and it is
obvious that considerable time must be allowed before definite
conclusions can be arrived at. Experiments made in Anglesey
" to test the best quantity of seed to sow for oats," appear pro-
visionally to demonstrate that four or six bushels of seed (black
Tartarian) broad-castcd per acre, give better crops than are
obtained from eight bushels of seed, the quantity sown under
the usual practice of the island. In both counties comparative
manurial experiments are in progress upon pasture land and
field crops.

The work of the Aberdeenshire Agricultural Research
Association in 181J4 was largely concerned with an inquiry into
"degeneration of rye grass and passible recovery." It isargued
that, in permanent pasture, "starvation of plants, and non-
utilisation of the plants when grown, are the features to be
remedied, in order to secure permanent pas'.ure of the valued
ryegrass." The supreme value of I.olium pcrenne in pastures.

I

April 25, 1895]

NATURE

61

as demonstrated by Sir John Lawes and others a few years ago,
appears to be steadily acquiring additional confirmation in
different parts of the country, and the economic importance of
the question is beyond all doubt. We are afraid that confusion
is likely to arise from the adoption of a practice in vogue at
some of the American experiment stations, where the word
"legume" is used to denote "leguminous (papilionaceous)
plant." In this report we read, "Legumes (i.i. tares, peas,
clover, lucerne, &c.)." The word "legume" has already a
definite meaning attached to it by English botanists, whilst in
colloquial use in France it has another and a wider application.
Exception should also be taken to the use of the term tuber-
cules {or tubercles) to denote the structures on the roots of
leguminous plants. Lawes and Gilbert have, with admirable
consistency, adhered throughout to the word " nodules," and it
is unfortunate that this example has not generally been followed.
Students of agriculture are hearing more and more of tubercle in
animals, and of the disease termed tuberculosis, and there is a
tendency, at least on the part of beginners, to think that all
tubercles must be alike. The general adoption of the word
"nodules," as used by Lawes and Gilbert, would lessen the
possibility of confusion.

Miss Christine Ladd Franklin publishes au interesting
paper on "The Normal Defect of Vision in the I'ovea" in
the current number of the Psychological Kevie-M. Recent in-
vestigations of Kbnigs on the relative absorption of different
portions of the spectrum by the visual purple, the curve of which
corresponds with the curve which expresses the distribution of
brightness along the spectrum for (i) the totally colour-blind
and (2) the normal eye in a faint light, suggest that vision both
in (l) and (2) is conditioned by the presence of visual purple in
the retina. But this visual purple is absent in the fovea. If
this be so, the eye in (i) and (2) should be blind in that part
of the retina. Careful observations and experiments were made
to test the validity of this conclusion. " The blindness of the
fovea for faint light did not at once reveal itself ; the act of
fixation means holding the eye so that an image falls on the part
of the retina best adapted for seeing it, and hence it would in-
volve keeping the image out of the fovea in a faint light, if the
fovea were then really blind. But after the total disappearance
of the small bright object looked at had several limes occurred
by accident, it became possible to execute the motion of the eye
necessary to secure it at pleasure. It was then found that the
simple device of presenting a group of small bright objects to
the eye of the observer was sufficient to demonstrate the
'normal night-blindness of the fovea' without any difficulty —
one or other of them is sure to fall into the dark hole of the
fovea by accident." Observations on a totally colour-blind
boy showed the blindness of his fovea. The function of the
retinal purple is, it is suggested, for the reinforcement of waning
light, and is especially adapted for the absorption of the faint
green light of dense forests.

The Calendar of Queen's College, Galway, for 1894-95, has
just been published, and also that of the Royal University of
Ireland, for the year 1895.

The current number of the Journaloi the Royal Agricultural
Society of England contains a long report, by Sir J. li. Lawes,
F.R.S., and Sir J. H. Gilbert, F.R.S., on "The Feeding of
Animals for the Production of Meat, Milk, and Manure, and
for the Exercise of Force."

A NEW edition has been published of " Stephens' Catechism
of Practical Agriculture " (\V. Blackwood and Sons), revised and
largely rewritten by Mr. James Macdonald. . The popularity of
the book is vouched for by the fact that more than twenty-one
thousand copies have been sold.

NO. 1330, VOL. 51]

TwENTV-EiGHT short cssays by Dr. Jean Rey, " On an in-
quiry into the cause wherefore tin and lead increase in weight
on calcination," form the contents of No. 1 1 of the .\lembic
Club Reprints. The essays, which originally appeared in 1630,
are interesting because they contain descriptions of experiments
and results which anticipated, to some extent, the work done by
Lavoisier a century and a half later.

P.\RT3 of the first and second editions of Malthus' essay on the
principle of population, have been published, in a handy volume,
in Messrs. Macmillan's series of Economic Classics, edited by
Mr. J. Ashley. Of the first edition, published in 1798, about
one-third has been reprinted ; but of the second edition, which
contained ab:)ut four times as much matter, the selected
chapters are only one-twentieth of the whole work.

An account of principles and practice of the methods adopted
by Dr. T. Schott in the treatment of chronic diseases of the
heart by means of mineral baths and exercises, has been written
by Dr. Bezly Thorne, and published by Messrs. J. and A.
Churchill, together with a description of the Nauheim baths,
and of the therapeutic exercises. The volume is full of diagrams
and other illustrations of interest to students of cardiac
affections.

A German edition of Mr. Benjamin Kidd's " Social Evolu-
tion," with a preface by Dr. \. Weismann, has just been
published by Gustav Fischer, Jena.

Five new volumes belonging to the " Encyclopciie scienti-
fique des Aide-Mcmoire " have come to us from the joint
publishers, GauthierVillars and G. Misson, Paris. They are :
" Le Fonctionnement des Machines a Vapeur," by G. Leloutre ;
"Des Maii-es," by P. Hatt ; " Balistique des Nouvelles Pou-
dres," by E. Vallier ; "La Thcorie des Procedes Photo-
graphiques," by A. de la Bau'me Pluvinel ; and " La Distilla-
tion," by E. Sorel.

Indexes to the literature of cerium and lanthanum, by Dr.
W. G. Magee, have been published together as No. 971 of the
" Smithsonian Miscellaneous Collections," in accordance with
the recommendation of the Chemical Literature Committee of
the American Association for the Advancement of Science.
The difficulty and labour involved in the preparation of these
indexes can only be fully understood by thosi who have
attempted similar tasks. All chemists should be grateful to
Dr. Magee for his very valuable bibliography.

A FULL notice of the life and numerous works of the late Mr.
F. Buchanan White appears, with a portrait, in the April num-
ber of the Annals of Scottish Natural History. A report on the
remarkable visitation of the Little .Vuk to Scotland, during the
past winter, is contributed to the same number by Mr. W. E.
Clarke. The whole of the records of occurrences of the bird
from December 22, 1894, to February, are shown upon a map
which accompanies the report, and arc also precisely tabulated
in chronological sequence.

Dr. Henry Maudsley's "Pathology of Mind" (Mac-
millan) has recently been published in such an altered and
enlarged form, that it is virtually a new book, " for," to quote
from the preface, "while old matter has been left out, and much
fresh matter added, the whole jhaj been recast, the form of the
presentation changed, and the text entirely rewritten." The
present contents of the work, as expressed by the new sub-
title, constitute a study of the distempers, deformities, and
disorders of the mind.

In the third Bulletin of the Madras Government Museum
appears a revised edition of Mr. Edgar Thurston's " K.imes-
varam Island and the Fauna of the Gulf of Manaar." The

6i6

NA TURE

[April 25, 1895

sitnation of Rimcsvaram, on the reef which, under the name of
Adam's Bridge, almost connects Ceylon wi;h the mainland of
India, renders an account of its flora and fauna particularly
interesting ; and the present brochure, which is illustrated with
several charts and photographs of the coast, furnishes a useful
supplement to Haeckel's graphic pages upon the island of
Ceylon. The observations recorded are admitted to be far from
exhaustive of the biological features of the Gulf of Manaar, but
they are more than sufficient tJ indicate the existence of a fauna
well worthy of further examination.

The Malacological Society of London, instituted for the
study of the Molluscaand Brachiopoda, only came into existence
in February 1S93, but its performances up to now give every
promise of a successful future. It publishes Proceedings, in
which appear anatomical papers, and papers devoted to de-
scriptions of recent and fossil shells. A valuable address by
Dr. H. Woodward, F.R.S., dealing largely with scientific in-
vestigations of the sea and its inhabitants, appears in the fourth
number of the Society's Proceedings, with a number of other
papers. In this connection we notice that the Journal of Mala-
eology conl3.\Tts a contribution, by Dr. J. C. Thresh, on "Oysters
as Disseminators of Disease," and, together with several other
communications and a bibliography of recent literature, an in-
teresting note, by Mr. W. M. Webb, on " The Dimyarian Stage
of the Native Oyster."

The Natural History Societies in our public schools probably
do more to foster scientific research than all the systematic
instruction in lecture-room and laboratory ; therefore every
encouragement should be given to the work of observation
and collection which is carried on by them. Increased de-
mands of both school work and games on half-holidays leave
little time to cultivate interest, in natural things, and this
accounts partly for the statement in the report of the Rugby
School Natural History Society for 1894, that the interest
shown in the .Society by members of the school has decreased.
Possibly, now that the new museum is completed, and the col-
lections in it are being systematically arranged by Mr. Collinge,
the Society will commence a new era of prosperity.

The Danish Meteorological Institute and the Deutsche See-
warte have conjointly published daily synoptic weather charts
of the North Atlantic Ocean and adjacent continents for a year
ending November 1889. These valuable charts were first
issued for September 1873 by the late Captain Iloffmeyer, of
Copenhagen, and they afford excellent materials for tracing the
connection between the weather conditions of the Atlantic,
this country, and Western Europe. For some years past the
charts have been accompanied by explanatory text, which
greatly enhances theii value. The discussion of the charts for
the year in question is divided into two parts: (1) general
investigations of the conditions over the North Atlantic, and
(2) application of this knowledge to navigation ; while the
position and movement of the areas of high and low barometer,
in interesting cases, are shown in forty special charts accom-
panying the text.

Several aromatic esters of arsenious .acid have been pre-
pared for the first time by Ur. Fromm, of Rostock. The new
substances are either viscous liquids or crystalline solids, and
arc prepared with considerable facility. The first member of
the series, the triphenyl ester, As(OC|,Hj)„ is obtained by
allowing arsenic trichloride diluted with ether to fall drop by
drop into sodium phenylate suspended in ether. The reaction
commences vigorously at the ordinary temperature, but the
mixture eventually requires warmin^j over a water bath in order
to obtain the theoretical yield. The ethereal liquid is then
allowed to stand until the finely-divided precipitate of common

NO. 1330, VOL. 51]

salt subsides, when it is decanted frou the latter. The ether is
then removed by distillation over the wa'er bith, and the thick
residual liquid subsequently subjected to distillation under re-
duced pressure. Arsenious triphenyl ester is a colourless
viscous liquid endowed with an odour somewhat resembling
that of phenol ; it boils under a pressure of 57 m.m. at 275°.
The liquid is remarkably sensitive to moisture, for water
instantly decomposes it into arsenious oxide and phenol.
Halogens do not form additive compounds with it, but chlorine
and bromine convert it into arsenic trichloride or tribromide
and trichlor- or tribromphenol. The second member, the para
cresyl ester, .\s(OC(H4CH3)3, is similarly obtained, and is like-
wise an oily liquid, boiling at 293° under 20 m.m. pressure,
and endowed with similar properties. The benzyl ester,
As(OCHXcH5)3, has also been isolated in an analogous
manner, but is not quite so stable as the two esters just de-
scribed, being more or less decomposed upon distillation in
vacuo ; it may be obtained practically pure, however, by heat-
ing the product of the reaction in an oil bath to 200° under low
pressure. It reacts with water simil.-.rly to the two other esters.
In addition to these liquid aromatic arsenious esters, the fi-
naphthyl ester, A':(OCj,,H-)j, ha; been prepared by the action
of arsenic trichloride upon the sodium derivative of 5-naphthol.
As the sodium compound is in this case completely soluble in
ether, the arsenic chloride reacts with great energy. The
arsenious naphthol ester crystallises from the ethereal solution
after decantation from the precipitate 1 common salt, in colour-
less aggregated crystals, which melt at 1 13°-! 14°, .and are
readily soluble in alcohol and benzene in addition to ether.
Water immediately decompose; them, and in boiling water the
products of the decomposition, arsenious oxide and ^n-iphthol,
dissolve completely.

The additions to the Zoological Society's Gardens during the
past week include a Green ^AonVey {Cercopithecus callitrielius, ? )
from West Africa, presented by Mis; Florence Grefiia ; a
Honnet Monkey (Afacacus sinicus, 9 ) from India, presented
by Mr. K. J. Davidson; two Polar Hires [Lepus glacialis)
from Norway, presented by Mr. O. Gude; a Commoi Bidger
{Meles taxus) from Berkshire, presented by The Dake
of Wellington ; an Irish Stoat (Putorius hiliernicus) from
Ireland, presented by Viscoant Powerscourt ; two Antipodes
Island Parrakerls {Ctanorhamphus unicotor) from .Antipodes
Island, New Zealand, presented respectively by Sir Walter
L. BuUer, K.C.M.G., and Mr. William E. Collins; two
Scarlet Tanagers (Raniphocatus brasilitis) from Brazil, pre-
sented by Mr. Robert E. Graves ; a Red and Blue Macow
{Ara maeao) from South America, deposited ; two Griffon
Vultures {Gj>ps fulvus) from Egypt, purchased ; an Egyptian
Gazelle (Gazella dorcas, i ) from Egypt, received in exchange ;
a Great Kangaroo (Macropus gigjnleus, i), a Rufous Rat
Kangaroj (Hypsiprymnus rufescens), born in the Gardens.

OUR ASTRONOMICAL COLUMN.

The Variable Spak Z Hkrcl' lis. —This recently dis-
covered variable star turns out to be one of exceptional interest.
It was first suspected of variability by the Potsdam observers,
and subseiiuent observations by Clianiller and Hartwig seemed
to show that it was a star of the Algol type. Early in the pre-
sent year Dr. Duncr announced that the new variable was pro-
bably of the V Cygni type with unequally bright components,
since he found unequal minima alternating in periods of forty-
seven and forty-nine hours. Returning to the subject
(Astrophysical fournil, \\n\\). Dr. Duner gives the data
on which his conclusion was b.ased, and derives s iinc in-
teresting results as to the probable conilitution of the system.
The normal magnitude of the star is 6 89 ; at principal minimum
it falls to S 05, aud at secondary miuLmum to 7'3S. Hence,

April 25, 1895J

NA rURE

617

A-

the relative degrees of brightness at these times are i, \, and \.
and assuming that the eclipses are central, it is easily shown
that the observed magnitudes may be explained by supposing
that the two components are of equal si/,e, while one is twice as
bright as the other. The unequal duration of the minima
further indicates that the orbit is an ellipse with an eccentricity
of o 2475, ^f"! '' ''* calculated that the semi-axis major of the
orbit IS six times the diameter of the stars. The plane of the
orbit passes through the sun, and the line of apsides is inclined
at an angle of 4° to the line of sight. The stars revolve in this
orbit in a period of 3 days 23 hours 48 minutes 30 seconds.

It seems probable that this variable may form a connecting
link between Algol, which consists of a bright and adaik body,
and Y Cygni, consisting of two stars of e^jual brightness.

The Diameter of Nrpiune. — With the Lick telescope
and an eyepiece magnifying 1000 diameters. Prof. Barnard finds
the mean angular diameter of Nepiune, when reduced to the
mean distance from sun 300551, to be 2"'433. This corre-
sponds to an actual diameter ol 32 900 miles, which is from two
to four thousand miles less than that stated in most of our text-
books.— Astronomical yournal^ No. 342.

INDUCED MAGNETISM IN VOLCANIC ROCKS.

N interesting note by G. Fulgheraiter, on the magnetism
induced in volcanic rocks by the earth's magnetic field,
appears in ihe A/li delta A'eale Accatiemia dei Lincei (vol. iv.
part 5, March 3, 1S95). The author has performed ? number of
experiments on volcanic rocks, in order to determine the amount
of induced magnetism left when, after heating to such a tem-
perature that they entirely lo-e their permanent magnetism,
they are either allowed to cool slowly or are suddenly cooled,
in each case under the influence of the earth's field. From such
observations he hopes to be able to deduce some conclusions as
to the conditions under which the rocks experimented on, which
were originally permanently magnetised, became magnetised.
The rocks are cut into small pirallclopepedons weighing about
50 grams, and such that the length is about two or three times
the depth or breadth, care being always taken to cut the
rock so that the axes of these pieces were vertical when
the rock was in its place in the earth. The intensity of magneti-
sation was in every case measured by the method of deflection ;
a freely suspended magnetic needle being deflected by the
sample, which was placed with its length east and west. After
measuring the intensity of magnetisation of the sample , they
were heated to redness, and then either allowed to cool slowly,
or are rapidly quenched with their axes veri ical. Their magnetic
moment was determined, first immediately they were cool, and
then after they had stood under the influence of the earth's field
for three months. The specimens of basalt examined may be
divided into two groups : in the first may be placed those
specimens which were originally only slightly magnetised, and
in this case, after heating to reiness, the magnetisation is always
increased, but to a very different degree in the different speci-
mens. The second group includes those basalts which were
originally strongly magnetised, and in this case after heating
the magnetisation was considerably reduced. In both groups
the magnetisation underwent no change duiing thtee months,
and sudden cooling gave the same results as slow cooling.
Experiments have also been made on tuff and peperino. The
results obtained with the first of these rocks are similar to those
obtained with the first group of basalts. Peperino, however,
differs in that, before being heated, lis coercive force seems
! Imost nil, the bar becoming only temporarily magnetised.
After healing, the character of the rock is altered, as
it can now become permanently magnetised and behaves just
like the tuff. From this the auihor concludes that peperino
has been formed at a low temperature, probably by the action
of water on cinders, Ac.

THE FREEZING-POINT OF DILUTE
SOLUTIONS.

(^ORRKCT determinations of the freezing-point of dilute
^^ solutions are of fundamental importance in connection
with the general theory of the subject, and it is therefore any-
thing but satisfactory to find that, in spite of the closeness with
whicn the individual results of the same observer agree amongst
thennelves, the results of different observers are in many cases

NO. 1330. VOL. 51]

widely separated. For example, the following values have
been given as the molecular depression of the Ireezing-point
in ihe case of a i per cent, aqueous solution of sugar: —
202, .\irhenius ; 207, Raoult ; 201, Pickering; 218, W. C.
Jones; i Si, Loomis. The results of Jones and Loomis, both
of whom claim increased accuracy for the methods they employ,
differ by some 18 per cent, fhe theoretical value of the
molecular depression, calculateil from the meliingpoint and
heat of fusion of ice, is I 86. The cause of these differences
has given rise to much discussion. Pickering has attempted to
show that Jones's results, wherein the temperature was read to
the ten-thousandth of a degree, were affecied tiy thermometer
errors. Jones has replied that his thermometer was tested.
Kohlrausch has drawn attention to probable sources of error in
Jones's method, but is compelled to admit that the differences
between the results of Jones and Loomis must, in ih; main, be
due to some unkrown source of error.

A definite step in the direction of clearing up this point is
made in a recent number of the Zeit chrift fur phyiikalisclie
Chemic. Here Nernst and .\begg emphasise the lact that the
observed freezing-point must in general be different from the
true freezing-point, or the temperature at which solid and liquid
are in equilibiium. They point out that a partly-frozen liquid,
uninfluenced by the temperature of its surroundings, will strive
to reach the true freezing-point at a rate which, at any instant,
may be taken as proportional to the difference between its actual
temperature and the true freezing-point. Again, in practice,
on account of the limited amount ot substance employed, and
the effect of the temperature of the surroundings, &c. , unfrozen
liquid strives to reach a definite tempfrature, which may be
termed the "convergence temperature." On these assumptions
it is easy to show that the observed freezing-point, or the tem-
perature at which the thermometer becomes steady, will only be
the true Ireezing-point if the "convergence temperature " is
equal to the true freezing-point, or if R, the rate at which the
temperature of the partly frozen liquid approaches the freezing-
point, is infinitely great as compared with r, the rate at which
the temperature of the unfrozen liquid approaches the " con-
vergence temperature.' If one ol these conditions is not ful-
filled, corrections delerinmed experimentally have to be applied.
For dilute solutions of alcohol and common salt the corrections
were found to be inappreciable under the experimental con-
ditions described in the paper. Here the value obtained for
R, although, as is always ihe case, it was largely diminished
by the lag of the thermometer, still was sufficiently large
as compared with the value of r. in the case of sugar,
however, R was so small that by varying the experimental
conditions, a i per cent, solution gave molecular depressions
varying between 16 and 21 — limits which are even further
apart than those given by the results of previous observers. On
correcting the observed depressions in the manner described,
they all gave practically the theoretical value.

X^ithout these corrections, observed freezing-points are thus
held to be functions of the size of the apparatus used, the
temperature of the cooling-bath, the rate of stirring which
largely affects the " temperature of convergence,'' &c.

Kvidence is also given of the futility of expressing freezing-
points to the ten-thuusandth of a degree. It may readily happen
that the above correction is as high as 001, and as the mode of
deducing it is but approximate, in such a case 0°00I or o°oo2
would be a favourable estimate of the error of the end result,
even if satisfactory corrections could be applied for the alteration
in the concentration of the solution produced by freezing, and
the ordinary sources of error incidental to the method of ex-
periment. J. W. Rodger.

THE EXAMINATION CURVE.

T F the resulisof the examination of a mixed body of candidates
be plotted out on the graphic method, ihey will be found,
in accordance with a well-known law of statistics, to approxi-
mate to a curve having a more or less rapid gradient at either
end, and a mid-region of gentler ascent. Fig. I, for example,
shows the results of an examination of 27 students in physical
geography, the scale of marks running vertically fiom 10 to 90,
the examinees being arranged horizontally at equal distances
apart from the lowest to the highest. The larger the number
of candidates the more flattened ilocs the mid-region of the
curve tend to become, .\gain, in any series of examinations,
the mean results of which are plotted out, the more uniform

6iS

NATURE

[April 25, 1895

ihe standard of difficulty of the papers set, the flatter is the mid
region of mediocrily. Fig. 2 shows the mean results of ten
separate examinations, of different students conducted by six
examiners, in history, English liteiature, geography, physical
geography, physics, botany, arithmetic, and Euclid. They are
taken without special selection from the returns of class
examinations in University College, Bristol. The standards
were somewhat markedly different ; in some the head, in others
ihe t.iil, being excessive ; hence the mid-region is not so
flattened as it probably would have been had a larger series
been taken. The results indicate, however, sufficiently well

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Examinees.

Fig. I.

the general nature of the examination curve. The total range
of marks being from 175 per cent, to S4 per cent., 15 out of
the 30 students fall within the mid-region of from 40 per cent,
to 60 per cent.

It is not my purpose to attempt to determine how far the
form of the lower end, or tail, of the curve is due to incapacity
on the one hand, or to sheer idleness on the other, and how far
that of ihe upper end, or head, of the curve is due lo exceptional
ability on the one hand, or to industry and hard work on the
other. Whichever cause preponderates, we may say that, at
any rale with pupils who have got beyond the school-boy stage.

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Fig. 3.

and very largely with them too, Ihe teacher's chief field of
influence is in the preponderant mid-region of mediocrily.
Those in the tail of the curve either cannot or will not profit by
hi« ministrations ; lho.se at Ihe head of the curve may be trusted
to do well without his aid, or even in spite of his interference.
It if on the body of the curve that he can do his best work.

It is, at first sight, somewhat remarkable that the general
form of the curve persists as we ascend throu|>h a series of
graded examinations. It might well be supposed that the tail
would be eliminated in the lower examinations ; and the results

NO. 1330 Vf L. 5ll

of my own observations show that the tail does tend to flatten
out and become raised as we ascend. But it is by no means
got rid of. It flattens because we have eliminated the hope-
lessly idle and those who have altogether mistaken their
vocation. It persists because at each stage there are those
whose limils of capacity have been reached. .\ student whose
capacity may bring him into upper mediocrity in matriculation,
may drop hopelessly into the tail when he proceeds to work for
the degree. I was informed, on good authority, at the Cape,
that whereas the Kaffir lads were often ahead of white boys in
the early siages of education, the limits of their capacity were
soon readied, and they were left behind by those whom they
had before easily beaten. .\\. each stage there .ire pupils for
whom the work isbe)ond their powers ; and they inevitably fall
into the tail.

In the traditional division of candidates into three classes,
the most rational method is to place in the first class those at
the head of the curve, the mediocrities in the second class, and
the tail in the Ihird class. For many years it has been my
custom as an examiner to plot out on the graphic method the
results of each examination. The advantage of doing so is
that one thus sees at a glance the distribution of the examinees.
One can also more leadily see where the divisions should run
between the several classes. It is irrational to fix beforehand
some arbitrary number i>f marks to form the limiting line above
which the candidates are to be called first class, those below
this and above another arbitrarily chosen number being ranked
in the second class. The limit must be de'ermined- -and even
then it is often only determined with difficulty — by an inspection
of the curve. The form of the curve, and the level of medio-
crity in ihe scale of marks, enable one to decide whether the
paper has been too hard or too easy. If too hard, the level of
mediocrily will be low, and the tail ir.ordinately large ; if too
easy, the level of mediocrily will be high, and the head not
well differentiated from the body.

The examination curve may be commended to the special con-
sideration of those who have to deal with large numbers of
candidates in connection with the Education Department and
that for Science and Art. .\nd I would recommend to the con-
sideralion of these who have the control of Civil .Service and
.•\rmy Examinations the excellent suggestion made by Dr. J.
Venn, in a paper on the " Correlation of Mental and Physical
Powers," contributed to Ihe J/.'h/j/ for October 1S93. In these
examinations large numbers of candidates compete for a limited
number of v.icancies. Let the results be expressed in an
examination curve. It will have a well-marked head, a longish
body of mediocrity, and a decided tail. We may cheerfully
eliminate the tail ; it consists of duffers intellectually. We
m.ay select the head for entrance ; it consists of men of marked
intellectual superiorily, so far as the examinations are an adequate
test thereof. If the he.id exhausts all the vacancies, well and
good. But if the number of vacancies involves an extensive
incursion into the body of mediocrity, then it will be found
that the lower selected candidates will be very little superior
intellectually to the higher rejected candidates. The last ten
selected, and the ten seniors among the rejected, will piobahly
be separated by a comparatively small number of marks.
Moreover, it is a well-known fact, cxferlo cr^tie, thai, if, after
an extensive set of papers has been looked over and carefully
marked, an interval of time be allowed to elapse, and then the
papers are gone over again, the result of this re-examination is
that the head and tail remain practically unchanged, but that
there is not a little redistiilmlion among the mediocrities.
Furthermore, if a different examiner look over the papers,
the head and tail of his curve will not difler nitirkedly in
arrangement orfoim from those of his predecessor ; but among
the mediocrities there will be not a litlle shifting of places.
While, therefore, such an examination as that for entrance to
Woolwich or Sandhurst serves to select the intellectual he.ad,and
lo reject the intellectual tail, it is by no means so elTectual in
classifying the candidates who fall within the body of medio-
crity.

Now if the same body of candidates be further examined by
some I hysical test (and Dr. Venn regards lung. capacity and
breathing power ihc best single physical test), it will be found
that in this resfcct theie will be a curve with well-inarkcd
hiad, a mediocre bcdy, and a lapidly descending tail. Hut the
inlcllcclual head and tail will not include the same candidates
as ihe physical head and tail. Let us therefore select from our
intellectual n.cdioctities those who fall within Ihe htad of the

April 25, 1895]

NATURE

bi9

physical examrnation curve. If we muit admit intellectual
mediocrity, let us, at any rate, secure that we have, in com -
peosation, physical excellence.

In practice this would necessitate the preliminary testing,
when they are undergoing their m;dical inspection, of all
candidates by means of the spirometer ; neither a difficult nor a
lengthy operation. No doubt, as Dr. Venn pDints out, breath-
ing power may to some extent be improved by practice, and
candidates would all (Ijck to a "spirometer-cramaiar." But
probably all of them would be the better for som; physical
cramming in this way. C. Lloyd Morgan.

UNIVERSITY AND EDUCATIONAL
INTELLIGENCE.

Cambridge. — Prof. W. Watson Chayne, F.R.S., has been
appointed an additional Examiner in Surgery for the present
term.

An intercollegiate Examination in Mechanical Science and
Engineering, for candidates for the Mechanical Sciences
Tripos, will be held, under the direction of Prof. Ewin^;, at the
end of this term, commencing on June 4.

The Somerset County Edaca'.ion Committee have adopted
a resolution in favour of establishing in the county a fixed
Dairy Farm School for aJults of both sexes. InUruction in
cheese and butter making, and in subjects allied there.o, woul J
be given. Provision is made for granting thirty sch ilar^hips,
giving free board an! tuition at the school for two months, to
formers' sons and daughters engaged in dairy w )rk. The
Committee have agreed that it 15 d;sirable to set up aa agri-
cultural side to one or more of the existing sacoadiry schools
in the county. It is hoped that in due course an agricaUural
college (or the West of England will ba provided by the com-
bined efforts of the local counties.

With the view of acquainting teachers with a course of ex -
periments in accoriance with the British Association Commi t-
tee's programme for the teaching of Chemistry in schools, the
Evening Schools Code, and the syllabus for Major Scholarship
examinations recently prepared by a committee of the Incor-
porated Association of Head Masters, Prof, .\rmitrong, F.K.S.,
will give a series of demonstrations at the City and Guilds
Central Technical College, on Saturday mornings, in May. The
special object of the course will be to explain the exact method
to be followed in carrying out a carefully arranged series of
very simple qualitative and quantitative experiments calculated
to impress the chief and most generally useful facts of chemistry
on children's minds whilst developing their powers of ob-
serving and reasoning.

It has often been urged against the educated natives of India,
that they are admirable at adaptation, but are altogether at a
discount where original research is concerned. The Hon. Mr.
A. Cadell commented upon this failing in a recent ad Ireis to
Convocation of .\llahabad University. His advice was that
debating societies, which are so common a feature of student-
life, should give place to natural history societies ; the object
would be to foster the true scientific spirit in the native mind.
In this connection, some remarks (which we quote from the
Allahabad Morning Post), made by Prof. Ingram, of the Madras 1
Educational Service, indicates that the complaint as to the want
of scientific research by natives of India is not without founda-
tion. In a recent contribution lie says:— "Now, if India is
not helping in this work, if she is supplying no additional infor-
mation, and is offering no aid towards the consummation of
this unity, her claim to be regarded as in any sense a scientific
country, is null and void. No matter how assiduously her
students may devote themselves to studying the science course
of their University curiiculum ; if it all end there, it is nothing.
But need it end there .' What country could offer greater
facilities for scientific research than India? Here is a country
teeming with animal and plant life ; but the systematic biology
of India is still in a nebulous condition. Why are no students
devoting themselves to collecting and collating, and studying
the plaints of their districts, or the insects that abound within
their walls? It would be hard, too, to find a country better
suited than India, with her clear atmosphere and cloudless skies,
for the study of the stars orof other atmospheric phenomena. In
these ways, and in a thousand other?, we might be advancing

the cause of knowledge. But we can scarcely be said to have
begun yet." By way of remedy. Prof. Ingram suggests the for-
mation of an Indian Royal Society, or sone such association as
would serve the same purposes here as the Riitish Association
does at home. It is possible, however, without going to that
length, to utilise the resources already at hand. India is not
without its scientific societies. There are the .\siatic Society of
Bengal, the Indian Science Association, and the Bombay
Natural History Society, all of which are amply sufficient for
the purposes of scientific research.

NO. 1330, VOL. 51]

SCIENTIFIC SERIALS.

American J otirnal of Science, April. — Niagara and the Great
Lakes, by F. B. Taylor. By a correlation of the abandoned
shore lines, moraines, and outlets, and the gorges, recently-
submerged shores, and rivers of this region, the author is led
to the view that the lakes were at firit glacial and ice-dammed,
falling by stages as the outlets changed on withdrawal of the
glacier-dams. By the withdrawal ol the glacier the Niagara
river was opened, and the upper lakes became united. The
land was gradually depressed at the north, and finally led to
the opening of Nipissing outlet, which was then brought down
to the sealevel, and marine waters filled the three upper lakes,
the Ontario, St. Lawrence, and Winnipeg basins. The sub-
sequent raising of the Nipissing outlet made the upper lakes
fresh again. Then followed the stage of the second Lake
Algonquin and that of the second (present) Niagara lakes.
Lake Superior became independent. The Great Champlain
uplift took place at the north-east, and the formation of the St.
Clair delta began, and continues to the present day. — Disturb-
ances in the direction of the plumb-line in the Hawaiian Islands,,
by E. D. Preston. There appears to be a disturbance of more
than a minute in the direction of gravity at the south point of
Hawaii. At Kohala the plumb-line is deflected half a minute
towards the south, and at Kilaieha nearly as much towards the
north, the disturb.'.nce being in both cases towards the moun-
tain. The deflection at the south point is also northward, and
is caused by the great masses of Mauna Loa and Mauna Kea. —
Structure and appendages of Trinuclctu, by Charles F. Beecher.
The three posterior thoracic endopodites are very similar, and
in a general way closely resemble those of Triarthrus from the
same region of the thorax. They are, however, comparatively
shorter and stouter, and could not be extended beyond the ends
of the pleura. The two distal joint; are cylindrical, with well-
marked articular surfaces and ridges. The joints preceding
these proximally become much wider, flattened, and produced
into transverse extensions which carr>' large tufts of set.^ at the
end. The exopodites seem to b; composed of slender joints,
the distal exites being long and slightly curved outwards. They
carry very long, close-set, overlapping lamellose fringes, which
evidently had a branchial function. The characters of the
appendages indicate an animal of burrowing habit, which
probably lived in the soft mud of the sea-bottom, much after the
fashion of the modern Limulus. In addition lo its limuloid form,
the absence of eyes seems to favour this assumption. So does
the fact that many specimens have been found preserving the
cast of the alimentary canol, showing that the animal gorged
itself with mud, like many othjr sea-bottom animals.

Wiedemann i Annaten der Pliysik iind Cliemie, No. 3. —
Electric conduction and convection in feebly conducting
dilute solutions, by E. Warburg. The alteration of conductivity
produced by a current in bodies like aniline, the phenomena of
convection exhibited by them, and their apparent deviations
from Ohm's law, can all be explained on the supposition that
their conductivity depends upon an electrolyte of which the body
is a very dilute solution. Bodies were investigated whose con-
ductivities went down to 5 x to"''. The similar behaviour of
still worse conductors, like xylol, benzol, oil of turpentine, is
probably due to the same cause. — Ratio of scctionri contraction
to longitudinal dilatation of iron rods during magnetisation, by
A. Bock. By magnetisation the constants of elasticity of soft
iron are altered to an extent not exceeding o"5 per cent. The ob-
servations indicate lh.at flexure diminishes, torsion also decreases,
and the ratio of sectional contraciion to longitudinal expansion
increases. Iron becomes more incompressible in the magnetic
field (see p. 614). — Freezing points of some binary mixtures of
heteromorphous substances, by Albert D.ihms. Euteclic mixtures

620

NA TURE

[April 25, 1895

give no aniform crystallisation product, but always a hetero-
geneous mechinical mixture, consisting of solid solutions of the
components in each other, and in the liiniiing cases oi ihe com-
ponents themselves. The composition of euteciic mixtures —
i'.^. those mixtures of two bodies which have the lowest fusioj;
points — does not correspond to simple molecular proportions of
the components. In euteciic mixtures the process of solidifica-
tion is in general more complicated than in chemically homo-
geneous bodies, owing to complex supercooling. Equimole-
cular solutions often show approximate correspondence of
fusing points, 'also for the higher concentrations. Menthol,
C,(,H,,OH, exists in two modifications, which explains the
diverjjences of the freezing points of even the most dilute solu-
tions in menthol. — On glow discharge in air, by C. A. Mebius.
Straight lines represen:ing the relation between strength of
current and difference of potential for different distances between
the electrodes, are not parallel, the divergence increasing with
Ihe extent to which the air has been modified by the current.
The fall of potential gradually decreases with a constant or an
increasing current. These changes are probably due to the
formation of nitric oxide, as was proved with the spectroscope.

Bulletin dt fAcadc'mu KoyaU de lielgiqui. No. 2.— On a
new class of ethers : methylene lactate, by Louis Henry.
Methylene monolactate, CH0.CH3 CjHOj, obtained by heating
lactic acid with polymerised metbanal, is a colourless mobile
liquid, with a stiong odour resembling metbanal, and an ex-
tremely pungent tasie. Its density is I 1974 at i'^" C.,and it
boils with remarkable regularity at 153 to 154°. — Comparison
of the astronomical coordinates referred to the instantaneous
(astronomical) pole and the (geographical) pole of inertia
respectively, by Ch. Lagrange. The discovery of the sensible
character of the variations of latitude and longitude is not of
such a nature as to render necessary the substitution of geo-
graphical axes to instantaneous ones in astronomy. The mean
values of the latitude and the longitude will be the geographical
characteristics of Ihe spot. But for the points of the heavens,
the result of the substitution of geographical for instantaneous
axes would have the eminent disadvantage of affecling all their
coordinates with diurnal variations 300 times greater. This is
a simple geometrical consequence of the fact that every day the
geographical and the instantaneous axes describe a cone about
the resultant, and that the geographical cone is 300 times more
open than the instantaneous cone.— Critical temperatures of
mixtures and of water, by F. V. Dwelshauvers-Uery. The
critical temperature of water was obtained by finding the critical
temperatures of aqueous mixtures of alcohol or acetone contain-
ing more and more water. The limiting value for water, as
derived from the acetone results, was 638' C, from the results
with alcohol, 641 C — Action of heat upon carbon bisulphide, by
Henryk Arctowsky. Carbon sesquisulphide, CS3, which is
obtained by exposing the bisulphide to the voltaic arc, may also
be obtained by keeping it at 250' C. for some time. It is this
l»ody whose presence in small quantities in commercial CSo
gives this product its pungent odour.

Thk number of the Journal oj lijtany for April is occupied
almost entirely by papers on descriptive botany, viz. on African
species of Eriosema, on South American species of I'oly^ala, on
British KuH, on hybrid Epihbta, and others on special species
or genera.

The liullelin of the Afinnesola Botanical Studies for March
contains a paper on a period ol growth in the fruit of Cucut-
tiita Pepo, by Mr. .\. P. Anderson, accompanied by an
elaborate series of tables and plates of curves. The other
articles in the same number refer exclusively to the Kiora of
Minnesota.

SOCIETIES AND ACADEMIES.
London.

Royal Society, Match 21. — "Experiments upon the In-
fluence of .Sensory Nerves upon Movement and Niiiriiion of the
Limbi.' (I'rclimii aty communication.) By Ur. V. W. Moll and
Dr. C. S. Sherrington, F. K.S.

Claude Bcrnaid first showed, by cxpctiincnls upon frogs, the
impairment of movement in a limb deprived of sensation by
cutting the |x»terir>r ipinal roots. The authois have, by an
cxteniive and varied scries, of experiments on the monkey,

NO. 1.^30, VOL. 51]

demonstrated the important tSle played by sensation in the
performance of voluntary movements.

The experiments deal separately with the upper limb .-ind the
lower limb. The phenomena do not essentially differ, but are
more striking in the former.

Summary of Experiments. — The limbs were deprived of all
sensation, superficial and deep, by cutting the "whole series"
of posterior spinil roots. For the upper limb, 4th cervical to 4th
thoracic inclusive. F"or the lower limb, 2ad to loih post-
thoracic inclusive.

Animals with a limb \\\\i% deprived of all forms 0/ sensation
from the time of operation onwards, even up to four months,
have never been observed to use it in any finer and delicately
adjusted movements. For example: the foot is not used in
climbing or grasping, nor is the hani. The animal does not
use the hand to defend itself, or even to satisfy hunger, when
prevented from picking up food by any other w.ay, than by
using the desensitised hand. It must be concluded, therefore,
that there is actual inabiliiy to perform the movements in ques-
tion. Occasionally in struggling, coarse movements of the
shoulder and elbow take place ; but, as a rule, the arm hangs
do*n helplessly. The movements abolished are those most
literally represented in the cortex cerebri. Damage to the
pyramidal tract is not the cause of the loss of movement,
because degeneration is not found in the spinal cords ; moreover,
stimulation of the cortex cerebri evokes movements in the
desensitised limb even more readily than the normal.

The effect of section of the " whole series, "except the one
root which supplies the apex of the limb, produces only a very
slight impairment of movement. Any trophic changes that
occur are due to pressure and microbic infection.

"Is Argon contained in Vcgeable or .\nimal .Sub-
stances?" By George W. MacDonald and Alex. M.
Ivellas.

.\t Prof. Ramsay's suggestion, experiments were undertaken
by the authors to see whether argon could be obtained from
nitrogenous vegetables or from animal tissues.

It is concluded that there is no appreciable quantity of argon
in peas (or at least that the aigon cannot be obtained with
the nitrogen by Dumas' method).

An experiment with regard to the presence of argon in
animal tissues was also negative in its results. Mice were
selected for the experiment, because the nitiogen from the
whole animal could b.: conveniently coUecied by Dumas'
method.

Chemical Society, March 21. — Dr. .\rmstrong, President,
in the chair. The following papers were read : — The volu-
metric determination of sugars by an ammoniacal cupric solu-
tion, by i,. I'eike. The author has deviled a modification ol
Pavy's method of estimating sugars, and gives tables showing
the reducing power of amm0niac.1l cupric solution for solutions
of various sugars. — The action of hydrogen sulphide on anti-
monic acid solutions, by O. lio.^.-k. The author demonstrates
the existence of compounds of the composition SbX^ ; he has
obtained the tetrasulphide Sb.jSj, and a double compound ol
the composition 3KCI, 2SbCl4. — Action of hydrogen sulphide
on antimonic, arsenic and telluric acids, by li. lirauner. — The
atomic weight of tellurium, by B. Brauner. From its position
in the periodic table, tellurium should have an atomic weight
between 123 and 125, whilst the number actually obtained is
12771 ; for this and other reasons the author concludes that
tellurium is not a simple substance, although attempts to elVect
a separation of its constituents have failed. The author sug-
gests that tellurium is a mixture or compound of two elcmeuts,
one of which occupies the position of tellurium in the periodic
table, and the other of which is the hypothetical "triargon." —
The hydrolysis of maltose by yeast, byG. 11. Morris. — -Studies
in isomeric change. Part iv. lithylben/enesulplionic acids, by
G. T. Moody. The sulphonation product of ethylbenzene
yields only one sulpbonic acid, and not two, as stated by
Chtuslschow. The para-acid is obtained thus : the ortho-acid
can be prepared by sulphonating and subsequently reducing
elhylbromobenzenc. — 18 lithoxyiiaphthalenesulphonic .acids.
The arrest of isomeric change at an intermediate stage, by A.
I.apworlh. 1 )aring the sulphonation of ethoxynapluhalene at a
low temperature the 2 : l-sulphonic acid is the first |>roduct.
fjn allowing the mixture to stand, however, this sjiontaneously
changes into the 2 : I'-aciJ. Some oxypyridine derivatives, by
Miss A. ]'. .Sedgwick and N. Collie. Starting from ^chloro-
aa'-dimethylpyridinc and 07 dichloro-a'-methylpyridine, tbe

April 25, 1895]

NA TURE

621

authors have succeeded in prepiririT; a number of new
oxypyridine derivatives. — Oi the colouring principle of
Toildalia acitleata and Evodia meticfolict, by A. G, Perkin
and J. J. Hummel. — Some ethereal derivatives of sircolactic
acid, by P. Frankland and J. Henderson. The molecular
rotations, molecular deviations an 1 asymmetry products of a
number of alkylic salts of sarcolactic acid and its acidic
derivatives have been investit^ated. — Electrolysis of potassium
alloethylic camphorate, by J. Walker and J. !Ienderson. The
chief products of the electrolysis of p-jtassium allo-ethylic
camphorate are salts of allo-campholyiic acid, CHuO^, and
allo-campholhetic acid, C,.,H;„,04. — Trimethylsuccmic acid, by
W. A. Bone and \V. \\. Perkm, jun. — New isomeric sulphonic
chlorides derived from camphor, by F. S. Kipping and W. J.
Pope. The authors describe two isomeric chlorocamphene-
sulphonic chlorides and their derivatives.

Royal Meteorological Society, April 17. — Messrs. F. C.
Bayard and W. Marriott communicated a paper on the frost of
January and February 1895 over the Rritish Isles. The cold
period which commenced on Pecember 30 and terminated on
March 5 was broken by a week's mild weather from January
14 to 21, otherwise there would have been continuous frost
for sixty-six days. Temperatures below to' F., and in some
cases below zero, were recorded in parts of England and Scot-
land between January 8 and 13, while from the 26th to the
31st and from February 5 to 20, temperatures below 10'
occurred on every day in some part of the British Isles. The
coldest days were February 8 to 10. The lowest tempera-
tures recorded were: -17° at Braemar and -11 at Buxton
and Drumlanrig. The mean tempera'ure of the British Isles
for January was about 7°, and for February from 11° to 14°
below the average, while the mean temperature for the period
from January 26 to February 19 was from 14' to 20' below the
average. The distribution of atmospheric pressure was almost
entirely the reverse of the normal, the barometer being highest
in the north and lowest in the south, the result being a con-
tinuance of strong northerly and easterly winds. The effect
of the cold on the public health was very great, especially on
young children and o'd people. The number of deaths in
London due to diseases of the respiratory organs rapidly
increased from February 2 to March 2, when the weekly
number was 1448. or 945 above the aver.age. Rivers and lakes
were frozen, the ice tieing more than 10 inches thick. The
frost will long be remembered for its effect on the water. pipes
all over the country, in many cases householders being without
water for more than nine weeks. .\s the result of inquiries
the authors find that mains have frozen which have been laid
as low as 3 ft. 6 in. from the surface of the ground to the top of
the pipe. It appears, however, that the nature of the soil
had far more to do with the depth to which the frost penetrated
than the intensity of the frost itself From a comparison of
previous records, the authors are of opinion that the recent frost
was more severe than any since 1814. — Mr. Birt Acres read
a paper on some hints on photographing clouds.

Mineralogical Society, April 2. — .\ paper was read by
Mr. Spencer upon enargite. Several new forms were discovered
upon the specimens of this mineral examined. The parameters
calculated from the measurements were

a:li:c— 0'8694 : I :-O'8308,
numbers which differ somewhat from those previously given by
Dauber. The habits of the crystals and their mode of twm-
ning were fully discussed, ami the fact pointed out, bearing
upon the possibility of the identity of clarile with enargite, that
measurement of cleavage fragments of clarite gave angles
identical with those existing lietween the prism cleavages of
enargite when three crystals are twinned together. — Mr. A. E.
Tutton exhibited his new instrument for culling, grinding, and
polishing accurately orientated section-plates and prisms of min-
eral or other crystals, and demonstrated the readiness with whirS
the cutting disc or grinding or polishing lap may be driven by
a small electric motor. Mr. II. A. Miers suggested the possi-
bility of simplifying the instrument somewhat for the commoner
purposes of the mineralogist, by employing only one driving gear
and making the cutting disc and laps interchangeable ; he also
suggested the experiment of using carborundum for the cutting
edge instead of diamond dust. — .Mr. Miers exhibited a crystal
o( hrandi/e, the new arseno-sulphide of thallium discovered by
Kreuner ; also a fine crystal of dhicile, the mineral which had,
at his suggestion, been examined for argon by Prof. Kamsay.

NO. 1330, VOL. 51]

The specimen exhibited was from the neighbourhood of Mns»,
and this variety, as well as (hat from .\ren lal, had been foun I
to yield the spectrum of helium.

Edinburgh.

Royal Society, January 21.— Prof. Sir \V. Turner, Vice-
President, in the chair. — Drs. Gulland and Noel Paton
communicated a paper on the absorption of carbotiydrates from
ihe inte.'.tine. — Prof. Ewart read a paper, by Dr. [. D. F.
(iilchrist, on the torsion of the molluscan body. — Prof. Tait
communicated a note on a curious property of determinants.

February 4. — Prof. J. G. M'Kendrick, Vice-President, in the
chair. — Prof. Crum Brown communicated a note on normal
nystagmus. — Sir W. Turner read a note on M. Dubois' account
of I ithecanlhropoid remains recently found in Java. The
remains are a skull, a thir<l molar tooth, and a left femur.
They were found in a bank of a river in Java, at some distance
from each other, and at different times. M. Dubois supposed
that he had established the exis'ence of a connecting link
bptween the ape and man, and he named it the "erect ape
man," in recognition of the differences from man and the ape.
.Sir W. Turner remarked that it was not at all certain that the
three bones belonged to the same creature. A comparison of
the skull wiih several specimens of the skulls of aboriginals,
left him unconvinced that it might not have belonged to a
human neing. The features of the femur could all be made out
in a large collection of human thigh bones, and the tooth had
quite as much resemblance to the tooth of a human being as to
the tooth of an ape. He considered that the remains were of
a low human type.

February iS.~The Hon. Lord M'Laren, Vice-President, in
the chair. — Prof. Chrystal discussed a theorem regarding the
equivalence of systems of ordinary linear differencial equations
with constant coefficients, and its application to the theory of
such systems. — Dr. C. G. Knott communicated a note on
volume-changes in iron and nickel tubes when magnetised.
He dealt specially with the effects which are caused when the
lubes are closed by a non-magnetic cap instead of a cap of the
same metal as the tubes themselves. — Dr. W. Peddie compared
the case of yellow-hlue blindness, described by him some
weeks ago, with the case recently described by v. Vintscbgan
and Hering. In the present case, unlike the latter, the whole
range of the .spectrum is visible. So far as the tests have yet
been carried out, the presence of red seems to be very easily
recognised, but all other colours seem to be nearly, or entirely,
grey. Only one neutral point (near D, in tho yellow part of
the spectrum) seems to exist.

March 4.— Sir Douglas .Maclagan, President, in the chair. —
At the request of the Council of the Society, Dr. Munro gave
an address on lake dwelling research. Whatever was the object
of these dwelling=, or the causes of their development, it is
certain that they were for centuries the characteristic dwellings
of the early tribes of Central Europe. Research on the subject
began with the discovery of remains in a bog in Ireland, more
than half a century .ago. Another discovery was afterwards
made in Switzerland, and gave new significance to the Irish
discovery. Dr. Munro sketched the results of the investigations
made in Switzerland and in other parts of Europe, especially
Italy. Perhaps no part of Europe is more prolific in remains
than the valley of the Po. The first great discovery made in
Scotland was in a loch in Wigiownshire. When the Inch was
drained, several aitificial islands were found, and evidences of
early .Scottish civilisation, previously unknown, were discovered.
.\mong the articles found were canoes and Roman broijze
dishes. Subsequent Scottish discoveries were descrilicd, and
then the recent discoveries in Bosnia were dealt with. The
coincidence of the style of art in the ornaments recently found
at Glastonbury with that of the North German articles is
peculiarly significant.

Scottish Meteorological Society, March 27. — Prof.
Copeland, Astronomer Royal for Scotland, in the chair. — Mr.
R. C. Mossman gave a paper on "The Frost of 1895," in
which he pointed out that Ihe severe frost began on December
28, and ended about February 20, covering a period of fifty-four
days. During this lime the average temperature of the British
Isles as a whole was 8° below normal, the greatest deficiency
being in the central highlands of Scotland and the midland
districts of England. .Vt the same time barometric pressure
was highest in Scandanavia, Lapland, and West of Russia, and
lowest about Spain ; an almost exact reversal of the normal

622

NA TURE

[April 25, 1895

winter distribution. Thus cold, dry, and therefore heavy, air
was drawn from the northeast over the British Isles, not only
lowering the air temperature directly, but clearing the sky of
the usual winter cloud layer, and thus allowing free radiation
at night, with consequent low night temperatures in valleys
where the chilled air can accumulate and lie stagnant. Places
thus situated recorded temperatures below zeio Fahrenheit, the
lowest being — 17° at Braeraar, and - 11° at Drumlanrig. At
western sea-coast places the frost seldom lasted for more than
twenty-four hours without a break ; while at inland stations,
such as Kingussie and Braemar, the temperature never rose to
the freezing point for fifteen consecutive days in February. No
very low temperatures were recorded on Ben Nevis, the lowest
being 2° above zero. On February 18, 19, and 20 the tem-
perature on Ben Nevis averaged 18° higher than that at Fort
William, 44CO feet below it, showing that the summit was in
the down draught of the anticyclone then lying over Scotland ;
while at sea level the warmth and dryness of this upper current
was not felt. The cold extended all over Europe, including
the South of Spain and the Riviera, but scarcely touched North
Africa. Though snow fell in Tunis, Algeria was beyond the
cold area, the winds there being mostly westerly. To the north
Iceland was the only part of Europe outside the influence of
the north-east winds, and the winter there has been mild and
open. — Mr. A. G. Herberlson presented an interim report on
hygrometric work at Ben Nevis. He also gave an account of
the Meteorological Observatory at Montpellier, France,
describing many of the instiumcnts employed there, and also
pointing out ihe excellent results got from regular phenological
observations. — Mr. Mossraan gave some notes on " Auroras in
the Norih-east of Scotland 1773 to 1S94," mainly taken from
data at Gordon Castle (Banffshire) and Inverness. The average
number of auroras in this district for the 122 years is seven per
annum, bit the numbers vaiy from fifty ca.'^es in 1870 to none
at all in jixleen yeais of the lecoid. An intimate connection
was shown between sun-spots and auroras ; maximum sun-spot
periods being the time whtn auroras were frer|uent and
brilliant, » bile with the absence of sun-spots there were few or
Done. No aurota was observed in any year between May 23
and July 22, that is, wilhin four or five weeks of the summer
solstice; and ihe rest of the year shows two maxima, a primary
in October and a secondary in February.

DuntiN.

Royal Dublin Society, January 23.— Prof. J. Mallet Purser
in the chair. — Mr. G. H. Carpenter read a paper on a collection
of Lepidoptera from Lokoja, West Africa.— Prof. A. C.
Haddon and Mr. J. E. Duerden ilescribtd some species of
Actiniaria from Australia and other countries. Ten species,
most of them new to science, were described anatomically, and
their relationship to other members of the group discussed. —
Prof. Iladdon then gave a paper on a branched worm-tube. —
Mr. Duerden followed with some notes on Ihe Hydroida
and Polyzoa collected during the Royal Dublin Society's
Fishery Survey on the West Coast of Ireland. In this paper
the author describes two new species of Pcri^onimus, and
records the occurrence of Cainpanulitui paiticula, G. O. Sats,
for the first time for the British seas. — A voluminous mono-
graph of the marine and freshwater Oslracoda of Ihe North
Atlantic and of North-Western Europe (Sections ii.-iv. : Myo-
docopa, Cladocopa, and Platycopa) was presented (through
Prof. A. C. Haddonj by Dr. G. S. Brady and the Rev. A. M.
Norman. — At the meeting held February 20, Prof. Grenville
A. J. Cole in the chair, Ihe following papers were read : —
Dr. V. Ball, C.B., F. R.S., made a communication in which
he gave an historical account of the gold nuggtts found in the
county Wicklow.— Prof. W. J. Sollas, I-.R.S., read a paper
descriptive of the systems of Eskers in Ireland. Some beau
tiful photographs of nebula; and clusters of stars, taken at
Daramona, co. Westmealh, were afterwards exhibited by Mr.
^V. E. Wilson.— At Ihe meeting of March 20, Prof. G. F.
Fitzgerald, F. R.S., in Ihe chair. Prof. Sollas read a paper
upon Ihe age of the earth. — Prof. James Lyon demons'rated
lome of Ihe errors that arise from Ihe imperfect alignment of
the slide lathe. If the lino joining the centres of a slide la he
ii not laiallel to the line of motion of Ihe saddle, Ihe paih of a
cutter fixed in a bar which is rotated between the centres is a
plane which is not perpendicular to the direction of motion.
Any piece of material being bolted lo saddle, and having a
hole bored in it by the cutter, would be traversed by a hole the

NO. 1330, VOL. 51]

shape of which would be the projection of the cutting circle
on a plane perpendicular to the line of motion of saddle — i.e.
an elliptic cylinder would be the result. In the second case, if
the poppet-head centre be higher than the fixed centre, and a
bar of material be turned between Ihe centres by means of a
tool placed in the saddle at a heit,ht above the bed about equal
to Ihe height of the ctntre point of the axis of bar above the
bed, the result will be a hyperboloid of revolution, since this
surface is generated by a straight line (the palh of the tool),
which is always at a fixed distance from a given axis, is not
parallel to it, and does not intersect it.

Paris.

Academy of Sciences, April 16. — M. Marey in the chair.
— Observations on argon, ils fluorescence spectrum, by M.
Berthelot. The fluorescence of argon, when charged with
benzene vapour and submitted to the action of the silent dis-
charge, is described at length. It is noted that, with the second
sample of gas supplied by Prof. Ramsay, and under the con-
ditions'of the experiment, the condensation lakingplace amounted
to only 6 to 10 per cent. The author cannot yet explain the
dift'erent behaviour of Ihe first sample as regards condensation.
The following approximate measurements have been made in
Ihe spectrum of the fluorescent light : A yellow line at A 579
corresponding lo Ihe 575 argon line and 578 of the .aurora
borealis ; a green line at X 547 corresponding wilh Crookes'
group 549 to 555, and perhaps with 557 of Ihe aurora;
violet lines 43S and 436 corresponding with Crookes' 433
and 430, and with an important aurora line. — A con-
tribution to Ihe study of variability and capacity of trans-
formation in microbiology, as illustrated by a new variety of
anthrax bacillus (Bacillus anthracis clai-iformis), by M. A.
Chauveau and M. C. Phisalix. The cultivation obtained from
the lymphatic ganglion of a guinea-pig inoculated with at-
tenuated anthrax bacilli consisted of a new type which retained
only in a very slight degree the immunising power of the
attenuated culture, and no longer had any toxic action beyond
that evidenced by a certain rise in temperature of Ihe inoculated
subject. The authors believe the Bacillus anthracis clavi-
forittis to have been certainly derived from virulent Bacillus
anthracis, but they have not as yet succeeded in bringing back
the new variety to the original virulent form. — On the minimum
temperatures observed this winter at the summit of Mont Blanc,
by M. J. Janssen. A description is given of the mounting of
the minimum thermometers. The following minima have been
recorded: Mont Brivent -26''C. ; Mont Buet -33''C. ; Mont
Blanc -43"C. — Secular variation and ephemerides of terrestrial
magnetism, by General Alexis de Tillo. — Researches on
assimilable nitrogen and ils transformations in arable Land, by
M. Pagnoul. The conclusions are drawn that : (l) Abundant
rains may carry off from rich soils considerable amounts of
nitric nitrogen. (2) Plants growing on the soil are able to
prevent this loss. (3) Carbon disulphide arrests the action of
the nitric fetinent temporarily without killing it. (4) The
ammoniacal form is a transition state for organic nitrogen pass-
ing into the nitric form ; carbon disulphide causes Ihe temporary
suspension of Ihe .action at this stage. (5) The nitrous form is
also an unstable transition slate. — On the products of combustion
in the electric arc, by M. N. Grchanl. Carbon monoxide is
produced and, in confined spaces, has produced illness among
the workmen employed in electric light stations. — On a question
concerning the singular points of algebraical left-handed curves,
by M. G. B. Guccia. — Summation of series by means of
definite integrals, by M. Petrovitch. On types of groups of
subslitutions of which the order equals the degree, by
M. R. Levavasseur. — On the theory of the system of
differential equations, by M. A. J. Slodolkievitz. —
On Rondelei's rule for woods, and beams loaded
on end, by M. C. Mallczos. Rondelei's rule is reduced for
wood lo a parabolic formula. The curve of limit loads for
wood, lion, and brass, between wide limits for Ihe ratio of
length of beam to smallest side of transverse section, may be
replaced by an arc of a single parabola. — Electric discharge by
illumination of substances which are mediocre conductors, by
M. Edouard Braiily.— On a new method for Ihe measurement
of Itmperalutes, by M. Daniel Beilliclot. The author pro-
p OSes the ddeimination of density of gases, by means of their
rcfraclive indices as investigated by interference fringes, as a
basis for measurement of temperature by a property of gases
independent of Ihe envelope. — On the presence of helium in

April 25, 1895

NA TURE

62-

cli veite, by M. P. F. Cleve. A letter in which the author gives
the wave-lengths of linei observed in the spectrum of gas
obtained from cleveite by heating with potassium bisulphite.

The argon lines were not observed. — On the definite combin-
ations of metallic alloys, by M. II. Le Chalelier. — On the
.iliphalic aldehydes C; H„,..0, by M. Louis Ilenry.^.Vclion of
hilogens on pyrocatechol, by M. H Cousin. — Oi the drying

roperty of fatty matters in general and their transformation into
clastic products analogous to linoxine, by M. Ach. Liviche. — O.i
the composition of so ne French and foreign o its of the 189^
crop, by M. Bolland. — On the existence of abnormil v.inatijns
of pressure with the height, a vertical gradient, by M. L-
Teisserenc de Bort.

Berlin.

Physiological Society, March r.— Prof, du Bois
Raymond, President, in the chair. — Dr. Weintraud spoke on
the formation of uric acid in nun. After the view ihit the
e<cretion of uric acid is in direct relationship to the proteids
of the food had found no support from th; experimental siile,
the theory hid been propounded thit it is relate I to the
breakiug-d own of leucocytes. This view was supported by
experiments in which the administration of nuclein and
xanthin to man had increased the output, of uric acid ; but, on
the other hand, similar experiments on dogs had always yielded
negative results. The speaker had experimented on several
individuals by substituting thymus gland, rich in nuclein, for
the ordinary flesh of the food. The increase! excretion of
phosphoric acid in the urine showed that the nuclein was
largely resorbed, and a constantly large increase in the execre-
tion of uric acid was at the same tine observed; the latter
disappeared again at once when ordinary flesh was substituted
for the thymus gland. Apart from theoretical considerations,
it appears that foods rich in nuclein or xanthin should be
avoided by patients suffering from excessive formation of uric
acid. — The President and Dr. Sklarek made some communica-
tions as to argon, recently discovered by Lord Rayleigh and
Prof. Ramsay.

March i5.^Prof. H. Munk, President, in the chair. — Prof.
Liebreich stated that he had found in propyl alcohol a means of
separating the cholesterin fats of the skin into those with a high
and those with a low melting point. The former exhibit all the
characteristics of a wax, and are distinguished by their fixed
melting point and by their containing cerotic acid. By extracting
human nails and vernix caseosa he had obtained a quantity nf
cholesterin fats which resembled in all points the cholesteri.i
ethers of the skin. He further demonstrated a new chemical
reaction which shows the existence of the inert region on the
surface of fluids and in capillary tubes in which chemical
changes are taking place. It consists in the interaction of
chloral hydrate with sodium carbonate and gold chloride; and
since all these reagents are solid it is evident that evaporation
h.as no effect on the production of ths inert space. ^Dr. E.
Flatau exhibited two series of nerve preparations, the first
consisting of isolated ganglion cells and neurons prepared, by
a modification of Golgi's method, partly from the cerebrum
and partly from the cerebellum and medulla. The second
series, prepared by Marchi's method, was intended to show
that in the VVallerian experiment on degeneration, not only
does the peripheral stump degenerate after the section, but
that the central end also undergoes a secondary degeneration
after the break-up of the now inactive ganglion.

Meteorological Society, March 5. — Prof. Hellmann,
Presidenr, in the chair. — After the Piesident had presented the
fourth number of the Reprints containing the oldest charts of
terrestrial magnetism, Dr. Siiring gave an account of his ob-
servations on the temperature and humidity near a surface of
snow. They were made last winter on the Bfocken, and this
winter in Potsdam, and in the following manner. One ther-
mometer was placed on the snow, and another at the usual
height above the surface, either exposed or ]>rotected, while at
the same time an aspiration-thermometer placed I cm. aljove the
snow recorded the temperature of the air. It was found that
the size, shape and position of the thermometer lying on the
snow, as well as the condition of the sno*-surface, &c., had a
considerable influence on the temperature recorded by this
instrument; the observations had therefore boon restricted 10 a
deteimination of the dilTerence between the temperature of th:
snow and that of the air above it, in its relations to clouds and
to the motion and temperature of the atmosphere. It was found

NO. 1330, VOL. 51]

that the diflFerence \ra> lessened as the sky became more clouded,
and when the sky was completely clouded during a fall of snow
the temperature of the snow's surface was higher than that of
the air. As the temperature of the atmosphere fell, the dif-
ference became greater, but was lessened as the motion of the
air increased in rapidity. On the whole, the dilTerence was much
less on the Brocken than in Potsdam. As to the influence of
the snow-surface on the humidity of the air, the speaker had
arrived at the result that evaporation from the snow is much
more frequent than condensation from the air, but that they are
about equal in amount. Prof. Hellmann spoke on the, as yet,
uninvestigated velocity of the windin Berlin, basing his remarks
on the indications during ten years of a self-registering ane-
mometer placed at a height of 33 '5 metres above the ground in
the tower of a house which was originally quite isolated. In
later years this house was surrounded by others, but this fact
did not in any way affect the working of the anemometer, whose
constants were determined at the marine observatory at Ham-
burg and the central observatory at St. Petersburg. Taking a
year as a whole, the maximum rate was observed in March, the
minimum in September, and during these months the variations
were least. The average for the year is 5'i metres per second.
The above-named periods of maximum and minimum have also
been observed at a number of other stations, viz. Paris, Munich,
Prague, Vienna, and Cracow. Winds with a velocity less than
the average are more frequent than those with one above the
average. The frequency of storms, as measured in hours, is
greatest in January and March ; it increases in October, and
sinks rapidly in April. The daily period of greatest velocity
lies between one and two o'clock p.m.

Physical Society, March 8. — Prof, du Bois Reymond,

President, in the chair. — -.\ftcr Prof Lampe had referred to the
deaih of their late member. Prof. Wjrpitiky, Dr. VV. Wien
spoke on the testing of pyrometers made, according to Le
Chatelier, of platinum and platino-rhoiium, and connected with
an appafa'us constructeci by Reiser and Schmidt for measuring
not only the voltage of the thermo-electric currents, but also the
corresponding temiieratures. The testing was carried oat by
determining the melting-points ofcoppcr, silver, platinum, palla-
dium, and nickel, whicti, as fine wires, formed thesolJer-joints
of the platinum and platino-rhodium ihermo-elements. These
were heated in porcelain tubes, and the current was broken when
the respective wires melted. In these experiments platinum
must be protected from carbon, copper from oxygen, and palla-
dium from hydrogen. It is imposdble here to enter into all the
details referred to by the speaker. — Dr. \V. von Uljanin gave
an account of his experiments on polarisation by oblique radia-
tion from silver, platinum, and black glass. Assuming that the
radiation from the heated pLates is determined by the refraction
of their substance, it was lound that the curves thus arrived at
corresponded in the case of silver very closely with those
obtained experimentally. In the case of pUtinum, whose
surface is very easily altered by heating, the experimental values
were always less than those required by theory ; in the case of
black glass the correspondence of the values was greater, but
not so complete as in the case of silver. — Dr. Raps introduced
an improvement in his automatic air-pump, designed to facilitate
the filling and emptying of the mercury, and at the same time
to protect the pump from the consequent risk of breakage. The
result was arrived at by means of a chamber for the expmsionof
air. — Prof. Vogel demonstrated the experiment, already de-
scribed in Nature, whereby a half black and half white disc
with black patches on it produces different colours, when rotated
at a moderate speed, according to the direction of the rotation.

March 22. — Prof Planck, President, in the chair. — Dr. Rubens
exhibited several galvanometers, and explained in detail the
arrangement and advantages of one he had constructed for the
measurement of reversing currents, but which can also be
readily adapted for currents in one direction. — Dr. Rapsspoke
on a new regulator for synchronous motion, especially as re-
quired in telegraphy, explaining Us principle and constractioa
on a model.

Amsterdam.

Royal Academy of Sciences, December 29, 1S94. — Prof,
van de Sande Hakhuy/cn in the chair. — Mr. MacGillivray com-
municated the results of an invcuigation m.ade iiy .\Ir. D. Mac-
Gillivray in the Boeihaave Laboratory at Leyden, aud wh'.ch
proved that the germs of tuoerculosis are nut destitute of the
power of locomotion, but possess this power, if the conditions
of life are favourable.

624

NA TUKE

[April 25, 1895

February 23, 1895. — Prof. Hubrecht brought forwarj a new
hypothesis to explain the origin of the amnion. Birds and
reptiles have been looked upon as possessing the normal type
of amniogenesis from which that of the Mammalia had to
be further derived. The primitive Insectivores offer far better
s'.ariing points. In the development of the heigeh^g's amnion,
another path is found along which it is easy to connect both
the higher Mammalia and the Sauropiid.T. The hedge-
hog allows a comparison to be made between the tro-
phoblast with the outer layer of the amphibian ecto-
derm. Thus it would be possible to trace the first origin
of the amnion in the Anamnia. — A paper containing full
particulars, and accompanied by several plates, was presented
for publication in the Academy's I'erhandelitigen, under the
title: "Ueberdie Phylogencsedej Amnions und die Bedeutung
des Trophoblastes." — Mr. Suringar read a paper on "family
relations in the vegetable kingdom," as set forth in a sketch in
the form of a genealogical tree, designed by the author to
illustrate his University lectures. — Mr. Franchimont pre-
sent^J, on behalf of Dr. P. van Roniburgh, two papers.
(a) On some nitro derivatives of dimethylaniline. By nitration
of dimelhylanilioe in a great quantity of sulphuric acid, as well
as by treating meianitrodimethylaniline with diluted nitric acid,
'.wo diniiro derivatives were obtained ; a yellow one fusing at
176°, and a red one fusing at 1 12 . In the yellow one there is
a nitro group that may easily be substituted. By further nitration
it yields two triniiro derivatives : a yellow one melting at 154°
and an orange-coloured one melting at 196. The red diniiro
derivative yields onlv the orange-coloured trinitro derivative.
All of them are finally converted into the same tetranilrophenyl-
moDomethylnitramioe, viz. :

C.H.(NO-), (2, 3, 4, 6) (N.CH,.NOo) (i).

From their relations or properties the following structure is
deduced :

Trinitro Dimethylatxilint.

IS4' = C6H,N(CH3U (I), (NOo), (2, 3, 4).
I96°=C«H,N(CHA. (I). (NO.,)3 (3, 4, 6).

Diiiilio Dimethylaniline.

176°-C«H,N(CH:,1.. (I). (N0.,)..(3, 4)-
ii2*=C,H,N(Ciy,(i), (NO..). (3, 6).

{b) On addition products of symmetrical trinitrobenzol. Hepp
has found that with aromatic amines S. Irinitro-benzol yielded
coloured addition products. With brucine. Dr. van Romburgh
arrived at the same result : it formed brownish red needles
fusing at 15S' ; strychnine did not do so under the same cir-
cumstances. With trinitro-benzjl, indol yielded gold-coloured
needles melting at 187 , .skatol, orange-coloured ones melting
at 183°, and pyrrol, gold-coloured ones melting at 95° ; ihe
last-mentioned gave off the pyrrol to the air in a few hours (at
25°). All these compounds consisted of one molecule to one
molecule of trinitrobenzol. Pyridine and quinoline did not
form such compounds ; the former caused trinitrobenzol to
crystallise in large crystals. Piperidine, nicotine and phenyl-
hydrazine gave rise 10 red tints, but crystallised compounds
could not be obtained. With other nitro compounds, too, as :
C,Hj NMe, NH,NO, (1 ; 3 : 4), and C„H,N.Mej.NUMe.NO..,
(I : 3 : 4), trinitrobenzol yielded crim-on products, melting
reipectively at 130 and 144', ani being composed of a mole-
cule of each of the constituents.

March 30. — Prof. Van de Sande Bakhuyzen in the chair. —
Mr. Bakhuis Roozeboom has, in conjunction with Dr.
Hoilscnia, investigated the behaviour of hydrogen to palla-
dium, from o' to 190 , and from o to 6 aim. pressure. It
results (torn Ihe observations that, contrary to the opinion
of Troost and Ilautefeuillc, there exists no such compound
a< I'd, II, neither can the phenomena observed be explained
by admitting the existence of two solid solutions. The
absorption proceeds gradually, as if there exists but one solid
kolution. There is, however, at low temperatures a period in
which the concontralion rises much more rapidly with the
prcmure of hydr Jgcn than before or afterwards. This behaviour
pre-ent> an analogy to the conduct of gases near their critical
temperature.

GoTTINGEN.

Royal Society of Sciences. — In the Nachrichlett, part
I, lor 1S95. appear the following contributions in the depart-
ment of mathematics and physics : —

December 1S04 — I. R. Schutz : i Complete and general

solution of a fundamental problem in the theory of the potential.

-Robert Fricke : On the theory of ternarv quadratic forms with

integral complex coefiicienls. — J. Orth : On bacterial disorders

ol excretion in the renal medulla.

januar)' 1S95. — !• J*- Schu;z : Extension of Maxwell's law
of the distribution of velocities, deduced from the principle of
the minimum path. — E. Ehlers : On the viscera of ZiTtii/oiiV^n.
— I.udwig Rhumbler : Sketch of a natural system of classifica-
tion for the Tlialamoplioia. — Hermann \Vagner : The areaofthe
land surfaces of the earth according to zones. — R. Dedekind :
On the basis of the theory of ideals. — Ileinrich Burkhardt : Con-
tributions to researches on the foundations of geometry. — Franz
Meyer : On the structure of the discriminants and resultants of
binary forms. — Wilhelm Ilallwachs : On an aperiodic
amagoetic quadrant-electrometer, free from residual action.

BOOKS, PAMPHLETS, and SERIALS RECEIVED.

Books.— Royal linivcr.«iity of Ireland, Cal>;nd.-ir 18^5 (Dublin, Thoni) —
Soci^t^ d' Encouragement pour I'lndusirie Nalionale, .Annunire iSgs
(Paris).— Land. Bird^ and Gamc-Birds of New Knjland ; H. D. Minor
(Boston, Houghion).—Ttie Moon: T. G. Eljer (Philip) —R. Bradsha»\
Bathing Places and Climatic Health Resorts (K. Paul).— Soiialc Evolu-
tion : B. Kidd, aus dem Englischen Ubersekt von E. Pfleidcrer (Jeii.i,
Fischer). — Motive Powers and their Practical Selection : R. Bolton (Long-
mans).

Pamthlets. — Indexes to the Literatures of Cerium and Lanthanum :
Dr. W. H. Magcc (Washington). — Reports of Observations and Experi-
ments in the Practical Work of the Division of Entomology, U.S. Depart-
ment of Agricultnre(Washington).

.Skijials. — Journal of Anatomy and Physiology. April (Griffin) — Roy.il
Natural History, P.art 18 (Warnc) — American Naturalist. April (Pliil.i-
delphia). — Insect Life, Vol vi. No. 5: Vol. vii Nos. 1-4 (Washington) —
Ergebnisse der Meieorologischen Beobachtungen, Jahrg. xvi. (Hamburg)

CONTENTS p.\GE

Controversial Geology. By Prof John W. Judd,

F.R.S 601

Popular Weather Forecasts 602

The Mycetozoa 603

A New Work on Dyeing. By Walter M. Gardner. 604
Our Book Shelf:—

"The Fauna of British India, including Ceylon and

Hurnia."— W. F. Kirby 605

Letters to the Editor: —

The Oricin of the Cultivated Cineraria. —W. Bate-
son. F.R.S. . 605

The Age of the Earth.— Dr. Alfred R. Wallace,

F.R.S. ; C. Davison 607

Thf Burmese Chinped Flints. Pliocene not Miocene.

Dr. W. T. Blanford, F.R.S . 60S

The Mandrake. — Kumagusu Minakata 608

A Claim for Priority. —Alex. E. Outerbridge . . 60S
An Improved Method for the Microscopic Investi-
gation of Crystals. By A. E. Tutton ... 608
Microbes and Metals. By Mrs. Percy Frankland . 611

Professor James Dwight Dana 611

Notes 612

Our Astronomical Column : —

Tli'j Variable Star Z I lerculis 616

The Diameter of Neptune 617

Induced Magnetism in Volcanic Rocks 617

The Freezing-Point of Dilute Solutions. By J. W.

Rodger 617

The Examination Curve. ( ll'tlh Diagrams.) By

Prof. C. Lloyd Morgan 617

University and Educational Intelligence 6iii

Scientific Serials 619

Societiefi and Academies 620

Books, Pamphlets, and Serials Received 624

NO.

1330, VOL. 51]

Q Nature

1
N2

V.51
cop. 2

Physical &
Apnii-d Sci.
Serials

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